Muscle
Obturator externus
Lateral rotator (medial thigh group)
High-yield
Obturator nerve (not a gluteal nerve); laterally rotates the thigh.
Overview
A deep muscle on the external obturator membrane that laterally rotates the hip; the only obturator-nerve-supplied lateral rotator.
Reference facts
- Origin
- External surface of the obturator membrane and margins of the obturator foramen
- Insertion
- Trochanteric fossa of the femur
- Action
- Laterally rotates the thigh; steadies the femoral head in the acetabulum
- Innervation
- Obturator nerve (L3, L4)
- Blood supply
- Obturator artery
Frequently asked questions
What does the obturator externus do?
The obturator externus laterally rotates the thigh; steadies the femoral head in the acetabulum.
What nerve innervates the obturator externus?
The obturator externus is innervated by the obturator nerve (L3, L4).
Where does the obturator externus attach?
The obturator externus originates from the external surface of the obturator membrane and margins of the obturator foramen and inserts on the trochanteric fossa of the femur.
What is the blood supply of the obturator externus?
The obturator externus is supplied by the obturator artery.