Anatomy Exam 4

Action and innervation of the platysma muscle

tenses skin of inferior face and neck

facial nerve (CN VII)

Borders of the posterior triangle

Anterior: sternocleidomastoid (SCM)

Posterior: Trapezius

Inferior: Clavicle

Floor: Prevertebral fascia, scalene muscles (anterior, middle and posterior), levator scapulae muscle, splenius capitis muscle

Content of the posterior triangle

inferior belly of omohyoid muscle, cervical plexus (C1-C4), roots and trunks of brachial plexus (C5-T1), phrenic nerve (C3-C5), accessory nerve (CN XI), external jugular vein, subclavian vein, subclavian artery and branches

Action and innervation of Sternocleidomastoid (SCM) muscle

together: neck flexion

individual: rotate head to opposite side, lateral flexion of head

accessory nerve (CN XI)

Action and innervation of Trapezius muscle

superior: elevate scapula

middle: adduct scapula

inferior: depress scapula

accessory nerve (CN XI)

Action and innervation of Scalene muscle

elevation of ribs 1 and 2

anterior rami of C3-C7

Action and innervation of Levator scapulae muscle

elevate scapula

dorsal scapular nerve

Action and innervation of Splenius Capitis muscle

together: extension of neck

individual: rotate head to same side

posterior rami of spinal nerves

Action and innervation of Inferior Belly of the Omohyoid muscle

depresses hyoid bone

anterior rami of C1-C3 (ansa cervicalis)

What nerve runs on the anterior scalene muscle? What muscle does this nerve innervate? What cervical spinal nerves make up this nerve?

phrenic nerve

diaphragm

C3-C5

What structure is located between the anterior and middle scalene muscles?

roots of brachial plexus

What does the external jugular vein drain into?

the subclavian vein

What is the relationship between the subclavian artery and the anterior scalene muscles?

1st part of the subclavian artery is medial to the anterior scalene muscle

2nd part of the subclavian artery is posterior to the anterior scalene muscle

3rd part of the subclavian artery is lateral to the anterior scalene muscle

Identify the arteries (and their branches) that come off each of the parts of the subclavian artery.

1st part: vertebral artery, internal thoracic artery, thyrocervical trunk (branches = inferior thyroid, ascending cervical, transverse cervical, suprascapular)

2nd part: costcocervical trunk

3rd part: dorsal scapular artery

What cervical spinal nerves make up the cervical plexus?

anterior rami of C1-C4

What is the relationship between the sternocleidomastoid muscle and cervical plexus?

cervical plexus pierces the posterior border of the sternocleidomastoid muscle

What is the ansa cervicalis? What muscles does it supply?

loop in the cervical, anterior rami of C1-C3

supplies the omohyoid muscle, sternothyroid muscle, and sternohyoid muscle

Borders and content of the Anterior Triangle - Submandibular Triangle

superior: mandible

anterior: anterior belly of the digastric muscle

posterior: posterior belly of the digastric muscle, stylohyoid muscle

submandibular gland, lymph nodes, facial vein and artery, hypoglossal nerve and mylohyoid muscle

Borders and content of the Anterior Triangle - Submental Triangle

superior: mandible

inferior: hyoid

medial: midline of neck

lateral: anterior belly of digastric muscle

branches of facial artery and vein, branch of mandibular nerve (CN V3), mylohyoid muscles, lymph nodes

Borders and content of the Anterior Triangle - Carotid Triangle

superior: posterior belly of digastric muscle

anteroinferior: superior belly of omohyoid muscle

posteroinferior: SCM

common carotid artery, external carotid artery, internal carotid artery, internal jugular vein, vagus nerve, hypoglossal nerve

Borders and content of the Anterior Triangle - Muscular Triangle

superior: hyoid bone

medial: midline of neck

lateral: superior = superior belly of omohyoid muscle, inferior = SCM

infrahyoid muscles, thyroid gland, parathyroid gland, larynx, trachea, pharynx, esophagus

Action and innervation of Anterior Belly of Digastric Muscle

depress mandible

nerve to mylohyoid (branch of CN V3)

Action and innervation of Posterior Belly of Digastric Muscle

elevate hyoid bone

facial nerve (CN VIII)

Action and innervation of Stylohyoid Muscle

elevates hyoid bone

facial nerve (CN VII)

Action and innervation of Mylohyoid Muscle

elevates hyoid bone and depresses mandible

nerve to mylohyoid (CN V3)

