the neck and larynx

Question 1

where is the superficial cervical fascia

Answer 1

lies between dermis and deep cervical fascia

Question 2

what does the superficial cervical fascia contain

Answer 2

superficial neurovascular structures and lymph nodes
CT especially subcutaneous fat
muscles, namely platysma

Question 3

what are the 4 layers of deep cervical fascia

Answer 3

investing layer of deep cervical fascia
prevertebral layer of deep CF
pretracheal layer of DCF
carotid sheath

Question 4

why do we have fascial planes

Answer 4

so muscles contract when theyre meant to

Question 5

what is investing fascia

Answer 5

most superficial layer of DF
encloses/invests the trapezius and SCM muscles

Question 6

glands muscles and thickenings of investing fascia

Answer 6

G: parotid, submandibular
M: SCM, trapezius
T: omohyoid, digastric

Question 7

describe the pre-tracheal layer of fascia

Answer 7

located within the ant. region of the neck
encloses thyroid, trachea and oesophagus

Question 8

describe the pre-vertebral layer of fascia

Answer 8

forms a tubular sheath which surrounds vertebral column and associated muscles

Question 9

describe the carotid sheath

Answer 9

surrounds internal jugular vein, common carotid artery and vagus nerve

Question 10

what are the triangles of the neck

Answer 10

2 main paired triangles divided into smaller paired triangles
content incl. muscles, nerves, arteries, veins, and lymph nodes

Question 11

describe the digastric triangle

Answer 11

aka submandibular
bounded: sup. by inferior boundary of the mandible
posteriorly by anterior part of posterior belly of digastric
anteriorly by the lateral aspect of the anterior belly of digastric

Question 12

describe the submental triangle

Answer 12

aka suprahyoid triangle
borders: sup. ant belly of digastric
inf. - body of hyoid bone
ant. by the midline
floor= mylohyoid

Question 13

function of the mylohyoid muscle

Answer 13

if mandible is fixed in position = elevated hyoid
if hyoid fixed in position = depresses mandible

Question 14

artery vein and nerves in carotid triangles

Answer 14

common carotid artery - bifurcates into the external and internal carotid arteries
internal jugular jein - responsible for venous drainage of head and neck
cranial nerves - CNVII, CNIX, CNX, CNXI, CNXII

Question 15

what is the cervical plexus

Answer 15

network of nerves located within the neck. has both motor and sensory branches

Question 16

describe the development of the larynx

Answer 16

in infants and most nonhuman mammals - epiglottis touches uvula so that there is a respiratory channel from nose -> larynx and 2 lateral swallowing pathways from mouth -> pyriform recesses -> oesophagus
larynx descends during growth separating epiglottis and uvula - common pathway for breathing and swallowing

Question 17

consequence of developing larynx

Answer 17

cannot swallow and breathe simultaneously
increased risk of choking
louder voice
greater range of sounds

Question 18

describe the larynx

Answer 18

3 unpaired cartilages
1 bone
3 paired cartilages

Question 19

describe the thyroid

Answer 19

incomplete posteriorly
forms laryngeal prominence (adam’s apple)
only anchored at two points - can tilt

Question 20

describe the cricoid

Answer 20

only complete cartilaginous ring around airway
large flat lamina posteriorly and thin arch anteriorly
articulates with inf. horn of thyroid and arytenoids

Question 21

what is the joint between inf. horn of thyroid and cricoid called

Answer 21

cricothyroid joint

Question 22

describe the arytenoid

Answer 22

pyramidal shaped with 3 processes:
apex (sup.) -> articulates with corniculate cartilages
muscular process (posterolateral) -> for muscle attachment
vocal process (anterior)-> attachment of a vocal ligament

Question 23

describe the thyrohyoid membrane

Answer 23

between hyoid and sup. border of thyroid cartilage
holes for entry of nerves/vessels

Question 24

describe the cricothyroid membrane

Answer 24

dome-shaped membrane attaching to:
sup. border of cricoid (inf)
internal aspect of thyroid (ant.)
vocal processes of arytenoids (post)

Question 25

describe the quadrangular membrane

Answer 25

paired, attaches to:
lateral border of epiglottic cartilage (ant.); lateral border of arytenoid (post)
2 free borders:
upper=aryepiglottic fold
lower=vestibular ligament (when covered with epithelium = false vocal fold)

Question 26

what moves the larynx

Answer 26

extrinsic and intrinsic muscles

Question 27

what do vocal ligaments attach to

Answer 27

internal aspect of thyroid in midline
vocal processes of arytenoids

Question 28

function of movement of larynx

Answer 28

breathing, prevent entry of food/liquid, valsalva manoeuvre, vibration of vocal ligaments as air passes through rima glottidis allows phonation

Question 29

function of intrinsic muscles

Answer 29

tilt thyroid ant, and post - stretching/ relaxing vocal ligaments
rotate the arytenoids - moving the vocal ligaments together or apart

Question 30

describe the cricothyroid muscle

Answer 30

tilts thyroid anteriorly, stretching the ligaments -> increases the pitch of voice

Question 31

attachment and function of post. and lat. cricoarytenoid muscle

Answer 31

muscular process of arytenoid -> post/lat aspects of cricoid -> rotate arytenoids
post CA-> abduct vocal cords
lat CA -> adducts vocal folds

Question 32

function of interarytenoid muscles

Answer 32

join arytenoids -> adduct arytenoids closing posterior part of rima glottidis

Question 33

describe vocalis

Answer 33

attaches along length of vocal ligament and modulates its tension

Question 34

describe thyroarytenoid

Answer 34

pulls thyroid and arytenoids closer together relaxing vocal ligament and reducing pitch

Question 35

describe aryepiglotticus

Answer 35

pulls epiglottis inferiorly over laryngeal inlet during swallowing

Question 36

what innervates the larynx

Answer 36

CNX