Posterolateral knee injuries

The posterolateral corner (PLC) of the knee is a complex area of the knee formed by the interaction of multiple structures. Injuries to the posterolateral corner can be debilitating to patients and require prompt recognition and treatment to avoid long term consequences. Injuries to the PLC often occur in combination with other ligamentous injuries to the knee; most commonly the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL). As with any injury, an in-depth understanding of the anatomy and functional interactions of the posterolateral corner is critical to diagnosing and treating injuries here.

Anatomy and function

Structures found in the posterolateral knee include the tibia, fibula, lateral femur, iliotibial band (IT band), the long and short heads of the biceps femoris tendon, the fibular (lateral) collateral ligament (FCL), the popliteus tendon, the popliteofibular ligament, the lateral gastrocnemius tendon, and the fabellofibular ligament. It has been reported that among these, the 3 most important static stabilizers of the posterolateral knee are the FCL, popliteus tendon, and popliteofibular ligament Studies have reported that these structures work together to stabilize the knee by restraining varus, external rotation and combined posterior translation with external rotation to it.