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Pelvic floor
Left Levator ani from within.
Coronal section through the anal canal. B. Cavity of urinary bladder V.D. Ductus deferens. S.V. Seminal vesicle. R. Second part of rectum. A.C. Anal canal. L.A. Levator ani. I.S. Sphincter ani internus. E.S. Sphinear ani externus.
Latin	diaphragma pelvis
Gray's	subject #119 420
Nerve	Sacral nerves 3-4 [1]
Dorlands/Elsevier	d_15/12293527

The pelvic floor or pelvic diaphragm is composed of muscle fibers of the levator ani, the coccygeus, and associated connective tissue which span the area underneath the pelvis. The pelvic diaphragm is a muscular partition formed by the levatores ani and coccygei, with which may be included the parietal pelvic fascia on their upper and lower aspects. It separates the pelvic cavity above from the perineal region below.

The right and left levator ani lie almost horizontally in the floor of the pelvis, separated by a narrow gap that transmits the urethra, vagina, and anal canal. The levator ani is usually considered in three parts: pubococcygeus, puborectalis, and iliococcygeus. The pubococcygeus, the main part of the levator, runs backward from the body of the pubis toward the coccyx and may be damaged during parturition. Some fibers are inserted into the prostate, urethra, and vagina. The right and left puborectalis unite behind the anorectal junction to form a muscular sling . Some regard them as a part of the sphincter ani externus. The iliococcygeus, the most posterior part of the levator ani, is often poorly developed.

The coccygeus, situated behind the levator ani and frequently tendinous as much as muscular, extends from the ischial spine to the lateral margin of the sacrum and coccyx.

The pelvic cavity of the true pelvis has the pelvic floor as its inferior border (and the pelvic brim as its superior border.)

Some sources do not consider the "pelvic floor" and "pelvic diaphragm" to be identical, with the "diaphragm" consisting of only the levator ani and coccygeus, while the "floor" also includes the perineal membrane and deep perineal pouch.^[2] However, other sources include the fascia as part of the diaphragm. ^[3] In practice, the two terms are often used interchangeably.

Inferiorly, the pelvic floor extends into the anal triangle.

Contents 1 Function 2 Clinical significance 3 See also 4 Additional images 5 References 6 External links

It is important in providing support for pelvic viscera (organs), e.g. the bladder, intestines, the uterus (in females), and in maintenance of continence as part of the urinary and anal sphincters.

In women, the levator muscles or their supplying nerves can be damaged in pregnancy or childbirth. This occurs more commonly after a normal vaginal delivery, but can also occur following a c-section. There is some evidence that these muscles may also be damaged during a hysterectomy. Pelvic floor exercises, also known as Kegel exercises, may improve the tone and function of the pelvic floor muscles, which is of particular benefit for women (and less commonly men) who suffer from urinary incontinence. In addition to preventing or diminishing leakage it may improve vaginal laxity, and consequent diminished sexual sensation.

Damage to the pelvic floor not only contributes to urinary incontinence but can lead to pelvic organ prolapse. Pelvic organ prolapse occurs women when pelvic organs (e.g. the vagina, bladder, rectum, or uterus) protrude into or outside of the vagina. The causes of pelvic organ prolapse are not unlike those that also contribute to urinary incontinence. These include inappropriate (asymmetrical, excessive, insufficient) muscle tone and asymmetries caused by trauma to the pelvis. Age, childbirth, family history, and hormonal status all contribute to the development of pelvic organ prolapse. The vagina is suspended by attachments to the perineum, pelvic side wall and sacrum via attachments that include collagen, elastin, and smooth muscle. Repair of lost vaginal support may involve surgery.

• Pubococcygeus muscle
• Postpartum pelvic floor dysfunction

Coronal section of pelvis, showing arrangement of fasciæ. Viewed from behind.	The arteries of the pelvis.	Iliac colon, sigmoid or pelvic colon, and rectum seen from the front, after removal of pubic bones and bladder.	Male pelvic organs seen from right side.

1. ^ Human anatomy at Dartmouth part_6/chapter_37.html#chpt_37_innervation_diaphragm
2. ^ (2005) Gray's Anatomy For Students, 391. 
3. ^ Pelvic+diaphragm at eMedicine Dictionary

• Overview at nih.gov
• Selection of recent medical literature continuously updated on Pelvic Floor Functional Anatomy

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.

v • d • e General anatomy of torso
Thorax/ Thoracic cavity	Mediastinum (Superior, Anterior, Middle, Posterior) • Superior thoracic aperture • Inferior thoracic aperture • Triangle of auscultation • Intercostal space • Thoracic plane • Thoracic wall/Thoracic cage - fascia (Pectoral fascia, Clavipectoral fascia, Thoracolumbar fascia) • Chest • Midsternal line
Thoracic diaphragm	openings (Caval opening, Esophageal hiatus, Aortic hiatus, Foramina of Morgagni) • Central tendon • Crus of diaphragm • arcuate ligaments (Lateral, Medial, Median)
Abdomen/ Abdominal cavity	Retroperitoneum • Paracolic gutters • Hepatobiliary triangle anterior abdominal wall (Arcuate line, Linea alba, Tendinous intersection, Linea semilunaris, McBurney's point, Traube's space, Inguinal triangle) • Inguinal canal (Deep inguinal ring, Superficial inguinal ring, Intercrural fibers, Crura of superficial inguinal ring) • Lumbar triangle • regions (Epigastrium, Hypochondrium, Umbilical region, Latus, Hypogastrium, Inguinal region) • planes (Transpyloric plane, Intertubercular plane, Midclavicular line) fascia (Fascia of Camper, Fascia of Scarpa, Transversalis fascia, Renal fascia, Rectus sheath)
Pelvis/ Pelvic cavity	Pelvic floor • Retropubic space fascia (Pelvic fascia, Superior fascia of diaphragm of pelvis, Inferior fascia of diaphragm of pelvis, Fascia of the Obturator internus, Tendinous arch, Iliac fascia)
Perineum	Anal triangle (Ischioanal fossa, Pudendal canal, Anococcygeal raphe) Urogenital triangle (Superficial perineal pouch, Deep perineal pouch) Perineal body fascia (Dartos/fascia of perineum/superficial perineal fascia/Fascia of Colles, Perineal membrane/"Inferior fascia of UGD", "Superior fascia of UGD")

v • d • e List of muscles of torso
BACK	splenius (capitis, cervicis) - erector spinae (iliocostalis, longissimus, spinalis) - latissimus dorsi transversospinales: (semispinalis dorsi, semispinalis cervicis, semispinalis capitis, multifidus, rotatores) - interspinales - intertransversarii
SUBOCCIPITAL	rectus capitis posterior (major, minor) - obliquus capitis (inferior, superior)
CHEST	intercostales (external, internal, innermost) - subcostales - transversus thoracis - levatores costarum - serratus posterior (inferior, superior) - diaphragm
ABDOMEN	anterior/lateral wall: obliques (external, internal) - transversus abdominis - rectus abdominis - pyramidalis posterior wall: quadratus lumborum - psoas major/psoas minor - iliacus cremaster
PELVIS/FLOOR	levator ani (iliococcygeus, pubococcygeus, puborectalis) - coccygeus
PERINEUM	anal triangle: sphincter ani (externus, internus) superficial perineal pouch (superficial transverse perineal, bulbospongiosus, ischiocavernosus) deep perineal pouch (deep transverse perineal, sphincter urethrae membranaceae)