Aim

Treatment recommendations for periprosthetic joint infections (PJI) include surgical debridement, antibiotic therapy or staged revision. In surgical related foot and ankle infections (SR-FAI), implant removal will lead to instability. Debridement is difficult because the implant is outside the joint. Recommendations regarding PJI treatment can therefore not be extrapolated to the treatment of SR-FAI.

Aim

Magnetic resonance imaging (MRI) and 2-[¹⁸F]-fluoro-2-deoxy-D-glucose (¹⁸F-FDG) Positron Emission Tomography, paired with Computed Tomography (PET/CT) are two indicated advanced imaging modalities in the complicated diagnostic work-up of osteomyelitis. PET/MRI is a relatively novel hybrid modality with suggested applications in musculoskeletal infection imaging. The goal of this study was to assess the value of hybrid ¹⁸F-FDG PET/MRI for chronic osteomyelitis diagnosis and surgical planning.

The Banff Patellofemoral Instability Instrument 2.0 (BPII 2.0) is a patient-reported disease-specific quality of life (QOL) outcome measure used to assess patients with recurrent lateral patellofemoral instability (LPI) both pre- and post-operatively. The purpose of this study was to compare the BPII 2.0 to four other relevant patient reported outcome measures (PROMs): the Tampa Scale-11 for kinesiophobia (TSK-11), the pain catastrophizing scale (PCS), a general QOL (EQ-5D-5L), and a return to sport index (ACL-RSI). This concurrent validation sought to compare and correlate the BPII 2.0 with these other measures of physical, psychological, and emotional health. The psychological and emotional status of patients can impact recovery and rehabilitation, and therefore a disease-specific PROM may be unable to consistently identify patients who would benefit from interventions encompassing a holistic and person-focused approach in addition to disease-specific treatment.

One hundred and ten patients with recurrent lateral patellofemoral instability (LPI) were assessed at a tertiary orthopaedic practice between January and October 2021. Patients were consented into the study and asked to complete five questionnaires: the BPII 2.0, TSK-11, PCS, EQ-5D-5L, and the ACL-RSI at their initial orthopaedic consultation. Descriptive demographic statistics were collected for all patients. A Pearson's r correlation coefficient was employed to examine the relationships between the five PROMs. These analyses were computed using SPSS 28.0 © (IBM Corporation, 2021).

One hundred and ten patients with a mean age of 25.7 (SD = 9.8) completed the five PROMs. There were 29 males (26.3%) and 81 females (73.6%) involving 50% symptomatic left knees and 50% symptomatic right knees. The mean age of the first dislocation was 15.4 years (SD = 7.3; 1-6) and the mean BMI was 26.5 (SD = 7.3; range = 12.5-52.6) The results of the Pearson's r correlation coefficient demonstrated that the BPII 2.0 was statistically significantly related to all of the assessed PROM's (p

There was significant correlation evident between the BPII 2.0 and the four other PROMs assessed in this study. The BPII 2.0 does not explicitly measure kinesiophobia or pain catastrophizing, however, the significant statistical relationship of the TSK-11 and PCS to the BPII 2.0 suggests that this information is being captured and reflected. The preliminary results of this concurrent validation suggest that the pre-operative data may offer predictive validity. Future research will explore the ability of the BPII 2.0 to predict patient quality of life following surgery.

Abstract

Aim

Our aim was to evaluate the prevalence and impact of unexpected intraoperative cultures on the outcome of total presumed aseptic knee and hip revision surgery.

Pain and disability following wrist trauma are highly prevalent, however the mechanisms underlying painare highly unknown. Recent studies in the knee have demonstrated that altered joint contact may induce changes to the subchondral bone density and associated pain following trauma, due to the vascularity of the subchondral bone. In order to examine these changes, a depth-specific imaging technique using quantitative computed tomography (QCT) has been used. We've demonstrated the utility of QCT in measuring vBMD according to static jointcontact and found differences invBMD between healthy and previously injured wrists. However, analyzing a static joint in a neutral position is not necessarily indicative of higher or lower vBMD. Therefore, the purposeof this study is to explore the relationship between subchondral vBMDand kinematic joint contact using the same imaging technique.

To demonstrate the relationship between kinematic joint contact and subchondral vBMDusing QCT, we analyzed the wrists of n = 10 participants (n = 5 healthy and n = 5 with previous wrist trauma). Participantsunderwent 4DCT scans while performing flexion to extension to estimate radiocarpal (specifically the radiolunate (RL) and radioscaphoid (RS)) joint contact area (JCa) between the articulating surfaces. The participantsalso underwent a static CT scan accompanied by a calibration phantom with known material densities that was used to estimate subchondral vBMDof the distal radius. Joint contact is measured by calculatinginter-bone distances (mm2) using a previously validated algorithm. Subchondral vBMD is presented using mean vBMD (mg/K2HPO4) at three normalized depths from the subchondral surface (0 to 2.5, 2.5 to 5 and 5 to 7.5 mm) of the distal radius.

The participants in the healthy cohort demonstrated a larger JCa in the RS joint during both extension and flexion, while the trauma cohort demonstrated a larger JCa in the RL during extension and flexion. With regards to vBMD, the healthy cohort demonstrated a higher vBMD for all three normalized depths from the subchondral surface when compared to the trauma cohort.

Results from our preliminary analysis demonstrate that in the RL joint specifically, a larger JCa throughout flexion and extension was associated with an overall lower vBMD across all three normalized layers. Potential reasoning behind this association could be that following wrist trauma, altered joint contact mechanics due to pathological changes (for example, musculoskeletal trauma), has led to overloading in the RL region. The overloading on this specific region may have led to a decrease in the underlying vBMD when compared to a healthy wrist. However, we are unable to conclude if this is a momentary decrease in vBMD that could be associated with the acute healing phase following trauma given that our analysis is cross-sectional. Therefore, future work should aim to analyze kinematic JCa and vBMD longitudinally to better understand how changes in kinematic JCa over time, and how the healing process following wrist trauma, impacts the underlying subchondral bone in the acute and longitudinal phases of recovery.

Revision surgeries for orthopaedic infections are done in two stages – one surgery to implant an antibiotic spacer to clear the infection and another to install a permanent implant. A permanent porous implant, that can be loaded with antibiotics and allow for single-stage revision surgery, will benefit patients and save healthcare resources. Gyroid structures can be constructed with high porosity, without stress concentrations that can develop in other period porous structures [1] [2]. The purpose of this research is to compare the resulting bone and prosthesis stress distributions when porous versus solid stems are implanted into three proximal humeri with varying bone densities, using finite element models (FEM).

Porous humeral stems were constructed in a gyroid structure at porosities of 60%, 70%, and 80% using computer-aided design (CAD) software. These CAD models were analyzed using FEM (Abaqus) to look at the stress distributions within the proximal humerus and the stem components with loads and boundary conditions representing the arm actively maintained at 120˚ of flexion. The stem was assumed to be made of titanium (Ti6Al4V). Three different bone densities were investigated, representing a healthy, an osteopenic, and an osteoporotic humerus, with an average bone shape created using a statistical shape and density model (SSDM) based on 75 cadaveric shoulders (57 males and 18 females, 73 12 years) [3]. The Young's moduli (E) of the cortical and trabecular bones were defined on an element-by-element basis, with a minimum allowable E of 15 MPa. The Von Mises stress distributions in the bone and the stems were compared between different stem scenarios for each bone density model.

A preliminary analysis shows an increase in stress values at the proximal-lateral region of the humerus when using the porous stems compared to the solid stem, which becomes more prominent as bone density decreases. With the exception of a few mesh dependent singularities, all three porous stems show stress distributions below the fatigue strength of Ti-6Al-4V (410 MPa) for this loading scenario when employed in the osteopenic and osteoporotic humeri [4]. The 80% porosity stem had a single strut exceeding the fatigue strength when employed in the healthy bone.

The results of this study indicate that the more compliant nature of the porous stem geometries may allow for better load transmission through the proximal humeral bone, better matching the stress distributions of the intact bone and possibly mitigating stress-shielding effects. Importantly, this study also indicates that these porous stems have adequate strength for long-term use, as none were predicted to have catastrophic failure under the physiologically-relevant loads. Although these results are limited to a single boney geometry, it is based on the average shape of 75 shoulders and different bone densities are considered. Future work could leverage the shape model for probabilistic models that could explore the effect of stem porosity across a broader population. The development of these models are instrumental in determining if these structures are a viable solution to combatting orthopaedic implant infections.

Aim

Studies have shown that retention of antibiotic cement spacer in selected elderly patients with low functional demand represents a viable option for periprosthetic joint infections (PJI) treatment^1,2.

The aim of this study is to compare the efficacy in infection treating among modular taylored preformed and hand-made antibiotic spacers. Our hypothesis is that modular tailored preformed spacer provides a better rate of infection resolution, better radiological and functional outcomes compared to hand-made spacers.

Arthroscopic hip procedures have increased dramatically over the last decade as equipment and techniques have improved. Patients who require hip arthroscopy for femoroacetabular impingement on occasion require surgery on the contralateral hip. Previous studies have found that younger age of presentation and lower Charlson comorbidity index have higher risk for requiring surgery on the contralateral hip but have not found correlation to anatomic variables. The purpose of this study is to evaluate the factors that predispose a patient to requiring subsequent hip arthroscopy on the contralateral hip.

This is an IRB-approved, single surgeon retrospective cohort study from an academic, tertiary referral centre. A chart review was conducted on 310 primary hip arthroscopy procedures from 2009-2020. We identified 62 cases that went on to have a hip arthroscopy on the contralateral side. The bilateral hip arthroscopy cohort was compared to unilateral cohort for sex, age, BMI, pre-op alpha angle and centre edge angle measured on AP pelvis XRay, femoral torsion, traction time, skin to skin time, Tonnis grade, intra-op labral or chondral defect. A p-value <0.05 was deemed significant.

Of the 62 patients that required contralateral hip arthroscopy, the average age was 32.7 compared with 37.8 in the unilateral cohort (p = 0.01) and BMI was lower in the bilateral cohort (26.2) compared to the unilateral cohort (27.6) (p=0.04). The average alpha angle was 76.3⁰ in the bilateral compared to 66⁰ in the unilateral cohort (p = 0.01). Skin to skin time was longer in cases in which a contralateral surgery was performed (106.3 mins vs 86.4 mins) (p=0.01). Interestingly, 50 male patients required contralateral hip arthroscopy compared to 12 female patients (p=0.01). No other variables were statistically significant.

In conclusion, this study does re-enforce existing literature by stating that younger patients are more likely to require contralateral hip arthroscopy. This may be due to the fact that these patients require increased range of motion from the hip joint to perform activities such as sports where as older patients may not need the same amount of range of motion to perform their activities. Significantly higher alpha angles were noted in patients requiring contralateral hip arthroscopy, which has not been shown in previous literature. This helps to explain that larger CAM deformities will likely require contralateral hip arthroscopy because these patients likely impinge more during simple activities of daily living. Contralateral hip arthroscopy is also more common in male patients who typically have a larger CAM deformity. In summary, this study will help to risk stratify patients who will likely require contralateral hip arthroscopy and should be a discussion point during pre-operative counseling. That offering early subsequent or simultaneous hip arthroscopy in young male patients with large CAMs should be offered when symptoms are mild.

Degenerative disc disease (DDD) is a common cause of lower back pain. Calcification of the intervertebral disc (IVD) has been correlated with DDD, and is especially prevalent in scoliotic discs. The appearance of calcium deposits has been shown to increase with age, and its occurrence has been associated with several other disorders such as hyperparathyroidism, chondrocalcinosis, and arthritis. Trauma, vertebral fusion and infection have also been shown to increase the incidence of IVD calcification. Our data indicate that Ca²⁺ and expression of the extracellular calcium-sensing receptor (CaSR) are significantly increased in mild to severely degenerative human IVDs. In this study, we evaluated the effects of Ca²⁺ and CaSR on the degeneration and calcification of IVDs.

Human donor lumbar spines of Thompson grade 2, 3 and 4 through organ donations within 24 hs after death. IVD cells, NP and AF, were isolated from tissue by sequential digestion with Pronase followed by Collagenase. Cells were expanded for 7 days under standard cell culture conditions. Immunohistochemistry was performed on IVD tissue to validate the grade and expression of CaSR. Free calcium levels were also measured and compared between grades. Immunocytochemistry, Western blotting and RT-qPCR were performed on cultured NP and AF cells to demonstrate expression of CaSR, matrix proteins aggrecan and collagen, catabolic enzymes and calcification markers. IVD cells were cultured in increasing concentrations of Ca²⁺ [1.0-5.0 mM], CaSR allosteric agonist (cincalcet, 1 uM), and IL-1b [5 ng/mL] for 7 days. Ex vivo IVD organ cultures were prepared using PrimeGrowth Disc Isolation System (Wisent Bioproducts, Montreal, Quebec). IVDs were cultured in 1.0, 2.5 mM Ca²⁺ or with cinacalcet for 21 days to determine effects on disc degeneration, calcification and biomechanics. Complex modulus and structural stiffness of disc tissues was determined using the MACH-1 mechanical testing system (Biomomentum, Laval, Quebec).

Ca²⁺ dose-dependently decreased matrix protein synthesis of proteoglycan and Col II in NP and AF cells, similar to treatment with IL-1b. (n = 4). Contrarily to IL-1b, Ca²⁺ and cincalcet did not significantly increase the expression of catabolic enzymes save ADAMTS5. Similar effects were observed in whole organ cultures, as Ca²⁺ and cinacalcet decreased proteoglycan and collagen content. Although both Ca²⁺ and cinacalcet increased the expression of alkaline phosphatase (ALP), only in Ca²⁺-treated IVDs was there evidence of calcium deposits in NP and AF tissues as determined by von Kossa staining. Biomechanical studies on Ca²⁺ and cinacalcet-treated IVDs demonstrated decreases in complex modulus (p<0.01 and p<0.001, respectively; n=5), however, only Ca²⁺-treated IVDs was there significant increases stiffness in NP and AF tissues (p<0.001 and p<0.05, respectively; n=3).

Our results suggest that changes in the local concentrations of calcium and activation of CaSR affects matrix protein synthesis, calcification and IVD biomechanics. Ca²⁺ may be a contributing factor in IVD degeneration and calcification.

Hallux valgus surgery can result in moderate to severe post-operative pain requiring the use of narcotic medication. The percutaneous distal metatarsal osteotomy is a minimally invasive approach which offers many advantages including minimal scarring, immediate weight bearing and decreased post-operative pain. The goal of this study is to determine whether the use of narcotics can be eliminated using an approach combining multimodal analgesia, ankle block anesthesia and a minimally invasive surgical approach.

Following ethics board approval, a total of 160 ambulatory patients between the ages of 18-70 with BMI ≤ 40 undergoing percutaneous hallux valgus surgery are to be recruited and randomized into Narcotic-free (NF) or Standard (S) groups. To date, 72 patients have been recruited (38 NF and 34 S). The NF group received acetaminophen, naproxen, pregabalin 75mg and 100mg Ralivia (tramadol extended release) before surgery and acetaminophen, naproxen, pregabalin 150mg one dose and Ralivia 100mg BID for five days, as well as a rescue narcotic (hydromorphone, 1mg pills) after surgery. The S group received acetaminophen and naproxen prior to surgery and acetaminophen, naproxen and hydromorphone (1mg pills) post-operatively, our current standard. Visual analog scales (VAS) were used to assess pain and narcotic consumption was recorded at 6, 12, 24, 36, 48, 72 hours and seven days post-operatively. Patients wore a smart watch to record the number of daily steps and sleep hours. A two-sided t-test was used to compare the VAS scores and narcotic consumption.

