Management of Lateral-Sided Ligamentous Laxity and Posterolateral Corner

Combined anterior cruciate ligament and posterolateral injury of the knee can result in significant functional instability for the affected individual. Both components of the instability must be treated to maximize the probability of success for the surgical procedure. Higher failure rates of anterior cruciate ligament reconstruction have been reported when the posterolateral instability has been left untreated. There are varying degrees of posterolateral instability with respect to pathologic external tibial rotation and varus laxity. Surgical treatment of posterolateral instability (PLI) must address all components of the PLI (popliteus tendon, popliteofibular ligament, lateral collateral ligament, and the lateral-posterolateral capsule), the abnormal planes of motion, as well as other structural injuries. Successful anterior cruciate ligament surgery depends upon recognition and treatment of posterolateral corner injuries.