Phonation Flashcards
biological functions of the LARYNX
- protects from foreign objects
- valving to shut off airflow for behaviors in which fixation of the thorax is necessary
NON-biological functions of the LARYNX
- sound source
- provides the source for voiced speech
hyoid bone
*structure of the larynx* most superior part of the larynx located at the root of the tongue only bone in the larynx palpate with hands to determine firmness, size, shape, and location held in position by hyoid sling attachment for laryngeal muscles - 23 non-paired, non-articulate with any other bone
cartilages of the larynx
9 TOTAL
thyroid - 1 cricoid - 2 epiglottis - 1 arytenoids - 2 cuneiform - 2 corniculate - 2
landmarks of thyroid cartilage
thyroid notch - palpable notch at midline
laminae - plate
angle of thyroid - more acute in males
anterior attachment for vocal folds
inferior horn (cornu): extends toward cricoid
superior horn (cornu): extends toward hyoid
cricoid cartilage
signet ring
above the top - more tracheal ring
landmarks:
- anterior arch (thinnest): “bottom” of ring shape
- posterior quadrate laminae large square-shaped surface - lateral articular facets for cricothyroid joint
- superior circoid notch: posterior-superior landmark between between arytenoids
arytenoid cartilages
- ride on cricoid, base & 3 sides
landmarks: - vocal processes - extends anteriorly near the midline provides point of attachment for vocal folds & ligaments
- apex: where the corniculates sit, aryepiglottic fold attached
- muscular process: extends out to the side, provides a point of attachment of the PCA & LCA muscles
corniculate cartilages
“cap” on arytenoids - vestigial cartilages
- sits on top
function: perhaps assists in force adduction
epiglottis
midline, leaf-like cartilage
stalk extends down into larynx
functionally closes off larynx when necessary
cuneiform cartilages
embedded in aryepiglottis folds
- -> floaters
- -> support & stiffen aryepiglottic folds - especially functional in closing & opening larynx during swallow
cricoarytenoid joint
*laryngeal joint* cricoid articular facet arytenoid facet (concave) saddle joint: base of arytenoid permits some rotation (in horizontal plane) & rocking (anteriorly - posteriorly) & gliding (laterally-medially) allows folds to be adducted and abducted
cricothyroid joint
laryngeal joint
between lateral cricoid surface & inferior horn of the thyroid
increase tension on vocal folds
used for pitch adjustment
rock forward: increases tension (increase between arytenoids & anterior thyroid)
superglottal space
vestibule: area above the false vocal folds
epiglottis in front
aryepiglottic fold = superior margin of vestibule
ventricular folds = inferior boundary of aditus
pyriform sinus
bounded laterally by thyroid cartilage & membrane
food trapped during swallow - esophagus doesn’t open
UES - Upper Esophageal Sphincter
valleculae
“little valleys”
between root of tongue & epiglottis
food trapped during swallow if swallow is passive
laryngeal ventricle
aka laryngeal sinus
between true & false vocal folds
inside = mucous glad
infraglottal space
superior margin = vocal fold
inferior margin = cricoid cartilage
lined with ciliated beating epithelium from bronchi all the way to the vocal folds
vocal folds (plicae vocalis)
beneath false folds
under ventricle
attach interior of thyroid angle
made of 2 muscles, ligament, epithelial membrane
extrinsic muscles
one attachment to laryngeal structure, one attachment outside
intrinsic muscles
origin & insertion are within the larynx
muscles attached to structure only within the larynx
adjustment for phonation
actions: adduction, abduction, tensor, relaxer
5 - LCA, IA, PCA, CT, thyroarytenoid
Lateral cricoarytenoid muscle (LCA)
instrinsic muscle
attaches to cricoid & arytenoid
main muscle for closing the vocal folds
origin: superior lateral surface, cricoid
course: up & back
insertion: muscular process arytenoid
function: adduct vocal folds & increase medial compression
innervation: x vagus recurrent laryngeal nerve
transverse arytenoid
origin: lateral margin, posterior arytenoid
course: laterally
insertion: lateral margin of opposite arytenoid
function: adduct vocal folds
innervation: x vagus recurrent laryngeal
oblique arytenoid
origin: posterior base of muscular process
course: obliquely up
insertion: apex of opposite arytenoid
function: adducts vocal fold
innervation: x vagus recurrent laryngeal nerve
posterior cricoarytenoid (PCA)
origin: posterior cricoid lamina
course: up & out
insertion: muscle process of arytenoid
function: abducts vocal folds
innervation; x vagus recurrent laryngeal nerve
cricothyroid (CT)
cricothyroid pars recta
cricothyroid pars oblique
muscles run from anterior surface of cricoid to anterolateral, internal surface of thyroid
cause vocal folds to elongate
muscles cause sliding in anterior-post direction
