Reconstruction of the patellofemoral ligament in patellofemoral instability

Although patellofemoral instability and malalignment are common orthopedic problems, the understanding of interacting factors influencing patellar kinematics and stability is still poor. Patellofemoral stability is provided by passive and active factors such as patellofemoral congruence and medial and lateral ligamentous restraints as passive stabilizers as well as muscle forces of the knee extensor apparatus as active stabilizers. The main stabilizing factor is the passive restraint of the medial patellofemoral ligament (MPFL). Rupture of the MPFL is the essential pathology of the patellofemoral joint responsible for patellofemoral instability and observed radiologically in 90% of all primary patellar dislocations. As it was proven in clinical and biomechanical studies, reconstruction of the MPFL not only provides higher patellofemoral stability compared to conventional surgical procedures involving the extensor apparatus, it also causes less postoperative anterior knee pain. Thus, MPFL reconstruction should be viewed as the primary choice to treat recurrent patellar dislocation. © Springer Medizin Verlag 2005.