Introduction: We have described nine clinical features to aid the clinical diagnosis of frozen shoulder. These include symptoms of pain and pins and needles radiating down the arm to the hand, feeling of lameness in the arm, tenderness over medial border of scapula, tenderness over the rotator interval, tenderness over the brachial plexus in the supraclavicular fossa, reduction of pain with passive abduction and forward flexion of the shoulder, asymmetry of the arm position at rest with an increase in elbow to waist distance and apparent winging of the scapula.

Methods: We prospectively evaluate the sensitivity, specificity, predictive values and diagnostic accuracy of each clinical test in a consecutive series of 110 patients with idiopathic frozen shoulder. An equal number of patients with shoulder pathology other than frozen shoulder were used as controls matched to the study group for sex and age. We also discuss the probable causes and clinical relevance of these features.

Results The most sensitive test was pain over the brachial p:lexus in the supraclavicular fossa (0.98) and the most specific test was apparent winging of the scapula (0.84). The single most accurate diagnostic test was relief of symptoms with abduction and flexion (85%). The incidence of positive accessory features was positively correlated with the visual analogue pain score (p< 0.0001, Spearman rank correlation coefficient) and negatively correlated with the length of duration of symptoms (p< 0.0001, Spearman rank correlation coefficient).

Conclusion: These accessory tests are intended to supplement the original description made by Codman. They are most useful in the acute painful stage of the disease when symptoms have been present for less than 6 months. In the diagnosis of a patient with a painful stiff shoulder, if six of the tests with the highest correlation are positive, the diagnosis of frozen shoulder is likely.

To evaluate the mechanism by which orthopedic implant wear particles induce apoptosis in immature osteoblasts in an in-vitro setting.

Stromal cells from femurs of thirty day-old Swiss Webster Mice were isolated, cultured in-vitro, and incubated with orthopedic wear particles in the micrometer size range. After incubation with wear-particles, the cells were assessed for Caspase three expression and activity in the presence or absence of specific inhibitor(s) in order to delineate potential mechanism for cellular changes previously reported.

Here we report the induction of caspase three protein expression and activity with incubation of stromal cells with titanium wear particles. Caspase three activity however was not demonstrated to be up regulated in a time dependent manner or at lower concentration of particles (2 x 107 particles/ml). However, there was a significant (P< 0.05) increase in caspase three activity with titanium particle at higher concentration (4 x 107 particles/ml) that was not reversible when the extrinsic arm of the apoptotic pathway was blocked with anti-TNFƒa antibodies.

Our previous studies have suggested that aseptic loosening of orthopedic implants may be independent of inflammatory processes, and may be associated with induction of programmed cell death. Our current results would strengthen this idea by demonstrating induction of expression and activity of caspase three involved in apoptosis in cells incubated with wear particles. In addition, titanium wear particles may induce apoptosis through direct cellular effects rather than through the extrinsic TNFƒa pathway. Delineating the mechanism by which wear particles induce apoptosis in immature osteoblasts will allow for the selection and/or development of inhibitors to the process of asceptic loosening by targeting a specific pathway.

Introduction: A secure repair of the subscapularis represents an integral part of any surgery involving the anterior approach to the shoulder. Dysfunction of the subscapularis leads not only to poor functional results but also to anterior joint instability which is potentially untreatable. We have devised a new technique of double row fixation of the subscapularis using two suture anchors.

Aim: To evaluate the biomechanical strength of this double row technique against the established methods of simple suturing and transosseous repair techniques.

Method: Twenty matched pairs of human cadaveric shoulders were allocated into 3 groups. Group 1 consisted of 10 shoulders repaired with the double row technique. This involved incising the subscapularis along the bicipital groove and a lesser tuberosity osteotomy carried out leaving the subscapularis attached to a thin island of bone. A suture anchor (Twinfix) was then inserted just medial to the osteotomy site and the tendon repaired to bone using two horizontal mattress sutures. A second anchor was inserted laterally to supplement the repair with two simple suture knots. The remaining 10 contralateral shoulders were allocated equally between groups 2 and 3. In group 2, the subscapularis was divided longitudinally 1cm medial to the bicipital groove and repaired with simple interrupted suture knots. In group 3, the subscapularis was incised at its insertion to lesser tuberosity and the tendon repaired to the osteotomy site by multiple transosseous sutures through drill holes in the anterior humeral cortex.

