Inguinal canal
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195083198
2008-03-01T08:42:51Z
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{{Infobox Anatomy |
Name = inguinal canal |
Latin = canalis inguinalis |
GraySubject = 258 |
GrayPage = 1239 |
Image = Gray1227.png |
Caption = Front of abdomen, showing surface markings for arteries and inguinal canal. (Inguinal canal is tube at lower left.) |
Image2 = Gray1143.png |
Caption2 = The [[scrotum]]. On the left side the cavity of the [[tunica vaginalis]] has been opened; on the right side only the layers superficial to the [[Cremaster]] have been removed. (Right [[inguinal canal]] visible at upper left.) |
System = |
MeshName = Inguinal+Canal |
MeshNumber = A01.047.412 |
}}
The '''inguinal canal''' is a passage in the anterior (toward the front of the body) abdominal wall which in men conveys the [[spermatic cord]] and in women the [[Round ligament of uterus|round ligament]]. The inguinal canal is larger and more prominent in men.
==Site==
The inguinal canal is situated just above the medial half of the inguinal ligament.
==Length==
Approximately 4cm (1.57 inches).
== Direction ==
It is oblique directed downwards, forwards and medially.
==Boundaries==
A first-order approximation is to visualize the canal as a cylinder, stretching from the [[deep inguinal ring]] to the [[superficial inguinal ring]].<ref name="titleGross Anatomy Image">{{cite web |url=http://anatomy.med.umich.edu/atlas/abdo_wall64.html |title=Gross Anatomy Image |accessdate=2007-11-20 |format= |work=}}</ref>
To help define the boundaries, the canal is often further approximated as a box with six sides. Not including the two rings, the remaining four sides are usually called the "anterior wall", "posterior wall", "roof", and "floor".<ref name="isbn0-443-06612-4">{{cite book |author=Adam Mitchell; Drake, Richard; Gray, Henry David; Wayne Vogl |title=Gray's anatomy for students |publisher=Elsevier/Churchill Livingstone |location= |year=2005 |pages=260 |isbn=0-443-06612-4 |oclc= |doi=}}</ref> These consist of the following:
{| class="wikitable"
| || '''superior wall (roof):'''<BR>[[internal oblique]]<BR>[[transversus abdominis]] ||
|-
| '''anterior wall:'''<BR>[[aponeurosis]] of [[external oblique]]<BR>aponeurosis of [[internal oblique]] (lateral third of canal only)<ref name="isbn0-7817-3639-0">{{cite book |author=Dalley, Arthur F.; Moore, Keith L. |title=Clinically oriented anatomy |publisher=Lippincott Williams & Wilkins |location=Hagerstwon, MD |year=2006 |pages=217 |isbn=0-7817-3639-0 |oclc= |doi=}}</ref><BR>[[superficial inguinal ring]] (medial third of canal only)<ref name="isbn0-7817-4255-2">{{cite book |author=Arthur F., II Dalley; Anne M. R. Agur |title=Grant's Atlas of Anatomy |publisher=Lippincott Williams & Wilkins |location=Hagerstwon, MD |year= |pages=102 |isbn=0-7817-4255-2 |oclc= |doi=}}</ref> || ''(inguinal canal)'' || '''posterior wall:'''<BR>[[transversalis fascia]]<BR>[[conjoint tendon]] (medial third of canal only)<ref name="isbn0-7817-4255-2">{{cite book |author=Arthur F., II Dalley; Anne M. R. Agur |title=Grant's Atlas of Anatomy |publisher=Lippincott Williams & Wilkins |location=Hagerstwon, MD |year= |pages=102 |isbn=0-7817-4255-2 |oclc= |doi=}}</ref><BR>[[deep inguinal ring]] (lateral third of canal only)<ref name="isbn0-7817-4255-2">{{cite book |author=Arthur F., II Dalley; Anne M. R. Agur |title=Grant's Atlas of Anatomy |publisher=Lippincott Williams & Wilkins |location=Hagerstwon, MD |year= |pages=102 |isbn=0-7817-4255-2 |oclc= |doi=}}</ref>
