What is avascular necrosis?

In adolescents and young adults with avascular necrosis (AVN), the blood supply to the hip joint is interrupted, and the bone begins to die. Also called osteonecrosis, AVN can lead to tiny breaks in the bone and eventual collapse of the ball of the hip joint (femoral head). While the cause of AVN is unknown, we do know that it is often associated with several underlying conditions including sick cell disease, and other factors such as chemotherapy and steroid use.

What are symptoms of avascular necrosis?

Avascular necrosis (AVN) can cause pain in the hip, thigh or knee. The hip joint usually becomes stiffer, and pain can either start abruptly or build over weeks or months.

How is avascular necrosis diagnosed?

Avascular necrosis (AVN) is diagnosed in children after a detailed history has been collected, a physical exam has been completed, and X-rays have been taken. In cases of early AVN, however, X-rays may not show the condition, and further imaging like an MRI may be necessary.

Specialized MRI helps our doctors better understand what’s going on deep inside the hip socket. We may recommend using contrast by IV to help understand where there is and isn’t blood flow. This is sometimes called a perfusion MRI scan. 

How is avascular necrosis treated?

Non-surgical treatment options for avascular necrosis

When treating hip pain, non-surgical treatments should always be considered first. In some cases, conservative treatments such as rest, activity restriction, physical therapy, injections, and/or pain medication can resolve the pain and swelling.

When is surgery needed for avascular necrosis?

If the hip pain or discomfort caused by avascular necrosis (AVN) does not improve with non-operative treatment, or if your doctor is concerned about further collapse of the ball and worsening of your child’s condition, surgery for AVN may be recommended.

CHOP’s areas of expertise and care for avascular necrosis

The Hip Disorders Program within Children’s Hospital of Philadelphia’s (CHOP) Orthopedic Center, is one of the largest and most experienced pediatric hip programs in the nation, providing specialized care for infants, children, teens and young adults with hip conditions. Our coordinated team has expertise in diagnosing and treating a wide range of pediatric hip disorders, and our surgeons perform some of the most complex orthopedic surgical procedures in the world. 

For older teens or young adults with hip disorders, the Young Adult Hip Preservation Program is designed to meet the needs of patients who are active participants in their own healthcare.