During the first post-operative week, the NF group consumed in total an average of 6.5 pills while the S group consumed in total an average of 16 pills and this difference was statistically significant (p-value=0.001). Importantly, 19 patients (50%) in the NF group and four patients (12%) in the S group did not consume any narcotics post-operatively.

For the VAS scores at 24, 48, 72 hours and seven days the NF group's average scores were 2.17, 3.17, 2.92, 2.06 respectively and the S group's average scores were 3.97, 4.2, 3.23, 1.97. There was a statistically significant difference between the groups at 24 and 48hours (the NF group scored lower on the VAS) with a p-value of 0.0008 and 0.04 respectively, but this difference is not considered clinically significant as the minimal clinically important difference reported in the literature is a two-point differential. The NF group walked an average of 1985.75 steps/day and slept an average of 8h01 minute/night, while the S group walked an average of 1898.26 steps/day and slept an average of 8h26 minutes/night in the first post-operative week. Hallux valgus remains a common orthopedic foot problem for which surgical treatment results in moderate to severe post-operative pain. This study demonstrates that with the use of multimodal analgesia, ultrasound guided ankle blocks and a percutaneous surgical technique, narcotic requirements decreased post-operatively. The use of long-acting tramadol further decreased the need for narcotic consumption. Despite decreased use of narcotics, this combined novel approach to hallux valgus surgery allows for early mobilization and excellent pain control.

Aim

Vancomycin is frequently used for bone and joint infections (BJI) because of the main role of Gram-positive bacteria as potential causal agents. It is crucial to achieve optimal vancomycin plasma concentrations since the first day to maximize treatment clinical and microbiological efficacy. The aim was to describe the patients’ profile that are more likely to achieve an optimal pharmacokinetic/pharmacodynamics (PK/PD) vancomycin target in the first therapeutic drug monitoring (TDM) sample.

Since its creation, labral repair has become the preferred method among surgeons for the arthroscopic treatment of acetabular labral tears resulting in pain and dysfunction for patients. Labral reconstruction is performed mainly in revision hip arthroscopy but can be used in the primary setting when the labrum cannot be repaired or is calcified. The purpose of this study was to compare the survival between primary labral repair and labral reconstruction with survival defined as no further surgery (revision or total hip replacement).

Patients who underwent labral repair or reconstruction between January 2005 and December 2018 in the primary setting were included in the study. Patients were included if they had primary hip arthroscopy with the senior author for femoroacetabular impingement (FAI), involving either labral reconstruction or labral repair, and were within the ages of 18 and 65 at the time of surgery. Exclusion criteria included confounding injuries (Leggs Calves Perthes, avascular necrosis, femoral head fracture, etc.), history of unilateral or bilateral hip surgeries, or Tönnis grades of 2 or 3 at the time of surgery. Labral repairs were performed when adequate tissue was available for repair and labral reconstruction was performed when tissue was absent, ossified or torn beyond repair.

A total of 501 labral repairs and 114 labral reconstructions performed in the primary setting were included in the study. Labral reconstruction patients were older (37±10) compared to labral repair (34±11).(p=0.021). Second surgeries were required in 19/114 (17%) of labral reconstruction and 40/501(8%) [odds ratio: 2.3; 95% CI 1.3 to 4.2] (p=0.008). Revision hip arthroscopy were required in 6/114(5%) labral reconstructions and 33/501(6.5%) labral repair (p=0.496). Total hip replacement was required in 13/114 labral reconstructions and 7/501 labral repairs [odds ratio:9.1 95%CI 3.5 to 23] (p=< 0.01). The mean survival for the labral repair group was 10.2 years (95%CI:10 to 10.5) and 11.9 years (98%CI:10.9 to 12.8) in the labral reconstruction group.

Conversion to total hip was required more often following primary labral reconstruction. Revision hip arthroscopy rates were similar between groups as was the mean survival, with both over 10 years. Similar survival was seen in labral repair and reconstruction when strict patient selection criteria are followed.

Aim

The rise of multidrug-resistant bacteria and the decreasing efficacy of antibiotic therapy in successfully treating biofilm-associated infections are prompting the exploration of alternative treatment options. This study investigates the efficacy of different bioactive glass (BAG) formulations - alone or combined with vancomycin - to eradicate biofilm. Further, we study the influence of BAG on pH and osmotic pressure as important factors limiting bacterial growth.

In older patients (>75 years of age), with an intact rotator cuff, requiring a total shoulder replacement (TSR) there is, at present, uncertainty whether an anatomic TSR (aTSR) or a reverse TSR (rTSR) is best for the patient. This comparison study of same age patients aims to assess clinical and radiological outcomes of older patients (≥75 years) who received either an aTSR or a rTSA.

Consecutive patients with a minimum age of 75 years who received an aTSR (n=44) or rTSR (n=51) were prospectively studied. Pre- and postoperative clinical evaluations included the ASES score, Constant score, SPADI score, DASH score, range of motion (ROM) and pain and patient satisfaction for a follow-up of 2 years. Radiological assessment identified glenoid and humeral component osteolysis, including notching with a rTSR.

Postoperative improvement for ROM and all clinical assessment scores for both groups was found. There were significantly better patient reported outcome scores (PROMs) in the aTSR group compared with the rTSR patients (p<0.001). Both groups had only minor osteolysis on radiographs. No revisions were required in either group. The main complications were scapular stress fractures for the rTSR patients and acromioclavicular joint pain for both groups.

This study of older patients (>75 years) demonstrated that an aTSR for a judiciously selected patient with good rotator cuff muscles can lead to a better clinical outcome and less early complications than a rTSR.

Glenoid baseplate orientation in reverse shoulder arthroplasty (RSA) influences clinical outcomes, complications, and failure rates. Novel technologies have been produced to decrease performance heterogeneity of low and high-volume surgeons. This study aimed to determine novice and experienced shoulder surgeon's ability to accurately characterise glenoid component orientation in an intra-operative scenario.

Glenoid baseplates were implanted in eight fresh frozen cadavers by novice surgical trainees. Glenoid baseplate version, inclination, augment rotation, and superior-inferior centre of rotation (COR) offset were then measured using in-person visual assessments by novice and experienced shoulder surgeons immediately after implantation. Glenoid orientation parameters were then measured using 3D CT scans with digitally reconstructed radiographs (DRRs) by two independent observers. Bland-Altman plots were produced to determine the accuracy of glenoid orientation using standard intraoperative assessment compared to postoperative 3D CT scan results.

Visual assessment of glenoid baseplate orientation showed “poor” to “fair” correlation to 3D CT DRR measurements for both novice and experienced surgeon groups for all measured parameters. There was a clinically relevant, large discrepancy between intra-operative visual assessments and 3D CT DRR measurements for all parameters. Errors in visual assessment of up to 19.2 degrees of inclination and 8mm supero-inferior COR offset occurred. Experienced surgeons had greater measurement error than novices for all measured parameters.

Intra-operative measurement errors in glenoid placement may reach unacceptable clinical limits. Kinesthetic input during implantation likely improves orientation understanding and has implications for hands-on learning.

Primary hip and knee joint replacements in Canada have been estimated to cost over $1.4 billion dollars annually, with revision surgery costing $177 million. The most common cause of revision arthroplasty surgery in Canada is infection. Periprosthetic joint infections (PJIs) are a devastating though preventable complication following arthroplasty. Though variably used, antibiotic laden bone cement (ALBC) has been demonstrated to decrease PJIs following primary total knee arthroplasty (TKA). Unfortunately, ALBC is costlier than regular bone cement (RBC). Therefore, the aim of this study was to determine if the routine use of ALBC in primary TKA surgery is a cost-effective practice from the perspective of the Canadian healthcare system.

A decision tree was constructed using a decision analysis software (TreeAge Software, Williamstown, Massachusetts) to a two-year time horizon comparing primary TKA with either ALBC or RBC from the perspective of a single-payer healthcare system. All costs were in 2020 Canadian dollars. Health utilities were in the form of quality adjusted life years (QALYs). Model inputs for cost were derived from regional and national databases. Health utilities and probability parameters were derived from the latest literature. One-way deterministic sensitivity analysis was performed on all model parameters. The primary outcome of this analysis was an incremental cost-effectiveness ratio (ICER) with a willingness-to-pay (WTP) threshold of $50,000 per QALY.

Primary TKA with ALBC (TKA-ALBC) was found to be more cost-effective compared to primary TKA with RBC (TKA-RBC). More specifically, TKA-ALBC dominated TKA-RBC as it was less costly on the long term ($11,160 vs. $11,118), while providing the same QALY (1.66). The ICER of this cost-utility analysis (CUA) was $-11,049.72 per QALY, much less than the WTP threshold of $50,000 per QALY. The model was sensitive to costs of ALBC-TKA as well as the probability of PJI following ALBC-TKA and RBC-TKA. ALBC ceased to be cost effective once the cost of ALBC was greater than $223.08 CAD per bag of cement.

The routine use of ALBC in primary TKA is a cost-effective practice in the context of the Canadian healthcare system as long as the cost of ALBC is maintained at a reasonable price and the published studies to-date keep supporting the efficacy of ALBC in decreasing PJI following primary TKA. Further, this analysis is very conservative, and ALBC is likely much more cost-effective than presented. This is due to this model's revision surgery cost parameter being based on the average cost of all revision TKA surgery in Canada, regardless of etiology. Considering many PJIs require two-stage revisions, the cost parameter used in this analysis for revision surgery is an underestimate of true cost. Ultimately, this is the first cost-effectiveness study evaluating this topic from the perspective of the Canadian healthcare system and can inform future national guidelines on the subject matter.

Abstract

Abstract

The purpose of this prospective pilot study is to examine the feasibility of a physiotherapist led rapid access shoulder screening clinic (RASC). The goal of this study is to assess for improvements in patient access to care, patient reported outcome measures, patient reported experience measures, and cost outcomes using time driven activity based costing methods.

Patient recruitment began in January 2021. Consultation requests from general practitioners and emergency rooms are analyzed and triaged through a central system. One half of patients awaiting consultation were triaged to the traditional route used at our center while the other half were triaged to be assessed at the RASC. Outcome measures consisting of the Simple Shoulder Test and SF-12 were recorded at the initial consultation and at follow up appointments. Cost benefit analysis was conducted using time driven activity based costing methods (TD-ABC).

From January to August of 2021, 123 new patients were triaged for RASC assessment. On average, the RASC gets 10 new referrals per month. As of September 2021, there are 65 patients still on waitlist for RASC assessment with 58 having been assessed. Of the 58, 11% were discharged through the RASC, 48% pursued private physiotherapy, 14% had injections, 19% proceeded on for surgical consultation, and 8% did not show. Over time same time period, approximately 15 new patients were seen in consultation by the surgeon's office.

Thirty-five responses were obtained from RASC patients during their initial intake assessment. The average age of respondents was 54.7 with 21 females and 14 males. Median SF-12 scores in the physical dimension (PCS-12) for RASC patients were 36.82 and mental (MCS-12) 49.38927. Median Simple Shoulder Test scores measured 6. Of the patients who responded to the follow up questionnaires after completing physiotherapy at the RASC, both the SF-12 and Simple Shoulder Test scoring improved. Median PCS-12 measured 47.08, MCS-12 of 55.87, and Simple Shoulder Test measured 8.

RASC assessments by PT saved $172.91 per hour for consultation and $157.97 per hour for patient follow ups.

Utilization of a physiotherapy led rapid access shoulder clinic resulted in improvements in patient outcomes as measured by the SF-12 and Simple Shoulder Test as well as significant direct cost savings. Proper triage protocols to identify which patients would be suitable for RASC assessment, buy-in from physiotherapists, and timely assessment of patients for early initiation of rehabilitation for shoulder pain is paramount to the success of a RASC system at our centre. Future research direction would be geared to analyzing a larger dataset as it becomes available.

Aim

The aim of this study was to investigate the metabolomic profile of synovial fluid in periprosthetic joint infection (PJI) cases regarding a possible diagnostic approach. Also, further information about the metabolic composition of synovial fluid in PJI may point to future diagnostic and therapeutic approaches.

With the rising rates, and associated costs, of total knee arthroplasty (TKA), enhanced clarity regarding patient appropriateness for TKA is warranted. Towards addressing this gap, we elucidated in qualitative research that surgeons and osteoarthritis (OA) patients considered TKA need, readiness/willingness, health status, and expectations of TKA most important in determining patient appropriateness for TKA. The current study evaluated the predictive validity of pre-TKA measures of these appropriateness domains for attainment of a good TKA outcome.

This prospective cohort study recruited knee OA patients aged 30+ years referred for TKA at two hip/knee surgery centers in Alberta, Canada. Those receiving primary, unilateral TKA completed questionnaires pre-TKA assessing TKA need (WOMAC-pain, ICOAP-pain, NRS-pain, KOOS-physical function, Perceived Arthritis Coping Efficacy, prior OA treatment), TKA readiness/willingness (Patient Acceptable Symptom State (PASS), willingness to undergo TKA), health status (PHQ-8, BMI, MSK and non-MSK comorbidities), TKA expectations (HSS KR Expectations survey items) and contextual factors (e.g., age, gender, employment status). One-year post-TKA, we assessed for a ‘good outcome’ (yes/no), defined as improved knee symptoms (OARSI-OMERACT responder criteria) AND overall satisfaction with TKA results. Multiple logistic regression, stepwise variable selection, and best possible subsets regression was used to identify the model with the smallest number of independent variables and greatest discriminant validity for our outcome. Receiver Operating Characteristic (ROC) curves were generated to compare the discriminative ability of each appropriateness domain based on the ‘area under the ROC curve’ (AUC). Multivariable robust Poisson regression was used to assess the relationship of the variables to achievement of a good outcome.

f 1,275 TKA recipients, 1,053 (82.6%) had complete data for analyses (mean age 66.9 years [SD 8.8]; 58.6% female). Mean WOMAC pain and KOOS-PS scores were 11.5/20 (SD 3.5) and 52.8/100 (SD 17.1), respectively. 78.1% (95% CI 75.4–80.5%) achieved a good outcome. Stepwise variable selection identified optimal discrimination was achieved with 13 variables. The three best 13-variable models included measures of TKA need (WOMAC pain, KOOS-PS), readiness/willingness (PASS, TKA willingness), health status (PHQ-8, troublesome hips, contralateral knee, low back), TKA expectations (the importance of improved psychological well-being, ability to go up stairs, kneel, and participate in recreational activities as TKA outcomes), and patient age. Model discrimination was fair for TKA need (AUC 0.68, 95% CI 0.63-0.72), TKA readiness/willingness (AUC 0.61, 95% CI 0.57-0.65), health status (AUC 0.59, 95% CI 0.54-0.63) and TKA expectations (AUC 0.58, 95% CI 0.54-0.62), but the model with all appropriateness variables had good discrimination (AUC 0.72, 95% CI 0.685-0.76). The likelihood of achieving a good outcome was significantly higher for those with greater knee pain, disability, unacceptable knee symptoms, definite willingness to undergo TKA, less depression who considered improved ability to perform recreational activities or climb stairs ‘very important’ TKA outcomes, and lower in those who considered it important that TKA improve psychological wellbeing or ability to kneel.