Action and innervation of Superior Belly of Omohyoid Muscle

depresses hyoid bone

anterior rami od C1-C3 (ansa cervicalis)

Action and innervation of Sternohyoid Muscle

depress hyoid bone

C1-C3 (ansa cervicalis)

Action and innervation of Sternothyoid Muscle

depress hyoid bone

C1-C3 (ansa cervicalis)

Action and innervation of Thyrohyoid Muscle

depress hyoid bone

C1 via hypoglossal nerve

What does the common carotid artery divide into? At what vertebral level does the division occur?

divides into external and internal carotid artery at C4

What are the contents of the carotid sheath?

medial to lateral: common carotid artery, vagus nerve, internal jugular vein

What are the branches of the external carotid artery? Know the basic routes they take. What is the terminal branch of the external carotid artery?

superior thyroid artery - goes towards thyroid

ascending pharyngeal artery - goes posterior and travels superiorly up pharynx

lingual artery - travels deep under tongue

facial artery - over mandible and vascularizes superficial face

occipital artery - vascularizes posterior skull

posterior auricular artery - travels behind the ear

maxillary artery - largest one, 3 divisions = mandibular, pterygoid, pterygopalatine

superficial temporal artery - temple, terminal branch

What does the internal jugular vein form when combined with the subclavian vein?

internal jugular vein + subclavian vein = brachiocephalic vein

Of the muscles discussed, which are considered suprahyoid or infrahyoid? How would you describe the relationship of these muscles with the hyoid bone?

suprahyoid = above the hyoid bone → anterior and posterior belly of digastric muscle, stylohyoid muscle, mylohyoid muscle

infrahyoid = below the hyoid bone → superior and inferior belly of omohyoid muscle, sternohyoid muscle, sternothyoid muscle, thyrohyoid muscle

Where is the thyroid gland located? What are the parts of the thyroid gland?

thyroid gland located at C6

thyroid cartilage located at C4

2 lobes on the lateral sides, isthmus in the center connecting the 2 lobes, pyramidal lobe from isthmus up to hyoid bone

Where are the parathyroid glands located? How many parathyroid glands are there?

posterior side of thyroid gland

4

What is the arterial supply and venous drainage of the thyroid and parathyroid glands?

arterial supply: superior thyroid artery, inferior thyroid artery

venous drainage: superior, middle and inferior thyroid veins

Trace the drainage of the five groups of superficial lymph nodes

occipital nodes, mastoid nodes - superficial cervical nodes - deep cervical nodes - right and left jugular trunks - right lymphatic duct and thoracic duct

pre-auricular/parotid nodes, submandibular nodes, submental nodes - deep cervical nodes - right and left jugular trunks - right lymphatic duct and thoracic duct

The superficial and deep cervical nodes are located on which blood vessels?

superificial cervical nodes - external jugular vein

deep cervical nodes - internal jugular vein

List the twelve cranial nerves.

Identify which nerves are motor only, sensory only, or both.

For each nerve, what is the overall major function?

Olfactory (CN I) = sensory = smell

Optic (CN II) = sensory = vision

Oculomotor (CN III) = motor = extraocular and eyelid muscles

Trochlear (CN IV) = motor = extraocular muscle

Trigeminal (CN V) = both = V1 (ophthalmic): face sensation, V2 (maxillary): face sensation, V3 (mandibular): face sensation and mastication

Abducens (CN VI) = motor = extraocular muscle

Facial (CN VII) = both = facial expression, taste to anterior 2/3 of tongue, tear and salivary ducts

Vestibulocochlear (CN VIII) = sensory = balance and hearing

Glossopharyngeal (CN IX) = both = taste to posterior 1/3 of tongue, sensation to pharynx, swallowing

Vagus (CN X) = both = taste, sensory information to body viscera, glands to GI tract, swallowing

Accessory (CN XI) = motor = trapezius and SCM

Hypoglossal (CN XII) = motor = tongue muscles

What are the five terminal motor divisions of the facial nerve?

temporal, zygomatic, buccal, mandibular, cervical

Action and innervation of facial expression muscle: Occipitofrontalis

frontal belly = raises eyebrow and wrinkles skin of forehead

occipital belly = pulls scalp posteriorly

facial nerve (CN VII)

Action and innervation of facial expression muscle: Orbicularis Oculi

closes eye - palpebral = gently, orbital = tightly

facial nerve (CN VII)

Action and innervation of facial expression muscles: Zygomaticus Major and Zygomaticus Minor

elevates corner of mouth

facial nerve (CN VII)

