Review Question - QID 101957

Avascular necrosis (AVN) arises from interruption to the blood supply of bone. Femoral head ischemia ultimately results in collapse of the necrotic subchondral segment. The femoral head is the most common location for AVN.

Atraumatic AVN is associated with
- Drugs – corticosteroids and alcohol
- Thrombotic occlusion from hemoglobinopathies such as sickle cell disease. Sickle cells are noted on the peripheral blood smear.
- Vasculitis such as systemic lupus erythematosus

AVN of the femoral head presents with groin and buttock pain aggravated by weight bearing. Physical examination reveals painful restriction in range of motion, with greatest limitation in abduction. There is no localized swelling, erythema or temperature change. MRI is used to diagnose AVN of the femoral head.

Half of sickle cell disease patients experience vaso-occlusive crisis. Vaso-occlusive crisis presents as severe pain in the abdomen, bones, joints and soft tissues. It may present as a dactylitis (painful swelling of the hands and feet) in children.

Choice A – Osteoarthritis occurs in older patients. Osteoarthritic hip pain is aggravated by activity and relieved by rest.
Choice B – Septic arthritis manifests with acute onset of pain in the hip. Examination will reveal local warmth and swelling.
Choice D – Trochanteric bursitis presents with pain over the hip on walking. There may be discomfort lying on the affected side. Examination demonstrates local tenderness and swelling over the greater trochanter.
Choice E – Rheumatoid arthritis presents and pain and deformity in the small joints of the hands and wrist. It is characterized by morning stiffness in the affected joints.