[3] Larynx

specialized organ that provides …

protective sphincter at the inlet of the air passage

if the protective function is disturbed, … results and …

laryngeal incompetence results; and food and fluid may be aspirated into trachea

responsible for the …

voice production (voice box or organ of phonation)

… of the larynx help in swallowing

upward and downward movements

above it communicates with the …

laryngopharynx

below it is continuous with the …

trachea

functions of the larynx

1. phonation

2. respiration

3. protection

4. deglutition

located in the … at the level of …

anterior neck at the level of C3 to C6 vertebrae

in children and in females it lies …

at a higher level

till puberty its size in both males and females is …

more or less the same 

after puberty larynx in the male …

rapidly grows and becomes larger than the larynx in the female

in males the … makes the voice louder and low-pitched

characteristic pubertal growth of the angle of thyroid cartilage (Adam’s apple)

females the pubertal growth of larynx does not differ much from a child, hence the pitch of the voice …

is high in both females and children

length of the larynx in males and females

males - 44 mm

females - 36 mm

skeleton of the larynx:

1. made up of:

2. cartilages are connected by … and … and moved by …

3. lined by …

1. three unpaired and three paired cartilages

2. connected by membranes and ligaments and moved by muscles

3. mucous membrane

skeleton of the larynx: name the unpaired cartilages

1. thyroid

2. cricoid

3. epiglottis 

skeleton of the larynx: name the paired cartilages

1. arytenoid

2. corniculate

3. cunieform

what structure forms the epiglottis

the caudal part of hypobranchial eminence

the remaining cartilages of larynx are derived from …

4th to 6th pharyngeal arches

thyroid cartilage:

1. size

2. made up of what type of cartilage

3. consists of …

4. size of the angle in males and females

1. largest laryngeal cartilage

2. hyaline cartilage

3. two laminae which meet in the midline at the thyroid angle or Adam's apple

4. 90 degrees in males and 120 degrees in females

thyroid cartilage:

there is oblique line on outer surface of the each lamina for attachments to …

1. sternothyroid muscle

2. thyrohyoid muscle

3. inferior constrictor muscle

thyroid cartilage:

posterior borders of each lamina is drawn upward into a … and downward into …

1. superior cornu

2. inferior cornu

thyroid cartilage:

posterior borders provides insertions to …

1. salpingopharyngeus muscle

2. palatopharyngeus muscle

3. stylopharyngeus muscle

thyroid cartilage:

posterior surface of the thyroid cartilage in the median plane provides attachment to:

1. thyroepiglottic ligament

2. pair of vestibular ligament

3. pair of vocal ligament

cricoid cartilage:

1. shaped like ...

2. lies below ... at the level of ...

3. made up of what type of cartilage

1. a signet ring

2. below the thyroid cartilage at the level of C6

3. hyaline cartilage

cricoid cartilage:

4. has a narrow ... and a broad ...

5. the lateral surface is a ... with ... of the thyroid cartilage

6. posteriorly the upper border of the lamina articulates with the ...

7. it is the only cartilage which ...

4. narrow anterior arch and a broad posterior lamina

5. circular facet for articulation with the inferior cornu of the thyroid cartilage

6. base of the arytenoid cartilage

7. completely encircles the larynx

epiglottis:

1. shape

2. type of cartilage

3. situated ...

4. its lower end is connected with the ... by the ...

5. it is connected in front with ...

1. leaf shaped

2. elastic cartilage

3. situated behind the hyoid bone and base of the tongue

4. thyroid cartilage by the thyroepiglottic ligament

5. the body of the hyoid bone

epiglottis:

6. sides of the epiglottis are connected to the ... by ...

7. upper end is ... and forms the ...

8. anterior surface is connected to the ... by ...

9. the depression on each side of the median fold is called the ...

6. arytenoid cartilages by aryepiglottic folds

7. free and forms the upper boundary of the laryngeal inlet

8. tongue by the medial and lateral glossoepiglotic folds

9. vallecula

arytenoid cartilage:

1. how many in number

2. shape

3. situated

4. type of cartilage

5. has an ... above which supports the ... and ... cartilages

6. base articulates with ...

1. 2 in number

2. pyramidal

3. situated at the back of the larynx

4. hyaline cartilage

5. apex, corniculate and cuneiform

6. lamina of cricoid cartilage

arytenoid cartilage:

what are the two processes that project from the base, directions it projects and gives attachment to …

1. vocal process - projects horizontally forwards, gives attachment to the vocal ligament

2. muscular process - projects laterally, gives attachment to the posterior and lateral cricoarytenoid muscles

corniculate cartilages (of Santorini):

1. what are they

2. articulate with …

3. lie in the …

1. two small nodules

2. articulate with the apex of the arytenoid cartilage

3. posterior part of ary-epiglottic fold

cuneiform cartilages (of Wrisberg):

1. what are they

2. articulate with

3. lie in the ...

1. two rod like pieces of cartilage

2. the corniculate cartilages

3. posterior part of the ary-epiglottic folds just above the corniculate cartilages

what are the laryngeal joints

1. crico-thyroid joints

2. crico-arytenoid joints

3. aryteno-corniculate joints

crico-thyroid joint:

1. situated between the …

2. what type of joint

3. what type of movement does it permit

1. inferior cornu of thyroid and side of cricoid cartilage

2. plane synovial joint

3. rotatory and gliding movements

crico-arytenoid joint:

1. situated between the …

2. what type of joint

3. what type of movement does it permit

1. base of the arytenoid and lateral part of the upper border of the lamina of the cricoid cartilage

2. plane synovial joint

3. permits rotatory (to abduct or adduct the vocal cords) and gliding (to close or open the posterior part of glottis) movements

aryteno-corniculate joint:

1. situated between the …

2. what type of joint

3. what type of movement does it permit

1. between the arytenoid and corniculate cartilage

2. plane synovial joint

3. no functional significance

thyrohyoid membrane:

1. extends from the …

2. thickened in the midline to form the …

3. posterior borders of the membrane also thickened to form the …

4. the lateral thyrohyoid ligament on each side contains a … called …

5. the thyrohyoid membrane is pierced by … and …, which lies beneath the …

1. upper border of thyroid cartilage below and posterior surface of the hyoid bone above

2. median thyrohyoid ligament

3. lateral thyrohyoid ligaments

4. small nodule of elastic cartilage called cartilago-triticea

5. internal laryngeal nerve and superior laryngeal vessels, which lies beneath the mucous membrane of the larynx

quadrangular membrane:

1. extends between the …

2. its thickened lower margin forms the …

1. epiglottis and arytenoid cartilages

2. vestibular ligament

cricotracheal ligament:

connects the … with the …

cricoid cartilage with the first tracheal ring

thyroepiglottic ligament:

connects … to …

narrow lower end of epiglottis to the posterior surface of thyroid angle

hyoepiglottic ligament:

connects … with the …

posterior aspects of hyoid with the anterior surface of upper end of epiglottis

cricothyroid ligament:

1. from the … to the …

2. upper thickened border of cricothyroid ligament is called …

3. anterior end of each vocal ligament is attached to the …

4. posterior end of each vocal ligament is attached to the …

1. lower border of thyroid cartilage to the cricoid cartilage in the midline

2. vocal ligament

3. deep surface of the thyroid angle

4. arytenoid cartilage

laryngeal cavity:

extends from … to the … where it is continuous with the …

inlet of the larynx to the lower border of the cricoid cartilage where it is continuous with the lumen of the trachea

laryngeal cavity:

boundaries

1. anterior - epiglottis

2. posterior - interarytenoid fold

3. on each side - aryepiglottic fold

laryngeal cavity:

divided into 3 parts

1. vestibule or upper part

2. ventricle or sinus of larynx - middle part

3. infraglottic compartment - lower part

vestibule / upper part of the laryngeal cavity:

1. extends from the …

2. vestibular folds project … which is a …

3. what is the gap between the vestibular folds called

1. upper border of the epiglottis to the vestibular folds

2. project medially which is a thickened lower portion of the quadrangular membrane

3. rima vestibuli

ventricle or sinus of larynx / middle part of the laryngeal cavity:

1. what is it

2. what colour are the vocal folds and what does it contain

3. what is the saccule of the larynx

4. what structure does the saccule of the larynx lead to

5. what is the saccule of larynx is provided with and what is its purpose

1. elliptical space between vestibular

2. vocal folds are white and contain vocal ligament

3. narrow blind diverticulum of mucous membrane between the vestibular fold and the lamina of thyroid cartilage

4. leads to sinus of the larynx

5. mucous glands, whose secretion lubricates the vocal cords - oil can of the larynx

ventricle or sinus of larynx / middle part of the laryngeal cavity:

1. what is the rima glottidis

2. lined by …

3. devoid of …

4. what structure lies inferior to the rima glottidis

5. extends from … to the …

6. its walls are formed by …

1. gap between the vocal folds in front and the vocal process of arytenoid cartilages behind

2. stratified squamous epithelium

3. sub mucosa

4. infraglottic compartment

5. vocal folds to the lower border of the cricoid cartilage

6. cricothyroid ligament and cricoid cartilage

muscles of the larynx are divided into:

1. extrinsic muscles

2. intrinsic muscles

extrinsic muscles include:

1. elevators (suprahyoid)

