Perineum 83916 226178699 2008-07-17T04:53:29Z 99.153.133.223 /* Additional images */ {{mergefrom|Taint (slang)|Talk:Perineum#Merger proposal|date=January 2008}} {{Infobox Anatomy | Name = Perineum| Latin = | GraySubject = 120 | GrayPage = 424 | Image = Gray406.png | Caption = The muscles of the male perineum | Image2 = | System = | Artery = [[perineal artery]], [[dorsal artery of the penis]], [[deep artery of the penis]] | Vein = | Nerve = [[perineal nerve]], [[posterior scrotal nerves]], [[dorsal nerve of the penis]], [[dorsal nerve of clitoris]] | Lymph = primarily [[superficial inguinal lymph nodes]] | MeshName = | MeshNumber = | DorlandsPre = p_13 | DorlandsSuf = 12627677 | }} In [[human anatomy]], the '''perineum''' is generally defined as the surface region in both males and females between the [[pubic symphysis]] and the [[coccyx]]. The perineum is the region of the body inferior to the pelvic diaphragm and between the legs. A diamond-shaped area on the inferior surface of the trunk which includes the [[anus]] and, in females, the [[vagina]]<ref>Gray, Henry. Anatomy of the Human Body. Philadelphia: Lea & Febiger, 1918; Bartleby.com, 2000.</ref>. Its definition varies: it can refer to only the superficial structures in this region, or it can be used to include both superficial and deep structures. The perineum corresponds to the [[outlet of the pelvis]]. The '''anogenital distance''' is a measure of male feminisation measuring the distance between the [[anus]] and the base of the [[penis]]. Studies show that the perineum is twice as long in males as in females. <ref>Validity of anogenital distance as a marker of in utero phthalate exposure. PMID 16393642</ref> Measuring the anogenital distance in neonatal humans has been suggested as a noninvasive method to predict neonatal and adult reproductive disorders.<ref>Michelle Welsh, et al.: [http://www.jci.org/articles/view/34241 Identification in rats of a programming window for reproductive tract masculinization, disruption of which leads to hypospadias and cryptorchidism. J. Clin. Invest., 13 March 2008.]</ref> ==Boundaries== Its deep boundaries are as follows:<ref>{{NormanAnatomyFig|perineumboundaries}}</ref> * in front: the [[pubic arch]] and the [[arcuate ligament]] of the [[pubis (bone)|pubis]] * behind: the tip of the [[coccyx]] * on either side: the [[inferior pubic ramus|inferior rami of the pubis]] and [[Ischium]], and the [[sacrotuberous ligament]] In Alfred Kinsey's 1967 report, he concluded that the perineum was one of the 6 key [[erogenous zone]]s for males. ==Triangles== A line drawn transversely across in front of the [[tuberosity of the ischium|ischial tuberosities]] divides the space into two triangles: {| class="wikitable" | '''Name''' || '''Location''' || '''Contents''' |- | [[Urogenital triangle]] || the anterior triangle || in females, contains the [[vagina]] |- | [[Anal triangle]] || the posterior triangle || contains the [[anus]] |} ===Perineal fascia=== The terminology of the perineal [[fascia]] can be confusing, and there is some controversy over the nomenclature. This stems from the fact that there are two parts to the fascia, the superficial and deep parts, and each of these can be subdivided into superficial and deep parts. The layers and contents are as follows, from superficial to deep: * 1) [[Skin]] * 2) superficial perineal fascia: Subcutaneous tissue divided into two layers: (a) A superficial fatty layer, and (b) [[Colles' fascia]], a deeper, membranous layer. * 3) deep perineal fascia and muscles: {| class="wikitable" | [[superficial perineal pouch]] || Contains superficial perineal muscles: [[Transversus perinei superficialis muscle|transversus perinei superficialis]], [[Bulbospongiosus muscle|bulbospongiosus]], [[Ischiocavernosus muscle|ischiocavernosus]] |- | inferior fascia of [[urogenital diaphragm]], or [[perineal membrane]] || A membranous layer of the [[deep fascia]]. |- | [[deep perineal pouch]] || Contains the deep perineal muscles: [[transversus perinei profundus muscle|transversus perinei profundus]], [[Sphincter urethrae membranaceae muscle|sphincter urethrae membranaceae]] |- | [[superior fascia of the urogenital diaphragm]] || Considered hypothetical by some modern anatomists, but still commonly used to logically divide the contents of the region. |} * 4) fascia and muscles of [[pelvic floor]] ([[levator ani]], [[coccygeus]]) ===Areas of the perineum=== The region of the perineum can be considered a distinct area from pelvic cavity, with the two regions separated by the [[pelvic diaphragm]]. The following areas are thus classified as parts of the perineal region: * perineal pouches: superficial and deep (see above for details) * [[Ischioanal fossa]] - a fat filled space at the lateral sides of anal canal. It is bounded laterally by obturator internus muscle, medially by pelvic diaphragm and anal canal. Its base is the skin. ** [[Anal canal]] ** [[Pudendal canal]] - contains [[internal pudendal artery]] and the [[pudendal nerve]]. ==Additional images== <gallery> Image:Gray239.png|Diameters of inferior aperture of lesser pelvis (female). Image:Gray405.png|The perineum. The integument and superficial layer of superficial fascia reflected. Image:Gray408.png|Muscles of the female perineum. Image:Gray542.png|The superficial branches of the internal pudendal artery. Image:Gray1077.png|The posterior aspect of the rectum exposed by removing the lower part of the sacrum and the coccyx. Image:Gray1119.png|Stages in the development of the external sexual organs in the male and female. </gallery> == References == <references/> ==See also== *[[Pelvic floor]] *[[Deep perineal pouch]] ==External links== * {{NormanAnatomy|perineum}} {{Torso general}} [[Category:Perineum| ]] [[Category:Pelvis]] <!-- The below are interlanguage links. --> [[ar:عجان]] [[bg:Перинеум]] [[cs:Hráz (anatomie)]] [[da:Mellemkød]] [[de:Perineum]] [[et:Lahkliha]] [[el:Περίνεο]] [[es:Periné]] [[fa:میاندوراه]] [[fr:Périnée]] [[ko:회음부]] [[it:Perineo]] [[la:Perineum]] [[lt:Tarpvietė]] [[nl:Perineum]] [[ja:会陰]] [[nds:Damm (Anatomie)]] [[pl:Krocze]] [[pt:Períneo]] [[ro:Perineu]] [[ru:Промежность]] [[fi:Väliliha]] [[sv:Mellangård]] [[vi:Hội âm]] [[uk:Промежина]] [[zh:會陰]]