Avascular necrosis, also called osteonecrosis is a condition in which bone death occurs because of inadequate blood supply to it. In the hip, this occurs in the femoral head. Lack of blood flow may occur as a results of numerous causes, such as hip trauma, chronic use of high doses of steroid medications, and heavy alcohol consumption. Sometimes, the definite cause is not known. Initially, small areas of bone loss develop that may progress to eventual collapse of the femoral head.
Typically, avascular necrosis causes pain and restricted range of motion in the joint affected. Diagnosis is made on the basis of history, physical exam, and imaging tests such as X-rays and MRI scan.
The treatment for avascular necrosis aims at preventing further loss of bone and it depends on the stage of the disease. Conservative treatment is indicated in early stages of the disease whereas surgical treatment may be required in more advanced stages.
- Medications: Non-steroidal anti-inflammatory drugs (NSAIDs) may be prescribed to help control pain and swelling. There is also emerging role for bisphosphonates in early stages.
- Rest: Restriction of physical activities and use of crutches to decrease weight bearing on your affected hip may be beneficial during acute flares of pain.
- Exercises: Regular exercises that improve the hip motion may be beneficial.
- Core decompression: During this procedure, the inside of the femoral head is drilled to decrease the pressure inside the bone and stimulate new bone growth.
- Bone transplant: A healthy bone harvested from another part of the body is grafted into the affected area.
- Bone reshaping (osteotomy): This procedure involves reshaping of the femoral head to decrease the stress placed over the affected part of it.
- Joint replacement: Joint replacement surgery is done as a last resort when arthritis has developed.