Stylopharyngeus muscle
Encyclopedia
The stylopharyngeus is a muscle in the head that stretches between the styloid process
and the pharynx
.
, passes downward along the side of the pharynx
between the superior pharyngeal constrictor and the middle pharyngeal constrictor, and spreads out beneath the mucous membrane.
Some of its fibers are lost in the constrictor muscles, while others, joining with the palatopharyngeus muscle, are inserted into the posterior border of the thyroid cartilage
.
The glossopharyngeal nerve
runs on the lateral side of this muscle, and crosses over it to reach the tongue.
(CN IX) and is done by its motor branch which supplies special visceral efferent
(SVE) fibers to it.
Styloid process
In anatomy, a styloid process , usually serving as points of attachment for muscles, refers to the slender, pointed process of :* temporal bone of the skull - Temporal styloid process...
and the pharynx
Pharynx
The human pharynx is the part of the throat situated immediately posterior to the mouth and nasal cavity, and anterior to the esophagus and larynx. The human pharynx is conventionally divided into three sections: the nasopharynx , the oropharynx , and the laryngopharynx...
.
Structure
The stylopharyngeus is a long, slender muscle, cylindrical above, flattened below. It arises from the medial side of the base of the styloid processStyloid process
In anatomy, a styloid process , usually serving as points of attachment for muscles, refers to the slender, pointed process of :* temporal bone of the skull - Temporal styloid process...
, passes downward along the side of the pharynx
Pharynx
The human pharynx is the part of the throat situated immediately posterior to the mouth and nasal cavity, and anterior to the esophagus and larynx. The human pharynx is conventionally divided into three sections: the nasopharynx , the oropharynx , and the laryngopharynx...
between the superior pharyngeal constrictor and the middle pharyngeal constrictor, and spreads out beneath the mucous membrane.
Some of its fibers are lost in the constrictor muscles, while others, joining with the palatopharyngeus muscle, are inserted into the posterior border of the thyroid cartilage
Thyroid cartilage
The thyroid cartilage is the largest of the nine cartilages that make up the laryngeal skeleton, the cartilage structure in and around the trachea that contains the larynx....
.
The glossopharyngeal nerve
Glossopharyngeal nerve
The glossopharyngeal nerve is the ninth of twelve pairs of cranial nerves . It exits the brainstem out from the sides of the upper medulla, just rostral to the vagus nerve...
runs on the lateral side of this muscle, and crosses over it to reach the tongue.
Innervation
This is the only muscle in the pharynx innervated by the glossopharyngeal nerveGlossopharyngeal nerve
The glossopharyngeal nerve is the ninth of twelve pairs of cranial nerves . It exits the brainstem out from the sides of the upper medulla, just rostral to the vagus nerve...
(CN IX) and is done by its motor branch which supplies special visceral efferent
Special visceral efferent
Special visceral efferent refers to efferent nerves which supply muscles which derived from the branchial arches.Some sources prefer the term "branchiomotor", or "branchial efferent"....
(SVE) fibers to it.
Actions
The stylopharyngeus:- elevates the larynxLarynxThe larynx , commonly called the voice box, is an organ in the neck of amphibians, reptiles and mammals involved in breathing, sound production, and protecting the trachea against food aspiration. It manipulates pitch and volume...
- elevates the pharynxPharynxThe human pharynx is the part of the throat situated immediately posterior to the mouth and nasal cavity, and anterior to the esophagus and larynx. The human pharynx is conventionally divided into three sections: the nasopharynx , the oropharynx , and the laryngopharynx...
- dilates the pharynx to permit the passage of a large food bolus, thereby facilitating swallowing