The patella is the bone that makes the knee cap. Patellofemoral pain syndrome is a condition in which pain is felt under the kneecap. This pain occurs during exercise or movement. It is most common during weight bearing activities such as running. It is often increased by going down stairs or down hills.
It is caused by abnormal movement of the patella. As the leg extends and flexes, the patella normally moves both up and down, and tilts slightly. It should not touch the other bones of the knee.
The femur is the thigh bone. This bone forms the upper part of the knee. In people with patellofemoral pain syndrome, the patella painfully rubs against the femur. If you have knee or joint pain during activity, call your doctor.
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There is no single cause for this condition. It can be due to a number of different factors or conditions. These conditions include:
The following factors increase your chance of developing patellofemoral pain syndrome:
The first symptom is pain around or under the kneecap. The pain may first occur during high-impact activities. This includes playing sports or going down stairs. As the condition gets worse, the pain may be triggered by long periods of sitting. This is sometimes called movie-goer’s sign. It is thought to be caused by the pressure on the kneecap while the leg is flexed. Other symptoms include:
These symptoms may be caused by other, less serious health conditions. If you experience any one of them, see your physician.
Your doctor will first ask about your symptoms. A medical history will also be taken. To rule out other disorders, your doctor may want you to have the following tests:
Your doctor may refer you to a specialist. Orthopedic surgeons focus on bone and joint disorders.
The initial step is to rest the knee. High-impact activities should be switched for lower impact exercise. For example switch running for swimming. Your doctor may suggest that you apply ice to the kneecap after activity.
Longer term treatment involves a number of different strategies, including:
Most people will benefit from strengthening the muscles around the knee. This includes the quadriceps muscles in the thigh as well as other muscles near the hip. Physical therapists can recommend specific exercises. This treatment is very helpful. It can take 6 to 12 weeks to see an improvement.
Some people may benefit from nonsteroidal anti-inflammatory agents (NSAIDs). These may include
and Advil. They may be helpful in relieving the pain. They work best when combined with other treatments, such as physical therapy.
Many people find relief from knee braces or knee sleeves. These devices typically have a cut-out in the knee cap area. They are designed to hold the kneecap in place during activity. Some are designed to hold the patella from going too far laterally.
Certain methods of taping the patella in position have also been helpful to many patients.
Special shoe inserts, called orthotics, may also be helpful. They are most helpful when the condition is due to dysfunction in the foot (as in flat feet or excessive pronation).
In rare cases, people who do not respond to other forms of treatment may be recommended for surgery. This will be done to correct malalignment of the patella.
It may not be possible to totally prevent the development of this condition. There are steps you can take to reduce your risk and avoid making the it worse. These measures include:
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