The iliotibial tract, also called the iliotibial band, is a long, wide, band of fascia that lies over the muscles on the outer surface of the thigh. It begins superiorly at the level of the greater trochanter of the femur (upper edge of the thigh bone) and ends inferiorly where it inserts in the condyle of the tibia. This band is a thickening of the normal fascia that surrounds the entire leg. It is thin medially (inner thigh), but is thick laterally (outer thigh). Acting almost like a ligament, this tendon helps mainly to stabilize the knee joint, but also acts in flexing (bending) and extending (straightening) the knee.