Beyond surgical need (OA symptoms) and health status, assessment of patients’ readiness and willingness to undergo, and their expectations for, TKA, should be incorporated into assessment of patient appropriateness for surgery.

Thoracic hyperkyphosis (TH – Cobb angle >40°) is correlated with rotator cuff arthropathy and associated with anterior tilting and protraction of scapula, impacting the glenoid orientation and the surrounding musculature. Reverse total shoulder arthroplasty (RTSA) is a reliable surgical treatment for patients with rotator cuff arthropathy and recent literature suggests that patients with TH may have comparable range of motion after RTSA. However, there exists no study reporting the possible link between patient-reported outcomes, humeral retroversion and TH after RTSA. While the risk of post-operative complications such as instability, hardware loosening, scapular notching, and prosthetic infection are low, we hypothesize that it is critical to optimize the biomechanical parameters through proper implant positioning and understanding patient-specific scapular and thoracic anatomy to improve surgical outcomes in this subset of patients with TH.

Patients treated with primary RTSA at an academic hospital in 2018 were reviewed for a two-year follow-up. Exclusion criteria were as follows: no pre-existing chest radiographs for Cobb angle measurement, change in post-operative functional status as a result of trauma or medical comorbidities, and missing component placement and parameter information in the operative note. As most patients did not have a pre-operative chest radiograph, only seven patients with a Cobb angle equal to or greater than 40° were eligible. Chart reviews were completed to determine indications for RTSA, hardware positioning parameters such as inferior tilting, humeral stem retroversion, glenosphere size/location, and baseplate size. Clinical data following surgery included review of radiographs and complications. Follow-up in all patients were to a period of two years. The American Shoulder and Elbow Surgeons (ASES) Shoulder Score was used for patient-reported functional and pain outcomes.

The average age of the patients at the time of RTSA was 71 years old, with six female patients and one male patient. The indication for RTSA was primarily rotator cuff arthropathy. Possible correlation between Cobb angle and humeral retroversion was noted, whereby, Cobb angle greater than 40° matched with humeral retroversion greater than 30°, and resulted in significantly higher ASES scores. Two patients with mean Cobb angle of 50° and mean humeral retroversion 37.5° had mean ASES scores of 92.5. Five patients who received mean humeral retroversion of 30° had mean lower ASES scores of 63.7 (p < 0 .05). There was no significant correlation with glenosphere size or position, baseplate size, degree of inferior tilting or lateralization.

Patient-reported outcomes have not been reported in RTSA patients with TH. In this case series, we observed that humeral stem retroversion greater than 30° may be correlated with less post-operative pain and greater patient satisfaction in patients with TH. Further clinical studies are needed to understanding the biomechanical relationship between RTSA, humeral retroversion and TH to optimize patient outcomes.

Postoperative surgical site infection in patients treated with lumbosacral fusion has been believed to be caused by perioperative contamination (Perioperative Inside-Out infections) in patients with comorbidities. With the proximity of these incisions to the perianal region and limited patient mobility in the early post-operative period, local contamination from gastrointestinal and/or urogenital flora (Postoperative Outside-In infections) should be considered as a major source of complication.

A single center, retrospective review of adult patients treated with open posterior lumbosacral fusions between January 2014 and January 2021. We aimed to identify common factors in patients experiencing deep postoperative infections. Oncological, minimally invasive, primary infection, and index procedures carried out at other institutions were excluded.

We identified 489 eligible patients, 20 of which required debridement deep to the fascia (4.1%). Mean age (62.9 vs 60.8), operative time (420 vs 390 minutes), estimated blood loss (1772 vs 1790 mL) and median levels fused (8.5 vs 9) were similar between the infected and non-infected groups. There was a higher percentage of deformity patients (75% vs 29%) and increased BMI (32.7 vs 28.4) in the infected group. The mean time from primary procedure to debridement was 40.8 days. Four patients showed no growth on culture. Three showed Staphylococcus species (Perioperative Inside-Out infections) requiring debridement at a mean of 100.3 days (95%CI 0- 225 days). Thirteen patients showed infection with intestinal or urogenital pathogens (Postoperative Outside-In infections) requiring debridement at a mean of 20.0 days (95%CI 9-31 days). Postoperative Outside-In infections led to debridement 80.3 days earlier than Perioperative Inside-Out infections (p= 0.007).

In this series, 65% of deep infections were due to early local contamination by gastrointestinal and/or urogenital tracts pathogens. These infections were debrided significantly earlier than the Staphylococcus species infections. Due to the proximity of the incisions to the perianal region, there should be increased focus on post-operative local wound management to ensure these pathogens are away from the wound during the critical stages of wound healing.

Abstract

Abstract:

Abstract

Aim

Acute hematogenous periprosthetic joint infection (AHI) is a diagnosis on the rise. The management is challenging and the optimum treatment is not clearly defined. The purpose of this study was to evaluate the characteristics of AHI, and to study risk factors affecting treatment outcome.

One in five patients remain unsatisfied due to ongoing pain and impaired mobility following total knee arthroplasty (TKA). It is important if surgeons can pre-operatively identify which patients may be at risk for poor outcomes after TKA. The purpose of this study was to determine if there is an association between pre-operative measures and post-operative outcomes in patients who underwent TKA.

This study included 28 patients (female = 12 / male = 16, age = 63.6 ± 6.9, BMI = 29.9 ± 7.4 kg/m2) with knee osteoarthritis who were scheduled to undergo TKA. All surgeries were performed by the same surgeon (GD), and a subvastus approach was performed for all patients. Patients visited the gait lab within one-month of surgery and 12 months following surgery. At the gait lab, patients completed the knee injury and osteoarthritis outcome score (KOOS), a timed up and go (TUG), and walking task. Variables of interest included the five KOOS sub-scores (symptoms, pain, activities of daily living, sport & recreation, and quality of life), completion time for the TUG, walking speed, and peak knee biomechanics variables (flexion angle, abduction moment, power absorption). A Pearson's product-moment correlation was run to assess the relationship between pre-operative measures and post-operative outcomes in the TKA patients.

Preliminary analyses showed the relationship to be linear with all variables normally distributed, as assessed by Shapiro-Wilk's test (p > .05), and there were no outliers. There were no statistically significant correlations between any of the pre-operative KOOS sub-scores and any of the post-operative biomechanical outcomes. Pre-operative TUG time had a statistically significant, moderate positive correlation with post-operative peak knee abduction moments [r(14) = .597, p < .001] and peak knee power absorption [r(14) = .498, p = .007], with pre-operative TUG time explaining 36% of the variability in peak knee abduction moment and 25% of the variability in peak knee power absorption. Pre-operative walking speed had a statistically significant, moderate negative correlation with post-operative peak knee abduction moments [r(14) = -.558, p = .002] and peak knee power absorption [r(14) = -.548, p = .003], with pre-operative walking speed explaining 31% of the variability in peak knee abduction moment and 30% of the variability in peak knee power absorption.

Patient reported outcome measures (PROMs), such as the KOOS, do indicate the TKA is generally successful at relieving pain and show an overall improvement. However, their pre-operative values do not correlate with any biomechanical indicators of post-operative success, such as peak knee abduction moment and knee power. Shorter pre-operative TUG times and faster pre-operative walking speeds were correlated with improved post-operative biomechanical outcomes. These are simple tasks surgeons can implement into their clinics to evaluate their patients. Future research should expand these findings to a larger sample size and to determine if other factors, such as surgical approach or implant design, improves patient outcomes.

Aims

Despite numerous studies on periprosthetic joint infections (PJI), there are no robust data on the risk factors and timing of metachronous infections. This study was performed to answer the following questions: 1) Is there any difference of manifestation time of metachronous PJIs between different localizations of multiple artificial joints? 2) Can we identify any specific risk factor for metachronous PJIs for different localizations of multiple artificial joints?

A concern of metal on metal hip resurfacing arthroplasty is long term exposure to Cobalt (Co) and Chromium (CR) wear debris from the bearing. This study compares whole blood metal ion levels from patients drawn at one-year following Birmingham Hip Resurfacing (BHR) to levels taken at a minimum 10-year follow-up.

A retrospective chart review was conducted to identify all patients who underwent a BHR for osteoarthritis with a minimum 10-year follow-up. Whole blood metal ion levels were drawn at final follow-up in June 2019. These results were compared to values from patients with one-year metal ion levels.

Of the 211 patients who received a BHR, 71 patients (54 males and 17 females) had long term metal ion levels assessed (mean follow-up 12.7 +/− 1.4 years). The mean Co and Cr levels for patients with unilateral BHRs (43 males and 13 females) were 3.12 ± 6.31 ug/L and 2.62 ± 2.69 ug/L, respectively, and 2.78 ± 1.02 ug/L and 1.83 ± 0.65 ug/L for patients with bilateral BHRs (11 males and 4 females). Thirty-five patients (27 male and 8 female) had metal-ion levels tested at one-year postoperatively. The mean changes in Co and Cr levels were 2.29 ug/l (p = 0.0919) and 0.57 (p = 0.1612), respectively, at one year compared to long-term. These changes were not statistically significant.

This study reveals that whole blood metal ion levels do not change significantly when comparing one-year and ten-year Co and Cr levels. These ion levels appear to reach a steady state at one year.

Our results also suggest that regular metal-ion testing as per current Medicines and Healthcare products Regulatory Agency (MHRA) guidelines may be impractical for asymptomatic patients. Metal-ion levels, in and of themselves, may in fact possess little utility in determining the risk of failure and should be paired with radiographic and clinical findings to determine the need for revision.

Aim

To evaluate the efficiency of pulse lavage combined with electrical fields to remove biofilm from a metallic surface.

Aim

Synovial fluid D-lactate may be useful for diagnosing septic arthritis (SA) as this biomarker is almost exclusively produced by bacteria. We evaluated the performance of synovial fluid D-lactate and determined its optimal cut-off value for diagnosing SA.

Background

Surgical site infection following spine surgery is associated with increased morbidity, mortality and increased cost for the health care system. The reported pooled incidence is 3%. Perioperative antibiotic prophylaxis is a key factor in lowering the risk of acquiring an infection. Previous studies have assessed perioperative cefuroxime concentrations in the anterior column of the cervical spine with an anterior surgical approach. However, the majority of surgeries are performed in the posterior column and often involve the lumbar spine. Accordingly, the objective was to compare the perioperative tissue concentrations of cefuroxime in the anterior and posterior column of the same lumbar vertebra using microdialysis in an experimental porcine model.

Immigrated Canadians make up approximately 20% of the total population in Canada, and 30% of the population in Ontario. Despite universal health coverage and an equal prevalence of severe arthritis in immigrants relative to non-immigrants, the former may be underrepresented amongst arthroplasty recipients secondary to challenges navigating the healthcare system. The primary aim of this study was to determine if utilization of arthroplasty differs between immigrant populations and persons born in Canada. The secondary aim was to determine differences in outcomes following total hip and knee arthroplasty (THA and TKA, respectively).

This is a retrospective population-based cohort study using health administrative databases. All patients aged ≥18 in Ontario who underwent their first primary elective THA or TKA between 2002 and 2016 were identified. Immigration status for each patient was identified via linkage to the ‘Immigration, Refugee and Citizenship Canada’ database. Outcomes included all-cause and septic revision surgery within 12-months, dislocation (for THA) and total post-operative case cost and were compared between groups. Cochrane-Armitage Test for Trend was utilized to determine if the uptake of arthroplasty by immigrants changed over time.

There was a total of 186,528 TKA recipients and 116,472 THA recipients identified over the study period. Of these, 10,193 (5.5%) and 3,165 (2.7%) were immigrants, respectively. The largest proportion of immigrants were from the Asia and Pacific region for those undergoing TKA (54.0%) and Europe for THA recipients (53.4%). There was no difference in the rate of all-cause revision or septic revision at 12 months between groups undergoing TKA (p=0.864, p=0.585) or THA (p=0.527, p=0.397), respectively. There was also no difference in the rate of dislocations between immigrants and people born in Canada (p=0.765, respectively).

Despite having similar complication rates and costs, immigrants represent a significantly smaller proportion of joint replacement recipients than they represent in the general population in Ontario. These results suggest significant underutilization of surgical management for arthritis among Canada's immigrant populations. Initiatives to improve access to total joint arthroplasty are warranted.

Over 500 supracondylar humerus fractures (SCHF) are treated at our institution each year. Our standard post-operative pathway includes a 3-week visit for splint removal, wire removal, and radiographs. Subsequent follow-up occurs at 12 weeks for a clinical examination. In an effort to minimize unnecessary follow-up visits, we investigated whether photographs and/or patient-reported outcome measure (PROM) scores could identify patients who do not need routine 3-month in-person follow-up.

At the 3-month visit, 248 SCHF patients (mean 6.2 yrs; 0.75-11yrs) had bilateral elbow motion (ROM) and carrying angles measured; and photographs documenting frontal and sagittal alignment of both injured and uninjured upper extremities, in both maximum elbow flexion and extension. Two independent assessors made the same measurements off the clinical photographs to compare these with the clinical measurements. Two PROMs: Self-Assessment Questionnaire (SAQ: 0 best to 14 worst) and QuickDASH (0 best to 100 worst) were completed at the 3-month visit.

Inter-rater reliability of the photograph measurements was excellent (Kappa: 0.88-0.93), but weakly concordant with clinical measurements (carrying angle Kappa=0.51;max flexion Kappa=0.68;max extension Kappa=0.64). SAQ moderately correlated with QuickDASH (Kappa=0.59) and performed better at identifying patients with abnormalities. SAQ score ≥ 4 identified patients meeting 3-month follow-up criteria, with sensitivity: 36.1%; specificity: 96.8% and negative-predictive-value (NPV): 87%.

We did not find that photographs were reliable. Although SAQ-score has high NPV, a more sensitive fracture-specific PROM is needed to identify patients who do not need a 3-month follow-up visit.

In multilevel posterior cervical instrumented fusions, extending the fusion across the cervico-thoracic junction at T1 or T2 (CTJ) has been associated with decreased rate of re-operation and pseudarthrosis but with longer surgical time and increased blood loss. The impact on patient reported outcomes (PROs) remains unclear. The primary objective was to determine whether extending the fusion through the CTJ influenced PROs at 3 and 12 months after surgery. Secondary objectives were to compare the number of patients reaching the minimally clinically important difference (MCID) for the PROs and mJOA, operative time duration, intra-operative blood loss (IOBL), length of stay (LOS), discharge disposition, adverse events (AEs), re-operation within 12 months of the surgery, and patient satisfaction.

This is a retrospective analysis of prospectively collected data from a multicenter observational cohort study of patients with degenerative cervical myelopathy. Patients who underwent a posterior instrumented fusion of 4 levels of greater (between C2-T2) between January 2015 and October 2020 with 12 months follow-up were included. PROS (NDI, EQ5D, SF-12 PCS and MCS, NRS arm and neck pain) and mJOA were compared using ANCOVA, adjusted for baseline differences. Patient demographics, comorbidities and surgical details were abstracted. Percentafe of patient reaching MCID for these outcomes was compared using chi-square test. Operative duration, IOBL, AEs, re-operation, discharge disposittion, LOS and satisfaction were compared using chi-square test for categorical variables and independent samples t-tests for continuous variables.

