Cricopharyngeal part of inferior pharyngeal constrictor
Pars cricopharyngea constrictoris inferioris pharyngis
- Latin synonym: Musculus cricopharyngeus; ; Pars circopharyngica
- Synonym: Cricopharyngeus muscle
- Related terms: Cricopharyngeal part; Cricopharyngeus
Definition
The cricopharyngeal part of inferior pharyngeal constrictor arises from the lateral surface of the cricoid cartilage and encircles the upper end of the esophagus as a horizontal muscular band. Its fibers do not join the median pharyngeal raphe but blend directly with the circular fibers of the esophagus, forming the upper esophageal sphincter (cricopharyngeal sphincter).
The cricopharyngeal part is supplied by the recurrent laryngeal and external laryngeal nerves.
Functionally, it remains tonically contracted between swallows to prevent air from entering the esophagus and to stop reflux of esophageal contents into the pharynx, relaxing transiently during swallowing to allow the food bolus to pass into the esophagus.
References
Gray, H. (2016) Gray’s Anatomy: The Anatomical Basis of Clinical Practice. 41st edn. Edited by S. Standring. New York: Elsevier. Chapter 34: Pharynx, pp. 581-582.
