Tensor fascia latae and gluteal muscles myoelectric responses to increasing levels of hip medial rotation torque.

Medial hip rotation is typically attributed to the tensor fascia latae (TFL) and lateral rotation, to the gluteus maximus. However, experimental studies in cadavers suggest that the TFL lacks a moment arm for medial rotation and that the gluteus maximus may act as hip medial rotator depending on the hip flexion angle. In order to address this contradictory thinking, we measured the myoelectric activity of TFL, gluteus medius and gluteus maximus (superior portion, GMaxS, and inferior portion, GMaxI) for increasing levels of medial rotation torque applied to the hip.