Diagnosis of Osteonecrosis

If your doctor suspects you have osteonecrosis, he or she may take your medical history and do a physical exam. Your doctor may also order one or more imaging tests to see which bones are affected and to assess the degree of bone or joint damage. This information helps determine the stage of the disease. Early diagnosis increases the chance that treatment will be successful.

X-ray

X-rays are usually the first type of imaging study the doctor will order because they can also help rule out other causes of joint pain, such as a fracture or arthritis. However, an x-ray is not sensitive enough to detect bone changes in the early stages of osteonecrosis, so your doctor may order more tests if your x-ray is normal. If you are diagnosed with the disease, x-rays are often used to monitor the bones in the later stages.

Magnetic Resonance Imaging (MRI)

An MRI is a highly sensitive tool for visualizing bones and joints and can detect early signs of osteonecrosis before they are seen on an x-ray. An MRI may even pick up signs of osteonecrosis before you experience symptoms. MRIs can help provide your doctor with information on the degree of bone damage and the overall structure of the joint.

Computed Tomography (CT) Scan

A CT scan creates a clearer image than a plain x-ray does. Doctors can use a CT scan to assess the extent of bone damage, but they are less commonly used than MRIs because they are less sensitive.

Treatment of Osteonecrosis

The goal of treatment is to preserve joint function for as long as possible. If the disease is caught early, the bone is not weight bearing and the damaged area is small, the bone may heal on its own, and your doctor may recommend one or more nonsurgical treatment options. But in most cases, treatment involves surgery. At first, surgical procedures focus on preserving your natural joint; however, if the disease progresses and non-operative treatments do not work, some people may need a total joint replacement.

Your doctor will determine the best treatment for you based on:

• Your age.
• The stage of the disease.
• Which bone is affected and the amount of damage.

Nonsurgical Approaches

Nonsurgical approaches may help manage the symptoms of osteonecrosis, but generally they do not cure the disease or slow its progression. Your doctor may recommend one or more options, including:

• Anti-inflammatory medicines, to reduce pain and swelling.
• Physical therapy, to help reduce joint tenderness and stiffness, and to increase the joint’s range of motion.
• Use of a cane or crutches if the bone is weight bearing, to provide support and help relieve pain and weakness when walking.
• Corticosteroid injections to reduce pain and swelling. Because they are potent drugs, doctors typically prescribe the lowest dose possible to achieve the desired benefit.

Surgery

Most people with osteonecrosis eventually need surgery as the disease worsens.

There are three main types of surgery aimed at preserving the joint, but if these fail or if the diseased bone has already collapsed, you may need joint replacement surgery.

• Core decompression surgery. This is the most common surgery for osteonecrosis, and it usually helps treat the disease in the earlier stages. It involves drilling one or more narrow shafts through the bone, lowering the pressure within it  The procedure helps to relieve pain and slow disease progression. Core decompression is often combined with bone grafting to promote bone repair.
• Osteotomy. Doctors may recommend this procedure for cases that involve small areas of bone damage. In an osteotomy, surgeons reorient the position of the remaining bone so that healthy tissue supports the weight placed on the joint. This reduces stress on the damaged joint.  
• Bone graft. This surgical option treats advanced cases. The bone in a bone graft can come from your own body or from a donor, or it can be totally synthetic. In a procedure called a vascularized bone graft, a section of healthy bone from another part of your body is transplanted along with its blood supply, which helps to heal the area of osteonecrosis.
• Total joint replacement. If the bone in the joint has broken down too much, the joint will need to be replaced with an artificial one. Surgeons remove the damaged bone and cartilage and replace them with plastic, ceramic, and metal parts. Total joint replacements help relieve pain and increase the joint’s range of motion.

Who Treats Osteonecrosis?

Osteonecrosis is usually treated by:

• Orthopaedic surgeons, who specialize in treatment and surgery for bone and joint diseases.
• Mental health professionals, who provide counseling and treat mental health disorders such as depression and anxiety.
• Occupational therapists, who teach ways to protect joints, minimize pain, perform activities of daily living, and conserve energy.
• Physical therapists, who can help strengthen your muscles and improve joint function.
• Primary care doctors, such as family physicians or internal medicine specialists, who coordinate care between the different health care providers and treat other problems as they arise. Primary care doctors can provide nonsurgical treatment for osteonecrosis.
• Rheumatologists, who specialize in arthritis and other diseases of the bones, joints, and muscles and can provide nonsurgical care for osteonecrosis.