Posterolateral corner of knee

The posterolateral corner (PLC) of the knee is a complex anatomical region composed of multiple ligamentous and tendinous structures that provide stability to the knee joint. The primary stabilizers of the PLC include the lateral collateral ligament (LCL), popliteus tendon, and popliteofibular ligament (PFL).[1-5]

Additional structures within the PLC include the arcuate ligament, fabellofibular ligament, oblique popliteal ligament, and the posterior meniscofemoral ligament. The popliteus muscle-tendon unit is also a significant component, with its attachments to the lateral meniscus and the PFL.[1-2][6][5]

The lateral collateral ligament originates from the lateral femoral epicondyle and inserts on the fibular head, providing varus stability. The popliteus tendon originates from the lateral femoral condyle and inserts on the posterior aspect of the tibia, playing a role in internal rotation and posterior stability. The popliteofibular ligament extends from the popliteus tendon to the fibular head, contributing to the stability against external rotation and posterior translation.[1-5]

Understanding the detailed anatomy and relationships of these structures is crucial for diagnosing and managing PLC injuries, which are often associated with cruciate ligament injuries and can lead to significant knee instability if not properly addressed.[3-5]