Anterior knee pain is pain that occurs at the front of the knee.

The health care provider will perform a physical examination of the knee to confirm and assess the pain.

Tests that may be performed to rule out possible structural damage to the knee or connective tissue include the following:

• Joint CT scan
• Joint x-ray
• MRI scan of the knee

Common causes of runner's knee include rotation (pronation) and lateral (away from the middle) pulling of the kneecap. This causes the kneecap to become misaligned with the connective tissues and muscles involved with knee movement.

Anterior knee pain may also be caused by:

• Arthritis
• Cartilage injury
• Pinching of the inner lining of the knee with knee motion (synovial impingement, or plica syndrome)
• Poor alignment of the patellofemoral joint (where the kneecap rubs against the lower portion of the thigh bone)
• Softening of the cartilage under the kneecap (chondromalacia patellae)
• Tendinitis of the quadriceps tendon (where the thigh muscles attach to the top of the kneecap) or patellar tendon (where the kneecap attaches to the shin bone)

Symptoms include knee pain below the kneecap and on the sides of the kneecap, particularly with deep knee bends or prolonged sitting.

In cases of runner's knee, pain occurs first when running downhill then gets worse and occurs with all running. Finally, pain is present even when you do not run.

Treatment of anterior knee pain involves resting the knee and not running until you can do it without pain.

A sports medicine specialist or physical therapist may prescribe stretching exercises for the hamstrings and quadriceps, and strengthening exercises for the muscle that pulls the kneecap toward the center of the body. You can substitute bicycling for other exercise if you can do it without pain.

Special shoe inserts and orthotics (support devices) may help prevent further injury after healing.

Do NOT perform deep knee bends or overuse the knee until your symptoms improve.

Call your health care provider if knee pain persists in spite of resting the joint.

To help prevent sports injuries:

• Warm up properly before exercise.
• Stretch after warm-up or exercise.
• Cool down after exercise.

Dixit S, DiFiori JP, Burton M, Mines B. Management of patellofemoral pain syndrome. Am Fam Physician. 2007;75:194-202.

May TJ. Persistent anterior knee pain. Am Fam Physician. 2007;76:277-278.