Larynx Flashcards
The larynx is continuous with the ____ posteriorly and superiorly, and with the ____ inferiorly
pharynx; trachea
The larynx is located at vertebral body levels ___-___
C3-C6
What are the 3 functions of the larynx?
- passage of air
- sphincter (close RT during swallowing)
- phonation
The laryngeal skeleton (9 cartilages) is formed by ____ cartilage, with the exception of the epiglottic cartilage formed by ____ cartilage
hyaline; elastic
This is the largest of the laryngeal cartilage. It consists of two quadrangular laminae fused anteriorly with the adam’s apple
Thyroid cartilage
The oblique line is a ridge on the posterolateral sides of the thyroid cartilage for attachment of what 3 muscles?
sternothyroid, thyrohyoid, inferior pharyngeal constrictor
This is the only cartilage to completely encircle the airway. It has a thin anterior arch and an enlarged lamina posteriorly. The lamina articulates with the arytenoid cartilages
Cricoid cartilage
This cartilage is a paired set, located posteriorly in the larynx, sitting atop the lamina of the cricoid. It has a three-sided pyramidal shape with a posterolateral projection for muscular attachment, an anterior projection for vocal ligaments, and a superior apex.
Arytenoid cartilage
This cartilage is paired, sits atop the apices of the arytenoid cartilages and is conical-shaped.
corniculate cartilages
This cartilage is single, paddle or teardrop-shaped, located posterior to the root of the tongue and hyoid bone, and is broad with a free superior part and an inferior stalk attached to the internal surface of the angle between laminae anteriorly
epiglottic cartilage
The larynx grows from birth to childhood. At puberty, laryngeal cartilages enlarge and laryngeal prominences become more obvious in males due to influence of ____
testosterone
These joints are synovial articulations of inferior horns of thyroid cartilage and the lamina of cricoid cartilage
cricothyroid joints
In regards to the cricothyroid joints, as thyroid cartilage tilts anteriorly, the vocal folds are ____
tensed
note: posterior tilting loosens vocal folds
These joints are synovial articulations of arytenoid cartilage and the lamina of cricoid cartilage
cricoarytenoid joints
In regards to cricoarytenoid joints, the arytenoid cartilages slide transversely and pivot on cricoid cartilage which results in what?
abduction or adduction of the vocal processes
The thyrohyoid membrane connects the ____ border of the thyroid cartilage to the ____ and ____ ____ of the hyoid bone
superior; body; greater horns
The openings in the thyrohyoid membrane allow passage of what vessels/nerve
superior laryngeal vessels; internal laryngeal nerve
This ligament attaches the inferior surface of the cricoid to the upper border of the 1st tracheal ring
cricotracheal ligament
This ligament passes from anterior midline of epiglottis to the body of the hyoid bone. It limits epiglottic movement posteriorly
hyoepiglottic ligament
The thryoepiglottic ligament attaches the ____ of the epiglottic cartilage to thyroid cartilage
stalk
This is an elastic membrane that attaches to the superior surface of cricoid cartilage and projects superomedially inside the thyroid cartilage
conus elasticus
The upper, free edges of conus elasticus are thickened to form ____ ____ which attach postiorly to the ____ ____ of the arytenoid cartilages and anteriorly to the thyroid laminae
vocal ligaments (cords); vocal processses
The thickened anterior portion of conus elasticus is the ____ _____ ligament
median cricothryoid
This ligament is a thin submucosal CT that supports the aryepiglottic fold. It is attached between epiglottic and arytenoid cartilages.
quadrangular ligament
The free superior margin of the quadrangular ligament forms the _____ ligament, the free inferior margin forms the ____ ligament
aryepiglottic; vestibular
The vestibular ligament attaches where?
below the apex of the arytenoid cartilage and to the thyroid cartilage above the vocal ligament
The superior opening of the larynx is called what?
