Origin Ischial spine Insertion Medial surface of greater trochanter of femur, in common with obturator internus Action Rotates the thigh laterally; also helps abduct the flexed thigh Innervation Nerve to the obturator internus and superior gemellus -- a branch of the sacral plexus (L5, S1) (L5, S1) Arterial Supply Inferior gluteal artery