The suture material used in all three groups was identical and consisted of an ultra high molecular weight poly-ethylene suture (Ultrabraid). To simulate the direction of pull of the subscapularis, the testing block was tilted 45 degrees while a vertically applied distraction force was applied. A custom made jig was used to measure the amount of displacement in response to a gradually applied load. All specimens were tested to failure. The mode of failure of each fixational construct was recorded.

Results: The load to failure was found to be significantly higher in the double row repair technique compared to simple suturing and transosseous methods. Simple suturing failed by suture cutting out of soft tissue and tranosseous repair failed by a combination of the suture cutting out through bone and soft tissue.

Conclusion: This new double row technique is simple to perform and preliminary biomechanical testing has shown this to be superior in terms of fixational strength compared to established methods. Additional advantages of this technique which have not been taken into account in this in vitro study include non violation of the subscapularis tendon with bone to bone healing.

As a result of the increased popularity of metal-on-metal bearings for total hip arthroplasty, concerns have been expressed about patient exposure to increased serum metal ion levels.

We therefore performed a retrospective review of patients with metal-on-metal, uncemented Ring total hip replacements with a minimum follow up of thirty years.

After allowing for prosthesis revision and patient mortality, 6 hips in 5 patients were reviewed and serum ion levels measured. Similar cohorts of patients with other combinations of bearings were compared with an age-matched osteoarthritic control group.

Serum cobalt and chromium levels in the metal-on-metal hip arthroplasty group were significantly higher than in all other groups and approximately five and three times greater respectively than in the group with no implants. Unlike the stainless steel-on-plastic group, the cobalt/chrome-on-plastic group showed significantly raised serum cobalt levels compared with the control group. It is of interest that patients who have had their metal-on-metal hip replacements revised to metal-on-plastic, have metal ion levels that are not statistically different to those of the osteoarthritic control group.

Though we acknowledge the small numbers of patients studied, no identifiable harmful effects were found.

We conclude that serum metal ions remain elevated throughout the life of the metal-on-metal articulation. Metal bearing hip arthroplasty is being used in ever younger patients and together with increased life expectancy we are exposing our patients to potentially harmful levels of metal ions throughout the life of the implant.

The management of bony lesions associated with glenohumeral instability has been open to debate. Invariably a significant period of time elapses between injury and surgery during which the bony fragment may atrophy and reduce both in size and in quality. Histomorphometric bone analyses were prospectively performed on the glenoid bone fragments harvested during the modified Latarjet operation. The main purpose of the study was to assess the viability of the bone. Biopsies were obtained from 21 patients that had given informed consent. Median age was 21 years (range 16–50). All were male patients. The most important sports identified were rugby (64%) and water sports (surfing, water polo, water skiing, surfing (21%)). Mean glenoid bone loss on CT scan was 17% (range 10–50%). Thirty-three percent had bone loss greater than 20%. Gross morphology of glenolabral fragments identified a single large fragment (11/21); dominant large fragment plus smaller fragments (7/21); multiple fragments (4/21). Single large fragments comprised 52% of the study. Mean volume and mass of bony fragments were 2.18 ml (range 1–3 ml) and 1.64 gms (range 0.43–2.8 g), respectively. Histology of the specimens revealed no bone in three of the 21 specimens. Bony necrosis was present in 8/18 (44%) of the specimens. From a histopathological point of view, reattachment of these devitalized bone fragments by screws or anchors may result in predictable operative failure and recurrent instability. We can therefore not support the practice of “repair” of bony Bankart lesions based on the above findings.

A ligament tensioning device was used during total knee arthroplasty procedures to determine the effective stiffness of the soft tissue envelope around osteoarthritic knees. This information was used to calculate the resting forces on polyethylene components in well balanced knees. Various patient and implant factors were investigated to see if they correlated with the stiffness of the soft tissues around arthritic knees. The effective stiffness of the soft tissues was found to be higher when the posterior cruciate ligament was preserved compared to when it was sacrificed.

