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Knee cap dislocation

• Overview
• Symptoms
• Treatment
• Prevention

Alternative Names:

Dislocation - knee cap; Patellar dislocation or instability

First Aid:

Splint (stabilize) the knee with the leg fully extended (straight), and see medical attention.

Your health care provider will examine the knee, which could provide confirmation of the dislocated knee cap. The knee cap will move incorrectly when touched.

A knee x-ray and, sometimes, MRIs should be done to make sure that the dislocation did not cause a bone to break or cartilage to be damaged. If tests show that you have no such damage, your knee will be placed into an immobilizer or cast to prevent you from moving it for several weeks (usually about 3 weeks). After this time, physical therapy is done to help build back your muscle strength and improve the knee's range of motion.

If the knee remains unstable, surgery may be necessary to stabilize the knee cap. This may be done using arthroscopic or open surgery.

Call immediately for emergency medical assistance if:

Call your health care provider if you injure your knee and symptoms of dislocation occur.

Call your health care provider if you are being treated for a dislocated knee and you notice increased instability in your knee, if pain or swelling return after they initially subsided, or if your injury does not appear to be resolving with time.

Also call if you re-injure your knee.

• Review Date: 9/21/2006
• Reviewed By: Jeffrey Kauffman, MD, Sacramento Knee and Sports Medicine, Sacramento, CA. Review provided by VeriMed Healthcare Network.

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