Etienne L. Belzile

Comparison of whole-blood metal ion levels in four types of metal-on-metal large-diameter femoral head total hip arthroplasty: the potential influence of the adapter sleeve.

BACKGROUND Metal-on-metal bearings, as used in total hip arthroplasty prostheses that have a large-diameter femoral head, were proposed as an option for treating young and active patients with degenerative hip disorders. Despite the theoretical improved performance of large metal articulations with regard to wear, metal ion levels produced by total hip arthroplasty prostheses in which a large-diameter femoral head is used have not been thoroughly evaluated. METHODS From 173 eligible patients, 144 patients were allocated to undergo a unilateral total hip arthroplasty with use of metal-on-metal components and a large-diameter femoral head. The purpose of this study was to compare the amount of metal ion release (chromium, cobalt, and titanium) from four different types of prostheses from four different implant manufacturers (Biomet, DePuy, Smith & Nephew, and Zimmer). RESULTS For cobalt ion levels, a significant difference was found between the different types of total hip arthroplasty prostheses with a large-diameter femoral head at three, six, twelve, and twenty-four months, but only in male patients or patients with a femoral head size of 50 mm or greater. The highest mean cobalt levels at all follow-up periods were observed with the Zimmer implant and the lowest with the Biomet implant. Titanium ion levels were highest in the Zimmer group at all follow-up periods, whereas no difference between groups was found for chromium. At the most recent follow-up, one hip was revised after the development of an adverse local tissue reaction. Of concern was the observation at the time of revision surgery of black metallic deposits inside the adapter sleeve and on the prosthetic femoral neck. CONCLUSIONS This investigation revealed that metal ion release differs greatly between various total hip arthroplasty implants with a large-diameter femoral head. The sources of metal ion production are numerous, but it is hypothesized that wear and corrosion at the junction between the adapter sleeve and the femoral stem in some patients may be responsible for the elevated cobalt ion levels that were found in the Zimmer group. On the other hand, an adapter sleeve made of titanium, such as the one used with the Biomet large-diameter-head total hip arthroplasty, is an unlikely contributor to the release of cobalt ions. Current technology or design of some total hip arthroplasty systems that make use of a large-diameter femoral head may not yet allow the use of modular large heads with a metal-on-metal articulation, especially in young, active male patients whose activities generate high loads at the hip joint. Further research is needed to better understand the favorable design characteristics of modular junctions in metal-on-metal total hip arthroplasty implants that make use of large-diameter femoral heads.

Aspirin versus low-molecular-weight heparin for extended venous thromboembolism prophylaxis after total hip arthroplasty: a randomized trial.

BACKGROUND The role of aspirin in thromboprophylaxis after total hip arthroplasty (THA) is controversial. OBJECTIVE To compare extended prophylaxis with aspirin and dalteparin for prevention of symptomatic venous thromboembolism (VTE) after THA. DESIGN Multicenter randomized, controlled trial with a noninferiority design based on a minimal clinically important difference of 2.0%. Randomization was electronically generated; patients were assigned to a treatment group through a Web-based program. Patients, physicians, study coordinators, health care team members, outcome adjudicators, and data analysts were blinded to interventions. (Current Controlled Trials: ISRCTN11902170). SETTING 12 tertiary care orthopedic referral centers in Canada. PATIENTS 778 patients who had elective unilateral THA between 2007 and 2010. INTERVENTION After an initial 10 days of dalteparin prophylaxis after elective THA, patients were randomly assigned to 28 days of dalteparin (n = 400) or aspirin (n = 386). MEASUREMENTS Symptomatic VTE confirmed by objective testing (primary efficacy outcome) and bleeding. RESULTS Five of 398 patients (1.3%) randomly assigned to dalteparin and 1 of 380 (0.3%) randomly assigned to aspirin had VTE (absolute difference, 1.0 percentage point [95% CI, -0.5 to 2.5 percentage points]). Aspirin was noninferior (P < 0.001) but not superior (P = 0.22) to dalteparin. Clinically significant bleeding occurred in 5 patients (1.3%) receiving dalteparin and 2 (0.5%) receiving aspirin. The absolute between-group difference in a composite of all VTE and clinically significant bleeding events was 1.7 percentage points (CI, -0.3 to 3.8 percentage points; P = 0.091) in favor of aspirin. LIMITATION The study was halted prematurely because of difficulty with patient recruitment. CONCLUSION Extended prophylaxis for 28 days with aspirin was noninferior to and as safe as dalteparin for the prevention of VTE after THA in patients who initially received dalteparin for 10 days. Given its low cost and greater convenience, aspirin may be considered a reasonable alternative for extended thromboprophylaxis after THA. PRIMARY FUNDING SOURCE Canadian Institutes of Health Research.

