Dr. Manions Pharynx Notes:

The pharynx is a common passageway for both breathing and swallowing. The pharynx is divided into the nasopharynx, oropharynx, and laryngopharynx. The nasopharynx is the area just posterior to the nasal cavities and is superior to the soft palate. (Note: When one swallows or talks, the soft palate rises up and blocks the nasopharynx off from the rest of the pharynx. When breathing it is normally hanging). The oropharynx is inferior to the soft palate, superior to the epiglottis, and is posterior to the oral cavity. The laryngopharynx extends from the epiglottis to the base of the cricoid cartilage, and is posterior to the larynx. Contents of the nasopharynx: At the roof of the nasopharynx, one would find the pharyngeal tonsils (paired). The opening of the auditory tube is also found in this portion of the pharynx and is surrounded by a cartilaginous structure known as the tubal torus. Contents of the oropharynx: The major structure here is the palatine tonsil. They are paired (one on each side). There are three muscles associated with the posterior and lateral sides of the pharynx called the superior, middle, and inferior constrictor muscles. Posteriorly they attach to the raphe that itself is attached to the pharyngeal tubercle which is associated with the clivus of the occipital bone. These muscles constrict during swallowing and is innervated by the vagus nerve (CNX) Anteriorly, the superior constictor muscle attaches to the pterygomandibular raphe which extends from the inferior portion of the lateral pterygoid plate down to the mandible. (NOTE: THIS RAPHE IS THE ORIGIN OF THE BUCCINATOR MUSCLE) Anteriorly, the middle constrictor muscle is attached to the hyoid bone and the inferior constrictor muscle is attached to the thyroid cartilage. THE ONLY MUSCLE IN THE HUMAN BODY INNVERVATED BY THE GLOSSOPHARYNGEAL NERVE IS THE STYLOPHARYNGEUS MUSCLE!!!!!!!!!!!!!! (Elevates the pharynx) The pharynogbasilar membrane covers the space between the superior border of the superior constrictor up to the base of the skull. The opening into the larynx is called the aditus of the larynx. The folds around that opening are called the aryepiglottic folds. The piriform recess is a pocket to which foreign particles, such as food, often gets trapped. The salpingopharyngeal fold is located in the nasopharynx and is attached to that tubal torus. The interesting thing about this fold is that it contains muscles (salpingopharyngeus muscles, innervated by the vagus nerve) within it that can help unclog the auditory canal upon swallowing. (I AM THINKING HE MAY HAVE SOME SORT OF CLINICAL SCENARIO ABOUT THIS.... MAYBE ) Three muscles that help in elevating the pharynx are: salpingopharyngeus (CNX), palatopharyngeus (CNX), and stylohyoid (CNVII) muscles. Three nerves come out of the jugular foramen that can be seen associated with the pharynx posteriorly: vagus, spinal accessory (CNXI), and the glossopharyngeal nerve (innervates what muscle?) Of course one would also find the internal jugular vein which just so happens to ORIGINATE AT THE MOUTH of the jugular foramen. THE BLOOD SUPPLY TO THE PHARYNX IS FROM THE ASCENDING PHARYNGEAL ARTERY (BRANCH OF THE EXTERNAL CAROTID ARTERY) AND PHARYNGEAL BRANCHES OF THE INFERIOR THYROID ARTERY. Sensory innervation to the pharynx is primarily from the glossopharyngeal nerve. THE GAG REFLEX IS PRIMARILY GLOSSOPHARYNGEAL NERVE AS WELL.