A total of 206 patients were included in this study (105 patients not crossing the CTJ and 101 crossing the CTJ). Patients who underwent a construct extending through the CTJ were more likely to be female and had worse baseline EQ5D and NDI scores (p> 0.05). When adjusted for baseline difference, there was no statistically significant difference between the two groups for the PROs and mJOA at 3 and 12 months. Surgical duration was longer (p 0.05). Satisfaction with the surgery was high in both groups but significantly different at 12 months (80% versus 72%, p= 0.042 for the group not crossing the CTJ and the group crossing the CTJ, respectively). The percentage of patients reaching MCID for the NDI score was 55% in the non-crossing group versus 69% in the group extending through the CTJ (p= 0.06).

Up to 12 months after the surgery, there was no statistically significant differences in PROs between posterior construct extended to or not extended to the upper thoracic spine. The adverse event profile did not differ significantly, but longer surgical time and blood loss were associated with construct extending across the CTJ.

Aim

Aim of this monocentric, prospective study was to evaluate the safety, efficacy, clinical and radiographical results at 24-month follow-up (N = 6 patients) undergoing hip revision surgery with severe acetabular bone defects (Paprosky 2C-3A-3B) using a combination of a novel phase-pure betatricalciumphosphate - collagen 3D matrix with allograft bone chips.

Abstract

Aim

This study investigated if co-administration of rifampicin with moxifloxacin led to a decrease in moxifloxacin concentrations in relevant tissues in a porcine model of implant-associated osteomyelitis caused S. aureus. Pharmacokinetics were measured using microdialysis and treatment effect was measured by quantifying bacterial load from implant and periprosthetic bone following a 1-stage revision and antibiotics.

En bloc resection for primary bone tumours and isolated metastasis are complex surgeries associated with a high rate of adverse events (AEs). The primary objective of this study was to explore the relationship between frailty/sarcopenia and major perioperative AEs following en bloc resection for primary bone tumours or isolated metastases of the spine. Secondary objectives were to report the prevalence and distribution of frailty and sarcopenia, and determine the relationship between these factors and length of stay (LOS), unplanned reoperation, and 1-year postoperative mortality in this population.

This is a retrospective study of prospectively collected data from a single quaternary care referral center consisting of patients undergoing an elective en bloc resection for a primary bone tumour or an isolated spinal metastasis between January 1st, 2009 and February 28th, 2020. Frailty was calculated with the modified frailty index (mFI) and spine tumour frailty index (STFI). Sarcopenia, determined by the total psoas area (TPA) vertebral body (VB) ratio (TPA/VB), was measured at L3 and L4. Regression analysis produced ORs, IRRs, and HRs that quantified the association between frailty/sarcopenia and major perioperative AEs, LOS, unplanned reoperation and 1-year postoperative mortality.

One hundred twelve patients met the inclusion criteria. Using the mFI, five patients (5%) were frail (mFI ³ 0.21), while the STFI identified 21 patients (19%) as frail (STFI ³ 2). The mean CT ratios were 1.45 (SD 0.05) and 1.81 (SD 0.06) at L3 and L4 respectively. Unadjusted analysis demonstrated that sarcopenia and frailty were not significant predictors of major perioperative AEs, LOS or unplanned reoperation. Sarcopenia defined by the CT L3 TPA/VB and CT L4 TPA/VB ratios significantly predicted 1-year mortality (HR of 0.32 per one unit increase, 95% CI 0.11-0.93, p=0.04 vs. HR of 0.28 per one unit increase, 95% CI 0.11-0.69, p=0.01) following unadjusted analysis. Frailty defined by an STFI score ≥ 2 predicted 1-year postoperative mortality (OR of 2.10, 95% CI 1.02-4.30, p=0.04).

The mFI was not predictive of any clinical outcome in patients undergoing en bloc resection for primary bone tumours or isolated metastases of the spine. Sarcopenia defined by the CT L3 TPA/VB and L4 TPA/VB and frailty assessed with the STFI predicted 1-year postoperative mortality on univariate analysis but not major perioperative AEs, LOS or reoperation. Further investigation with a larger cohort is needed to identify the optimal measure for assessing frailty and sarcopenia in this spine population.

Background

Bacteriophages are natural viruses of interest in the field of PJI. A paper previously reported the PhagoDAIR procedure (use of phages during DAIR) in three patients with PJI for whom explantation was not desirable. As the need to isolate the pathogen before surgery to perform phage susceptibility testing is a strong hindrance for the development of this procedure, we developed post-operative phage injections using ultrasound, in patients infected with S. aureus and/or P. aeruginosa who were eligible for the PhagoDAIR procedure, but for whom phages were not available at the time of surgery.

Abstract

The study of spinopelvic anatomy and movement has received great interest as these characteristics influence the biomechanical behavior (and outcome) following hip arthroplasty. However, to-date there is little knowledge of what “normal” is and how this varies with age. This study aims to determine how dynamic spino-pelvic characteristics change with age, with well-functioning hips and assess how these changes are influenced by the presence of hip arthritis.

This is an IRB-approved, cross-sectional, cohort study; 100 volunteers (asymptomatic hips, Oxford-Hip-sore>45) [age:53 ± 17 (24-87) years-old; 51% female; BMI: 28 ± 5] and 200 patients with end-stage hip arthritis [age:56 ± 19 (16-89) years-old; 55% female; BMI:28 ± 5] were studied. All participants underwent lateral spino-pelvic radiographs in the standing and deep-seated positions to determine maximum hip and spine flexion. Parameters measured included lumbar-lordosis (LL), pelvic incidence, pelvic-tilt (PT), pelvic-femoral angles (PFA). Lumbar flexion (ΔLL), hip flexion (ΔPFA) and pelvic movement (ΔPT) were calculated. The prevalence of spinopelvic imbalance (PI–LL>10?) was determined.

There were no differences in any of the spino-pelvic characteristics or movements between sexes. With advancing age, standing LL reduced and standing PT increased (no differences between groups). With advancing age, both hip (4%/decade) and lumbar (8%/decade) flexion reduced (p<0.001) (no difference between groups). ΔLL did not correlate with ΔPFA (rho=0.1). Hip arthritis was associated with a significantly reduced hip flexion (82 ±;22? vs. 90 ± 17?; p=0.003) and pelvic movements (1 ± 16? vs. 8 ± 16?; p=0.002) at all ages and increased prevalence of spinopelvic imbalance (OR:2.6; 95%CI: 1.2-5.7).

With aging, the lumbar spine loses its lumbar lordosis and flexion to a greater extent that then the hip and resultantly, the hip's relative contribution to the overall sagittal movement increases. With hip arthritis, the reduced hip flexion and the necessary compensatory increased pelvic movement is a likely contributor to the development of hip-spine syndrome and of spino-pelvic imbalance.

Aim

Diagnosing periprosthetic joint infections (PJI) can be very challenging, especially infections caused by low virulence microorganisms. No single test with a 100% accuracy is available yet. Hence, different infection definitions were introduced to improve the diagnostic confidence and quality of research articles. Due to constant developments in this field, infection definitions are adopted continuously. The aim of our study was to find the most sensitive currently available infection definition among three currently used criteria (International Consensus Meeting – criteria 2018 (ICM), Infectious Diseases Society of America - criteria 2013 (IDSA), and European Bone and Joint Infection Society – criteria 2021 (EBJIS)) for the diagnosis of PJI.

Periprosthetic joint infection (PJI) occurs in 0.2-2% of primary hip and knee arthroplasty and is a leading cause of revision surgery, impaired function, and increased morbidity and mortality. Topical, intrawound vancomycin administration allows for high local drug concentrations at the surgical site and has demonstrated good results in prevention of surgical site infection after spinal surgery. It is a promising treatment to prevent infection following hip and knee arthroplasty. Prior studies have been limited by small sample sizes and the low incidence of PJI. This systematic review and meta-analysis was performed to determine the effectiveness of topical vancomycin for the primary prevention of PJI in hip and knee arthroplasty.

A search of Embase, MEDLINE, and PubMed databases as of June 2020 was performed according to PRISMA guidelines. Studies comparing topical vancomycin to standard perioperative intravenous antibiotics in primary THA and TKA with a minimum of three months follow-up were identified. The results from applicable studies were meta-analysed to determine the impact of topical vancomycin on PJI rates as well as wound-related and overall complications. Results were expressed as odds ratios (ORs) and 95% confidence intervals

Nine comparative observational studies were eligible for inclusion. 3371 patients treated with 0.5-2g of topical vancomycin were compared to 2884 patients treated with standard care. Only one of nine studies found a significantly lower rate of PJI after primary THA or TKA (OR 0.09-1.97, p=0.04 for one study, p>0.05 for eight of nine studies), though meta-analysis showed a significant benefit, with vancomycin lowering PJI rates from 1.6% in controls to 0.7% in the experimental group (OR 0.47, p=0.02, Figure 1). Individually, only one of five studies showed a significant benefit to topical vancomycin in THA, while none of seven studies investigating PJI after TKA showed a benefit to topical vancomycin. In meta-analysis of our subgroups, there was a significant reduction in PJI with vancomycin in THA (OR 0.34, p=0.04), but there was no significant difference in PJI after TKA (OR 0.60, p = 0.13). In six studies which reported complication rates other than PJI, there were no significant differences in overall complication rates with vancomycin administration for any study individually (OR 0.48-0.94, p>0.05 for all studies), but meta-analysis found a significant difference in complications, with a 6.7% overall complication rate in controls compared to 4.8% after topical vancomycin, largely driven by a lower PJI incidence (OR 0.76, p=0.04).

Topical vancomycin is protective against PJI after hip and knee arthroplasty. No increase in wound-related or overall complication rates was found with topical vancomycin. This meta-analysis is the largest to date and includes multiple recent comparative studies while excluding other confounding interventions (such as povidone-iodine irrigation). However, included studies were predominantly retrospective and no randomized-controlled trials have been published. The limited evidence summarized here indicates topical vancomycin may be a promising modality to decrease PJI, but there is insufficient evidence to conclusively show a decrease in PJI or to demonstrate safety. A prospective, randomized-controlled trial is ongoing to better answer this question.

For any figures or tables, please contact the authors directly.

Adequate visual clarity is paramount to performing arthroscopic shoulder surgery safely, efficiently, and effectively. The addition of epinephrine in irrigation fluid, and the intravenous or local administration of tranexamic acid (TXA) have independently been reported to decrease bleeding thereby improving the surgeon's visualization during arthroscopic shoulder procedures. No study has compared the effect of systemic administered TXA, epinephrine added in the irrigation fluid or the combination of both TXA and epinephrine on visual clarity during shoulder arthroscopy with a placebo group. The purpose of this study is to determine if intravenous TXA is a safe alternative to epinephrine delivered by a pressure-controlled pump in improving arthroscopic shoulder visualization during arthroscopic procedures and whether using both TXA and epinephrine together has an additive effect in improving visualization.

The design of the study was a double-blinded, randomized controlled trial with four 1:1:1:1 parallel groups conducted at one center. Patients aged ≥18 years undergoing arthroscopic shoulder procedures including rotator cuff repair, arthroscopic biceps tenotomy/tenodesis, distal clavicle excision, subacromial decompression and labral repair by five fellowship-trained upper extremity surgeons were randomized into one of four arms: Pressure pump-controlled regular saline irrigation fluid (control), epinephrine (1ml of 1:1000) mixed in irrigation fluid (EPI), 1g intravenous TXA (TXA), and epinephrine and TXA (EPI/TXA). Visualization was rated on a 4-point Likert scale every 15 minutes with 0 indicating ‘poor’ quality and 3 indicating ‘excellent’ quality. The primary outcome measure was the unweighted mean of these ratings. Secondary outcomes included mean arterial blood pressure (MAP), surgery duration, surgery complexity, and adverse events within the first postoperative week.

One hundred and twenty-eight participants with a mean age (± SD) of 56 (± 11) years were randomized. Mean visualization quality for the control, TXA, EPI, and EPI/TXA groups were 2.1 (±0.40), 2.1 (±0.52), 2.6 (±0.37), 2.6 (±0.35), respectively. In a regression model with visual quality as the dependent variable, the presence/absence of EPI was the most significant predictor of visualization quality (R=0.525; p < 0 .001). TXA presence/absence had no effect, and there was no interaction between TXA and EPI. The addition of MAP and surgery duration strengthened the model (R=0.529; p < 0 .001). Increased MAP and surgery duration were both associated with decreased visualization quality. When surgery duration was controlled, surgery complexity was not a significant predictor of visualization quality. No adverse events were recorded in any of the groups.

Intravenous administration of TXA is not an effective alternative to epinephrine in the irrigation fluid to improve visualization during routine arthroscopic shoulder surgeries although its application is safe. There is no additional improvement in visualization when TXA is used in combination with epinephrine beyond the effect of epinephrine alone.

Abstract

Aim

A novel anti-infective biopolymer implant coating was developed to prevent bacterial biofilm formation and allow on-demand burst release of anti-infective silver (Ag) into the surrounding of the implant at any time after surgery via focused high-energy extracorporeal shock waves (fhESW).

To date, the literature has not yet revealed superiority of Minimally Invasive (MI) approaches over conventional techniques. We performed a systematic review to determine whether minimally invasive approaches are superior to conventional approaches in total hip arthroplasty for (1) clinical and (2) functional outcomes. We performed a meta-analysis of level 1 evidence to determine whether (3) minimally invasive approaches are superior to conventional approaches for clinical outcomes.

All studies comparing MI approaches to conventional approaches were eligible for analysis. The PRISMA guidelines were adhered to throughout this study. Registries were searched using the following MeSH terms: ‘minimally invasive’, ‘muscle-sparing’, ‘THA’, ‘THR’, ‘hip arthroplasty’ and ‘hip replacement’. Locations searched included PubMed, the Cochrane Library, ClinicalTrials.gov, the EU clinical trials register and the International Clinical Trials Registry Platform (World Health Organisation).

Twenty studies were identified. There were 1,282 MI THAs and 1,351 conventional THAs performed.

Intermuscular MI approaches are equivalent to conventional THA approaches when considering all-cause revision, aseptic revision, infection, dislocation, fracture rates and functional outcomes. Meta-analysis of level 1 evidence supports this claim.

Abstract

Abstract

Aim

Patients with late acute periprosthetic joint infections (PJI) and treated with surgical debridement have a high failure rate. Previous studies have shown that rheumatoid arthritis (RA) is an independent risk factor for treatment failure. We conducted a case-control study to identify predictors for failure in late acute PJI treatment in RA patients. We hypothesize that patients with RA have a higher failure rate compared to controls due to the use of immunosuppressive drugs.

Abstract

Abstract

Lumbar fusion surgery is an established procedure for the treatment of several spinal pathologies. Despite numerous techniques and existing devices, common surgical trends in lumbar fusion surgery are scarcely investigated. The purpose of this Canada-based study was to provide a descriptive portrait of current surgeons’ practice and implant preferences in lumbar fusion surgery while comparing findings to similar investigations performed in the United Kingdom.

