Core decompression in atraumatic osteonecrosis of the hip.

Core decompression for osteonecrosis of the femoral head continues to be a controversial procedure. We report the results of core decompression in the treatment of hip osteonecrosis. Forty-two patients (67 hips) were evaluated. Minimum follow-up was 2 years. Preoperative outcome instruments were assessed. Volume of involvement (%) from magnetic resonance imaging was assessed. Failure was described as a total hip arthroplasty (THA). Mean patient age was 40.26 years. The average clinical and radiologic follow-up was 40.7 months and 33.1 months. The average Harris Hip Scores preoperatively and postoperatively were 49 and 58. None of the hips classified as Ficat I progressed to THA, whereas 17% of Ficat II hips and 66% of Ficat III hips progressed to THA. Our results demonstrate no relationship between the volume of involvement of the femoral head or the location of the lesion in progression to collapse. Staging with the Ficat classification demonstrated the most statistically significant correlation with progression to THA. The SF-36 scores at last follow-up on our patients were significantly worse than patients undergoing THA.