Larynx

Question 1

Larynx skeleton

Answer 1

. Consists of 9 cartilages connected by ligaments and membranes
. All are hyaline except epiglottic that is elastic
. All cartilages covered by mucosa
. Paired: arytenoid, corniculate, and cuneiform
. Unpaired: thyroid, cricoid, and epiglottic

Question 2

Thyroid cartilage

Answer 2

. Formed from 2 plate-like lamina that fuse and leave post. Side open
. Laryngeal prominence: midline projection at C6 from fused lamina
. Oblique line: oblique ridges on lat. surface, attachment for thyrohyoid m. And inf. Pharyngeal constrictor
. Sup. Horn: sup. Projection on post. Side, attached to hyoid bone via thyrohyoid membrane
. Inf. Horn: inf. Projections on post. Sides, attachment for cricoid cartilage at cricothyroid joints

Question 3

Cricoid cartilage

Answer 3

. Complete ring w/ narrow ant. Arch and wider post. Lamina
. Articulate lat. w/ inf. Horns,
. Median cricothyroid ligament spans space tw thyroid and cricoid cartilage ant.
. Articular w/ paired arytenoid cartilages sup.
. Connected to 1st trachea cartilage by cervicobrachial ligament inf.

Question 4

Epiglottic cartilage

Answer 4

. Leaf-shaped, attached to ant. Entrance of larynx post. To root of tongue
. Attaches to thyroid cartilage and you’d bones via ligaments

Question 5

Arytenoid cartilage

Answer 5

. Paired pyramids w/ sup. Projecting apex
. Ant. Projecting vocal process, and lat. muscular process
. Corniculate cartilage sit on apices
. Vocal process is for post. Attachment of vocal ligament
. Muscular process is for attachment of lat. and post. Cricoarytenoid mm.
. Articular w/ cricoid cartilage at cricoarytenoid joints (synovial) on superolat. Edge of cricoid lamina

Question 6

Corniculate and cuneiform cartilages

Answer 6

. Small, mucosa-covered nodules in post. Part of aryepiglottic folds
. Corniculate attach to apices of arytenoid cartilages
. Cuneiform do not attach to other cartilages

Question 7

Thyrohyoid membrane

Answer 7

. Spans space btw hyoid and thyroid cartilage

Question 8

Vocal ligaments

Answer 8

. Elastic fibers attaching to laminae of thyroid cartilage ant. And vocal process of arytenoid cartilages post.
. Vocal folds/cords consist of vocal ligaments covered by mucosa

Question 9

Conus elasticus

Answer 9

. Poorly defined term that comprises the med. and lat. cricothyroid ligaments plus vocal ligaments

Question 10

Median cricothyroid ligament

Answer 10

. Ant. Midline structure that spans space btw laminae of thyroid and cricoid cartilages

Question 11

Lat. cricothyroid ligaments

Answer 11

. Paired

. Extend lat. from vocal ligaments (sup. Free margins of ligaments) to sup. Border of cricoid cartilage

Question 12

Cricothyroid joints

Answer 12

. Synovial joints from lamina of cricoid an inf. Horns

. Rotary and gliding movements

Question 13

Cricoarytenoid joints

Answer 13

. Synovial joints btw lamina of cricoid and bases of arytenoid cartilages
. Rotary and gliding movements

Question 14

Extrinsic mm. Of larynx

Answer 14

. Attach to hyoid or thyroid laminae
. Elevate/depress entire larynx
. Elevators: thyrohyoid, stylopharyngeus, palatopharyngeus, suprahyoid mm.
. Depressors: sternothyroid, omohyoid, and sternohyoid mm.

Question 15

During swallowing, the larynx is ____

Answer 15

. Elevated

. So epiglottis covers inlet of larynx and food move spost. To esophagus

Question 16

Rima glottidis

Answer 16

. Opening btw vocal folds

. Shape varies w/ vocal fold movement

Question 17

What muscles open rima glottidis

Answer 17

Post. Cricoarytenoid m.

Question 18

What closes rima glottidis?

Answer 18

. Arytenoid m.
. Lat. cricoarytenoid m.
. Thyroarytenoid m.

Question 19

What decreases tension on vocal folds?

Answer 19

Thyroarytenoid m.

Question 20

What inc. tension on vocal cords?

Answer 20

Cricothyroid m.

Question 21

Intrinsic mm. Of larynx innervation

Answer 21

. Inf. Laryngeal n. Except cricothyroid m. That is done by external branch of sup. Laryngeal n.

