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Volume 98-B, Issue SUPP_21 December 2016 Canadian Orthopaedic Association (COA) and Canadian Orthopaedic Research Society (CORS) Annual Meeting, June 2016; PART 2.

B. Zomar S. Muir D. Bryant E. Vasarhelyi J. Howard B. Lanting

The purpose of our study was to prospectively examine early functional differences in gait between the direct anterior and direct lateral surgical approaches for total hip arthroplasty over the first three months postoperatively.

Forty participants were prospectively enrolled to either the direct anterior (20 patients) or direct lateral group (20 patients) based on their surgeon's expertise. Outcome measures were collected preoperatively at their preadmission appointment and postoperatively at discharge from the hospital, two weeks, six weeks and three months. We used the GAITRite® system to measure gait velocity, stride length, single-limb support and single-limb support symmetry. We also had participants complete the Timed Up and Go test and a series of questionnaires at each visit: WOMAC, SF-12, Harris Hip Score, and pain VAS.

Our primary outcome, gait velocity, was significantly greater in the direct anterior group at discharge and six weeks postoperatively with adjusted mean differences of 0.12m/s and 0.17m/s respectively. Single-limb support symmetry was also significantly better in the direct anterior group at two weeks, six weeks and three months with adjusted mean differences of 0.10, 0.09 and 0.04 respectively. The direct anterior group also had significantly shorter times to complete the Timed Up and Go test at two and six weeks with adjusted mean differences of −9.02s and −2.64s. There were no differences between the groups at any time point for the WOMAC, SF-12, Harris Hip Score, or pain VAS.

Preliminary results of our expertise-based study have found the direct anterior approach to total hip arthroplasty offers better early functional outcomes than the direct lateral approach.


P.R. Kim L. Gala P.E. Beaulé

The incidence of lateral femoral cutaneous nerve (LFCN) neuropraxia after anterior approach total hip arthroplasty has been reported to occur in up to 50% of patients. In the vast majority of cases there has been no functional impact it is unknown if symptoms persist or diminish over time. The aim of this study was to examine the natural history LFCN neuropraxia in a previously reported cohort of individuals after anterior approach total hip arthroplasty.

One hundred and forty three consecutive patients underwent direct anterior hip approach (DAA) between September 2006 and February 2009 of which 107 had been identified with LCFN neuropraxia. These 107 patients (39 THA; 68 HR; 44 Female & 63 male; mean age 55.4 (38.4–88.8)), were provided a self-reported questionnaire for sensory deficits associated with LFCN as well as severity of symptoms on a 10 point visual analogue scale (VAS). These were done at initial assessment and latest follow-up.

Sixty of the 107 patients (56%) completed their questionnaires at a mean follow-up of 5.4 years (24 THA; 36 HR). Twenty-two percent (13 of 60: 8 men & 5 women) had complete resolution of their symptoms (9 HR and 4 THR). Of the 47 patients (78%) still reporting symptoms of LFCN neuropraxia, the mean score on VAS decreased from a mean of 2.32 (SD:2.11) to 1.74 (SD:1.99). No limitation in activities was reported for 90% of patients (54 out of the 60). Of the 6 patients (10%) with limited activity they reported a mean VAS score of 4.4 (SD: 3.6 range of 0–8.4). The LFCN symptoms did not appear to be directly related to their activity limitation.

While LFCN neuropraxia can be a common complication following direct anterior approach hip replacement, almost a quarter of patients will have complete resolution of symptoms and the majority will have a decrease in their symptomatology. LFCN neuropraxia following DAA hip arthroplasty does not appear to lead to any functional limitations and is associated with a low score on VAS.


D.W.C Johnston L. Beaupre A. Alhoukail

Bearing surfaces in Total Hip Arthroplasty (THA) may affect implant longevity and hence patient outcomes. This randomised clinical trial (RCT) determined how ceramic-on-ceramic bearing (CERAMIC) THA affected joint-specific pain, function and stiffness, and prosthesis fixation/longevity over 10 postoperative years compared with ceramic-on-highly-crosslinked-polyethylene bearing (POLYETHYLENE) THA. This is a follow-up to previously reported five year outcomes.

Subjects aged less than 61 years were randomised to CERAMIC [n=48] or POLYETHYLENE [n=44] THA. Subjects were assessed using the Western Ontario McMaster Osteoarthritis Index (WOMAC) and the RAND 12-Item Health Survey (RAND-12) preoperatively, and at one, five and 10 years postoperatively. Plain radiographs were evaluated at 10 years for fixation and medical records were reviewed for revisions.

Of 92 subjects, six (7%) died within 10 years; 68 (79%) survivors provided radiographic and/or clinical follow-up at 10 years postoperatively. Improvements seen at five years in both the WOMAC and RAND-12 were retained at 10 years with no group differences (p>0.48). There were no failures/loss of fixation related to bearing surfaces/wear in either group. Over 10 years, three subjects in the POLYETHYLENE group had revisions that were related to recurrent dislocation; two revisions were performed within two years of surgery and one further subject underwent revision at 7 years postoperatively.

This is one of the first RCTs to examine 10 year outcomes between ceramic-on-ceramic and ceramic-on-highly-crosslinked-polyethylene bearing THA. Both bearing surfaces performed well out to 10 years in subjects who were less than 61 years at time of surgery.


D. Cinats A. Bois K. Hildebrand

Total Elbow Arthroplasty (TEA) is a procedure to treat a number of conditions including rheumatoid arthritis (RA), post-traumatic arthritis, and osteoarthritis. To date, there has been minimal literature published on the Latitude since its release in 2001. There is one study reporting outcomes from the Latitude, a German study published in 2010. The purpose of this study was to analyse outcomes from primary Latitude TEAs.

We performed a retrospective case series of 23 TEAs performed on 20 patients. 6 patients required revision surgery and were not included in the analysis. One patient was lost to follow up, resulting in 17 patients included for ROM analysis. All patients received Latitude TEA through a posterior approach and underwent a standard rehab protocol. 11 Patients were recalled at least two years post-op and were administered DASH and MAYO questionnaires. Complications such as triceps insufficiency, ulnar nerve dysfunction, infection, and aseptic loosening were recorded. Outcomes were compared using the Wilcoxon Signed-Rank test in STATA. Immediate post-op radiographs and patients most recent radiographs were analysed by a blinded upper-extremity surgeon not involved in the initial operation and analysed for loosening and implant malpostioning.

Mean follow up was 4.8 years (range 2.6–7.5 years). Analysis of 17 TEAs in 16 patients revealed no difference in pre-operative ROM and post-operative ROM for flexion (121°±20 vs 129°±16, p=0.13) extension (40°±27 vs 27°±15, p=0.19), pronation (73°±13 vs 75°±24, p=0.55) or supination (64°±22 vs 68°±14, p=0.52). Patients who underwent TEA for RA had a significant improvement in flexion (121°±15 vs 135°±10, p<0.02). There was a statistically significant improvement in flexion-extension arc post-operatively (101°±28) compared to pre-operative scores (83±23 degrees, p<0.02). DASH and MAYO scores were calculated from 11elbows in 11 non-revision patients able to return for examination. The average MAYO score was 87.9 with nine patients in the “excellent” category, two patients in the “good” category, one patient in the “fair” category, and one in the “poor” category. The average DASH score was 32.9. Two patients underwent revision for periprosthetic fractures, two patients underwent revision for infection, one underwent revision for aseptic loosening and two for radial head dissociation (rate of 30%).

This is one of the first studies examining the outcomes of the Latitude TEA. This retrospective case series demonstrates that the Latitude TEA has promising outcomes with respect to improving patient pain and functioning as assessed by the MAYO. Treatment using the Latitude TEA results in favorable functional outcomes for a majority of patients and offers an improvement in flexion-extension arc. Furthermore, our results are comparable to the MAYO scores reported by other studies analysing different prosthesis designs. The complication rate in our series was comparable to published rates of 20–40%.


S. Holmes A.P. Diaz G.S. Athwal K.J. Faber D.B. O'Gorman

Propionibacterium acnes infection of the shoulder after arthroplasty is a common complication. Current detection methodologies for P. acnes involve prolonged anaerobic cultures that can take up to three weeks before findings can be reported. Our aim was to develop a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) approach that is both sensitive and specific to P. acnes that would enable a 24-hour turnaround between biopsy and results.

Comparisons between the 16S ribosomal sequences of P. acnes and closely related bacteria identified two unique regions in P.acnes to which PCR primers were designed. Additionally, two unique restriction enzyme cut sites for HaeIII were identified within this amplicon. To test the PCR method, arthroscopic surgical biopsies were mechanically homogenised and boiled for 20 minutes to lyse the cellular membranes. PCR was performed using standard conditions followed by a one hour HaeIII enzymatic digest of the PCR product. Resultant fragments were visualised on polyacrylamide gels stained with ethidium bromide. All experiments included no-template controls to rule out reagent contamination and independently confirmed P. acnes DNA as a positive control. Serial dilutions of P. acnes cultures in Robertson's cooked-meat broth and spectrophotometric analysis of cellular concentration were used to assess the sensitivity of the PCR reaction.

A unique 564 base-pair PCR amplicon was derived from different strains of P. acnes. This amplicon was confirmed as P. acnes DNA by gel excision and DNA sequencing. HaeIII digests of the amplicon yielded 3 restriction fragments at the sizes predicted by in silico analyses. Sensitivity testing confirmed that as few as 10 P. acnes cells in a 50µl reaction volume could be detected using this assay. P. acnes was also detected in surgical biopsy samples.

P. acnes infections following shoulder arthroplasty are a serious complication placing a burden on the healthcare system and the patient due to the lengthy surgical revision process that follows. The infections are also difficult to diagnose. This unique assay combines the sensitivity of PCR with the specificity of RFLP mapping to specifically identify P. acnes in surgical isolates. We anticipate that this assay will allow us to determine if a biopsy is P. acnes positive within 24-hours of sampling, allowing for more aggressive antibiotic therapy and monitoring to avoid implant failure and revision surgery. Additionally, this PCR-RFLP method may decrease the false positive rate of extended length cultures due to P. acnes contamination.


G.D.G Langohr J.W. Giles J.A. Johnson G.S. Athwal

Despite reverse total shoulder arthroplasty (RTSA) being primarily indicated for massive rotator cuff tears, it is often possible to repair portions of the infraspinatus and subscapularis of patients undergoing this procedure. However, there is disagreement regarding whether these tissues should be repaired, as their effects remain unclear. Therefore, we investigated the effects of rotator cuff repair and changes in humeral and glenosphere lateralisation (HLat & GLat) on deltoid and joint loading.

Six shoulders were tested on an in-vitro muscle driven active motion simulator. Cuff tear arthropathy was simulated in each specimen, which was then implanted with a custom adjustable RTSA fitted with a six axis load sensor. We assessed the effects of 4 RTSA configurations (i.e. all combinations of 0&10mm of HLat & GLat) on deltoid force, joint load, and joint load angle during abduction with/out rotator cuff repair. Deltoid and joint loads recorded by the load cell are reported as a % of Body Weight (%BW). Repeated measures ANOVAs and pairwise comparisons were performed with p<0.05 indicating significance.

Cuff repair interacted with HLat & GLat (p=0.005, Fig. 1) such that with no HLat, GLat increased deltoid force without cuff repair (8.1±2.1%BW, p=0.012) and this effect was significantly increased with cuff repair (12.8±3.2%BW, p=0.010). However, adding HLat mitigated this such that differences were not significant. HLat and GLat affected deltoid force regardless of cuff status (−2.5±0.7%BW, p=0.016 & +7.7±2.3%BW, p=0.016, respectively). Rotator cuff repair did significantly increase joint load (+11.9±2.1%BW, p=0.002), as did GLat (+13.3±1.5%BW, p<0.001).

The increases in deltoid and joint load caused by rotator cuff repair confirm that it acts as an adductor following RTSA and increases deltoid work. Additionally, cuff repair's negative effects are exacerbated by GLat, which strengthens its adduction affect, while Hlat increases the deltoid's abduction effect thus mitigating the cuff's antagonistic effects. Cuff repair increases concavity compression within the joint; however, Hlat produces a similar effect by wrapping the deltoid around the greater tuberosity – which redirects its force – and does so without increasing the magnitude of muscle and joint loading. The long-term effects of increased joint loading due to rotator cuff repair are unknown, however, it can be postulated that it may increase implant wear, and the risk of deltoid fatigue. Therefore, RTSA implant designs which improve joint compression without increasing muscle and joint loading may be preferable to rotator cuff repair.


L.L. Nowak M. Vicente M. Bonyun A. Nauth M.D. McKee E.H. Schemitsch

Proximal humerus fractures are a common fragility fracture in older adults. A variety of treatment options exist, yet longer term outcomes of newer surgical treatments have not been extensively researched. Additionally, intermediate term outcomes following both surgical and non-surgical initial treatment of these injuries have not been evaluated at a population level. The purpose of this study was to utilise administrative data from Ontario, Canada to evaluate intermediate term outcomes following initial treatment of proximal humerus fractures.

We used data from the Canadian Institute for Health Information to identify all patients aged 50 and older who presented to an ambulatory care facility with a “main diagnosis” of proximal humerus fracture from April 1, 2004 to March 31, 2013. Intervention codes from the Discharge Abstract Database were used to categorise patients into fixation, replacement, reduction or non-surgically treated groups. We used intervention codes to identify instances of complication-related operations following initial treatment (including fixation, replacement, hardware removal, rotator cuff repair and irrigation and debridement [I&D]) at one year post initial treatment.

The majority of patients (28,369, 86.6%, 95% confidence interval [95% CI] 86.2–87.0%) were initially treated non-surgically, while 2835 (8.7%, 95% CI 8.4–9.0%) underwent initial fixation, 1280 (3.9%, 95% CI 3.7–4.1%) received primary joint replacement, and 276 (0.8%, 95% CI 0.8–1.0%) were initially treated with a reduction procedure. In the year following the initial treatment period, 127 (0.4%, 95%CI 0.4–0.5%) non-surgically treated patients underwent a replacement surgery, 292 (1.0%, 95%CI 0.9–1.2%) underwent fixation, and 12 (0.04%, 95% CI 0.02–0.07%) underwent a reduction procedure. Of the 2835 patients who received initial fixation, 57 (2.0%, 95% CI 1.6–2.6%) returned for a shoulder replacement, 80 received secondary fixation (2.8%, 95% CI 2.3–3.5%), 57 (2.0%, 95%CI 1.6–2.6%) underwent rotator cuff repair, 300 (10.6%, 95% CI 9.5–11.8%) had their implants removed, and 16 (0.6%, 95% CI 0.4–0.9%) returned for I&D. Of the 1280 patients who underwent initial replacement surgeries, 30 (2.3%, 95% CI 1.7–3.3%) returned for a secondary replacement, nine (0.7%, 95% CI 0.4–1.3%) underwent rotator cuff repair, and seven (0.6%, 95% CI 0.3–1.1%) had their implant removed. In the group who received initial reduction, eight (2.9%, 95% CI 1.5–5.6%) underwent a fixation procedure, six (2.2%, 95% CI 1.0–4.7%) received replacement surgeries, and five (1.8%, 95% CI 0.8–4.2%) each received rotator cuff repair and I&D in the year following initial treatment.

The majority of proximal humerus fractures in patients 50 and older in Ontario, Canada are treated non-surgically. Complication-related operations in the year following initial non-operative treatment are relatively low. The most commonly observed procedure following initial fixation surgery is hardware removal.


G.P. Slobogean G. Osterhoff N. O'Hara J. D'Cruz S. Sprague N. Bansback N. Evaniew

There is ongoing debate regarding the optimal surgical treatment of complex proximal humeral fractures in elderly patients. The aim of this study was to evaluate the cost-effectiveness of reverse total shoulder arthroplasty (RTSA) compared to hemiarthroplasty (HA) in the management of these fractures.

A cost–utility analysis using decision tree and Markov modelling based on data from the published literature was conducted. A single-payer perspective with a lifetime time horizon was adopted. A willingness to pay threshold of CAD $50,000 was used. The incremental cost-effectiveness ratio (ICER) was used as the study's primary outcome measure.

In comparison to HA, the incremental cost per QALY gained for RTSA was $13,679. One-way sensitivity analysis revealed the model to be sensitive to the RTSA implant cost and the RTSA procedural costs. Two-way sensitivity analysis suggested RTSA could also be cost-effective within the first two years of surgery with an early complication rate as high as 25% (if RTSA implant cost was approximately $3,000); or conversely, RTSA implant cost could be as high as $8,500 if its early complication rates were 5%. The ICER of $13,679 is well below the WTP threshold of $50,000 and probabilistic sensitivity analysis demonstrated that 92.6% of model simulations favoured RTSA.

Our economic analysis found that RTSA for the treatment of complex proximal humeral fractures in the elderly is the preferred economic strategy when compared to HA. The ICER of RTSA is well-below standard willingness to pay thresholds, and its estimate of cost-effectiveness is similar to other highly successful orthopaedic strategies such as total hip arthroplasty for the treatment of hip arthritis.


C.R. Mellano P.N. Chalmers R. Mascarenhas N. Kupfer B. Forsythe A.A. Romeo G.P. Nicholson

Patients over 70 years old have subclinical or impending rotator cuff dysfunction, raising concern about TSA in this population. The purpose of this study is to examine whether reverse total shoulder arthroplasty (RTSA) should be considered for the treatment of glenohumeral osteoarthritis in the presence of an intact rotator cuff (GHOA+IRC in patients older than 70 years of age.

Twenty-five elderly (>70 years) patients at least one year status-post RTSA for GHOA+IRC were matched via age, sex, body mass index, smoking status, and whether the procedure involved the dominant extremity with 25 GHOA+IRC patients who received anatomic total shoulder arthroplasty (TSA). Standardised outcome measures, range of motion, and treatment costs were compared between the two groups. Treatment cost was assessed using implant and physical therapy costs as well as reimbursement.

Patients who received RTSA for GHO+IRC had significantly lower pre-operative active forward elevation (AFE, 69° vs. 98°, p <0.001) and experienced a greater change in AFE (p=0.01), but had equivalent AFE at final follow-up (140° vs. 142°, p=0.71). Outcomes were otherwise equivalent between groups with no differences. In both those patients who underwent TSA and those that underwent RTSA, significant improvements between pre-operative and final follow-up were seen in all standardised outcome measures and in AFE (p<0.001 in all cases). RTSA provided these outcomes at a cost savings of $2,025 in Medicare reimbursement due to decreased physical therapy costs.

In patients over the age of 70 with GHOA+IRC, RTSA provides similar improvement in clinical outcomes to TSA at a reduced cost while avoiding issues related to the potential for subclinical or impending rotator cuff dysfunction.


E.A. West N. Knowles L. Ferreira G. Athwal

Shoulder arthroplasty is used to treat osteoarthritis, post-traumatic arthritis, and avascular necrosis. Modular components allow for natural variability in shoulder anatomy, including retroversion and head-neck angles. Surgical options include anatomic or guide-assisted cut at a fixed retroversion and head-neck angle. The purpose of this study was to determine the variability between head height (HH) and anteroposterior (AP) and superoinferior (SI) diameters using anatomic and guide-assisted humeral head cuts.

Computed tomography scans of 10 cadaveric shoulder specimens (5 male, 5 female) were converted to 3D models. An anatomic humeral head cut plane was placed at the anatomic head–neck junction maintaining the posterior cuff insertion for all shoulders by a fellowship trained shoulder surgeon. Cut planes were generated for standard implant head neck angles (125°,130°,135°, and 140°) and retroversion angles (20°,30°, and 40°) in commercial cutting guides, for a combination of 12 repeated cut conditions per specimen. The humeral HH and the head diameter were measured in the AP and the SI planes for anatomic and guide-assisted osteotomy planes. Differences were compared using a separate two-way repeated measures ANOVA for each dependent variable.

Guide-assisted cuts showed no significant effect on HH due to head-neck (p=0.205) or retroversion angles (p=0.190). These results persisted by gender (male: head-neck p=0.659 and retroversion p=0.386; female: head-neck p=0.204 and retroversion p=0.190). SI diameter increased by 1.3 mm with increasing head-neck angle (p<0.001), but there was no effect due to retroversion (p=0.148). A head-neck angle of 125° caused the greatest decrease in SI diameter of −2.8 mm compared to the anatomic cut, averaged over the retroversion range. The greatest reduction of SI diameter, −3.4 mm compared to anatomic, occurred with 125° head-neck angle and 20° retroversion. By gender, males showed a significant effect from head-neck angle (p=0.008), but females did not (p=0.077). There was no significant difference from retroversion in either gender group (male p=0.792; female p=0.057). There was no significant difference in AP diameter by head-neck (p=0.192) or retroversion angles (p=0.168). These results persisted in the males (head-neck p=0.420 and retroversion p=0.780). In females, there was no effect from head-neck angle (p=0.232); however, retroversion angle trended toward significance (p=0.050).

For patients whose natural anatomy falls outside the range of the commercial cut guides, templated resection may result in deviation from natural humeral head dimensions. Due to the large variability in anatomic retroversion and head-neck angles in the subjects of this study, further study with a larger sample size is needed to investigate observed trends. These preliminary results have implications for manufacturers to create guides to represent a larger segment of the population, and surgeons' intra-operative choice.


M. Daalder G. Venne M. Rainbow T. Bryant R.T. Bicknell

While reverse shoulder arthroplasty (RSA) is a reliable treatment option for patients with rotator cuff deficiency, loss of glenoid baseplate fixation often occurs due to screw loosening. We questioned whether an analysis of the trabecular bone density distribution in the scapula would indicate more optimal sites for screw placement. As such, the purpose of this study was to determine the anatomic distribution of trabecular bone density in regions of the scapula available for screw placement in RSA.

Seven cadaveric shoulders were computed tomography (CT) scanned, and then voxels of the scapulae were isolated from the CT volume (Mimics 15.0 Materialise, Leuven, Belgium). Analyses were conducted in a common, 3D coordinate system. Volumetric regions of interest (ROI) within the scapula were identified based on potential baseplate screw sites. ROIs included areas at the base of the coracoid process lateral and inferior to the suprascapular notch, in the posterior and anterior lateral spine and in the anterosuperior and posteroinferior lateral border. Hounsfield Units (HU) were extracted from voxels corresponding to trabecular bone within each ROI. Overall bone density was summarised as the frequency of HU values above 80% of the ROI's maximum density value. Paired, two-tailed t-tests assuming unequal variance were used for pairwise comparisons (P≤0.05). Intra-region analyses compared two ROIs within the same broad anatomical structure; inter-region analyses compared ROIs between anatomical structures.

Areas of the spine and lateral border of the scapula appeared to be denser than the coracoid process. Intra-region comparisons indicated no significant differences within ROI: coracoid P=0.43, spine P=0.95, lateral border P=0.41. ROI inferior to the suprascapular notch were on average 3.78% (P=0.08) and 6% (P=0.04) less dense than the anterosuperior and posteroinferior lateral border and 7.59% (P=0.006) and 7.72% (P=0.01) less dense than the anterior and posterior lateral spine. ROI lateral to the suprascapular notch were 6% (P=0.05) and 8.21% (P=0.02) less dense than the anterosuperior and posteroinferior lateral border and 9.8% (P=0.006) and 9.94% (P=0.008) less dense than the anterior and posterior lateral spine. There was no significant difference between the anterior spine and anterosuperior and posteroinferior lateral border (P=0.12, P=0.58), nor between the posterior spine and anterosuperior and posteroinferior lateral border (P=0.14, P=0.57).

Results from this study indicate that the spine and lateral border of the scapula contain denser trabecular bone relative to regions in the coracoid. The higher quality bone of the spine and lateral border should be favoured over the coracoid process when fixing the glenoid baseplate in RSA. Further research may support the redesign of the glenoid baseplate geometry to better integrate the anatomy of the scapula and improve implant survival.


D. Stachiw A. Malone A. Strang A. Matthews

We present 2 year results of a prospective natural history study of Type III Acromioclaviclular joint dislocation (ACJD) treated non-operatively. Previous natural history studies are compromised by inconsistent definitions of the grade of injury and non-validated scoring tools; they do not identify which patients will have ongoing symptoms. This trial documents the strength and subjective recovery over time, and identifies risk factors for poor outcome and need for surgery.

Patients with Rockwood Type III ACJD received a standardised rehabilitation protocol (6 sessions of physiotherapy). Clinical assessment was performed at presentation, 3, 6, 12 and 24 months after injury, including isometric strength testing, pain (VAS/10) and subjective scores – Subjective percentage of normal (SPON), American Shoulder and Elbow (ASES), Oxford Shoulder Score (OSS) and Quick Disabilities of Arm Shoulder and Hand (qDASH).

28 male patients were recruited, 26 reached 12, and 9 to 24 months follow up. Two required surgery and one emigrated. The mean age was 39 (15 to 67). Initial mean pain was 3/10, SPON 51% (6–95) and strength was 76% of the other side. By 3 months mean subjective recovery was 70% and strength 90%. Strength recovered to 99% of normal by 12 months but subjective scores remained at mean 90%; by 24 months subjective scores were mean 94%. 2 patients had subjective scores <80%.

There was a wide range of initial subjective scores and weakness after Type III ACJD. 95% of strength had recovered by 6 months and subjective scores recovered to 94% of normal by 24 months. 4 patients (14%) did poorly with 2 requiring surgery. Low initial subjective score and inability to abduct the arm at presentation were risk factors for a poor outcome.


L. Naggar

Massive irreparable rotator cuff tears (MIRCTs) represent a difficult situation especially in painful and pseudoparalytic patients. A new technique, consisting of an arthroscopic implantation of an inflatable biodegradable “balloon”, serving as a temporary subacromial spacer, has been introduced recently for MIRCTs. The purpose of this paper is: 1) to present the efficacy and safety results of patients treated with the balloon; 2) to show that these results are maintained over time, after balloon degradation; 3) to compare these results to published results of other procedures available for MIRCTs.

This paper presents the first group of 22 patients (females/males 13/8, one bilateral), treated in a single-surgeon, prospective and on-going series of 97 shoulders operated with the balloon, since September 2010. The mean age is 69.3 (52–86) and the average follow-up 52.5 months. The balloon is inserted arthroscopically and inflated with saline. The procedure is simple with a short operative time (10–20 min). It can also supplement partial repairs, especially of the subscapularis, as well as repairable massive tears with bad tissue quality. The balloon is not used in severe cuff tear arthropathy or complete insufficiency of the external rotators. Final outcome scores, Constant (CS) and UCLA scores are obtained at least three years after complete balloon degradation (which occurs within 12 months), and are also compared to those of other treatments available for MIRCTs.

No device related safety issues were observed in this group. Good results, including rapid pain relief and restoration of active motion, which maintained over time, are obtained in 85% of the patients. The CS has improved significantly (average preop/postop: pain 2.9/12.7; ADL 6.8/17.4; ROM 22.8/36.6; strength 3.1/5.6; TOTAL 35.8/72.3; NORMATIVE 42.7/86.4). The UCLA score has also improved significantly (preop/postop: pain 1.9/8.6; function 3.9/8.6; active flexion 3.5/4.5; strength in flexion 2.4/3.4; satisfaction 0/4.5; TOTAL 11.2/29.8). Pseudoparalysis is reversed (average preop/postop flexion 86°/156.8°). The CS and UCLA score for the balloon are superior compared to published results of debridement, biceps tenotomy/tenodesis, partial repair, tuberoplasty and latissimus dorsi transfer. CS (86.4/63.8), CS pain (12.7/11.9) and flexion (156.8/128.0) are also better for the balloon compared to the reverse prosthesis.

