Pharynx Flashcards
What are the four main muscles of the pharynx and their innervations?
- Constrictors (Superior/Middle/Inferior) - X
- Stylopharyngeus - IX
- Salpingopharyngeus - X
- Palatopharynges - X
What is the only muscle ending in “glosses” that is not innervated by XII?
Palatoglossus - X
What innervates Tensor Veli Palatini? Levator Veli Palatini?
tensor = Trigeminal (V3)
Levator = X
- both involve the soft palate
What is the blood supply to the pharynx?
Ascending Pharyngeal of the Carotid
- ascending Palatine and tonsillar - (facial artery)
- Pharyngeal branches and descending palatine of Maxillary
A 50 year old male presents with a cancerous mass in the lateral wall of his pharynx that is placing pressure on the surrounding structures. He exhibits difficult in rotating his head to the side opposite the lesion, has trouble swallowing coupled with a loss of taste sensation, and cannot shrug his shoulder on the side ipsilateral to the growth. What nerves are affected?
A: 7,8 B. 10,12 C. 9,11 D. 4,5 E. Only 9
C: 9, 11
What does NOLE represent?
the divisions of the Nasal, Oral, Laryngeal, and Esophogeal canal
What is the name of the area in front of the pre-vertebral fascia and behind the buccopharyngeal fascia?
Retropharyngeal space
-Chicken bones can pierce the buccopharyngeal fascia, enter the retropharyngeal space, and cause infection that can reach the heart.
What is the purpose of the Hyoid bone?
The hyoid serves as an anchor point for the tongue (geniohyoid m.)
A broken hyoid is diagnostic of death by strangulation.
Upon swallowing , muscles inserting on the hyoid pull it superiorly forcing the epiglottis closed as it is pushed up into the back of the tongue.
What does the stylohyoid ligament connect?
The stylohyoid ligament connects the styloid with the lesser horn of the hyoid.
What two structures pierce the thyrohyoid membrane? Where are they found?
- internal laryngeal nerve
- superior laryngeal ARTERY
(between thyroid cartilage and the hyoid bone)
- under middle constrictor
Where do all three constrictor muscles insert upon?
raphe of pharynx
Superior Pharyngeal Constrictor
- what is it near?
Origin: pterygoid hamulus
Insertion: median raphe of pharynx
Innervation: 10
The pterygomandibular raphe is the fibrous line of junction between the buccinator and superior constrictor muscles
** It is near the auditory tube ( equalizes air pressure)
Middle Constrictor
Origin: stylohyoid ligament and greater and lesser horns of HYOID bone.
Insertion: median raphe of pharynx.
Innervation: 10
Inferior Constrictor
Origin: thyroid cartilage and cricoid cartilage.
Insertion: median raphe of pharynx.
Innervation: 10
The fibers arising from the cricoid are believed to act as a sphincter, preventing air from entering the esophagus.
All overlap so that bone or food cannot pry them apart**
Buccinator
ACTION:
Aids mastication, tenses cheeks in blowing and whistling, aids closure of mouth
NERVE
Buccal branch of facial nerve (VII)
Remember ! There are 2 buccal nerves—from V for check pain (sensory from Trigeminal V3), from 7 for the buccinator
JOINS THE SUPERIOR CONSTRICTOR VIA RAPHE
Tensor Veli Palatini
ORIGIN:
Scaphoid fossa and medial aspect of spine of sphenoid bone
INSERTION Palatine aponeurosis (via pulley of pterygoid hamulus)
ACTION
Tenses soft palate prior to elevation
NERVE
Nerve to medial pterygoid (main trunk of mandibular nerve - V3)
TENSES THE PALATE = TRIGEMINAL NERVE
Levator Veli Palatini
ORIGIN
Apex of inferior surface of petrous temporal bone and medial rim of auditory tube
INSERTION
Palatine aponeurosis
ACTION
Elevates, retracts and lateral deviates soft palate. May open auditory tube on swallowing
NERVE
Pharyngeal branch of vagus nerve = 10
LIFTS THE PALATE
What is one of the causes of sleep apnea?
Obesity, which can lead to flaccid soft palate (blocks the airway)
Stylopharyngeus
O: Styloid
I: thyroid
A: assists in swallowing ***
N: 9!!
- found between superior and middle constrictors
Mylohyoid
ORIGIN
Mylohyoid line on internal aspect of mandible
INSERTION
Anterior three quarters : midline raphe. posterior quarter: superior border of body of hyoid bone
ACTION
- Elevates hyoid bone
- supports and raises floor of mouth.
- Aids in mastication and swallowing
NERVE Mylohyoid nerve (V3)
Remember the nerve to mylohyoid (V) travels with the inferior alveolar nerve (V) but does not enter the mandible
Hyoglossus
- what nerve travels over this muscle? what artery travels below?
ORIGIN : hyoid bone
INSERTION: tongue
ACTION
Depresses tongue
NERVE = Hypoglossal nerve (XII)
Nerve = Hyoglossus OVER the muscle
Artery = Lingual Artery (behind muscle)
What veins drain 90% of the brain? Through what foramen does the jugular vein travel through?
Jugular and vertebral
- Jugular Foramen
- The sigmoid sinus becomes the jugular vein, which drains the brain or you become insane
The superior laryngeal nerve is a branch off of what cranial nerve? What nerves does it split into? Do both contain sensory components?
- Branch off of X (vagus)
- SLN splits into internal and external laryngeal nerves—-
Internal –no muscles, sensory above cords,
External –no sensory, motor to cricothyroid***
What innervates the cricothyroid?
