Obturator internus - Anatomy

Origin	Internal surface of obturator membrane and posterior bony margins of obturator foramen
Insertion	Medial surface of greater trochanter of femur, in common with superior and inferior gemelli
Action	Rotates the thigh laterally; also helps abduct the thigh when it is flexed
Innervation	Nerve to the obturator internus and superior gemellus -- a branch of the sacral plexus (L5, S1) (L5, S1)
Arterial Supply	Internal pudendal and superior and inferior gluteal arteries