What is avascular necrosis?
Avascular necrosis, also called osteonecrosis is a condition in which bone death occurs because of inadequate blood supply to it. Lack of blood flow may occur when there is a fracture in the bone or a joint dislocation that may damage nearby blood vessels.
What are the causes of avascular necrosis?
Chronic use of high doses of steroid medications and heavy alcohol consumption are the two main risk factors of avascular necrosis. Initially, small breaks appear in the bone that may eventually collapse. The hip joint is most commonly affected; however, the knee and shoulder may also be involved.
Symptoms of avascular necrosis
The symptoms appear suddenly if it's a result of an injury. In other situations, the pain and stiffness may gradually appear over a period. Typically, avascular necrosis causes pain and restricted range of motion in the joint affected.
Diagnosis of avascular necrosis
Your doctor will diagnose the condition using imaging tests such as X-rays, MRI scan and bone scan that help rule out other causes of joint pain.
Treatment of avascular necrosis
The treatment for avascular necrosis aims at preventing further loss of bone and it depends on the bone damage that has occurred already. Conservative treatment would reverse early stages of avascular necrosis whereas surgical treatment may be required in more advanced stages.
Conservative approach
- Medications: Non-steroidal anti-inflammatory drugs (NSAID'S) may be prescribed that help control your pain and swelling.
- Rest: Restriction of physical activities and the use of crutches to decrease weight bearing on your joints may be beneficial.
- Exercises: Regular exercises that improve your range of motion may be done.
- Electrical stimulation: Electric currents promote new bone growth. They can be applied directly to the area of damage or through electrodes fixed on the skin. It helps to replace the damaged bone.
Surgical treatment
- Core decompression: During this procedure, a portion of the inner layer of the bone is removed to relieve the pressure inside the bone. This decreases the pain and allows the growth of new blood vessels thereby stimulates new bone growth.
- Bone transplant: A healthy bone from harvested from another part of your body is grafted into the affected area.
- Bone reshaping (osteotomy): This procedure is done in advanced stages and involves reshaping of the bone which is done to decrease the stress placed over the affected bone.
- Joint replacement: Joint replacement surgery is done as a last resort when the bone has collapsed needing artificial replacement.