Larynx Flashcards
What are the four extrinsic laryngeal ligaments?
Thyrohyoid membrane (Lat. and median thyrohyoid ligaments), cricotracheal membrane, hyoepiglottic, and glossoepiglottic.
What level does the thyroid cartilage lie at? What do its superior and inferior horns interact with?
The thyroid cartilage lies at the level of CV4/5. Superior horn is attached to the hyoid by the lat. thyrohyoid ligaments. Inferior horn articulates with the cricoid cartilage.
What attaches to the apex, vocal process, and muscular process of the arytenoid?
Apex - attaches to aryepiglottic lig.
Vocal process - attaches to vocal lig.
Muscular process - attaches to lat. and post. cricoarytenoid mm.
What are the 4 ligaments associated with the epiglottis?
Hyoepiglottic, aryepiglottic, thyroepiglottic, and glossoepiglottic lig.s
What are epiglottic valleculae?
Formed by folds of mucosa overlying the lat. and median epiglottic lig.s
What are the attachments of the quadrangular ligament? Describe it specializations (2).
Anteriorly the quadrangular ligament attaches to the thyroid and epiglottis. Posteriorly attaches to the arytenoids. Superior thickening is referred to as the aryepiglottic lig. Inf. thickening is referred to as the vestibular lig.
What are the attachments of the cricovocal (conus elasticus) lig? Describe its specializations (3).
Attaches inferiorly to the cricoid and superiorly to the thyroid and arytenoid. Superiorly thickens to form the vocal lig.s. Medially and laterally thickens to form the median and lateral cricothyroid lig.s.
Describe the cricothyroid joint
Synovial articulation between the inferior horn of the thyroid and cricoid cartilage. Allows the thyroid to glide forwards and backwards changing the length of the vocal cords.
Describe the cricoarytenoid joint
Synovial articulation between the arytenoids and the cricoid cartilage. Allows for the gliding and rotation of the arytenoids on the cricoid cartilage.
What are the actions of the cricothyroid m?
Pulls the thyroid cartilage anteriorly causing elongation and tightening of the vocal ligaments.
What are the actions of the transverse and oblique arytenoid mm?
Adduct the arytenoids causing approximation of the vocal cords closing the rima glottidis
What are the actions of the posterior cricoarytenoid m?
Abducts the vocal ligaments opening the rima glottidis
What are the actions of the lateral cricoarytenoid m?
Adducts the vocal ligaments closing the rima glottidis
What are the actions of the thyroarytenoid m?
Pulls the thyroid back causing shortening and loosening of the vocal ligaments
What are the actions of the vocalis m?
Most internal portion of the thyroarytenoid m. this is able to perform local changes to the tension in the vocal lig.s
What provides GVE-P and GVA to the supraglottic region and SVA to the epiglottic valleculae?
Internal laryngeal n.
What innervates the laryngeal mm. except for cricothyroid m?
Inferior laryngeal n. External laryngeal n. innervates the cricothyroid m.
Describe the mechanism of the cough reflex
Stimulation of the GVA provided by the internal branch of the superior laryngeal n. causes reflexive contraction of the laryngeal mm. and a cough to force air out of the larynx. If the superior laryngeal n. is ever ablated this reflex will be lost.
What result will injury to external laryngeal n. have on phonation?
Monotonous voice
Where is superior laryngeal n. block administered and why?
Administered in cases of endotracheal tube insertion. Insert the needle halfway between the hyoid bone and thyroid cartilage
What provides GVA, GVE-P, and SVE to the infraglottic region?
Inferior laryngeal n.
What effect would unilateral and bilateral lacerations of the recurrent laryngeal nn. have on phonation?
Unilateral injury would cause hoarseness. Bilateral injury will cause aphonation.
What is the arterial supply to the larynx (3 arteries)?
Superior laryngeal artery - branch of the superior thyroid artery supplies the region above the true folds
Cricothyroid artery - branch of superior thyroid artery supplies the cricothyroid m.
Inferior laryngeal artery - branch of inferior thyroid artery supplies the region below the true folds
