Salpingopharyngeus muscle


The salpingopharyngeus muscle is a muscle of the pharynx. It arises from the lower part of the cartilage of the Eustachian tube, and inserts into the palatopharyngeus muscle by blending with its posterior fasciculus. It is innervated by vagus nerve (cranial nerve X) via the pharyngeal plexus. It raises the pharynx and larynx during deglutition and laterally draws the pharyngeal walls up. It opens the pharyngeal orifice of the Eustachian tube during swallowing to allow for the equalization of pressure between it and the pharynx.

Structure

The salpingopharyngeus is a very slender muscle. It passes inferior-ward from its origin to its insertion within the salpingopharyngeal fold.

Origin

The salpingopharyngeus muscle arises from the inferior portion of the cartilaginous part of the pharyngotympanic tube near its pharyngeal opening. Its origin creates the posterior welt of the torus tubarius.

Insertion

It ends distally by blending with the palatopharyngeus muscle.

Innervation

The salpingopharyngeus receives motor innervation from the pharyngeal plexus of the vagus nerve.

Blood supply

The salpingopharyngeus muscle receives arterial supply from the ascending palatine artery, greater palatine artery, and the pharyngeal branch of the ascending pharyngeal artery.

Variation

The salpingopharyngeus muscle is absent in about 40% of individuals. It is more common in thin individuals.

Function

The salpingopharyngeus muscle raises the pharynx and larynx during deglutition and laterally draws the pharyngeal walls up. Unusually, it is relaxed during deglutition, but contracts at all other times. It opens the pharyngeal orifice of the Eustachian tube during swallowing allowing for the equalization of pressure between it and the pharynx.