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Kneecap dislocation - Overview

Alternative Names

Dislocation - kneecap; Patellar dislocation or instability

Definition of Kneecap dislocation:

Kneecap dislocation occurs when the triangle-shaped bone covering the knee (patella) moves or slides out of place. The problem usually occurs toward the outside of the leg.

Causes:

Kneecap (patella) dislocation is often seen in women. It usually occurs after a sudden change in direction when your leg is planted. This puts your kneecap under stress.

Dislocation may also occur as a direct result of injury. When the kneecap is dislocated, it can slip sideways and around to the outside of the knee.

Arthroscopy

Patellar dislocation

Knee arthroscopy - series

Reviewed last on: 6/13/2010
Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine; and C. Benjamin Ma, MD, Assistant Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

References

De Carlo M, Armstrong B. Rehabilitation of the knee following sports injury. Clin Sports Med. 2010;29:81-106.

Steiner T, Parker RD. Patella: subluxation and dislocation. 2. Patellofemoral instability: recurrent dislocation of the patella. In: DeLee JC, Drez D Jr., Miller MD, eds. DeLee and Drez's Orthopaedic Sports Medicine. 3rd ed. Philadelphia, Pa: Saunders Elsevier;2009:chap 22;sect C.

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