Aseptic necrosis is bone death caused by poor blood supply to the area. It is most common in the hip, knee, and shoulder.

Aseptic necrosis occurs when part of the bone does not get blood and dies. After a while part of the bone breaks off. If this condition is not treated, bone damage gets worse. Eventually, the healthy part of the bone may collapse.

Aseptic necrosis can be caused by disease, or a severe trauma, such as a break or dislocation, that affects the blood supply to the bone. Many times, no trauma or disease is present. This is called "idiopathic aseptic necrosis" -- aseptic necrosis without any known cause.

The following can cause aseptic necrosis:

• Long-term treatments with steroids
• Excessive alcohol use
• Sickle cell disease
• Radiation therapy
• Gaucher disease
• Decompression sickness

Some diseases that may be associated with the development of aseptic necrosis include:

• Gout
• Atherosclerosis
• Diabetes

Aseptic necrosis is most common in people between ages 30 and 60. Most aseptic necrosis cases in adults occur at the hip joint. The condition can also occur due to childhood cancer therapy.

Legg-Calvé-Perthes disease is a similar condition seen in children and adolescents.

There are no symptoms in the early stages of aseptic necrosis. As bone damage worsens, you may have the following symptoms:

• Pain in the joint that may increase over time, and will become very severe if the bone collapses
• Limited range of motion
• Groin pain if the hip joint is affected
• Limping if aseptic necrosis occurs in or below the hips

Your health care provider will do a complete physical exam to find out if you have any diseases or conditions that may affect your bones. You will be asked questions about your symptoms and medical history. The questions might include:

• When did the pain start?
• Does the pain spread (radiate) anywhere?
• Is the pain constant, or does it get better at night or at rest?
• Have you noticed any difference in how much or how far you can move (your mobility)?
• Do pain relievers help?
• Are you taking any steroids now, or have you ever taken them?
• Do you drink alcohol? If so, how much?

Be sure to let your health care provider know about any medications or vitamin supplements you are taking, even over-the-counter medicine.

After the exam, your doctor will order one or more of the following tests:

• X-ray
• MRI
• Bone scan
• CT scan

If your health care provider knows the reason for aseptic necrosis, part of the treatment will be aimed at the underlying condition. For example, if a blood clotting disorder is the reason, treatment will consist, in part, of clot-dissolving medicine.

If the condition is caught very early, you will take pain relievers and limit use of the affected area. This may include using crutches if your hip, knee, or ankle is affected. You may need to do range-of-motion exercises. Non-surgical treatment can often slow the progression of aseptic necrosis, but most people will need surgery.

Surgical options include:

• A bone graft
• A bone graft along with its blood supply (vascularized bone graft)
• Cutting the bone and changing its alignment to relieve stress on the bone or joint (osteotomy)
• Total joint replacement, in very advanced cases
• Removing part of the inside of the bone (core decompression) to relieve pressure and allow new blood vessels to form

You can find more information and support resources at the following organizations:

• National Osteonecrosis Foundation -- www.nonf.org
• ON/AVN Support Group Int’l Association --http://osteonecrosisavnsupport.org
• The Arthritis Foundation -- www.arthritis.org
• Center for Osteonecrosis Research and Education (CORE) -- http://www.osteonecrosis.org

Prognosis depends on the following:

• Stage of the disease when it was diagnosed
• Size of the area of bone involved
• Whether any other conditions were involved
• Age and general health of the person affected

The outcome can vary from complete healing to permanent damage in the affected bone.

Many cases of aseptic necrosis do not have a known cause, so prevention may not be possible. However, in some cases, you can reduce your risk by doing the following:

• Avoid drinking excessive amounts of alcohol.
• When possible, avoid high doses and long-term use of corticosteroids.
• Dive safely to avoid decompression sickness.

Canale ST (ed). Campbell's Operative Orthopaedics. 10th ed. Philadelphia, Pa: Mosby; 2003.

Lackner H, Benesch M, Moser A, Smolle-Juttner F, Linhart W, Raith J, Urban C.  Aseptic osteonecrosis in children and adolescents treated for hemato-oncologic diseases: a 13-year longitudinal observational study. J Pediatr Hematol Oncol. 2005 May;27(5):259-63.

Powars DR, Chan LS, Hiti A, Ramicone E, Johnson C. Outcome of Sickle Cell Anemia: A 4-Decade Observational Study of 1056 Patients. Medicine (Baltimore). 2005 Nov;84(6):363-376.