In this Section
The LCL / PLC, Injuries, and Surgery
The lateral collateral ligament (LCL) is one of the four major ligaments of the knee. It is located on the outside (lateral side) of the knee and connects the femur to the fibula. It is part of a larger group of complex structures referred to as the posterolateral corner (PLC). Other important structures in the posterolateral corner are the popliteus tendon, biceps femoris tendon, and the popliteofibular ligament. The LCL and PLC structures provide stability and prevent the outside of the knee from opening up with walking and other movements. They also play an important role in the rotational stability of the knee.
The most common symptom following an injury to the LCL and PLC is pain over the outside of the knee. Swelling, decreased motion, and instability are also common with this injury. It may also become difficult to place weight on the knee.
Partial tears of the LCL and PLC structures can be treated without surgery, but complete tears usually require surgical treatment. The torn ligaments can sometimes be repaired (sewn back together) or are reconstructed using a tendon graft obtained from either the patient or a cadaver (allograft). If other ligaments are also injured in the knee (ACL, MCL, or PCL), these can be surgically addressed at the same time.