Current concepts on the pathogenesis of osteonecrosis of the femoral head.

Treatment of atraumatic osteonecrosis of the femoral head is presently based not on disease prevention, but instead on the end-stage changes of bone associated with the necrotic lesion. Current diagnostic modalities are limited, by both cost and efficacy, in their ability to diagnose early-stage osteonecrosis. While many studies have assumed the cause of osteonecrosis is vascular occlusion, recent work suggests that alternate processes are primarily involved in the pathogenesis. By examining these concepts, a better understanding of osteonecrosis of the femoral head may lead to earlier diagnostic modalities and treatment protocols to prevent this devastating process from developing.