Medial Patellofemoral Ligament Reconstruction: Indications, Technique, and Outcomes.

ABSTRACT

The medial patellofemoral ligament is the primary static restraint to lateral patellar translation. It is injured in 96% to 100% of patellar dislocations that affect approximately 6 to 29 of 100,000 patients and is more common in patients younger than 20 years of age. Risk factors for patellar dislocation include patella alta, trochlear dysplasia, genu valgus, increased Q angle, and hyperlaxity. The treatment for patellar instability depends on the clinical and radiographic findings and can be nonoperative for first-time dislocations (bracing, proximal strengthening, and progressive return to sport) or operative for recurrent dislocations. It is critical for medial patellofemoral ligament reconstruction to reproduce the anatomy and isometry of the native ligament. Graft choice and methods of fixation are less critical to achieve successful outcomes. Studies have reported successful outcomes and improved Kujala scores, with recurrent instability ranging from 1% to 5%. Careful surgical technique can avoid complications, including fracture, graft failure, loss of range of motion, persistent anterior knee pain, medial instability, and recurrent instability. The role of the medial quadriceps tendon femoral ligament also should be considered more in future research.