Partial resurfacing arthroplasty of the femoral head in avascular necrosis- Methods, indications, and results

The current study reports results using a partial surface replacement for o steonecrosis of the femoral head. The surgical technique, implant design, a nd instrumentation cause minor soft tissue disruption and require little bo ny resection. Thirty-seven prostheses were placed in 33 patients during the past 7 years. The mean age of the patients was 43 years (range, 24-59 year s), and the preoperative Ficat classification was Stage III in 26 hips, Sta ge IV in 10, and Stage II in one hip. For the surviving prostheses, the mea n followup was 49 months (range, 24-89 months). Of the 28 surviving implant s, 24 continue to function well and the patients have excellent or good hip scores according to the Merle d'Aubigne system. There were nine failures, mainly attributable to the extension of the osteonecrosis. In comparison wi th alternative techniques, the operative surgery for partial surface replac ement is straightforward, requiring little preoperative planning and immedi ate weightbearing postoperatively. Should failure occur, little bone stock loss is incurred and revision to a total hip replacement is as simple as pr imary hip arthroplasty.