The purpose of this study was to determine, in vivo, the effective stiffness of the soft tissue envelope around the knee and to estimate the resting force on the implanted polyethylene component during total knee arthroplasty (TKA). A ligament tensioning device was used to measure displacement between the tibia and the femur versus load during eighty-six consecutive TKA procedures. A maximum of five measurements were made in both flexion and extension. The measurements were taken after bone cuts were made and soft tissue balancing was performed. The effective stiffness of the knee soft tissue envelope was determined in flexion and extension. Post- operative range of motion was measured while the patient was still under anesthetic. There was no significant difference in the average effective stiffness between men and women or between flex-ion and extension. Age did not appear to correlate with effective stiffness. The average effective stiffness was significantly higher in posterior cruciate retaining knees compared to those in which the posterior cruciate was sacrificed. There was no statistical significance between the average resting force on the polyethylene in men versus women, in flexion versus extension, or in posterior cruciate retaining knees versus posterior cruciate sacrificing knees. The immediate post-operative range of motion did not correlate with the resting force on the implanted polyethylene

Purpose: The purpose of this study was to determine how to minimize intramedullary femur pressures, and therefore the risk of fat embolus syndrome, during surgical procedures which require preparation and instrumentation of the femoral canal.

Methods: To study intramedullary femur pressures and experimental model and a finite element model were developed. The experimental model ustilized a bone analogue which consisted of a porous plastic cylinder, having similar porosity and pore size to human femoral bone, with bone marrow being represented by a paraffin wax/petroleum jelly mixture. The finite element model consisted of a three dimensional analysis of a cylinder filled with bone marrow with a reamer advancing through it. Variables such as speed of insertion, fluid viscosity and relative diameters of the instrument and the inner diameter of the simulated bone were varied to see how they affected pressures.

Results: The intramedullary pressures increased with increasing speed of instrument insertion, increasing marrow viscosity, and increased diameter of the instrument relative to the inner diameter of the bone. Experimental and finite element results were in reasonable agreement.

Conclusions: We concluded that slower instrument insertion rates and a greater ratio of bone inner diameter to instrument diameter may minimize the intramedullary pressures and therefore minimize the risk of fat embolus syndrome. In addition, two novel techniques to analyze intramedullary femur pressures have been developed.

Funding : Education Grant

Funding Parties : NSERC

Retrospective analysis of three hundred and seventy-one obese (BMI _ 30) and two hundred and forty-nine non-obese (BMI < 30) primary unilateral TKA patients with minimum one-year follow-up to determine influence of obesity versus non-obesity on clinical outcomes following primary unilateral total knee arthroplasty (TKA) for osteoarthritis. Obese patients fare just as well as non-obese patients, experiencing a greater degree of improvement in observed and self-reported outcome measures.

Multiple factors determine outcome of TKA. This study aimed to determine influence of obesity versus non-obesity, as measured by body mass index (BMI), on clinical outcomes following primary unilateral total knee arthroplasty (TKA) for osteoarthritis. Compared to non-obese patients, obese patients had inferior preoperative clinical scores, but achieved comparable ultimate clinical outcomes.

Despite inferior preoperative clinical scores, obese patients undergoing primary TKA for osteoarthritis can expect the same ultimate clinical outcome as non-obese patients.

Statistically significant differences for; mean age of obese 69.2 ±9 and non-obese 73±8 (p< 0.0001), with a higher preponderance of obese females, 70.2% vs. 30% male (p=0.033).

Despite statistically significant differences among all preoperative clinical outcomes including; KSS clinical (p=0.019), KSS function (p=0.02), Oxford (p=0.02), and flexion (p=0.001), there were no statistically significant differences among these outcomes at one-year postoperative. No statistical difference among surgical outcomes, hospital length of stay, pain scores or stair climbing ability at any interval.

Retrospective analysis of three hundred and seventy-one obese (BMI _ 30) and two hundred and forty-nine non-obese (BMI < 30) primary unilateral TKA patients with minimum one-year follow-up. Statistical analysis to determine differences in demographics, surgical time, intraoperative complications, hospital length of stay, and clinical outcomes including; flexion, KSS and Oxford score, pain-level and stair climbing ability at six-week, six-month, and one-year postoperative. Patients with previous high tibial osteotomy, ORIF, or receiving associated WSIB benefits were excluded.

