Method

A randomized clinical trial was undertaken to assess the effect of large femoral heads on dislocation after revision total hip. Patients undergoing revision hip arthroplasty at seven centers were randomized to 32mm head or 36/40mm head. Patients were stratified according to surgeon. Primary endpoint was dislocation. Rates were compared with Fishers exact test. Secondary outcome measures were quality of life: WOMAC, SF-36 and satisfaction. One hundred eighty four patients were randomized: 92 in the 32mm head group and 92 in the large head group. Baseline demographics were similar in the two groups. Patients were followed from two to five years postoperatively

Method

The study group included 25 consecutive patients who had two stage revision TKA to treat infection with an average follow up of 3.25 1.5 years (range 2–6). In all patients the diagnosis of infection was made using standard serum parameters as well as aspiration for joint fluid analysis. Eight patients had posterior stabilized TKAs and 17 patients with had constrained condylar TKAs. Clinical evaluation included the Knee Society Knee Scores (KSKS) at each follow-up visit as well as a detailed record of any difficulties or complications.

Method

Twenty-seven knees in patients with a mean age of 65 years (range, 40 to 80 years) were treated with two-stage revision of an infected total knee arthroplasty using a metal-on-polyethylene dynamic prosthetic spacer fixed with antibiotic-impregnated cement. Clinical outcomes were evaluated using maximum active knee range of motion, as well as modified Knee Society knee scores and incidence of re-infection at a minimum one-year follow-up. The results were compared to those achieved at similar follow-up in 10 patients treated with a static cement spacer. Demographic profile as measured by age and gender, and pre-operative Knee Society scores and range of motion were similar between the two groups.

Method

The study group comprised eighteen patients who had undergone conversion of unilateral hip fusion to total hip replacement between 1996 and 2007. There were five men and 13 women. The diagnosis prior to fusion was traumatic injury in eight patients, developmental dysplasia in three patients, and septic arthritis in seven patients. Four of the patient who had septic arthritis in childhood had spontaneous hips fusion while the other underwent surgical arthrodesis.

The mean age at the time of conversion was 53 years (range, 21–77) and the mean time between fusion and conversion to hip replacement was 33 years (range, 11–60). Mean follow up was five years (range 2–15 years).

Data was collected by retrospective review of a prospective database. Uncemented acetabular components were used in all cases and uncemented femoral components were used in all but two patients. In three patients with abductor and soft tissue deficiency an intraoperative decision was made to use a constrained acetabular liner.

Method

The angle at the intersection of lines from the middle of the tibial tuberosity and from its medial border to the tibial geometric center was measured in 50 patients with normal tibia. The geometric center was determined on an axial CT slice at 10mm below the lateral tibial plateau and transposed to a slice at the level of the most prominent part of the tibial tuberosity.

Similar measurements were performed in 25 patients after TKA in order to simulate the intra operative appearance of the tibia after making its proximal resection.

Method

A prospective randomized control trial was designed and conducted to compare the MIS Anterolateral Approach to that of the MIS Posterolateral and MIS Direct Lateral Approach. Contemporary methods for economic evaluation were used to ascertain direct and indirect costs (in Canadian dollars) along with clinical effectiveness outcomes (SF6D and Pat5D utility measures). University and hospital ethics was obtained and patients were recruited and consented to participate in the RCT resulting in the assignment of 130 patients MIS hip arthroplasty procedures. Baseline patient demographics, comorbidity, quality of life, and utility were obtained for all patients. In-hospital costing data was obtained including operating room and patient room costs as well as medication, rehab and complications. Post-discharge costs were calculated from direct and indirect costs of medication, rehab, medical costs and complications until one year post-operatively. Clinical effectiveness measures were administered at intervals until one year post-operatively.