The balloon is indicated for MIRCTs, as well as reparable massive tears with a high risk of retear. The implantation is a straightforward and short procedure, which has excellent safety profile and positive effect on painful MIRCTs including pseudoparalysis. The balloon provides significant improvement in the CS and UCLA score that persists way beyond its degradation. The balloon patients' shoulder function is superior to the other available treatment options. Additional studies are needed to further confirm the effectiveness of the balloon as a first line treatment for MIRCTs.


D.M. Sheps J. Chepeha D. Magee L. Beaupre

Athletes involved in repetitive overhead shoulder rotation demonstrate increased external rotation and decreased internal rotation range of motion. Deficits in internal rotation have been linked to the development of shoulder pathology. The purpose of this study is to determine if a posterior shoulder stretch program is effective in increasing dominant arm internal rotation and horizontal adduction range of motion in overhead athletes identified as having reduced mobility and posterior shoulder tightness.

Thirty-seven overhead athletes in volleyball, swimming and tennis, with internal rotation range of motion deficits greater than or equal to 15°, were randomised into intervention or control groups. The intervention group performed the “sleeper stretch” daily for eight weeks while the control group performed usual activities. Independent t-tests determined whether internal rotation and horizontal adduction range of motion differences between groups were significant and two-way repeated measures analysis of variance tests measured the rate of shoulder range of motion change. Reported shoulder pain and function were also obtained at each evaluation.

Significant differences were found between the intervention and control groups' internal rotation and horizontal adduction range of motion at eight weeks (p<0.001 and p=0.003 respectively) compared to baseline (zero weeks) (p=0.19 and p=0.82 respectively). Significant changes in internal rotation were detected in the intervention group at four weeks (p<0.001) with further adaptations noted at eight weeks. Horizontal adduction improved at a slower rate demonstrating significant changes at eight weeks (p=0.003). Reported shoulder pain and functional ability (p=0.002) were different between the study groups at eight weeks.

Overhead, collegiate-level athletes with an internal rotation deficit greater than or equal to 15° are able to significantly increase internal rotation and horizontal adduction range of motion by performing a posterior shoulder stretch exercise for eight weeks.


D. Burns J. Chahal S. Shahrokhi P. Henry D. Wasserstein C. Whyne J. Theodoropoulos D. Ogilvie-Harris T. Dwyer

Anatomic studies have demonstrated that bipolar glenoid and humeral bone loss have a cumulative impact on shoulder instability, and that these defects may engage in functional positions depending on their size, location, and orientation, potentially resulting in failure of stabilisation procedures. Determining which lesions pose a risk for engagement remains a challenge, with Itoi's 3DCT based glenoid track method and arthroscopic assessment being the accepted approaches at this time. The purpose of this study was to investigate the interaction of humeral and glenoid bone defects on shoulder engagement in a cadaveric model. Two alternative approaches to predicting engagement were evaluated; 1) CT scanning the shoulder in abduction and external rotation 2) measurement of Bankart lesion width and a novel parameter, the intact anterior articular angle (IAAA), on conventional 2D multi-plane reformats.

Hill-Sachs and Bony Bankart defects of varying size were created in 12 cadaveric upper limbs, producing 45 bipolar defect combinations. The shoulders were assessed for engagement using cone beam CT in various positions of function, from 30 to 90 degrees of both abduction and external rotation. The humeral and glenoid defects were characterised by measurement of their size, location, and orientation. The abduction external rotation scan and 2D IAAA approaches were compared to the glenoid track method for predicting engagement.

Engagement was predicted by Itoi's glenoid track method in 24 of 45 specimens (53%). The abduction external rotation CT scan performed at 60 degrees of glenohumeral abduction (corresponding to 90 degrees of abduction relative to the trunk) and 90 degrees of external rotation predicted engagement accurately in 43 of 45 specimens (96%), with sensitivity and specificity of 92% and 100% respectively. A logistic model based on Bankart width and IAAA provided a prediction accuracy of 89% with sensitivity and specificity of 91% and 87%. Inter-rater agreement was excellent (Kappa = 1) for classification of engagement on the abduction external rotation CT, and good (intraclass correlation = 0.73) for measurement of IAAA.

Bipolar lesions at risk for engagement can be identified using an abduction external rotation CT scan at 60 degrees of glenohumeral abduction and 90 degrees of external rotation, or by performing 2D measurements of Bankart width and IAAA on conventional CT multi-plane reformats. This information will be useful for peri-operative decision making around surgical techniques for shoulder stabilisation in the setting of bipolar bone defects.


V. Tjong C. Cogan M. Knesek R. Nair C. Kahlenberg M.A. Terry

Previous authors have suggested that the analgesic effects of intra-articular morphine may be beneficial. Clonidine has been found to potentiate the analgesic effect of morphine. Following knee arthroscopy, morphine has demonstrated equivocal effect in comparison to bupivicaine for analgesia while circumventing the issue of chondrotoxicity. There have been no studies evaluating the effect of intra-articular morphine following hip arthroscopy. The purpose of this study was to evaluate the efficacy of intra-articular morphine in combination with clonidine on pain and narcotic consumption following hip arthroscopy surgery for femoroacetabular impingement.

A retrospective review was performed on 43 patients that underwent hip arthroscopy between September 2014 and May 2015 at our institution for femoroacetabular impingement. All patients received preoperative Celebrex and Tylenol per our anesthesia protocol, and 22 patients received an additional intra-articular injection of 10 mg morphine and 100 mcg of clonidine at the conclusion of the procedure. Narcotic consumption, duration of anesthesia recovery, and perioperative pain scores were compared between the two groups.

We found that patients who received intra-articular morphine and clonidine used significantly less opioid analgesic in the PACU, with 23 mEq of morphine equivalents required in the intra-articular morphine and clonidine group compared to 40 mEq of opiod equivalents in the non-injection group (p=0.0259). There were no statistically significant differences in time spent in recovery prior to discharge or in VAS pain scores recorded immediately post-operatively and at one hour following surgery.

In conclusion, we found that an intraoperative intra-articular injection of morphine and clonidine significantly reduced the amount of narcotic requirement following hip arthroscopy. We do believe that there may be significant benefits to this, including less systemic effects from overall narcotic usage in the perioperative period. Our study demonstrated a beneficial effect of intra-articular morphine that may help with overall pain improvement, less narcotic consumption, and improved patient satisfaction following outpatient hip arthroscopy. This study provides the foundation for future research currently being conducted in a randomised-control setting.


R.M. Degen D.H. Nawabi K.G. Fields A. McLawhorn A.S. Ranawat E.L. Sink B.T. Kelly

The outcomes of hip arthroscopy in the treatment of dysplasia are variable. Historically, arthroscopic treatment of severe dysplasia (lateral center-edge angle [LCEA] < 18°) resulted in poor outcomes and iatrogenic instability. However, in milder forms of dysplasia, favorable outcomes have been reported. The purpose of this study was to compare outcomes following hip arthroscopy for femorocetabular impingement (FAI) in borderline dysplastic (BD) patients compared with a control group of non-dysplastic patients.

Between March 2009 and July 2012, a BD group (LCEA 18°–25°) of 46 patients (55 hips) was identified. An age and sex-matched control group of 131 patients (152 hips) was also identified (LCEA 25°–40°). Patient-reported outcome scores, including the Modified Harris Hip Score (mHHS), the Hip Outcome Score-Activity of Daily Living (HOS-ADL), the Sport-specific Subscale (HOS-SSS), and the International Hip Outcome Tool (iHOT-33), were collected pre-operatively, at 1, and 2 years.

The mean LCEA was 22.4 ± 2.0° (range, 18.4°–24.9°) in the BD group and 31.0 ± 3.1° (range, 25.4°–38.7°) in the control group (p<0.001). The mean preoperative alpha angle was 66.3 ± 9.9° in the BD group and 61.7 ± 13.0° in the control group (p=0.151). Cam decompression was performed in 98.2% and 99.3% of cases in the BD and control groups. Labral repair was performed in 69.1% and 75.3% of the BD and control groups respectively, with 100% of patients having a complete capsular closure performed in both groups. At a mean follow-up of 31.3 ± 7.6 months (range, 23.1–67.3) in unrevised patients and 21.6 ± 13.3 months (range 4.7–40.6) in revised patients, there was significant improvement (p<0.001) in all patient reported outcome scores in both groups. Multiple regression analysis did not identify any significant differences between groups. Importantly, female sex did not appear to be a predictor for inferior outcomes. Two patients (4.3%) in the BD group and six patients (4.6%) in the control group required revision arthroscopy during the study period.

Favorable outcomes can be expected following the treatment of impingement in borderline dysplastics when labral refixation and capsular closure are performed, with comparable outcomes to non-dysplastic patients. Further follow-up in larger cohorts is necessary to prove the durability and safety of hip arthroscopy in this challenging group and to further explore potential gender-related differences in outcome.


P. Lodhia C. Gui S. Chandrasekaran C. Suarez-Ahedo B.G. Domb

We present a prospective two-year follow-up study of 1038 hip arthroscopies performed at a high volume tertiary referral centre for hip preservation. We feel that this manuscript is both pertinent and timely due to the advances in the field of hip preservation.

We used four validated patient-reported outcome (PRO) scores along with the visual analog scale (VAS) and patient satisfaction scores to assess preoperative and postoperative outcomes in all patients undergoing hip arthroscopy. We divided the entire cohort into patients undergoing primary and revision hip arthroscopies. We found a statistically significant improvement from preoperative to two-year postoperative PRO scores in the two subgroups. We also found a significant difference in the PRO scores at three months, one year, and two years postoperatively between the primary and revision subgroups. The revision subgroup had inferior VAS and patient satisfaction compared to the primary subgroup, however these results were not significant. The conversion to total hip arthroplasty/hip resurfacing (THA/HR) was 5.6% and 11.2% in the primary and revision subgroups, respectively. This resulted in a relative risk of 2.0 for conversion to THA/HR in the revision subgroup. We had a complication rate of 5.3 (only 0.5% of which were considered major) which was similar to that reported in the literature for hip arthroscopy.

The primary purpose was to perform a survival analysis in a large mixed cohort of patients undergoing hip arthroscopy at a high volume tertiary referral centre for hip preservation with minimum two-year follow-up. The secondary purpose was to compare clinical outcomes of primary versus revision hip arthroscopy.

From February 2008 to June 2012, data were prospectively collected on all patients undergoing primary or revision hip arthroscopy. Patients were assessed pre- and post-operatively with modified Harris Hip Score (mHHS), Non-Arthritic Hip Score (NAHS), Hip Outcome Score-Activities of Daily Living (HOS-ADL), and Hip Outcome Score-Sport Specific Subscales (HOS-SSS). Pain was estimated on the visual analog scale (VAS). Patient satisfaction was measured on a scale from 0 to 10.

There were a total of 1155 arthroscopies performed, including 1040 primary arthroscopies (926 patients) and 115 revision arthroscopies (106 patients). Of these, 931 primary arthroscopies (89.5%) in 824 patients (89.0%) and 107 revision arthroscopies (93.0%) in 97 patients (91.5%), were available for follow-up and included in our study. The mean change in patient reported outcome (PRO) scores at two-year follow-up in the primary subgroup was 17.4 for mHHS, 19.7 for HOS-ADL, 23.8 for HOS-SSS, 21.3 for NAHS, and −3.0 for VAS. The mean change in PRO scores at two-year follow-up in the revision subgroup was 13.4, 10.9, 16.1, 15.4, and −2.7, respectively. All scores improved significantly compared to pre-operatively (p<0.001). PRO scores were higher at all time points for the primary subgroup compared to the revision subgroup (p<0.05). Satisfaction was 7.7 and 7.2 for primary and revision subgroups, respectively. Of 931 primary arthroscopies, 52 (5.6%) underwent THA/HR. Of 107 revision arthroscopies, 12 (11.2%) underwent THA/HR. The relative risk of a THA/HR was 2.0 after revision procedures compared to primary procedures. The overall complication rate was 5.3%.

Hip arthroscopy showed significant improvement in all PRO, VAS, and satisfaction scores at two years postoperatively. Primary arthroscopy patients showed greater PRO scores and a trend towards greater VAS compared to the revision subgroup. The relative risk of a THA/HR was 2.0 after revision procedures compared to primary procedures.


O.R. Ayeni D. de SA K. Stephens M. Kuang N. Simunovic J. Karlsson

Health care facilities are major contributors of waste to landfills, with operating rooms estimated to assume 20–70% of this waste. With hip arthroscopy for femoroacetabular impingement (FAI) on the rise, it is important to understand its environmental impact and identify areas for greening practices. Given its minimally-invasive nature, we hypothesise overall arthroscopic waste per FAI patient case to be approximately 5 kg, with minimal biohazard waste. The purpose of this study was to determine the amount of waste produced in FAI procedures and understand the environmental impact of the procedure to aid us in developing greening practices.

A single surgeon waste audit (with descriptive statistics) of five FAI hip arthroscopy procedures – categorised by: 1) normal/landfill waste; 2) recyclable cardboards and plastics; 3) biohazard waste; 4) sharp items; 5) linens; and 6) sterile wrapping – was performed in April 2015.

The surgical waste (except laundered linens) from the five FAI surgeries totalled 47.4 kg, of which 21.7 kg (45.7%) was biohazard waste, 11.7 kg (24.6%) was sterile wrap, 6.4 kg (13.5%) was normal/landfill waste, 6.4 kg (13.5%) was recyclable plastics, and 1.2 kg (2.6%) was sharp items. There was an average of 9.4 kg (excluding laundered linens) of waste produced per procedure.

Considerable waste, specifically biohazard waste, is produced in FAI procedures with an average of 9.4 kg of waste produced per procedure, including 4.3 kg of biohazard waste. In Canada (population 35.7 million), approximately 18 800 kg of waste (8600 kg of biohazard waste) is produced from an estimated 2000 FAI procedures performed every year. Additional recycling programs, reducing surgical overage, and continued adherence to proper waste segregation will be helpful in reducing waste production and its environmental burden. An emphasis on “green outcomes” is also required to demonstrate environmental responsibility and effectively manage and allocate finite resources.


E. Amar D.B. Dillman B. Smith C.M. Coady I.H. Wong

Background: The results of arthroscopic anterior labral (Bankart) repair have been shown to have high failure rate in patients with significant glenoid bone loss. Several reconstruction procedures using bone graft have been described to overcome the bone loss, including autogenous coracoid transfer to the anterior glenoid (Latarjet procedure) as well as iliac crest autograft and tibial allografts. In recent years, trends toward minimally invasive shoulder surgery along with improvements in technology and technique have led surgeons to expand the application of arthroscopic treatment. Purpose: This study aims to perform a retrospective analysis of prospectively collected data to evaluate the clinical and radiological follow up of patient who underwent anatomic glenoid reconstruction using distal tibia allograft for the treatment of shoulder instability with glenoid bone loss at 1-year post operation time point.

Between December 2011 and January 2015, 55 patients underwent arthroscopic stabilisation of the shoulder by means of capsule-labral reattachment to glenoid ream and bony augmentation of glenoid bone loss with distal tibial allograft for recurrent instability of the shoulder. Preoperative and postoperative evaluation included general assessment by the western Ontario shoulder instability index (WOSI) questionnaire, preoperative and postoperative radiographs and CT scans.

Fifty-five patients have been evaluated with mean age of 29.73 years at time of the index operation. There were 40 males (mean age of 29.66) and 15 female (mean age of 29.93). Minimum follow up time was 12 months. The following adverse effects were recorded: none suffered from recurrent dislocation, 2 patients suffered from bone resorption but without overt instability, 1 patient had malunion due to screw fracture, None of the patients had nonunion. The mean pre-operative WOSI score was 36.54 and the mean postoperative WOSI score was 61.0.

Arthroscopic stabilisation of the shoulder with distal tibia allograft augmentation demonstrates promising result at 1year follow up.


M. Bhandari M. Khan O. Ayeni K. Madden A. Bedi A. Ranawat B. Kelly P. Sancheti L. Ejnisman E. Tsiridis

Femoroacetabular impingement (FAI) is a common cause of hip pain in the young adult. Uncertainty regarding surgical indications, outcome assessment, management preferences and perceptions of the literature exist. We conducted a large international survey assessing the perceptions and demographics of orthopaedic surgeons regarding FAI.

A survey was developed using previous literature, focus groups and a sample-to-redundancy strategy. The survey contained forty-six questions and was emailed to national orthopaedic associations and orthopaedic sports medicine societies for member responses. Members were contacted on multiple occasions to increase response rates.

Nine hundred orthopaedic surgeons from twenty national and international organisations completed the survey. Surgeons responded across 6 continents, 58.2 % from developed nations with 35.4 % having sports fellowship training. North American and European surgeons reported significantly greater exposure to hip arthroscopy during residency and fellowships in comparison to international respondents (48.0% vs. 44.5% vs. 25.6% respectively; p<0.001). Surgeons performing a higher volume of FAI surgery (over 100 cases per year) were significantly more likely to have practiced for more than 20 years (OR 1.91; 95% CI 1.01 to 3.63), be practicing at an academic hospital (OR 2.25; 95% CI 1.22 to 4.15), and have formal arthroscopy training (OR 46.17; 95% CI 20.28 to 105.15). High volume surgeons were over two-fold more likely to practice in North America and Europe (OR 2.26; 95% CI: 1.08 to 4.72).

The exponential rise in the diagnosis and surgical management for FAI appears to be driven largely by experienced surgeons in developed nations. Our analysis suggests that although FAI management is early in the innovation cycle we are at a tipping point towards wider uptake and utilisation. The results of this survey will help guide further research and study.


R.M. Degen G.H. Garcia C. Bui M. McGarry T.Q. Lee J.S. Dines

Acute Hill-Sachs (HS) reduction represents a potential alternative method to remplissage for the treatment of an engaging HS lesion. The purpose of this study is to biomechanically compare the stabilising effects of a acute HS reduction technique and remplissage in a complex instability model.

This was a comparative cadaveric study of 6 shoulders. For the acute HS lesion, a unique model was used to create a 30% defect, compressing the subchondral bone while preserving the articular surface in a more anatomic fashion. In addition, a 15% glenoid defect was made in all specimens. The HS lesion was reduced through a lateral cortical window with a bone tamp, and the subchondral void was filled with Quickset (Arthrex) bone cement to prevent plastic deformation. Five scenarios were tested; intact specimen, bipolar lesion, Bankart repair, remplissage with Bankart repair and HS reduction technique with Bankart repair. Translation, kinematics and dislocation events were recorded.

For all 6 specimens no dislocations occurred after either remplissage or the reduction technique. At 90 degrees of abduction and external rotation (ABER), anterior-inferior translation was 11.1 mm (SD 0.9) for the bipolar lesion. This was significantly reduced following both remplissage (5.1±0.7mm; p<0.001) and HS reduction (4.4±0.3mm; p<0.001). For anterior-inferior translation there was no significant difference in translation between the reduction technique and remplissage (p=0.91). At 90 degrees of ABER, the intact specimens average joint stiffness was 7.0±1.0N/mm, which was not significantly different from the remplissage (7.8±0.9 N/mm; p=0.9) and reduction technique (9.1±0.6 N/mm; p=0.50). Compared with an isolated Bankart repair, the average external rotation loss after also performing a remplissage procedure was 4.3±3.5 deg (p=0.65), while average ER loss following HS reduction was 1.1±3.3 deg (p=0.99). There was no significant difference in external rotation between remplissage and the reduction technique (p=0.83).

Similar joint stability was conferred following both procedures, though remplissage had 3.2-degree loss of ER in comparison. While not statistically significant, even slight ER loss may be clinically detrimental in overhead athletes. Overall, the acute reduction technique is a more anatomic alternative to the remplissage procedure with similar ability to prevent dislocation in a biomechanical model, making it a viable treatment option for engaging Hill-Sachs lesions.


P. Lodhia C. Gui T. Martin S. Chandrasekaran C. Suarez-Ahedo B.G. Domb

We present to you a match-controlled study assessing co-existing arthroscopic findings during hip arthroscopy in patients with an intraoperative diagnosis of a central acetabular osteophyte (CAO). We feel that this manuscript is both pertinent and timely.

Recent literature has described the entity of central acetabular impingement, in which an osteophyte of the cotyloid fossa impinges against the superomedial femoral head and fovea. The technique for central acetabular decompression has also been described to treat this entity. The primary purpose of this study was to report the prevalence of femoral head articular damage in a matched cohort of patients with and without central acetabular osteophyte (CAO) that was identified during hip arthroscopy. A secondary purpose was to identify the rates of co-existing intraarticular pathology in both patient groups.

Intraoperative data was collected prospectively on all patients undergoing hip arthroscopy at our institution between February 2008 to March 2015,. The inclusion criteria for this study were the presence of a CAO identified during hip arthroscopy for a labral tear and/or femoroacetabular impingement (FAI). Exclusion criteria were revision surgeries, Tönnis grade 1 and higher, and previous hip conditions such as Legg-Calves-Perthes disease, avascular necrosis, and prior surgical intervention. The matched cohort control group was selected based on gender, age within 5 years, body mass index (BMI), and workers' compensation claim, on a 1:3 ratio to patients who underwent hip arthroscopy for a labral tear and/or FAI and did not have a CAO.

The CAO group consisted of 126 patients, which were matched to 378 patients in the control group. The grades of femoral and acetabular chondral damage were significantly different between the two groups (p<0.01).

This study showed that patients with CAO had a significantly higher prevalence of femoral and acetabular chondral damage, size of articular defects on both surfaces and the prevalence of LT tears compared to matched controls.


A.S.E. Younger T. Daniels K. Wing M. Penner A. Veljkovic H. Wong P. Dryden M. Glazebrook

Patients often comment on swelling after foot and ankle surgery. However the relationship between swelling and outcome (pain and function) has not previously been outlined. A recent study by Pinsker and Daniels demonstrated that while swelling was rated as important by patients it was rarely included in outcome scores. The purpose of this paper was to determine the relationship between swelling and outcome after ankle fusion or replacement. A secondary purpose was to determine how this relationship changed in time, how swelling score changed before and after surgery, and determine differences in swelling score between total ankle replacement (TAR), open ankle arthrodesis (OAA) and arthroscopic ankle arthrodesis (AAA).

The COFAS prospective ankle arthritis database enrolls patients in 4 centers undergoing surgery by one of 6 surgeons since 2002. The MODEMS outcomes package from AAOS was used, with the validated ankle osteoarthritis score (AOS) score being used to assess outcomes in the pain and disability domains. The swelling score was indexed from 1 to 5, 1 being no swelling and 5 being severe swelling. Outcomes were recorded preoperatively and annually up to 2010. Statistical analysis was performed using 95% confidence intervals and correlations being determined using Pearson's correlation and r2 values.

The swelling score was correlated with AOS score with an r2 of 0.13 for postoperative patients. With the swelling score analysed categorically the difference of outcome was significant with a mean AOS score of 15.1 (CI 13.3 to 16.9) for a swelling score of 1, 23 (CI 21.7 to 24.9) for a swelling score of 2, 31 (CI 29.6 to 33.1) for 33.6 (CI 34.9 to 38.8) for 4, and 39 (CI 35.3 to 43.0) for 5. Swelling scores fell outside the 95% confidence intervals for all groups indicating that the AOS outcome of swelling score 5 patients was worse than the 4 group, 4 worse than 3, 3 worse than 2, and 2 worse than 1. Patients with swelling scores of 1 scored 24 points better than those with a swelling score of 5.

Swelling scores were the same preoperatively for total ankle arthroplasty, Arthroscopic and open fusions. However swelling scores were lower for arthroscopic fusions after surgery for all time periods at an average of 2.1 (CI 1.9 to 2.2), compared to total ankle arthroplasty (2.5, CI 2.4 to 2.6) and open ankle fusion (2.5, CI 2.4 to 2.6).

Swelling has a major relationship with outcome. Swelling may be the cause of poorer outcomes for open ankle fusion compared to arthroscopic. Swelling is an independent factor as swelling scores for TAA were higher compared to AAA despite similar outcomes. Arthroscopic surgery reduces the postoperative swelling. Methods to reduce swelling such as compression stockings, elevation, controlling bleeding may result in better outcomes. Minimising the invasiveness of surgery achieves this goal. Patient education about swelling, elevation and compression stockings would assist in these goals.


J.R. Rofaiel R.N. Katchky T. Newmarch R. Rampersaud J.T. Lau

In the current health care climate, there is an increasing focus on cost savings and resource management. As such, there is an emphasis on decreasing length of stay and performing surgery on an outpatient basis. Consequently, some patients will have unanticipated intra-operative or post-operative adverse events that will necessitate an unplanned post-operative hospital admission or a readmission after discharge. These unplanned admissions or readmissions represent an increased burden on health care systems and can cause cancellation of other scheduled procedures. The purpose of this study is to investigate whether pre-operative patient risk factors or intra-operative events could predict unplanned admission or readmission following discharge in patients undergoing either elective or emergency foot and ankle surgery.

Data was prospectively collected on a total of 889 patients. The patients were divided into two groups: patients without readmissions (N=791) and patients who had an unplanned admission or readmission (N=98). We also collected and analysed the following variables: age, gender, BMI, diabetes, ASA class, surgery start time, length of surgery, regional vs. general anesthetic, elective vs. trauma surgery and type of procedure. Logistic regression models were used to identify risk factors that could independently predict unplanned admissions or readmissions to hospital following foot and ankle surgery.

Factors that could be used to independently predict readmission were length of surgery (p 0.0154, Odds Ratio 1.004) and trauma surgery (0.0167; 1.978). For every 1-hour increase in length of surgery, the odds of unplanned admission/readmission increase by 1.27 times. The odds of patients undergoing surgery for acute traumatic injuries getting readmitted are 1.978 times higher than for elective surgery patients.

In conclusion, our study showed that pre-operative patient risk factors including BMI, diabetes, and ASA status were unable to predict whether patients would have an unplanned admission or readmission. The two factors that were able to predict whether patients would have an unplanned admission or readmission were length of the procedure and trauma surgery – both of which are not readily modifiable. Our results showed that in spite of institutional measures to ensure timely discharge, only 11% of patients required an unplanned admission or readmission.


R.N. Katchky J.R. Rofaiel T.K. Newmarch R. Rampersaud J.T. Lau

Lower-extremity orthopaedic procedures may be performed under either regional or general anaesthesia, or a combination of both techniques. There is a growing body of evidence supporting the benefits of regional anaesthesia, with meta-analyses of randomised controlled trials and registry data suggesting decreases in deep surgical site infections, thromboembolic events, cardiopulmonary complications and length of stay associated with use of regional anaesthesia. In patients undergoing foot and ankle surgery specifically, there is evidence demonstrating decreased post-operative pain, nausea, vomiting, opioid use and unplanned hospital admission. This supports an increased role for the use in regional anaesthesia in patients undergoing foot and ankle surgery. However, the type of anaesthetic used is dependent on surgeon, patient, anaesthesiologist and institutional factors. The purpose of this study is to investigate pre-operative factors that predict the type of anaesthetic used in patients undergoing foot and ankle surgery.

Data was collected prospectively on 888 patients undergoing foot or ankle surgery at a single institution. The primary method of anaesthesia for each procedure was recorded. Ten additional variables were recorded and analysed: age, BMI, gender, diabetes, ASA status, procedure length, procedure start time, elective vs. trauma procedure, primary vs. revision procedure and preoperative anticoagulation. Logistic regression modelling was performed to identify factors that independently predict the type of anaesthetic used.

