Obturator internus muscle

The obturator internus muscle covers the obturator membrane and foramen, its muscle belly can be seen on the internal surface of the pelvis, while the tendon exits the lesser sciatic foramen to reach the femur.

Action: Lateral rotation of  femur

Innervation: Nerve to obturator internus

Origin: Posterior surface of obturator membrane and edges of surrounding bones: inferior pubic ramus and ischium

Insertion: Greater trochanter of femur