What is Avascular Necrosis?

Bone is living tissue that needs a constant supply of blood to survive. If blood supply to the bone is cut off, the bone dies, which is called avascular necrosis, or osteonecrosis. Eventually, it causes bones to break or collapse. Avascular necrosis most often occurs in the hip, but can also occur in other major joints, like shoulders, knees and ankles.

What Causes Avascular Necrosis?

Avascular necrosis is most common in people between ages 20 and 60. It’s not always clear what causes avascular necrosis. The most common causes include:

Fracture or dislocation

Breaking the femur (the large bone of your upper leg) or dislocating the hip joint can affect the blood supply to the bone.

Fatty deposits

Long-term use of steroids or alcohol can cause a build-up of fatty deposits in blood vessels. That can cause the vessels to narrow or become blocked, reducing blood flow to the bone.

Medical conditions

Diseases, such as Sickle cell disease and Gaucher disease, can reduce blood flow to the bones. Decompression sickness from deep sea diving can cause gas bubbles in the blood, reducing blood flow. 

Radiation therapy and chemotherapy

These cancer treatments can damage bone cells and the blood supply to bones.

What are the Symptoms of Avascular Necrosis?

Early on, there typically aren’t any symptoms of avascular necrosis. It can take several months for symptoms to develop. As the condition gets worse you may experience: 

• Pain in the joint that increases over time and becomes severe if the bone collapses
• Pain even when you’re not using or moving the joint 
• Limited range of motion
• Groin pain, if the hip joint is affected
• Limping, if the condition occurs in or below the hips
  
  

How is Avascular Necrosis Treated?

If the condition is diagnosed early, pain relievers and limiting your use of the affected area will help reduce your pain. Ultimately, you’ll likely need surgery. Our Orthopaedic team use our advanced training and diagnostic expertise to determine the best surgical option for you.

If surgery is necessary, our physicians can provide a referral to one of our affiliated orthopaedic surgeons. For more information on surgical options, please contact us at askortho@stelizabeth.com.