Lateral collateral ligament (LCL)

The lateral collateral ligament (LCL) is a band of tough tissue on the outer side of your knee that connects the thigh bone (femur) to the smaller bone in your lower leg (fibula). It helps stabilize the knee joint by preventing excessive side-to-side movement, especially toward the outer side. The LCL is important for maintaining proper knee function during activities like walking, running, and jumping. An injury to this ligament, such as a sprain or tear, can cause pain, instability, and difficulty moving the knee normally. Proper diagnosis and treatment are essential for recovery.