Resurfacing arthroplasty in osteonecrosis of the hip.

Approximately 10% of the total hip replacements performed in the United States are for osteonecrosis. Resurfacing arthroplasty has received renewed interest, with several new designs being implanted worldwide. Proponents of resurfacing arthroplasty describe the advantages of bone conservation, preservation of joint mechanics, more physiologic loading of the bone, lower incidence of perioperative complications, and easier conversion to a secondary procedure if failure occurs. Critics recite previous poor results including high failure rates with femoral and acetabular loosening, osteonecrosis of the femoral head, femoral neck fracture, and loss of acetabular bone stock making the secondary revision procedure more difficult. This article attempts to clarify the advantages and disadvantages of the resurfacing concept as it applies to the treatment of osteonecrosis of the femoral head.