Question 22

Intrinsic mm. Of larynx

Answer 22

. Cricothyroid m. 
. Post. Cricoarytenoid m. 
. Lat. cricoarytenoid m. 
. Arytenoid m. 
. Thyroarytenoid m. 
. Vocalis m.

Question 23

Cricothyroid attachments and action

Answer 23

Attachments: the ant. arch of the cricoid cartilage and inf. border and horn of thyroid cartilage; visible on the external and internal surfaces of the thyroid laminae
A: tenses and elongates the vocal ligaments
by tilting the thyroid cartilage anteriorly

Question 24

Post. Cricoarytenoid m. Attachments and action

Answer 24

Attachments: the post. surface of the cricoid lamina and muscular process of arytenoid cartilage
A: abducts the vocal folds (opens the rima
glottidis)

Question 25

Lat. cricoarytenoid m . Attachments and action

Answer 25

Attachments: lat. side cricoid cartilage and muscular process of the arytenoid cartilage
A: adducts the vocal folds (closes the rima
glottidis)

Question 26

Arytenoid m. Attachments and action

Answer 26

Attachments: posterior surfaces of adjacent arytenoid cartilages
A: pulls the arytenoid cartilages together (closes the rima glottidis)

Question 27

Thyroarytenoid m. Attachments and action

Answer 27

Attachments: internal surface of thyroid laminae and median cricothyroid ligament ant. and arytenoid cartilage post.
A: The thyroarytenoid m. decreases tension on the vocal cords by pulling thyroid and arytenoid cartilages closer together

Question 28

Vocalis m. Attachments and action

Answer 28

Attachments: the vocal process of the arytenoid cartilages, the vocal ligaments, and the thyroid angle
A: adjusts tension in the vocal folds.

Question 29

Glottic incompetence

Answer 29

. Due to partial or unilateral paralysis of vocal folds

. Inc. risk of aspiration

Question 30

Ant. Surface of larynx

Answer 30

. Lies deep to strap mm. And thyroid gland

. Laryngeal prominence (adam’s apple) palpable and visible in midline of neck at C6

Question 31

Post. Surface of larynx

Answer 31

. Inlet of larynx: sup. Opening from laryngopharynx, slopes posteroinf.
. Valleculae: paired recesses btw root of tongue and epiglottic
. Piriform recesses: in laryngopharynx lat. to cricoid cartilage

Question 32

Inlet of larynx boundaries

Answer 32

. Epiglottis ant. And sup.
. Aryepiglottic folds lat.
. Mucosa covering arytenoid cartilages post.

Question 33

Internal larynx

Answer 33

. 2 pairs prominent folds visible
. Vestibular (ventricular/false): sup. Located pair, consist of mucosa overlying vestibular ligaments
. Vocal folds (true): inf. Located pair, consist of mucosa overlying vocal ligaments and vocalis mm.
. Vestibule: space btw inlet of larynx and vestibular folds
. Ventricle: narrow space btw vestibular and vocal folds
. Infraglottic cavity: space inf. To vocal folds, continuous inf. W/ trachea

Question 34

Glottis

Answer 34

. Vocal folds plus rima glottidis

Question 35

Sensory innervation of larynx

Answer 35

. Mucosa sup. To vocal folds via internal branch of sup. Laryngeal n. (Branch off sup. Laryngeal n. At hyoid bone that pierces thyrohyoid membrane to enter larynx)
. Mucosa inf. To vocal folds via recurrent laryngeal n. That becomes inf. Laryngeal n. Sup. To cricothyroid joint

Question 36

Motor innervation of larynx

Answer 36

. Inf. Laryngeal n. Innervates all intrinsic mm. Except cricothyroid
. Cricothyroid m. Innervated by external branch of sup. Laryngeal n.

Question 37

Blood supply to larynx

Answer 37

. Sup. Laryngeal a.: branches from sup. Thyroid a, courses w/ internal branch of sup. Laryngeal n. Through thyrohyoid membrane to enter larynx
. Inf. Laryngeal a.: branches from inf. Thyroid a., courses w/ recurrent laryngeal n. And inf. Laryngeal n. Into larynx
. Sup. And inf. Laryngeal aa. Anastomose w/in larynx

Question 38

What may be damaged during thyroid surgery?

Answer 38

. Recurrent laryngeal nn.
. Severing of 1 causes hoarseness when speaking
. Severing of both causes suffocation due to loss of function in mm. That open rima glottidis