Canadian Spine Society (CSS) members were sampled using an online questionnaire which was based on previous investigations performed in the United Kingdom. Fifteen questions addressed the various aspects of surgeons’ practice: fusion techniques, implant preferences, and bone grafting procedures. Responses were analyzed by means of descriptive statistics.

Of 139 eligible CSS members, 41 spinal surgeons completed the survey (29.5%). The most common fusion approach was via transforaminal lumber interbody fusion (TLIF) with 87.8% performing at least one procedure in the previous year. In keeping with this, 24 surgeons (58.5%) had performed 11 to 50 cases in that time frame. Eighty-six percent had performed no lumbar artificial disc replacements over their last year of practice. There was clear consistency on the relevance of a patient specific management (73.2%) on the preferred fusion approach. The most preferred method was pedicle screw fixation (78%). The use of stand-alone cages was not supported by any respondents. With regards to the cage material, titanium cages were the most used (41.5%). Published clinical outcome data was the most important variable in dictating implant choice (87.8%). Cage thickness was considered the most important aspect of cage geometry and hyperlordotic cages were preferred at the lower lumbar levels. Autograft bone graft was most commonly preferred (61.0%). Amongst the synthetic options, DBX/DBM graft (64.1%) in injectable paste form (47.5%) was preferred.

In conclusion, findings from this study are in partial agreement with previous work from the United Kingdom, but highlight the variance of practice within Canada and the need for large-scale clinical studies aimed to set specific guidelines for certain pathologies or patient categories.

A larger radial tuberosity, and therefore a smaller radioulnar space, may cause mechanical impingement of the DBT predisposing to tear. We sought to investigate anatomic factors associated with partial DBT tears by retrospectively reviewing 3-T MRI scans of elbows with partial DBT tears and a normal elbow comparison group

3-T MRI scans of elbows with partial DBT tears and elbows with no known pathology were reviewed retrospectively by two independent observers. Basic demographic data were collected and measurements of radial tuberosity length, radial tuberosity thickness, radio-ulnar space, and radial tuberosity-ulnar space were made using simultaneous tracker lines and a standardised technique. The presence or absence of enthesophytes and the presence of a single or double DBT were noted.

26 3-T MRI scans of 26 elbows with partial DBT tears and 30 3-T MRI scans of 30 elbows without pathology were included. Basic demographic data was comparable between the two groups. The tear group showed statistically significant larger mean measurements for radial tuberosity length (24.3mm vs 21.3mm, p=0.002), and radial tuberosity thickness (5.5mm vs 3.7mm, p=<0.0001. The tear group also showed statistically significant smaller measurements for radio-ulnar space (8.2mm vs 10.0mm, p=0.010), and radial tuberosity-ulnar space (7.2mm vs 9.1mm, p=0.013). There was a statistically significant positive correlation between partial DBT tears and presence of enthesophytes (p=0.007) as well as between partial DBT tears and having two discrete DBTs rather than a single or interdigitating tendon (p=<0.0001).

Larger radial tuberosities, and smaller radio-ulnar and radial tuberosity-ulnar spaces are associated with partial DBT tears. This may be due to chronic impingement, tendon delamination and consequent weakness which ultimately leads to tears. Enthesophytes may be associated with tears for the same reason. Having two discrete DBTs that do not interdigitate prior to insertion is also associated with partial tears.

Abstract Background

The treatment of bone and joint infections (BJI) involving multi-drug resistant bacteria remains a challenge. MDR Staphylococcus epidermidis (MDRSE) clones, resistant to methicillin, clindamycin, levofloxacin, rifampicin and even linezolid, have been reported worldwide. The interest of delafloxacin (DFX), theoretically active on MRSA, remains to be evaluated with respect to MDRSE.

Aim

The objective of this systematic review is to evaluate the current evidence for or against this up-and-coming treatment modality.

Restoration a joint's articular surface following degenerative or traumatic pathology to the osteochondral unit pose a significant challenge. Recent advances have shown the utility of collagen-based scaffolds in the regeneration of osteochondral tissue. To provide these collagen scaffolds with the appropriate superstructure novel techniques in 3D printing have been investigated. This study investigates the use of polyɛ-caprolactone (PCL) collagen scaffolds in a porcine cadaveric model to establish the stability of the biomaterial once implanted.

This study was performed in a porcine cadaveric knee model. 8mm defects were created in the medial femoral trochlea and repaired with a PCL collagen scaffold. Scaffolds were secured by one of three designs; Press Fit (PF), Press Fit with Rings (PFR), Press Fit with Fibrin Glue (PFFG). Mobilisation was simulated by mounting the pig legs on a continuous passive motion (CPM) machine for either 50 or 500 cycles. Biomechanical tensile testing was performed to examine the force required to displace the scaffold.

18 legs were used (6 PF, 6 PFR, 6 PFFG). Fixation remained intact in 17 of the cohort (94%). None of the PF or PFFG scaffolds displaced after CPM cycling. Mean peak forces required to displace the scaffold were highest in the PFFG group (3.173 Newtons, Standard deviation = 1.392N). The lowest peak forces were observed in the PFR group (0.871N, SD = 0.412N), while mean peak force observed in the PF group was 2.436N (SD = 0.768). There was a significant difference between PFFG and PFR (p = 0.005). There was no statistical significance in the relationship between the other groups.

PCL reinforcement of collagen scaffolds provide an innovative solution for improving stiffness of the construct, allowing easier handling for the surgeon. Increasing the stiffness of the scaffold also allows press fit solutions for reliable fixation. Press fit PCL collagen scaffolds with and without fibrin glue provide dependable stability. Tensile testing provides an objective analysis of scaffold fixation. Further investigation of PCL collagen scaffolds in a live animal model to establish quality of osteochondral tissue regeneration are required.

Tibiotalocalcaneal arthrodesis (TTCA) is a salvage procedure to functionally block the ankle and subtalar joints to treat severe ankle and hindfoot disease. Complication rates range between 20-40%, with below-knee amputation rate 1.5-19%. The heterogeneous patient cohort and indication(s) for surgery make post-operative outcomes difficult to predict. Consulting patients about potential pain and functional outcomes is difficult. When researching this area commonly, PROM data is used, less frequently functional objective measures like the 2-minute-walk-test (2MWT) are used. The aim was to compare the PROMs and objective outcomes between patients who underwent TTCA and BKA.

Fifty-two patients underwent a TTCA using an intramedullary hindfoot nail. Indications for TTCA, post-traumatic OA, failed arthrodesis and malalignment. These patients were compared to 11 patients who underwent unilateral below knee amputation (BKA) due to trauma. Outcomes measures PROMs AOFAS ankle hindfoot scale and Shor-Form 36 (SF-36). Objective measures; 2MWT, Timed-up-and-go (TUG).

Mean age TTCA 55.9, BKA 46.4. Average follow-up time 53 months. TTCA group had average 6.3 operations prior to arthrodesis (range 1-23). Of the TTCA group two ankles did not unite (7%), all complication rate 35%, 18% reported no pain. A significant negative correlation was demonstrated between the clinical outcome and the number of surgeries prior to the TTCA. TUG and 2MWT had significantly (p<0.05) better outcomes for the BKA group compared to TTCA. SF-36 BKA patients scored higher than the TTCA patients on physical functioning (p<0.01) and mental health (p<0.05) subscales as well as the mental component score (p<0.05).

This study gives clinicians evidence about the natural history of hindfoot arthrodesis and functional outcomes from BKA. Hopefully this study will improve evidence to help patients and surgeons make decisions about expected surgical outcomes from TTCA and BKA procedures.

Local antimicrobial therapy is an integral aspect of treating orthopaedic device related infection (ODRI), which is conventionally administered via polymethylmethacrylate (PMMA) bone cement. PMMA, however, is limited by a suboptimal antibiotic release profile and a lack of biodegradability.

In this study, we compare the efficacy of PMMA versus an antibioticloaded hydrogel in a single- stage revision for chronic methicillin-resistant Staphylococcus aureus (MRSA) ODRI in

sheep. Antibiofilm activity of the antibiotic combination (gentamicin and vancomycin) was determined in vitro. Swiss alpine sheep underwent a single-stage revision of a tibial intramedullary nail with MRSA infection. Local gentamicin and vancomycin therapy was delivered via hydrogel or PMMA (n = 5 per group), in conjunction with systemic antibiotic therapy. In vivo observations included: local antibiotic tissue concentration, renal and liver function tests, and quantitative microbiology on tissues and hardware post-mortem.

There was a nonsignificant reduction in biofilm with an increasing antibiotic concentration in vitro (p = 0.12), confirming the antibiotic tolerance of the MRSA biofilm. In the in vivo study, four out of five sheep from each treatment group were culture negative. Antibiotic delivery via hydrogel resulted in 10–100 times greater local concentrations for the first 2–3 days compared with PMMA and were comparable thereafter. Systemic concentrations of gentamicin were minimal or undetectable in both groups, while renal and liver function tests were within normal limits.

This study shows that a single-stage revision with hydrogel or PMMA is equally effective, although the hydrogel offers certain practical benefits over PMMA, which make it an attractive proposition for clinical use.

Smartphone-based apps that measure step-count and patient reported outcomes (PROMs) are being increasingly used to quantify recovery in total hip arthroplasty (THA). However, optimum patient-specific activity level before and during THA early-recovery is not well characterised. This study investigated 1) correlations between step-count and PROMs and 2) how patient demographics impact step-count preoperatively and during early postoperative recovery.

Smartphone step-count and PROM data from 554 THA patients was retrospectively reviewed. Mean age was 64±10yr, BMI was 29±13kg/m2, 56% were female. Mean daily step count was calculated over three time-windows: 60 days prior to surgery (preop), 5-6 weeks postop (6wk), and 11-12 weeks postop (12wk).

Linear correlations between step-count and HOOS12 Function and UCLA activity scores were performed. Patients were separated into three step-count levels: low (<2500steps/day), medium (2500-5500steps/day), and high (>5500steps/day). Age >65years, BMI >30, and sex were used for demographic comparisons.

Student's t-tests determined significant differences in mean step-counts between demographic groups and in mean PROMs between step-count groups.

UCLA correlated with step-count at all time-windows (p<0.01). HOOS12 Function correlated with step-count preoperatively and at 6wk (p<0.01). High vs low step count individuals had improved UCLA scores preoperatively (∆1.8,p<0.001), at 6wk (∆1.1,p<0.05), and 12wk (∆1.6,p<0.01), and improved HOOS12 Function scores preoperatively (∆8.4,p<0.05) and at 6wk (∆8.8,p<0.001).

Younger patients had greater step-count preoperatively (4.1±3.0k vs 3.0±2.5k, p<0.01) and at 12wk (5.1±3.3k vs 3.6±2.9k, p<0.01). Males had greater step-count preoperatively (4.1±3.0k vs. 3.0±2.7k, p<0.001), at 6wk (4.5±3.2k vs 2.6±2.5k, p<0.001), and at 12wk (5.2±3.6k vs. 3.4±2.5k, p<0.001). Low BMI patients had greater step-count at 6wk (4.3±3.3k vs. 2.6±2.7k, p<0.01) and 12wk (5.0±3.6k vs. 3.6±2.6k, p<0.05).

Daily step-count is significantly impacted by patient demographics and correlates with PROMs, where patients with high step count exhibit improved PROMs. Generic recovery profiles may therefore not be appropriate for benchmarking across diverse populations.

Failure of cephalomedullary fixation for proximal femur fractures is an uncommon event associated with significant morbidity to the patient and cost to the healthcare system. This institution changed nailing system from the PFNA (DePuy Synthes) to InterTan (Smith and Nephew) in February 2020. To assess for non-inferiority, a retrospective review was performed on 247 patients treated for unstable proximal femur fractures (AO 31 A2; A3).

Patients were identified through manual review of fluoroscopic images. Stable fracture patterns were excluded (AO 31 A1). Pre/post operative imaging, demographic data, operative time and ASA scores assessed. Internal/external imaging and national joint registry data were reviewed for follow up.

No significant difference was found in overall failure rate of PFNA vs InterTan (4.84% vs 3.23%; p = 0.748). Overall, short nails were more likely to fail by cut-out than long nails (7.5% vs 1.2%; p = 0.015). Nails which failed by varus cut-out had a higher tip/apex distance (TAD) (26.2mm vs 17.0mm; p < 0.001). Of concern, varus cut-out occurred in two InterTan nails with TAD of <25mm. The PFNA enjoyed a shorter operative time for both the short (59.1 vs 71.8 mins; p = 0.022) and long nails (98.8 vs 114.3 mins; p = 0.016) with no difference in 120-day survival rate.

Overall failure rates of the PFNA and InterTan nailing systems were comparable. However, the failure rate of short nails in this study is concerning. Using long nails with a lag screw design for unstable intertrochanteric femoral fractures may reduce failure rates. Cumulative frequency analysis suggests stringent tip-apex distances of less than 21mm may reduce failure rates in lag-screw design cephulomedullary nails. This dataset suggests that unstable intertrochanteric fractures may be more reliably managed with a long cephalomedullary device.

Australian Football (AF) is a popular sport in Australia, with females now representing one-third of participants. Despite this, the injury profiles of females versus males in largely unknown. The current study investigated fractures, dislocations and tendon ruptures in females versus males presenting to emergency departments (ED) with an AF injury.

All patients, regardless of age, presenting to one of 10 EDs in Victoria, Australia, with an AF injury were included. Data were prospectively collected over a 10-month period, coinciding with a complete AF season. Data were extracted from patient medical records regarding injury-type, body-part injured and treatments required. Female and male data were compared with chi-squared tests.

Of the 1635 patients presenting with an AF injury, 595 (36.0%) had a fracture, dislocation or tendon rupture, of whom 85 (14.3%) were female and the average age was 20.5 years (SD 8.0). Fractures accounted for most injuries (n=478, 80.3% of patients had a fracture), followed by dislocations (n=118, 19.8%) and tendon ruptures (n=14, 2.4%). Upper limb fractures were more common than lower limb fractures (71.1% v 11.5% of fractures). Females were more likely to fracture their hands or fingers than males (45.7% v 34.3%). Males were more likely to fracture ribs (5.4% v 0%). Most fractures (91.2%) were managed in the ED, with the remainder being admitted for surgery (GAMP/ORIF). Males were more likely to be admitted for surgery than females (11.2% v 5.9%). Regarding dislocations (n=118), females were more likely to dislocate the patella (36.8% v 8.1% of dislocations). Only males sustained a tendon rupture (n=14): finger extensor or flexor (57.1%), achilles tendon (28.6%) and patella tendon (14.3%).

Orthopaedic AF injuries are common presentations to EDs in Victoria, though few require specialist orthopaedic intervention. Injury profiles differed between genders suggesting that gender specific injury prevention and management might be required.

The prevalence of gluteal tendinopathy (GT) associated with osteoarthritis of the hip is difficult to determine as it is frequently undiagnosed or misdiagnosed as trochanteric bursitis. Its relationship to total hip arthroplasty (THA) outcomes is currently unknown. The aim of this study was to determine the incidence of GT at the time of hip arthroplasty and examine the relationship between GT and patient reported outcomes (PROMS) before and after THA.

