The iliotibial band is a thick band of tissue that runs from the pelvis down the outside of the femur (thigh bone) to just below the knee, where it connects to the tibia (shinbone). In iliotibial band syndrome (ITBS), the band becomes inflamed and painful at the outside of the knee due to rubbing against the knee joint when repeatedly bending and straightening the knee—movements typically made while running or cycling.
Treatment for ITBS is with rest and with ice packs and pain relievers to reduce inflammation and pain.