Musculus coccygeus
The coccygeus (also called the caudal levator) is a broad muscle of the pelvic floor. It originates from the ischiatic spine of the pelvis and inserts on the transverse processes of the first several caudal vertebrae. Its actions include drawing the tail laterally and ventrally, compressing the pelvic floor, and contributing to support of the pelvic organs. It is innervated by branches of the pudendal and caudal rectal nerves (roughly S3–S5). It works with other pelvic-floor and tail muscles. Isolated injury is uncommon, but it can be affected by sacral or pelvic trauma, foaling injuries, or neurologic disease that reduces tail tone.
Origin: Ischiatic spine of the pelvis
Insertion: Transverse processes of the first several caudal vertebrae
Action: Draws the tail laterally; compresses the pelvic floor; supports pelvic organs
Innervation: Pudendal and caudal rectal nerves (S3-S5)
Reduced tail tone or inability to move the tail laterally can involve the coccygeus along with other muscles and their nerve supply. Perineal or sacral trauma may affect it. It is part of the clinical assessment of tail function and pelvic-floor integrity.
## Overview Pelvic floor weakness after foaling results from stretching or tearing of the coccygeus and surrounding muscles during a difficult birth. Mares may show reduced tail tone, difficulty defe
A horse that cannot swish its tail normally or that shows incontinence or hind-limb weakness after foaling or a fall should be examined. Do not pull on the tail of a neurologic horse.
## Overview Pelvic floor weakness after foaling results from stretching or tearing of the coccygeus and surrounding muscles during a difficult birth. Mares may show reduced tail tone, difficulty defecating, pneumovagina (wind-sucking), perineal laxity, and in severe cases risk of rectal prolapse. ## Causes Trauma during parturition. ## Diagnosis Clinical examination of tail tone, perineal conformation, and vaginal integrity. ## Treatment Time and controlled exercise for mild cases. Surgical repair (Caslick’s or more extensive reconstruction) for significant perineal or vaginal damage. ## Recovery and Prognosis Good for mild stretching. Surgical cases do well with proper repair. ## Prevention Assistance with difficult foalings when needed. Signs include: reduced tail tone; difficulty with defecation; pneumovagina; perineal laxity; rectal prolapse risk in severe cases
Reduced tail tone or inability to move the tail laterally can involve the coccygeus along with other muscles and their nerve supply. Perineal or sacral trauma may affect it. It is part of the clinical assessment of tail function and pelvic-floor integrity.
A horse that cannot swish its tail normally or that shows incontinence or hind-limb weakness after foaling or a fall should be examined. Do not pull on the tail of a neurologic horse.
See the Coccygeus (Caudal Levator) on our interactive 3D horse model. Open 3D Model