Question | Answer |
The pharynx communicated superiorly with the nasal cavity via the ____, anteriorly with the ___ ____, laterally with the middle ear cavity via the _____ tubes, anterioinferiorly with the larynx via the ____, and posteroinferiorly with the ____ directly. | Choanae, oral cavity, eustachian, auditus, esophagus |
What are the three main sections of the pharynx? | Nasopharynx, orpharynx, and laryngopharynx |
* What are the borders of the nasopharynx? What important structures are found in here? | From nasal choana to tip of soft palate. Opening of the auditory (Eustachian) tube, salpingopharyngeal fold, pharyngeal tonsils (e.g. adenoids), tubal tonsils |
* What are the borders of the orpharynx? What important structures are found in here? | From palatoglossal arch and the soft palate to the epiglottis. Palatopharyngeal arch, tonsilar fossa, platine tonsils, lingual tonsils. |
* What are the borders of the laryngopharynx? What important structures are found in here? | From level of C4-C6 vertebrae that is posterior to the larynx. Epiglottis, aryepiglottic folds, piriform recess |
Name the (6) muscles that are found in the pharynx. | 3 external, circular constrictor muscles: superior constrictor, middle constrictor, inferior constrictor. 3 internal longitudinal suspensory muscles: stylopharyngeus, palatopharyngeus, salpingopharyngeus muscles |
What are the attachments of the superior, middle, and inferior constrictor muscles of the pharynx | Sup: Origin-from medial pterygoid plate, insert-post. into median pharyngeal plate. Middle: orig-from lesser and greater cornu of hyoid, insert-into median pharyngeal raphe. Infer: Origin-from thyroid cartilages, insert-post. into median pharyngeal raphe |
What structure supplies oall of the constrictor muscles of the pharynx? | The pharyngeal plexus formed by pharyngeal sensory branches of the glossopharyngeal CNIX, motor branches from the vagus nerve CNX, and postganglionic symphatetics from the superior cervical ganglion |
What is the primary action of the constrictor muscles? | Constrict pharynx during swallowing and propel food into the esophagus |
Where does the stylopharyngeus muscle orgiinate and insert? | Origin: medial side of the base of the styloid process. Insert: posterior border of the thyroid cartilage. |
Where does the palatopharyngeus muscle orginate and insert? | Origin: posterior border of hard palate. Insert: posterior border of thyroid cartilage and side of pharynx and esophagus |
Where does the salpingopharyngeus muscle originate and insert? | Origin: cartilaginous portion of eustachian tube. Inserts: fubers of stylopharyngeys and palatopharyngeus muscles on the posterior border of the thyroid cartilage. |
What nerves supply the pharyngeal internal logitudinal suspensory muscles? What is the action of these muscles? | Stylopharyngeus muscle is supplied by CN IX. Palatopharyngeus and salpingopharyngeus mm supplied by the pharyngeal plexus of nerves. They elevate the larynx during speaking and raise + expand pharynx during swallowing |
Describe the 1st stage of deglutition (muscle movements) | Voluntary, bolus is pushed from mouth into oropharynx by the movements of the tongue |
Describe the 2nd stage of deglutition (muscle movements) | Involuntary and rapid: constrictors and longitudunal muscles move bolus through oropharynx into laryngopharynx into esophagus; prevented from entering nasopharynx by soft palate (raised); raise hyoid and thyroid cartilages-->epiglotis closed |
Describe the 3nd stage of deglutition (muscle movements) | Inferior constrictor muscle pushes food into esophagus; peristaltic waves of smooth muscle continue to move bolus through GI |
What are the three primary functions of the larynx? | Respiratory, phonatory, reflexive and voluntary sphincteric function |
What two structures is the larynx located between? | Trachea and hyoid bone |
Where is the upper laryngeal cavity (supraglottal region)? | From the tip of the epiglottis to the vestibular folds |
Where is the middle laryngeal cavity (glottal region)? | From the vestibular folds to the vocal folds |
Where is the lower laryngeal cavity (infraglottal region)? | From the true vocal cords to the lower border of the cricoid cartilage |
What is the aditus? | The opening into the larynx / trachea |
What is the function and location of the aryepiglottic folds? | They are found laterally to the epiglottis (mucuous membranes); prevent epiglottis from folding over when asleep |
Where are the arytenoid cartilages found? | Inferiorly to the aryepiglottic folds; keep the opening stiff |
