Bilateral osteonecrosis of the femoral head in an adult man affected by congenital estrogen deficiency.

Osteonecrosis of femoral head is related to different predisposing factors. The pathogenesis is not completely understood, but an ischemic impairment seems to be one of the major determinants of bone necrosis. The association of bilateral necrosis of femoral heads and congenital aromatase deficiency is here reported. The absence of estrogen activity, as well as the persistence of unfused epiphyses for a long period of life, may be involved in the determinism of bilateral necrosis of bone femoral heads. The possibility of development of bone necrosis in patients affected by congenital estrogen deficiency needs to be considered and magnetic resonance imaging can be a useful method for an early detection of this disease.