Medial patellofemoral ligament anatomy: is it a predisposing factor for lateral patellar dislocation?

Purpose: Because the medial patellofemoral ligament (MPFL) is the primary restraint to lateral dislocation of the patella, we aimed, in this controlled study, to verify whether the MPFL with different measurements could be considered another predisposing factor for patellar dislocation.

Methods: A group of 100 consecutive individuals without the criteria for patellar dislocation (trochlear dysplasia, patella alta and lateral patellar tilt) was recruited as a control group and underwent magnetic resonance imaging (MRI) study and another group of 50 patients with patellar instability. Femoral condyles, interepicondylar distance, length and thickness of the MPFL were measured.