Patellofemoral pain syndrome (runner's knee) is a condition in which pain is felt under the kneecap of the knee joint. This pain occurs during exercise or movement, particularly during weight bearing activities such as running. It is often increased by going down stairs or down hills.
The pain is caused by abnormal movement of the patella, the kneecap. As the leg extends and flexes, the patella normally moves both up and down, and tilts slightly without touching the other bones of the knee.
In people with patellofemoral pain syndrome, the patella painfully rubs against the thighbone (femur) which forms the upper part of the knee joint. If you experience knee or joint pain during activity, call your doctor to determine what therapy is appropriate.




