Enoxaparin prevents steroid-related avascular necrosis of the femoral head.

Nontraumatic osteonecrosis of the femoral head is still a challenging problem in orthopedic surgery. It is responsible for 10% of the 500,000 hip replacement surgeries in the USA and affects relatively young, active patients in particular. Main reasons for nontraumatic osteonecrosis are glucocorticoid use, alcoholism, thrombophilia, and hypofibrinolysis (Glueck et al.