In-Home Telerehabilitation Compared with Face-to-Face Rehabilitation After Total Knee Arthroplasty: A Noninferiority Randomized Controlled Trial.

BACKGROUND The availability of less resource-intensive alternatives to home visits for rehabilitation following orthopaedic surgeries is important, given the increasing need for home care services and the shortage of health resources. The goal of this trial was to determine whether an in-home telerehabilitation program is not clinically inferior to a face-to-face home visit approach (standard care) after hospital discharge of patients following a total knee arthroplasty. METHODS Two hundred and five patients who had a total knee arthroplasty were randomized before hospital discharge to the telerehabilitation group or the face-to-face home visit group. Both groups received the same rehabilitation intervention for two months after hospital discharge. Patients were evaluated at baseline (before total knee arthroplasty), immediately after the rehabilitation intervention (two months after discharge), and two months later (four months after discharge). The primary outcome measure was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire at the last follow-up evaluation. Secondary outcome measures included the Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaire, functional and strength tests, and knee range of motion. The noninferiority margin was set at 9% for the WOMAC. RESULTS The demographic and clinical characteristics of the two groups of patients were similar at baseline. At the last follow-up evaluation, the mean differences between the groups with regard to the WOMAC gains, adjusted for baseline values, were near zero (for 182 patients in the per-protocol analysis): -1.6% (95% confidence interval [CI]: -5.6%, 2.3%) for the total score, -1.6% (95% CI: -5.9%, 2.8%) for pain, -0.7% (95% CI: -6.8%, 5.4%) for stiffness, and -1.8% (95% CI: -5.9%, 2.3%) for function. The confidence intervals were all within the predetermined zone of noninferiority. The secondary outcomes had similar results, as did the intention-to-treat analysis, which was conducted afterward for 198 patients. CONCLUSIONS Our results demonstrated the noninferiority of in-home telerehabilitation and support its use as an effective alternative to face-to-face service delivery after hospital discharge of patients following a total knee arthroplasty. LEVEL OF EVIDENCE Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

The burden of wait for knee replacement surgery: effects on pain, function and health-related quality of life at the time of surgery

OBJECTIVE To examine the change in pain and function related to the knee scheduled for surgery, change in health-related quality of life (HRQoL) and change in contralateral knee pain during pre-surgery wait up until time of surgery. METHODS One hundred and fifty-three patients scheduled for knee replacement were recruited from three hospitals in Québec City, Canada, and followed until surgery. Pre-surgery wait, defined as the time between enrolment on the pre-surgery wait list and surgery, was considered in five categories (< or =3, >3-6, >6-9, >9-12 and >12 months). Pain and functional limitations were measured with the Western Ontario and McMaster Osteoarthritis Index (WOMAC) and HRQoL was measured with the medical outcomes study 36-item short form health survey. RESULTS Mean pre-surgery wait time was 183 (s.d. 121.9) days. Subjects having waited >9-12 months showed significant deterioration of the WOMAC pain (-9.9; 95% CI -19.2, -0.54) and function (-11.1; 95% CI -18.7, -3.4) scores. On the HRQoL SF-36 physical functioning scale, a significant deterioration was seen in subjects having waited >9-12 months (-11.3; 95% CI -18.4, -4.2) and >12 months (-7.1; 95% CI -12.9, -1.3). On the contralateral knee WOMAC pain score, a significant deterioration was observed in subjects having waited >6-9 months (-10.4; 95% CI -16.9, -3.9) and >12 months (-10.7; 95% CI -19.7, -1.7). CONCLUSION Pre-surgery wait time has a negative significant impact on pain, function and HRQoL at the time of surgery. The magnitude of deterioration seen in this study may be clinically important. The effects of this pre-surgery deterioration on post-surgery outcomes need to be investigated.