2. depressors (infrahyoid)

extrinsic muscles:

what are the elevator muscles

1. digastric

2. thyrohyoid

3. stylohyoid

4. mylohyoid

4. geniohyoid

extrinsic muscles:

what are the depressor muscles

1. sternothyroid

2. sternohyoid

3. omohyoid

what are the intrinsic muscles of the larynx

1. cricothyroid

2. posterior cricoarytenoid

3. lateral cricoarytenoid

4. transverse arytenoid

5. oblique arytenoid

6. thyroarytenoid

7. vocalis

8. thyroepiglotticus

9. aryepiglotticus

cricothyroid: origin, insertion, action

1. origin - side of the cricoid cartilage

2. insertion - lower border of the inferior cornu of the thyroid cartilage

3. action - tenses vocal cords

posterior cricoarytenoid: origin, insertion, action

1. origin - back of cricoid lamina

2. insertion - muscular process of arytenoid cartilage

3. action - abducts the vocal cords

lateral cricoarytenoid: origin, insertion, action

1. origin - upper border of cricoid cartilage

2. insertion - muscular process of arytenoid cartilage

3. action - adducts the vocal cord

transverse arytenoid: origin, insertion, action

1. origin - back of arytenoid cartilage

2. insertion - back of the opposite arytenoid cartilage

3. action - closes the posterior part of the rima glottidis by approximating arytenoid cartilages

oblique arytenoid: extends from …

extends from the muscular process of one arytenoid cartilage to the vocal process of opposite arytenoid cartilage

thyroarytenoid: origin, insertion

1. origin - inner surface of thyroid cartilage

2. insertion - arytenoid cartilage

vocalis: extends from, action

1. it extends from the vocal process of arytenoid cartilage to the deep surface of thyroid angle

2. action - relaxes the vocal cords

aryepiglotticus: extends from, action

1. extends from the arytenoid cartilage to the side of epiglottis

2. action - close the laryngeal inlet

thyroepiglotticus: origin, insertion, action

1. origin - medial surface of thyroid cartilage

2. insertion - lateral margin of the epiglottis

3. action - widens the inlet

function of the intrinsic muscles of the larynx

alter the shape of inlet of larynx, rima vestibuli and rima glottidis

intrinsic muscles and their action

1. cricothyroid - tenses the vocal cord

2. posterior cricoarytenoid - opens the rima glottidis

3. lateral cricoarytenoid - closes the rima glottidis

4. transverse arytenoid - closes the rima glottidis

5. oblique arytenoid - closes the rima glottidis

6. thyroarytenoid - relax the vocal cord

7. vocalis - relax the vocal cord

8. thyroepiglotticus - opens the inlet of the larynx

9. aryepiglitticus - close the inlet of the larynx

development of the muscles of the larynx

4th - 6th pharyngeal arches

nerve supply of the muscles of the larynx

superior laryngeal and recurrent laryngeal nerves (branches of Vagus)

sensory nerve supply of the larynx:

1. up to the vocal folds (including the vocal fold)

2. below the vocal folds

1. internal laryngeal nerve

2. recurrent laryngeal nerve

motor supply of the larynx:

1. all intrinsic muscles

2. exception = cricothyroid

1. recurrent laryngeal nerve

2. external laryngeal nerve

what is Semon's law:

in progressive lesions of the … nerve the abductors of the … (…) are first to be paralysed and last to recover as compared to the adductors. This is because the nerve supplying the abductors are longer and has less thresh-hold, hence these branches are affected first

1. recurrent laryngeal

2. vocal cords (posterior crico-arytenoids)

blood supply of the larynx:

1. vocal folds and above

2. below the vocal folds

1. superior laryngeal vessels

2. inferior laryngeal vessels

lymph vessels drain to …

deep cervical lymph nodes

examination of larynx

laryngoscopy

infection and inflammation of larynx

laryngitis

describe the rima glottidis and phonation

narrowest antero-posterior cleft of the laryngeal cavity

boundaries of the rima glottidis and phonation

1. in front - angle of thyroid cartilage

2. behind - interarytenoid folds of mucous membrane

3. on each side - vocal folds in the anterior three-fifth and vocal process of arytenoid cartilage in the posterior three-fifth

subdivision of the rima glottidis and phonation:

1. inter-membranous part - in the anterior three-fifth, between the vocal folds

2. inter-cartilaginous part - in the posterior one-fifth, between the vocal process of arytenoid cartilage

shape of the rima glottidis

varies with the movements of the vocal cords

rima glottidis in quiet breathing:

1. intermembranous part is

2. intercartilagenous part is

3. as a whole the glottis is

1. triangular

2. rectangular

3. pentagonal

rima glottidis in full inspiration: the glottis … and becomes … shaped due to …

1. widens

2. diamond shaped

3. abduction of vocal cords

rima glottidis during high pitched voice: is reduced to a … due to … 

1. linear chink

2. adduction of both intermembranous part intercartilagenous part

rima glottidis during whispering:

1. intermembranous part is …

2. intercartilagenous part is …

3. thereby rima glottidis becomes … shaped

1. highly adducted

2. separated by triangular gap

3. inverted funnel shaped