Middle pharyngeal constrictor muscle

{{Short description|Muscle in the neck}} {{Infobox muscle | Name = Middle pharyngeal constrictor muscle | Latin = musculus constrictor pharyngis medius | Image = Musculusconstrictorpharyngismedius.png | Caption = Muscles of the [[human pharynx|pharynx]] and [[cheek]] (middle pharyngeal constrictor muscle labeled as ''constrictor pharyngis medius'' at center left) | Image2 = Gray1031.png | Caption2 = Muscles of the pharynx, viewed from behind, together with the associated vessels and nerves (middle pharyngeal constrictor muscle labeled as ''Mid. constr.'' at center) | Origin = [[Hyoid bone]] | Insertion = [[Pharyngeal raphe]] | Blood = [[Ascending pharyngeal artery]] | Nerve = [[Pharyngeal plexus|Pharyngeal plexus of vagus nerve]] | Action = [[Swallowing]] }} The '''middle pharyngeal constrictor''' is a fan-shaped [[muscle]] located in the [[neck]]. It is one of three [[pharyngeal constrictor|pharyngeal constrictor muscle]]s. 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 (digestion)|bolus]] downwards along the pharynx towards the esophagus, facilitating swallowing.

==Structure== The middle pharyngeal constrictor is a sheet-like, fan-shaped muscle.<ref name=":2242">{{Cite book |last=Standring |first=Susan |title=Gray's Anatomy: The Anatomical Basis of Clinical Practice |year=2020 |isbn=978-0-7020-7707-4 |edition=42th |location=New York |pages=712–713 |oclc=1201341621}}</ref>

The muscle's fibers diverge from their origin: the more inferior fibres descend deep to the [[constrictor inferior|inferior pharyngeal constrictor muscle]]; the middle portion of fibres pass transversely; the more superior fibers ascend and overlap the [[constrictor superior|superior pharyngeal constrictor muscle]].<ref name=":2242" />

=== 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]].<ref name=":2242" /> * '''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.<ref name=":2242" />

=== Insertion === The muscle inserts (posteriorly) into the [[pharyngeal raphe]],<ref name=":2242" /> blending with its contralateral partner at the midline.{{Citation needed|date=July 2023}}

=== Innervation === Similarly to the [[Superior pharyngeal constrictor muscle|superior]] and [[inferior pharyngeal constrictor muscle]]s, it is innervated by a branch of the [[vagus nerve]] through the [[pharyngeal plexus]].{{Citation needed|date=July 2023}}

=== Actions/movements === The contraction of the muscle constricts the middle portion of the [[pharynx]].<ref name=":2242" />

==Function== The muscle contracts during swallowing:<ref name=":2242" /> as soon as the [[Bolus (digestion)|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]].<ref name="pmid6435057">{{cite journal |vauthors=Rowe LD, Miller AJ, Chierici G, Clendenning D |title=Adaptation in the function of pharyngeal constrictor muscles |journal=[[Otolaryngology–Head and Neck Surgery]] |volume=92 |issue=4 |pages=392–401 |date=August 1984 |doi=10.1177/019459988409200404 |pmid=6435057 |s2cid=32361287 }}</ref><ref name="DonnerBosnia1985">{{cite journal|last1=Donner|first1=Martin W.|last2=Bosnia|first2=James F.|last3=Robertson|first3=Diane L.|title=Anatomy and physiology of the pharynx|journal=Gastrointestinal Radiology|volume=10|issue=1|year=1985|pages=197–212|issn=0364-2356|doi=10.1007/BF01893103|pmid=4029536|s2cid=37515662}}</ref>

They also have respiratory mechanical effects.<ref name="Kuna2000">{{cite journal|last1=Kuna|first1=Samuel T|title=Respiratory-related activation and mechanical effects of the pharyngeal constrictor muscles|journal=Respiration Physiology|volume=119|issue=2–3|year=2000|pages=155–161|issn=0034-5687|doi=10.1016/S0034-5687(99)00110-3|pmid=10722858}}</ref>

==Additional images== <gallery> Image:Gray186.png|Hyoid bone. Anterior surface. Enlarged. Image:Gray385.png|Muscles of the neck. Lateral view. Image:Slide12mmm.JPG|Middle pharyngeal constrictor muscle Image:Slide4iiii.JPG|Middle pharyngeal constrictor muscle Image:Slide1kuku.JPG|Deep dissection of larynx, pharynx and tongue seen from behind Image:Slide2kuku.JPG|Deep dissection of larynx, pharynx and tongue seen from behind Image:Slide3kuku.JPG|Deep dissection of larynx, pharynx and tongue seen from behind </gallery>

==References== {{Gray's}} {{Reflist}}

==Further reading== *Its role in speech: {{cite journal|last1=Hamaker|first1=Ronald C.|last2=Blom|first2=Eric D.|title=Botulinum Neurotoxin for Pharyngeal Constrictor Muscle Spasm in Tracheoesophageal Voice Restoration|journal=The Laryngoscope|volume=113|issue=9|year=2003|pages=1479–1482|issn=0023-852X|doi=10.1097/00005537-200309000-00010|pmid=12972919|s2cid=12251825}} *Its role in Hyoid bone syndrome: {{cite journal|last1=Ernest|first1=Edwin A.|last2=Salter|first2=E. George|title=Hyoid bone syndrome: A degenerative injury of the middle pharyngeal constrictor muscle with photomicroscopic evidence of insertion tendinosis|journal=The Journal of Prosthetic Dentistry|volume=66|issue=1|year=1991|pages=78–83|issn=0022-3913|doi=10.1016/0022-3913(91)90357-3|pmid=1941681}}

==External links== * {{NormanAnatomy|lesson8}} ({{NormanAnatomyFig|latpharyngealitems3}})

[[Category:Muscles of the head and neck]] [[Category:Pharynx]]