General anaesthetic was employed in 280 patients (32%), and regional anaesthesia was the primary anaesthetic type used in 608 (68%). Logistic regression modelling demonstrated that factors that independently predict use of general anaesthetic include younger age (p<0.0001; Odds Ratio 0.97/year), male sex (0.0033; 1.618), procedure start time (0.0319; 1.066/hour) and length of procedure (<0.0001; 1.520/hour). Patients who underwent general anaesthetic had a mean length of procedure of 108 +/− 77 minutes, whereas patients provided with regional anaesthesia had a mean length of procedure 83 +/− 64 minutes.

With increasing evidence supporting the benefits of regional anaesthesia in patients undergoing lower extremity surgery, it is important to identify modifiable factors that contribute to patients receiving alternative treatments. Since later procedure start time was identified as an independent predictor of general anaesthetic use, there may be a role for identifying patients at increased risk of complications associated with general anaesthesia and scheduling earlier start times. Furthermore, while it is logical that extended length of procedure may be a contraindication to regional anaesthesia, the mean procedure time of 108 minutes in the general anaesthesia group indicates that many of these patients should still be considered candidates for regional anaesthesia.


A.S.E. Younger J.T. Ngai M.J. Penner A. Veljkovic K.J. Wing H. Wong

As an alternative to ankle replacement, ankle arthrodesis remains a mainstay in the treatment of end-stage arthritis. Arthroscopic techniques for ankle arthrodesis have more recently been developed, although there has been limited research exploring the cost of arthroscopic (AAA) versus open ankle arthrodesis (OAA), and comparing ankle fusions to replacement (TAA). We hypothesise that resource use after AAA will be lower than that after OAA, and both will be lower than TAA.

We performed a retrospective review of a prospectively collected database. The COFAS database was used to identify patients with >2 years of follow up who have undergone AAA, OAA or Hintegra TAA at St Paul's Hospital between 2003–2010. Ninety patients with TAA, 52 with AAA and 56 with OAA met our inclusion criteria. The following data were documented: patient demographics (age, gender, presence of diabetes, inflammatory arthritis or any smoking history), factors related to the index surgery (type of surgery, OR time, length of stay) and factors relating to the post-operative course (number of post-operative clinic visits, OR time for re-operations, length of stay for additional hospital admissions).

In terms of the index surgery, AAA required less initial OR time compared to either OAA or TAA. Initial length of hospital stay was significantly longer for both TAA and OAA, compared to AAA. Patients attended more follow-up visits after TAA or OAA compared to after AAA. In terms of additional OR time required, no significant differences were found among the groups. The most common reason for re-operation was infection or wound breakdown (38% of re-operations), followed by removal of hardware (15%). TAA also required significantly more additional days in hospital compared to either OAA or AAA. For all significant comparisons, p < 0.05. For each primary TAA, on average an additional one hour of surgery, three days in hospital and seven clinic visits were required on top of the cost factored for the primary arthroplasty. For each primary AAA, an additional four clinic visits, 23 minutes of revision surgery and one day in hospital were required. For each primary OAA, an average additional five clinic visits, three minutes of OR time, and 0.2 days of additional hospital stay occurred during follow up.

Using several measures of resource use, we find that arthroscopic ankle fusions compare favourably to both ankle replacements and open ankle fusions. We also show that resource utilisation measurements can be a useful surrogate for complications, and that resource utilisation can demonstrate the practical implications of complications for patients, surgeons and health care resources.


U. Sheth D. Wasserstein R. Moineddin R. Jenkinson H. Kreder S. Jaglal

Over the last decade, there has been a growing body of level I evidence supporting non-operative management (focused on early range of motion and weight bearing) of acute Achilles tendon ruptures. Despite this emerging evidence, there have been very few studies evaluating its uptake. Our primary objective was to determine whether the findings from a landmark Canadian trial assessing the optimal management strategy for acute Achilles tendon ruptures influenced the practice patterns of orthopaedic surgeons in Ontario, Canada over a 12-year time period. As a second objective we examined whether patient and provider predictors of surgical repair utilisation differed before and after dissemination of the landmark trial results.

Using provincial health administrative databases, we identified Ontario residents 18 years of age and older with an acute Achilles tendon rupture from April 2002 to March 2014. The proportion of surgically repaired ruptures was calculated for each calendar quarter and year. A time-series analysis using an interventional autoregressive integrated moving average (ARIMA) model was used to determine whether changes in the proportion of surgically repaired ruptures were chronologically related to the dissemination of results from a landmark Canadian trial by Willits et al. (first quarter, 2009). Spline regression was then used to independently identify critical time-points of change in the surgical repair rate to confirm our findings. A multivariate logistic regression model was used to assess for differences in patient and provider predictors of surgical repair utilisation before and after the landmark trial.

From the second quarter of 2002 to the first quarter of 2010 the surgical repair rate remained constant at ∼21%, however, by the first quarter of 2014 it fell to 6.5%. A statistically significant decrease in the rate of surgical repair (P<0.001) was observed after the results from a landmark Canadian trial were presented at a major North American conference (February 2009). Both teaching and non-teaching hospitals demonstrated a decline in the surgical repair rate over the study period, however, only the decrease seen at non-teaching hospitals was found to be significantly associated with the dissemination of landmark trial results (P<0.001). All other predictors of surgical repair utilisation remained unchanged in the before-and-after analysis with the exception of patients 30 years of age and younger having a higher odds of undergoing surgical repair after the trial when compared to those 51 years of age and older.

The current study demonstrates that large, well-designed randomised trials, such as the one conducted by Willits et al. can significantly change the practice patterns of orthopaedic surgeons. Moreover, the decline in surgical repair rate observed at both teaching and non-teaching hospitals suggests both academic and non-academic surgeons readily incorporate high quality evidence in to their practice.


A. Dodd R. Khan E. Pinsker T. Daniels

End-stage ankle arthritis (ESAA) is a debilitating disease that does not affect all individuals equally. Gender differences have been identified in patients with end-stage hip and knee arthritis and have stimulated research to explain these findings. The present study was undertaken to examine if gender has a significant effect on pre-operative disability and post-operative outcomes in patients with ESAA.

Patients undergoing ankle arthrodesis (AA) or total ankle replacement (TAR) with minimum 2-year follow-up were identified in the Canadian Orthopaedic Foot and Ankle Society prospective ankle reconstruction database. Demographic data, revision data, patient satisfaction questionnaires, and outcome data using the Ankle Osteoarthritis Scale (AOS) and Short-form 36 (SF-36) health survey were collected.

TAR: 384 patients were included, with 198 females and 186 males. Patient BMI, comorbidities, and duration of follow-up were similar between groups. Males were slightly older at the time of surgery (65.1 vs 62.4 years, p=0.01)). The most common etiology was post-traumatic arthritis for both genders, however females had a higher rate of rheumatoid arthritis (17% vs 5%, p=0.001). Implant types included STAR, Hintegra, and Mobility, and were similar between groups. Preoperatively females had higher rates of pain and disability, demonstrated by lower SF-36 physical component scores (PCS) (31.0 vs 34.5, p<0.001), and higher AOS pain (54.7 vs 51.1, p=0.05) and AOS disability scores (66.5 vs 59.6, p<0.001). Postoperatively, both groups had significant improvement in PCS, AOS pain, and AOS disability scores. Females, however, continued to demonstrate lower PCS scores (38.3 vs 41.9, p<0.001) and higher AOS disability (31.0 vs 25.8, p=0.02) than males. Regression analysis found that preoperative PCS, gender, age, and arthritis etiology all had a significant impact on postoperative PCS scores, with preoperative PCS scores having the largest impact. Preoperative AOS pain and disability scores had the largest impact on postoperative AOS pain and disability scores, respectively. Gender had no significant impact on AOS pain and disability scores postoperatively. Patient satisfaction was similar between males and females postoperatively. Secondary surgery was performed in 13.6% of females and 16.1% of males. Five males and five females underwent revision to arthrodesis.

In patients with ESAA, females tend to have higher pre-operative levels of pain and disability compared to males, which persists post-operatively. This is consistent with the hip and knee arthroplasty literature. This finding may be due to females undergoing surgery at more advanced disease states, arthritis etiology, referral bias, or treatment bias. Both males and females have significant and similar degrees of improvement in pain and disability scores after TAR, and reoperation rates and patient satisfaction rates are similar despite the apparent disparity in outcomes.


N.M. Gosselin-Papadopoulas Y. Laflamme J. Menard D. Rouleau S. Leduc J. Davies M.L. Nault

Reoperations may be a better way of tracking adverse outcomes than complications. Repeat surgery causes cost to the system, and often indicate failure of the primary procedure resulting in the patient not achieving the expected improvement in pain and function. Understanding the cause of repeat surgery at the primary site may result in design improvements to implants or improvements to fusion techniques resulting in better outcomes in the future. The COFAS group have designed a reoperation classification system. The purpose of this study was to outline the inter and intra observer reliability of this classification scheme.

To verify the inter- and intra-observer reliability of this new coding system, six fellow ship trained practicing foot and ankle Orthopaedic surgeons were asked to classify 62 repeat surgeries from a single surgeons practice. The six surgeons read the operation reports in random order, and reread the reports 2 weeks later in a different order. Reliability was determined using intraclass correlation coefficients (ICC) and proportions of agreement. The agreement between pairs of readings (915 for inter observer for the first and second read – 61 readings with 15 comparisons, observer 1 with observer 2, observer 1 with observer 3, etc) was determined by seeing how often each observer agreed. This was repeated for the 366 ratings for intra observer readings (61 times 6).

The inter-observer reliability on the first read had a mean intra-class correlation coefficient (ICC) of 0.89. The range for the 15 comparisons was 0.81 to 1.0. Amongst all 1830 paired codings between two observers, 1605 (88%) were in agreement. Across the 61 cases, 45 (74%) were given the same code by all six observers. However, the difference when present was larger with more observers not agreeing. The inter-observer reliability test on the second read had a mean ICC of 0.94, with a range of 0.90. There were 43 (72%) observations that were the same across all six observers. Of all pairs (915 in total) there was agreement in 804 pairs for the first reading (88%) and disagreement in 111 (12%). For the second reading there was agreement in 801 pairs (86%) and disagreement in 114 (14%). The intra-observer reliability averaged an ICC value of 0.92, with a range of 0.86 to 0.98. The observers agreed with their own previous observations 324 times out of 366 paired readings (89% agreement of pairs).

The COFAS classification of reoperations for end stage ankle arthritis was reliable. This scheme potentially could be applied to other areas of Orthopaedic surgery and should replace the Claiden Dindo modifications that do not accurately reflect Orthopaedic outcomes. As complications are hard to define and lack consistent terminology reoperations and resource utilisation (extra clinic visits, extra days in hospital and extra hours of surgery) may be more reliable measures of the negative effects of surgery.


A.S.E. Younger M. Penner M. Glazebrook G. Goplen T. Daniels A. Veljkovic K. Lalonde K. Wing P. Dryden H. Wong

Reoperations may be a better way of tracking adverse outcomes than complications. Repeat surgery causes cost to the system, and often indicate failure of the primary procedure resulting in the patient not achieving the expected improvement in pain and function. Understanding the cause of repeat surgery at the primary site may result in design improvements to implants or improvements to fusion techniques resulting in better outcomes in the future. The COFAS group have designed a reoperation classification system. The purpose of this study was to outline the inter and intra observer reliability of this classification scheme.

To verify the inter- and intra-observer reliability of this new coding system, six fellow ship trained practicing foot and ankle Orthopaedic surgeons were asked to classify 62 repeat surgeries from a single surgeons practice. The six surgeons read the operation reports in random order, and reread the reports 2 weeks later in a different order. Reliability was determined using intraclass correlation coefficients (ICC) and proportions of agreement. The agreement between pairs of readings (915 for inter observer for the first and second read – 61 readings with 15 comparisons, observer 1 with observer 2, observer 1 with observer 3, etc) was determined by seeing how often each observer agreed. This was repeated for the 366 ratings for intra observer readings (61 times 6).

The inter-observer reliability on the first read had a mean intra-class correlation coefficient (ICC) of 0.89. The range for the 15 comparisons was 0.81 to 1.0. Amongst all 1830 paired codings between two observers, 1605 (88%) were in agreement. Across the 61 cases, 45 (74%) were given the same code by all six observers. However, the difference when present was larger with more observers not agreeing. The inter-observer reliability test on the second read had a mean ICC of 0.94, with a range of 0.90. There were 43 (72%) observations that were the same across all six observers. Of all pairs (915 in total) there was agreement in 804 pairs for the first reading (88%) and disagreement in 111 (12%). For the second reading there was agreement in 801 pairs (86%) and disagreement in 114 (14%). The intra-observer reliability averaged an ICC value of 0.92, with a range of 0.86 to 0.98. The observers agreed with their own previous observations 324 times out of 366 paired readings (89% agreement of pairs).

The COFAS classification of reoperations for end stage ankle arthritis was reliable. This scheme potentially could be applied to other areas of Orthopaedic surgery and should replace the Claiden Dindo modifications that do not accurately reflect Orthopaedic outcomes. As complications are hard to define and lack consistent terminology reoperations and resource utilisation (extra clinic visits, extra days in hospital and extra hours of surgery) may be more reliable measures of the negative effects of surgery.


E. Pinsker T. Inrig P. Daniels T.R. Daniels D.E. Beaton

Researchers and clinicians measuring outcomes following total ankle replacement (TAR) are challenged by the wide range of outcome measures used in the literature without consensus as to which are valid, reliable, and responsive in this population. This review identifies region- or joint-specific outcome measures used for evaluating TAR outcomes and synthesises evidence for their measurement properties.

A standard search strategy was conducted of electronic databases MEDLINE, EMBASE and CINAHL (to June 2015) to identify foot/ankle measures in use. A best evidence synthesis approach was taken to critically appraise measurement properties [COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN)] of identified measures. The review was restricted to English publications and excluded cross-cultural adaptations. Measurement properties collected from each article were coded for validity, reliability, responsiveness, or interpretability. Clinimetric evidence exists for identified measures tested in non-TAR populations, but were not the focus of this review.

The search identified 14 studies to include in the best evidence synthesis with 32 articles providing clinimetric evidence for eight of the measures (one CBO, seven PRO), however only five measures were tested in a TAR population (Foot Function Index, Ankle Osteoarthritis Scale, American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Scale [AOFAS], Foot and Ankle Outcome Score, Self-Reported Foot and Ankle Score). Five studies provided clinimetric evidence in a TAR population and their methodological quality was assessed: (1) Validity—two good quality studies examining different measures provide moderate evidence supporting construct validity (FFI, AOS, AOFAS self-reported items; SEFAS); (2) Reliability—two good quality studies examining different measures provide moderate evidence supporting internal consistency and test-retest reliability (FFI, AOS, AOFAS self-reported items; FAOS, SEFAS); (3) Responsiveness—three poor quality studies, thus unknown evidence for responsiveness; (4) Interpretability—two studies provide interpretability values (AOS, FFI, AOFAS self-reported items; AOS).

This review offers a basis for choosing the most appropriate instrument for evaluating TAR outcomes. Numerous outcome measures were identified with evidence supporting their use in populations with various foot/ankle conditions, but none have strong evidence supporting use in a TAR population. Measures must have adequate clinimetric properties in all patient groups in which they are applied. Evidence supporting or critiquing an instrument should not be based on studies with poor quality methodology, as identified by this review. Further testing in a TAR population would benefit identified measures with emphasis on adequate sample sizes, testing a priori hypotheses, and evaluating their content validity for a TAR population.


L. Leveille A. Erdman K. Jeans K. Tulchin-Francis L. Karol

The natural history of gait pattern change in children with spastic diplegia is a transition from toe walking to progressive hip and knee flexion with eventual crouch gait. This has been attributed to the adolescent growth spurt, progressive lever arm dysfunction, and iatrogenic weakening of the soleus with isolated tendo achilles lengthening (TAL). The relative contribution of TAL to the development of crouch gait is uncertain. The purpose of this study was to identify the frequency of crouch gait in spastic diplegic patients with and without history of prior TAL.

Patients with spastic diplegia greater than 10 years of age with instrumented gait analysis were reviewed. Exclusion criteria included diagnosis other than cerebral palsy, prior dorsal root rhizotomy, or incomplete past surgical history. Patients were divided into three groups: Group 1, no prior orthopaedic surgical intervention; Group 2, prior orthopaedic surgery without TAL; Group 3, prior orthopaedic surgery with TAL. Instrumented gait analysis data was analysed. Gait data were analysed using a single randomised limb from each patient.

One hundred and seventy-eight patients were identified: 39 in Group 1, 49 in Group 2, and 90 in Group 3. Mean time from TAL to gait analysis was 7.5 years (range 1.0–14.6 years). Mean age at TAL was 6.3 years (range 1.2–17.5 years). There was no significant difference in age, BMI, walking speed, or cadence between groups. Kinematic analysis showed no significant difference in mean stance phase maximum knee or ankle flexion between groups. There was no significant difference in frequency of increased mid stance knee flexion between groups (Group 1, 53.8%; Group 2 46.9%; Group 3, 43.3%, p=0.546). There was a trend towards increased frequency in excessive stance phase ankle dorsiflexion in Group 3 (60% Group 3 vs 46.2% Group 1, and 40% Group 2, p=0.071). Crouch gait (stance minimum hip flexion > 30, mid stance minimum knee flexion > 200, and stance maximum ankle dorsiflexion > 150) was seen with similar frequency in all groups (Group 1, 23.1%; Group 2, 18.4%; Group 3, 26.7%; p=0.544).

There is a trend towards increased frequency of excessive stance phase ankle dorsiflexion in spastic diplegic patients with prior TAL. However, no significant difference in frequency of crouch gait between patients with and without history of TAL was identified. Crouch gait is part of the natural history of gait pattern change in spastic diplegic patients independent of prior surgical intervention.


R. Pathy D.R. Sturnick J.S. Blanco E.R. Dodwell D.M. Scher

Fixation of tendon transfers about the foot in children typically involves creating a bone tunnel through which a suture is passed and tied over an external button. An internal suspension system, such as the Endobutton (Smith & Nephew) is an alternative fixation method which has demonstrated excellent fixation strength and minimal intraosseous tunnel displacement in various adult procedures. Application of the Endobutton technique has no risk of skin ulceration, does not require suture removal and may provide more secure fixation. The purpose of this study is to compare the biomechanical properties of the external button and Endobutton fixation techniques. Our primary outcome measure was intra-osseous displacement of the suture, during both static and dynamic loading, in cadaver feet.

Nine adult cadaver feet were utilised. A bone tunnel was drilled in the lateral cuneiform and #1 braided non-absorbable suture was passed through the tunnel. One end was secured to a carabiner to be attached to the materials testing system and the other to the fixation device. The external button and Endobutton fixation techniques were tested once in each cadaver, randomising the order of testing to minimise bias. Each fixation technique underwent static and dynamic cyclic loading. A custom Matlab script was used to process video and materials testing system data. The relative displacement of the suture within the bone tunnel, as a function of time and load magnitude, was recorded during static and dynamic cyclic loading. Both fixation groups were analysed and compared for statistical significance using a paired T-test and an alpha value of 0.05.

The Endobutton group had significantly less displacement within the bone tunnel, during both static and dynamic loading, than the external button. The average displacement during static loading was 0.42 mm for the Endobutton and 2.17 mm for the external button (p=0.0019). Similarly, during dynamic cyclic loading, the mean displacement was 0.32 mm for the Endobutton and 0.66 mm for the external button (p=0.0115).

The Endobutton internal suspension technique demonstrates significantly less displacement during static and dynamic loading than the external button, during biomechanical testing in cadaver feet. The Endobutton may provide superior fixation than the traditional external button technique for tendon transfers in children. In addition, this technique avoids the risk of skin ulceration from the button and the need for suture removal.


J. Napora G.H. Thompson A. Gilmore J.P. Son-Hing R.W. Liu

Unstable slipped capital femoral epiphysis (SCFE) has an increased incidence of avascular necrosis (AVN). The purpose of this study was to determine if early identification and intervention for AVN may help preserve the femoral head.

We retrospectively reviewed 48 patients (50 hips) with unstable SCFE managed between 2000 and 2014. Based on two different protocols during the same time period, 17 patients (17 hips) had a scheduled MRI between 1 and 6 months from initial surgery, with closed bone graft epiphysiodesis (CBGE) or free vascularised fibular graft (FVFG) if AVN was diagnosed. Thirty-one patients (33 hips) were evaluated by plain radiographs. Outcomes analysed were Steinberg classification and subsequent surgical intervention. We defined Steinberg class IVC as failure in treatment because all of the patients referred for osteotomy, arthoplasty, or arthrodesis in our study were grade IVC or higher.

Overall, 13 hips (26%) with unstable SCFE developed AVN. MRI revealed AVN in 7 of 17 hips (41%) at a mean of 2.5 months postoperatively (range, 1.0 to 5.2 months). Six hips diagnosed by MRI received surgical intervention (4 CBGE, 1 FVFG, and 1 repinning due to screw cutout) at a mean of 4.1 months (range, 1.3 to 7.2 months) postoperatively. None of the 4 patients treated with CBGE within two months postoperatively progressed to stage IVC AVN. The two patients treated after four months postoperatively both progressed to stage VC AVN. Radiographically diagnosed AVN occurred in 6 of 33 hips (18%) at a mean of 6.8 months postoperatively (range, 2.1 to 21.1 months). One patient diagnosed with stage IVB AVN at 2.4 months had screw cutout and received CBGE at 2.5 months from initial pinning. The remaining 5 were not offered surgical intervention. Five of the 6 radiographically diagnosed AVN, including the one treated with CBGE, progressed to stage IVC AVN or greater.

None of the 4 patients with unstable SCFE treated with CBGE within 2 months post pinning developed grade IVC AVN, while all patients treated with other procedures after 2 months developed IVC or greater AVN. Early detection and treatment of AVN after SCFE may alter the clinical and radiographic progression.


S.E. Nelson K. Rooks A. Dzus L. Allen

Developmental dysplasia of the hip (DDH) refers to a spectrum of anatomical abnormalities. Despite various screening programs, delayed diagnosis still occurs. Delayed cases are more difficult to treat and can have poorer outcomes. Rural address, low socioeconomic status, and ethnicity have recently been associated with late presentation. The objectives of this study were to examine the incidence of DDH, as well as factors associated with delayed presentation in Saskatchewan.

Retrospective review of paediatric orthopaedic records from the tertiary referral centre in Saskatchewan was completed from 2008–2014. Variables collected included age at presentation, sex, birth order, birth presentation, birth complications, laterality, family history of DDH, postal code and treatment. Socioeconomic and geographic indicators were determined from postal code using the 2011 National Household Survey. Population level variables included income, ethnic origin, distance from referral centre and education. Associations were examined with bivariate and multivariate analysis.

There were 108 new presentations of DDH; 34 cases presented after age 3 months. Demographic data showed 83.3% of cases were female, 48.1% involved the left hip, 17.2% had a positive family history, 57.1% were first born, and 27.9% were breech. An estimated 5.6% of patients were Aboriginal. The mean age at presentation was 199.7 days. 48% of cases lived in the same city as the referral center. Late presenting cases lived on average 46.19 km farther from the referral centre and had a lower mean population, percent of adults with post-secondary education and income. However, none of these were statistically significant. No significant associations were found within the demographic data.

Overall incidence of DDH was not estimated due to few cases from southern areas of the province presenting to the tertiary referral center. The estimated incidence of DDH in the Aboriginal population from our sample was lower than previously reported in the literature. This association may be related to earlier swaddling practices, rather than Aboriginal ethnicity. There was a trend toward lower socioeconomic indicators and an increased distance from the referral centre in cases of late presentation, in keeping with recent literature exploring these factors. This suggests there may be deficits in the current selective screening protocols in North America. The study is limited by the retrospective nature of the research and the population level data obtained for certain variables. Future research to collect prospective individual level data may help elucidate important associations. Also, identifying any additional cases would increase the power to detect significant associations with late presentation, and allow an accurate estimate of overall incidence.


L. Leveille O. Razi C. Johnston

With observed success and increased popularity of growth modulation techniques, there has been a trend towards use in progressively younger patients. Younger age at growth modulation increases the likelihood of complete deformity correction and need for implant removal prior to skeletal maturity introducing the risk of rebound deformity. The purpose of this study was to quantify magnitude and identify risk factors for rebound deformity after growth modulation.

We performed a retrospective review of all patients undergoing growth modulation with a tension band plate for coronal plane deformity about the knee with subsequent implant removal. Exclusion criteria included completion epiphysiodesis or osteotomy at implant removal, ongoing growth modulation, and less than one year radiographic follow-up without rebound deformity. Mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA), hip-knee-ankle angle (HKA), and mechanical axis station were measured prior to growth modulation, prior to implant removal, and at final follow-up.

Sixty-seven limbs in 45 patients met the inclusion criteria. Mean age at growth modulation was 9.8 years (range 3.4–15.4 years) and mean age at implant removal was 11.4 years (range 5.3–16.4 years). Mean change in HKA after implant removal was 6.9O (range 0O–23 O). Fifty-two percent of patients had greater than 5O rebound and 30% had greater than 10O rebound in HKA after implant removal. Females less than ten years and males less than 12 years at time of growth modulation had greater mean change in HKA after implant removal compared to older patients (8.4O vs 4.7O, p=0.012). Patients with initial deformity greater than 20O degrees had an increased frequency of rebound greater than 10O compared to patients with less severe initial deformity (78% vs 22%, p=0.002).

Rebound deformity after growth modulation is common. Growth modulation at a young age and large initial deformity increases risk of rebound. However, rebound does not occur in all at risk patients, therefore, we caution against routine overcorrection. Patients and their families should be informed about the risk of rebound deformity after growth modulation and the potential for multiple surgical interventions prior to skeletal maturity.


K. Smit C. Birch D. Sucato

Osteochondromas occur are most commonly in the distal femur, proximal tibia and fibula and the proximal humerus. There are no large studies focusing on the clinical presentation, management and outcome of treatment for patients with an osteochondroma involving the proximal fibula. The purpose of this study is to specifically understand the manifestation of the proximal fibular osteochondroma on the preoperative peroneal nerve function, and how surgical management of the osteochondroma affects function immediately postoperatively and at long-term followup.

This is an IRB-approved retrospective review of a consecutive series of patients with a proximal fibular osteochondroma (PFO) treated operatively at a single institution from 1990 to 2013. The medical record was carefully reviewed to identify demographic data, clinical data and especially the status of the peroneal function at various time points.

There were 25 patients with 31 affected extremities who underwent surgical excision of the PFO at an average age of 12.4 years (range 3.0–17.9 years). There were 16 males and 9 females. The underlying diagnosis was isolated PFO in 2(8%) patients and multiple hereditary exostosis (MHE) in 23(92%) patients. Preoperatively, 9 (29%) had a foot drop and 22 (71%) did not. Those with preoperative foot drop underwent surgery at a younger age (9.1 vs 13.8 years) (p<0.004). Five of the nine (55.5%) had complete resolution, three (33.3%) had improvement, and one (11.1%) persisted postoperatively and required AFO. Of the 22 who were normal preoperatively, 5 (22.7%) developed a postoperative foot drop-three (60%) completely resolved, 1 (20%) improved, and 1 (20%) persisted and was found to have a transected nerve at exploration. In total, 23 of the 25 (92%) patients who had a PFO excision, had a normal or near-normal peroneal nerve function including those who had poor function preoperatively.

A proximal fibular osteochondroma can result in a high incidence of peroneal nerve dysfunction prior to any treatment, but responds the majority of the time to surgical intervention with removal of the osteochondroma. For those who have normal preoperative function, 1 in 4 will develop a postoperative foot drop but nearly all improve spontaneously unless iatrogenic injured.


