HS2-10 Pharynx Larynx Flashcards
What structures does the pharynx connect?
nasal + oral cavities connected with esophagus + larynx
What is the superior border of the pharynx?
base of skull
What is the inferior border of the pharynx? (2)
inferior border of cricoid cartilage (anterior)
C6 vertebra (posterior)
The pharynx serves as a passageway for
air (from nasal cavity)
food (from oral cavity)
What are the three subdivisions of the pharynx?
nasopharynx
oropharynx
laryngopharynx
What are the boundaries of the nasopharynx?
base of skull → soft palate
What are choanae?
structures that connect nasopharynx to nasal cavity
What is the pharyngotympanic tube?
(a.k.a. auditory or Eustachian tube)
tube that connects pharynx to ear
What is the torus tubarius?
ridge of cartilage around the opening of the auditory/Eustachian/pharyngotympanic tube
What is the salpingopharyngeal fold?
inferior continuation of torus tubarius, formed by underlying muscle
What are the boundaries of the oropharynx?
soft palate → epiglottis
What are fauces?
structures that connect the oropharynx to the oral cavity
What structures form the fauces? (2)
palatoglossal arches
palatopharyngeal arches
What are the valleculae of the epiglottis?
bilateral depression between root of tongue and epiglottis
Broadly speaking, what is the function of the laryngopharynx?
region where pathway for air and food get separated
What are the boundaries of the laryngopharynx?
epiglottis → inferior border of cricoid cartilage
What are the piriform recesses?
spaces on either side of the laryngeal bulge into the pharynx
What are the two groups of muscles associated with the pharynx?
pharyngeal constrictors
pharyngeal elevators
What is the function of the pharyngeal constrictors?
peristalsis results in movement of food bolus in direction of esophagus
What is the origin of the pharyngeal constrictors?
ligaments/skeletal elements close to lateral margins of nasal/oral cavities + larynx
What is the insertion of the pharyngeal constrictors?
pharyngeal raphe (midline of posterior pharynx)
What are the three pharyngeal constrictors?
superior pharyngeal constrictor
middle pharyngeal constrictor
inferior pharyngeal constrictor
What is the orientation of the pharyngeal constrictor muscles?
circular orientation
What is the orientation of the pharyngeal elevator muscles?
longitudinal orientation
What is the function of the pharyngeal elevator muscles?
contraction results in elevation and shortening of pharynx
What are the three pharyngeal elevators?
stylopharyngeus
palatopharyngeus
salpingopharyngeus
What are the origin and insertion of the stylopharyngeus?
origin = styloid process
insertion = pharyngeal wall
What are the origin and insertion of the palatopharyngeus?
origin = hard palate + palatine aponeurosis
insertion = pharyngeal wall
What are the origin and insertion of the salpingopharyngeus?
origin = cartilage of pharyngotympanic tube
insertion = pharyngeal wall
The entire pharynx is covered by
a mucous membrane that is continuous with the mucous membrane of adjacent spaces, such as the oral and nasal cavities
What makes up the pharyngeal plexus?
sensory fibers from CN IX
motor fibers from CN X
All pharyngeal muscles, with one exception, are innervated by
the pharyngeal plexus
What is the exception to the rule that all pharyngeal muscles are innervated by the pharyngeal plexus?
stylopharyngeus, which is innervated by CN IX
What provides sensory innervation for the mucous membrane of the pharynx? (3)
mostly from pharyngeal plexus
but also from maxillary division of trigeminal nerve (CN V2) for nasopharynx
and superior/recurrent laryngeal nerves (branches of CN X) for laryngopharynx
What is the primary lymphatic tissue structure found in the pharynx?
pharyngeal lympathic ring a.k.a. tonsillar ring
What structures make up the tonsillar ring?
pharyngeal tonsils
tubal tonsils
palatine tonsils
lingual tonsils
Where are pharyngeal tonsils found?
at roof of nasopharynx
Where are the tubal tonsils found?
at opening of pharyngotympanic/auditory/Eustachian tube
Where are the palatine tonsils found?
between palatoglossal and palatopharyngeal arches
Where are the lingual tonsils found?
at root of tongue
What structures pass between the superior and middle pharyngeal constrictors?
stylopharyngeus muscle
CN IX
What structures pass between the middle and inferior pharyngeal constrictors?
superior laryngeal vessels
internal laryngeal nerve
[both are going into the laryngopharynx]
What structures pass below the inferior constrictor?
reucrrent laryngeal nerve
inferior laryngeal vessels
What is the retropharyngeal space?
space between posterior wall of pharynx and vertebral column
What is tonsillitis?
inflammation of the palatine tonsils (which are in common parlance just called the tonsils)
What is adenoiditis?
inflammation of pharyngeal tonsils
Adenoiditis can affect what other structures in the pharynx/larynx?
infection can spread to tubal tonsils, which swells and closes pharyngotympanic tube and can spread infection to middle ear
What is the anatomical location of the larynx?
ventral to laryngopharynx
inferior to hyoid bone
superior to trachea
What are the functions of the larynx? (2)
separation of food and air pathways
phonation
What are the four primary skeletal elements of the larynx?
unpaired thyroid cartilage
unpaired cricoid cartilage
paired arytenoid cartilages
epiglottis
What anatomical structure is commonly referred to as the Adam’s apple?
laryngeal prominence of thyroid cartilage
What connects the thyroid cartilage to the hyoid bone?
thyrohyoid membrane
What structure connects the cricoid cartilage and the thyroid cartilage?
cricothyroid membrane
What structure connects the cricoid cartilage and the first cartilaginous ring of the trachea?
cricotracheal ligament
What are the arytenoid cartilages?
three-sided pyramids that sit on top of the cricoid cartilage
The epiglottis is attached to what cartilage?
