Revision hip arthroplasty for late instability secondary to polyethylene wear.

We evaluated the outcome of revision arthroplasty for polyethylene wear presenting as late dislocation. The computerized databases at two institutions were reviewed to identify all patients presenting with first time dislocation five or more years after total hip arthroplasty. Records and radiographs were then evaluated, and patients whose late dislocation occurred in the presence of greater than two millimeters of polyethylene liner wear with no other etiology for dislocation were identified. There were 22 patients with a mean age of 57.8 years at primary procedure. The average time from initial arthroplasty to dislocation was 9.0 years. Revision surgery to address polyethylene wear and instability was performed at a mean of 11.1 years (range 5.8 to 23 years). Revision surgery restored stability to eighteen patients (eighty-two percent). Polyethylene wear can and is associated with late dislocation after hip arthroplasty. Exchange of polyethylene lining of a metal backed implant or revision of the all polyethylene acetabular component can successfully address late instability in the majority of patients.