Revision surgery after triple-cup arthroplasty.

Although various operative procedures have been applied for advanced or terminal osteoarthritis of the hip joints in relatively young patients, the long-term results are controversial. Since 1974, we have performed the triple-cup arthroplasty developed by Aoki in 110 patients who were comparatively young. The triple-cup assembly is composed of stainless-steel outer and inner cups between which a high density polyethylene cup is incorporated, so that there are basically four mobile surfaces, but the major movement is actually taking place between the outer cup and the plastic cup [8]. We have sometimes encountered migration of the cups, which caused hip joint pain and decreased the range of motion. Revision surgery was required for 25 hip joints in 21 patients (23%). The acetabulum was very thin in almost all cases, so that reaming of the cavity had to be restricted to the minimum possible. The femoral head in the cup was often covered with a layer of fibrous tissue. We could utilize the femoral head as a bone graft, even though the residual volume of bone varied in each case. The result of revision surgeries after the triple-cup arthroplasty was good clinically and radiographically at last follow-up.