A prospective randomized multicenter trial comparing clinical outcomes of patients treated surgically with a static or dynamic implant for acute ankle syndesmosis rupture.

Objectives: To compare the clinical and radiographic outcome after stabilization of an acute syndesmosis rupture with either a static implant (a 3.5-mm metallic screw through 4 cortices) or a dynamic device (TightRope; Arthrex). Design: Multicenter randomized double-blind controlled trial. Settings: Study realized in 5 trauma centers (2 level 1 and 3 level 2) in 2 countries. Patients/Participants: Seventy subjects admitted for an acute ankle syndesmosis rupture entered the study and were randomized into 2 groups (dynamic fixation = 34 and static fixation = 36). The 2 groups were similar regarding demographic, social, and surgical data. Sixty-five patients (dynamic = 33 and static = 32) completed the study and were available for analysis. Intervention: Syndesmosis fixation in the static group was realized with a 4 cortices 3.5-mm cortical screw (Synthes) and in the dynamic group with 1 TightRope (Arthrex). Standardized rehabilitation process for the 2 groups: no weight bearing in a cast for 6 weeks and then rehabilitation without protection. Main Outcome Measurement: Olerud–Molander score. Results: Subjects with dynamic fixation achieved better clinical performances as described with the Olerud–Molander scores at 3 (68.8 vs. 60.2, P = 0.067), 6 (84.2 vs. 76.8, P = 0.082), and 12 months (93.3 vs. 87.6, P = 0.046). We also observed higher American Orthopaedic Foot and Ankle Society scores at 3 months (78.6 vs. 70.6, P = 0.016), but these were not significant at 6 (87.1 vs. 83.8, P = 0.26) or 12 months (93.1 vs. 89.9, P = 0.26). Implant failure was higher in the screw group (36.1% vs. 0%, P < 0.05). Loss of reduction was observed in 4 cases in the static screw group (11.1% vs. 0%, P = 0.06). Conclusions: Dynamic fixation of acute ankle syndesmosis rupture with a dynamic device seems to result in better clinical and radiographic outcomes. The implant offers adequate syndesmotic stabilization without failure or loss of reduction, and the reoperation rate is significantly lower than with conventional screw fixation. Level of Evidence: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Cost Analysis of In-Home Telerehabilitation for Post-Knee Arthroplasty

Background Rehabilitation provided through home visits is part of the continuum of care after discharge from hospital following total knee arthroplasty (TKA). As demands for rehabilitation at home are growing and becoming more difficult to meet, in-home telerehabilitation has been proposed as an alternate service delivery method. However, there is a need for robust data concerning both the effectiveness and the cost of dispensing in-home telerehabilitation. Objective The objective of this study was to document, analyze, and compare real costs of two service delivery methods: in-home telerehabilitation and conventional home visits. Methods The economic analysis was conducted as part of a multicenter randomized controlled trial (RCT) on telerehabilitation for TKA, and involved data from 197 patients, post-TKA. Twice a week for 8 weeks, participants received supervised physiotherapy via two delivery methods, depending on their study group allocation: in-home telerehabilitation (TELE) and home-visit rehabilitation (VISIT). Patients were recruited from eight hospitals in the province of Quebec, Canada. The TELE group intervention was delivered by videoconferencing over high-speed Internet. The VISIT group received the same intervention at home. Costs related to the delivery of the two services (TELE and VISIT) were calculated. Student’s t tests were used to compare costs per treatment between the two groups. To take distance into account, the two treatment groups were compared within distance strata using two-way analyses of variance (ANOVAs). Results The mean cost of a single session was Can

The Incidence of Thromboembolic Events in Surgically Treated Ankle Fracture

93.08 for the VISIT group (SD

Incidence and Characteristics of Atypical Femoral Fractures: Clinical and Geometrical Data

35.70) and

Gross Instability After Hip Arthroscopy: An Analysis of Case Reports Evaluating Surgical and Patient Factors

80.99 for the TELE group (SD

The impacts of pre-surgery wait for total knee replacement on pain, function and health-related quality of life six months after surgery.

26.60). When comparing both groups, real total cost analysis showed a cost differential in favor of the TELE group (TELE minus VISIT: -