Obese patients fare just as well as non-obese patients, experiencing a greater degree of improvement in observed and self-reported outcome measures.

To evaluate the effect of implant articular geometry on postoperative range of motion (ROM) after primary total knee arthroplasty for osteoarthritis, we conducted a retrospective case-control study of one hundred and twenty patients (sixty in each group) comparing Scorpio® Posterior Cruciate Substituting implant using Superflex® versus traditional tibial insert. Cases and controls were matched 1:1 for surgeon and gender. Both groups had similar baseline characteristics. Except for KSS Clinical Score at six months (mean: 92.8 for Superflex® versus 87.6 for traditional insert; p=0.029), there was no statistically significant difference between the two groups in knee scores or ROM up to one-year postoperatively.

To evaluate the effect of implant articular geometry on postoperative range of motion (ROM) after primary TKA.

Despite the advent of high flexion knee designs, surgical technique and patient driven factors remain the overriding determining factors for ultimate flexion range achieved following TKA.

One hundred and twenty patients (sixty in each group) were included. Both groups had similar baseline characteristics. Except for KSS Clinical Score at 6 month (mean ± SD: 92.8 ± 5.8 for Superflex® versus 87.6 ± 14.6 for traditional insert; p=0.029), there was no statistically significant difference between the two groups in knee scores or ROM. Flexion at one year for Superflex® was 113.5° ± 10.5 compared with 113.2° ± 11.9 for traditional tibial insert (p=0.869).

Retrospective cohort study of a prospectively gathered database of TKA’s performed at a high-volume arthroplasty center from 1998 to 2003. Inclusion Criteria: primary TKA for osteoarthritis using Scorpio® Posterior Cruciate Substituting implant with Superflex® tibial insert versus traditional insert. Exclusion Criteria: WSIB, prior history of septic arthritis, and previous knee surgery. Cases and controls were matched 1:1 for surgeon and gender. Postoperative care was standardized. Data points included demographics, operative details, pre- and post-operative Knee Society Score (KSS), Oxford Knee Score and range of motion at six weeks, six months and one year postoperatively. P< 0.05 was considered statistically significant.

Despite improvements in knee prostheses design, patient factors and surgical technique remain the most important determinants of outcome in primary TKA, particularly ROM.

Retrospective review of four thousand two hundred and fifty-two patients undergoing TJR at a single high-volume arthroplasty centre to determine prevalence and timing of myocardial infarction (MI) following TJR. The incidence of peri-operative MI was 1.5%, with a mean of three days to time of MI. This cohort was comprised of 55% females with a mean age of seventy-five years. We found poor correlation between pre-operative risk assessment using the Modified Multifactorial Index score. Our findings suggest that there is a minimum length of stay compatible with patient safety given the inadequacy of currently available preoperative risk assessment tools.

This study was undertaken to evaluate the prevalence and timing of peri-operative myocardial infarction in patients undergoing total joint replacement (TJR).

Despite the pressure toward decreasing length of stay following TJR surgery, we suggest that there is a minimum length of stay compatible with patient safety given the inadequacy of currently available preoperative risk assessment tools.

The prevalence rate of peri-operative MI was 63/4252(1.5%), with a mean time of three days (range 0–18) to MI. Furthermore, there was a predominance of females (55%) and a mean age of seventy-five years among this cohort. We found poor correlation between pre-operative risk assessment using the Modified Multifactorial Index score.

Patients who suffered an acute MI following elective TJR surgery between April 1998 and April 2003 were abstracted from the Hospital CIHI database of four thousand two hundred and fifty-two patients. The role of preoperative risk assessment and risk reduction strategies were also evaluated.

The previously reported rate of MI is 0.3 % and 0.9% following unilateral and bilateral TJR respectively. The reported frequency of MI tends to increase with older age (> 70 yrs) and male gender. There is emerging information that these rates may be grossly under-estimated. Prosthetic arthroplasty is major surgery and regardless of the surgical technique, patients remain at risk for complications.

