Osteochondritis Dissecans (Bone Chips) of the Knee

What is osteochondritis dissecans of the knee?

Osteochondritis dissecans of the knee is a disorder in which there is an injury to the bone or cartilage which make up the knee joint. The cartilage covering the femur (thighbone) or kneecap (patella) are usually affected. There can be fragments of bone or cartilage which come loose and float around in the knee joint. Other terms for this condition are chondral fracture and osteochondral fracture. The fragments may also be referred to as a joint mouse or loose bodies.

How does it occur?

There has usually been a previous injury to the knee that caused a fragment of bone or cartilage to be chipped off the end of the femur or the back of the patella.. This may be due to a significant injury or due to repeated minor injuries. A problem with the blood supply to the bone may be part of the cause.

What are the symptoms?

Your knee may lock up from time to time. You may see bulges along the joint surface. You may be able to feel these chips or loose bodies along the surface of your knee joint at various times. Your knee can become swollen and painful. You may not be able to fully bend or straighten your knee.

How is it diagnosed?

Your healthcare provider will examine your knee and may find that it clicks or locks. Fragments may be felt along the joint line. An X-ray or a magnetic resonance imaging (MRI) may show bony fragments or the defects in the femur or patella.

How is it treated?

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.

How long will the effects last?

The symptoms from osteochondritis dissecans may continue until surgery is done to correct the problem. Ask your healthcare provider when you will be able to return to your normal activities. If you feel that your knee is giving way or if you develop pain or have swelling in your knee, you should see your healthcare provider.

When can I return to my normal activities?

Everyone recovers from an injury at a different rate. Return to your activities will be determined by how soon your knee recovers, not by how many days or weeks it has been since your injury has occurred. In general, the longer you have symptoms before you start treatment, the longer it will take to get better. The goal of rehabilitation is to return you to your normal activities as soon as is safely possible. If you return 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:

• Your injured knee can be fully straightened and bent without pain.
• Your knee and leg have regained normal strength compared to the uninjured knee and leg.
• Your knee is not swollen.
• You are able to walk, bend, and squat without pain.

How can I prevent osteochondritis dissecans of the knee?

Osteochondritis dissecans is usually caused by trauma to the knee and is not preventable.