Where are the false vocal cords located? | In the vestibular region (area between the auditus and the vestibular folds) |
Where are the vocal folds (true vocal colds) located? | Strung between the thyroid angle and vocal processes of the arytenoid cartilage |
Where are the ventricles? | In the lateral space betwee the false and true vocal folds |
What is the glottis? | It is the narrowest space between the two true vocal folds (narrowest part of the larynx). Abduction: gets larger. Aduction: get smaller |
What is the rima glottis? | The medial borders of the true vocal cords |
What are the (6) cartilages that make up the laryngeal skeleton? | Unpaired: thyroid, cricoid, epiglotic. Paired: arytenoid, cuneiform, corniculate |
Describe the major landmarks of the thyroid cartilage | Laminae: flat surface where the thyroid wraps around (anteriorlateral). Laryngeal prominents: adam's apple. Thyroid angle: anterior part, helps deepen voice in males. Superior thyroid notch: superior. Superior and inferior horns/cornua (psterolateral) |
Describe the shape and landmarks of the cricoid cartilage | Located immediately inferior to thyroid, but anterior is narrow and posterior is broad. It is a continous (signet) ring structure. Lamina for muscle attachement is posterior. Crycothyroid and crycoarytenoid articular surface posterior |
Describe the shape and function of the arytenoid cartilages | Pyramidal--base: sits post-sup. surface of cricoid. Apex articulates with corniculate cart's. Vocal process: points ant. and articulates with vocal folds. Muscular process points posterior, attaches to muscles. Cartilege swivels on base to tense cords. |
What is the function of the Cuneiform and corniculate cartilages? | Keep the aryepiglottic folds patent |
Where is the thyrohyoid membrane? What passes through it? | Connects the hyoid bone and the thyroid cartilage (located anteriorly). Pierced by the superior laryngeal artery and internal laryngeal nerve. |
Where is the cricotracheal membrane? | Between anterior surface of the cricoid cartilage (superior) and trachea (inferior) |
What membrane lines the inner part of the larynx? | The intrinsic membrane. The superior part is the quadrangular membrane, the infraglottal part is named the conus elasticus) |
If you were to make a cricothyrotomy, what structure would you be piercing? Where would you be located? | In the space between the cricoid and the thyroid (covered by the cricothyroid membrane); it would be supraglotteal and above the thyroid gland |
* * What are the extrinsic laryngeal muscles? | Supra and infrahyoid muscles. Used for phonation and deglutition |
* * what are the two intrinsic laryngeal muscle groups? What are the main functions of these two groups? | Sphincteric (aditus and ventricular folds) and the respiratory and phonetic group (strap muscles that act on the laryngeal articulations to change the openings and length of the vocal folds). |
* * What are the sphincteric muscles of the larynx? | Aryepiglottic, oblique arytenoids, thyroepiglottic, and thyroarytenoid |
* * What does the aryepiglottic muscle do? | When it contracts, it constricts the aditus, making it smaller |
* * What does the oblique arytenoid m. do? | Same as the aryepiglottic muscle (make the aditus muscle smaller) |
* * What does the thyroepiglottic muscle do? | Makes the aditus flare out (open out) |
* * What does the thyoarytenoid muscle do? | Makes the aditus flare out (open out) |
* * What does the posterior cricoarytenoid mucle do? | Abducts the vocal folds (moves them apart) |
* * What does the lateral cricoarytenoid mucle do? | Adducts the vocal folds (moves them in, together) |
* * What does the transverse arytenoid m. do? | Adducts the vocal folds, reducing the size of the glottus |
* * What does the cricothyroid muscle do? What nerve innervates it? | Lengthens and tenses the vocal folds, increasing pitch (higher). External laryngeal (from CN X)-->this is the only muscle it innervates! |
* * What do the tyroarytenoid m and the vocalis muscles do? | They shorten and relax the vocal folds-->lower pitch (deeper) |
* * What muscles are supplied by the external branch of the superior laryngeal nerve? | It is the motor branch to the cricothyroid muscle |
* * What muscles are supplied by the internal branch of the superior laryngeal nerve? | Sensory to the upper and middle regions of the laryngeal cavity |
* * What structures does the inferior (recurrent) laryngeal nerve supply? | Motor to remaining intrinsic muscles (EXCEPT cricothyroid muscle!); sensory to lower laryngeal cavity (infraglottal region). |