Patients undergoing THA for primary osteoarthritis between August 2017 and August 2020 were recruited. Tendinopathy was assessed and graded at time of surgery. PROMS included the Oxford Hip Score (OHS), HOOS JR, EQ-5D, and were collected preoperatively and at one year after THA. Satisfaction with surgery was also assessed at 1 year.

797 patients met eligibility criteria and were graded as Grade 1: normal tendons (n =496, 62%), Grade 2: gluteal tendinopathy but no tear (n=222, 28%), Grade 3: partial/full thickness tears or bare trochanter (n=79, 10%). Patients with abnormal gluteal tendons were older (p=0.001), had a higher mean BMI (p=0.01), and were predominately female (p=0.001). Patients with higher grade tendinopathy had statistically significant inferior PROMS at one year, OHS score (44.1 v 42.9 v 41.3, p 0.001) HOOS JR (89.3 V 86.3 V 85.6 p 0.005). Increasing gluteal tendon grade was associated with a greater incidence of problems with mobility (p=0.001), usual activities (p=0.001) and pain (p=0.021) on EQ5D. There was a 3 times relative risk of overall dissatisfaction with THA in the presence of gluteal tears.

This study demonstrated that gluteal tendinopathy was commonly observed and associated with inferior 1-year PROMS in patients undergoing THA for OA. Increasing degree of tendinopathy was a negative prognostic factor for worse functional outcomes and patient satisfaction.

The influence of patient age on functional outcomes after periacetabular osteotomy (PAO) for acetabular dysplasia remains unclear, with previous studies utilising scores developed for older, arthritic patients. The purpose of this study is to assess the influence of patient age on International Hip Outcome Tool (iHOT-12) scores, two years after PAO.

Eighty-six patients (72 female, 14 male; mean age 26.9 years) who underwent PAO by a single surgeon and had completed a minimum of two years follow up were identified. Patients were categorised into three groups according to age at the time of surgery: adolescent (11-20 years; n=29), young adult (21–30 years; n=29), and mature (≥31 years; n=28). The three groups were compared with respect to baseline variables and functional outcomes (iHOT-12, EQ-5D quality of life score, University of California Los Angeles (UCLA) activity score, pain visual analogue score (VAS)). Multivariate regression was undertaken to assess for independent predictors of two-year iHOT-12 score.

The adolescent group demonstrated a lower BMI (p=0.004) while the mature group had a greater American Society of Anaesthesiology (ASA) score (p=0.049). There were otherwise no significant differences in baseline variables between the three groups (all p>0.05).

The three groups demonstrated significant post-operative improvements across all functional outcome measures. There were no significant differences in two-year iHOT-12, EQ-5D, UCLA score or pain VAS between the three groups (all p>0.05). Regression modelling found that patient age at the time of surgery did not have an independent effect on two-year iHOT-12 score (p=0.878).

We found that patient age at the time of surgery did not influence functional outcomes two years after PAO. Our results suggest that patient age should not be considered in isolation as an indication or contraindication for PAO.

Autologous tendon cell injection (ATI) is a promising non-surgical treatment for tendinopathies and tendon tear that address its underlying pathology. The procedure involves harvesting autologous tendon tissue, the isolation of the tendon cells, expansion under quality assured GMP cell laboratory and the injection of the tendon cells via U/S into the degenerative tendon tissue. In clinical practice, the patella (PT) and palmaris longus (PL) tendons are common sites used for tendon tissue biopsy. The objective of this study is to compare the tendon cell quality, identity, purity, doubling time and yield of cells between PT and PL tendons for ATI.

Tendon tissue biopsies were harvested from PT via U/S using a 14-gauge needle or resected surgically from the PL tendon. The biopsies were transported to a GMP cell laboratory, where tendon cells were isolated, cultured and expanded for 4 to 6 weeks, and analysed for viability, cell doubling time, cellular characteristics including cell purity, potency and identity (PPI).

Tendon samples from 149 patients were analysed (63 PT). Average biopsy weight was 62mg for PT and 119mg for PI (p<0.001). Average cell doubling time (83.9 vs 82.7 hours), cellular yield (16.2 vs 15.2×106), viability (98.7 vs 99.0%) and passage number (3 vs 3) were not significantly different between tendons. Additionally, ddPCR analyses showed no differences of PPI including tendon cell markers of collagen type I, scleraxis and tenomodulin. No post-biopsy complications or contamination were reported for either group. Assessing tendon tissue from palmaris tendon is relatively easier.

Tendon tissue biopsy tissue for autologous tendon cell therapy can be obtained from either the PT or PL tendons. Tendon cells isolated from PT and PL were equal in growth characteristics and PPI. There are no differences in the quality of tendon cells isolated from the PT or PL.

Dislocation is one of the most common complications in total hip arthroplasty (THA) and is primarily driven by bony or prosthetic impingement. The aim of this study was two-fold. First, to develop a simulation that incorporates the functional position of the femur and pelvis and instantaneously determines range of motion (ROM) limits. Second, to assess the number of patients for whom their functional bony alignment escalates impingement risk.

468 patients underwent a preoperative THA planning protocol that included functional x-rays and a lower limb CT scan. The CT scan was segmented and landmarked, and the x-rays were measured for pelvic tilt, femoral rotation, and preoperative leg length discrepancy (LLD). All patients received 3D templating with the same implant combination (Depuy; Corail/Pinnacle). Implants were positioned according to standardised criteria.

Each patient was simulated in a novel ROM simulation that instantaneously calculates bony and prosthetic impingement limits in functional movements. Simulated motions included flexion and standing-external rotation (ER). Each patient's ROM was simulated with their bones oriented in both functional and neutral positions.

13% patients suffered a ROM impingement for functional but not neutral extension-ER. As a result, 48% patients who failed the functional-ER simulation would not be detected without consideration of the functional bony alignment. 16% patients suffered a ROM impingement for functional but not neutral flexion. As a result, 65% patients who failed the flexion simulation would not be detected without consideration of the functional bony alignment.

We have developed a ROM simulation for use with preoperative planning for THA surgery that can solve bony and prosthetic impingement limits instantaneously. The advantage of our ROM simulation over previous simulations is instantaneous impingement detection, not requiring implant geometries to be analysed prior to use, and addressing the functional position of both the femur and pelvis.

Iliopsoas tendonitis occurs in up to 30% of patients after hip resurfacing arthroplasty (HRA) and is a common reason for revision. The primary purpose of this study was to validate our novel computational model for quantifying iliopsoas impingement in HRA patients using a case-controlled investigation. Secondary purpose was to compare these results with previously measured THA patients.

We conducted a retrospective search in an experienced surgeon's database for HRA patients with iliopsoas tendonitis, confirmed via the active hip flexion test in supine, and control patients without iliopsoas tendonitis, resulting in two cohorts of 12 patients. The CT scans were segmented, landmarked, and used to simulate the iliopsoas impingement in supine and standing pelvic positions. Three discrete impingement values were output for each pelvic position, and the mean and maximum of these values were reported. Cup prominence was measured using a novel, nearest-neighbour algorithm.

The mean cup prominence for the symptomatic cohort was 10.7mm and 5.1mm for the asymptomatic cohort (p << 0.01). The average standing mean impingement for the symptomatic cohort was 0.1mm and 0.0mm for the asymptomatic cohort (p << 0.01). The average standing maximum impingement for the symptomatic cohort was 0.2mm and 0.0mm for the asymptomatic cohort (p << 0.01). Impingement significantly predicted the probability of pain in logistic regression models and the simulation had a sensitivity of 92%, specificity of 91%, and an AUC ROC curve of 0.95.

Using a case-controlled investigation, we demonstrated that our novel simulation could detect iliopsoas impingement and differentiate between the symptomatic and asymptomatic cohorts. Interestingly, the HRA patients demonstrated less impingement than the THA patients, despite greater cup prominence. In conclusion, this tool has the potential to be used preoperatively, to guide decisions about optimal cup placement, and postoperatively, to assist in the diagnosis of iliopsoas tendonitis.

In the unstable patellofemoral joint (PFJ), the patella will articulate in an abnormal manner, producing an uneven distribution of forces. It is hypothesised that incongruency of the PFJ, even without clinical instability, may lead to degenerative changes. The aim of this study was to record the change in joint contact area of the PFJ after stabilisation surgery using an established and validated MRI mapping technique.

A prospective MRI imaging study of patients with a history of PFJ instability was performed. The patellofemoral joints were imaged with the use of an MRI scan during active movement from 0° through to 40° of flexion. The congruency through measurement of the contact surface area was mapped in 5-mm intervals on axial slices. Post-stabilisation surgery contact area was compared to the pre-surgery contact area.

In all, 26 patients were studied. The cohort included 12 male and 14 female patients with a mean age of 26 (15-43). The greatest mean differences in congruency between pre- and post-stabilised PFJs were observed at 0-10 degrees of flexion (0.54 cm² versus 1.18 cm², p = 0.04) and between 11° and 20° flexion (1.80 cm² versus 3.45 cm²; p = 0.01).

PFJ stabilisation procedures increase joint congruency. If a single axial series is to be obtained on MRI scan to compare the pre- and post-surgery joint congruity, the authors recommend 11° to 20° of tibiofemoral flexion as this was shown to have the greatest difference in contact surface area between pre- and post-operative congruency.

Iliopsoas impingement occurs in between 5-30% of patients after hip arthroplasty and has been thought to only be caused by an oversized cup, cup malpositioning, or the depth of the psoas valley. However, no study has associated the relationship between preoperative measurements with the risk of impingement. This study sought to assess impingement between the iliopsoas and acetabular cup using a novel validated model to determine the risk factors for iliopsoas impingement.

413 patients received lower limb CT scans and lateral x-rays that were segmented, landmarked, and measured using a validated preoperative planning protocol. Implants were positioned according to the preference of ten experienced surgeons. The segmented bones were transformed to the standing reference frame and simulated with a novel computational model that detects impingement between the iliopsoas and acetabular cup. Definitions of patients at-risk and not at-risk of impingement were defined from a previous validation study of the simulation. At-risk patients were propensity score matched to not at-risk patients.

21% of patients were assessed as being at-risk of iliopsoas impingement. Significant differences between at-risk patients and not at-risk patients were observed in standing pelvic tilt (p << 0.01), standing femoral internal rotation (p << 0.01), medio-lateral centre-of-rotation (COR) change (p << 0.01), supine cup anteversion (p << 0.01), pre- to postoperative cup offset change (p << 0.001), postoperative gross offset (p = 0.009), and supero-inferior COR change (p = 0.02).

Impingement between the iliopsoas and acetabular cup is under-studied and may be more common than is published in the literature. Previously it has been thought to only be related to cup size or positioning. However, we have observed significant differences between at-risk and not at-risk patients in additional measurements. This indicates that its occurrence is more complex than simply being related to cup position.

While clinically important improvements in Oxford Shoulder Scores have been defined for patients with general shoulder problems or those undergoing subacromial decompression, no threshold has been reported for classifying improvement after shoulder replacement surgery. This study aimed to establish the minimal clinically important change (MCIC) for the Oxford Shoulder Score in patients undergoing primary total shoulder replacement (TSR).

Patient-reported outcomes data were sourced from the Australian Orthopaedic Association National Joint Replacement Registry Patient-Reported Outcome Measures Program. These included pre- and 6-month post-operative Oxford Shoulder Scores and a rating of patient-perceived change after surgery (5-point scale ranging from ‘much worse’ to ‘much better’). Two anchor-based methods (using patient-perceived improvement as the anchor) were used to calculate the MCIC: 1) mean change method; and 2) predictive modelling, with and without adjustment for the proportion of improved patients.

The analysis included 612 patients undergoing primary TSR who provided pre- and post-operative data (58% female; mean (SD) age 70 (8) years). Most patients (93%) reported improvement after surgery. The MCIC derived from the mean change method was 6.8 points (95%CI 4.7 to 8.9). Predictive modelling produced an MCIC estimate of 11.6 points (95%CI 8.9 to 15.6), which reduced to 8.7 points (95%CI 6.0 to 12.7) after adjustment for the proportion of improved patients.

For patient-reported outcome measures to provide valuable information that can support clinical care, we need to understand the magnitude of change that matters to patients. Using contemporary psychometric methods, this analysis has generated MCIC estimates for the Oxford Shoulder Score. These estimates can be used by clinicians and researchers to interpret important changes in pain and function after TSR from the patient's perspective. We conclude that an increase in Oxford Shoulder Scores of at least 9 points can be considered a meaningful improvement in shoulder-related pain and function after TSR.

Human error is usually evaluated using statistical descriptions during radiographic annotation. The technological advances popularized the “non-human” landmarking techniques, such as deep learning, in which the error is presented in a confidence format that is not comparable to that of the human method. The region-based landmark definition makes an arbitrary “ground truth” point impossible. The differences in patients’ anatomies, radiograph qualities, and scales make the horizontal comparison difficult. There is a demand to quantify the manual landmarking error in a probability format.

Taking the measurement of pelvic tilt (PT) as an example, this study recruited 115 sagittal pelvic radiographs for the measurement of two PTs. We proposed a method to unify the scale of images that allows horizontal comparisons of landmarks and calculated the maximum possible error using a density vector. Traditional descriptive statistics were also applied.

All measurements showed excellent reliabilities (intraclass correlation coefficients > 0.9). Eighty-four measurements (6.09%) were qualified as wrong landmarks that failed to label the correct locations. Directional bias (systematic error) was identified due to cognitive differences between observers. By removing wrong labels and rotated pelves, the analysis quantified the error density as a “good doctor” performance and found 6.77°-11.76° maximum PT disagreement with 95% data points.

The landmarks with excellent reliability still have a chance (at least 6.09% in our case) of making wrong landmark decisions. Identifying skeletal contours is at least 24.64% more accurate than estimating landmark locations. The landmark at a clear skeletal contour is more likely to generate systematic errors. Due to landmark ambiguity, a very careful surgeon measuring PT could make a maximum 11.76° random difference in 95% of cases, serving as a “good doctor benchmark” to qualify good landmarking techniques.

Source of the study: University of Auckland, Auckland, New Zealand and University of Otago, Christchurch, New Zealand

The Oxford Knee Score (OKS) is a 12-item questionnaire used to track knee arthroplasty outcomes. Validation of such patient reported outcome measures is typically anchored to a single question based on patient ‘satisfaction’, however risk of subsequent revision surgery is also an important outcome measure. The OKS can predict subsequent revision risk within two years, however it is not known which item(s) are the strongest predictors. Our aim was to identify which questions were most relevant in the prediction of subsequent knee arthroplasty revision risk.

All primary TKAs (n=27,708) and UKAs (n=8,415) captured by the New Zealand Joint Registry between 1999 and 2019 with at least one OKS response at six months, five years or ten years post-surgery were included. Logistic regression and receiver operating characteristics (ROC) curves were used to assess prediction models at six months, five years and ten years.

Q1 ‘overall pain’ was the strongest predictor of revision within two years (TKA: 6 months, odds ratio (OR) 1.37; 5 years, OR 1.80; 10 years, OR 1.43; UKA: 6 months, OR 1.32; 5 years, OR 2.88; 10 years, OR 1.85; all p<0.05). A reduced model with just three questions (Q1, Q6 ‘limping when walking’, Q10 ‘knee giving way’) showed comparable or better diagnostic ability with the full OKS (area under the curve (AUC): TKA: 6 months, 0.77 vs. 0.76; 5 years, 0.78 vs. 0.75; 10 years, 0.76 vs. 0.73; UKA: 6 months, 0.80 vs. 0.78; 5 years: 0.81 vs. 0.77; 10 years, 0.80 vs. 0.77).

