Total hip arthroplasty (THA) is one of the most successful and effective treatments for advanced hip osteoarthritis (OA). Over the last 5 years, Canada has seen a 17.8% increase in the number of hip replacements performed annually, and that number is expected to grow along with the aging Canadian population. However, the rise in THA surgery is associated with an increased number of patients at risk for the development of an infection involving the joint prosthesis and adjacent deep tissue – periprosthetic joint infections (PJI). Despite improved hygiene protocols and novel surgical strategies, PJI remains a serious complication. No previous population-based studies has investigated PJI risk factors using a time-to-event approach and none have focused exclusively on patients undergoing THA for primary hip OA. The purpose of this study is to determine risk factors for PJI after primary THA for OA using a large population-based database collected over 15 years. Our secondary objective is to determine the incidence of PJI, the time to PJI following primary THA, and if PJI rates have changed in the past 15 years.

We performed a population-based cohort study using linked administrative databases in Ontario, Canada in accordance with RECORD and STROBE guidelines. All primary total hip replacements performed for osteoarthritis in patients aged 55 or older between January 1st 2002 – December 31st 2016 in Ontario, Canada were identified. Periprosthetic joint infection as the cause for revision surgery was identified with the International Classification of Diseases, 10th Edition (ICD-10), Clinical Modification diagnosis code T84.53 in any component of the healthcare data set.

Data were obtained from the Institute for Clinical Evaluative Sciences (ICES).

Demographic data and outcomes are summarized using descriptive statistics. We used a Cox proportional hazards model to analyze the effect of surgical factors and patient factors on the risk of developing PJI. Surgical factors include the approach, use of bone graft, use of cement, and the year of surgery. Patient factors include sex, age at surgery, income quintile and rurality (community vs. urban). We compared the 1,2,5 and 10 year PJI rates for patients undergoing THA each year of our cohort with the Cochran-Armitage test. Less than 0.1% of data were missing from all fields except for rurality which was lacking 0.3% of data.

A total of 100,674 patients aged 55 or older received a primary total hip arthroplasty for osteoarthritis from 2002–2016. We identified 1034 cases of revision surgery for prosthetic joint infection for an overall PJI rate of 1.03%. When accounting for patients censored at final follow-up, the cumulative incidence for PJI is 1.44%. Our Cox proportional hazards model revealed that male sex, Type II diabetes mellitus, discharge to convalescent care, and having both hips replaced during one's lifetime were associated with increased risk of developing PJI following primary THA. Importantly, the time adjusted risk for PJI was equal for patients operated within the past 5 years, 6–10 years ago, or 11–15 years ago. The surgical approach, use of bone grafting or cement were not associated with increased risk of infection. PJI rates have not changed significantly over the past 15 years. One, two, five and ten-year PJI rates were similar for patients undergoing THA in all qualifying years.

Analysis of a population-based cohort of 100,674 patients has shown that the risk of developing PJI following primary THA has not changed over 15 years. The surgical approach, use of bone grafting or cement were not associated with increased risk of infection. Male sex, Type II diabetes Mellitus and discharge to a rehab facility are associated with increased risk of PJI. As the risk of PJI has not changed in 15 years, an appropriately powered trial is warranted to determine interventions that can improve infection rate after THA.

Purpose: The popularity of intramedullary nails (IMN) for trochanteric hip fractures has grown substantially with little supportive evidence that IMN are superior to conventional sliding hip screws (SHS). We aimed to assess the impact of SHS or IMN intramedullary nailing on functional outcomes and rates of re-operation in elderly patients with fractures.

Method: We conducted a multi-center, pilot randomized trial including three clinical sites across Sweden, Denmark, and Canada. We randomized 85 elderly patients with stable and unstable trochanteric hip fractures to either SHS or an IMN. The primary outcome, revision surgery, was independently adjudicated at one year. Secondary functional outcomes included the Parker Mobility Score (PMS), the Merle D’Aubigne Score, the Short Form-12 (SF-12) and the Euroquol-5D.

Results: Eighty five patients were enrolled. Fifteen patients died prior to the one year follow up. Across treatment groups, patients did not differ in age, gender and fracture type. The overall revision risk was 11.6% (8/69) and did not differ significantly between groups (IMN: 5; SHS: 3). Patients treated with IMN had significantly higher Merle D’Aubigne function subscores at 6 (p=0.01) and 12 months (p=0.05). Gamma3 nails approached significantly higher scores in the Parker mobility score at 6 (p=0.08) and 12 months (p=0.056). Non-significant differences were identified in the SF-12 and Euroquol-5D quality of life measures; however, in both scores, the Gamma3 nailed trended to higher scores than the sliding hip screw.

Conclusion: Our findings of early functional gains without increased risk of revision surgery support the increased popularity of IMN for the management of trochanteric hip fractures in elderly patients.

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.

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.

Recent concerns regarding the prospective growth disruption of the olecranon apophysis in skeletally immature patients with intramedullary nail fixation for ulnar fractures has been documented. This retrospective review investigated the long-term functional and radiological outcomes of intramedullary nail fixation through the olecranon apophysis in skeletally immature patients.

Intramedullary nail fixation through the olecranon apophysis in skeletally immature patients is an effective, efficient procedure with excellent functional outcomes and without radiographic evidence of growth disruption at maturity.

To investigate the long-term radiological and functional outcomes on the olecranon apophysis after intra-medullary nail fixation in skeletally immature ulnar fractures.

Retrospective review of patients who where skeletally immature at the time of intramedullary nail fixation through the olecranon apophysis. Patients were excluded if they had previous forearms fractures or fracture of the contralateral forearm. Functional measures included the “Activities Scale for Kids (ASK)”, “Disabilities of the Arm, Shoulder and Hand (DASH)” and “Elbow Assessment Form (EAF)” questionnaires. Radiological outcomes where independently evaluated for ulnar, olecranon, coronoid and trochlear notch proportions at follow-up and initial post-op radiographic data. All patients had a clinical exam and the injured forearm outcomes were compared to the contralateral forearm.

Nineteen patients were assessed. The average age at surgical intervention was 10.8 years (range, 1.6–15.9) with a mean follow up time of 3.4 years (range, 1.2–7.2). We outlined the demographics, clinical outcomes and functional questionnaire outcomes for the study cohort. Detailed radiographic measurements for ulnar, olecranon, coronoid and trochlear notch proportions are outlined also.

Intramedullary nail fixation through the olecranon apophysis in skeletally immature patients is an effective, efficient procedure with excellent functional outcomes and without radiographic evidence of growth disruption at maturity. When skeletally immature ulnar fractures require an intramedullary nail fixation, disrupting the olecranon apophysis has not been shown to affect the long-term functional and radiological outcomes.

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