D.C. Peterson S.H. Hendy D. de SA K. Ainsworth O.R. Ayeni N. Simunovic

To determine if there are osteochondritis dissecans (OCD) lesions of the knee that are so unstable on MRI that they are incapable of healing without operative intervention. A secondary objective was to determine the ability of orthopaedic residents to accurately grade OCD lesions according to the Kijowski criteria of stable and unstable.

A retrospective review was performed of patients who had femoral condyle OCD lesions from 2009-present. Only patients with open growth plates and serial MRIs were included. Each MRI was classified according to the Kijowski classification by a junior orthopaedic surgery resident as well as an MSK trained radiologist. A weighted kappa value was used to assess the inter-rater agreement.

The final analysis included 16 patients (17 knees) with 49 MRI's. The weighted kappa agreement between reviewers for overall lesion stability was moderate (0.570 [95% CI 0.237–0.757]). The initial MRI lesion was graded as stable in 59% (10/17) of the knees. Two of these 10 knees became unstable during the study period, however, both stabilised again on subsequent MRIs, one with surgery and the other without surgery. The initial MRI was graded as unstable in 41% (7/17) of the knees. Two of the seven knees (29%) later demonstrated MRI evidence of lesion stability without surgical intervention.

The most important finding in this study was the ability of unstable OCD lesions on MRI to heal without operative intervention. The ability of an orthopaedic surgery resident to grade these lesions on MRI was moderate.


E. Schaeffer C. Price K. Mulpuri

Laterality and bilaterality have been reported as prognostic variables in DDH outcomes. However, there is little clarity across the literature on the reporting of laterality in developmental dysplasia of the hip (DDH) due to the variability in severity of the condition. It is widely accepted that the left hip is most frequently affected; however, the true incidence of unilateral left, unilateral right and bilateral cases can be hard to quantify and compare across studies. The purpose of this study was to examine laterality accounting for graded severity in a multicentre, international prospective observational study of infants with hip dysplasia in order to demonstrate the complexity of this issue.

A multicentre, prospective database of infants diagnosed with DDH between the ages of 0 and 18 months was analysed from 2010 to April 2015. Patients less than six months were enrolled in the study if at least one hip was frankly dislocated. Patients between 6 and 18 months were enrolled if they had any form of hip dysplasia. Each hip was classified as reduced, dysplastic, dislocatable/subluxable, dislocated reducible or dislocated irreducible. Baseline diagnosis was used to classify patients into a graded laterality category accounting for hip status within the DDH spectrum.

A total of 496 patients were included in the analysis; 328 were <6 months old at diagnosis and 168 were between 6 and 18 months old. Of these patients, 421 had at least one frankly dislocated hip. Unilateral left hip dislocations were most common, with 223 patients, followed by unilateral right and bilateral dislocations with 106 and 92 respectively. Stratifying these patients based on status of the contralateral hip, 54 unilateral left and 31 unilateral right dislocated patients also had a dysplastic or unstable contralateral hip. There were significantly fewer bilateral patients in the 6–18 month group (p=0.0005). When classifying laterality by affected hip, bilaterality became the predominant finding, comprising 42% of all patients.

The distribution of unilateral left, unilateral right and bilateral cases was greatly impacted by the method of classification. Distinct patterns were seen when considering dislocated hips only, or when considering both dislocated and dysplastic/unstable hips. Findings from this multicentre prospective study demonstrate the necessity to account for the graded severity in hip status when reporting DDH laterality. In order to accurately compare laterality across studies, a standardised, comprehensive classification should be established, as contralateral hip status may impact prognosis and treatment outcomes.


K. Mulpuri S. Miller E. Schaeffer M. Juricic K. Hesketh

Hip displacement is the second most common deformity in children with cerebral palsy (CP). A displaced, and particularly a dislocated hip, can have significantly adverse effects on an individual. Surgical intervention to correct progressive hip displacement or dislocation is recommended for children with CP. Success of surgical intervention is often described using radiological outcomes. There is evidence that surgical treatment for displaced or dislocated hips decreases pain and hip stiffness and improves radiological outcomes. However, there is no information in the literature regarding the impact of surgical treatment on the health related quality of life (HRQOL) in these children. The aim of our study was to examine the impact of surgical treatment of hip displacement or dislocation on HRQOL in children with CP.

This prospective longitudinal cohort study involved children attending a tertiary care hospital orthopaedic department. Children with CP between the ages of 4 and 18 years, with hip displacement/dislocation, defined as a Reimer's migration percentage (MP) of >40% on a pre-operative x-ray, and undergoing surgical reconstruction were eligible for inclusion. Quality of life was measured pre-operatively and post-operatively using the CPCHILD Questionnaire.

Twelve patients (one child was GMFCS level III, 4 were level IV, and 7 were level V), aged 4.0 to 17.3 years, were assessed pre-operatively and then again at least six months post-operatively. All underwent unilateral (5) or bilateral (7) reconstructive hip surgery. The migration percentage of hips undergoing reconstruction was reduced by an average of 52% (9–100%). The average change in CPCHILD score showed an increase of 6.4 points [95% CI: −1.4–14.2].

In this pilot study, no significant change was noted in HRQOL following reconstructive hip surgery, despite a marked reduction in Reimer's MP. However, only 4 of 12 parents reported that their child had daily pain pre-operatively. A larger sample size will be required to draw more accurate conclusions from these findings. There is an evident need for a multicentre study examining this issue in a larger patient population in order to determine the long-term impact of different hip interventions on quality of life in children with CP.


E. Schaeffer N. Quader K. Mulpuri A. Cooper A. Hodgson R. Abugharbieh

Ultrasound (US) is the standard imaging modality used to screen for developmental dysplasia of the hip in infants. Currently, radiologists or orthopaedic surgeons review scan images and judge them to be adequate or inadequate for interpretation. If considered adequate, diagnostic dysplasia metrics are determined; however, there is no standardised method for this process. There is significant inter-observer variability in this manual process which can affect misdiagnosis rates. To eliminate this subjectivity, we developed an automatic method to identify adequate US images and extract dysplasia metrics. The purpose of this study was to validate the efficacy of this automatic method by comparing results with observer-determined dysplasia metrics on a set of US images.

A total of 693 US images from scans of 35 infants were analysed. Trained clinicians at a single institution labeled each image as adequate or inadequate, and subsequently measured alpha and beta angles on adequate images to diagnose dysplasia. We trained our image classifier on random sets of 415 images and used it to assess the remaining 278 images. Alpha and beta angles were automatically estimated on all adequate images. We compared the manual and automatic methods for discrepancies in adequacy determination, metric variability and incidences of missed early diagnosis or over-treatment.

There was excellent agreement between the automatic and manual methods in image adequacy classification (Kappa coefficient = 0.912). On each adequate US image, alpha and beta angle measurements were compared, producing mixed levels of agreement between methods. Mean discrepancies of 1.78°±4.72° and 8.91°±6.437° were seen for alpha and beta angles, respectively. Standard deviations of the angle measures across multiple images from a single patient scan were significantly reduced by the automatic method for both alpha (p<0.05) and beta (p<0.01) angles. Additionally, the automatic method classified three hips (two patients) as Graf type II and two hips (two patients) as type III, while the manual method classified them as type I and II, respectively. Both cases flagged as type III patients by the automatic system subsequently failed Pavlik harness treatment and were booked for surgery.

The automatic method produced excellent agreement with radiologists in scan adequacy classification and significantly reduced measurement variability. Good agreement between methods was found in Graf classification. In instances of disagreement, subsequent clinical findings seemed to support the classification of the automatic method. This proposed method presents an alternative automatic, near-real-time analysis for US images that may potentially significantly improve dysplasia metric reliability and reduce missed early diagnoses without increasing over-treatment.


L. Phillips A. Aarvold S. Carsen C. Alvarez

Forearm deformity is common in Hereditary Multiple Exostoses, for which multiple surgical treatments exist. Acute ulnar lengthening has been described in the literature, though in small numbers and not independent of adjunctive procedures. We hypothesise that acute ulnar lengthening as a primary procedure is safe and effective in correcting forearm deformity.

Seventeen ulnas in 13 patients had acute ulnar lengthening for HME associated forearm deformity, over an eight-year period. Radiographic parameters were assessed and compared preoperatively and postoperatively. Mean follow-up was 27 months. Complications and revisions were noted.

The mean pre-operative ulnar variance, 12.4mm (range 6.1 – 16.5), was significantly reduced post-operatively to a mean 4.6mm (p=<0.00001). A significant acute difference was achieved in carpal slip, (mean change of −2.2mm, p=0.02) but no significant change was seen with regard to radial bowing (p=0.98) or radial articular angle (p=0.74). There were three episodes of recurrence requiring revision. There were no major complications.

Significant radiographic improvements in forearm and wrist alignment were seen with acute ulnar lengthening. Complications were infrequent. Recurrence rates in the skeletally immature patients are comparable to that reported with gradual lengthening techniques. Acute ulnar lengthening for forearm deformity associated with HME, has been demonstrated to be a safe, reproducible and effective surgical procedure.


L.A. Sims G.H. Johnston S.A. Stewart

Distal ulna fractures (DUF) are commonly associated with distal radius fractures (DRF). Recent evidence suggests that the presence and type DUFs may impact the outcomes of associated healing distal radius fractures. There is currently no standardised and validated classification system for characterising distal ulna fractures. The purpose of this study was to assess the validity of our newly created inclusive classification system for distal ulna fractures, shown to influence distal radius fracture outcomes in a previous study.

A classification system for distal ulna fractures was devised based on fracture pattern and location. Type 1 fractures were those in the ulnar styloid, with type 1a involving its apex and Type 1b being in the body of the styloid; Type 2 fractures are proximal to the styloid and involve the ulnar fovea, with type 2t adopting a transverse pattern and type 2o an oblique pattern; Type 3 fractures involve the ulnar head; and type 4 fractures were those proximal to the head, with 4n being through the neck (including the physeal scar) and 4s involving the distal shaft. A questionnaire was distributed to all members of the Canadian Orthopaedics Association in both French and English, asking participants to evaluate 29 radiographic images of distal ulnar fractures. Only one answer was deemed to be correct for all but one radiograph, while for one radiograph there were three fracture types to be identified.

There were 129 respondents to the questionnaire. For Type 1a fractures, of the 606 radiographs evaluated 90% answered correctly and 73% of the incorrect answers identified a Type 1b fracture pattern. For Type 1b fractures, of 600 radiographs, 83% were answered correctly, the incorrect answers including Types 1a and 2t fracture types. For Type 2t fractures, of 593 radiographs, 76% were answered correctly, and 90% of the incorrect answers identified a Type 1b fracture pattern. For Type 2o fractures, of 716 radiographs, 87% were answered correctly, and 91% of the incorrect answers were identified as either Type 4n or 2t. For Type 4n fractures, of the 465 radiographs evaluated 84% answered correctly and 80% of the incorrect answers identified a Type 4s fracture pattern. For Type 4s fractures, of the 355 radiographs evaluated 99% answered correctly and 100% of the incorrect answers identified a Type 4n fracture pattern. The results will guide the authors to further distinguish between the definitions of Types 1b and 2t, and 4n and 4s.

The Canadian orthopaedic community has demonstrated how readily they can reproduce this new classification system, previously shown to be predictive of radiographic outcomes for the associated distal radius fractures. This new classification is an inclusive and simple way of characterising these fractures with high reliability. This provides treating physicians with a uniform way of describing these fractures, useful both in predicting outcomes and conducting future research.


S. Lalonde D. Pichora S. Zakani

Cadaveric specimens that have been fresh-frozen and then thawed for use have historically been considered to be the gold standard for biomechanical studies and the closest surrogate to living tissue. However, there are notable issues related to specimen rapid decay in the thawed state as well as infectious hazard to those handling the specimens. Cadaveric specimen preparation using a new phenol-based soft-embalmed method has shown considerable promise in preserving tissue in a prolonged fresh-like state while mitigating the infection risk. In this study, we evaluated the ability of soft-embalmed specimens to replace fresh-frozen specimens in the biomechanical study of flexor tendon repair.

An ex-vivo study was conducted on six cadaveric hands in both a fresh-frozen, thawed state and following embalming with a phenol-based solution. Six different combinations of flexor digitorum profundus (FDP) tendons, from D2 to D5, and flexor pollicis longus (FPL) tendons were used to create two groups of similar composition with 15 tendons each, one group to be tested fresh and the other following embalming. A 5cm length of each flexor tendon was harvested from zone 2 and transversely cut at the mid-section. A modified-Kessler repair was performed on each specimen using 4–0 Fiberwire, with two core sutures and 1cm purchase on each end. Incisions were closed with a running stitch to prepare the specimen for embalming. The same protocol was used to repair and harvest the second group of tendons one month following the perfusion of a phenol-based solution through the vasculature of the hand and forearm. Tendon repair biomechanics were characterised through a ramp loading to failure (rate 1mm/sec), incorporating the 12 mm travel distance of the testing machine. A video-extensometry technique was used to validate machine recordings for the repair site for force at the 2mm gap distance, the ultimate strength, and the mode of failure. Characteristics of the two groups were tested for equivalency using inferential confidence intervals (ICI).

Both fresh and embalmed groups were indistinguishable in both force at 2mm gap (fresh 17.9±4.7N; embalmed 18.1±5.1) and ultimate strength (fresh 43.93±10.0; embalmed 43.7±9.4). With the exception of one specimen with complete suture pull-out, all specimens exhibited partial pull-out as the final mode of failure.

Our study demonstrated that tendon repair characteristics of phenol-embalmed specimens were equivalent to fresh specimens. Post-mortem chemical preservation can indeed preserve both visual and biomechanical characteristics of soft tissues. This study opens new avenues in support of the use of embalmed specimens in medical curricula and surgical training.


K. Mozaffarian H.R. Zemoodeh M. Zarenezhad M. Owji

In combined high median and ulnar nerve injury, transfer of extensor digiti minimi (EDM) and extensor carpi ulnaris (ECU) nerve branches to restore intrinsic hand function is previously described. A segment of nerve graft is required in this operation. The aim of this study was to evaluate the feasibility of using the sensory branch of radial nerve (SRN) as an “in situ vascular nerve bridge'” (IVNB) instead of sural nerve graft.

Twenty fresh cadavers were dissected. In proximal forearm incision, the feasibility of transferring the EDM/ECU branches to the distal stump of transected SRN was evaluated. In distal forearm incision, the two distal branches of the SRN were transected near the radial styloid process to determine whether transfer of the proximal stumps of these branches to the motor branches of the median (MMN) and ulnar (MUN) nerves is possible. The number of axons in each nerve was determined.

The size of the dissected nerves and their location demonstrate that tension free nerve coaptation is easily possible in both proximal and distal incisions.

Utilisation of the SRN as an IVNB instead of the conventional sural nerve graft has some advantages. Firstly, the sural nerve graft is a single branch and could be sutured to either the MMN or MUN, whereas the SRN has two terminal branches and can address both of them. Secondly, the IVNB has live Schwann cells and may accelerate the regeneration. Finally, this IVNB does not require leg incision and could be performed under regional anesthesia. The SRN as an IVNB is a viable option which can be used instead of conventional nerve graft in some brachial plexus or high median and ulnar nerve injuries when restoration of intrinsic hand function by transfer of EDM/ECU branches is attempted.


H.L. Stoesser C. Padmore M. Nishiwaki B. Gammon G.D. Langohr E. Lalone J.A. Johnson G.J.W. King

Wrist motion is achieved primarily via rotation at the radiocarpal and midcarpal joints. The contribution of each carpal bone to total range of motion has been previously investigated, although there is no consensus regarding the influence of each structure to global wrist motion. The objective of this comprehensive in-vitro biomechanical study was to determine the kinematics of the capitate, scaphoid and lunate during unconstrained simulated wrist flexion-extension. In addition, this study examined the effect of motion direction (i.e. flexion or extension) on the kinematics and contribution of the carpal bones.

Seven fresh frozen cadaveric upper limb specimens (age: 67±18 yrs) were amputated mid-humerus, and the wrist flexors/extensors were exposed and sutured at their musculotendinous junctions. Each specimen was mounted on a wrist motion simulator in neutral forearm rotation with the elbow at 90° flexion. Passive flexion and extension motion of the wrist was simulated by moving a K-wire, inserted into the third metacarpal, through the flexion/extension motion arc at a speed of ∼5 mm/sec under muscle tone loads of 10N. Carpal kinematics were captured using optical tracking of bone fixated markers. Kinematic data was analysed from ±35° flexion/extension.

Scaphoid and lunate motion differed between wrist flexion and extension, but correlated linearly (R‸2=0.99,0.97) with capitate motion. In wrist extension, the scaphoid (p=0.03) and lunate (p=0.01) extended 83±19% & 37±18% respectively relative to the capitate. In wrist flexion, the scaphoid (p=1.0) and lunate (p=0.01) flexed 95±20% and 70±12% respectively relative to the capitate. The ratio of carpal rotation to global wrist rotation decreased as the wrist moved from flexion to extension. The lunate rotates on average 46±25% less than the capitate and 35±31% less than the scaphoid during global wrist motion (p=0.01). The scaphoid rotates on average 11±19% less than the capitate during wrist flexion and extension (p=0.07). There was no difference in the contribution of carpal bone motion to global wrist motion during flexion (p=0.26) or extension (p=0.78).

The capitate, lunate and scaphoid move synergistically throughout planar motions of the wrist. Our study found that both the scaphoid and lunate contributed at a greater degree during wrist flexion compared to extension, suggesting that the radiocarpal joint plays a more critical role in wrist flexion. Our results agree with previous studies demonstrating that the scaphoid and lunate do not contribute equally to wrist motion and do not function as a single unit during planar wrist motion. The large magnitude of differential rotation observed between the scaphoid and lunate may be responsible for the high incidence of scapholunate ligament injuries relative to other intercarpal ligaments. An understanding of normal carpal kinematics may assist in developing more durable wrist arthroplasty designs.


C.E. Padmore H. Stoesser M. Nishiwaki B. Gammon D. Langohr E. Lalone J. Johnson G. King

Distal radius fractures are the most common fracture of the upper extremity. Malunion of the distal radius is a common clinical problem after these injuries and frequently leads to pain, stiffness loss of strength and functional impairments. Currently, there is no consensus as to whether not the mal-aligned distal radius has an effect on carpal kinematics of the wrist. The purpose of this study was to examine the effect of dorsal angulation (DA) of the distal radius on midcarpal and radiocarpal joint kinematics, and their contributions to total wrist motion.

A passive wrist motion simulator was used to test six fresh-frozen cadaveric upper extremities (age: 67 ± 17yrs). The specimens were amputated at mid humerus, leaving all wrist flexor and extensor tendons and ligamentous structures intact. Tone loads were applied to the wrist flexor and extensor tendons by pneumatic actuators via stainless steel cables. A previously developed distal radius implant was used to simulate native alignment and three DA deformity scenarios (DA 10 deg, 20 deg, and 30 deg). Specimens were rigidly mounted into the simulator with the elbow at 90 degrees of flexion, and guided through a full range of flexion and extension passive motion trials (∼5deg/sec). Carpal motion was captured using optical tracking; radiolunate and capitolunate joint motion was measured and evaluated.

For the normally aligned radius, radiolunate joint motion predominated in flexion, contributing on average 65.4% (±3.4). While the capitolunate joint motion predominated in extension, contributing on 63.8% (±14.0). Increasing DA resulted in significant alterations in radiolunate and capitolunate joint kinematics (p<0.001). There was a reduction of contribution from the capitolunate joint to total wrist motion throughout flexion-extension, significant from 5 degrees of wrist extension to full extension (p = 0.024). Conversely, the radiolunate joint increased its contribution to motion with increasing DA; significant from 5 degrees of wrist extension to full extension as the radiolunate and capitolunate joint kinematics mirrored each other. A DA of 30 degrees resulted in an average radiolunate contribution of 72.6% ± 7.7, across the range of motion of 40 degrees of flexion to 25 degrees of extension.

The results of our study for the radius in a normal anatomic alignment are consistent with prior investigators, showing the radiocarpal joint dominated flexion, and the midcarpal joint dominated extension; with an average 60/40 division in contributions for the radiocarpal in flexion and the midcarpal in extension, respectfully. As DA increased, the radiocarpal joint provided a larger contribution of motion throughout flexion and extension. This alteration in carpal kinematics with increased distal radius dorsal angulation may increase localised stresses and perhaps lead to accelerated joint wear and wrist pain in patients with malunited distal radial fractures.


E. Lalone B. Gammon R. Willing M. Nishiwaki J. Johnson G. King

Altered distal radioulnar joint contact (DRUJ) mechanics are thought to cause degenerative changes in the joint following injury. Much of the current research examining DRUJ arthrokinematics focuses on the effect of joint malalignment and resultant degenerative changes. Little is known regarding native cartilage contact mechanics in the distal radioulnar joint. Moreover, current techniques used to measure joint contact rely on invasive procedures and are limited to statically loaded positions. The purpose of this study was to examine native distal radioulnar joint contact mechanics during simulated active and passive forearm rotation using a non-invasive imaging approach.

Testing was performed using 8 fresh frozen cadaveric specimens (6 men: 2 women, mean age 62 years) with no CT evidence of osteoarthritis. The specimens were thawed and surgically prepared for biomechanical testing by isolating the tendons of relevant muscles involved in forearm rotation. The humerus was then rigidly secured to a wrist simulator allowing for simulated active and passive forearm rotation. Three-dimensional (3D) cartilage surface reconstructions of the distal radius and ulna were created using volumetric data acquired from computed tomography after joint disarticulation. Using optically tracked motion data and 3D surface reconstructions, the relative position of the cartilage models was rendered and used to measure DRUJ cartilage contact mechanics.

The results of this study indicate that contact area was maximal in the DRUJ at 10 degrees of supination (p=0.002). There was more contact area in supination than pronation for both active (p=0.005) and passive (p=0.027) forearm rotation. There was no statistically significant difference in the size of the DRUJ contact patch when comparing analogous rotation angles for simulated active and passive forearm motion (p=0.55). The contact centroid moved 10.5±2.6 mm volar along the volar-dorsal axis during simulated active supination. Along the proximal-distal axis, the contact centroid moved 5.7±2.4 mm proximal during simulated active supination.

Using the technique employed in this study, it was possible to non-invasively examine joint cartilage contact mechanics of the distal radioulnar joint while undergoing simulated, continuous active and passive forearm rotation. Overall, there were higher contact area values in supination compared with pronation, with a peak at 10 degrees of supination. The contact centroid moved volarly and proximally with supination. There was no difference in the measured cartilage contact area when comparing active and passive forearm rotation. This study gives new insight into the changes in contact patterns at the native distal radioulnar joint during simulated forearm rotation, and has implications for increasing our understanding of altered joint contact mechanics in the setting of deformity.


E.A. Lalone R. Grewal G. King J. MacDermid

Long term outcomes of distal radius fractures have rarely been studied prospectively and do not traditionally extend past 1–2 years following treatment. The purpose of this study was to describe the long term patient-rated pain and disability of patients after a distal radius fracture and to also determine the differences in patient reported pain and disability after one year following injury and at the long term follow-up.

Patients who had previously participated in a prospective study, where baseline and standardised one year follow-up were performed following a distal radius fracture were contact to participate in this long term follow-up (LTFU) study. Eligible cases that consented agreed to evaluation which included being sent a package in the mail contain a letter of information and questionnaire. Baseline demographic data including age and sex, as well as date of fracture, mechanism of fall and attending physician information was obtained for all participating subjects. Patient rated pain and disability was measured at baseline, one year and at long-term follow-up using the Patient Rated Wrist Evaluation (PRWE). Patients were categorised as having had a worse outcome (compared to one year follow-up PRWE scores) if their LTFU PRWE score increased by 5 points, having no change in status (if their score changed by four or less points) or improved if their LTFU PRWE score decreased by 5 or more points.

Sixty-five patients (17 male, 48 female) with an average age of 57 years at the time of injury and 67 years at follow-up were included in the study. The mean length of follow-up was 10.7 (± 5.8) years (range: 3–19 years). Overall, 85% of patients reported having no change or had less patient-reported pain and disability (PRWE) at their long-term follow-up compared to their one year PRWE scores. As well, one year PRWE scores were found to be predictive (20.2%) of the variability in long term PRWE score (p=0.001).

This study provided data on a cohort of prospectively followed patients with a distal radius fracture, approximately 10 years after injury. This data may be useful to clinicians and therapists who are interested in determining the long term effects of this frequently occurring upper extremity fracture. The results of this study indicate that after 10 years following a distal radius fracture, 85% of patients will have good outcomes. The results of this study also indicate that majority of cases, if patients have a low amount of pain and disability at one year, then these outcomes will also be true approximately 10 years later.


M. Hupin M. Okada P. Daneshvar

Supercharged end-to-side nerve transfer for severe cubital tunnel syndrome is a recently developed technique which involves augmenting the ulnar motor branch with anterior interosseous nerve (AIN). Previous studies suggested that this technique augments or “babysits” the motor end plates until reinnervation occurs, however, some authors suggested possible reinnervation by the donor nerve. We present two cases where this transfer was done for rapid progressive (6–9 months) cubital tunnel syndrome.

The first case was a 57 year-old right hand dominant female who presented to us with severe right cubital tunnel syndrome clinically, including intrinsic wasting and claw deformity. The patient had significant loss of function and visible atrophy to her hand intrinsics over the last few months. Electrodiagnostic studies confirmed the diagnosis of severe cubital tunnel syndrome demonstrating axonal loss, positive sharp waves and fibrillations in the ulnar nerve distribution distally. The patient underwent cubital tunnel ulnar nerve release, subcutaneous anterior transposition, Guyon's canal release along with an AIN to ulnar motor nerve end-to-side transfer. Patient-based functional outcome instruments were prospectively collected with improved overall pain and function as demonstrated from a quickDASH score of 9.1 1 year post-op in comparison to a score of 34.1 pre-op. Recovery was monitored clinically and electrodiagnostic studies at 6 months and 1 year post-operatively. She demonstrated improved intrinsic muscle bulk and strength. The nerve studies at one year showed reinnervation with large amplitude motor unit potentials in the 1st dorsal interosseous and abductor digiti minimi but the 5th finger sensory response remained absent. The second case was a 58 year-old right hand dominant male diagnosed with severe and progressive right cubital tunnel syndrome. Clinically, he had significant muscle wasting and weakness and confirmed denervation on electrodiagnostic studies. He underwent the same surgical procedure as described for the first case and follow-up regimen. The patient demonstrated improved pain score and significant overall function recovery with a quickDASH score of 11.4 one year post-op in comparison to 72.7 pre-op. Nerve studies at one year confirmed our clinical impression, showing ulnar nerve reinnervation with large amplitude motor unit potentials in the 1st dorsal interosseous, while sensory response remained absent.

It is yet unclear if end-to-side nerve transfers allow reinnervation of the target muscles. Previous studies have demonstrated clinical improvement with this transfer, however we are unaware of any electrodiagnostic studies demonstrating this effect. These two cases support the notion of reinnervation after an end-to-side procedure. Further studies are needed to assess outcomes of such nerve transfers.


M. Abou-Ghaida G. Johnston S.A. Stewart

Displaced distal radial fractures in adults are commonplace. Acknowledging that satisfactory radiographic parameters typically will beget satisfactory functional outcomes, management of these fractures includes a reduction followed by either cast/splint immobilisation or internal fixation. While we can generally rely on internal fixation to maintain the reduction the same is not true of cast immobilisation. There are, however, limited data defining the fate of a fracture reduction in those treated in a cast and up to the time of radial union. Traditional practice is to recommend six weeks of immobilisation. Our goal was to detail the radiographic patterns of change in the radiographic parameters of radial inclination (RI), ulnar variance (UV) and radial tilt (RT) over the first twelve weeks in women fifty years old and older who had sustained a displaced distal radial fracture.

