![]() ![]() The superior pharyngeal constrictor muscle is innervated by the pharyngeal branch of the vagus nerve via the pharyngeal plexus. ActionĪs 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, and convey it downward into the esophagus. 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. Some of the fibers of these muscles terminate by blending with the superior constrictor muscle. This muscle has its origin in the stylohyoid ligament with Greater and Lesser horns of the hyoid bone. The superior fibers arch beneath the levator veli palatini muscle and the Eustachian tube. Middle pharyngeal constrictor This muscle lies below the level of the superior pharyngeal constrictor muscle. Middle pharyngeal constrictor: origin from the hyoid bone and stylohyoid ligament. The fibers curve backward to be inserted into the median raphe, being also prolonged by means of an aponeurosis to the pharyngeal spine on the basilar part of the occipital bone. 6.Middle pharyngeal constrictor 7.Inferior pharyngeal constrictor 8.Cricopharyngeus (inferior part of inferior pharyngeal constrictor) Superior pharyngeal constrictor: origin from the mandible, medial pterygoid plate, and the pterygomandibular raphe. ![]() and by a few fibers from the side of the tongue ( Glossopharyngeal part) from the alveolar process of the mandible above the posterior end of the mylohyoid line ( Mylopharyngeal part) from the pterygomandibular raphe ( Buccopharyngeal part) the lower third of the posterior margin of the medial pterygoid plate and its hamulus ( Pterygopharyngeal part) The four parts of this muscle arise from: Action: Constricts the wall of the pharynx during swallowing to propel the food bolus downwards. It inserts posteriorly onto the pharyngeal raphe. The muscle is divided into four parts: A pterygopharyngeal, buccopharyngeal, mylopharyngeal and a glossopharyngeal part. Attachments: Originates from the stylohyoid ligament and the hyoid bone. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |