The gemellus superior and gemellus inferior are located in the human leg. These muscles lie parallel to the obturator internus muscle in the gluteal region. The two gemelli bound to the sides of the obturatur internus muscle. Like the obturator internus muscle, the gemellus superior and gemellus inferior help to steady the femoral head in the acetabulum. Both muscles also help to laterally rotate the extended thigh and abduct the flexed thigh at the hip. Gemellus superior emerges from the spine of the ischium. The ischium is one of the three bones that form the hip bone. The other two bones are the ilium and pubis. Meanwhile, gemellus inferior emerges from the ischial tuberosity. Both muscles insert on the middle of the greater trochanter of the femur. The two gemelli vary in size, but gemellus superior is usually smaller than gemellus inferior. Gemellus inferior is innervated by a branch of the nerve to the quadratus femoris. Meanwhile, gemellus superior is supplied by the nerve to the obturator internus muscle.
Written and medically reviewed by the Healthline Editorial Team
In Depth: Gemellus superior