We examined serial standard PA and lateral distal radius radiographs of 647 women treated by closed reduction and casting for a displaced fracture of the distal radius. Measurements of RI, UV and RT from standardised radiographs were made immediately post-reduction as well as, as often as possible/feasible, at 1,2,3,6,9 and 12 weeks post fracture. All measurements were made by the senior author (accuracy range: 2 degrees for RI, 1 mm for UV and 4 degrees for RT, in 75% of cases). The primary outcome measure was the change in fracture position over time. Secondary outcomes included changes related to age group; known bone density; the relation to associated ulnar fractures; and independence of the variables of RI, UV and RT.

The mean immediate post-reduction values for RI, UV and RT were 21 degrees, 1.5 mm, and −6 degrees, respectively. These all changed in the first six weeks, and did not in the second six week period. The mean change in RI was 3 degrees, 60% of the change occurring in the first week post-reduction; only 0.3 degrees of change was noted beyond three weeks. The mean UV increased by 2.2 mm over the first 6 weeks, 23% in the first week post reduction. The mean RT change of 7.7 degrees was also gradual over the first 6 weeks, with no significant change afterwards. The RI changes identified were not influenced by patient age, while UV and RT changes were greater in older groups. Those fractures of the distal radius associated with a distal ulnar shaft or neck fracture did not lose radial inclination over the study period.

We have defined patterns of loss of reduction that commonly occur post reduction of a displaced distal radius fracture in women fifty years and older. Such patterns ought to guide our closed management of distal radial fractures, whether by altering the duration or method of casting. Women fifty years old and older, and physicians alike, must be advised that conventional casting post distal radial fracture reduction unreliably maintains fracture reduction.


A. Senay M. Benderdour G.Y. Laflamme P. Ranger Q. Shi J. Delisle J. Fernandes

Total joint arthroplasty has proven to be efficient to relieve pain and regain mobility. In fact, most patients undergoing a total knee arthroplasty (TKA) are satisfied with their surgery (80 to 90%), yet 4 to 7% still complain of unexplainable pain and stiffness. Several authors have proposed that reactivity to the implant could explain this phenomenon. Still, no strong evidence supports this theory as of today. We aimed to determine the prevalence of metal and cement hypersensitivity in a cohort of patients with unexplained pain and stiffness after TKA.

We retrieved data for a group of patients presenting unexplained pain and stiffness. We excluded all other potential known causes of pain. All patients were tested with a Lymphocyte Transformation Test from whole blood taps. We analysed data of hypersensitivity to metals (alloy particles of titanium and cobalt, aluminum, cobalt, nickel, zirconium, vanadium, molybdenum, cobalt, chromium and iron) and PMMA cement (bone cement monomer and particles).

Fifty-three patients underwent a LTT for unexplained pain and stiffness after total knee arthroplasty between May 2012 and May 2015. The cohort consisted of 26 men and 27 women with a mean age of 66.3(±8.0) years. Six patients had no hypersensitivity (11.3%), leaving 88.7% of the cohort with hypersensitivity to metal and/or cement. Almost half the cohort of patients tested for PMMA was hypersensitive to cement (44.0%). The most common metal hypersensitivity was nickel (69.8%). Twelve patients presented sensitivity to only one metal (22.6%), whereas 35 patients were hypersensitive to more than one metal (66.0%). Eleven patients had revision surgery with a hypoallergenic prosthesis. Patients reported a significant diminution of pain as well as better knee function compared to preoperative status as early as 6 weeks postop, although some reported residual stiffness.

The results of this study suggest that metal and/or cement hypersensitivity could play a role in cases of total knee arthroplasty with unexplained pain and stiffness. Randomised controlled clinical trials on the subject will be initiated by our team to further investigate this phenomenon.


D. Yin J. Jun J. Delisle A. Banica A. Senay G.Y. Laflamme P. Ranger J.C. Fernandes

Blood loss is a major concern in total knee arthroplasty (TKA) along with postoperative knee function. The present study explores the impact of tourniquet and closed-suction drains on blood loss as well as knee function in TKA.

A prospective clinical trial was conducted on 111 patients admitted for TKA. Subjects were divided into three groups based on duration of tourniquet use (T+: whole-course tourniquet, T-: cementation only tourniquet) and usage of closed-suction drain (D+: drain use, D-: no drain). Thirty-six subjects were included in group T+D+, 42 in T-D+ and 33 in T-D-. Data from study population was analysed for pre and post-operative hemoglobin level (Hb), perioperative and total blood loss, blood transfusion rates, knee range of motion (ROM), and pain level assessment. Direct and indirect costs associated to nursing time and drains were calculated. Results are presented in mean ± SD.

No statistically significant differences were observed among the three groups (T+D+, T-D+ and T-D-) concerning total blood lost (calculated using Gross' formula), Hb levels over the first six postoperative weeks, blood transfusion rates and intra-articular hematomas. Intraoperative bleeding was significantly reduced in T+ subjects compared to T- subjects (100 ± 88 mL vs. 279 ± 235 mL respectively, p < 0.001), yet length of surgery was unaffected by the different tourniquet inflation strategies. Hidden blood loss was lower in D+ subjects compared to D- subjects (1161 ± 554 mL vs. 1667 ± 554 mL respectively, p < 0.001), but it was compensated by the blood loss in the drains. Early post operative ROM (flexion: 79.1 ± 14.8°, extension: −5.0 ± 6.7°) was superior in group T-D- compared to group T+D+ (flexion: 71.9 ± 17.1°, p = 0.071°; extension: −9.9 ± 6.4°, p = 0.004). Nevertheless, ROM six weeks postoperative was not statistically different between groups (flexion: 114.0 ± 13.3°, extension: 0.4 ± 5.2°). Patient-reported postoperative pain was also similar in all groups. Nursing time dedicated to drain management was 30 min/patient (330h total for 660 patients/year). Total costs related to drains were $31.92CAD/patient ($21,067CAD total for 660 patients/year).

Our results suggest that whole-course tourniquet and closed-suction drain use in TKA do not yield beneficial results in total blood loss, blood transfusion rates, complication rates and knee rehabilitation. Their clinical relevance in TKA is questionable. Moreover, nursing time and costs related to drains should have been allocated elsewhere in patient care.


B. Lanting J. Thoren X. Yuan R. McCalden J. McAuley S. MacDonald E. Vasarhelyi J. Howard D. Naudie M. Teeter

Adequate fixation of implant components is an important goal for all arthroplasty procedures. Aseptic loosening is one of the leading causes of revision surgery in total knee arthroplasty. Radiostereometric analysis (RSA) is an imaging technique to measure implant migration, with established migration thresholds for well-fixed, at risk, and unacceptably migrating components. The purpose of the present study was to examine the long-term fixation of a cemented titanium fixed bearing polished tibial baseplate.

Patients enrolled in a previous two-year prospective trial were recalled at ten years. All patients received a cemented, posterior-stabilised total knee replacement of the same design implanted by one of three surgeons. Of the original 35 patients, 16 were available for long-term follow-up, with one patient lost to follow-up, nine patients deceased, and a further nine patients unwilling to return to the clinic. Each patient underwent RSA imaging in a supine position using a conventional RSA protocol. Migration of the tibial component in all planes as well as maximum total point motion (MTPM) was compared between all time points (baseline, six weeks, three months, six months, one year, two years) up to the ten year follow-up visits. Outcome scores including the Knee Society Score (KSS), WOMAC, SF-12, and UCLA Activity Score were recorded.

At ten years, the mean migrations of the tibial component were less than 0.1 mm and 0.1 degree in all planes relative to the post-operative RSA exam. There was no significant difference in tibial component migration between time points. However, MTPM increased significantly over time (p = 0.002), from 0.23 ± 0.18 mm at six weeks to 0.42 ± 0.20 mm at ten years. At one year, 13 patients had an acceptable MTPM level, three patients had an ‘at risk’ level, and no patient had an ‘unacceptable’ level. No patients were revised at ten years. WOMAC and KSS were significantly improved (p < 0.0001) at the latest follow-up compared to pre-operatively, but there was no difference in SF-12. The median UCLA Activity Score at latest follow-up was six (range, two to eight).

The tibial baseplate demonstrated solid fixation at ten years. No patients had an unacceptable MTPM level at one year and no patients were revised at ten years, supporting the use of RSA to predict long-term loosening risk. The low level of tibial baseplate migration found in the present study correlates to the low rate of revision for this implant as reported in individual studies and in joint replacement registries.


H.S. Dhotar F. Guirguis D. Backstein

Recent analyses of failure mechanisms continue to show aseptic loosening as the predominant mechanism of total knee arthroplasty (TKA) failure. Evaluation for aseptic loosening begins with careful assessment of plain films radiographs, however the utility of examining lucent lines under a cemented tibial tray remains unclear. The purpose of this study is to examine the distribution of lucent lines under cemented tibial components on single-series anteroposterior (AP) and lateral plain radiographs and to determine their significance in the prediction of aseptic loosening found during revision TKA surgery.

Retrospective chart and radiographic review of all patients that underwent revision TKA between 2001–2014 at a single academic hospital center. Revision TKA for periprosthetic fracture, stem fracture, implant dissociation and periprosthetic joint infection were excluded. The most recent pre-revision surgery AP and lateral knee radiographs were assessed by two fellowship trained adult reconstruction surgeons blinded to patient demographics and intraoperative details. Lucent lines under the tibia tray defined as >2mm were documented according to the new KSS radiographic scoring system. Demographic details and the surgeon's assessment whether the tibia tray was loose intraoperatively were extracted from chart review and the operative note, respectively. Univariate and multivariable logistic regression modeling was used to predict the outcome of aseptic loosening.

Between 2001 and 2014, 312 revision TKAs were performed that met our inclusion criteria. Of these, 84 (26.9%) had intraoperative loose tibia trays. We observed a significantly increased risk of aseptic tibia loosening among older patients at time of surgery (odds ratio [OR] 1.05, 95% CI 1.02, 1.08). Posterior stabilised primary TKA components conferred a significantly decreased risk of aseptic tibia loosening (OR 0.36, 95% 0.21, 0.60). On an AP radiograph, after adjustment for other zones, the presence of a lucent line in zone 1, 2 or 3 were all significantly associated with tibia loosening, OR 7.35, 8.69 and 22.26 (p<0.0001) respectively. On a lateral radiograph, after adjustment for other zones, the presence of a lucent line in zone 1, 2 or 3 were all significantly associated with tibia loosening, OR 12.89, 18.03, and 11.63 (p<0.004) respectively. The complete absence of lucent lines under a tibia tray on an AP or lateral radiograph were associated with 96% (CI 0.02, 0.07) and 95% (CI 0.02, 0.09) reduced odds of aseptic tibia loosening.

Careful examination of lucent lines under a tibia component can be highly predictive of aseptic loosening. The areas associated with highest risk of tibia loosening occur in zone 3 on the AP radiograph (medial or lateral to the keel) and zone 2 on the lateral radiograph (posteriorly). The risk of loosening in the absence of lucent line findings on plain films is significantly low.


E. Laende M. Dunbar G. Richardson G. Reardon D. Amirault

The trabecular metal Monoblock TKR is comprised of a porous tantalum base plate with the polyethylene liner embedded directly in the porous metal. An alternative design, the trabecular metal Modular TKR, allows polyethylene liner insertion into the locking base plate after base plate implantation, but removes the low modulus of elasticity that was inherent in the Monoblock design. The purpose of this study was to compare the fixation of the Monoblock and Modular trabeucular metal base plates in a randomised controlled trial.

Fifty subjects (30 female) were randomly assigned to receive the uncemented trabecular metal Monoblock or uncemented trabecular metal Modular knee replacement. A standard procedure of tantalum marker insertion in the proximal tibial and polyethylene liner was followed with uniplanar radiostereometric analysis (RSA) examinations immediately post-operatively and at 6 week, 3 month, 6 month, and 12 month follow-ups. The study was approved by the Research Ethics Board and all subjects signed an Informed Consent Form.

Twenty-one subjects received Monoblock components and 20 received Modular components. An intra-operative decision to use cemented implants occurred in 5 cases and 4 subjects did not proceed to surgery after enrollment. The clinical precision of implant migration measured as maximum total point motion (MTPM) was 0.13 mm (upper limit of 95% confidence interval of double exams). Implant migration at 12 months was 0.88 ± 0.64 mm (mean and standard deviation; range 0.21 – 2.84 mm) for the Monoblock group and 1.60 ± 1.51 mm (mean and standard deviation; range 0.27 – 6.23 mm) for the Modular group. Group differences in 12 month migration approached clinical significance (p = 0.052, Mann Whitney U-test).

High early implant migration is associated with an increased risk for late aseptic loosening. Although not statistically significant, the mean migration for the Modular component group was nearly twice that of the Monoblock, which places it at the 1.6 mm threshold for “unacceptable” early migration (Pijls et al 2012). This finding is concerning in light of the recent recall of a similar trabecular metal modular knee replacement and adds validity to the use of RSA in the introduction of new or modified implant designs.

Reference: Pijls, B.G., et al., Early migration of tibial components is associated with late revision: a systematic review and meta-analysis of 21,000 knee arthroplasties. Acta Orthop, 2012. 83(6): p. 614–24.


E.A. Hassan A. Tucker A. Clouthier K. Deluzio S. Brandon M. Rainbow

Valgus knee unloader braces are often prescribed as treatment for knee osteoarthritis (OA). These braces are designed to redistribute the loading in the knee, thereby reducing medial contact forces. Patient response to bracing is variable; some patients experience improvements in joint loading, pain, and function, others see little to no effect. We hypothesised that patients who experienced beneficial response to the brace, measured by reductions in medial contact force, could be predicted based on static and dynamic measures.

Participants completed a WOMAC questionnaire and walked overground with and without an OA Assist knee brace in a motion capture lab. Eighteen patients with medial compartment OA (8 female, 53.8±7.0 years, BMI 30.3±4.1, median Kellgren-Lawrence grade 4 (range 1–4)) were evaluated. The abduction moment applied by the brace was estimated by multiplying brace deflection by the pre-determined brace stiffness. A generic musculoskeletal model was scaled for each participant based on standing full length radiographs and anatomical markers. Inverse kinematics, inverse dynamics, residual reduction, and muscle analysis were completed in OpenSim 3.2. A static optimisation was then performed to estimate muscle forces and then tibiofemoral contact forces were calculated. Brace effectiveness was defined by the difference in the first peak of the medial contact force between braced and unbraced conditions. Principal component analysis was performed on the hip, knee, and ankle angles and moments from the unbraced walking condition to extract the principal component (PC) scores for these variables. A linear regression procedure was used to determine which variables related to brace effectiveness. Potential regressors included: hip-knee-ankle angle and medial joint space measured radiographically; KL grade; mass; WOMAC scores; unbraced walking speed; and the first two principal component scores for each of the unbraced hip, knee, and ankle joint angles and moments.

KL grade, walking speed, and hip adduction moment PC1, which represented the magnitude of the first peak were all found to be correlated with change in medial contact force. The brace was more successful in reducing medial contact force in subjects with higher KL grades, faster self-selected walking speeds, and larger peak external hip adduction moments. The R2 value for the overall regression model was 0.78.

The best predictor of brace effectiveness was the hip adduction moment, indicating the need to consider dynamic measures. Participants who had hip adduction moments and walking speeds similar to those of their healthy counterparts saw a greater reduction in medial contact force. Thus, those who responded to bracing had more severe OA as measured by the KL grade but had not experienced changes in their hip adduction moment due to OA. The results of this study suggest that there is potential for an objective criterion for valgus knee brace use to be established.


Z. Sisko M. Teeter B. Lanting J. Howard R. McCalden D. Naudie S. MacDonald E. Vasarhelyi

Previous retrieval studies demonstrate increased tibial baseplate roughness leads to higher polyethylene backside wear in total knee arthroplasty (TKA). Micromotion between the polyethylene backside and tibial baseplate is affected by the locking mechanism design and can further increase backside wear. The purpose of this study was to examine modern locking mechanisms, in the setting of both roughened and polished tibial baseplates, on backside tibial polyethylene wear.

Five TKA models were selected, all with different tibial baseplate and/or locking mechanism designs. Six retrieval tibial polyethylenes from each TKA model were matched based on time in vivo (TIV), age at TKA revision, BMI, gender, number of times revised, and revision reason. Two observers scored each polyethylene backside according to a visual damage score and individual damage modes. Primary outcomes were mean damage score and individual damage modes. Demographics were compared by one-way ANOVA. Damage scores and modes were analysed by the Kruskal-Wallis test and Dunn's multiple comparisons test.

There were no differences among the groups based on TIV (p=0.962), age (p=0.651), BMI (p=0.951), gender, revision number, or reason for revision. There was a significant difference across groups for mean total damage score (p=0.029). The polished tibial design with a partial peripheral capture locking mechanism and anterior constraint demonstrated a significantly lower score compared to one of the roughened tibial designs with a complete peripheral-rim locking mechanism (13.0 vs. 22.1, p=0.018). Otherwise, mean total damage scores were not significant between groups. As far as modes of wear, there were identifiable differences among the groups based on abrasions (p=0.005). The polished design with a tongue-in-groove locking mechanism demonstrated a significantly higher score compared to both groups with roughened tibial baseplates (5.83 vs. 0.83, p=0.024 and 5.83 vs. 0.92, p=0.033). Only the two designs with roughened tibial baseplates demonstrated dimpling (5.67 and 8.67) which was significant when compared against all other groups (p0.99). No other significant differences were identified when examining burnishing, cold flow, scratching, or pitting. No polyethylene components exhibited embedded debris or delamination.

Total damage scores were similar between all groups except when comparing one of the polished TKA design to one of the roughened designs. The other TKA model with a roughened tibial baseplate had similar damage scores to the polished designs, likely due to its updated locking mechanism. Dimpling wear patterns were specific for roughened tibial baseplates while abrasive wear patterns were identified in the design with a tongue-in-groove locking mechanism. Our study showed even in the setting of a roughened tibial baseplate, modern locking mechanisms decrease backside wear similar to that of other current generation TKA designs.


M.A. O Al Sobeai L.M. Epure S. Bergeron O. Huk D. Zukor J. Antoniou

Utilising the (ACS-NSQIP) database, we aimed to evaluate the impact of resident level of training on surgical outcome following (TKA) and to compare the US and Canadian health care training system in regards to 30 days postoperative complications and readmission rates.

Using the (CPT) codes we selected from the 2011 and 2012 NSQIP database elective primary TKA with the resident surgeon involved. Of these, all cases with a primary diagnosis code of infection, fracture, mechanical complication, or malignancy and all cases with incomplete or incongruous demographic information were excluded. We also eliminated all the cases with the Attending not present. A total of 2513 cases were included in the study. The cases were stratified into three groups according to the postgraduate level of training {PGY 1 to 3 (junior resident), PGY 4 to 5 (senior resident), and fellow}. Univariate analysis of all patient demographics, comorbidities, intra and postoperative variables, length of surgery, hospital stay and 30 days readmission rates were conducted in order to identify differences between the groups. A standard student's t test was used for continuous variables while the ChiSquared was used for categorical variables. Multivariable logistic regression models were created to assess the independent effect of the resident level of training on the 30 days major complication and re-admission rates while controlling for all other variables.

We identified, 854 (34%) TKAs with junior residents, 1013 (40%) TKAs with senior residents and 646 (26%) TKAs with fellows' participation. Junior residents had a significant (p<0.0001) longer operative time (107±36 minutes) compared with senior residents and fellows. Length of hospital stay was longer in the fellow group probably because of their involvement in more complicated cases. Additionally, an increased number of blood transfusion was observed for the cases performed with involvement of senior residents when compared with the other two groups. However, no significant difference in complications was observed across training levels. When comparing US (2074 TKAs) versus Canada (423 TKAs) cases, we found that fellow contribution to TKA surgeries is higher in Canada. The occurrence of pulmonary embolism and pneumonia was three times higher in Canada cases, while blood transfusion was more frequent in US. Increased operative time, ASA class, age, diabetes, percutaneous cardiac intervention, and steroid use were all independent risk factors for complications following primary TKA. However, no significant difference was observed between the two groups with regards to major complications suggesting no difference between Canadian and American training system in regards to post operative complication.

Our results support previous study study indicating that involvement of residents did not affect the surgical outcome within 30 days when compared to cases with no resident involvement. Our study suggests that resident level does not independently increase the risk of short term complications and support continuing involvement of junior trainees in TKA.


T.C. Gascoyne S.L. Parashin T.R. Turgeon E.R. Bohm E. Laende M. Dunbar

Articulation of the polyethylene (PE) insert between the metal femoral and tibial components in total knee replacements (TKR) results in wear of the insert which can necessitate revision surgery. Continuous PE advancements have improved wear resistance and durability increasing implant longevity. Keeping up with these material advancements, this study utilises model-based radiostereometric analysis (mbRSA) as a tool to measure in vivo short-term linear PE wear to thus predict long-term wear of the insert.

Radiographic data was collected from the QEII Health Sciences Centre in Halifax, NS. Data consisted of follow-up RSA examinations at post-operative, six-, 12-, and 24-month time periods for 72 patients who received a TKR. Implanted in all patients were Stryker Triathlon TKRs with a fixed, conventional PE bearing of either a cruciate retaining or posterior stabilised design. Computer-aided design (CAD) implant models were either provided by the manufacturer or obtained from 3D scanned retrieved implants. Tibial and femoral CAD models were used in mbRSA to capture pose data in the form of Cartesian coordinates at all follow-ups for each patient. Coordinate data was manually entered into a 3D modeling software (Geomagic Studio) to position the implant components in virtual space as presented in the RSA examinations. PE wear was measured over successive follow-ups as the linear change in joint space, defined as the shortest distance between the tibial baseplate and femoral component, independently for medial and lateral sides. A linear best-fit was applied to each patient's wear data; the slope of this line determined the annual wear rate per individual patient. Wear rates were averaged to provide a mean rate of in vivo wear for the Triathlon PE bearing.

Mean linear wear per annum across all 72 patients was 0.088mm/yr (SD: 0.271 mm/yr) for the medial condyle and 0.032 mm/yr (SD: 0.230 mm/yr) for the lateral condyle. Cumulative linear wear at the 2-year follow-up interval was 0.207mm (SD: 0.565mm) and 0.068mm (SD: 0.484mm) for the medial and lateral condyles, respectively.

Linear PE wear measurements using mbRSA and Geomagic Studio resulted in 0.056mm/yr additional wear on the medial condyle than the lateral condyle. Large standard deviations for yearly wear rates and cumulative measurements demonstrate this method does not yet exhibit the accuracy needed to provide short-term in vivo wear measurement. Inter-patient variability from RSA examinations is likely a source of error when dealing with such small units of measure. Further analysis on patient age and body mass index may eliminate some variability in the data to improve accuracy. Despite high standard deviations, the results from this research are in proximity to previously reported linear wear measurements 0.052mm/yr and 0.054mm/yr. Linear wear analysis will continue upon completion of >100 patients, in addition to volumetric PE wear over the entire articulating surface.


N. Matlovich B. Lanting S. MacDonald M. Teeter J. Howard

The concept of constitutional varus and controversy regarding placing the total knee arthroplasty (TKA) in a neutral versus physiologic alignment in varus osteoarthritic (OA) patients is an important current discussion. However, the physiologic mechanical alignment of a varus OA knee is unknown and the relative contribution of the femur and tibia to the mechanical axis is unknown. The goal of this study was to determine and analyse the physiologic mechanical axis of medial OA knees.

Plain radiographs of the knee and full-leg standing radiographs of 1558 patients were reviewed for inclusion criteria; 313 patients with a non-arthritic knee and a contralateral varus end-stage OA knee were analysed in the coronal plane. The Hip-Knee-Ankle (HKA), Condylar-Hip (CH)(femoral), Condylar-Plateau (CP) (intra-articular) and Plateau-Ankle (PA)(tibial) angles were measured for both the arthritic and non-arthritic/physiologic knee. The relationship and contribution of all angles was analysed for every 2° degrees of progressive varus: from 4° valgus to 8° varus. The proportion of patients with constitutional varus was also determined for the sample population and correlated with increasing HKA.

The mean CH (femoral) angle was valgus in all groups and decreased with progressive varus alignment (p< 0.0001), ranging from 3.8° ± 1.0° with HKA of 2–4° valgus, to 0.1° ± 1.5° with HKA of 6–8° varus. The mean PA (tibial) angle was varus in all groups and decreased from valgus to progressively varus alignment (p p<0.0001), ranging from 0.78° ± 1.4° with HKA 2–4° valgus, to 5.6° ± 1.9° with HKA 6–8° varus. The CP angle showed no difference between all groups (p=0.3). Forty five percent of males and 22% of females with arthritic HKA in varus alignment were found to have constitutional varus.

Correlation of unilateral arthritic knees to the unaffected, physiologic aligned knee using full-leg radiographs indicates that it may be possible to understand the patient's physiologic, pre-arthritic coronal plane alignment. The mechanical axis of physiologic knees in a unilateral varus OA population demonstrates a variable contribution of the femur (CH) and tibia (PA) from overall valgus to varus alignment. In addition, a significant proportion of the sample population possessed constitutional varus. This may provide important information regarding the placement of physiologic TKA's and direct future research questions.


J. Mutch A. Cracchiolo P. Keating S.E. Lemos

The absence of menisci in the knee leads to early degenerative changes. Complete radial tears of the meniscus are equivalent to total meniscectomy and repair should be performed if possible. The purpose of this study was to biomechanically compare the cross suture, hashtag and crosstag meniscal repairs using all-inside implants for radial tears.

Radial tears were created at the mid-body of 36 fresh-frozen lateral human menisci and then repaired, in randomiSed order, with Fast-Fix™ 360s (Smith & Nephew, Andover, MA) using the cross suture, hashtag and crosstag techniques. The repaired menisci were tested using an Instron Electropuls E10000 (Instron, Norwood, MA). The tests consisted of cyclic loading from 5 to 30N at 1Hz for 500 cycles, then a load to failure test. Displacement following cyclic loading, load at 3mm of displacement, load to failure, and stiffness were recorded. Any differences between repairs were assessed using Kruskal-Wallis and Mann Whitney tests (p<0.05).

Cross suture repairs displaced more following cyclic loading and resisted less load to failure than both the hashtag and crosstag repairs. However, these differences were not statistically significant. The average displacement following cyclic loading of cross suture, hashtag, and crosstag repairs was 4.34 mm (±2.02 mm), 3.46 mm (±2.12 mm), and 3.24 mm (±1.52 mm) respectively (p=0.33). Maximal load to failure was 64.83 N (±17.41 N), 74.52 N (±9.03 N), and 74.98N (±10.50N), respectively (p=0.419).

All-inside cross suture, hashtag and crosstag repairs all displaced >3mm with cyclic loading, which is the threshold for meniscal insufficiency. This contrasts previous studies using inside-out sutures, where crosstag and hashtag repairs resisted cyclic loading (< 3mm). Inside-out suturing for radial tears of the lateral meniscus currently remains the gold standard.


G. Corbo T. Lording T. Burkhart A. Getgood

Injury to the anterolateral ligament (ALL) has been reported to contribute to high-grade anterolateral laxity following anterior cruciate ligament (ACL) injury. Failure to address ALL injury has been suggested as a cause of persistent rotational laxity following ACL reconstruction. However, lateral meniscus posterior root (LMPR) tears have also has been shown to cause increased internal rotation and anterior translation of the knee. Due to the anatomic relationship of the ALL and the lateral meniscus, we hypothesise that the ALL and lateral meniscus work synergistically, and that a tear to the LMPR will have the same effect on anterolateral laxity as an ALL tear in the ACL deficient knee.

