![]() The pharynx plays a role in deglutition, vocalization, and air conduction. from the uvula to the level of the hyoid bone), and the laryngopharynx (extending approx. from the base of the skull to the soft palate), the oropharynx (extending approx. ![]() It is divided into the nasopharynx (extending approx. In addition to contributing to swallowing, it also opens the Eustachian tube to equalise the pressure in the middle ear.The pharynx is a musculomembranous cavity that connects the oral and nasal cavities to the larynx and esophagus.Salpingopharyngeus – arises from the Eustachian tube, inserts into the pharynx.Palatopharyngeus – arises from hard palate of the oral cavity, inserts into the pharynx.Unlike the other pharyngeal muscles, it is innervated by the glossopharyngeal nerve (CN IX).Stylopharyngeus – arises from the styloid process of the temporal bone, inserts into the pharynx.They act to shorten and widen the pharynx, and elevate the larynx during swallowing. The longitudinal muscles are the stylopharyngeus, palatopharyngeus and salpingopharyngeus. Inferior component (cricopharyngeus) has horizontal fibres that attach to the cricoid cartilage.Īll pharyngeal constrictors are innervated by the vagus nerve Longitudinal.Superior component (thyropharyngeus) has oblique fibres that attach to the thyroid cartilage.Inferior pharyngeal constrictor – located in the laryngopharynx.Inserts posteriorly into the pharyngeal raphe.Originates from the stylohyoid ligament and the horns of the hyoid bone.Middle pharyngeal constrictor – located in the laryngopharynx.Inserts posteriorly into to the pharyngeal tubercle of the occiput and the median pharyngeal raphe.Originates from the pterygomandibular ligament, alveolar process of mandible and medial pterygoid plate and pterygoid hamulus of the sphenoid bone.Superior pharyngeal constrictor – the uppermost pharyngeal constrictor.The circular muscles contract sequentially from superior to inferior to constrict the lumen and propel the bolus of food inferiorly into the oesophagus. They are stacked like glasses, which form an incomplete muscular circle as they attach anteriorly to structures in the neck. There are three circular pharyngeal constrictor muscles the superior, middle and inferior pharyngeal constrictors. The muscles of the pharynx are mostly innervated by the vagus nerve – the only exception being the stylopharyngeus (glossopharyngeal nerve). There are two main groups of pharyngeal muscles longitudinal and circular. The laryngopharynx contains the middle and inferior pharyngeal constrictors. It is found posterior to the larynx and communicates with it via the laryngeal inlet, lateral to which one can find the piriform fossae. It is continuous inferiorly with the oesophagus. The most distal part of the pharynx, the laryngopharynx is located between the superior border of the epiglottis and inferior border of the cricoid cartilage (C6). The oropharynx is involved in the voluntary and involuntary phases of swallowing. Waldeyer’s ring is the ring of lymphoid tissue in the naso- and oropharynx formed by the paired palatine tonsils, the adenoid tonsils and lingual tonsil. Palatine tonsils – lymphoid tissue located in the tonsillar fossa (between the palatoglossal and palatopharyngeal arches of the oral cavity).Lingual tonsils – lymphoid tissue at the base of the tongue.The oropharynx is the middle part of the pharynx, located between the soft palate and the superior border of the epiglottis. The posterosuperior nasopharynx contains the adenoid tonsils, which enlarge between 3-8 years of age and then regress. This part of the pharynx is lined with respiratory epithelium ciliated pseudostratified columnar epithelium with goblet cells. It is continuous with the nasal cavity, and performs a respiratory function by conditioning inspired air and propagating it into the larynx. The nasopharynx is found between the base of the skull and the soft palate. The pharynx is comprised of three parts (superior to inferior): It begins at the base of the skull, and ends at the inferior border of the cricoid cartilage (C6). The pharynx is a muscular tube that connects the oral and nasal cavity to the larynx and oesophagus.
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