|-
| || '''inferior wall (floor):'''<BR>[[inguinal ligament]]<BR>[[lacunar ligament]] (medial third of canal only)<ref name="isbn0-7817-4255-2">{{cite book |author=Arthur F., II Dalley; Anne M. R. Agur |title=Grant's Atlas of Anatomy |publisher=Lippincott Williams & Wilkins |location=Hagerstwon, MD |year= |pages=102 |isbn=0-7817-4255-2 |oclc= |doi=}}</ref><BR>[[iliopubic tract]] (lateral third of canal only)<ref name="isbn0-7817-3639-0">{{cite book |author=Dalley, Arthur F.; Moore, Keith L. |title=Clinically oriented anatomy |publisher=Lippincott Williams & Wilkins |location=Hagerstwon, MD |year=2006 |pages=217 |isbn=0-7817-3639-0 |oclc= |doi=}}</ref> ||
|}
One way to remember these structures is with the mnemonic "MALT", starting at the top and going counterclockwise:
* M - '''m'''uscles
* A - '''a'''poneuroses
* L - '''l'''igaments
* T - '''t'''ransversalis/'''t'''endon
== Contents ==
* in males : the [[spermatic cord]]<ref name="titleAnatomy Tables - Inguinal Region">{{cite web |url=http://anatomy.med.umich.edu/gastrointestinal_system/inguinal_tables.html |title=Anatomy Tables - Inguinal Region |accessdate=2007-11-20 |format= |work=}}</ref> and its coverings + the [[ilioinguinal nerve]].
* in females : the [[round ligament of the uterus]] + the [[ilioinguinal nerve]].
The classic description of the contents of inguinal canal in the male are:
3 arteries: artery to vas, testicular artery, cremasteric artery
3 fascial layers: external spermatic, cremasteric, internal spermatic
3 other vessels: pampiniform plexus, vas deferens, lymphatics
1 nerve: gential branch of the genitofemoral nerve (L1/2)
The ilioinguinal nerve passes through the superficial ring to descend into the scrotum, but does not formally run through the canal.
==Development==
During development gonads (ovaries or testes) descend from their starting point on the posterior abdominal wall (para-aortically) and near the [[kidneys]] down the abdomen and through the inguinal canal to reach the [[scrotum]]. The testis then decends through the abdominal wall into the scrotum, behind the processus vaginalis (which later obliterates). Thus lymphatic spread from a testicular tumour is to the para-aortic nodes first, and not the inguinal nodes.
==Disorders==
Abdominal contents (potentially including intestine) can be abnormally displaced from the abdominal cavity. Where these contents exit through the inguinal canal the condition is known as an [[indirect inguinal hernia]]. This condition is far more common in men than in women, owing to the inguinal canal's small size in women.
A hernia that exits the abdominal cavity directly through the deep layers of the abdominal wall, thereby bypassing the inguinal canal, is known as a [[direct inguinal hernia]].
==Additional images==
<gallery>
Image:Gray1146.png|The spermatic cord in the inguinal canal.
Image:Inguinal fossae.PNG|Inguinal fossae
</gallery>
==See also==
* [[Superficial inguinal ring]]
* [[Deep inguinal ring]]
==References==
{{reflist}}
==External links==
* {{SUNYAnatomyLabs|36|01|01|02}}
* {{UMichAtlas|abdo_wall63}} - "The Male & Female Inguinal Canal"
* [http://www.nurseminerva.co.uk/images/hernia2a.jpg Diagram at nurseminerva.co.uk]
{{Torso general}}
[[Category:Abdomen]]
[[de:Leistenkanal]]
[[nl:Lieskanaal]]
[[pl:KanaĆ pachwinowy]]
[[pt:Canal inguinal]]