Runner's knee - or patellofemoral pain - is a condition caused by continual heavy stress on the knees, which is common in physically demanding activities such as running, jumping, skiing, cycling and playing soccer. It causes a dull, aching pain either under or around the front of the knee. The pain can be felt walking up or down stairs, kneeling, squatting or sitting for a long time with knees bent.
Runner's knee refers to a number of conditions which may cause pain under or around the front of the knee. These include:
Anterior knee pain syndrome: a result of irritation to the soft tissues, most often strained tendons, causing chronic pain in the front and center of the knee.
Patellofemoral malalignment: when