Historically, cemented THA femoral stems inserted in varus have yielded poor clinical results. Very few studies to date have addressed the question of the effects of varus alignment on uncemented stems. We have conducted a retrospective review of one hundred and twenty-five uncemented THA femoral stems implanted by a single surgeon from 1994 to 1999. Within this single surgeon group we were able to identify sixteen stems implanted in varus and thus proceeded to analyze the effect of varus alignment on functional outcome.

To assess functional and radiographic outcome of uncemented primary THA femoral stems implanted in varus.

After four-years of follow-up, there have been no radiographic or clinical problems associated with implanting uncemented femoral stems in varus.

Although it is not recommended to implant stems in varus, radiographic and clinical problems associated with implanting uncemented femoral stems in varus appear to be non-consequential.

Of the study sample, one hundred and sixteen hips were in neutral alignment as compared to sixteen varus hips. We could not show any significant difference in Harris Hip scores between the varus and non-varus hips (p> 0.5). No cases showed evidence of radiographic loosening, or subsidence (p=0.3) at four-year follow-up.

Retrospective radiographic review of one hundred and twenty-five uncemented primary THA femoral stems implanted by a single surgeon (now retired) from 1994 to 1999, using the Watson-Jones approach, identified sixteen femoral stems implanted in varus. These sixteen stems were matched 1:1 for demographics and preoperative diagnosis to a cohort of sixteen non-varus uncemented stems implanted by the same surgeon over the same study period. Functional outcome included Harris Hip score and range of motion at four-years postoperative. Radiographic signs of loosening and subsidence, defined as > 2mm, were measured. Varus alignment was defined as ≥ 5°. Paired t-tests were conducted on all outcome variables, p< 0.05 was considered statistically significant.

Study results suggest there to be no consequence of varus femoral alignment in uncemented stems. Patients will need to be followed for a longer duration to further examine the effects of varus implantation of unce-mented femoral stems.

Purpose: Peri-implant osteolysis after total joint arhtro-plasty (TJA) is a major cause of implant loosening. Cellular responses to wear particles have been reported to play a role in asceptic loosening due to their cytotoxic nature to cellular components. Purpose of this study is to evaluate the effect of orthopedic implant wear particles on immature osteoblasts in an in-vitro setting in order to further understand the mechanisms involved in asceptic loosening of implants.

Methods: Stromal cells from femurs of 30 day-old Swiss Webster Mice were isolated, cultured in-vitro, and incubated with Titanium and Ceramic (smooth and angular) particles in the micrometer size range. After 9 days of incubation the cells were assessed for Alkaline phosphatase (ALP) activity or stained for cellular changes consistent with apoptosis.

Results: Here we report both a dose-dependent decrease (P< 0.05) in ALP activity and a significant increase in programmed cell death when murine stromal cells were cultured with orthopedic implant wear particles of differing compositions. Ceramic wear particles were consistently less toxic at lower concentrations (1 x 107 to 2 x 107 particles/ml) than were wear particles composed of titanium. However, at high concentrations (4 x 107 particles/ml) all particles regardless of composition were equally toxic. These findings suggest that ceramic particles may be less cytotoxic to bone marrow stromal cells/osteoblasts than are titanium particles.

Conclusions: Previous studies have suggested that inflammatory responses to orthopedic wear particles are responsible for the asceptic loosening of orthopedic implants. In the current study however, we found that wear particles may also induce cellular apoptosis of primary bone forming cells. This suggests that the asceptic loosening of orthopedic implants may be independent of inflammatory processes, and that implant material selection should be directed, in part, by its inability to cause programmed cell death.

Purpose: Our purpose was to evaluate why some patients achieve excellent range of motion (ROM) following total knee arthroplasty (TKA) and to determine its relation to outcome.

Methods: We evaluated 618 primary unilateral TKA’s for osteoarthritis from a prospective arthroplasty database using a single implant design. 209 TKA’s with ROM greater than 120 degrees at one year follow-up were compared to 409 TKA’s with ROM less than 120 degrees to determine if age, BMI, gender, ASA class, and preop ROM differed between the two groups. Knee society and oxford knee scores were also compared both preoperatively and at one year follow-up using independent samples t-test. A multiple logistical regression analysis was performed to determine predictors of ROM.

