Avascular necrosis, also known as osteonecrosis, is the death of bone tissue due to a lack of blood supply. Bone necrosis occurs when there are tiny breaks in the bone that eventually lead to the bone's collapse.

What causes avascular necrosis of the hip bone?

Avascular necrosis occurs when blood flow to a bone is interrupted. Loss of blood flow can result from joint injury, narrowed or clogged blood vessels (from fat or sickle cell anemia), or from excessive pressure inside the bone (caused by conditions like Legg-Calve-Perthes disease or Gaucher's disease).

What does avascular necrosis of the hip bone feel like?

Avascular necrosis is characterized by persistent pain and stiffness in the affected joint, as well as a reduced range of motion.

When the hip bone becomes necrotic, pain radiates from the hip and into the groin, down the thigh, and into the knee.

In some cases, symptoms slowly develop over a period of several months. However, symptoms may appear suddenly after an injury. Some patients experience no symptoms at all.

How do I know if I have avascular necrosis of the hip bone?

Your doctor may order imaging tests like x-rays, magnetic resonance imaging (MRI), or a bone scan to examine the necrotic bone and determine diagnosis.

How is avascular necrosis of the hip bone treated?

The treatment you receive depends on the amount of bone loss you have already endured, and treatments focus on preventing further bone loss. Treatments can consist of a combination of medication, therapy, and surgical procedures.

• Medication: Anti-inflammatory drugs, such as aspirin or ibuprofen are commonly prescribed to relieve the pain and inflammation commonly associated with avascular necrosis. Additionally, biophosphates, or osteoporosis medicines, are often prescribed to slow the progression of the condition.
• Physical therapy: Physical therapy exercises may help improve range of motion in the affected joint. Meanwhile, restriction of certain physical activities will reduce the weight and pressure on the bone, reducing symptoms.
• Surgery: Typically, progressive cases of avascular necrosis require surgery.
  
  The most common procedures are:
  
  Core decompression: In this procedure, a portion of the inner layer of the bone is removed. This helps to reduce pain symptoms by relieving pressure within the bone. Due to the new space, the bone has room to form new blood vessels, which encourage the production of new bone.
  
  Bone grafting: In a bone graft, healthy bone is transplanted from another part of the body into the area affected by avascular necrosis. This procedure is often done in conjunction with core decompression.
  
  Osteotomy: This bone-reshaping procedure reduces the amount of stress placed on the area affected by avascular necrosis. Recovery can take up to a year.
  
  Total hip replacement surgery: This procedure is considered if other treatments are not working, or if your diseased bone has already collapsed. Total hip replacement surgery replaces your joint with an artificial one. Recovery can take months, and requires the patient to learn how to use the new joint.

If a surgical procedure is necessary, you and your doctor will work together to determine what method is best for you.

Duke Orthopaedics treats hip bone necrosis at locations throughout North Carolina, including Raleigh, Durham, Cary, and Chapel Hill, North Carolina.

Hip Bone Necrosis Treatment Videos

Watch an educational video about treatment of avascular necrosis of the hip bone.