Chondromalacia patella is the softening and degeneration of the tissue (cartilage) underneath the kneecap (patella).

Chondromalacia patella that occurs in adolescents and young adults is thought to be related to overuse, injury, or too much force on the knee. It is more common in females. Many young people have a slight problem with the position of the kneecap.

Chondromalacia patella may also be a sign of arthritis of the kneecap, which is usually seen in older individuals.

People who have previously had a dislocation, fracture, or other injury to the kneecap may be more likely to get chondromalacia.

• A grating or grinding sensation when the knee is extended
• Knee pain in the front of the knee that worsens after sitting for a long period of time
• Knee pain that worsens with using stairs or getting out of a chair
• Knee tenderness

The doctor will perform a physical examination. The knee may be tender and mildly swollen, and the kneecap may not be perfectly lined up with the femur (thigh bone).

When you straighten your knee, a grinding sensation may be felt below the kneecap. Pressing the kneecap when the knee is straight may be painful.

X-rays are usually normal, although a special x-ray view of the kneecap may show signs of arthritis or tilting.

Temporarily resting the knee and taking nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, naproxen, or aspirin may help relieve pain. Physical therapy, especially quadriceps strengthening and hamstring stretching, may be helpful.

Limit participation in sports or strenuous activity until the pain has gone away. Avoid activities that increase the knee pain, such as deep knee bends, until the pain improves.

If the alignment of the patella cannot be corrected with therapy, surgery may be an option. Depending on the type of misalignment, the surgery may be arthroscopic (using a camera, which allows a smaller incision) or open.

Chondromalacia patella usually improves with therapy and use of NSAIDs. For the few people who need it, surgery is successful most of the time.

The main complication is failure of treatment to relieve pain.

When surgery is necessary, surgical complications may include:

• Failure to relieve pain
• Infection
• Worsening pain

Call for an appointment with your health care provider if you have symptoms of this disorder.

Avoid trauma or abnormal stress on the knee. Keep the leg muscles strong and flexible, especially the quadriceps and the hamstrings.

May TJ. Persistent anterior knee pain. Am Fam Physician. 2007;76:277-278.