Summary
Origins
- Internal surface of the obturator membrane and surrounding pelvic bones
Insertions
- Medial surface of the greater trochanter of the 🦴 femur
Actions
- Laterally rotates the hip
- Abducts the flexed thigh
- Stabilizes the femoral head in the acetabulum
The obturator internus lines the inner pelvis, exits through the lesser sciatic foramen, and makes a right-angle turn to reach the greater trochanter. Its cordlike tendon partners with the gemelli to laterally rotate the hip and clamp the femoral head into the socket.