Soft palate

At a glance

English

Soft palate

Latin (TA2)

Palatum molle

System

Digestive

Region

Whole body

Side

Single, on the midline

About the soft palate

The soft palate, or velum, continues backwards from the edge of the hard palate. It contains no bone; its framework is a tough fibrous sheet, the palatine aponeurosis, to which its muscles attach. At rest it slopes down and back like a curtain, its upper surface facing the nasopharynx and its lower surface facing the mouth. The free back edge carries the uvula in the midline.

From each side two arches run down from the palate: the palatoglossal arch in front, to the side of the tongue, and the palatopharyngeal arch behind, to the wall of the pharynx. Between them lies the tonsillar fossa holding the palatine tonsil. Together with the back of the tongue, the front arches bound the opening from the mouth into the oropharynx, the oropharyngeal isthmus (isthmus of the fauces).

Five paired muscles act on it. The tensor veli palatini tightens the aponeurosis, its tendon turning around the hamulus of the medial pterygoid plate; it also opens the auditory tube during swallowing and yawning. The levator veli palatini raises the palate. The palatoglossus and palatopharyngeus pull the palate down towards the tongue and pharynx and narrow the arches, and the musculus uvulae shortens and thickens the uvula. In swallowing, the palate rises and tightens against a ridge on the back wall of the pharynx, sealing the nasopharynx so food and drink cannot pass up into the nose. The same seal is used in speech to stop air escaping through the nose for most consonants.

The mucous membrane contains many small mucous glands and some taste buds. A cleft palate, failure of the two halves to fuse, leaves an opening that lets food enter the nose and makes speech sound nasal. After a stroke or vagus nerve injury the palate on the weak side fails to rise, and the uvula is pulled towards the healthy side. A floppy palate vibrating in the airstream is a main cause of snoring.

Function and supply

Function

Closes off the nasopharynx during swallowing and most speech, and with the tongue controls passage from mouth to pharynx.

Nerve supply

Motor: pharyngeal plexus (vagus) for all its muscles except tensor veli palatini (mandibular nerve). Sensory: lesser palatine nerves from the maxillary nerve, with glossopharyngeal fibres behind.

Blood supply

The lesser palatine branches of the descending palatine artery, the ascending palatine branch of the facial artery and palatine branches of the ascending pharyngeal artery.