The obturator externus muscle is one of the 6 muscles of the medial compartment of the thigh. The obturator externus is a flat fan-shaped muscle which attaches to the outer aspect of the obturator membrane (the obturator internus attaches on the inner surface).
The medial compartment of the thigh includes the following 6 muscles:
- Pectineus
- Gracilis
- Adductor longus
- Adductor brevis
- Adductor magnus
- Obturator externus
Origin
- External surface of the obturator membrane
- Adjacent borders of the obturator foramen
Insertion
- Trochanteric fossa (posteromedial surface of greater trochanter of femur)
Action
- Lateral rotation of hip
- Assists hip adduction
Innervation
- Obturator nerve: L2, L3, L4
Blood Supply
- Obturator artery
- Medial circumflex femoral artery