The Posterolateral Corner of the Knee

Abstract

Posterolateral corner injuries are common but often missed and should be considered as part of any standard diagnostic knee assessment. The primary posterolateral corner structures consist of the fibular (lateral) collateral ligament, popliteus tendon, and popliteofibular ligament and are typically reconstructed during a complete posterolateral corner reconstruction procedure. Other posterolateral corner structures that contribute to static stability include the posterolateral joint capsule, coronary ligament, oblique popliteal ligament, fabellofibular ligament, and lateral meniscus posterior horn. In addition, posterolateral corner structures that contribute to dynamic stability include the popliteus muscle, iliotibial band, biceps femoris muscle, and lateral gastrocnemius tendon. Due to the complex anatomy of this region, diagnostic magnetic resonance imaging (MRI) is often ordered when a posterolateral corner injury is suspected. The results of MRI can then be used to aid in preoperative treatment planning and to correlate pathology found during open or arthroscopic procedures with changes observed on imaging. The purpose of this chapter is to present three cases that illustrate correlations between MRI and arthroscopy in order to facilitate better diagnosis and treatment planning in patients with posterolateral corner and associated injuries.