Sixteen fresh frozen cadaveric knee specimens were potted into a hip simulator(femur) and a six degree-of-freedom load cell (tibia). Two rigid optical trackers were inserted into the proximal femur and distal tibia, allowing for the motion of the tibia with respect to the femur to be tracked during biomechanical tests. A series of points on the femur and tibia were digitised to create bone coordinate systems that were used to calculate the kinematic variables. Biomechanical testing involved applying a 5Nm internal rotation moment to the tibia while the knee was in full extension and tested sequentially in the following three conditions: i) ACLintact; ii) Partial ACL injury (ACLam) – anteromedial bundle sectioned; iii) Full ACL injury (ACLfull). The specimens were then randomised to either have the ALL sectioned first (ALLsec) followed by the LMPRsec or vice versa. Internal rotation and anterior translation of the tibia with respect to the femur were calculated. A mixed two-way (serial sectioning by ALL section order) repeated measures ANOVA (alpha = 0.05).

Compared to the ACLintact condition, internal rotation was found to be 1.78° (p=0.06), 3.74° (p=0.001), and 3.84° (p=0.001) greater following ACLfull, LMPRsec and ALLsec respectively. LMPRsec and the ALLsec resulted in approximately 20 of additional internal rotation (p=0.004 and p=0.01, respectively) compared with the ACL deficient knee (ACLfull). No difference was observed between the ALL and LMPR sectioned states, or whether the ALL was sectioned before or after the LMPR (p=0.160). A trend of increasing anterior translation was observed when the 5Nm internal rotation moment was applied up until the ACL was fully sectioned; however, these differences were not significant (p=0.070).

The ALL and LMPR seem to have a synergistic relationship in aiding the ACL in controlling anterolateral rotational laxity. High-grade anterolateral laxity following ACL injury may be attributed to injuries of the ALL and/or the LMPR. We suggest that the lateral meniscus should be thought of as part of the anterolateral capsulomeniscal complex (i.e., LM, ITB, and ALL) that acts as a stabiliser of anterolateral rotation in conjunction with the ACL.


S. Kerslake M.R. Lafave L.A. Hiemstra

Clinical management of patellofemoral (PF) instability is a challenge, particularly considering the wide range of contributing variables that must be taken into consideration when determining optimal treatment. An important outcome measure to consider in this patient population is disease-specific quality of life (QOL). The purpose of this study was to factor analyse and reduce the total number of items in the Banff Patellar Instability Instrument (BPII). Subsequent to the factor analysis, the new, item-reduced BPII 2.0 was tested for validity, reliability and responsiveness.

Disease-specific QOL was measured in patients with a confirmed diagnosis of PF instability (n = 223) at the initial consultation with the original BPII. Data from these BPII scores was used to employ a principal component analysis (PCA) to factor analyse and reduce the total number of items in the original BPII, to create the new BPII 2.0. The BPII 2.0 underwent content validation (Cronbach's Alpha, patient interviews and reading-level); construct validation (ANOVA comparing the initial consultation, 6, 12 and 24 month post-operative, Eta squared); convergent validation (Pearson r correlation to the original BPII); responsiveness testing (Eta squared, anchor-based distribution testing); and reliability testing (intra-class correlation coefficient (ICC) 2,k).

The original BPII was successfully reduced from 32 to 23 items. The new BPII 2.0 demonstrated excellent Cronbach's Alpha values: initial consult = 0.91; 6-months = 0.96; 12-months = 0.97; and 24-months post-operative = 0.76. Grade-level reading assessment for all items in the BPII 2.0 was below grade twelve. The ANOVA determined the BPII 2.0 was able to discriminate between the initial consultation, 6, 12 and 24 months post-operative assessments, with significant differences between each time-point (p < 0.05). Eta squared was 0.40, demonstrating a medium to large effect size. Convergent validity was established with the BPII 2.0 significantly correlated to the original BPII (initial consult = 0.82, 6-month = 0.90, 12-month = 0.90, and 24-month = 0.94). Anchor-based responsiveness was established with a significant correlation between the 7-point scale of patient-perceived improvement and 24-month post-operative BPII 2.0 scores. Strong reliability was established with an ICC (2,k) = .97.

The BPII has undergone a critical step in its psychometric and clinimetric evolution: structural validation. With the work completed in this study, the BPII and BPII 2.0 have completed assessment of seven of the nine Consensus-based Standards for the selection of health Measurement INstruments (COSMIN) properties including: 1) Internal consistency; 2) Reliability; 3) Standard error of measurement; 4) Content validation; 5) Structural validity; 6) Criterion validity; and, 7) Responsiveness testing. Completion of these assessments and the introduction of a structurally valid and shorter questionnaire, the BPII 2.0, provides a definitive level of credibility to this disease-specific outcome measure.


L.A. Hiemstra S. Kerslake M.R. Lafave

Patellofemoral instability is common injury and proximal soft tissue stabilisation via MPFL reconstruction or imbrication is the mainstay of treatment. The contribution of certain pathoanatomies to the failure of patellofemoral stabilisation is unknown. The purpose of this study was to analyse the failure rate of patellar stabilisation procedures in a large cohort as measured by re-dislocation of the patella. A secondary purpose was to identify the pathoantomical features that may have predisposed these patients to failure.

Between May 2008 and March 2014, 207 MPFL reconstructions and 70 MPFL imbrications were performed by a single surgeon. Post-operative assessment included clinical examination to assess the integrity of the MPFL graft, plain radiographs and the Banff Patellofemoral Instability Instrument (BPII), a disease-specific outcome measure. Failures were identified and risk factors including trochlear dysplasia, patella alta, generalised ligamentous laxity (GLL), femoral tunnel position and rotational abnormalities were evaluated as contributing factors.

There were 48 male and 178 female patients. The mean duration of follow-up was 24.1 months (SD 9.4, range 12–74). The average age at time of surgery was 24.81 years (SD 8.87, range 50.35–8.99). The average BMI was 23.75 (SD 3.62, range 36.70–14.90). There were 10 failures in the MPFL reconstruction group (4.8%), 1 male and 9 females. Femoral tunnel position was assessed in relation to Schottle's point as good or excellent in all 10 cases. In terms of pathoanotomy, 8/10 failures had high-grade trochlear dysplasia, 1/10 had patella alta, 6/10 had a Beighton score of >/= 4, and 3/10 had clinically significant rotational abnormalities of the lower extremity. The primary cause attributed to the 10 failure cases was trauma in two, trochlear dysplasia in three, rotational abnormalities in one, combined femoral anteversion and GLL in two, and combined trochlear dysplasia and GLL in two. There were 13 failures in the MPFL imbrication group (18.6%), 2 males and 11 females. Among these failures, 4/13 had high-grade trochlear dysplasia, 3/13 had patella alta, 10/13 had a Beighton score of >/= 4, and one had clinically significant rotational abnormalities of the lower extremity. The primary pathology that was considered to contribute to the imbrication failure cases was trochlear dysplasia in four, generalised ligamentous laxity in six, rotational abnormalities in one, patella alta with trochlear dysplasia in one, and generalised ligamentous laxity with trochlear dysplasia in one. Prior to surgical failure the mean BPII score for the failure group was 71.5/100, compared with 74.6/100 for the remainder of the cohort.

MPFL reconstruction is highly successful surgical procedure for stabilising the unstable patella with a failure rate of only 4.8%. Higher failure rates are seen in patients undergoing imbrication of the MPFL compared to a reconstruction. Pathoanatomies that contribute to failure vary between patients with the most common being trochlear dysplasia and generalised ligamentous laxity.


R.A. Schachar S.M.A. Heard L.A. Hiemstra G.ML. Buchko M.R. Lafave S. Kerslake

The aim of an anterior cruciate ligament (ACL) reconstruction is to regain functional stability of the knee following ACL injury, ideally allowing patients to return to their pre-injury level of activity. The purpose of this study was to assess clinical, functional and patient-centered outcomes a minimum of 1-year following ACL reconstruction. This study assessed for relationships between post-operative ACL graft laxity, functional testing performance, and scores on the ACL Quality of Life (ACL-QOL) questionnaire.

A prospective cohort study design (n = 1938) was used to gather data on clinical laxity, functional performance and quality of life outcomes. Post-operative ACL laxity assessment using the Lachman and Pivot-shift tests was completed independently on each patient by a physiotherapist and an orthopaedic surgeon at a minimum of 12-months post-operatively. A battery of functional tests was performed including single leg balance, single leg landing, 4 single-leg hop tests, and tuck jumps. The hop tests provided a comparative assessment of limb-to-limb function including a single hop for distance, a 6m timed hop, a triple hop for distance, and a triple crossover hop. Patients com¬pleted the ACL-QOL at the 12-month and 24-month post-operative appointments. Descriptive and demographic data were collected for all patients. The degree and frequency of post-operative laxity was calculated. A Pearson r correlation coefficient was employed to determine the relationship between the presence of post-operative laxity and the ACL-QOL scores, between the battery of functional tests and the ACL-QOL scores, as well as between the functional tests and the laxity assessments.

Data was gathered for 1512/1938 patients (78%). At clinical assessment a minimum of 1-year post-operatively, 13.2% of patients demonstrated a positive Lachman and/or Pivot-shift test. The mean ACL-QOL score for patients with no ACL laxity was 80.8/100, for patients with a positive Lachman or Pivot-shift test the mean score was 72.3/100, and for patients with both positive Lachman and Pivot-shift tests the score was 66.9/100. Pearson r correlation coefficient demonstrated a significant relationship between the presence of ACL graft laxity and ACL-QOL score (p < 0.05). Statistically significant correlations were evident between all of the operative limb single-leg hop tests and the post-operative ACL-QOL scores (p < 0.05). Statistically significant correlations were evident between the operative limb triple-hop tests and presence of ACL graft laxity (p < 0.05).

Patients with clinically measurable ACL graft laxity demonstrate lower ACL-QOL scores as well as lower performance on a battery of functional tests. The disease-specific outcome measure was strongly correlated to the patient's ability to perform single-limb functional tests, indicating that the ACL-QOL score accurately predicted level of function.


D. Nguyen

Background The minimum size required for a successful quadrupled hamstring autograft ACL reconstruction remains controversial. The risks of ACL re-tear in younger patients who tend to participate in a higher level of sports activity, and female athletes who have numerous predisposing factors, are poorly defined. Purpose To identify risk factors for graft re-tears within 2 years of ACL surgery. The hypotheses are that female sex, a smaller size graft, and younger patients will increase the odds of failure. Study Design Cohort Study. Level of evidence, 3.

A cohort of 503 athletes undergoing primary, autograft hamstring ACL reconstruction, performed by a single surgeon using the same surgical technique and rehabilitation protocol, between September-December 2012, was followed for a total duration of 2 years. Return to play was allowed between 6 and 12 months post-surgery upon completion of functional testing. Exclusion criteria included infections, revisions, double bundle techniques, multi-ligament injuries, non-compliance, BTB/allografts/hybrid grafts. Primary outcome consisted of binary data (ACL graft re-tear or no tear) as measured on physical exam (Lachman and pivot shift) and MRI. Multivariate logistic regression statistical analysis with model fitting was used to investigate the predictive value of sex, age, and graft size on ACL re-tear. Secondary sensitivity analyses were performed on the adolescent subgroup, age and graft size as categorical variables, and testing for interactions among variables. Sample size was calculated based on the rule of 10 events per independent variable for logistic regression.

The mean age of the 503 athletes was 27.5 (SD 10.6; range = 12–61). There were 235 females (47%) and 268 males (53%) with a 6 % rate of re-tears (28 patients; 17 females). Mean graft size was 7.9 (SD 0.6; range = 6–10). Univariate analyses of graft size, sex, and age only in the model showed that younger age (odds ratio [OR] = 0.86; 95% confidence interval [CI] = 0.80–0.93; P = .001] and smaller graft size (OR = 0.36; 95% CI = 0.18–0.70; P = .003) were significantly predictive of re-tear. Female sex was correlated with re-tear but was not significant (OR = 1.8; 95% CI = 0.84–3.97; P = .13). Multivariate analysis with all 3 variables in the model showed similar significant results. Graft size < 8 mm (OR = 2.95; 95% CI = 1.33–6.53; P = .008) and age < 25 (OR = 7.01; 95% CI = 2.40–20.53; P = .001) were significantly predictive of re-tear. Entire model was statistically significant (Omnibus test P = .001; Hosmer-Lemeshow statistic P = .68; Receiver Operating Curve [ROC] = 0.8).

Surgeons should counsel their patients who are female, younger than 25 and with a graft size less than 8 mm accordingly and consider modifying their surgical or rehabilitation techniques to mitigate these re-tear risks.


M. Kopka A.A. Rahnemani-Azar E.S. Abebe J. Labrum J.J. Irrgang F.H. Fu V. Musahl

Knee laxity following anterior cruciate ligament (ACL) injury is a complex phenomenon influenced by various biomechanical and anatomical factors. The contribution of soft tissue injuries – such as ligaments, menisci, and capsule – has been previously defined, but less is known about the effects of bony morphology. (Tanaka et al, KSSTA 2012) The pivot shift test is frequently employed in the clinical setting to assess the combined rotational and translational laxity of the ACL deficient knee. In order to standardise the maneuver and allow for reproducible interpretation, the quantitative pivot shift test was developed. (Hoshino et al, KSSTA 2013) The aim of this study is to employ the quantitative pivot shift test to determine the effects of bone morphology as determined by magnetic resonance imaging (MRI) on rotatory laxity of the ACL deficient knee.

Fifty-three ACL injured patients scheduled for surgical reconstruction (36 males and 17 females; 26±10 years) were prospectively enrolled in the study. Preoperative magnetic resonance imaging (MRI) scans were reviewed by two blinded observers and the following parameters were measured: medial and lateral tibial slope, tibial plateau width, femoral condyle width, bicondylar width, and notch width. (Musahl et al. KSSTA 2012). Preoperatively and under anaesthesia, a quantitative pivot shift test was performed on each patient by a single experienced examiner. An image analysis technique was used to quantify the lateral compartment translation during the maneuver. Subjects were classified as “high laxity” or “low laxity” based upon the median value of lateral compartment translation. (Hoshino et al. KSSTA 2012) Independent t-tests and univariate logistic regression were used to investigate the relationship between the pivot shift grade and various features of bone morphology. Statistical significance was set at p<0.05.

A high inter-rater reliability was observed in all MRI measurements of bone morphology (ICC=0.72–0.88). The median lateral compartment translation during quantitative pivot shift testing was 2.8mm. Twenty-nine subjects were classified as “low laxity” (2.8mm). The lateral tibial plateau slope was significantly increased in “high laxity” patients (9.3+/−3.4mm versus 6.1+/−3.7mm; p<0.05). No other significant difference in bone morphology was observed between the groups.

This study employed an objective assessment tool – the quantitative pivot shift test – to assess the contribution of various features of bone morphology to rotatory laxity in the ACL deficient knee. Increased lateral tibial plateau slope was shown to be a significant independent predictor of high laxity. These findings could help guide treatment strategies in patients with high grade rotatory laxity. Further research into the role of tibial osteotomies in this sub-group is warranted.


H.A. Alhamzah A. Hart Y. AlSaran M. Burman P. Martineau

Our study is still in progress. The results mentioned in the abstract are preliminary results. The final results will be provided at the time of presentation.

Over the past decade, the widespread availability of high-resolution ultrasonography coupled with advances in regional anaesthesia have popularised peripheral nerve blocks for anterior cruciate ligament reconstructions (ACLRs). The aim of this study is to investigate whether the femoral nerve block (FNB) administered at the time of ACLR has any long-term impact on the quadriceps strength as compared to patients who did not receive a FNB.

This is a retrospective study. Four hundred charts of patients who underwent ACLR at our institution and had subsequent Biodex testing (an isokinetic rehabilitation test that provides objective information about muscle strength deficits and imbalances of the operated leg compared to the non-operated leg) from 2004 to 2015 were reviewed. Patients who had prior ipsilateral knee surgery, multi-ligament knee injury or at extreme ages were excluded from the study. The following baseline patient characteristics was recorded for each reviewed chart: age, sex, medical comorbidities, the date of the injury, date of the surgery, surgery technical notes and associated procedures, the surgeon, the hospital were the patient was operated, the Biodex test date and the Biodex test results. Data extraction assessed any association between the ACLR patients' who received FNB with the results of the Biodex test after completing the rehabilitation protocol. Descriptive statistics were used to compare the type of anaesthesia, mode of pain control and the results of the Biodex tests between patients grouped by the mode of anaesthesia used at the time of surgery (FNB versus no FNB). A multivariate regression model then compared quadriceps strength (inferred by Biodex test results) between groups while controlling for baseline differences between groups.

Fifty five percent of the ACLR patients received FNB compared to 45% that did not receive FNB over the last 11 years of performing ACLRs (2004–2015) at our institute. Fifty percent of the patients that received FNB failed to achieve more than or equal to 80% quadriceps strength (compared to the contralateral non-operated leg) at 6 months on Biodex test. On the other hand, only 20% of the non-FNB group failed to achieve more than or equal to 80% quadriceps strength.

This study lead us to think that ACLR patients that received FNB are significantly weaker in quadriceps strength at 6 months post ACLR in comparison to non-FNB ACLR patients. This finding subsequently might affect the time needed to return to sports and might indicate a considerable clinical consequence of the FNB on ACL-reconstruction patients.


T.V. Smallman K. Shekitka K. Mann A. Race

This study documents the gross and histologic structure of the infrapatellar plica, and fat pad, and adds to an earlier report to the COA. The important new findings are that the femoral attachment of the plica is an enthesis, and that the plica itself is.

This study seeks to demonstrate that the structure of the fat pad (FP) and infrapatellar plica (IPP) is that of an enthesis organ.

Twelve fresh frozen cadaver knees, each with an IPP, were dissected and the gross anatomic features recorded. The IPP and FP were harvested for study. Representative histologic sections were prepared on tissue fixed in 10% neutral buffered formalin, embedded in paraffin, cut at 4 microns on a rotatory microtome. Staining techniques included hematoxylin and eosin, Masson's trichrome, elastic stain and S100. Appropriate decalcification of sections of the femoral insertion of the IPP was performed. All sections were examined by light microscopy at low, medium and high power. IPP types included 8 separate, 1 split, 2 fenestrated, and one vertical septum. The origin of the IPP is a fibrous arc arising from the apex of the notch separate from the margin of the articular cartilage. This attachment site is the instant centreof rotation of the IPP and FP; they are thus not isometric. The central zone of the IPP consists of a mix of connective tissue types.

Representative sections taken of the femoral attachment of the IPP display a transition zone between dense fibrillar collagen of the IPP, then fibrocartilage and cortical bone similar to a ligament attachment site or enthesis. The central plica histology is composed predominantly of dense regular connective tissue with variable clear space between the collagen bundles, and is thus ligamentous. There is abundant elastase staining throughout, as well as crimping of the collagen suggesting capacity for stretch. S100 staining demonstrates nerves around and in the substance of the IPP. The central body shows lobulated collections of mature adipose tissue admixed with loose connective tissue, containing abundant small peripheral nerves and vessels (all showing crimping and redundancy), merging with the dense fibrous tissue of the IPP. The FP is highly innervated, deformable, and fibro-fatty. Its histology shows lobules of fat, separated by connective tissue septa, which merge with the synovial areolar membrane surrounding the FP.

The linked structures, IPP, central body, and FP occupy the anterior compartment, and function as an enthesis organ: the IPP tethers the FP via the central body and together they rotate around the femoral origin of the IPP. They are not isometric, and must stretch and relax with knee motion. The histology correlates with this requirement. The origin of the IPP is an enthesis, a new observation. Elastase staining, redundancy of vessels and nerves, crimping and redundancy of the dense connective tissue all reflect the requirement to deform. The fat pad merges with the central body, both highly innervated space fillers, tethered by the IPP, which is a non-isometric ligament, also containing nerves. The important clinical significance of these structures is that release of the IPP at the origin reuces or eliminates anterior knee pain in most.


S.M. Heard S. Miller R.A. Schachar S. Kerslake

Chondral defects on the patella are a difficult problem in the young active patient and there is no consensus on how to treat these injuries. Fresh osteochondral allografts are a valid option for the treatment of full-thickness osteochondral defects and can be used to restore joint function and reduce pain. The primary purpose of this study was to investigate the clinical and subjective outcomes of a series of patients following fresh osteochondral allograft transplantation for isolated chondral defects of the patella.

A series of 5 patients underwent surgery using an open approach for graft transplantation. A strict protocol for the allograft tissue was followed. Transplant recipients must be aged <60, have a full-thickness, isolated chondral lesion and have failed previous traditional treatments. The fresh allografts are hypothermically stored at 4°C in X-VIVO10 media for up to 30 days to maintain cartilage viability. Pre- and post-operative clinical measures including knee stability, range of motion, and quadriceps girth were completed. Post-operative plain radiographs were completed including weight-bearing AP, lateral and skyline views. Patient-centred outcome measures including the Knee Osteoarthritis Outcome Score (KOOS) and the Knee Society Score (KSS) were gathered a minimum of 1-year post-operative. Descriptive and demographic data were collected for all patients. A paired t-test was employed to determine the difference between the pre-operative and post-operative outcomes.

All patients were female, with a mean age of 27.4 (SD 3.65). Knee ligament stability was similar pre- and post-operatively. Knee ROM assessment of flexion and extension demonstrated a less than 10° increase from pre to post-operative. Quadriceps girth measurements demonstrated a mean change of 0.5 cm from pre- to post-operative for the surgical limb. Post-operative radiographs demonstrated incorporation of the graft in 4/5 cases within 6-months of surgery. One patient developed fragmentation of the graft after 18-months, and one patient had a subsequent trochleoplasty for persistent pain. The mean KOOS domain scores demonstrated significant improvement (p<0.05) as follows: Symptoms pre-op = 28.57, post-op = 55; Pain pre-op 28.89, post-op = 57.22; ADLs pre-op = 48.92, post-op = 66.18; Sports/Recreation pre-op = 6, post-op = 32; and QoL pre-op = 12.5, post-op = 42.5. Mean pre-op surgical versus non-surgical limb KSS scores were 107.4 and 179 respectively. The mean post-op surgical versus non-surgical limb KSS scores were 166 and 200.

Isolated chondral defects of the patella can cause substantial pain, reduced function, and can be challenging to address surgically. This series of 5 cases demonstrated improved function, KOOS and KSS for 4/5 patients. To our knowledge this is a novel biological procedural technique for this problem, which has shown promising results making it a viable treatment option for young active patients with osteochondral defects of the patella.


K.J. Sheehan B. Sobolev P. Guy L. Kuramoto S. Morin J. Sutherland L. Beaupre D. Griesdale M. Dunbar E. Bohm E. Harvey

Hospital type is an indicator for structures and processes of care. The effect of hospital type on hip fracture in-hospital mortality is unknown. We determine whether hip fracture in-hospital mortality differs according to hospital type.

We retrieved records of hip fracture for 167,816 patients aged 65 years and older, who were admitted to a Canadian acute hospital between 2004 and 2012. For each hospital type we measured and compared the cumulative incidence of in-hospital death by in-patient day, accounting for discharge as a competing event.

The cumulative incidence of in-hospital death at in-patient day 30 was lowest for teaching hospital admissions (7.3%) and highest for small community hospital admissions (11.5%). The adjusted odds of in-hospital death were 12% (95% CI 1.06–1.19), 25% (95% CI 1.17–1.34), and 64% (95% CI 1.50–1.79) higher for large, medium, and small community hospital versus teaching hospital admissions. The adjusted odds of nonoperative death were 1.6 times (95% CI 1.42–1.86), and 3.4 times (95% CI 2.96–3.94) higher for medium and small community hospital versus teaching hospital admissions. The adjusted odds of postoperative death were 14% (95% CI 1.07–1.22) and 20% (95% CI 1.10–1.31) higher at large and medium community hospitals versus teaching hospitals. The adjusted odds of postoperative death were largest at small community hospitals but the confidence interval crossed 1 (OR = 1.25, 95% CI 0.92–1.70).

A higher proportion of hip fracture patients die at non-teaching compared to teaching hospitals accounting for length of stay. Higher mortality at small community hospitals may reflect disparities in access to resources and delay to treatment.


H. Messier D. Plante S. Pelet

This paper presents the nutritional status of a geriatric population admitted for hip fracture. Malnutrition is often associated with the advanced age and can be influenced by physical, mental, social and environmental changes. Hip fracture is a major issue and a prior poor nutritional status is associated with higher rates of perioperative complications and prolonged hospital length of stay. Methods: Prospective observational.

Prospective observational cohort study performed in a Level one trauma centreincluding 110 consecutive patients admitted for hip fracture. The main outcome measure was the Mini Nutritional Assessment (MNA), a specific tool validated for geriatric population. This questionnaire was performed at admission by an independent assessor, at the same time as a large set of demographic and functional data. Blood samples were tested for blood count and albuminemia. Two groups were constituted and analysed according to a MNA score > 24 (lower limit for normal nutritional status). Factors explored included physical and mental items. Impact of malnutrition was determined on hospital length of stay (HLS), discharge in an adverse location than prior to admission (DAL), complications and mortality rate.

The rate of patients with malnutrition (or at risk) in this study is 49.1% (54 patients). Patients with a MNA < 24 are older (83.6 yrs ± 6.5 vs 80.2 ± 8.3, p<0,01), have more comorbidities (Charlson 2.5 vs 1.27, p<0,01), a more impaired mental (MMSE <27 74.1% vs 41.1%, p<0,01) or physical status (MIF 105.3 +/− 26.6 vs 121.8 +/− 6.4, p<0,01). Blood samples are not selective to detect malnutrition (p=0,64). Malnutrition is associated with a longer HLS (25.2 days +/− 24.2 vs 14.2 +/− 9.0, p<0,01), a greater DAL (58.9% vs 38.2%, p=0,02) and a higher 6 months mortality rate (16.7% vs 3.6%, p=0,02).

The prevalence of malnutrition in a geriatric population admitted for hip fracture is high. Blood samples at admission have clearly a poor value and a systematic screening with the MNA is mandatory. An early diagnosis will target specific interventions in order to reduce the physical and socio-economic impact of the malnutrition. Future studies should focus on actions in the perioperative stage (fast-track surgery, nutritional protocols, analgesia) and their impact on the socio-economic burden.


M.E. Sellan D. Bryant C. Tieszer M. MacLeod S.R. Papp A.R. Lawendy A. Liew D. Viskontkas C. Coles T.P. Carey W. Gofton A. Trendholm T. Stone R. Leighton D.W. Sanders

The benefit of using a long intramedullary device for the treatment of geriatric intertrochanteric hip fractures is unknown. The InterTAN device (Smith and Nephew, Memphis TN) is offered in either Short (180–200 mm) or Long (260–460 mm) constructs and was designed to provide stable compression across primary intertrochanteric fracture fragments. The objective of our study was to determine whether Short InterTANs are equivalent to Long InterTANs in terms of functional and adverse outcomes for the treatment of geriatric intertrochanteric hip fractures.

108 patients with OTA classification 31A–1 and 31A–2 intertrochanteric hip fractures were included in our study and prospectively followed at one of four Canadian Level-1 Trauma Centres. Our primary outcomes included two validated primary outcome measures: the Functional Independence Measure (FIM), to measure function, and the Timed Up and Go (TUG), to measure motor performance. Secondary outcome measures included blood loss, length of procedure, length of stay and adverse events. A pre-injury FIM was measured by retrospective recall and all postoperative outcomes were assessed on postoperative day 3, at discharge, at 6 weeks, 3 months, 6 months and 12 months postoperatively. Unpaired t-tests and Chi-square tests were used for the comparison of continuous and categorical variables respectively between the Short and Long InterTAN groups. A statistically significant difference was defined as p<0.05.