laryngeal inlet
The vestibule of the larynx is the space between the ____ folds
aryepiglottic
The space between the vestibular folds is called the ____ _____
rima vestibuli
The narrow space between the vestibular and vocal folds is called the laryngeal ventricle. It extends anterosuperiorly as the ____, a blind pouch with numerous mucous glands
saccule
The mucosa of the ventricle continues inferiorly to cover the vocal ligaments to form the ____ ____
vocal folds (true vocal cords)
The opening between two vocal folds is ____ _____
rima glottidis
The shape of rim glottidis is ____ during normal respiration and ____ during forced respiration, and _____-like during phonation
narrow; wide; phonation
For the following intrinsic muscle of the larynx, give the origin, insertion, and action:
Posterior cricoarytneoid muscle
origin: lamina of cricoid cartilage
insertion: muscular process of arytenoid cartilage
action: abduction of vocal folds -> opens rima glottidis
For the following intrinsic muscle of the larynx, give the origin, insertion, and action:
Lateral cricoarytenoid muscle
origin: cricoid cartilage
insertion: muscular process of arytenoids
action: adducting vocal folds -> closes rima glottidis
For the following intrinsic muscle of the larynx, give the origin, insertion, and action:
Transverse arytenoid muscle
attachments: spans between arytenoid cartilages posteriorly
action: assists with adduction of vocal folds
For the following intrinsic muscle of the larynx, give the origin, insertion, and action:
oblique arytenoid muscle
origin: muscular process of arytenoids
insertion: apex of opposite arytenoid
action: assists with adduction of the vocal folds
For the following intrinsic muscle of the larynx, give the origin, insertion, and action:
Cricothyroid muscle
origin: arch of cricoid cartilage
insertion: inferior edge of thyroid cartilage
action: stretches/tenses vocal folds (allowing pitch to be raised)
For the following intrinsic muscle of the larynx, give the origin, insertion, and action:
Thyroarytenoid muscle
origin: anterior thyroid cartilage (arises internally)
insertion: anterolateral surface of arytenoid cartilage
action: relaxing vocal folds
For the following intrinsic muscle of the larynx, give the origin, insertion, and action:
Vocalis muscle
origin: arytenoid cartilage (vocal processes)
insertion: vocal ligament
action: fine tunes tension on vocal folds
For the following intrinsic muscle of the larynx, give the origin, insertion, and action:
Thyroepiglottic muscle
origin: extension of thyroarytenoid muscle
insertion: aryepiglottic fold
action: sphincter for the aditus
The superior laryngeal artery, which supplies most of the upper part of the larynx is usually a branch from this artery
superior thyroid artery
The inferior laryngeal artery supplies the lower part of the larynx after arising form the inferior thyroid artery which is a branch from what?
thyrocervical trunk
The inferior laryngeal artery ascends with what nerve?
recurrent laryngeal nerve
The superior laryngeal vein drains through the ____ ____ vein into the ____ ____ vein
superior thyroid; internal jugular
The inferior laryngeal vein drains through the ____ ____ vein to the ____ ____ vein
inferior thyroid; left brachiocephalic
Sensory innervation of the larynx is entirely from branches of the vagus nerve. From the aditus to the vocal cords, the mucosa is supplied by the _____ ____ nerves; below the vocal cords the mucosa is innervated by the ____ ____ nerves
internal laryngeal; recurrent laryngeal
Motor innervation to the cricothryoid muscle is by the ____ ____ nerve, while all other muscles in the larynx are innervated by the _____ ____ nerves
external laryngeal; recurrent laryngeal
Motor neurons to laryngeal muscles, as well as preganglionic parasympathetic neuron cell bodies are in the ____ ____
brain stem
What are the two branches of superior laryngeal nerve? What is the continuation of the recurrent laryngeal nerve?
superior laryngeal nerve: internal and external laryngeal nerves
recurrent laryngeal nerve: inferior laryngeal nerve
Damage to this nerve can cause desensitization of superior larynx and hence more likely to have difficulty swallowing yielding laryngeal foreign bodies and choking
internal laryngeal nerve
Damage to this nerve can paralyze cricothryoid muscle, resulting in a weak voice, lowered pitch, or monotone voice
external laryngeal nerve
Damage to this nerve can result in vocal fold paralysis
inferior laryngeal nerve
Damage to this nerve results in the abductors being more affected than adductors which is known as Semon’s law. This yields an adducted position of affected cords.
recurrent laryngeal nerve
