A female on steroids developed hip pain. Investigations show the evidence of avascular necrosis of head of the femur. The most common fracture site in this patient will be:

Osteonecrosis of the femoral head can occur in young patients. Risk factors include steroid use, alcoholism, trauma, marrow-replacing diseases (such as Gaucher disease), high-dose radiation treatment, and hypercoagulable states (sickle cell disease, hypofibrinolysis, thrombophilia, protein S and C deficiencies). The disease course consists of decreased blood flow to the femoral head, resulting in osteonecrosis, subchondral fracture, and eventually collapse. Subchondral fracture of the hip is most clearly seen on the lateral radiograph. Also know: Avascular necrosis of the hip may be classified according the Ficat grading system: Type I (no radiographic signs of avascular necrosis) Type II (changes of the femoral head subchondral bone without collapse) Type III (subchondral fracture with collapse) Type IV (collapse of the femoral head with changes on the acetabular side) Ref: Srinivasan R.C., Tolhurst S., Vanderhave K.L. (2010). Chapter 40. Ohopedic Surgery. In G.M. Dohey (Ed), CURRENT Diagnosis & Treatment: Surgery, 13e.