Avascular Necrosis
What is avascular necrosis?
Avascular necrosis (also referred to as aseptic necrosis or osteonecrosis, is a disease that results from poor blood supply to an area of bone causing bone death. This is a serious condition because the dead areas of bone do not function normally, are weakened, and can collapse. Pain associated with avascular necrosis is often severe and unrelenting.
What causes avascular necrosis?
Avascular necrosis can be caused by trauma and damage to the blood vessels that supply bone its oxygen. Other causes of poor blood circulation to the bone include an embolism of air or fat that blocks the blood flow through the blood vessels, abnormally thick blood (hypercoagulable state), and inflammation of the bloodvessel walls (vasculitis).
What conditions are associated with avascular necrosis?
Conditions that are associated with avascular necrosis include alcoholism, steroid usage, Cushing’s syndrome, radiation exposure, sickle cell disease, pancreatitis, Gaucher’s disease, and systemic lupus erythematosus.
How is avascular necrosis diagnosed?
The diagnosis of aseptic necrosis can be made with x-rays, but this is a later stage finding. Earlier signs of avascular necrosis can be detected with MRI scanning or suggested by nuclear bone scanning.
What is the treatment for avascular necrosis?
The treatment of aseptic necrosis is critically dependent on the stage of the condition. Early avascular necrosis (before x-ray changes are evident) can be treated with a surgical operation called a core decompression. This procedure involves removing a core of bone from the involved area and sometimes grafting new bone into the area. This allows new blood supply to form, preserving the bone. Weight bearing should be restricted.
Later stages of avascular necrosis (when x-ray changes have occurred) inevitably lead to seriously damaged bone and joints and requires joint replacement surgery.
