The levator ani as an abdominal (pelvic floor) muscle forms the diaphragm of the pelvic cavity, supporting the bladder, uterus/prostate, and rectum. Its abdominal component is the primary muscular support for the pelvic organs and the key muscle in pelvic floor dysfunction rehabilitation.
| Origin | Pubic body and posterior surface of pubic ramus (pubococcygeus); Ischial spine and arcus tendineus (iliococcygeus); Coccyx (ischiococcygeus/coccygeus — sometimes grouped separately) |
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| Insertion | Perineal body, anococcygeal raphe, coccyx, walls of pelvic viscera |
| Nerve Supply | Inferior rectal nerve (S3, S4); Pudendal nerve branches |
| Blood Supply | Inferior vesical artery; Middle rectal artery |
| Actions | Supports the pelvic floor against intra-abdominal pressure; Lifts the anorectal junction during voluntary continence; Draws the rectum forward during defaecation (puborectalis) |
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Levator ani dysfunction underlies the pelvic floor disorders — stress urinary incontinence, pelvic organ prolapse, and obstructed defaecation — affecting one in three women. Pelvic floor physiotherapy targets levator ani coordination, strength, and relaxation. Levator ani avulsion from the pubic bone (detectable by MRI as a muscle defect) occurs in 10-30% of vaginal deliveries and increases prolapse risk three-fold.
Not directly palpable. Assessed by bimanual pelvic examination, transperineal or endovaginal ultrasound, and pelvic MRI.
Unilateral or bilateral levator ani avulsion from the pubic bone during vaginal delivery producing loss of central pelvic floor support, detectable as a muscle defect on MRI and associated with three-fold increased pelvic organ prolapse risk.