The three questions on overall knee pain, limping when walking, and knee ‘giving way’ were the strongest predictors of subsequent revision within two years. Attention to the responses for these three key questions during follow-up may allow for prompt identification of patients most at risk of revision.

Utility score is a preference-based measure of general health state – where 0 is equal to death, and 1 is equal to perfect health. To understand a patient's smallest perceptible change in utility score, the minimal clinically important difference (MCID) can be calculated. However, there are multiple methods to calculate MCID with no consensus about which method is most appropriate. The aim of this study is to calculate MCID values for the Veterans-RAND 12 (VR12) utility score using varying methods. Our hypothesis is that different methods will yield different MCID values.

A tertiary institutional registry (SMART) was used as the study cohort. Patients who underwent unilateral TKA for osteoarthritis from January 2012 to January 2020 were included. Utility score was calculated from VR12 responses using the standardised Brazier's method. Distribution and anchor methods were used for the MCID calculation. For distribution methods, 0.5 standard deviations of the baseline and change scores were used. For anchor methods, the physical and emotional anchor questions in the VR12 survey were used to benchmark utility score outcomes. Anchor methods included mean difference in change score, mean difference in 12 month score, and receiver operating characteristics (ROC) analysis with the Youden index.

Complete case analysis of 1735 out of 1809 eligible patients was performed. Significant variation in the MCID estimates for VR12 utility score were reported dependent on the calculation method used. The MCID estimate from 0.5 standard deviations of the change score was 0.083. The MCID estimate from the ROC analysis method using physical or emotional anchor question improvement was 0.115 (CI95 0.08-0.14; AUC 0.656).

Different MCID calculation methods yielded different MCID values. Our results suggest that MCID is not an umbrella concept but rather many distinct concepts. A general consensus is required to standardise how MCID is defined, calculated, and applied in clinical practice.

Introduction

With advances in mobile application, digital health is being increasingly used for remote and personalised care. Patient education, self-management and tele communication is a crucial factor in optimising outcomes.

BACKGROUND

Theatre-listed trauma patients routinely require two ‘group and save’ blood-bank samples, in case they need perioperative transfusion. The Welsh Blood Service (WBS) need patients to have one recorded sample from any time in the last 10 years. A second sample, to permit cross-matching and blood issuing, must be within 7 days of transfusion (or within 48 hours if the patient is pregnant, or has been transfused within the last 3 months). The approximate cost of processing a sample is £15.00.

Aims

The microbiological detection of microorganisms plays a crucial role in the diagnosis as well as in the targeted systemic and local antibiotic therapy of periprosthetic infections (PJI). Despite extensive efforts to improve the sensitivity of current culture methods, the rate of culture-negative infections is approximately 10–20% of all PJI. This study investigates an preanalytical algorithm (culture collection and direct processing in the OR) to potentially increasing culture yield in patients with PJI.

Aim

The aim of this study was to investigate the clinical relevance of an isolated positive sonication fluid culture (SFC) in patients who underwent revision surgery of a prosthetic joint. We hypothesized that cases with a positive SFC have a higher rate of infection and prosthesis failure during follow-up compared to controls with a negative SFC.

Traditionally, sports Injuries have been sub-optimally managed through Emergency Departments (ED) in the public health system due to a lack of adequate referral processes. Fractures are ruled out through plain radiographs followed by a reactive process involving patient initiated further follow up and investigation. Consequently, significant soft tissue and chondral injuries can go undiagnosed during periods in which early intervention can significantly affect natural progression. The purpose of this quality improvement project was to assess the efficacy of an innovative Sports Injury Pathway introduced to detect and treat significant soft tissue injuries.

A Sports Injury Pathway was introduced at Fiona Stanley Hospital (WA, Australia) in April 2019 as a collaboration between the ED, Physiotherapy and Orthopaedic Departments. ED practitioners were advised to have a low threshold for referral, especially in the presence of a history of a twisting knee injury, shoulder dislocation or any suggestion of a hip tendon injury. All referrals were triaged by the Perth Sports Surgery Fellow with early follow-up in our Sports Trauma Clinics with additional investigations if required. A detailed database of all referrals was maintained, and relevant data was extracted for analysis over the first 3 years of this pathway.

570 patients were included in the final analysis. 54% of injuries occurred while playing sport, with AFL injuries constituting the most common contact-sports injury (13%). Advanced Scope Physiotherapists were the largest source of referrals (60%). A total of 460 MRI scans were eventually ordered comprising 81% of total referrals. Regarding Knee MRIs, 86% identified a significant structural injury with ACL injuries being the most common (33%) followed by isolated meniscal tears (16%) and multi-ligament knee injuries (11%). 95% of Shoulder MRI scans showed significant pathology. 39% of patients required surgical management, and of these 50% were performed within 3 months from injury.

The Fiona Stanley Hospital Sports Injury Pathway has demonstrated its clear value in successfully diagnosing and treating an important cohort of patients who present to our Emergency Department. This low threshold/streamlined referral pathway has found that the vast majority of these patients suffer significant structural injuries that may have been otherwise missed, while providing referring practitioners and patients access to prompt imaging and high-quality Orthopaedic sports trauma services. We recommend the implementation of a similar Sports Injury Pathway at all secondary and tertiary Orthopaedic Centres.

Children with osteogenesis imperfecta (OI) frequently present with coxa vara (CV). Skeletal fragility, severe deformity and limited fixation options make this a challenging condition to correct surgically. Our study aimed to determine the efficacy of the Fassier technique to correct CV and determine the complication rate.

Retrospective, descriptive case series from a tertiary hospital. We retrospectively reviewed records of a cohort of eight children (four females, 12 hips) with OI (6/8 Sillence type III, 2/8 type IV) who had surgical treatment with Fassier technique for CV between 2014 and 2020.

Inclusion Criteria: All patients with CV secondary to OI treated surgically with Fassier technique.

Exclusion Criteria: Patients older than 18 years; Patients with CV treated non-operatively or by surgical technique different to Fassier technique.

Data relating to the following parameters was collected and analyzed: demographic data, pre- and postoperative neck shaft angle (NSA), complications and NSA at final follow-up.

The mean age at operation was 5.8 years (range 2–10). The mean NSA was corrected from 96.8° preoperatively to 137º postoperatively. At a mean follow-up of 38.6 months, the mean NSA was maintained at 133°, and 83% (10/12) of hips had an NSA that remained greater than 120°. There was a 42% (5/12) complication rate: three Fassier–Duval rods failed to expand after distal epiphyseal fixation was lost during growth; one Rush rod migrated through the lateral proximal femur cortex with recurrent coxa vara; and one Rush rod migrated proximally and required rod revision.

The Fassier technique effectively corrected CV in children with moderate and progressively deforming OI. The deformity correction was maintained in the short term. The complication rate was high, but mainly related to the failed expansion of the Fassier–Duval rods.

Complex regional pain syndrome type 1 (CRPS-I) is a devastating complication that can occur after limb extremity injuries. The effectiveness of vitamin C in preventing CRPS-I incidence is debatable. Therefore, we conducted a systematic review and meta-analysis to assess the role of vitamin C in CRPS-I prevention and its effect on pain score, functional outcomes and complications rate after wrist, ankle, and foot fractures.

We searched Medline, Embase, the Cochrane Library, Clinicaltrial.gov, and Google Scholar from infinity to May 2021 for relevant studies comparing the incidence of CRPS-I with administration of perioperative vitamin C versus placebo after wrist, ankle, and foot fractures. Continuous data such as functional outcomes and pain scores were pooled as mean differences (MD), whist dichotomous variables such as the incidence of CRPS-I and complications were pooled as odds ratios (OR), with 95% confidence interval (CI). Data analyses was done using R software (meta package, version 4.9-0) for Windows.

Eight studies, including two quasi-experimental studies, were included. The timeframe for vitamin C administration ranged from 42 to 50 days post-injury and/or surgical fixation and the dosage was either 500 mg or 1000 mg. The results showed that vitamin C was associated with a lower rate of CRPS-I relative to a placebo (OR 0.33, 95% CI [0.17, 0.63]). No significant difference was found between vitamin C and placebo in terms of complications (OR 1.90, 95% CI [0.99, 3.65]), functional outcomes (MD 6.37, 95% CI [-1.40, 14.15]), and pain scores (MD −0.14, 95% CI [-1.07, 0.79]).

The findings demonstrate that when compared to placebo, at least 42 days of vitamin C prophylaxis is associated with prevention of CRPS-I following wrist, ankle, and foot fractures, irrespective of vitamin C dosage or fracture type. No significant differences were found with secondary outcomes.

Ankle fractures represent the third most common fragility fracture seen in elderly patients following hip and distal radius fractures. Non-operative management of these see complication rates as high as 70%. Open reduction and internal fixation (ORIF) has complication rates of up to 40%. With either option, patients tend to be managed with a non-weight bearing period of six weeks or longer. An alternative is the use of a tibiotalocalcaneal (TTC) nail. This provides a percutaneous treatment that enables the patient to mobilise immediately. This case-series explores the efficacy of this device in a broad population, including the highly comorbid and cognitively impaired.

We reviewed patients treated with TTC nail for acute ankle fractures between 2019 and 2022. Baseline and surgical data were collected. Clinical records were reviewed to record any post-operative complication, and post-operative mobility status and domicile. 24 patients had their ankle fracture managed with TTC nailing. No intra-operative complications were noted. There were six (27%) post-operative complications; four patients had loosening of a distal locking screw, one significant wound infection necessitating exchange of nail, and one pressure area from an underlying displaced fracture fragment. All except three patients returned to their previous domicile. Just over two thirds of patients returned to their baseline level of mobility.

This case-series is one of the largest and is also one of the first to include cognitively impaired patients. Our results are consistent with other case-series with a favourable complication rate when compared with ORIF in similar patient groups. The use of a TTC nail in the context of acute, geriatric ankle trauma is a simple and effective treatment modality. This series shows acceptable complication rates and the majority of patients are able to return to their baseline level of mobility and domicile.

Distal radius fractures are common in South Africa. Accurate, decisive radiographic parameter interpretation is key in appropriate management. Digital radiographic facilities are rare in the public setting and goniometer usage is known to be low, thus, visual estimates are the primary form of radiographic assessment. Previous research associated orthopaedic experience with accuracy of distal radius fracture parameter estimation but, oftentimes, doctors treating orthopaedic patients are not experienced in orthopaedics.

A cross-sectional questionnaire including four distal radius fracture radiographs administered to 149 orthopaedic doctors at three Johannesburg teaching hospitals. Participants grouped into ranks of: consultants (n=36), registrars (n=41), medical officers (n=20) and interns (n=52). Participants visually estimated values of distal radius fracture parameters, stated whether they would accept the position of the fractures and stated their percentage of routine usage of goniometers in real practice.

The registrar group was most accurate in visually estimating radial height, whilst the interns were least accurate (p=0.0237). The consultant, registrar and medical officer groups were equally accurate in estimating radial inclination whilst the intern group was the least accurate (p<0.0001). The consultant and registrar group were equally accurate at estimating volar tilt, whilst the medical officer and intern groups were least accurate (p<0.0001). The Gwet's AC agreement was 0.1612 (p=0.047) for acceptance of position of the first radiograph, 0.8768 (p<0.0001) for the second, 0.8884 (p<0.0001) for the third and 0.8064 (p<0.0001) for the fourth. All groups showed no difference in goniometer usage, using them largely 0–25% of practice (p=0.1937).

The study found that accuracy in visual estimations of distal radius fracture parameters was linked to orthopaedic experience but not linked to routine practice goniometer usage, which was minimal across all groups. Inter-rater agreement on acceptability of fracture position is potentially dependent on severity of deviation from acceptable parameters.

Fractures of the distal radius are common, and form a considerable proportion of the trauma workload. We conducted a study to examine the patterns of injury and treatment for adult patients presenting with distal radius fractures to a major trauma centre serving an urban population.

We undertook a retrospective cohort study to identify all patients treated at our major trauma centre for a distal radius fracture between 1 June 2018 and 1 May 2021. We reviewed the medical records and imaging for each patient to examine patterns of injury and treatment. We undertook a binomial logistic regression to produce a predictive model for operative fixation or inpatient admission.

Overall, 571 fractures of the distal radius were treated at our centre during the study period. A total of 146 (26%) patients required an inpatient admission, and 385 surgical procedures for fractures of the distal radius were recorded between June 2018 and May 2021. The most common mechanism of injury was a fall from a height of one metre or less. Of the total fractures, 59% (n = 337) were treated nonoperatively, and of those patients treated with surgery, locked anterior-plate fixation was the preferred technique (79%; n = 180).

The epidemiology of distal radius fractures treated at our major trauma centre replicated the classical bimodal distribution described in the literature. Patient age, open fractures, and fracture classification were factors correlated with the decision to treat the fracture operatively. While most fractures were

Atypical femoral fracture non-union (AFFNU) is both, rare (3–5 per 1000 proximal femur fractures) and difficult to treat. Lack of standardised guidelines leads to a variability in fixation constructs, use of bone grafting and restricted weight bearing protocols, which are not evidence based. We hypothesised that there is no change in union rates without the use of bone grafting and immediate weight bearing post-operatively does not lead to increased complications.

The purpose of this study is to assess the long term results of combined ACL reconstruction and unicompartmental knee replacements (UKR). These patients have been selected for this combined operation due to their combination of instability symptoms from an absent ACL and unicompartmental arthritis.

Retrospective review of 44 combined UKR and ACL reconstruction by a single surgeon. Surgeries included both medial and lateral UKR combined with either revision ACL reconstruction or primary ACL reconstruction. Patient reported outcomes were obtained preoperatively, at one year, 5 years and 10 years. Revision rate was followed up over 13 years for a mean of 7.4 years post-surgery.

The average Oxford score at one year was 43 with an average increase from pre-operation to 1 year post operation of 15. For the 7 patients with 10 year follow up average oxford score was 42 at 1 year, 43 at 5 years and 45 at 10 years.

There were 5 reoperations. 2 for revision to total knee arthroplasty and 1 for an exchange of bearing due to wear. The other 2 were the addition of another UKR. For those requiring reoperation the average time was 8 years.

Younger more active patients presenting with ACL deficiency causing instability and unicompartmental arthritis are a difficult group to manage. Combining UKR and ACL reconstruction has scant evidence in regard to long term follow up but is a viable option for this select group. This paper has one of the largest cohorts with a reasonable follow up averaging 7.4 years and a revision rate of 11 percent.

Combined unilateral knee replacements and ACL reconstruction can be a successful operation for patients with ACL rupture causing instability and unicompartmental arthritis.

Aim

Diagnosis of periprosthetic shoulder infections (PSI) is difficult as they are mostly caused by low-virulent bacteria and patients do not show typical infection signs, such as elevated blood markers, wound leakage, or red and swollen skin. Ultrasound-guided biopsies for culture may therefore be an alternative for mini-open biopsies as less costly and invasive method. The aim of this study was to determine the diagnostic value and reliability of ultrasound-guided biopsies for cultures alone and in combination polymerase chain reaction (PCR), and/or synovial markers for preoperative diagnosis of PSI in patients undergoing revision shoulder surgery.

