Runner's knee is an overuse injury, where the kneecap or cartilage beneath it is being rubbed away because of a misalignment of the kneecap. The pain, usually a strong ache, is located beneath or around the edges of the kneecap. Pain is strongest after sitting for some time with your knees bent or when running or walking down hills or stairs. This is when the most stress is on your kneecap.
The cause is usually a combination of weak quadriceps and tight hamstrings or IT bands. However, overpronation can be a factor also. Rest and ice are the best cures for the symptoms. Strengthening the quadriceps and stretching the hamstrings and IT bands are the easiest (and least expensive) ways to cure runner's knee. However, if patellofemoral pain continues untreated, surgery is an option (sometimes the only one).
