Muscles / Core
External anal sphincter
- Core
- Pelvic floor
- Deep layer
Anatomy
- Origin
- Skin and fascia around the anus; coccyx via the anococcygeal ligament
- Insertion
- Perineal body
- Nerve
- Inferior anal (rectal) nerve, branch of the pudendal nerve (S2-S4)
Actions
- Constricts the anal canal (voluntary continence)
- Supports the perineal body
References (4)
- Standring S, ed. Elsevier. Gray's Anatomy: The Anatomical Basis of Clinical Practice. 42nd ed.
- Dalley AF, Agur AMR. Wolters Kluwer. Moore's Clinically Oriented Anatomy. 9th ed.
- Neumann DA. Elsevier. Kinesiology of the Musculoskeletal System: Foundations for Rehabilitation. 3rd ed.
- Betts JG, Young KA, Wise JA, et al. OpenStax (free, openly licensed textbook). Anatomy and Physiology 2e