Wednesday, July 30, 2014

Avascular Necrosis

Definition

Avascular necrosis (of bone) is deterioration of bone due to a diminished blood supply.

Description

The reduced blood flow to the bone may be the result of blockage by a blood clot, medication, or the deliberate stoppage of flow during surgery or because of measures taken to control a hemorrhage (major bleed).

The most commonly affected sites are the proximal and distal femoral heads, the upper part of the leg bone that attaches into your hip. Other commonly affected sites include the ankle, shoulder and elbow.

Causes

Avascular necrosis of the bone is a complication of corticosteroid use, trauma, systemic lupus erythematosus, pancreatitis, alcoholism, gout, and sickle cell disease, as well as other diseases.

Symptoms

Patients may present with hip pain or (referred) knee pain. Physical examination will disclose that internal rotation of the hip - not movement of the knee - is painful.

Diagnosis

Initially, plain X-rays are often normal. An MRI (Magnetic Resonance Imaging), CT (Computed Tomography) scan, and bone scan are all more sensitive techniques.

Treatment

Most often, the section of bone that develops avascular necrosis needs to be replaced. If this develops in the proximal end of the femur, replacement of the head of the femur and the portion of the pelvis into which the hip inserts is necessary.

Questions

How is this condition treated?

What caused this condition?

Is this condition debilitating?

Will a wheelchair be needed in the advancing stages?

Does avascular necrosis spread to other bones?