Factors affecting impingement and dislocation after total hip arthroplasty - Computer simulation analysis.

Background: Studies on the causes and factors affecting dislocation after total hip arthroplasty have revealed conflicting results. The purpose of this study was to evaluate the factors affecting impingement and dislocation after total hip arthroplasty, using a 3-dimensional dynamic motion analysis.

Methods: The CT data of 53 patients (53 hips: anterior dislocation; 11 cases, and posterior dislocation; 42 cases) who experienced hip dislocation after total hip arthroplasty with posterior approach, and 120 control patients (120 hips) without dislocation were analyzed.

Serum interleukin 8 levels correlate with synovial fluid levels in patients with aseptic loosening of hip prosthesis.

Levels of inflammatory cytokines (tumor necrosis factor alpha, interleukin [IL] 6, and IL-8) in serum from patients with osteolysis on radiographs after hip arthroplasty [osteolysis(+), n = 28], patients without osteolysis after hip arthroplasty [osteolysis(-), n = 24], and nonoperated healthy subjects [controls, n = 20] were determined. In addition, cytokine levels in synovial fluid from patients undergoing revision total hip arthroplasty (n = 14) for loosening were measured and compared with each other and with the area of osteolysis on radiographs. Serum IL-6 and IL-8 levels were significantly higher in the osteolysis(+) group than in the osteolysis(-) or the control groups.

Rotational acetabular osteotomy for hip dysplasia: 61 hips followed for 8-15 years.

We operated on 54 patients (61 joints) with rotational acetabular osteotomy (RAO) due to dysplasia of the hip with pre- or early-stage osteoarthritis/arthrosis. The mean follow-up was 11 (8-15) years. The Merle d'Aubigné median score increased from 14 to 15.