Secondary avascular necrosis in coxarthrosis: a morphologic study.

Secondary subarticular avascular necrosis was observed grossly in 11.7% of femoral heads removed surgically because of osteoarthritis (OA). In most cases the necrosis was superficial, however in 15% of the 82 cases of secondary necrosis the necrosis was deep and wedge shaped similar in appearance to the lesions seen in primary subarticular avascular necrosis. Most of the lesions were seen in the early stage of OA and it is suggested that the lesion may interfere with the subsequent reparative phenomenon.