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 patellofemeral joint (where the kneecap rubs against the lower portion of the thigh bone)
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)
Reviewed last on: 5/5/2008
Andrew L. Chen, MD, MS, Orthopedic Surgery and Sports Medicine, The Alpine Clinic, Littleton, NH. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
References
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.