levator ani


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Related to levator ani: Levator ani syndrome, Coccygeus, Puborectalis

levator ani

one of a pair of muscles of the pelvic diaphragm that stretches across the bottom of the pelvic cavity like a hammock, supporting the pelvic organs. It is a broad thin muscle that separates into the pubococcygeus and the iliococcygeus. It originates from the ramus of the pubic bone, the spine of the ischium, and a band of fascia between the pubis and the ischium; it inserts into the last two segments of the coccyx, the anococcygeal raphe, the sphincter ani externus, and the central tendinous point of the perineum. The left and right levator ani muscles are divided ventrally but converge as a single sheet across the midline dorsally, forming most of the pelvic diaphragm. The levator ani is innervated by branches of the pudendal plexus, which contains fibers from the fourth sacral nerve. It functions to support and slightly raise the pelvic floor. The pubococcygeus draws the anus toward the pubis and constricts it. Compare coccygeus.

levator ani

A broad, thin, flat muscle, located on the pelvic sidewall, which forms the pelvic diaphragm when joining with its twin. It supports the pelvic viscera and surrounds the structures that pass through it.

Artery
Inferior gluteal artery.

Nerve
Pudendal, perineal and inferior rectal nerves, sacral spinal nerves (S3, S4).

Origin
Inner sidewall of the lesser pelvis.

Insertion
Coccyx, levator ani of opposite side, and structures that pass through it.
 
Pronunciation 
Medspeak-UK: pronounced, leh VAY tore ANN ee
Medspeak-US: pronounced, LEH vuh tore ANN ee

levator ani

A broad muscle that helps to form the floor of the pelvis.
See also: levator
References in periodicals archive ?
An example of this predicament is illustrated by the 'pelvic clock exam', where it is suggested that the levator ani muscle is externally palpable in the anal triangle (Kotarinos, Herman and Wallace, 1997).
A retrospective study of 987 women referred to a pelvic pain clinic at the University of North Carolina, Chapel Hill, for chronic pelvic pain, found levator ani tenderness in 22% and piriformis tenderness in 13% of the 942 of patients evaluated for those conditions.
In this phase, a standardized protocol using ventral prostate, seminal vesicles with coagulating glands, levator ani and bulbocavernosus muscle complex, Cowper's glands, and glans penis was successfully tested against a reference androgen compound, testosterone propionate (TP), and a reference antagonist, flutamide (OECD 2001).
Initial EMG studies were performed on 58 primiparous women in the early third trimester, providing baseline data on muscle function at four separate sites of the levator ani.
The fact that the PB can move backward 3-4 cm toward the sacrum when a weighted speculum is placed in the posterior vagina likewise indicates that the position of the PB is determined by the levator ani muscle rather than by any inherent importance of its own.
Enter the rectovaginal space and dissect deeply and widely to permit visualization of the medial fascia of the levator ani muscles laterally on both sides.
The endopelvic fascia and ligaments that attach the pelvic organs to the pelvic sidewalls form the passive support, supporting pelvic organs without tension when the pelvic floor is closed by healthy levator ani muscles.
Of the 212 patients with levator ani tenderness, 23% had no previous surgeries, 61% had one to three surgeries, and 17% had more than three surgeries, compared with 30%, 60%, and 10%, respectively, of those without levator ani tenderness.
The study comprises the largest series reported on patients who underwent total colpocleisis with levator ani plication, he said at the annual meeting of the American Urogynecologic Society.
SAN FRANCISCO--Having an operative vaginal delivery nearly quadrupled a woman's risk of developing an abnormality of the levator ani muscle--an important muscle for pelvic organ support--in a study of 280 women.
Vaginismus results from involuntary spasm of the levator ani and perineal muscles of the outer third of the vagina.