The iliotibial band (ITB) is the lateral portion of the deep fascia of the thigh which extends from the iliac crest to the lateral tibial tubercle, known as Gerdy's :iibercle.' It is described as an extremely sirong, thickened strip of fascia lata which receives tendinous reinforcements from the tensor fascia lata and the lateral fibres of gluteus maximus and serves to support the Knee on its lateral aspect.2 According to Schafer, since the ITB crosses both the hi joint and the knee joint, its affect on the knee is dictated by the position of the hip.

When flexed, the knee depends upon muscular support laterally by me ] TB and biceps femoris; medially by sanorius, gracilis, semimembranosis and semitendinosis, anteriorly by quadriceps femoris; and posteriorly by poplkeus. The ITB locks the knee into extension diereby providing maximum stability with minimal effort. It has been suggested that the ITB appeared phylogenetically with the development of upright posture.3 Iliotibial Band Friction Syndrome (ITBFS) occurs as a result of friction generated between he disral ITB and the lateral femoral conay ie. Successive flexion /extension of the knee induces this "over use or misuse syndrome" as the ITB moves from its anterior position in relation to the femoral condyle during knee extension to a posterior position in flexion.4 It has been suggested that the discomfort experienced in the ITBFS may originate from contracture of the ITB irself, its insertion into Gerdy's tubercle, the bursa overlying the lateral femoral condyle or the periosteum.