anatomy 2: palate/pharynx/larynx

three parts of pharynx

nasopharynx, oropharynx, laryngopharynx

which part of the pharynx is where the digestive and respiratory share a common space

oropharynx

anterior 2/3 of palate is ______, posterior 1/3 is ________

hard; soft

laryngopharynx is posterior to the

larynx

when we swallow, soft palate moves

up and horizontal to close off nasopharyx

soft palate prevents reguritation of

liquid into nasal cavity

what two muscles elevate the soft palate? what are they innervated by?

tensor veli palatini muscle - CN V

levator veli palatini muscle - CN X

tensor veli palatini muscle action

stretches the palate from side to side and makes it stiff

what is the action of the levator veli palatini muscle

lift palate up and backwards to make horizontal

what other two muscles are important in swallowing

palatopharyngeus

palatoglossus muscle

palatopharyngeus and palatoglossus are both innervated by

CN X

palatoglossus action

bring elevated palate and tongue closer together, and decrease height of oral cavity - squeezes food

opening of ______ is located in nasopharynx

auditory tube

muscles of the pharynx are organized into two groups:

constrictors and vertical group

constrictor group

superior constrictor (X)

middle constrictor (X)

inferior constrictor (X)

the constrictor group fires in sequence to make a

peristaltic wave to force food downward

the muscles of the constrictor group generally attach to

their opposite side counterparts

vertical group

palatopharyngeus (X)

slapinogopharyngeus (X)

stylopharyngeus (IX)

vertical group act to

shorten pharynx; pull pharynx up and shorten during swallowing

muscles of vertical group attach to the

posterior margin of thyroid cartilage

origin of superior constrictor

Pterygoid hamulus (of sphenoid bone)

Pterygomandibular raphe (band of connective tissue between hamulus and mandible)

Posterior end of the mylohyoid line of the mandible

insertion of superior constrictor

pharyngeal raphe and pharyngeal tubercle

middle constrictor origin

hyoid bone + stylohyoid ligament

middle constrictor insertion

pharyngeal raphe/opposite side of middle constrictor

inferior constrictor origin and insertion

Originates →

Thyroid cartilage of the larynx

Inserts →

Opposite side of inferior constrictor

the gap above the superior constrictor is for

auditory tube to pass through

constrictor muscles connect to the other side by the

pharyngeal raphe

Palatopharyngeus origin and insertion

Originates from bone to soft palate

Inserts to laryngeal cartilage inside the superior and middle constrictors

Salpingopharyngeus origin and insertion

Origin starts from palatopharyngeus

Inserts at the cartilaginous part of the auditory tube

what can activate the Salpingopharyngeus muscle? what does this cause?

Yawning and chewing can activate this muscle → pulls the auditory tube open → equalize the pressure in the ear (ears opping)

Stylopharyngeus origin and insertion

Originates → outside the pharynx at the styloid process

inserts to the laryngeal cartilage inside the superior and middle constrictors

Innervated by IX

somatic sensory of pharynx: mostly _______. nasopharynx is also innervated by ______. laryngopharnx is also innervated by _______

glossopharyngeal nerve (CN IX), pharyngeal branch of V2, vagus nerve

somatic motor: _______ to stylopharyngeus only. _______ to all other pharyngeal muscles

glossopharyngeal (CN IX)

vagus nerve (CN X)

two phases of swallowing -

voluntary and involuntary

voluntary phase of swallowing ? what muscle is part of voluntary phase?

Squeeze the bolus back to the oropharynx by pushing the tongue up against the soft palate and tongue → done through the palatoglossus muscle → squeeze the bolus backward to the pharynx

involuntary phase of swallowing begins by

bolus contacting pharyngeal mucosa (CN IX/glossopharyngeal) - sensation intiates involuntary phase

soft palate is then stiffened by _____ to _____

tensor pallatini and levator palette toelevate the palate until it makes contact with the back wall of the pharynx to make an air tight and water tight seal → keeps the bolus going in one direction

_________ squeezes and narrows and hits the soft palate, starting perstalsis movement.

Superior constrictor squeezes and narrows and hits the soft palate → starts the peristalsis movement → constrictor muscle squeezes downward and backward

bolus of food will enter the ______ which causes _____ to move downward and cover ______

valeculla, epiglottis, laryngeal inlet

valeculla sits between _______. the two are separated by ______

epiglottis and post 1/3 of tongue; median glossoepiglottic ligament

the geniohyoids and posterior part of the genioglossus pull the _______, which _______. they also act to ________

tongue and hyoid forward, opening the esophogus. they also act to empty the valleculae

when the geniohyoids and genioglossus contract, the

valleculae become more shallow

bolus travels around ______ in ______

laryngeal inlet in the piriform recess

to intiate involuntary swallowing, the

glossopharyngeal and pharyngeal plexus must be intact

infants can breath during nursing because

there is no gap between the soft palate and epiglottis

without the gap, a barrier is formed and

bolus traves around inlet without movement of the epiglottis/closure of inlet

contact between soft palate and epiglottis is lost within

first year of life

dysphagia (difficulty in swallowing) is defined by

delays in the passage of food/liquid bolus at one or more points between the oral cavity and the stomach

based on the problem, dysphagia can be descirbed as having two basic types:

oropharyngeal or esophageal

oropharyngeal dysphagia include problems with getting bolus of food from

oral cavity to the pharynx

oropharyngeal dysphagia can be due to

anything pressing on lumen from outside - abcess, zenkers dierticulum

what is zenkers diverticulum

a bulge or pouch → press forward in the lumen of the esophagus and prevent smooth swallowing

oropharyngeal transport can also be due to

loss of pharyngeal sensory plexus or muscle weakness

what would happen if trigemical nerve was damaged?

