Patellofemoral (puh-tel-o-FEM-uh-rul) pain syndrome is the most common cause of knee pain seen by doctors. It's common in people who participate in sports, especially females and young adults. Patellofemoral pain syndrome is sometimes called runner's knee.

The most common symptom is pain in the front of the knee, around the kneecap. The pain usually increases with running, stair climbing or squatting movements.

Simple treatments such as an ice pack and rest work best. Pain relievers available without a prescription and physical therapy exercises also can reduce pain. If simple measures don't relieve pain, surgery may be needed.