Knee pain is a common complaint that affects people of all ages. Knee pain may be the result of an injury, such as a ruptured ligament or torn cartilage. Medical conditions — including arthritis, gout and infections — also can cause knee pain. Many types of minor knee pain respond well to self-care measures. Physical therapy and knee braces also can help relieve pain. In some cases, however, your knee may require surgical repair.

A knee injury can affect any of the ligaments, tendons or fluid-filled sacs (bursae) that surround your knee joint as well as the bones, cartilage and ligaments that form the joint itself . Patellofemoral pain syndrome is a general term that refers to pain arising between the kneecap and the underlying thighbone. It's common in athletes; in young adults, especially those whose kneecap doesn't track properly in its groove; and in older adults, who usually develop the condition as a result of arthritis of the kneecap.