Early failure of articular surface replacement XL total hip arthroplasty.

The ASR (articular surface replacement) XL (DePuy, Warsaw, Ind) metal-on-metal hip arthroplasty offers the advantage of stability and increased motion. However, an alarming number of early failures prompted the evaluation of patients treated with this system. A prospective study of patients who underwent arthroplasty with the ASR XL system was performed.

In vivo kinematics after a cruciate-substituting TKA.

Unlabelled: Patterns of motion in the native knee show substantial variability. Guided motion prosthetic designs offer stability but may limit natural variability. To assess these limits, we therefore determined the in vivo kinematic patterns for patients having a cruciate-substituting TKA of one design and determined the intersurgeon variability associated with a guided-motion prosthetic design.

Evaluation of off-loading braces for treatment of unicompartmental knee arthrosis.

Two analyses were performed to assess the effectiveness of off-loading knee braces in producing condylar separation of degenerative compartments in patients with unicompartmental knee osteoarthritis. All patients were analyzed using video fluoroscopy under weight-bearing conditions. In the initial study, a single brace was analyzed in 2 dimensions and demonstrated that medial condylar separation was obtained, with corresponding pain relief, in 78% of patients.

Cementless revision total hip arthroplasty without allograft in severe proximal femoral defects.

This study evaluates the difficult reconstructive challenge of severe proximal femoral bone loss. We present intermediate-term results of 46 hips with extensive proximal femoral bone loss that underwent revision total hip arthroplasty using cementless distal fixation without supplemental allograft. All were evaluated with the Harris hip score at a minimum of 2 years.

Bipolar reconstruction for recurrent instability of the hip.

Between 1986 and 1998, 81 total hip revisions were performed for recurrent instability. Twenty-three revisions were fixed cups to bipolars. Average follow-up was 50 months.

Underestimation of osteolysis in posterior stabilized total knee arthroplasty.

Periprosthetic osteolysis in total knee arthroplasty (TKA) has become a significant problem. Routine surveillance is warranted to detect problems that may not be symptomatic. The goal of these radiographs is to detect arthroplasty-related bone loss at an early stage to implement strategies to limit its extension.