innervations inferior pharyngeal constrictor

The inner longitudinal layer consists of the palatopharyngeus, salpingopharyngeus, and stylopharyngeus muscles. These constrictor muscles work together and contract to push food after swallowing to propel it from the oral cavity into the esophagus. When the inferior constrictors contract, they constrict the lower portion of the pharynx. The cricopharyngeus muscle originates from the cricoid cartilage and blends into the esophageal muscle. The thyropharyngeus muscle originates from the thyroid cartilage and inserts into the median pharyngeal raphe. The inferior pharyngeal constrictor muscle further divides into two muscles, the thyropharyngeus, and the cricopharyngeus muscle. The middle constrictor muscle contracts to constrict the middle portion of the pharynx. The middle constrictor inserts into the median pharyngeal raphe as well as blending in with fibers of the superior and inferior constrictors. The middle constrictor muscle originates from the greater and lesser horn of the hyoid bone and stylohyoid ligament. When the superior constrictor muscle contracts, it constricts the upper portion of the pharynx. The pharyngeal raphe is a midline tendinous seam where the constrictor muscles meet. This superior constrictor muscle inserts into the base of the skull at the pharyngeal tubercle and the pharyngeal raphe. The superior constrictor muscle originates from the pterygoid process, posterior end of the mylohyoid line of mandible, and the pterygomandibular ligament/raphe. The outer circular layer consists of the superior, middle, and inferior constrictor muscles. The sensory fibers of the pharyngeal muscles come from the vagus, glossopharyngeal, and the maxillary division of the trigeminal nerve. The vagus nerve and its branches provide motor innervation to all other muscles of the pharynx. The glossopharyngeal nerve provides motor to the stylopharyngeus muscle. The motor branch of the pharyngeal plexus comes from the vagus and glossopharyngeal nerve. The motor and sensory innervation of pharyngeal muscles is provided primarily by the pharyngeal plexus. Lymphatic drainage of the pharynx first goes to the retropharyngeal lymph node then into the deep cervical lymph node. Venous drainage of the pharynx is into the pharyngeal venous plexus that eventually drains into the internal jugular vein. The branches of the external carotid artery include the ascending pharyngeal, facial, lingual, and maxillary artery. Blood Supply and LymphaticsĪrterial supply to the pharyngeal muscle is from branches of the external carotid artery. Subsequently, the vagus nerve innervates most of the pharyngeal constrictor muscles. The fourth branchial arch forms most of the pharyngeal constrictors as well as the superior laryngeal branch of the vagus nerve (CN X). The third arch also forms the glossopharyngeal nerve (CN IX), which is the nerve that innervates the stylopharyngeus muscle. The third branchial arch develops into the stylopharyngeus muscle. The muscles and nerve innervation of the pharynx derive embryologically from the third and fourth brachial arches. These muscles work together to help move food bolus from the oral cavity into the esophagus. The palatopharyngeus, salpingopharyngeus, and stylopharyngeus muscles are the inner longitudinal muscles that contract to raise the pharynx and larynx. The superior pharyngeal constrictor contract to narrow its lumen to assist with bolus transport as well as seal the nasopharynx to prevent food from going up - the middle and inferior pharyngeal constrictors contract to narrow its lumen to assist with bolus transport. These constrictor muscles originate from bones and cartilage anteriorly and insert posteriorly to a tendinous seam called the pharyngeal raphe. The outer circular layer consists of the superior, middle, and inferior pharyngeal constrictor muscles. The pharynx extends from the posterior nasal and oral cavity to the cricoid cartilage before blending into the esophagus. The inner longitudinal layer consists of the palatopharyngeus, salpingopharyngeus, and stylopharyngeus muscles. The pharyngeal muscles receive innervation from the vagus and glossopharyngeal nerve to work in sync to propel food from the oral cavity into the esophagus. A group of muscles called the pharyngeal muscles, which consist of the outer circular layer and the inner longitudinal layer, forms the lumen of the pharynx. The pharynx is the digestive system posterior to the nasal cavity, oral cavity, and larynx and divides into the oropharynx, nasopharynx, and laryngopharynx.

Innervations inferior pharyngeal constrictor