Osteonecrosis, also known as bone death, is the deterioration of bones and usually affects joints.

Osteonecrosis is a little-known condition in which bones are weakened due to the loss of blood flow. With limited blood flow, bones begin to break down and eventually die.

Though the disease is uncommon, approximately 10,000 to 20,000 cases are diagnosed each year in the United States. Most cases affect men and women from age 30 to 50 years old.

Jay R. Lieberman, MD, professor and chair of the USC Department of Orthopaedic Surgery at the Keck School of Medicine of USC and one of the world’s few experts in osteonecrosis, explained that osteonecrosis affects the area where bones connect to the joints, usually in the shoulder, hip, knee or ankle.

The first symptoms are pain in the joint under pressure or added weight. “As the disease progresses, you may experience pain while at rest,” said Dr. Lieberman.

Causes of osteonecrosis include:

  • Injury or trauma to the bone – If you have broken a bone or dislocated a joint, the break or dislocation can cut off the blood supply to the bone. This can limit your circulation and cause you to develop osteonecrosis.
  • Medications – Long-term and high doses of corticosteroid medications are linked to osteonecrosis. Medications that are used to treat inflammation such as prednisone are also linked to bone loss (osteoporosis).
  • Excessive alcohol use – Excessive alcohol consumption increases the number of fatty cells in your blood vessels, which blocks a consistent blood flow to the bones. This decreased blood supply over time can lead to osteonecrosis.
  • Other causes – Osteonecrosis is also linked to other conditions and treatments that affect blood flow, such as radiation and chemotherapy treatments; blood disorders such as sickle cell disease; and caisson disease, also known as the bends, a disease that is found in deep sea divers caused by surfacing too quickly.

How is osteonecrosis diagnosed?

Your doctor will conduct tests based on your age and the affected bone and joint. “The definitive diagnosis is usually made using an MRI, but changes also be seen on an X-ray,” Dr. Lieberman said.

Is osteonecrosis treatable?

There is no cure, so the main goal of treating osteonecrosis is to slow down the deterioration of the bone. Most non-surgical treatments are not a long-term solution.

Medications are used to alleviate pain. Mobility exercises will keep you mobile and improve your range of motion. But as your bone deteriorates or collapses, surgery eventually will be needed.

“There are several different surgical treatments that have been developed to prevent collapse of the femoral head,” Dr. Lieberman said. “Once the collapse occurs, the patient will usually require surgery to relieve the pain.”

Four types surgical procedures have been effective:

  • Core decompression, which removes the inner part of the bone to increase blood flow and reduce pressure
  • Osteotomy, which reshapes the affected bone to relieve stress on the joint
  • Bone grafts to replace diseased bone with healthy bone from another part of your body
  • Joint replacement to replace the joint with a mechanical one

The stage of the disease will dictate the best option for you.

If you have joint pain, consult the world-renowned experts at the USC Orthopaedic Surgery Center at Keck Medicine of USC.

If you are in the Los Angeles area and are looking for exceptional care from some of the top orthopaedic surgeons in the world, schedule an appointment by calling (800) USC-CARE (800-872-2273) or by visiting http://www.ortho.keckmedicine.org/request-an-appointment/.

By Heidi Tyline King