Our study included 71 Short InterTAN and 37 Long InterTAN patients with 31A–1 and 31A–2 intertrochanteric hip fractures. Age, sex, BMI, side, living status and comorbidities were similar between the two groups. The mean operative time was significantly lower in the Short InterTAN group (61 mins) as compared to the Long InterTAN group (71 mins)(p0.05). There were 5 periprosthetic femur fractures in the short InterTAN group versus 1 in the long InterTAN group. Non-mechanical adverse outcomes such as myocardial infarction, pulmonary embolism, urinary tract infections, pneumonia and death all had similar incidence rates between the two InterTAN groups.

Both the Short and Long InterTAN patient cohorts displayed similar improvements in performance and overall function over the course of a year following intertrochanteric hip fracture fixation. The recorded operative times for Short InterTAN fixation were significantly shorter than those recorded for the Long InterTAN patients. Alternatively, a significantly higher proportion of Short InterTAN patients sustained periprosthetic femur fractures within a year of implantation as compared to the Long InterTAN group.


R. Ng M.T. Shabani-Rad C. MacAdams

Hip fractures are a common cause of morbidity and mortality in the elderly, with approximately 30,000 hip fractures a year in Canada. Many hip fracture patients are prone to heart failure and present anticoagulated with Warfarin for medical comorbidities including atrial fibrillation or previous thromboembolic disease. Reversal of warfarin anticoagulation to an INR < 1.5 preferred for surgery but this often contributes to a delay to hip fracture surgery, which increases patient pain, morbidity, mortality, and length of stay Octaplex is a small-volume prothrombin complex concentrate (PCC) that reverses Warfarin-related anticoagulation in 15–60 minutes. It has been shown to be safe and effective in the management of intracranial and gastrointestinal bleeding in warfarinised patients. It is recommended by Bone and Joint Canada as an option for urgent warfarin reversal in hip fracture patients. However, there has been no published literature on the use of Octaplex or other PCCs in orthopaedic patients. Our objective is to assess the effectiveness of Octaplex for rapid reversal of warfarin anticoagulation in hip fracture patients.

A database review of all patients who received Octaplex was performed. Medical records of all hip fracture patients in Calgary who received Octaplex between December 2009 and February 2015 were reviewed. After application of inclusion and exclusion criteria, 33 patients were identified. A timeline of International Normalised Ratio (INR), Octaplex administration, and hip fracture surgery was recorded. Mortality and complications were assessed at 30 days.

A single dose of Octaplex corrected the INR to < 1.5 in 29 cases (88%). Median time from administration of Octaplex to a measured INR < 1.5 was 1.1 hours. Median time from admission to hip fracture surgery was 22 hours. Mortality at 30 days was 15.2%, mostly from cardiac arrest. A further 12% of patients developed cardiac or thrombotic complications. Multiple medical comorbidities were common including coronary artery disease (55%), congestive heart failure (45%), and chronic pulmonary disease (39%). Patients who received both fresh frozen plasma (FFP) and Octaplex for warfarin reversal had much higher mortality than those who only received Octaplex (40% vs 4.3% mortality at 30 days), but also had more medical comorbidities.

Octaplex is effective at rapidly reversing warfarin anticoagulation and reducing time to surgery, potentially reducing the morbidity and mortality of hip fractures. Administration of both Octaplex and FFP were associated with higher early mortality in this case series. Further research is required to assess the safety of Octaplex, vitamin K, and FFP for reversal of warfarin anticoagulation in this population.


M. Bellemare J. Delisle Y. Troyanov S. Perreault A. Senay A. Banica P. Beaumont M. Giroux A. Jodoin G.Y. Laflamme S. Leduc J.M. MacThiong M. Malo G. Maurais H. Nguyen S. Parent P. Ranger D.M. Rouleau J.C. Fernandes

Treat to target is the use of a physiologic marker as a monitor of effectiveness or compliance to an intervention. A recent example has been the progressive use of CTX-1 (Marker of osteoclastic activity) as a surrogate of bone resorptive activity in osteoporosis treatment. CTX-1 levels were demonstrated to be inversely related to drug efficacy in the suppression of bone resorption. As far as fragility fractures are concerned, no reference value of CTX-1 for any index fracture sites was found in the literature. In order to prevent subsequent fractures, efforts to better manage this chronic disease are to be explored. The main objective of this study was to compare and validate the use of serum CTX-1 to the perceived compliance to treatment.

Five hundred and forty three patients (men and women) 40 years of age or older who had been treated for a fragility fracture were enrolled. The purpose of this study was to correlate the measurement of CTX-1 with the perceived compliance to treatment of patients at the time of fracture and at six, 12 and 18 months after initiation of treatment. Our secondary objectives were to evaluate two different CTX-1 suppression target levels (CTX-1< 0.3 ng/mL and CTX-1<0.2 ng/mL), to determine CTX-1 values according to fracture sites, and to explore the profile of patients with subsequent fractures.

Considering index fractures, compliant patients under treatment at baseline had lower CTX-1 levels than non-compliant patients (p=0.052). Patients who were compliant to treatment at six, 12 and 18 months also had lower CTX-1 levels than non-compliant patients (p=0.000). When index fractures were divided into fracture sites, regardless of CTX-1 suppression target level (i.e. CTX-1< 0.3 or 0.2 ng/mL), significant CTX-1 suppression was observed in non-hip and non-vertebral (NHNV) fractures at six, 12 and 18 months (p0.05). No clinically relevant difference was observed between the profile of patients with and without subsequent fractures.

The correlation between serum CTX-1 at the time of fracture and at six, 12, 18 months and the perceived compliance to treatment was validated for NHNV fractures supporting the concept of the available treatments and their effects on bone remodeling for this type of fracture. The correlation was not validated for hip neither for vertebral fracture. There was no correlation between CTX-1 levels and subsequent fracture risk.


A. Hart L. Epure S.G. Bergeron O. Huk D. Zukor J. Antoniou

Hip fractures are among the most common orthopaedic injuries and represent a growing burden on healthcare as our population ages. Despite improvements in preoperative optimisation, surgical technique and postoperative care, complication rates remain high. Time to surgery is one of the few variables that may be influenced by the medical team. The aim of the present study was to evaluate the impact of time to surgery on mortality and major complications following surgical fixation of hip fractures.

Utilising the American College of Surgeons' National Quality Improvement Program (NSQIP) database, we analysed all hip fractures (femoral neck, inter-trochanteric, and sub-trochanteric) treated from 2011 to 2013 inclusively. We divided patients into three groups based on time to surgery: less than one day (<24h), one to two days (24–48h), and two to five days (48–120h). Baseline characteristics were compared between groups and a multivariate analysis performed to compare 30-day mortality and major complications (return to surgery, deep wound infection, pneumonia, pulmonary embolus, acute renal failure, cerebrovascular accident, cardiac arrest, myocardial infarction, or coma) between groups.

A total of 14,730 patients underwent surgical fixation of a hip fracture and were included in our analysis. There were 3,475 (24%) treated <24h, 9,960 (67%) treated 24–48h, and 1,295 (9%) treated 48–120h. Thirty-day mortality and major complication rates were 5.0% and 6.2% for the <24h group, 5.3% and 7.0% for the 24–48h group, 7.9% and 9.7% for the 48–120h group respectively. After controlling for baseline demographic differences between groups (age, sex, race) as well as pertinent comorbidities (diabetes, dyspnea, chronic obstructive pulmonary disease, chronic steroid use, hypertension, cancer, bleeding disorders, and renal failure), time to surgery beyond 48h resulted in greater odds of both mortality (1.45, 95%CI 1.10–1.91) and major complications (1.45, 95%CI 1.12–1.84).

Time to surgery is one of the few variables that can be influenced by timely medical assessment and access to the operation room. Expediting surgery within 48h of hip fracture is of paramount importance as it may significantly reduce the risk of mortality as well as major complications.


N. O'Hara M. Neufeld M. Zhan Y. Zhai H.A. Broekhuyse K. Lefaivre J.M. Abzug G.P. Slobogean

The effect of early surgery on hip fracture outcomes has received considerable study and although it has been suggested that early surgical treatment of these fractures leads to better patient outcomes, the findings are inconclusive. The American College of Surgeon's (ACS) National Surgical Quality Improvement Project (NSQIP) prospectively collects blinded, risk-adjusted patient-level data on surgical patients in over 600 participating hospitals worldwide. The primary objective of this study was to determine the proportion of ACS-NSQIP hospital patients that are currently being treated within the UK's National Institute for Health and Care Excellence (NICE) time to hip fracture surgery benchmark. The secondary objectives were to identify risk factors for missing the benchmark, and determine if the benchmark is associated with improved 30-day patient outcomes.

Patients that underwent hip fracture surgery between 2005–2013 and entered in the ACS-NSQIP database were included in the study. Counts and proportions were used to determine how frequently the NICE benchmark was met. Multivariate regression analysis was used to identify significant predictors of missing the NICE benchmark and determine if missing the benchmark was associated with 30-day mortality/complications rates.

26,006 patients met the study enrolment criteria. 71.4% of patients were treated within the NICE benchmark and 89.4% were treated by post-admission day two. Gender, dyspnea, infectious illness, bleeding disorders, preoperative hematocrit, preoperative platelet count, arthroplasty procedure type, race other than White, and hip fracture diagnosis were all statistically significant predictors of missing the benchmark (p<0.01). Meeting the NICE benchmark was not associated with reductions in major complications (OR=0.93, CI=0.83–1.05, p=0.23), nor a clinically significant difference in postoperative length of stay (LOS) (parameter estimate=0.77, p<0.01); however, it was associated with a decreased 30-day mortality (OR=0.88, CI=0.78–0.99, p=0.03) and the likelihood of minor complications (OR=0.92, CI=0.84–0.995, p=0.04).

ACS-NSQIP hospitals are currently compatible with the NICE benchmark. However, data from the ACS-NSQIP database suggests that surgical treatment within the NICE benchmark may be unnecessarily narrow. Extending the benchmark to post-operative day two did not significantly increase the risk of 30-day mortality and minor complications; nor did it extend the average LOS. Neither the NICE benchmark, nor the extended two-day standard, was associated with reductions in major complications. The findings highlight the importance of further prospective investigation to monitor the effect of time to surgery benchmarks.


T. Frank G. Osterhoff S. Sprague A. Hak M. Bhandari G. Slobogean

The Radiographic Union Score for Hip (RUSH) is an outcome instrument designed to describe radiographic healing of femoral neck fractures. The ability to identify fractures that have not healed is important for defining non-union in clinical trials and predicting patients that likely require additional surgery to promote fracture healing. We sought to determine a RUSH threshold score that defines nonunion at 6-months post-injury. Our secondary objective was to determine if this threshold was associated with increased risk for non-union surgery.

A sample of 248 patients with adequate six-month hip radiographs and complete two-year clinical follow-up were analysed from a multi-national hip fracture trial (FAITH). All patients had a femoral neck fracture and were treated with either multiple cancellous screws or a sliding hip screw. Two reviewers independently determined the RUSH score based on the six-month post-injury radiographs, and agreement was assessed using the Interclass Correlation Coefficient (ICC). Fracture healing was determined by two independent methods: 1) prospectively by the treating surgeon using clinical and radiographic assessments, and 2) retrospectively by a Central Adjudication Committee using radiographs alone. Receiver Operator Curve analysis was used to define a RUSH threshold score that was specific for fracture nonunion.

RUSH score inter-rater agreement was high (ICC: 0.81, 95% CI 0.76 to 0.85). The mean six-month RUSH score for all included patients was 24.4 (SD 3.4). A threshold score of <18 was associated with a greater than 98% specificity for nonunion. Furthermore, patients with a six-month RUSH score below 18 were more the seven-times more likely to require revision surgery for nonunion (Relative Risk: 7.25, 95% CI 2.62 to 20.00).

The six-month RUSH score can effectively be used to communicate when a femoral neck fracture has not healed. The validity of our conclusions was further supported by the increased risk of nonunion surgery for patients below the RUSH threshold. We believe our findings can standardise a definition of nonunion for clinical trials and recommend the use of the RUSH and its <18-point threshold when describing femoral neck nonunion.


P. Kivi A. Juby D. Hanley L. Evens S. Falsetti

In Alberta there are over 2,700 hip fractures per year costing the health system over $24 million in acute care costs alone. 50% of hip fracture patients have had a prior fragility fracture as a result of underlying osteoporosis (OP) that has never been assessed or appropriately treated. The Fracture Liaison Service (FLS) in Alberta aims to improve appropriate osteoporosis care, highlight and address gaps within seniors care through OP management, and provide a geriatric syndrome triage service.

The FLS has developed a linkage with the Emergency Department (ED) geriatric team whereby hip fracture patients are identified in ED using a screening tool for geriatric syndromes prior to their surgery, allowing the FLS to follow through on comorbidities likely contributing to falls. An inpatient orthopaedic unit with a dedicated Registered Nurse (RN) and a Care of the Elderly Physician see and assess hip fracture patients after surgery for appropriate osteoporosis management and treatment. Screening tools have been developed to quickly detect underlying dementia and to quantify frailty to determine life expectancy and appropriate osteoporosis therapy. Patients are also referred to Geriatric Assessment Units and fall prevention programs. Patients are then contacted in the community at 3, 6,9,12 months by the FLS RN to follow up on osteoporosis therapy, and arrange other needed tests (i.e. bone mineral density, vitamin D) as needed. Information is sent to their family physician with all results. Prior to the patient's discharge from the FLS at one year, a final hand-over letter from the program will be provided outlining the plan of care for the patient.

The FLS launched in June 2015 at the Misericordia hospital in Edmonton, Alberta (with plans to expand provincially). Currently 3 out of 4 hip fracture patients per week are being identified in the ED. Ninety-eight hip fracture patients have been identified post-surgery, with 71 patients eligible for enrollment in the program (five deceased patients). Sixty-six (50%) of those enrolled were discharged on osteoporosis medication compared to 8% prior to the program initiation. Seventeen (26%) of those were new medication starts. Of those not started, 7(11%) was patient choice. 11(31%) will be reassessed at 3 months for appropriate therapy. Nineteen (27%) of patients were referred to other inpatient or outpatient programs (i.e. falls, memory). Three month follow up calls have begun with patients for further data collection and a full 1 year qualitative and quantitative evaluation will be done.

The implementation of an FLS with dedicated personnel to proactively manage and treat patients with appropriate investigations and interventions can close the care gap that exists in OP care. It also addresses gaps in senior care and provides appropriate referral to community geriatric programs, to improve quality of life and prevent future fractures.


N. Greidanus D. Garbuz S. Konan C. Duncan B. Masri

Revision surgery for pelvic discontinuity in the presence of bone loss is challenging. The cup-cage reconstruction option has become popular for the management of pelvic discontinuity in the recent years. The aim of this study was to review the clinical, radiological and patient reported outcomes with the use of cup cage construct for pelvic discontinuity at our institution.

Twenty-seven patients (27 cup-cage reconstructions) were identified at median 6-year (minimum 2 year, maximum 10 years) follow up. Eight were female patients. The median age was 77 years [mean 72, range 37–90, SD 13.6]. There were 5 deaths and 2 were lost to follow up.

Two patients were converted to excision arthroplasty; one for infection and one for failure of the construct. A further 3 patients required revision for instability but the cup cage construct was not revised (2 revisions of cemented cups to a constrained cup and one revision of proximal modular component of the femoral prosthesis). Revision of the cup cage construct was not necessary in any of these cases. We noted excellent pain relief (mean WOMAC pain 85.6) and good functional outcome (mean WOMAC function 78.2, mean UCLA 5, mean OHS 78.6). Patient satisfaction with regards pain relief; function and return to activities were noted to be excellent. Radiological changes were noted in further 4 patients (cup migration in one case; fracture of ischial spike in one case and breakage of the cage screws in 2 patients). No migration of the construct was noted in any of the cases.

In conclusion, the cup cage construct is an excellent method of dealing with complex pelvic discontinuity. Our study suggests a low failure rate; high patient satisfaction and pain relief and moderate functional outcome at median 6 year follow up.


C. Burnell B. Flynn T. Gascoyne K. Stockwell T.R. Turgeon

Non-large head Metal-on-metal (MoM) hip replacements were seen as a solution to concerns about implant wear in younger patients. Mid-term loosening of once well-fixed hydroxyapatite (HA) coated femoral stems was recently observed in select MoM patients upon revision surgery. Accordingly, an implant retrieval study was undertaken to examine the incidence of aseptic loosening of in HA-coated femoral stems with MoM, ceramic on ceramic (CoC) and metal on polyethylene (MoP) bearing couples.

A single-centre implant retrieval lab reviewed 44 hydroxyapatite (HA)-coated titanium wedge taper stems of the same design retrieved over a period of 9 years. Ten were MoM articulations, 23 MoP and 11 CoC. Head sizes ranged from 28 to 40 with only four 40mm heads, all of which were MoM. Reason for revision, duration of implantation, femoral head size, patient age and body mass index was recorded for each retrieval. Goldberg corrosion scores were determined for the taper surfaces of each retrieval, with ‘0’ indicating no corrosion and ‘3’ indicating severe corrosion. Logistic regression analysis, Wilcoxan Rank Sum and Fischer's exact test were used for statistical analysis.

Aseptic loosening was the listed reason for revision in 18 of 44 cases. MoM bearing was associated with increased probability of aseptic loosening (Odds ratio 7.1 (95%CI 1.1–47.0) p=0.042). Severity of corrosion was also associated with aseptic loosening (Odds ratio 2.75 (95%CI 1.1–6.6) p=0.02). Head size and patient age had no correlation. Median time to revision of implants for aseptic loosening was 4.5 years (range: 4.2–7.0 years) for MoM versus 1.4 years (range: 0.3–3.0) for other bearing couples (p=0.004). Aseptic loosening was categorised as early (<=2 years) or mid-term (>2 years). No MoM hips were revised for aseptic loosening in the first 2 years while 8 of the 11 mid-term revisions had MoM articulations (p=0.004). Taper corrosion was more severe in mid-term aseptic loosing cases (p=0.049).

MoM HA-coated hip replacements appear to be associated with increased mid-term aseptic loosening compared to other bearing couples. Patients with MoM HA-coated hip replacements should be monitored regularly beyond the initial 1 to 2 years following surgery. Future analyses will examine the presence and progression of femoral radiolucency prior to revision surgery to determine an approximate timeline of stem loosening in this patient cohort. This research highlights the importance of implant retrieval programs to assess post-revision implant characteristics for early identification of possible device issues.


M. Nyland B. Lanting L. Somerville E. Vasarhelyi D. Naudie J. McAuley R. McCalden S. MacDonald J. Howard

Infection following total hip arthroplasty (THA) represents a devastating complication and is one of the main causes for revision surgery. This complication may be treated by irrigation and debridement with head and polyethylene exchange (IDHPE) or a two-stage revision (2SR). Previous studies have reported on the eradication success rates but few have reported patient outcome scores. The purpose of this study was to report patient outcome scores for both IDHPE and 2SR and compare these to a non-infected matched cohort. We hypothesised that both cohorts would have worse outcomes than the control group, and that those who failed an initial IDHPE and required a 2SR would have a worse outcome than those treated initially with a 2SR.

A retrospective review identified 137 patients from our institutional arthroplasty database who had an infected primary THA between 1986–2013. We excluded patients with less than one-year follow-up. Mean follow-up was 60 months (12–187 months). A control cohort was identified and matched according to age and Charlton Comorbidity Index (CCI). Harris Hip Scores, Short Form 12 and WOMAC scores were compared between our control group and our infected cohort.

Sixty-eight patients were treated with a 2SR and 69 patients were treated with an IDHPE. There was a 59% success rate in eradicating the infection with an IDHPE. All of the 28 patients who failed an IDHPE later went on to a 2SR. Outcome scores for the 2SR cohort were significantly worse than the non-infected controls (p0.05). There was no difference in outcome scores when comparing our 2SR cohort to our failed IDHPE (p>0.05).

Previous studies have focused on eradication rates. However, it is important to consider patient outcome scores when deciding the best treatment. Infected patients treated with a successful IDHPE had similar outcomes to non-infected patients. Patients that failed IDHPE and went onto 2SR had similar outcomes to those that had a 2SR alone. IDHPE should still be considered in the treatment algorithm of infected THA.


K. Stampe L. Beaupre E. Masson G. O'Connor M. Clark M. Joffe L. Boychuk G. Lavoie

Periprosthetic joint infection is a significant complication of total hip arthroplasty. The PRSThesis of Antibiotic Loaded Acrylic Cement (PROSTALAC) system can improve health related quality of life during a two step treatment approach for infection resolution. We investigated quality of life with the PROSTALAC in situ and also compared subjects who underwent second stage surgery with those who retained the PROSTALAC on a long term basis.

Twenty nine subjects were enrolled pre-PROSTALAC insertion, recording demographics, physical demand level and comorbidities. Subjects were then followed out to 24 months with either the PROSTALAC in situ or post revision for those who underwent the second stage surgery. Quality of life was evaluated using the Western Ontario McMaster Osteoarthritis Index (WOMAC) and RAND 36-Item Health Survey (RAND-36). Infection resolution was also determined for all subjects enrolled.

Three subjects died and 22/26 (84%) completed the evaluation. Overall 26 (85%) infections resolved. Following PROSTALAC insertion, WOMAC pain and function scores improved within three to six months and did not change out to 24 months. Physical function, bodily pain and vitality also significantly improved within three to six months postoperatively. Only seven (32%) subjects underwent second stage surgery. These individuals were more likely to be high demand (p=0.03) and trended towards being younger, male, with fewer comorbidities and lower BMI (p<0.10). There was no difference in WOMAC scores at 24 months between those who underwent second stage revisions and those who retained the PROSTALAC.

The use of a PROSTALAC implant improves health related quality of life. Long term retention of the PROSTALAC implant may be appropriate for low demand patients and considered for potentially high risk surgical candidates.


R. Philippot B. Boyer T. Neri F. Farizon

The main causes of total hip arthroplasty (THA) revisions are loosening and instability. Use of a dual mobility cup cemented in a acetabular reconstruction cage device limits the risk of instability and does not hinder the acetabular fixation during THA revisions. The objective of this study was to analyse a retrospective series of 123 THA revisions with antiprotusio cage and dual mobility socket.

Patients and methods: At a mean follow-up of 10 years, we analysed a continuous series of 123 revisions using a reconstruction device (87 Kerboull cross-plates, 12 Burch-Schneider antiprotrusio cages, 24 custom-fit Novae ARM cages associated in all cases with a Novae Stick dual mobility cup cemented into the cage). There were 80 women and 43 males. The mean age at the surgery was 69.2 years old.

PMA score increased from 9.6 +/− 3.06 preoperatively to 14.2 +/− 2. at the follow-up. 9 early dislocations occurred and one late dislocation. At the last follow-up, the X-rays showed nine hardware failures, including one cross-plate fracture, one hook fracture, and one flange fracture. Analysis of the radiological position of the cup showed a mean lowering of 13 mm and a 7 mm lateralisation compared to the preoperative position. 2 revisions for aseptic loosening and 3 for septic loosening were performed.

This study confirms the advantage of dual mobility cups during acetabular reconstruction cemented in antiprotrusio cages as a way to limit, without eliminating, the risk of dislocation. Therefore cemented fixation of dual mobility cups in cages appears to be a reliable short-term option.


É.L. Belzile M.O. Dion M. Assayag M. Angers S. Pelet

Modularity in femoral revision stems was developed to reduce subsidence, leg length discrepancy and dislocation experienced in revision surgery. The Wagner SL Revision Stem (Zimmer, Warsaw, IN) has been known for excellent bony fixation and proximal bony regeneration, but the third-generation proportional neck offset and 135° neck-shaft angle has an unknown track record. Our aim is to study the effect of these design modifications on stem subsidence, dislocation rate and stem survival.

We reviewed 76 consecutive femoral revisions (70 patients; 50 M: 20 W; 67.7 yo [range; 37.7 – 86.6 yo]) with the Wagner SL implanted at our institution (2004–2012). No patient was lost to follow-up, but nine had died, and one patient was excluded for a Paprosky type I femoral bone defect. This leaves us 66 hips (60 patients) at 2 to 9.5 years of follow-up (mean 55 months; range, 24–114 months). Indications for revisions included aseptic stem loosening (62.1%), infection (13.6%), acetabular loosening (12.1%), recurrent dislocation (4.5%), periprosthetic (4.5%) and stem fracture (1.5%), and chondrolysis (1.5%). Patients were actively followed up at regular intervals to ascertain revision status and outcome measures including the Merle d'Aubigné (n=53), WOMAC questionnaires (n=59) and radiographs (n=66). Radiographs were evaluated for stem subsidence (mm).

One of the surviving 66 stems was revised for recurrent deep infection (1.5%). No patient underwent revision of the femoral stem for aseptic loosening or subsidence. The mean preoperative WOMAC scores (P: 12.8; S: 5.6; F: 51.8) had improved significantly at follow-up (P: 9.7;, S: 4.3; F: 37.6) (p<0.05). The mean Merle D'Aubigné score went from a pre-op of 8.2 (SD: 2.8; range 1 to 14) to a mean of 15.3 (SD: 2.6; range 7 to 18) (p<0,05) at the latest follow-up. During the follow-up period, 3 hips dislocated (4.5%). Each event happened prior to six months after surgery. Only one of these cases dislocated twice. Closed reduction was performed in all cases. None required revision surgery subsequently, and they all remained stable. The stem survivorship is 98.4% at 5 years (0.95 CI: 93–100) and 97.4% at 7.5 years (0.95 CI: 88.9–100). Stem subsidence of 0 to 5 mm was considered as not clinically significant (n=20; 30%). Stem subsidence of 5 to 10 mm occurred in 5 hips (7.6%)and stem subsidence greater than 10 mm only occurred in one hips (1.5%).

The third generation Wagner SL conical revision femoral stem has a lower rate of complication than its preceding generations, and is comparable to modular stems performance reported in current literature. These results motivate the authors to continue using monoblock conical revision femoral stems.


N. Greidanus S. Konan C. Duncan B. Masri D. Garbuz

In revision total hip arthroplasty (THA), acetabular reconstruction while dealing with severe bone loss is a challenge. The porous tantalum revision acetabular shells have been in use for the past decade. Several reports have documented successful use at early to mid-term follow up. There is, however, very little literature around the long-term survival and quality of life outcome with the use of these shells.

We reviewed the results of 46 acetabular revisions with Paprosky 2 and 3 acetabular bone defects reconstructed with a hemispheric, tantalum acetabular shell and multiple supplementary screws. There were 31 females. Average age at revision was 64 years (range 23–85 years). The mean and median follow up was 11 years (range 10–12 years, SD 1). Morselised femoral allograft was used in 34 hips to fill contained cavitary defectes. Bulk femoral allografting was performed in 2 hips.

At a minimum follow-up of 10 (range 10–12) years, the survivorship of the porous tantalum acetabular shell, with revision of the shell as end point was 96%. The minimum 10-year survivorship with hip revision for any reason as end point was 92%. We noted excellent pain relief (mean WOMAC pain 92.6) and good functional outcome (mean WOMAC function 90.3, mean UCLA 5); and generic quality of life measures (mean SF-12 physical component 48.3; mean SF-12 mental component 56.7). Patient satisfaction with pain relief, function and return to recreational activities were noted to be excellent.

