Overview Of Osteonecrosis
Osteonecrosis is bone death caused by the poor blood supply. It is most common in the hip and shoulder but can affect other large joints such as the knee, elbow, wrist, and ankle.
Commonly Associated With
Avascular necrosis; Bone infarction; AVN; Aseptic necrosis
Causes Of Osteonecrosis
Osteonecrosis occurs when part of the bone does not get blood and dies. After a while, the bone can collapse. If osteonecrosis is not treated, the joint deteriorates, leading to severe arthritis.
Osteonecrosis can be caused by disease or by severe trauma, such as a fracture or dislocation, that affects the blood supply to the bone. Osteonecrosis can also occur without trauma or disease. This is called idiopathic — meaning it occurs without any known cause.
The following are possible causes:
- Using oral or intravenous steroids
- Excessive alcohol use
- Sickle cell disease
- Dislocation or fractures around a joint
- Clotting disorders
- HIV or taking HIV drugs
- Radiation therapy or chemotherapy
- Gaucher disease (a disease in which harmful substance build-up in certain organs and the bone)
- Systemic lupus erythematosus (an autoimmune disease in which the body’s immune system mistakenly attacks healthy tissue such as the bone)
- Legg-Calve-Perthes disease (childhood disease in which the thigh bone in the hip doesn’t get enough blood, causing the bone to die)
- Decompression sickness from a lot of deep-sea diving
- When osteonecrosis occurs in the shoulder joint, it is usually due to long-term treatment with steroids, a history of trauma to the shoulder, or the person has sickle cell disease.
Symptoms Of Osteonecrosis
There are no symptoms in the early stages. As bone damage worsens, you may have the following symptoms:
- Pain in the joint may increase over time and becomes severe if the bone collapses
- Pain that occurs even at rest
- Limited range of motion
- Groin pain, if the hip joint is affected
- Limping, if the condition occurs in the leg
- Difficulty with overhead movement, if the shoulder joint is affected
Exams & Tests
Your health care provider will do a physical exam to find out if you have any diseases or conditions that may affect your bones. You will be asked about your symptoms and medical history.
Be sure to let your provider know about any medicines or vitamin supplements you are taking, even over-the-counter medicine.
After the exam, your provider will order one or more of the following tests:
- X-ray
- MRI
- Bone scan
- CT scan
Treatment Of Osteonecrosis
If your provider knows the cause of osteonecrosis, part of the treatment will be aimed at the underlying condition. For example, if a blood clotting disorder is a cause, treatment will consist, in part, of clot-dissolving medicine.
If the condition is caught early, you will take pain relievers and limit the 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. Nonsurgical treatment can often slow the progression of osteonecrosis, but most people will need surgery.
Surgical options include:
- A bone graft
- A bone graft along with its blood supply (vascularized bone graft)
- Removing part of the inside of the bone (core decompression) to relieve pressure and allow new blood vessels to form
- Cutting the bone and changing its alignment to relieve stress on the bone or joint (osteotomy)
- Total joint replacement
