- Cricoid
Infobox Anatomy
Name = PAGENAME
Latin = cartilago cricoidea
GraySubject = 236
GrayPage = 1074
Caption = Anterolateral view of head and neck. (Cricoid cartilage labeled at center left.)
Caption2 = The ligaments of the larynx. Antero-lateral view. (Cricoid cartilage visible near bottom center.)
Precursor = 4th and 6thbranchial arch
System =
Artery =
Vein =
Nerve =
Lymph =
MeshName = Cricoid+Cartilage
MeshNumber = A02.165.507.211
DorlandsPre =
DorlandsSuf =
The cricoid cartilage, or simply cricoid (from the Greek "krikoeides" meaning "ring-shaped"), is the only complete ring ofcartilage around the trachea.Location
It sits just inferior to the
thyroid cartilage in theneck , and is joined to it medially by the mediancricothyroid ligament and postero-laterally by the cricothyroid joints.Inferior to it are the rings of cartilage around the trachea (which are not continuous - rather they are C-shaped with a gap posteriorly). The cricoid is joined to the first tracheal ring by thecricotracheal ligament , and this can be felt as a more yielding area between the firm thyroid cartilage and firmer cricoid.It is also anatomically related to the
thyroid gland; although the thyroidisthmus is inferior to it, the two lobes of the thyroid extend superiorly on each side of the cricoid as far as the thyroid cartilage above it.The posterior part of the cricoid is slightly broader than the anterior and lateral parts, and is called the lamina, while the
anterior part is the band; this may be the reason for the common comparison made between the cricoid and asignet ring .Function
The function of the cricoid is to provide attachments for the various
muscle s, cartilages, andligament s involved in opening and closing the airway and in speech production.Composition
It is made of
hyaline cartilage , and so can become calcified or even ossified, particularly in old age.Clinical significance
When
intubating a patient undergeneral anesthesia prior to surgery, theanesthesiologist will press on the cricoid cartilage to compress the esophagus behind it so as to preventgastric reflux from occurring.Gastric reflux could cause
aspiration if this is not done considering the general anesthesia can cause relaxation of thegastro-esophageal sphincter allowing stomach contents to ascend through the esophagus into the trachea.
=AdditionalSee also
*
Post-cricoid carcinoma
*Tracheotomy External links
* [http://www.nda.ox.ac.uk/wfsa/html/u02/u02_b03.htm Illustration at nda.ox.ac.uk]
* - "Skeleton of the larynx."
* (NormanAnatomyFig|larynxsagsect)
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