Osteonecrosis (Avascular Necrosis of Bone)

A complication of

• Corticosteroid use

• Trauma

• Systemic lupus erythematosus (SLE)

• Pancreatitis

• Alcoholism

• Gout

• Sickle cell disease

• Dysbaric syndromes

• Knee menisectomy

• Infiltrative diseases (eg, Gaucher disease)

The natural history is usually progression of the bony infarction to cortical collapse, resulting in significant joint dysfunction

Most commonly affected sites are the proximal and distal femoral heads, leading to hip or knee pain

Other commonly affected sites include the ankle, shoulder, and elbow

Osteonecrosis of the jaw is associated with use of bisphosphonate therapy, usually when the bisphosphonate is used to treat metastatic cancer or plasma cell myeloma rather than osteoporosis

Hip or knee pain

• Many patients with hip disease first present with pain referred to the knee; however, internal rotation of the hip—not movement of the knee—is painful

Initially, radiographs are often normal

MRI, CT scan, and bone scan are more sensitive techniques

Differential diagnosis

• Osteoarthritis or rheumatoid arthritis

• Fracture

• Joint pain resulting from other cause

Avoidance of weight bearing on the affected joint for at least several weeks

Surgical core decompression is controversial

Total hip replacement is the usual outcome for all patients who are suitable candidates