sartorius /särtôr″ē·əs/ [L, sartor, tailor] , the longest muscle in the body, extending from the pelvis to the calf of the leg. It is a narrow ribbon-shaped muscle that arises from the anterior superior iliac spine, passes obliquely across the proximal anterior part of the thigh from the lateral to the medial side, and inserts into the tibia. It acts to flex the thigh and rotate it laterally and to flex the leg and rotate it medially. Compare quadriceps femoris.
