laryngopharygeus (upper esophageal sphincter, cricopharyngeus)

Inferior constrictor muscle of pharynx; lowest part of outer circular muscle layer of pharynx. Origin: 1) outer surfaces of thyroid cartilage & cricoid cartilage Insertion: pharyngeal raphe in the posterior wall of the pharynx Action: 1) narrows lower part of the pharynx in swallowing 2) cricopharyngeus has a sphincter component for esophagus, allowing some voluntary control of eructation & reflux Innervation: pharyngeal plexus Pathology: - retrograde cricopharyngeus dysfunction

References

Stedman's Medical Dictionary 27th ed, Williams & Wilkins, Baltimore, 1999