Results: Preoperative ROM was higher (115 vs 106, p< 0.0001), BMI was lower (30.7 vs 32.9. p< 0.0001), and there was a higher proportion of males (p< 0.0001) in those patients with exceptional ROM at one year (> 120 degrees). Knee Society Score (93.7 vs 87.8, p< 0.0001) and Oxford Knee Score (20.4 vs 24.4, p< 0.0001) were superior in the exceptional ROM group at one year follow-up. In multiple logistic regression, only preoperative ROM (p< 0.0001) was a significant predictor of postoperative flexion range.

Conclusions: Body habitus may play a role in our ability to achieve exceptional flexion following TKA. Implant design has historically favoured male anatomy which may influence exceptional flexion range. Preoperative ROM still seems to be the biggest predictor of postoperative ROM. Perhaps timely surgical intervention, pre-habilitation and implant design choice can influence our ability to achieve exceptional ROM following TKA.

A prospective evaluation was undertaken utilizing the SF12 score, Oxford Knee score, Knee Society Score (KSS), visual analog pain score, and a non-validated questionnaire to determine patient self-perception of leg alignment after knee arthroplasty, and impact of satisfaction with alignment on clinical outcomes. 21/84 (25%) patients were dissatisfied with their new leg alignment and this group subsequently reported greater pain scores (p< 0.001) and lower SF12 scores (p< 0.002). Oxford Scores and KSS showed no difference between groups. We suggest that patient satisfaction with postoperative lower extremity alignment is an important issue affecting subjective outcomes in total knee arthroplasty (TKA).

This study was undertaken to determine how patients perceive their leg alignment after knee arthroplasty and whether their level of satisfaction with alignment affects clinical outcomes.

The results of this study suggest that there may be some benefit to preoperative counselling on what to expect in regard to leg alignment following surgery. Additionally, given the adverse impact of dissatisfaction with limb alignment on subjective outcomes, we suggest that patient satisfaction regarding leg alignment should be considered for inclusion in the design of subjective outcomes measures for total knee arthroplasty.

21/84(25%) patients were dissatisfied with their new leg alignment while all but one had an anatomic axis between 4–100 valgus radiographically. This group subsequently reported greater pain scores (p< 0.001) and lower SF12 scores (p< 0.002). At six months follow-up, there was no difference between groups on the Oxford Knee or KSS (p> 0.05).

A non-validated questionnaire was utilized to prospectively ask patients to self-rate their alignment, their satisfaction with their alignment, and their pain scores on a visual analog scale (VAS). Additional outcome measures included pre and postoperative SF-12, Oxford Knee and KSS.

There is still no consensus regarding any one single scoring system with regard to clinical outcomes of primary TKA. Also, it has been widely reported that surgeons often perceive outcomes of TKA with more success than patients. 21/84 of our patients were dis-satisfied with their alignment while all but one had an anatomic axis between 4–100 valgus radiographically.

It is known that activity level correlates with wear in total joint arthroplasty. UCLA activity score surveys were sent to four hundred and sixty-seven knee and hip arthroplasty patients with good/excellent clinical outcomes as determined by one-year postoperative Knee Society (KSS) and Harris Hip (HHS) scores. The UCLA activity score was correlated with clinical outcomes and demographic data. Average UCLA score was 6.2 for hips, 6.3 for knees, indicating moderate activity levels. Hip arthroplasty UCLA score significantly correlated with age, gender and one-year Oxford score. Knee arthroplasty UCLA score significantly correlated with gender, one-year functional KSS and Oxford score.

Arthroplasty patients are often warned to avoid high level activities for fear of implant loosening, failure or increased polyethylene wear. Patients with good/excellent clinical outcomes may however be inclined to participate in higher demand activities. There is need for specific information regarding patient profile and activity level following TJR.

Current recommendations for activity among TJR patients may not be justified. Longer-term follow-up will elucidate specific activities which may be permissible or detrimental to implant survivorship.