Action and innervation of facial expression muscle: Buccinator

compresses cheek against molars

facial nerve (CN VII)

Action and innervation of facial expression muscle: Orbicularis Oris

closes lips

facial nerve (CN VII)

Action and innervation of facial expression muscle: Levator Palpebrae Superioris

elevates superior eyelid

oculomotor nerve (CN III)

What is the parotid gland? Where is it located? What is its innervation? What structures pass through?

largest salivary gland located between the ear and masseter muscle

innervated by glossopharyngeal nerve (CN IX) and auriculotemporal nerve (branch of CN V3 - mandibular nerve)

facial nerve (CN VII), external carotid artery and retromandibular vein pass thru parotid gland

What are the articulations of the temporomandibular joint (TMJ)?

What separates the bony articulations from each other?

temporal bone and mandible

Action and innervation of the mastication muscle: Masseter

elevate (closing the mouth) and retract (moving mandible posterior) mandible

mandibular nerve (CN V3)

Action and innervation of the mastication muscle: Temporalis

elevate (closing the mouth) and retract (moving mandible posterior) mandible

mandibular nerve (CN V3)

Action and innervation of the mastication muscle: Medial Pterygoid

elevate (close the mouth) and laterally deviate (side-to-side movement) mandible

mandibular nerve (CN V3)

Action and innervation of the mastication muscle: Lateral Pterygoid

depress (open mouth), protract (moving mandible anterior), and laterally deviate (side-to-side movement)mandible

mandibular nerve (CN V3)

Which branches of the trigeminal nerve supply sensation to the face?

V1 = ophthalmic

V2 = maxillary

V3 = mandibular

What is the infratemporal fossa? What are its borders? What are its contents?

Wedge-shaped space located at the base of the skull, deep to masseter muscle

contains the 4 muscles of mastication

contains maxillary artery (branches = middle meningeal artery, inferior alveolar artery which exits mandible as mental artery)

contains pterygoid venous plexus which receives drainage from cavernous sinus via small emissary veins

contains mandibular nerve (branches = auriculotemporal nerve, inferior alveolar nerve which exits mandible as mental nerve and gives off the nerve to mylohyoid, lingual nerve)

What is the unique relationship of the auriculotemporal nerve and middle meningeal artery, and between the lingual nerve and chorda tympani nerve?

auriculotemporal nerve encircles the middle meningeal artery

chorda tympani nerve hitches a ride with the lingual nerve

The following nerves come off of which cranial nerve?

Auriculotemporal nerve

Inferior alveolar nerve

Lingual nerve

Chorda tympani nerve

Auriculotemporal nerve, inferior alveolar nerve,and lingual nerve come off of the trigeminal nerve (CN V)

Chorda tympani nerve comes off of the facial nerve (CN VII)

what does the palatoglossal arches connect and what muscle in found here

connects the soft palate and lateral aspect of the tongue

contains the palatoglossus muscle

What do the platopharyngeal arches connect and what muscle can you find here

connects the soft palate and the pharynx

contains the palatopharyngeus muscle

What is located between the palatoglossal and palatopharyngeal arches?

palatine tonsils

What are the five muscles of the soft palate? What is their innervation?

tensor veli palatini - CN V3

levator veli palatini - CN X

musculus uvulae - CN X

palatoglossus - CN X

palatopharyngeus - CN X

What muscles make up the intrinsic and extrinsic muscles of the tongue? What is their innervation?

extrinsic muscles -

genioflossus = CN XII

hyoglossus = CN XII

styloglossus = CN XII

palatoglossus = CN X

What nerves allow for taste sensation? Be specific to which part of the tongue they innervate.

chorda tympani nerve (CN VII branch) = anterior 2/3 of tongue

glossopharyngeal nerve (CN IX) = posterior 1/3 of tongue

What nerves allow for general sensation of the tongue? Be specific to which part of the tongue they innervate.

lingual nerve (CN V3 branch) = anterior 2/3 of tongue

glossopharyngeal nerve (CN IX) = posterior 1/3 of tongue

What are the three divisions of the pharynx? Where are they located in relation to the nasal cavity, oral cavity, and larynx?

Nasopharynx - naval cavity is anterior

Oropharynx - oral cavity is anterior

Laryngopharynx - larynx is anterior

What are the muscles that make up the pharynx? What is their function? What is the innervation of these muscles?

