Middle pharyngeal constrictor muscle
Template:Short description Script error: No such module "Infobox".Template:Template otherTemplate:Main otherScript error: No such module "Check for unknown parameters". The middle pharyngeal constrictor is a fan-shaped muscle located in the neck. It is one of three pharyngeal constrictor muscles. It is smaller than the inferior pharyngeal constrictor muscle.
The middle pharyngeal constrictor originates from the greater cornu and lesser cornu of the hyoid bone, and the stylohyoid ligament. It inserts onto the pharyngeal raphe. It is innervated by a branch of the vagus nerve through the pharyngeal plexus. It acts to propel a bolus downwards along the pharynx towards the esophagus, facilitating swallowing.
Structure
The middle pharyngeal constrictor is a sheet-like, fan-shaped muscle.[1]
The muscle's fibers diverge from their origin: the more inferior fibres descend deep to the inferior pharyngeal constrictor muscle; the middle portion of fibres pass transversely; the more superior fibers ascend and overlap the superior pharyngeal constrictor muscle.[1]
Origin
Two parts of the middle pharyngeal constrictor muscle are distinguished according to its sites of origin:
- Ceratopharyngeal part - arises (the entire superior margin of) the greater cornu of the hyoid bone.[1]
- Chondropharyngeal part - arises from the lesser cornu of the hyoid bone, and (the inferior portion of) the stylohyoid ligament. The chondropharyngeal part represents the muscle's anterior origin.[1]
Insertion
The muscle inserts (posteriorly) into the pharyngeal raphe,[1] blending with its contralateral partner at the midline.Script error: No such module "Unsubst".
Innervation
Similarly to the superior and inferior pharyngeal constrictor muscles, it is innervated by a branch of the vagus nerve through the pharyngeal plexus.Script error: No such module "Unsubst".
Actions/movements
The contraction of the muscle constricts the middle portion of the pharynx.[1]
Function
The muscle contracts during swallowing:[1] as soon as the bolus of food is received in the pharynx, the elevator muscles relax, the pharynx descends, and the constrictors contract upon the bolus, and convey it downward towards the esophagus.[2][3]
They also have respiratory mechanical effects.[4]
Additional images
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Hyoid bone. Anterior surface. Enlarged.
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Muscles of the neck. Lateral view.
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Middle pharyngeal constrictor muscle
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Middle pharyngeal constrictor muscle
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Deep dissection of larynx, pharynx and tongue seen from behind
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Deep dissection of larynx, pharynx and tongue seen from behind
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Deep dissection of larynx, pharynx and tongue seen from behind
References
Public domain This article incorporates text in the public domain from Template:Wikidatathe 20th edition of Gray's Anatomy (1918) Template:Main other Template:Reflist
Further reading
- Its role in speech: Script error: No such module "Citation/CS1".
- Its role in Hyoid bone syndrome: Script error: No such module "Citation/CS1".
External links
- lesson8 at The Anatomy Lesson by Wesley Norman (Georgetown University) (Template:NormanAnatomyFig)
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