Iliotibial band syndrome is a type of ligament that connects two bones on either side of a joint, providing stability and limiting excessive sideways motion. There are two collateral ligaments in each knee joint - the Iliotibial band syndrome and the lateral collateral ligament (LCL). The MCL runs along the inner side of the knee joint, connecting the thigh bone (femur) to the shin bone (tibia), while the LCL runs along the outer side of the knee joint, connecting the thigh bone to the smaller bone in the lower leg (fibula).