Cementless acetabular revision with the tantalum acetabular shell demonstrated excellent clinical and quality of life outcomes at minimum 10-year follow-up. As far as we are aware this is the first report of minimum 10-year follow up of use of this technique for revision hip arthroplasty.


A. Almaawi L. Bayam M. Duchesne-L'Heureux D. Lusignan M. Lavigne P.A. Vendittoli

Management of pseudotumours associated with MoM THA can be difficult and complications are frequent. The functional outcome of patients after revision surgery may be suboptimal. The objective of this study was to assess our experience with revisions of failed MoM THA due to pseudotumours.

78 hips were diagnosed with pseudotumours in 70 patients following metal-on-metal hip replacements. Of these, 68 MoM THA were revised in 62 patients. Pre operative symptoms, radiographic analysis, metal ion levels, MRI results, intra-operative findings, WOMAC scores, the satisfaction level and the complication rate were recorded.

Five patients had a resurfacing arthroplasty as their primary implants while the remaining 63 hips in 57 patients had MoM THA of different brands. The average time between the primary and revision surgery was 69 months (range 15–120). The average age at revision was 59 years (43–87). The mean follow-up was 24 months (range 2–73). 36 patients had minimal one year follow-up. Most lesions consisted of cystic changes and solid lesions were observed in 19 patients. In 57 hips, the pseudotumours were located posteriorly or postero-laterally around the greater trochanter. Intra operatively, muscle necrosis was observed in 15(22%) patients. Most THA cases demonstrated wear and corrosion at the head neck junction of the femoral implants. Thirty-five patients (44.9%) had greater than 50 degrees of cup abduction, including 10 patients (12.8%) with an abduction angle greater than 60 degrees. The average pre operative and postoperative Co ion levels were 27.46 ug/L (range 0.36–145.6) and 2.46 (range 0.4–12.48), respectively. Post revision, a total of 10 hips (14.7%) sustained a dislocation, with seven (10.3%) of them experiencing recurrent dislocations. In 8/10 hips, the femoral head size was 36mm or greater. Revision for dislocation occurred in seven(10.3%) patients. Three(4.4%) deep and one(1.47%) superficial infections occurred and deep infections were re-operated. One(1.47%) fracture of the greater trochanter and one (1.47%) psoas tendinitis did not need revision. Therefore, a total of 10 patients (14.7%) were reoperated. 6 revisions for instability were performed in the first 34 patients, while 1 were done in the last 34 patients. At one year post revision surgery, the mean WOMAC score was 19.68 (range 0–48). In comparison, the mean WOMAC score of the same patients one year after their primary surgery was 8.1 (0–63). Patient satisfaction level of patients one year post revision surgery was 7.61 (range 5–10) compared to 4.15 (range 0–7) pre-revision one.

The complication rate after revision of pseudotumours is high. Most re revisions occurred secondary to instability despite the use of larger femoral heads. The functional outcome at one year post revision seems to be lower than that seen after primary THA but similar to other revisions in the literature. Experience in the management of these patients may reduce the complication rate.


E.H. Schemitsch D. Walmsley M. McKee A. Nauth J.P. Waddell

Proximal femur fractures are increasing in prevalence, with femoral neck (FN) and intertrochanteric (IT) fractures representing the majority of these injuries. The salvage procedure for failed open reduction internal fixation (ORIF) is often a conversion to total hip arthroplasty (THA). The use of THA for failed ORIF improves pain and function, however the procedure is more challenging. The aim of this study was to investigate the clinical and radiographic outcomes in patients who have undergone THA after ORIF.

This retrospective case-control study compared patients who underwent THA after failed ORIF to a matched cohort undergoing primary THA for non-traumatic osteoarthritis. From 2004 to 2014, 40 patients were identified. The matched cohort was matched for date of operation, age, gender, and type of implant. Preoperative, intraoperative, and postoperative data were collected and statistical analysis was performed.

The cohort of patients with a salvage THA included 18 male and 22 female patients with a mean age of 73 years and mean follow up of 3.1 years. Those with failed fixation included 12 IT fractures and 28 FN fractures. The mean time between ORIF and THA was 2.1 years for IT fractures and 8.5 years for FN fractures (p=0.03). The failed fixation group had longer procedures, greater drop in hemoglobin, and greater blood transfusion rate (p<0.05). There was one revision and one dislocation in the failed fixation group with no revisions or dislocations in the primary THA group. Length of admission, medical complications, and functional outcome as assessed with a standardised hip score and were found not to be statistically different between the groups.

Salvage THA for failed initial fixation of proximal femur fractures yields comparable clinical results to primary THA with an increased operative time, blood loss, and blood transfusion rate.


N.A. Stavropoulos L.M. Epure D.J. Zukor O. Huk J. Antoniou

Hip resurfacing offers an attractive alternative to conventional total hip arthroplasty in young active patients. It is particularly advantageous for bone preservation for future revisions. Articular Surface Replacement (ASR) is a hip resurfacing prosthesis manufactured by DePuy Orthopaedics Inc. (Warsaw, IN). The manufacturer voluntarily recalled the ASR system in 2010 after an increasing number of product failures. The present study aimed to determine the long-term results in a large cohort of patients who received the ASR prosthesis.

Between February 2004 and August 2010, 592 consecutive hip resurfacings using the ASR (DePuy Orthopaedics Inc., Warsaw, IN) resurfacing implant were performed in 496 patients (391 males and 105 females). The mean age of the patients at the time of the surgery was 54 (range: 25 to 74) years. Osteoarthritis was the most common diagnosis in 575 hips (97.1%). The remaining patients (2.9%) developed secondary degenerative disease from ankylosing spondylitis, avascular necrosis, developmental hip dysplasia, and rheumatoid arthritis. Clinical and radiographic information was available for all patients at the last follow up. Cobalt (Co) and chromium (Cr) levels were measured in 265 patients (298 hips) by inductively coupled plasma-mass spectrometry (ICP-MS).

The average follow up of the study was 8.6 years (range: 5.2 to 11.6 years). The mean Harris hip and UCLA scores significantly improved from 44 and 2 pre-operatively to 85.3 and 7.1 respectively. The median Co and Cr ion level was 3.81 microgram per liter and 2.15 microgram per liter respectively. Twenty-seven patients (5.4%) were found to have blood levels of both Co and Cr ions that were greater than 7 microgram per liter. Fifty-four patients (9.1%) were revised to a total hip arthroplasty. Kaplan-Meier survival analysis showed a survival rate of 87.1% at 8.6 years with revision for any cause and 87.9% if infection is removed. A significantly higher survival rate was observed for the male patients (90.2%, p <0.0001) and for the patients with ASRs with femoral heads diameters larger than 52 mm (90.1%, p=0.0003).

This study confirms that patient selection criteria are of great importance to the overall survivorship of hip resurfacing arthroplasty. Improved clinical results have been reconfirmed with the use of larger diameter femoral heads.


M.W. Camp J. Adamich A. Howard

Although most uncomplicated paediatric fractures do not require routine long-term follow-up with an orthopaedic surgeon, practitioners with limited experience dealing with paediatrics fractures will often defer to a strategy of unnecessary frequent clinical and radiographic follow-up. Development of an evidence-based clinical care pathway may help reduce unnecessary radiation exposure to this patient population and reduce costs to patient families and the healthcare system.

A retrospective analysis including patients who presented to SickKids hospital between October 2009 and October 2014 for management of clavicle fractures was performed. Patients with previous clavicle fractures, perinatal injury, multiple fractures, non-accidental injury, underlying bone disease, sternoclavicular dislocations, fractures of the medial clavicular physis and fractures that were managed at external hospitals were excluded from the analysis. Variables including age, gender, previous injury, fracture laterality, mechanism of injury, polytrauma, surgical intervention and complications and number of clinic visits were recorded for all patients. Radiographs were analysed to determine the fracture location (medial, middle or lateral), type (simple or comminuted), displacement and shortening.

339 patients (226 males, 113 females) with an average age of 8.1 (range 0.1–17.8) were reviewed. Diagnoses of open fractures, skin tenting or neurovascular injury were rare, 0.6%, 4.1%, and 0%, respectively. 6 (1.8%) patients underwent surgical management. All decisions for surgery were made on the first consultation with the orthopaedic surgeon. For patients managed non-operatively, the mean number of clinic visits including initial consultation in the emergency department was 2.0 (±1.2). The mean number of radiology department appointments was 4.1 (± 1.0) where patients received a mean number of 4.2 (±2.9) radiographs. Complications in the non-operative group were minimal; 2 refractures in our series and no known cases of non-union. All patients achieved clinical and radiographic union and returned to sport after fracture healing.

Our series suggests that the decision to treat operatively is made at the initial assessment. If no surgical indications were present at the initial assessment by the primary-care physician, then routine clinical or radiographic follow up is unnecessary. Development of a paediatric clavicle fracture pathway may reduce patient radiation exposure and reduce costs incurred by the healthcare system and patients' families without jeopardising patient outcomes.


K. Mulpuri A. Dobbe E. Schaeffer F. Miyanji C. Alvarez A. Cooper C. Reilly

Closed reduction and percutaneous pinning has become the most common technique for the treatment of Type III displaced supracondylar humerus fractures in children. The purpose of this study was to evaluate whether the loss of reduction in lateral K wiring is non-inferior to crossed K wiring in this procedure.

A prospective randomised non-inferiority trial was conducted. Patients aged three to seven presenting to the Emergency Department with a diagnosis of Type III supracondylar humerus fracture were eligible for inclusion in the study. Consenting patients were block randomised into one of two groups based on wire configuration (lateral or crossed K wires). Surgical technique and post-operative management were standardised between the two groups. The primary outcome was loss of reduction, measured by the change in Baumann's angle immediately post –operation compared to that at the time of K wire removal at three weeks. Secondary outcome data collected included Flynn's elbow score, the humero-capitellar angle, and evidence of iatrogenic ulnar nerve injury. Data was analysed using a t-test for independent means.

A total of 52 patients were enrolled at baseline with 23 allocated to the lateral pinning group (44%) and 29 to the cross pinning group (56%). Six patients (5 crossed, 1 lateral) received a third wire and one patient (crossed) did not return for x-rays at pin removal and were therefore excluded from analysis. A total of 45 patients were subsequently analysed (22 lateral and 23 crossed). The mean change in Baumann's angle was 1.05 degrees, 95% CI [-0.29, 2.38] for the lateral group and 0.13 degrees, 95% CI [-1.30, 1.56] for the crossed group. There was no significant difference between the groups in change in Baumann's Angle at the time of pin removal (p = 0.18). Two patients in the crossed group developed post-operative iatrogenic ulnar nerve injuries, while none were reported in the lateral group.

Preliminary analysis shows that loss of reduction in Baumann's angle with lateral K wires is not inferior to crossed K wires in the management of Type III supracondylar humerus fractures in children. The results of this study suggest that orthopaedic surgeons who currently use crossed K wires could consider switching to lateral K wires in order to reduce the risk of iatrogenic ulnar nerve injuries without significantly compromising reduction.


K. Smit A. Hines M. Elliott D. Sucato R.L. Wimberly A. Riccio

Infection and re-fracture are well-described complications following open paediatric forearm fractures. The purpose of this paper is to determine if patient, injury, and treatment characteristics can be used to predict the occurrence of these complications following the surgical management of paediatric open forearm fractures.

This is an IRB-approved retrospective review at a single-institution paediatric level 1 trauma centrefrom 2007–2013 of all open forearm fractures. Medical records were reviewed to determine the type of open fracture, time to administration of initial antibiotics, time from injury to surgery, type of fixation, length of immobilisation, and complications. Radiographs were studied to document fracture characteristics.

262 patients with an average age of 9.7 years were reviewed. There were 219 Gustillo-Anderson Type 1 open fractures, 39 Type 2 fractures, and 4 Type 3 fractures. There were 9 infections (3.4%) and 6 re-fractures (2.3%). Twenty-eight (10.7%) patients returned to the operating room for additional treatment; 21 of which were for removal of implants. Contaminated wounds, as documented within the medical record, had a greater chance of infection (21% vs 2.2%, p=0.002). No difference in infection rate was seen with regard to timing of antibiotics (p=0.87), timing to formal debridement (p=0.20), Type 1 versus Type 2 or 3 open fractures (3.4% vs 5.0%, p=0.64), 24 hours vs. 48 hours of post-operative IV antibiotics (5.2% vs 3.5%, p=0.53), or when comparing diaphyseal, distal, and Monteggia fracture patterns (3.6 vs 2.9% vs 5.9%, p=0.81). There was no difference in infection rate when comparing buried or exposed intramedullary implants (3.5% vs 4.2%, p>0.99). Rate of re-fracture was not increased based on type of open wound (p>0.99) or fracture type (0.4973), although 5 of the 6 re-fractures were in diaphyseal injuries.

In this series of open paediatric both bone forearm fractures, initial wound contamination was a significant risk factor for subsequent infection. The rate of infection did not vary with timing of antibiotics or surgery, type of open fracture, or length of post-operative antibiotics. A trend to higher re-fracture rates in diaphyseal injuries was noted. Surgeons should consider planned repeat irrigation and debridement for open forearm fractures with obviously contaminated wounds to reduce the subsequent infection risk.


R. Pathy E. Dodwell D.W. Green D.M. Scher J.S. Blanco S.M. Doyle A. Daluiski E.L. Sink

There is currently no standardised complication grading classification routinely used for paediatric orthopaedic surgical procedures. The Clavien-Dindo classification used in general surgery was modified and validated in 2011 by Sink et al. and has been used regularly to classify complications following hip preservation surgery. The aim of this study was to adapt and validate Sink et al.'s modification of the Clavien-Dindo classification system for grading complications following surgical interventions of the upper and lower extremities and spine in paediatric orthopaedic patients.

Sink et al.'s modification of the Clavien-Dindo classification system was further modified for paediatric orthopaedic procedures. The modified grading scheme was based on the treatment required to treat the complication and the long term morbidity of the complication. Grade I complications do not require deviation from standard treatment. Grade II complications deviate from the normal post-operative course and require outpatient treatment. Grade III complications require investigations, re-admission or re-operation. Grade IV complications are limb or life threatening or have a potential for permanent disability (IVa: with no long term disability and IVb: with long-term disability). Grade V complications result in death. Forty-five complication scenarios were developed. Seven paediatric orthopaedic surgeons were trained to use the modified system and they each graded the scenarios on two occasions. The scenarios were presented in a different random order each time they were graded. Fleiss' and Cohen's k statistics were performed to test for inter-rater and intra-rater reliabilities, respectively.

The overall Fleiss' k value for inter-rater reliability was 0.772 (95% CI, 0.744–0.799). The weighted k was 0.765 (95% CI, 0.703–0.826) for Grade I, 0.692 (95% CI, 0.630–0.753) for Grade II, 0.733 (95% CI, 0.671–0.795) for Grade III, 0.657(95% CI, 0.595–0.719) for Grade IVa, 0.769 (95% CI, 0.707–0.83) for Grade IVb and 1.000 for Grade V (p value <0.001). The Cohen's k value for intra-rater reliability was 0.918 (95% CI, 0.887–0.947). These tests show that the adapted classification system has high inter- and intra-rater reliabilities for grading complications following paediatric orthopaedic surgery.

Given the high intra- and inter-rater reliability and simplicity of this system, adoption of this grading scheme as a standard of reporting complications in paediatric orthopaedic surgery could be considered. Since the evaluation of surgical outcomes should include the ability to reliably grade surgical complications, this reproducible, reliable system to assess paediatric surgical complications will be a valuable tool for improving surgical practices and patient outcomes.


K. Rooks H. Hansen J. Norton A. Dzus L. Allen D. Hedden

The evolution of operative technology has allowed correction of complex spinal deformities. Neurological deficits following spinal instrumentation is a devastating complication and the risk is especially high in those with complex sagittal and coronal plane deformities. Prior to intraoperative evoked potential monitoring, spinal cord function was tested using the Stagnara Wake up test, typically performed after instrumentation once the desired correction has been achieved. This test is limited as it does not reflect the timeframe in which the problem occurred and it may be dangerous to some patients. Intraoperative neuromonitoring allows timely feedback of the effect of instrumentation and curve correction on the spinal cord. Pedicle screws that are malpositioned can result in poor fixation or neuronal injury. Evoked EMG monitoring can aid in accurate placement. A positive EMG response can alert the surgeon to a potential pedicle breech and allow them to reassess the placement of their hardware intraoperatively. The stimulation threshold is affected by the amount of surrounding bone acting as an insulator to electrical conduction and is variable in different regions of the spine. In the non-deformed, lumbar spine stimulation thresholds have been established. Such guidelines have not been well-developed for the thoracic spine, or for severely scoliotic spines. Thus our primary objective was to compare the stimulation threshold of the apical pedicle on the concave side to the stimulation threshold of the pedicles at the upper and lower instrumented levels.

Intraoperative EMG stimulation thresholds were done at 192 apical pedicles on the concave side of the deformity and then compared to those thresholds found at 169 terminal level pedicles. Only pedicles for which a stimulation threshold was found were reported and excluded those where a breech was suspected. The lowest stimulation required for an EMG response was documented to a maximum stimulation of 20 mA.

The mean threshold at the apex was 16.62 milliamps (mA) compared to 18.25mA at the terminal levels. This was compared with the t-test and showed a statistically significant difference (p<0.05).

In this study we report only the thresholds for the concave side, the pedicle that is most likely to be reduced in size. The threshold for stimulation is reduced compared to those seen at the highest and lowest instrumented level. Most of the apexes are located in the mid-thoracic spine with the highest instrumented levels being in the high thoracic spine and the lowest levels being in the lumbar spine. This study provides preliminary evidence that the apical, concave pedicle has a lower threshold than the end pedicles and one cannot rely on established thresholds from different areas of the spine. The surgeon should be cognisant of these differences when instrumenting at the apical level. Ongoing work is examining the convex apex threshold as well as the relationship between the effect of age and a diagnosis other than adolescent idiopathic scoliosis.


J.A. Mortimer J. Norton A. Dzus L. Allen

To examine the effect of lateral spine curvature on somatosensory evoked potentials (SSEP) in patients with adolescent idiopathic scoliosis (AIS) compared to normal controls. We hypothesise that patients with AIS will show increased latency in their SSEPs when bending into their curve suggesting that their spinal cord is more sensitive to this increased lateral curvature.

Patients were recruited from the paediatric scoliosis clinic in a single centre. Inclusion criteria were: diagnosis of AIS, age 10–18 years, major thoracic curve measuring greater than 10 degrees on Cobb measurement, and undergoing nonoperative management. Exclusion criteria were: any detectable neurologic deficit, and previous surgery on the brain or spine. SSEP recordings were obtained via stimulation of the posterior tibial nerve with surface electrode and measurement of the cortical response over the scalp. All recordings were performed three times: with the patient in neutral standing and maximum right and left side bending.

SSEP recordings show that when AIS subjects bend into their curve, latency slows by an average of 0.5ms. However there was a bimodal distribution with most subjects showing minimal change (3ms). This subset was statistically different from both a control group, and the larger AIS group.

There appears to be a subset of patients with AIS who have subclinical spinal cord dysfunction demonstrated by abnormal SSEPs. This may place these patients at slightly higher risk of neurologic injury at the time of surgery.


M. Kadhim R. El-Hawary M. Vitale J. Smith A. Samdani J. Flynn

To evaluate the efficacy of VEPTR in preventing further progression of scoliosis without impeding spinal growth in the treatment of children with progressive early onset scoliosis (EOS) without rib abnormalities.

Prospective, multi-center, observational cohort study on patients with EOS treated with VEPTR with 2-year follow up. Data were analysed based on measurements done pre-implant, immediate post-op and at 2-yr f/u.

Sixty-three patients met inclusion: 35 males and 28 females. Mean age at time of implantation was 6.1±2.4 yrs. Etiologies included congenital (n=6), neuromuscular (n=36), syndromic (n=4), and idiopathic (n=17). Mean follow up was 2.2±0.4 yrs. Scoliosis (72o±18o) decreased after implant surgery (47o±17o) followed by slight increase at 2-yr f/u (57o±18o), p<0.0001.

At 2-yr f/u, VEPTR was effective in treating EOS without rib abnormalities with 86% of patients having an improvement in scoliosis and 94% of patients having an increased spinal height as compared to pre-operatively. VEPTR provided greater than 100% of expected age-matched spine growth and the instrumented spinal segment continued to grow during distraction phase. This large prospective, multicentre study demonstrated the ability of VEPTER to effectively treat EOS without rib abnormalities. Goals of preventing further scoliosis progression and of maintaining normal spine growth were achieved.


M. Camp A.Z. Gladstein A. Shade A. Howard

The primary objective of this study was to determine if paediatric proximal humerus fractures undergo significant displacement resulting in change in management.

A retrospective analysis was performed on children who presented with proximal humeral fractures to our institution between 2009 and 2014. Patients were included if they were diagnosed with a fracture of the proximal humerus in the absence of an underlying bone cyst or pathological condition. Patients with open fractures, multiple fractures, neurologic, or vascular injuries were excluded. The primary endpoint was conversion to operative treatment after initial non-operative management. Secondary endpoints were a healed fracture with acceptable alignment at the final radiographic evaluation, as well as the number of follow-up radiographs obtained after the initiation of non-operative management.

A decision to manage the fracture operatively at the initial presentation was made in 14 out of 239 patients. Of the 225 patients that were initially managed non-operatively, only 1 patient underwent subsequent surgical management. In this series, no non-unions, re-fractures, nor fracture-dislocations were identified.

These data support that the majority of management decisions for paediatric proximal humeral fractures are made at the initial presentation. Once non-operative management is chosen, routine follow-up imaging rarely leads to any change in treatment.


S. Singh D. Bartley M. Cashin T. Carey K.C. DaSilva

The objectives of this study are to ascertain primary caregivers' understanding of risks associated with home trampoline use; to educate caregivers in regard to documented literature based risks associated with home trampoline use; and to evaluate if this information will have any influence on their future regulation of home trampoline use for their children.

One hundred primary caregivers of patients treated in the paediatric orthopaedic surgery outpatient clinic at London Health Sciences centre were surveyed. All caregivers in clinic were invited to participate. The only exclusion criteria was the inability to provide consent. Caregivers' baseline perceptions on the risks associated with home trampoline use were assessed using a questionnaire. Caregivers then received an information pamphlet outlining documented trampoline safety data. They were then sent the same questionnaire to complete within one week of reading the pamphlet. Using our research electronic database capture (Redcap), the results of the surveys were compiled and analysed using spss 22, paired t-test and repeated measures anova. A sample size of 55 was calculated to result in a power of 80%.

Of primary caregivers surveyed, 36% owned a home trampoline, and only 5% had personal experiences with their child sustaining a trampoline injury. Pre-education, when caregivers were asked on a scale of one (not dangerous) to 10 (very dangerous) how dangerous they felt a trampoline was for their child, the average response was six. Post-education, this number changed to eight. Providing education to primary caregivers significantly changed their perceptions on all sections of the questionnaire, yet 47% of primary caregivers were willing to allow their child to use a trampoline at home despite their new understanding of trampoline injury and safety.

Providing education to primary caregivers significantly changed their perceptions on all trampoline safety questions, indicating effective comprehension. Despite caregivers' understanding of the risks associated with home trampoline use, approximately half of the study population continue to permit this activity for their children. There is potential to reduce paediatric orthopaedic injuries associated with home trampoline use if safer trampoline related practices are implemented based on information provided.


R.J. Moore P. Voizard M.L. Nault

Ankle sprains are common athletic injuries, with a peak lifetime incidence between the ages of 15 and 19 years, especially in young males. However, an unclear history, an imprecise physical exam, and unhelpful radiographies lead to frequent misdiagnosis of paediatric ankle traumas, and subsequently, inappropriate treatment. Improper management may lead to residual pain, instability, slower return to physical activity, and long-term degenerative changes. The purpose of this study was to evaluate the initial management and treatment of acute paediatric ankle sprains at our center, a tertiary care paediatric hospital. Our hypothesis was that the initial diagnosis is often incorrect, and treatment varies considerably amongst orthopaedic surgeons.

We conducted a retrospective study of all cases of ankle sprains and Salter-Harris one (SH1) fractures referred to our orthopaedic surgery service between May and August 2014. Exclusion criteria included ankle fractures other than SH1 types, and cases where treatment was initially undertaken elsewhere before referral to our service. Patients were evaluated on a clinical and radiographic basis. Primary outcome was the difference between initial and final diagnosis. Secondary outcome was variation in immobilisation duration for each diagnosis. The main variables we considered were age, sex, mechanism of trauma, referral delay, patient symptoms, physical exam findings, radiographic findings, type and duration of immobilisation, prescription of any medication, and referral to physical therapy.

A total of 3047 patients were reviewed and 31 cases matched our inclusion criteria, comprised of 17 girls and 14 boys, with a mean age of 10.4 years. Patients were seen at a mean of 10.3 days after injury. Initial diagnosis was SH1 fracture in 20 cases, acute ankle sprain in 8 cases, and uncertain in 3 cases. Final diagnosis was SH1 fracture in 11 cases, acute ankle sprain in 13 cases, uncertain in 5 cases, and other in 3 cases. During follow up, 48.5% of cases saw a change in diagnosis. Forty five percent (9/20) of cases initially diagnosed as SH1 fractures proved to be incorrect, with 55.5% (5/9) of these being ultimately diagnosed as acute ankle sprains. Amongst cases initially diagnosed as acute ankle sprains, 37.5% (3/8) received a different final diagnosis. Duration of immobilisation was significantly different between acute ankle sprain and SH1 fracture groups, with an average of 17.3 days and 26.1 days, respectively. Physical therapy was prescribed to 33.3% of acute ankle sprains and 9.1% of SH1 fractures.

Initial distinction between acute ankle sprains and SH1 fractures can be difficult in paediatric ankle trauma. Case management and specific treatments vary considerably, as there is neither an evaluation algorithm nor consensus on treatment of these paediatric pathologies. This study reinforces the need to develop a systematic diagnostic and treatment protocol for paediatric ankle sprains.


D. Martincic

A prospective case control study analysed clinical and radiographic results in patients operated on with the periosteum autologous chondrocyte implantation (ACI) due to cartilage lesions on the femoral condyles over 10 years ago.

31 out of the 45 patients (3 failures, 9 non-responders, 2 others) were available for a continuous clinical (Lyshom/Tegner, IKDC, KOOS) and radiographic (Kellgren-Lawrence) follow-up at 0, 2, 5, and 10 years after the ACI procedure. The patients were sub-grouped into focal cartilage lesions (FL) – 10, osteochondritis dissecans (OCD) – 12, and cartilage lesions with simultaneous ACL reconstruction (ACL) – 9 subgroups.

Lysholm, Tegner, and IKCD subjective scores revealed stable results over the period from 2 to 10 years with a significant improvement toward the pre-operative levels, but the patients had not reached their pre-injury Tegner levels. KOOS profile at 10 years was: Pain 78.6, Symptoms 78.1, Activities of daily living 82.5, Sports 56.9, and Quality of life 55.1. A 10-year IKDC knee examination classified operated knees as: 14 normal, 10 nearly normal, 5 abnormal and 2 severely abnormal. Kellgren-Lawrence scores of 2 and above were found in 10 patients (FL 5, OCD 0, and ACL 5). Seven patients in the group required an arthroscopic re-intervention (3 ACI related, 4 ACI unrelated).

ACI provided safe and stable performance of operated knees over ten years. High incidence of knee osteoarthritis in FL and ACL subgroups, and low incidence in OCD patients indicate that best long performance is expected in localised low-impact cartilage lesions of young patients.