Course: It originates on the lateral border of the ischial tuberosity of the ischium of the pelvis. From there, it passes laterally to its insertion on the posterior side of the head of the femur: the quadrate tubercle on the intertrochanteric crest and along the quadrate line, the vertical line which runs downward to bisect the lesser trochanter on the medial side of the femur. Along its course, quadratus is aligned edge to edge with the inferior gemellus above and the adductor magnus below, so that its the upper and lower borders run horizontal and parallel. At its origin, the upper margin of the adductor magnus is separated from it by the terminal branches of the medial femoral circumflex vessels. A bursa is often found between the front of this muscle and the lesser trochanter. Sometimes absent. | 
