First-Time Dislocation: How to Deal with It

Abstract

First-time (primary) patellar dislocation commonly occurs in the young physically active population and is associated with a high rate of recurrent patellar instability [1–3]. Previous studies have demonstrated that the incidence of primary patellar dislocation is between 30 and 70 per 100,000 among children and teenagers [1, 4–7]. Primary patellar dislocation results in medial patellofemoral ligament (MPFL) injury [8–10], the major soft tissue stabilizer of the patella [9], which may lead to recurrent patellar instability. Recurrent patellar dislocation may require surgical correction. Acute patellar dislocation occasionally has concomitant osteochondral fracture, which requires surgery [8, 10–12]. The variation in location of injury of the MPFL and the varying presence of predisposing factors for recurrent patellar dislocation, such as trochlear dysplasia and patella alta, makes challenges in clinical decision-making between nonoperative and operative treatment [3, 12–14]. Although nonoperative management for primary patellar dislocation without osteochondral fracture is generally favored, current evidence suggests that not all primary dislocations should undergo the same treatment. Whereas MPFL reconstruction has been established as the golden standard for a soft tissue surgical procedure, the need to perform additional bony corrections is not yet known. Individualized analysis of risk for recurrence is advocated including meticulous physical examination and sufficient imaging modalities to recognize the first-time dislocators with high risk of recurrence.