Survey response rate was 70.2% among THA patients at mean 40.7months. Mean UCLA score was 6.2/10, indicating moderate activity. Mean outcome scores; one-year HHS 94.8, Oxford 6.6. UCLA score significantly correlated with age, gender and one-year Oxford.

Survey response rate was 81.8% among TKA patients at mean 36.6months. Mean UCLA score was 6.3/10, indicating moderate activity. Mean outcome scores; one-year KSS clinical 95.9, KSS function 95, Oxford 18.2. UCLA score significantly correlated with gender, one-year KSS function and Oxford.

No significant differences among clinical outcomes and survey non-respondents.

UCLA activity score survey of two hundred and twenty-five primary TKA and two hundred and forty-two primary THA patients. Patients abstracted from prospective database and pre-selected for good/excellent outcomes based on KSS and HHS at one-year. Clinical outcomes included Oxford Hip/Knee scores. UCLA, demographics and clinical outcomes correlated using Pearson’s correlation.

UCLA scores indicate the average TJR patient maintains a moderate activity level. Younger male patients with low Oxford can be expected to participate in higher level activities. One THA patient underwent subsequent revision despite moderate activity level.

A radiographic review of sixty-nine lateral closing wedge high tibial osteotomies and forty-two medial opening wedge osteotomies was conducted. Patellar height and tibial slope were measured. The Blackburne-Peel (BP) and Insall-Salvati (IS) ratios were used to measure patellar height. Our results show that 18.8% and 47.6% of the lateral closing wedge group had patella-infera (PI) according the the BP and IS ratios respectively. No opening-wedge cases demonstrated patella infera with either ratio. Tibial slope was found to be significantly more neutral in the closing wedge group versus the opening wedge (−2.2° vs. −7.28° respectively).

Patients undergoing HTO typically require a definitive arthroplasty procedure at an average of six years post-HTO. Total knee arthroplasty can be complicated by the presence of PI which compromises exposure and increases the risk of patellar tendon avulsion leading to suboptimal results. The current study compares the incidence of PI between lateral closing and medial opening wedge HTO’s.

Conversion of opening wedge HTO to TKA should have less technical challenge and improved outcomes as compared to lateral closing wedge HTO conversions. This is attributable to the absence of PI.

Of the closing wedge group, 18.8% and 47.6% were found to have PI according to the BP and IS ratios respectively. Of the opening wedge group there were no cases of PI found with either ratio. Tibial slope was found to be significantly more neutral in the closing wedge compared to the opening wedge group (−2.2° vs. −7.28° respectively).

The study cohorts were abstracted from surgeon records. Sixty-nine closing wedge and forty-two opening wedge HTO’s were identified. Lateral 30° flexion x-rays were measured for patellar height and tibial slope. Both the Blackburne-Peel (BP) and Insall-Salvati (IS) patellar height measurements were used.

From this data we can conclude that in our study population the incidence of PI in the opening wedge group was 0% thus negating the potential deleterious effects of PI at the time of knee arthroplasty.

A retrospective review was conducted to evaluate short-term (one year) outcomes of primary total knee arthroplasty (TKA) patients receiving Ontario Worker’s Safety and Insurance Board Benefits (WSIB) compared to a matched cohort of non-WSIB patients. Postoperatively, WSIB patients had higher pain scores, poorer self-perceived functional outcomes and lower flexion range. WSIB patients required more postoperative clinic visits and were more reluctant to answer questions regarding functional outcome. All differences were statistically significant. The short-term outcomes of primary TKA in patients receiving WSIB benefits are inferior to those obtained by non-WSIB patients.

Retrospective review to evaluate short-term outcomes of primary TKA patients receiving WSIB as compared to non-WSIB patients.

Short-term outcomes of primary TKA in WSIB patients are inferior both subjectively and objectively to non-WSIB patients. WSIB patients are seen more frequently for postoperative follow-up which we would attribute to the persistence of subjective complaints following primary TKA.

Short-term outcomes of primary TKA in WSIB patients are inferior to those obtained by non-WSIB patients. WSIB patients undergoing primary TKA require more postoperative visits with a greater prevalence of subjective postoperative complaints.