CT pars oblique
course: superiorly & posteriorly
- short, fat pair of muscles causing movement about the cricothyroid joint
- -> downward tilting of thyroid or upward tilting of cricoid
CT pars recta
course: vertical
same as pars oblique
thyroarytenoid (TA)
main mass referred to as vocal folds
runs from anterior commissure on deep surface of thyroid cartilage (just below thyroid notch) back to vocal process of arytenoids
innervation: x vagus recurrent laryngeal nerve
thyromuscularis
lateral-most portion of vocal folds (muscular process of arytenoid)
function: relax vocal fold
thyrovocalis muscle
medial-most portion of vocal folds (vocal process of arytenoid)
function: tense vocal folds
suprahyoids (Laryngeal Elevators)
muscles that attach to the hyoid (4) and structures above hyoid - tongue (2) digastrics stylohyoid mylohyoid geniohyoid
infrahyoids (laryngeal depressors)
muscles that attach to hyoid and structures below hyoid
sternohyoid
omohyoid
sternothyroid
digastricus anterior
elevate and forward
origin: inner surface mandible
course: medially and down
insertion: hyoid via intermediate tendon
function: draws hyoid up
innervation: v trigeminal nerve
digastricus posterior
elevate and back
origin: mastoid process of temporal bone
course: medially and down
insertion: elevate and retract hyoid
innervation: VII facial nerve
stylohyoid
elevate and retract
origin: styloid process of temporal bone
course: medially down
insertion: corpus hyoid
function: elevate and retract hyoid
innervation: VII facial nerve
geniohyoid
elevate and forward
origin: inner surface of mandible on mental spines
course: back and down
insertion: corpus hyoid
function: elevate hyoid, depress mandible
innervatiokn: XII hypoglossal & C1
mylohyoid
elevate and forward
origin: mylohyoid line of inner mandible
course: fanlike median fibrous raphe and hyoid
insertion: corpus hyoid
function: elevate hyoid, depress mandible
innervation: V trigeminal
omohyoid (superior head)
2 bellies from upper border of scapula by way of an intermediate tendon at the sternum to the greater horn of the hyioid origin: corpus hyoid course: down insertion: intermediate tendon function: depress hyoid innervation: c1 note the nontraditional origin/insertion
omohyoid (inferior head)
origin: upper border scapula
course: down & laterally
insertion: intermediate tendon
function: depress hyoid
innervation: C2, C3
note the nontraditional origin/insertion
sternothyroid
origin: manubrium sterni
course: up
insertion: oblique line of thyroid cartilage
function: depress laryx
innervation: spinal C1
sternohyoid
from the manubrium to the body of the hyoid
thyrohyoid
origin: oblique line of thyroid cart
course: up
insertion: greater horn, hyoid
function: depress hyoid and elevate larynx
innervation: spinal C1
epithelium
superficial lamina propria
intermediate lamina propria
deep lamina propria
intermediate & deep = vocal ligaments
cover-body concept of vocal-folds
cover = epithelial and connective tissue layers
body = muscle layer
thyrovocalis + thyromuscularis
squamous epithelium (SE)
outer layer
maintains shape of vocal folds
protects vocal folds
helps keep vocal folds hydrated (barrier to dehydration)
basement membrane (second layer)
between epithelium and superficial lamina propria
holds epithelium to superficial layer of lamina propria
made up of collagen: fibrous & strong
lamina propria (LP)
connective tissue that lies beneath mucosal epithelia throughout body
superficial lamina propria (SLP)
third layer
lamina prorpia consists of extracellular matrix (nonliving structural tissue, found in connective tissues)
mostly loose fibrous and elastic components in a matrix
is actually a “space” or “matrix”
“mass of soft gelatin”
cushions vocal folds
intermediate lamina propria (ILP)
third layer
adds elastic mechanical integrity
consistency of a “bundle of soft rubber bands”
it is composed of mostly elastic fibers
deep lamina propria (DLP)
fourth layer
not as elastic
composed of mostly collagenous fibers
contributes to the durability of the layer
thyrovocalis
fifth layer
passive & active qualities
passively: consistency of “stiff rubber bands”
active: contractile properties control stiffness
layers contribute to vibratory characteristics of vocal folds
outer: maintain structure
basement: attaches epithelial tightly to SLP
SLP: gelatinous, cushion
ILP: highly elastic
DLP: strong
muscle adjusts tension
indirect laryngoscopy
uses a “mirror-on-a-stick”; common
direct laryngoscopy
rigid endoscope inserted into patient’s oropharynx - highest quality view
fiber optic endoscopy
fiber optic transmission of light, more flexible, more comfortable
stroboscopy
rigid scope, strobe allows view of movement of vocal folds
electromyorgaphy (EMG)
wires attached to laryngeal muscles (surface of pins) to measure voltage change with associated muscle action
