Hip Arthroplasty after Previous Arthrodesis

Total hip arthroplasty after previous arthrodesis has been associated with increased complications and decreased survivorship of the prosthesis. We evaluated pain, function, and the factors influencing survivorship of total hip arthroplasties after previous arthrodesis between 1985 and 2000 and compared these results with those obtained in prior years with the same procedure and in the same institution. We retrospectively reviewed 30 patients who had previous spontaneous or surgical arthrodesis. The minimum followup was 2 years (mean, 10.4 years; range 2–20.5 years). Seven failures were identified (23%). The overall survival free of failure was 86% at 5 years and 75% at 10 years. At last followup, 27 of the 30 patients (91%) had no or slight pain, 26 (87%) had a limp, and 18 (61%) needed a gait aid. Surgical arthrodesis, age younger than 50 years at the time of arthroplasty, and length of arthrodesis less than 30 years independently predicted failure. Conversion of arthrodesis to hip arthroplasty reliably decreases pain and improves function, but many patients will limp and require a gait aid. Our outcomes were similar to those after revision rather than after primary hip arthroplasty.