Palatopharyngeus muscle

At a glance

English

Palatopharyngeus muscle

Latin (TA2)

Musculus palatopharyngeus

System

Muscle

Region

Whole body

Side

Paired, left and right

About the palatopharyngeus muscle

Palatopharyngeus is a slender muscle of the soft palate and pharynx. Covered by mucous membrane, it raises the palatopharyngeal arch, the rear of the two folds visible at each side of the back of the mouth. In front of it, the palatoglossal arch contains palatoglossus, and the palatine tonsil sits in the hollow between the two arches. The muscle is broad at its ends and narrow in the middle.

It begins in the soft palate in two layers that are separated by levator veli palatini. The thicker anterior layer arises from the palatine aponeurosis and the back edge of the hard palate. The thinner posterior layer lies against the mucosa on the upper surface of the palate and meets its partner in the midline. The two layers join at the side of the palate and the muscle descends behind the tonsil, inside the constrictors. It blends with stylopharyngeus and inserts with it into the back of the thyroid cartilage, while other fibres spread into the side wall of the pharynx or cross the midline behind to meet the opposite muscle.

When swallowing, the muscle raises the pharynx and larynx and shortens the pharynx. At the same time the two palatopharyngeal folds draw towards each other, while levator veli palatini lifts and tensor veli palatini tightens the palate. The uvula fills the small gap left between the folds, closing off the nasal part of the pharynx so that food cannot pass up into the nose. The folds then act as a sloping chute that guides the bolus down into the lower pharynx.

Its motor supply comes through the pharyngeal plexus from the vagus nerve, with blood from the ascending palatine and ascending pharyngeal arteries and the greater palatine artery. Some upper fibres form a ridge on the back wall of the nasopharynx, the palatopharyngeal sphincter or Passavant ridge, which helps seal the nasal airway in speech. In surgery for snoring and sleep apnoea, the muscle is often repositioned to widen the airway.

Attachments, action and supply

Origin

Palatine aponeurosis and the posterior border of the hard palate, in two layers within the soft palate.

Insertion

Back edge of the thyroid cartilage, with stylopharyngeus, and the side and back wall of the pharynx.

Action

Elevates the pharynx and larynx, draws the palatopharyngeal folds together to close the nasopharynx in swallowing.

Nerve supply

Pharyngeal plexus (vagus nerve).

Blood supply

Ascending palatine, ascending pharyngeal and greater palatine arteries.