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Dislocation - kneecap; Patellar dislocation or instability
If you can, straighten out the knee. If it is stuck and painful to move, stabilize (splint) the knee and get medical attention.
Your health care provider will examine the knee, which could confirm that the kneecap is dislocated.
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 can help build back your muscle strength and improve the knee's range of motion.
If the knee remains unstable, you may need surgery to stabilize the kneecap. This may be done using arthroscopic or open surgery.
Call your health care provider if you injure your knee and have symptoms of dislocation.
Call your health care provider if you are being treated for a dislocated knee and you notice:
Also call if you re-injure your knee.
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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