The action of the muscles associated with the ITB (tensor fasciae latae and some fibers of gluteus maximus) flex, extend, abduct, and laterally and medially rotate the hip.

The tensor fasciae latae effectively tightens the iliotibial band around the area of the knee.

ITB syndrome can also be caused by poor physical condition, lack of warming up before exercise, or drastic changes in activity levels.

Other risk factors for ITBS include gait abnormalities such as overpronation, leg length discrepancies, or bow-leggedness.

The most vulnerable range of knee flexion for this condition is at 30-40 degrees; this is where the ITB crosses the lateral femoral epicondyle.