epiglottis is attached to thyroid cartilage via stalk
What structures demarcate the interior of the larynx?
laryngeal inlet → inferior border of cricoid cartilage
What two folds are found on the interior of the larynx?
vestibular folds (false vocal folds)
vocal folds
What is the layered organization of the vocal folds, from superficial to deep?
mucous membrane (superficial)
vocal ligament
vocal muscle (deep)
What is the vestibule (of the larynx)?
region between inlet of larynx and vestibular folds
What are ventricles (of the larynx)?
recesses that extend laterally between vestibular and vocal folds
What is the glottis?
vocal apparatus of the larynx
The glottis consists of (2)
vocal folds
rima glottidis
What is the rima glottidis?
opening between vocal cords
Describe how the shape of the rima glottidis contributes to function. (3)
completely closed = phonation
narrow opening = quiet respiration
wide opening = forced respiration
The cavity below the vocal folds of the larynx is called
the infraglottic cavity
The intrisic muscles of the larynx can be subdivided into what four groups?
adductors of vocal ligaments
abductor of vocal ligaments
tensors of vocal ligaments
relaxer of vocal ligaments
What are the three adductors of vocal ligaments?
lateral cricoarytenoid muscle
transverse cricoarytenoid muscle
oblique cricoarytenoid muscle
How do the adductors of the vocal ligaments function?
close rima glottidis by rotating arytenoid cartilages and sliding them medially on lamina of cricoid cartilage
What is the abductor of the vocal ligaments?
posterior cricoarytenoid muscle
How does the abductor of the vocal ligaments function?
opens rima glottidis by rotating arytenoid cartilage and sliding them laterally on lamina of cricoid cartilage
What are the tensors of the vocal ligament?
cricothyroid muscle
vocalis muscle
How does the cricothyroid muscle function as a tensor of the vocal ligaments?
increases angle between thyroid cartilage and cricoid cartilage → stretches vocal ligaments → inceased pitch
How does the vocalis muscle function as a tensor of the vocal ligaments?
lies below vocal ligaments and fine-tunes their tension
What is the relaxer of the vocal ligament?
thyroarytenoid muscle
How does the thyroarytenoid muscle function as a relaxer of the vocal ligaments?
pulls arytenoid cartilages closer to thyroid cartilage
All intrinsic muscles of the larynx, with one exception, are innervated by
the recurrent laryngeal nerve (branch of CN X)
What is the exception to the rule that all intrinsic muscles of the larynx are innervated by the recurrent laryngeal nerve?
cricothyroid muscle = innervated by external branch of superior laryngeal nerve (branch of CN X)
What provides sensory innervation superior to the vocal folds?
internal branch of superior laryngeal nerve
What provides sensory innervation inferior to the vocal folds?
recurrent laryngeal nerve
In what cases would a cricothyrotomy be performed?
in emergency circumstances when something standard like an intubation can’t be performed
What is a cricothyrotomy?
insertion of tube or catheter into trachea through cricothyroid membrane
In the context of swallowing, what is the default position of the esophagus and airway? (2)
airway is open
entrance to esophagus closed by upper esophageal sphincter
Is swallowing voluntary or involuntary?
both — initial steps are voluntary, but then subsequent steps are involuntary
What are the three phases of swallowing?
oral phase
pharyngeal phase
esophageal phase
What happens in the oral phase?
oral preparation phase = food masticated + mixed w/ saliva
oral propulsion phase = bolus propelled into pharynx
What happens in the pharyngeal phase? (7)
soft palate elevates → closes off nasal cavity
vocal folds close rima glottidis
arytenoid cartilages tilt forward to protect rima glottidis
suprahyoid and thyroid muscles contract → epiglottis tilts and covers laryngeal vestibule
upper esophageal sphincter opens
pharyngeal elevators contract → pharynx shortens
pharyngeal constrictors contract → peristaltic movement
How long does the pharyngeal phase take?
less than a second
What happens in the esophageal phase?
peristaltic movement, along with gravity, carries bolus into stomach
Damage to the recurrent laryngeal nerve (by a tumor, for example) will result in what clinical presentation?
hoarseness of voice
Where is the palatoglossus muscle found?
under the mucosa of the palatoglossal fold/arch
Where is the palatopharyngeus muscle found?
under mucosa of palatopharyngeal fold/arch
What important structure can be easily damaged if you were to pierce through the piriform recess?
carotid sheath
What provides motor innervation to the stylopharyngeus?
CN IX
What provides motor innervation for the pharyngeal plexus?
CN X
What provides sensory innervation for the pharyngeal plexus?
CN IX
What are the intrinsic muscles of the larynx?
thyroarytenoid muscle
vocalis muscle
cricothyroid muscle
lateral cricoarytenoid muscle
transverse/oblique arytenoid muscles
posterior cricoarytenoid muscle
What pair of muscles tense and relax the vocal ligaments?
cricothyroid muscle (tense)
thyroarytenoid muscle (relax)
What is the function of the posterior cricoarytenoid muscle?
rotates arytenoid cartilages to abduct vocal folds
What is the function of the lateral cricoarytenoid muscle?
rotates arytenoid cartilages to adduct vocal folds
What are the function of the transverse and oblique arytenoid muscles?
pull arytenoid cartilages together to adduct vocal folds
What provides motor innervation to the larynx?
recurrent laryngeal nerve (of CN X) [except for cricothyroid, which is innervated by the external laryngeal nerve of CN X]
What provides sensory innervation to the larynx? (2)
superior larynx = internal laryngeal nerve of CN X
inferior larynx = recurrent laryngeal nerve of CN X
What nerve initiates the cough reflex?
internal laryngeal nerve of CN X
What is a classic sign of recurrent laryngeal nerve damage?
hoarse voice