External Laryngeal nerve
What nerve is sensory ABOVE the vocal chords? Which nerve is sensory BELOW?
above = Internal Laryngeal
below = Recurrent Laryngeal
(external laryngeal = NO SENSORY)
Cricothyroid
ORIGIN cricoid cartilage INSERTION thyroid cartilage ACTION Lengthens and tenses vocal cords by tilting thyroid cartilage forwards NERVE
*External branch of superior laryngeal branch of vagus nerve (X)
The Recurrent Laryngeal recurs around the Aorta on the right side. True or false?
FALSE
Recurrent laryngeal recurs around the AORTA = LEFT SIDE
Right side = around Subclavian artery
- ENTERS INFERIOR PART OF VOICE BOX
What nerve innervates all the muscles of the larynx (except cricothyroid = external branch of superior laryngeal branch of Vagus)?
Recurrent Laryngeal Nerve
What is the function of CN 9?
- 9 wraps around the stylopharyngeus like a stripe on a barber’s pole.
- innervates the stylopharyngeus
- sensory to a little ear pinna,
- drives the parotid gland (GLOAP)
- and via Herring’s nerve helps control blood pressure thru the carotid sinus and body,
- taste sensation to post 1/3 tongue
Some sensation to medial eardrum and throat
What is the function of CN 11?
11 innervates the branchiomeric muscles: sternocleidomastoid and trapezius.
SVE
What is the function of CN 12?
Xll goes thru the
Hypoglossal canal and is motor to all muscles ending in glossus except palatoglossus (X)—Xll has no sensory component
GSE!!!
What is the blood supply to the pharynx?
- Superior thyroid artery (EXTERNAL CAROTID) –> superior laryngeal artery
(penetrates the thyrohyoid membrane along with the internal laryngeal nerve)
- Inferior thyroid artery (THYROCERVICAL TRUNK)–> inferior laryngeal artery and enters the larynx with the recurrent (inferior) laryngeal nerve
Where do chicken bones get stuck in the throat?
Piriform recess
What part of the throat never calcifies?
Epiglottis
How does the nose communicate with the mouth?
If you slit the constrictors open*
Left and right Choanae in the back
+
Turbinates
What muscle helps keep the auditory tube open?
Salpingopharyngeus
What nerve and artery are found under the Inferior Constrictor?
- Recurrent Laryngeal N.
2. Inferior Thyroid A.
You are asked to check the integrity of the trochlear nerve in the right eye of a patient. Starting with the eyes directed straight ahead, you would have the patient look:
Inward, toward the nose and downward
Inward, toward the nose and upward
Toward the nose in a horizontal plane
Laterally in a horizontal plane
Outward, away from the nose and downward
Outward, away from the nose and upward
- Inward toward the nose and upward
To test the superior and inferior recti, a patient needs to turn the eye outward approximately 25 degrees. At this postion, the superior rectus will simply act to raise the eye, and the inferior rectus will lower the eye. To test the superior and inferior obliques, a patient needs to turn the eye inward approximately 50 degrees. When the eye is in this position, the superior oblique muscle will act to lower the eye, and the inferior oblique will act to raise the eye.
The ducts of the lacrimal gland open into the: Superior fornix of the conjunctiva Inferior fornix of the conjunctiva Lacrimal puncta Lacrimal canaliculi Lacrimal lake
Superior fornix of the conductive
The extraocular muscle that does not originate at or near the apex of the orbit is the : Inferior oblique Inferior rectus Levator palpebrae superioris Superior oblique Superior rectus
inferior Oblique
An adolescent boy suffers from severe acne. As is often the case he frequently squeezed the pimples on his face. He subsequently develops a fever and deteriorates into a confused mental state and drowsiness. He is taken to his physician and after several tests a diagnosis of cavernous sinus infection and thrombosis is made. The route of entry to the cavernous sinus from the face was most likely the: Carotid artery Mastoid emissary vein Middle meningeal artery Ophthalmic vein Parietal emissary vein
Opthalmic Vein
If a person looking inward towards their nose is unable to look down, which nerve may be injured? Abducens (CN VI) Inferior division of oculomotor (III) Optic (II) Superior division of oculomotor (III) Trochlear (IV)
Trochlear
- To isolate the superior and inferior recti, the patient needs to turn the eye outward by approximately 25 degrees. This places the superior rectus in position to raise the eye and the inferior rectus in position to lower the eye.
- Turning the eye inward approximately 50 degrees places the inferior oblique in position to raise the eye and the superior oblique in position to lower the eye.
Any manipulation of the superior thyroid artery must be undertaken with care not to damage its small companion nerve, the:
Cervical sympathetic trunk
External branch of the superior laryngeal
Inferior root of the ansa cervicalis
Internal branch of the superior laryngeal
Recurrent laryngeal
Internal branch of Superior Laryngeal
The carotid body is innervated by a branch of the: Glossopharyngeal nerve Hypoglossal nerve Spinal accessory nerve Sympathetic trunk Vagus nerve
Glossopharyngeal
What nerve sits on top of the hyoglossus muscle? What artery is deep to the hyoglossus?
12
- Lingual Artery
What follows the Carotid Artery up through the Carotid Canal?
Sympathetic Chain – follow the vasculature into the head
Sleep apnea is a result of what?
Flaccid soft palate
What innervates the buccinator?
Buccal branch of 7
- aids mastication
What are the origins of the:
Superior Constrictor
Middle Constrictor
Inferior Constrictor
Superior - Medial Plate of Pterygoid
Middle - Greater & lesser horns of Hyoid
Inferior - Thyroid & Cricoid
