Traumatic patellar dislocation in children and adolescents: treatment update and literature review

Traumatic patellar dislocation in children and adolescents is a complex problem resulting from a range of anatomic and mechanical conditions. A careful review of the literature demonstrates certain risk factors that predispose children to recurrent dislocation. With this understanding, these conditions can be managed more aggressively in the hope of an improved outcome. Additionally, a vast number of surgical procedures to correct patellar instability have been described, and recent cadaveric studies are now guiding surgical interventions.

Risk factors for recurrent dislocation may include various skeletal abnormalities, increased quadriceps angle, generalized ligamentous laxity, and family history. Recent anatomic and biomechanical studies have demonstrated that the medial patellofemoral ligament and the vastus medialis obliquus are the primary restraints to lateral translation and ultimately dislocation of the patella. Management should therefore be directed both at correcting anatomic abnormalities when indicated and at reconstruction of medial restraints to patellar tracking.

The recommendation for management of a traumatic patellar dislocation in a skeletally immature patient is initially conservative, emphasizing early motion and quadriceps strengthening. However, in patients for whom conservative management has failed or who are at particularly high risk for dislocation and require surgical intervention, repair or reconstruction of the medial patellofemoral ligament is the treatment of choice. Recent works have included investigation of less invasive techniques in children.