Bilateral hip osteonecrosis: influence of hip size on outcome

Abstract
OBJECTIVE To measure the volume of osteonecrosis in 30 patients with disease in both hips (one side with collapse and the other without at Ficat stage I). METHOD The volume of the osteonecrosis was measured by magnetic resonance imaging. RESULTS The progression to collapse was influenced by the size of the lesion in each patient. The first collapsed hip was that with the largest volume of osteonecrosis. CONCLUSION The volume of the osteonecrotic lesion on the second hip (stage I without collapse) is a good predictor of the time to collapse of this second hip.