Patellar dislocation is a painful and distressing event, when the patella jumps clean out of the restraining walls of the groove in which it normally rides.

Management of patellar dislocation
A first event may be managed conservatively, with a period of immobilisation, after which sports may be limited for some months. If there is a subsequent event, the patient is usually subjected to a full investigation of any underlying causes and surgery may be planned. This may include a reconstruction of the MPFL. In patients where there is a marked problem with the anatomy, such as trochlear dysplasia, corrective surgery may be undertaken.
FORUM DISCUSSIONS
Dislocated my patella 4 weeks ago.
Patella dislocation - what to expect and return to work
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CLINICAL PUBLICATIONS
Primary traumatic patellar dislocation. Tsai C-H, Hsu C-J, Hung C-H and Hsu H-C. J Orthop Surg Res. 2012; 7: 21.
Medial marginal fracture of the patella following patellar dislocation. Toritsuka Y, Horibe S, Hiro-Oka A, Mitsuoka T and Nakamura N. Knee. 2007 Dec;14(6):429-33. Epub 2007 Sep 19.
Femoral avulsion of the medial patellofemoral ligament after primary traumatic patellar dislocation predicts subsequent instability in men: a mean 7-year nonoperative follow-up study. Sillanpää PJ, Peltola E, Mattila VM, Kiuru M, Visuri T and Pihlajamäki H. Am J Sports Med. 2009 Aug;37(8):1513-21. doi: 10.1177/0363546509333010. Epub 2009 Apr 17.