Middle pharyngeal constrictor muscle

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.

Middle pharyngeal constrictor muscle
Muscles of the pharynx and cheek (middle pharyngeal constrictor muscle labeled as constrictor pharyngis medius at center left)
Muscles of the pharynx, viewed from behind, together with the associated vessels and nerves (middle pharyngeal constrictor muscle labeled as Mid. constr. at center)
Details
OriginHyoid bone
InsertionPharyngeal raphe
ArteryAscending pharyngeal artery
NervePharyngeal plexus of vagus nerve
ActionsSwallowing
Identifiers
LatinMusculus constrictor pharyngis medius
TA98A05.3.01.108
TA22184
FMA46622
Anatomical terms of 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:

Insertion

The muscle inserts (posteriorly) into the pharyngeal raphe,[1] blending with its contralateral partner at the midline.

Innervation

Similarly to the superior and inferior pharyngeal constrictor muscles, it is innervated by a branch of the vagus nerve through the pharyngeal plexus.

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
  • Hyoid bone. Anterior surface. Enlarged.
    Hyoid bone. Anterior surface. Enlarged.
  • Muscles of the neck. Lateral view.
    Muscles of the neck. Lateral view.
  • Middle pharyngeal constrictor muscle
    Middle pharyngeal constrictor muscle
  • Middle pharyngeal constrictor muscle
    Middle pharyngeal constrictor muscle
  • Deep dissection of larynx, pharynx and tongue seen from behind
    Deep dissection of larynx, pharynx and tongue seen from behind
  • Deep dissection of larynx, pharynx and tongue seen from behind
    Deep dissection of larynx, pharynx and tongue seen from behind
  • Deep dissection of larynx, pharynx and tongue seen from behind
    Deep dissection of larynx, pharynx and tongue seen from behind

References

Public domain This article incorporates text in the public domain from page 1143 of the 20th edition of Gray's Anatomy (1918)

  1. Standring, Susan (2020). Gray's Anatomy: The Anatomical Basis of Clinical Practice (42th ed.). New York. pp. 712–713. ISBN 978-0-7020-7707-4. OCLC 1201341621.{{cite book}}: CS1 maint: location missing publisher (link)
  2. Rowe LD, Miller AJ, Chierici G, Clendenning D (August 1984). "Adaptation in the function of pharyngeal constrictor muscles". Otolaryngology–Head and Neck Surgery. 92 (4): 392–401. doi:10.1177/019459988409200404. PMID 6435057. S2CID 32361287.
  3. Donner, Martin W.; Bosnia, James F.; Robertson, Diane L. (1985). "Anatomy and physiology of the pharynx". Gastrointestinal Radiology. 10 (1): 197–212. doi:10.1007/BF01893103. ISSN 0364-2356. PMID 4029536. S2CID 37515662.
  4. Kuna, Samuel T (2000). "Respiratory-related activation and mechanical effects of the pharyngeal constrictor muscles". Respiration Physiology. 119 (2–3): 155–161. doi:10.1016/S0034-5687(99)00110-3. ISSN 0034-5687. PMID 10722858.

Further reading
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