Coxa vara, avascular necrosis and osteochondritis dissecans complicating solitary bone cysts of the proximal femur.

In 2 children with cysts in the upper end of the femur, there were 3 complications: coxa vara, avascular necrosis and osteochondritis dissecans. Coxa vara occurred in both cases and was due in 1 case to pathological fracture, and in the other case to growth disturbance. Avascular necrosis of the femoral head, a hitherto unreported complication of bone cyst of the upper end of the femur occurred in 1 patient following pathological fracture and resulted in osteochondritis dissecans of the femoral head.