Introduction

Angular deformities of the distal femur can be corrected by opening, closing and neutral wedge techniques. Opening wedge (OW) and closing wedge (CW) are popular and well described in the literature. CW and OW techniques lead to leg length difference whereas the advantage of neutral wedge (NW) technique has several unique advantages. NW technique maintains limb length, wedge taken from the closing side is utilised on the opening side and since the angular correction is only half of the measured wedge on either side, translation of distal fragment is minimum. Leg lengths are not altered with this technique hence a useful technique in large deformities. We found no reports of clinical outcomes using NW technique. We present a technique of performing external fixator assisted NW correction of large valgus and varus deformities of distal femur and dual plating and discuss the results.

Obesity is a common in individuals undergoing arthroplasty, and the potential for weight loss with improved mobility may be expected by some. The aim of this study was 1. determine the proportion that achieved weight loss after hip or knee arthroplasty, and 2. examine the effect of obesity on patient reported outcomes (PROMS) and satisfaction with surgery.

Participants underwent primary TKA or THA between July 2015 and December 2020 and consented to participation in a research database with baseline PROMS, including weight, BMI, Oxford Knee, or Hip Score, and EQ5D. Participants repeated PROMS at 12 months after surgery with additional questions regarding satisfaction with surgery.

3449 patients completed PROMS 1 year after arthroplasty with weight and BMI. There were 1810 THA and 1639 TKA procedures. The mean baseline BMI was higher in TKA (29.8, SD 5.2) compared to THA (27.7, SD 5.0), p=0.001. A higher proportion of TKA were classified as obese class 1 (29% TKA, 19% THA), obese class 2 (11% TKA and 6% THA), and obese class 3 (5% TKA and 2% THA), p=0.001. The mean weight loss after 1 year was 0.4kg and 0.9kg in obese THA subjects and TKA subjects respectively. In the obese >5kg weight loss was achieved in 13% of TKA and 7% of THA (p=0.001). Obese experienced equivalent improvement in Oxford scores, compared to non-obese subjects. Satisfaction with surgery was reported by 95% of THA and 91% of TKA subjects with no significant differences between BMI group grades (p=0.491 THA and p=0.473 TKA).

Preoperative obesity was observed in 44% of TKA and 27% of THA subjects. In the obese only 1 in 10 subjects lost 5kg or more over 12 months. Obese patients experienced equivalent improvements in outcome after arthroplasty and rates of satisfaction with surgery to the non-obese.

ZrN-multilayer coating is clinically well established in total knee arthroplasty [1–3] and has demonstrated significant reduction in polyethylene wear and metal ion release [4,5].

The goal of our study was to analyze the biotribological behaviour of the ZrN-multilayer coating on a polished cobalt-chromium cemented hip stem.

CoCr28Mo6 alloy hip stems with ZrN-multilayer coating (CoreHip®AS) were tested versus an un-coated version. In a worst-case-scenario the stems with ceramic heads have been tested in bovine serum in a severe cement interface debonding condition under a cyclic load of 3,875 N for 15 million cycles. After 1, 3, 5, 10 & 15 million cycles the surface texture was analysed by scanning-electron-microscopy (SEM) and energy-dispersive x-ray (EDX). Metal ion concentration of Co,Cr,Mo was measured by inductively coupled plasma mass spectroscopy (ICP-MS) after each test interval.

Based on SEM/EDX analysis, it has been demonstrated that the ZrN-multilayer coating keeps his integrity over 15 million cycles of severe stem cemented interface debonding without any exposure of the CoCr28Mo6 substrate.

The ZrN-multilayer coated polished cobalt-chromium cemented hip stem has shown a reduction of Co & Cr metal ion release by two orders of a magnitude, even under severe stem debonding and high interface micro-motion conditions.

ZrN-multilayer coating on polished cobalt-chromium cemented hip stems might be a suitable option for further minimisation of Co & Cr metal ion release in total hip arthroplasty. Clinical evidence has to be proven during the next years.

Treatment of posterior malleolar (PM) ankle fractures remain controversial. Despite increasing recommendation for small PM fragment fixation, high quality evidence demonstrating improved clinical outcomes over the unfixated PM is limited. We describe the medium-to-long term clinical and radiographical outcomes in younger adult patients with PM ankle fractures managed without PM fragment fixation.

A retrospective cohort study of patients aged 18-55 years old admitted under our orthopaedic unit between 1st of April 2009 and 31st of October 2013 with PM ankle fractures was performed. Inclusion criteria were that all patients must mobilise independently pre-trauma, have no pre-existing ankle pathologies, and had satisfactory bimalleolar and syndesmotic stabilisation. Open fractures, talar fractures, calcaneal fractures, pilon fractures, subsequent re-injury and major complications were excluded. All PM fragments were unfixated. Clinical outcomes were evaluated using Foot and Ankle Ability Measure (FAAM) with activities of daily living (ADL) and sports subscale, visual analogue scale (VAS) and patient satisfaction ratings. Osteoarthrosis was assessed using modified Kellgren-Lawrence scale on updated weightbearing ankle radiographs.

61 participants were included. Mean follow-up was 10.26 years. Average PM size was 16.19±7.39%. All participants were evaluated for clinical outcomes, demonstrating good functional outcomes (FAAM-ADL 95.48±7.13; FAAM-Sports 86.39±15.52) and patient satisfaction (86.16±14.42%), with minimal pain (VAS 1.13±1.65). Radiographical outcomes were evaluated in 52 participants, showing no-to-minimal osteoarthrosis in 36/52 (69.23%), mild osteoarthrosis in 14/52 (26.92%) and moderate osteoarthrosis in 2/52 (3.85%). Clinical outcomes were not associated with PM fragment size, post-reduction step-off, dislocation, malleoli fractured or syndesmotic injury. PM step-off and dislocation were associated with worse radiographical osteoarthrosis. Other published medium-to-long term studies reported overall good outcomes, with no differences after small fragment fixation.

The unfixated smaller posterior malleolus fragment demonstrated overall satisfactory clinical and radiographical outcomes at 10-year follow-up and may be considered a valid treatment strategy.

Contemporary indications for unicompartmental knee replacement (UKR) include bone on bone radiographic changes in the medial compartment with relatively preserved lateral and patellofemoral compartments. The role of MRI in identifying candidates for UKR is commonplace. The aim of this study was to assess the relationship between radiographic and MRI pre-operative grade and outcome following UKR.

A retrospective analysis of medial UKR patients from 2017 to 2021. Inclusion criteria were medial UKR for osteoarthritis with pre-operative and post-operative Oxford Knee Scores (OKS), pre-operative radiographs and MRI.

89 patients were included. Whilst all patients had grade 4 ICRS scores on MRI, 36/89 patients had grade 3 KL radiographic scores in the medial compartment, 50/89 had grade 4 KL scores on the medial compartment. Grade 3 KL with grade 4 IRCS medial compartment patients had a mean OKS change of 17.22 (Sd 9.190) meanwhile Grade 4 KL had a mean change of 17.54 (SD 9.001), with no statistical difference in the OKS change score following UKR between these two groups (p=0.873). Medial bone oedema was present in all but one patient. Whilst lateral compartment MRI ICRS scores ranged from 1 to 4 there was no association with MRI score of the lateral compartment and subsequent change in oxford score (P value 0.458). Patellofemoral Compartment (PFC) MRI ICRS ranged from 0 to 4. There was no association between PFC ICRS score and subsequent change in oxford knee score (P value .276)

Radiographs may under report severity of some medial sided knee osteoarthritis. We conclude that in patients with grade 3 KL score that would normally not be considered for UKR, pre-operative MRI might identify grade 4 ICRS scores and this subset of patients have equivalent outcomes to patients with radiographic Grade 4 KL medial compartment osteoarthritis.

The incidence of PJI in knee replacements is 2.8% and slightly lower with hip replacement surgery. PJI make up 15% (or even more) of knee revisions. To combat PJI, antibiotic laden bone cement has been used for many decades, but antibiotic stewardship dictates more prudent management of antimicrobials. Projected increase in infection rate, due to increased surgery and latent infection to be almost 5-fold up to 2035.

Biofilm is a complex structure of bacteria and polysaccharide matrix and, is recognised as a major component in PJI and other orthopaedic infections.

Biofilm is responsible for high incidence of resistance to antimicrobials and ineffective host immune response.

The triangular fibrocartilage complex (TFCC) is a known stabiliser of the distal radioulnar joint (DRUJ). An injury to these structures can result in significant disability including pain, weakness and joint stiffness. The contribution each of its components makes to the stability of the TFCC is not well understood. This study was undertaken to investigate the role of the individual ligaments of the TFCC and their contribution to joint stability.

The study was undertaken in two parts. 30 cadaveric forearms were studied in each group. The ligaments of the TFCC were progressively sectioned and the resulting effect on the stability of the DRUJ was measured. A custom jig was created to apply a 20N force through the distal radius, with the ulna fixed.

Experiment one measured the effect on DRUJ translation after TFCC sectioning. Experiment two added the measurement of rotational instability.

Part one of the study showed that complete sectioning of the TFCC caused a mean increase in translation of 6.09(±3) mm. Sectioning the palmar radioulnar ligament of the TFCC caused the most translation.

Part two demonstrated a change in rotation with a mean of 18 (± 6) degrees following sectioning of the TFCC. There was a progressive increase in rotational instability until the palmar radioulnar ligament was also sectioned.

Linear translation consistently increased after sectioning all of the TFCC ligaments, confirming its importance for DRUJ stability. Sectioning of the palmar radioulnar ligament most commonly caused the greatest degree of translation. This suggests injury to this ligament would more likely result in a greater degree of translational instability. The increase in rotation also suggests that this type of instability would be symptomatic in a TFCC injury.

Aim

Bacteriophages are remerging as alternative and adjunctive therapy for fracture-related infection (FRI). However, current administration protocols involve prolonged retention of a percutaneous draining tube with potential risk of developing superinfection. In this study, we applied a cocktail of in vitro evolved biofilm-targeting phages for Methicillin-resistant Staphylococcus aureus (MRSA) in a hydrogel platform co-delivering vancomycin. In vitro synergy and antibiofilm activity was assessed and a subsequent in vivo study was performed in a mouse FRI model with MRSA.

The role of dual consultant operating (DCO) in general orthopaedics has not been researched; where it has shown benefit in other specialties, there is a lack of information on how DCO affects the surgeons themselves. We wanted to explore the potential effects of DCO on stress, as a foundation for further research to guide support for our surgeons.

We conducted a survey among orthopaedic consultants around New Zealand, containing questions pertaining to the demographics of respondents, their experience with DCO, what the expected risks and benefits of DCO would be, and provided two high-stress exemplar clinical scenarios where respondents were asked to rate their expected stress level at baseline, with a more junior consultant present, and with a more senior consultant present.

We found 99% of respondents had been involved in DCO at some point in their careers, yet only 38% were involved in DCO on at least a monthly basis. Perceived benefits greatly outweighed potential risks: 95% felt DCO would decrease their stress, 91% felt it improved intraoperative decision making, and 89% felt it provided more enjoyment at work and enhanced collegiality. A decrease in perceived stress was seen from baseline with a more junior consultant available and a greater decrease in stress seen with a more senior consultant, particularly in a complex elective setting.

All respondents felt there is benefit in DCO and the vast majority feel it has positive effects on stress levels. In a time where burnout is more prevalent, using tools such as DCO could be an effective way to decrease stress, enhance enjoyment and collegiality — challenging some key contributors to burnout — and support mentorship with further skill acquisition. This research provides a good base to pursue further qualitative and quantitative research into the area, with a view to addressing barriers to provision of regular DCO.

Aim

Prosthetic joint infections pose a major clinical challenge. Developing novel material surface technologies for orthopedic implants that prevent bacterial adhesion and biofilm formation is essential. Antimicrobial coatings applicable to articulating implant surfaces are limited, due to the articulation mechanics inducing wear, coating degradation, and toxic particle release. Noble metals are known for their antimicrobial activity and high mechanical strength and could be a viable coating alternative for orthopaedic implants [1]. In this study, the potential of thin platinum-based metal alloy coatings was developed, characterized, and tested on cytotoxicity and antibacterial properties.

Patients awaiting resolution of swelling and oedema prior to ankle surgery can represent a significant burden on hospital beds. Our study assessed whether external pneumatic intermittent compression (EPIC) can reduce delays to surgery.

Our prospective randomised controlled trial (n= 20) compared outcomes of patients treated with EPIC vs control group managed with ice and elevation. Included were patients aged <18 years with isolated closed ankle fractures admitted for management of swelling prior to surgery. Excluded were open fractures, injuries to contralateral leg, diabetes, absent pulses, peripheral vascular disease, inability to consent, no requirement for admission. Eligible patients were randomised to active or control arms. All patients were managed initially with reduction and back slab application. Patients in active arm fitted with EPIC (Hydroven 3000) device over the back slab. Assessment by treating team determined the time at which patient is assessed ready for surgery.

Patients in the treatment arm were assessed as ready for surgery sooner, (123 hrs vs 168hrs, T score = 1.925, P 0.035) and had a shorter time to surgery (167 hrs vs 216 hrs, T score = 1.748, P 0.047) Length of stay was reduced bud did not reach statistical significance. (259 hrs vs 269 hrs, T score 0.229, P 0.41)

Our results showed a statistically and clinically significant reduction in time that patients were assessed ready for surgery and time to surgery in the treatment cohort. We conclude that although further data is needed to achieve an adequately powered study and assess the safety profile of the EPIC, incorporation of EPIC into routine clinical practice has the potential for significant cost savings.

Proximal femoral focal deficiency is a congenital disorder of malformation of the proximal femur and/or the acetabulum. Patients present with limb length discrepancy and clinical features along a spectrum of severity. As these patients progress through to skeletal maturity and on to adulthood, altered biomechanical demands lead to progression of arthropathy in any joint within the lower limb. Abnormal anatomy presents a challenge to surgeons and conventional approaches and implants may not necessarily be applicable.

We present a case of a 62-year-old lady with unilateral proximal femoral focal deficiency (suspected Aitken Class A) who ambulated with an equinus prosthesis for her entire life. She presented with ipsilateral knee pain and instability due to knee arthritis but could not tolerate a total knee arthroplasty due to poor quadriceps control.

A custom osteointegration prosthesis was inserted with a view to converting to the proximal segment to a total hip replacement if required. The patient went on to develop ipsilateral symptomatic hip arthritis but altered acetabular anatomy required a custom tri-flange component (Ossis, Christchurch, New Zealand) and a custom proximal femoral component to link with the existing osseointegration component (Osseointegration Group of Australia, Sydney, Australia) were designed and implanted.

The 18 month follow up of the custom hip components showed that the patient had Oxford hip scores that were markedly improved from pre-operatively. Knee joint heights were successfully restored to equal when the patient's prosthesis was attached. The patient describes feeling like “a normal person”, walks unaided for short distances and can ambulate longer distances with crutches.

Advances in design and manufacture of implants have empowered surgeons to offer life improving treatments to patients with challenging anatomy. Using a custom acetabular tri-flange and osseointegration components is one possible solution to address symptomatic ipsilateral hip and knee arthropathy in the context of PFFD in adulthood.