Association between human immunodeficiency virus and osteonecrosis of the femoral head.

The records of a consecutive series of 50 patients treated operatively for osteonecrosis of the femoral head were reviewed to determine the prevalence of human immunodeficiency virus (HIV) as an isolated risk factor for osteonecrosis. Twelve patients had a history of trauma to the hip and were excluded from the study. The remaining 38 patients were treated operatively for nontraumatic osteonecrosis of the femoral head. Of these, 7 patients were HIV positive, and 31 were HIV negative. Of the 7 patients who were HIV positive, 4 (57%) had none of the known risk factors for osteonecrosis. Of the 31 patients who were HIV negative, 4 (13%) had none of the known risk factors for osteonecrosis. The difference between the groups was statistically significant, suggesting that HIV infection is a risk factor for the development of osteonecrosis of the femoral head.