Acute Patellar Dislocation (First-Time Dislocator)
Patellar dislocation most commonly occurs in the adolescent female population. Trochlear dysplasia is the most predictive risk factor for recurrence after first-time dislocation. Other factors include patellar height, young age and/or open physes, patella alta, high TT-TG distance, rotational malalignment, and patient factors such as ligamentous laxity and jumping/landing mechanics. The medial patellofemoral ligament complex is injured in the vast majority of patients after patellar instability, and chondral/osteochondral injuries are also common. The standard of care for first-time dislocators has historically been non-operative, unless a loose osteochondral body is discovered on imaging. The recent literature has identified young patients with trochlear dysplasia as a high-risk group for recurrence, however, prompting increased attention to treatment options. MPFL repair is thought to be acceptable only when the injury to the ligament is discrete, and controversy exists regarding its efficacy. MPFL reconstruction has become the standard of care intervention for first-time dislocations when surgery is indicated.
KeywordsPatellofemoral Instability Knee
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