Corpus: External obturator muscle
Synonym: obturator externus muscle
1. Definition
The external obturator muscle is a flat, triangular skeletal muscle that belongs to the deep hip muscles. Some authors also categorize it as an adductor muscle.
2. Course
2.1. Origin
The external obturator muscle originates along the lateral aspect of the obturator foramen, from the outer surface of the obturator membrane and its bony frame, including the pubic branch and the inferior branch of the ischium.
2.2. Appendix
The fibers of the external obturator muscle run dorsally, laterally, and cranially. They converge into a tendon that crosses the neck of the femur dorsally and attaches to the trochanteric fossa of the femur.
3. Innervation
The external obturator muscle is innervated by the obturator nerve.
4. Function
Contraction of the external obturator muscle causes external rotation of the thigh and also assists in the adduction of the thigh.