Muscle Actions and Functions – Anatomy and Movement Practice Test

Hip abduction means moving the thigh away from the midline. Of the muscles listed, piriformis is the one that can perform this action, but mainly when the hip is flexed. In a flexed hip, piriformis acts to abduct the thigh to help stabilize the femoral head in the socket; when the hip is extended it functions more as a lateral rotator. The other muscles here don’t abduct the hip—gracilis adducts the thigh, while tibialis anterior and extensor digitorum longus act on the foot. So, in a context describing hip abduction among these options, piriformis best fits the action.