innervate tensor velatini muscle → palatal insufficiency → can't get a tight seal → problems with aspirating and regurgitating from the oral pharynx to the nasal pharynx

what would happen in glossopharyngeal nerve (IX) lesion

loss of motor function b/c it supplies the stylopharyngus muscle and loss of sensory function (need it to stimulate swallowing to start the involuntary phase) → sensory is more of a problem

Used to initiate the gag reflex + vomiting reflex → loss of this action

what would happen if vagus nerve was damaged (CN X)

loss of innervation to most of the pharynx muscle + loss of innervation of levator palati → motor problems in swallowing → often results from brain stem damage and strokes

what would happen if hypoglossal nerve (XII) was damaged

provides somatic motor nerve to the tongue → difficult manipulating bolus of food to the oral cavity and oropharynx → difficulty in the voluntary phase

what are some possible factors that can lead to problems with esophageal transport

mechanical obstruction

motility disorders

Mechanical causes → causes that prevent food moving through the esophagus and cause an obstruction →

can be caused by tumors pressing onto the esophagus, cancers on the esophagus, "steakhouse syndrome”

Motility causes → causes that prevent ________. These include _____, which when food and liquid cannot pass through ________

peristalsis or muscle movement in the esophagus → achalasia → food and liquid can’t get through the distal esophagus into the stomach

achalasia can result from

degeneration of the innervation of the esophagus resulting from autoimmune response. may have genetic basis

adams apple is called the

laryngeal prominence located on thyroid cartilage

thyroid cartilage is open

posteriorly

thyroid cartilage and cricoid have _____ between them

synovial joints between it and cricoid cartilage

cricoid cartilage is the _____ and completely ______

base of the larynx, completely encircles airway

trachea has cartilage rings that are

not fully complete

opening between the vocal cords is called the

rima glottis

vestibular ligaments are covered by

vestibular folds

vocal ligament is covered by

vocal folds

vestibular ligament action

minor adduction and abduction

vocal fold action

large ROM

vocal folds regulate the size of

air that goes through → controls the size of the rima glottis

full adduction =

ligaments fully touching eachoither

in what actions do we adduct vocal folds/ligaments

cough, holding breath, swallowing, speaking

cough

Cough → adduct ligaments → build up pressure underneath vocal ligaments by abdominal wall muscles → relax ligaments to exhale air

Swallowing →

pulls the ligaments close to prevent any regurgitation of food during swallowing

speakinig -->

closing airway completely down and forcefully exhaling air through the vocal ligaments → ligaments will vibrate → creates resonance

what actions make ligaments abduct

quiet breathing, exercise

quiet breathing -->

half to ⅔ of the way open

breathing during exercise

open the airway as much as possible to get as much air in as possible

ligaments attach to ______ anteriorly and _______ posteriorly. _____ sits on top of the cricoid cartilage with synovial joints in between them --> regulate the space between __

These ligaments attach to the thyroid cartilage in the front and attached to arytenoid cartilage posteriorly → arytenoid cartilage sits on top of the cricoid cartilage with synovial joints in between them → regulate the space between the vocal ligaments and the tension

laryngitis is ________ which results in _______. Can be due to ____, _____, _____, _____.

swelling and irritation of the larynx → loss of voice

colds or flu, acid reflux, overuse of voice or irritation from allergies or smoke.

signs of reflux larngitis from chronic GERD

laryngeal redness

yellowed vocal folds (edema)

laryngeal mucous

the mucosa lining the laryngeal inlet is extremely touch sensitive - contacting it with foreign material triggers the ______ via _______

Cough reflex → via the internal laryngeal nerve from CN X (sensory limb of cough reflex)

persons who have suffered strokes that damage the sensory component of CN X may have greater risk of

aspiration

what is the motor limb of the cough reflex

abdominal wall muscles, force air out/forceful expiration

vocal cord dysfunction is a disorder where there is a

sudden adduction of the vocal cords (closing the airway) during breathing

vocal cord dysfunction can occur during either _____ or ______ with symptoms that can mimic _______. - ______

inhalation or exhalation with symptoms that can mimic asthma (SOB, stridor, wheezing)

VC dysfunction can affect the voice if it

occurs during speech

vocal cord dysfunction is most common in

young females

the exact cause of vocal cord dysfunction is unknown, but suggested triggers are

GERD,

inhaled allergens/drainage from nasal cavity

anxiety

laryngeal muscles

lateral cricoarytenoid

posterior cricoarytenoid

oblique and transverse arytenoids

cricothyroid

thyroarytenoid and vocalis

Lateral cricoarytenoid origin, insertion, action

Lateral side of larynx

Originates at circocartilage

Inserts at arytenoid

Action → move arytenoid cartilage → adductor → close the airway → most powerful adductor

Narrows laryngeal inlet

what is the most powerful adductor

lateral cricoarytenoid

Posterior cricoarytenoid origin insertion and actoin

Posterior of the larynx

Action → pull the arytenoid cartilage backwards → abductor → opens airway

Only muscle that can open the airway

what is the only muscle that can open airway

posterior cricoarytenoid

Oblique and transverse arytenoid: attaches the ____ to each other, _____ the laryngeal inlet

Attach the arytenoids to each other

Narrows the laryngeal inlet

cricothyroid action

Move the thyroid cartilages together on top of the cricoid cartilage → adducts + stretches out the vocal ligaments→ increases pitch

cricothyroid is innervated by

Innervated by an external laryngeal nerve of the vagus nerve (X)

Thyroartenoid action

Run in parallel with the mucosa of the ligament

Pulls arytenoid cartilages forward → can decrease the pitch