Inferior gemellus

The inferior gemellus (Latin: musculus gemellus inferior) is a small pelvic muscle that stretches between the ischium of the hip bone and femur. It is located inferior to the gluteal muscles and deep within the posterior pelvis. Therefore, it belongs to the deep gluteal muscle group. Also, as the inferior gemellus provides external (lateral) rotation of the thigh, it is classified as one of the lateral rotators. Together with the superior gemellus and obturator internus muscles, it forms a muscle complex known as the triceps coxae.

Origin

The inferior gemellus muscle originates from the ischial tuberosity.

Insertion

The inferior gemellus inserts on the medial surface of the greater trochanter (of the femur) via the tendon of the obturator internus muscle.

Action

The inferior gemellus muscle provides external (lateral) rotation of the femur at the hip joint.

Innervation

The inferior gemellus is innervated by the nerve to quadratus femoris (L5, S1) that arises from the sacral plexus.

Blood supply

The inferior gemellus muscle receives arterial blood supply from the medial circumflex femoral and inferior gluteal arteries. The first artery is a branch of the deep femoral artery, while the latter arises from the internal iliac artery.