![]() Venous drainage of the tongue is via deep lingual veins and a single dorsal lingual vein these vessels drain into the sublingual vein, which in turn empties directly into the internal jugular vein. Dorsal lingual arteries supply the base of the tongue, whereas deep lingual arteries supply the body of the tongue. After this, the lingual artery travels between the hyoglossus (superficial) and middle pharyngeal constrictor (deep) to supply blood to the tongue. The lingual artery is a direct branch of the external carotid artery it takes off from the external carotid at the level of the greater horn of the hyoid bone. The styloglossus muscle receives its blood supply from the sublingual branch of the lingual artery. Following mastication, these movements promote passage of the food bolus towards the oropharynx. The styloglossus muscle functions to retract and elevate the tongue in a posterior and superior fashion. These smaller bundles course between the inferior longitudinal intrinsic muscles of the tongue and the genioglossus muscle and ultimately insert into the lingual septum. The posterior bundles of the styloglossus muscle split into approximately 10 smaller bundles of fibers that enter the tongue. Anteriorly, the bundles run bilaterally and meet at the midline of the floor of the tongue, forming an arch. The fibers of the styloglossus muscle can be divided into anterior and posterior bundles. External and internal fibers of the styloglossus muscle also fuse with parts of the superior pharyngeal constrictor muscle and the palatoglossus muscle, respectively, with three bundles traveling anteriorly towards the apex of the tongue and an inferior longitudinal bundle joining the inferior fibers of the genioglossus muscle. Function Īs soon as the bolus of food is received in the pharynx, the elevator muscles relax, the pharynx descends, and the constrictors contract upon the bolus, conveying it downward into the esophagus.Originating at the apex of the styloid process of the temporal bone, the styloglossus muscle inserts into the lateral aspect of the tongue, namely into the fibers of the intrinsic longitudinal muscles and between the two parts of the hyoglossus muscle. Actions/movements Ĭonstriction of the muscle constricts the superior portion of the pharynx. The superior fibers arch beneath the levator veli palatini muscle and the Eustachian tube. There is an interval between superior pharyngeal constrictor and middle pharyngeal constrictor, this space contains glossopharyngeal nerve, lingual nerve and the stylopharyngeus muscle. The interval between the upper border of the muscle and the base of the skull is closed by the pharyngeal aponeurosis, and is known as the sinus of Morgagni. Vasculature Īrterial supply is provided primarily by the pharyngeal branch of the ascending pharyngeal artery, and the tonsilar branch of the facial artery. The superior pharyngeal constrictor muscle receives motor innervation from the pharyngeal plexus of vagus nerve. The muscle's fibres extend posterior-ward from its origin to form the midline pharyngeal raphe which then attaches onto the pharyngeal tubercle (of the basilar part of the occipital bone). Glossopharyngeal part - a few fibers originating from the side of the tongue.Mylopharyngeal part - originating from the alveolar process of the mandible above the posterior end of the mylohyoid line.Buccopharyngeal part - originating from the pterygomandibular raphe.Pterygopharyngeal part - originating from the lower third of the posterior margin of the medial pterygoid plate and its hamulus.įour parts of the muscle are distinguished according to the origin: The sites of origin of the muscles collectively are the pterygoid hamulus (and occasionally the adjoining posterior margin of the medial pterygoid plate) anteriorly, (the posterior margin of) the pterygomandibular raphe, the posterior extremity of the mylohyoid line of mandible, and (negligibly) the side of the tongue. It is thinner than the middle and inferior constrictor muscles. The superior constrictor muscle is a quadrilateral, sheet-like muscle. It acts to convey a bolus down towards the esophagus, facilitating swallowing. It is innervated by pharyngeal branch of the vagus nerve via the pharyngeal plexus. The muscle inserts onto the pharyngeal raphe, and pharyngeal spine. ![]() The muscle is divided into four parts according to its four distincts origins: a pterygopharyngeal, buccopharyngeal, mylopharyngeal, and a glossopharyngeal part. It is the uppermost and thinnest of the three pharyngeal constrictors. The superior pharyngeal constrictor muscle is a quadrilateral muscle of the pharynx. ![]()
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