January 6, 2012
Dear Mayo Clinic:
Is pain directly under my kneecap anything to be concerned about?
Knee pain is fairly common and can affect people of all ages. Your pain could be the result of an injury or could be a more serious medical condition.
Pain directly under the kneecap can be attributed to one of several conditions. Among the most common is chondromalacia, more commonly known as "runner's knee." This condition usually happens to people who participate in high-impact exercise, such as running, or sports that require a lot of stopping and starting.
Chondromalacia is a softening or thinning of the cartilage under the kneecap. Its early form is more likely to occur in young athletes who are otherwise healthy. Sometimes, the condition can result from a direct blow or trauma to the kneecap. Often, people with chondromalacia may feel a crunching sensation when placing their hand over the kneecap and bending the knee or when climbing down stairs. Sitting for long periods with the knee bent may cause discomfort.
A similar crunching sensation may be felt with osteoarthritis of the knee, which typically affects patients over age 50. Osteoarthritis often affects the entire knee rather than simply the kneecap area. With osteoarthritis, the cartilage, which serves as a "shock absorber," is progressively worn away, exposing bare bone and causing pain. In some people, osteoarthritis is hereditary; for others, the cause could be previous trauma to the knee.
Another common condition that causes knee pain is patellar tendinitis, an injury that affects the tendon connecting the kneecap (patella) to the shinbone. Also known as "jumper's knee," it is most common in athletes who jump frequently — such as basketball, soccer and volleyball players. The soreness in this condition is typically felt just below the kneecap, which may be tender to the touch.
If you notice that your knee seems to slide out of place, you may have some 'maltracking' or patellar instability. Maltracking occurs when the knee doesn't track normally in its groove and moves to one side instead. In patellar instability, the kneecap actually pops out of joint. This usually occurs with planting and twisting maneuvers, and can be quite painful.
If you have difficulty walking, instability, frequent persistent swelling, or pain that wakes you from sleep, see your family doctor. You may be referred to a doctor specializing in rehabilitation (physiatrist or sports medicine specialist) or joint surgery (orthopedic surgeon).
Although knee surgery seems to be popular these days, the mainstay of treatment for most knee pain is nonsurgical. For patients with chondromalacia or patellar tendinitis, surgery is not typically recommended. Instead, patients are usually told to temporarily cease high-impact sports while beginning a physical therapy program.
Physical therapy exercises will help strengthen the muscles around your hip and core as well as around the knee to make it more stable. Exercises are likely to focus on the hip abductors, hip extensors, quadriceps and hamstrings, as well as exercises to improve your balance. Ice and compression should be used to control any swelling. Orthotics and bracing are sometimes helpful, particularly if instability is an issue. Your doctor may also recommend cortisone or hyaluronic acid injections. Once the pain resolves, it is important to resume your previous activities gradually to prevent recurrence of the pain.
There are some things you can do to help prevent knee pain from occurring in the first place, or having it become a serious condition. Maintaining a healthy weight, strengthening your hip and core muscles, and listening to your body are important. Many people tend to ignore pain until it becomes unbearable. Listen to your body and take it easy when pain flares up.
— Diane Dahm, M.D., Orthopedic Surgery, Mayo Clinic, Rochester, Minn.