Thirty-eight WSIB patients who underwent primary TKA were matched to thirty-eight non-WSIB patients. There were no statistical differences in preoperative Knee Society (KSS) and Oxford Score. Six-week total KSS (p=0.011), pain as measured by KSS (p=0.015), and flexion (p=0.012) were significantly different between the groups. At six-months similar results were noted among KSS function (p=0.027) and pain (p=0.024), Oxford Score (p=0.027), and flexion (p=0.035). One-year Oxford Score (p=.011) and flexion (p=0.013) were statistically significant, as were the McGrory Modified Knee Score (p=0.001), patient expectations (p=0.030), perceived quality of life (p=0.009), and number of postoperative clinic visits (p=0.024).

Retrospective review on successive WSIB patients undergoing primary TKA, at a single arthroplasty centre, matched to a cohort of non-WSIB patients for demographics and preoperative diagnosis. Outcomes included Knee Society, Oxford Knee, and McGrory et al Modified Knee scores, patient satisfaction, and number of postoperative clinic visits. Unpaired t-tests were used to determine differences in outcomes.

There are few reports but many allusions regarding inferior outcomes of TKA in WSIB patients. Our study provides further evidence to support this view. Multiple factors may account for this variance, including psychosocial factors. Further prospective studies are needed to address this burgeoning issue.

Metal-on-metal bearings for total hip replacement (THR) are becoming increasingly popular. Improved wear characteristics mean that these articulations are being inserted into younger patients in the form of THR and resurfacing procedures. This has led to concerns regarding potential carcinogenicity because of the increased exposure to metal ions that the procedure brings.

We have studied the serum cobalt and chromium concentrations in patients who had primary, well-fixed Ring metal-on-metal THRs for more than 30 years. The levels of cobalt and chromium were elevated by five and three times, respectively compared with those in our reference groups. Metal-on-metal articulations appear to be the source of metal ions throughout the life of the prosthesis. In three patients who had undergone revision of a previous metal-on-metal THR to a metal-on-polyethylene replacement the levels of metal ions were within the normal range. The elevations of cobalt and chromium ions seen in our study were comparable with those in patients with modern metal-on-metal THRs.

Treatment of OA of the shoulder in young and active patients remains a problem. Present treatment options are debridement, microfracturing, arthrodesis or shoulder replacement. We report the preliminary results of soft-tissue interposition arthroplasty with an acellular allograft skin-derived collagen matrix (Graft Jacket®, Wright Medical).

Between July and December 2003 five men and one woman with severe glenohumeral OA had a soft-tissue interposition arthroplasty of the shoulder. The mean age of the patients was 47 years (34 to 58). In four patients the procedure was done arthroscopically. The Graft Jacket® was sutured to the labrum with a minimum of five sutures. The mean postoperative follow-up was 6.2 months.

Four patients experienced notable pain relief after the operation. Preoperatively the mean visual analogue pain score was 7.2 and postoperatively it was 2.6. One patient had no improvement and elected to wait before having further treatment. One patient needed a hemi-arthroplasty. The range of motion improved in only one patient. The mean Constant score improved 14 points, from 45 to 59. There were no complications peroperatively or postoperatively.

While the long-term results are still unknown, soft-tissue interposition arthroplasty with the Graft Jacket® shows promising results.

External rotation of the shoulder is commonly measured in two ways, with the arm adducted or with the arm abducted to 90°. The measurement forms an important part of the assessment of shoulder function, but has been shown to be unreliable. Following the observation that, with the arm adducted, the range of external rotation alters according to the exact position of the arm in the sagittal plane, we conducted a study to quantify the effect on the range of external rotation of a small increment in forward flexion (15°).

With the arm first in a vertical position and then in 15° of forward flexion, external rotation was measured in 40 asymptomatic and 20 ‘frozen’ shoulders. With forward flexion, the range of external rotation decreased by a mean of 16.9° in the asymptomatic and 13.5° in the ‘frozen’ shoulders.

We postulate that some of the variation is a function of scapular positioning. With arm flexion, the scapula protracts, resulting in alteration in glenoid version. However, some difference is due also to alteration in soft tissue tension in the two arm positions.

The sagittal position of the arm affects the range of external rotation of the adducted shoulder. This variation in measurement may affect the scores of certain outcome measures.