Bone Chips in the Knee (Osteochondritis Dissecans)

What are bone chips in the knee?

Bone chips in the knee are small pieces of bone or cartilage that have come loose and float around in the knee joint. (Cartilage is tough, smooth tissue that lines and cushions the surface of the joints.)

The medical term for this condition is osteochondritis dissecans of the knee. Another term for this condition is chondral fracture. Sometimes the chips are called loose bodies.

What is the cause?

The chips usually result from an injury to the knee that caused a fragment of bone or cartilage to be chipped off the end of the thighbone or the back of the kneecap. The injury usually happens in the cartilage that covers the thighbone or kneecap (patella) It could happen after one serious injury to the knee or after repeated minor injuries. A problem with the blood supply to the bone may be part of the cause.

What are the symptoms?

Symptoms may include:

• Your knee may lock up from time to time.
• You may have bulges on the surface of your knee.
• Sometimes you may be able to feel the chips on the surface of your knee.
• Your knee is swollen and painful.
• You may not be able to fully bend or straighten your knee.

How is it diagnosed?

Your healthcare provider will ask about your symptoms, review your medical history, and examine your knee. Tests you may have include:

• X-ray
• magnetic resonance imaging (MRI), which uses a powerful magnetic field and radio waves to take pictures from different angles to show thin cross sections of the body

How is it treated?

You will need to rest your knee and avoid sports and activities that cause pain until the symptoms are gone. To lessen swelling and pain in the first day or two, your healthcare provider will probably tell you to:

• Put an ice pack, gel pack, or package of frozen vegetables, wrapped in a cloth, on the painful area every 3 to 4 hours for up to 20 minutes at a time.
• Take an anti-inflammatory medicine, such as ibuprofen, or other medicine as directed by your provider. Nonsteroidal anti-inflammatory medicines (NSAIDs), such as ibuprofen, may cause stomach bleeding and other problems. These risks increase with age. Read the label and take as directed. Unless recommended by your healthcare provider, do not take for more than 10 days.
• You may need to change your sport or activity to one that does not make your condition worse. For example, you may need to bicycle or swim instead of run. You may also need to rest if your knee is swollen and painful.

Sometimes surgery is needed to remove the fragments and repair the surface of the thighbone or kneecap. You may keep having problems until you have surgery to correct the problem.

How can I take care of myself?

• Rest your knee until the pain goes away.
• Follow your treatment plan.
• Keep all appointments for provider visits or tests.
• Tell your healthcare provider if you have new or worsening symptoms.

When can I return to my normal activities?

Everyone recovers from an injury at a different rate. Return to your activities depends on how soon your knee recovers, not by how many days or weeks it has been since your knee started bothering you. In general, the longer you have symptoms before you start treatment, the longer it will take to get better. The goal is for you to be able to get back to your normal activities as soon as is safely possible. If you do this too soon you may worsen your injury.

You may safely return to your normal activities when, starting from the top of the list and progressing to the end, each of the following is true:

• You can fully straighten and bend your knee without pain.
• Your knee is not swollen.
• Your injured knee and leg are as strong as the other knee and leg.
• You can walk and squat without pain.

How can I prevent bone chips in the knee?

Bone chips are usually caused by injuries to the knee that are not easily prevented.