Constrictor Muscles:

Superior Constrictor = CN X

Middle Constrictor = CN X

Inferior Constrictor = CN X

Longitudinal Muscles:

Stylopharyngeus = CN IX

Palatopharyngeus = CN X

Salpingopharyngeus = CN X

The muscles work together to facilitate swallowing and breathing by propelling food and air thru the pharynx

What is the sensory innervation of the pharynx?

Glossopharyngeal nerve (IX)

Describe the following structures of the nasopharynx?

a.    Pharyngeal tonsils/adenoids

b.    Eustachian tube

c.    Torus tubarius

Pharyngeal tonsils/adenoids = masses of lymphoid tissue located at the junction of the roof and posterior wall of the nasopharynx

Eustachian tube = located at the posterolateral wall of the nasopharynx, connecting the middle ear cavity to the nasopharynx

Torus tubarius = mucosal elevation in the lateral wall of the nasopharynx, formed by the underlying cartilage of the pharyngeal end of the Eustachian tube. It is located immediately posterior to the opening of the Eustachian tube

What are the boundaries of the larynx?

anterior = neck musculature

posterior = laryngopharynx

superior = hyoid bone, oropharynx

inferior = trachea

What are the three unpaired of laryngeal cartilage?

thyroid cartilage

cricoid cartilage

epiglottis

What is the function of the epiglottis?

epiglottis moves downward and covers the opening of the larynx

protect the airway by preventing food, liquid, or other foreign objects from entering the trachea

Where would you find the thyrohyoid and cricothyroid membranes?

thyrohyoid membrane = found between the hyoid bone and superior border of thyroid cartilage

cricothyroid membrane = found between the inferior border of thyrohyoid cartilage and superior border of cricothyroid cartilage

What is the difference between vestibular and vocal folds?

vestibular folds= false vocal cords, superior

vocal folds = true vocal folds, inferior

Action of the following intrinsic laryngeal:

Lateral cricoarytenoid

Transverse cricoarytenoid

Oblique cricoarytenoid

Posterior cricoarytenoid

Thyroarytenoid

Vocalis

Lateral Cricoarytenoid, Transverse Cricoarytenoid, Oblique Cricoarytenoid = adduction of vocal cords (produces higher tones)

Posterior Cricoarytenoid = abduction of vocal cords (produces lower tones)

Thyroarytenoid, Vocalis = relax/shorten vocal cords (produces lower pitch)

Innervation of the intrinsic laryngeal muscles

Vagus nerve (CN X) : superior laryngeal nerve and recurrent laryngeal nerve

What is the nasal septum? Formed from which bones or structures?

divides the 2 nasal cavities

formed by septal cartilage, vomer bone and perpendicular plate of ethmoid bone

What is the pathway of airflow through the nasal cavities?

1) anterior naris (nostrils)

2) vestibule (open space)

3) nasal turbinates (superior, middle and inferior)

4) posterior naris (exits nasal cavity and enters nasopharynx)

What is the function of the nasal turbinates?

warm, humidify, and filter the air before it reaches the lungs

For each of the space (Inferior meatus, Middle meatus, Superior meatus, Sphenoethmoidal recess), what structures drain into each?

Inferior meatus = nasolacrimal duct

Middle meatus = frontal, maxillary, and anterior/middle ethmoid sinuses

Superior meatus = posterior ethmoid sinus

Sphenoethmoidal recess = sphenoid sinus

What are the major arteries of the nasal cavity (as discussed in class)?

terminal branches of maxillary and facial arteries

anterior and posterior ethmoidal arteries

Kiesselbach’s area = anatomosis, common site of nosebleeds

What is the general innervation of the nasal cavity (as discussed in class)?

olfactory nerve (CN I) = special sensation (smell)

ophthalmic nerve (V1) and maxillary nerve (V2) = general sensation

What major openings are found within the orbit? What structures pass through these openings?

optic canal = CN II, ophthalmic artery

superior orbital fissure = CN III, IV, frontal nerve (branch of V1), VI, superior ophthalmic vein

inferior orbital fissure = inferior ophthalmic vein

What are the components of the lacrimal apparatus?

Lacrimal gland

Lacrimal ducts

Lacrimal (serous) fluid

Lacrimal canaliculi - puncta

Lacrimal sac

Nasolacrimal duct

Where is the lacrimal gland located? What muscle divides it into two parts?

anterior, superotemporal part of orbit

divided by the levator palpebrae superioris

Trace the pathway of tear formation from the gland that produces tears to the nasal meatus that tears drain into.

lacrimal gland - lacrimal ducts - lacrimal fluid exits and blinking distributes fluid across the eye - fluid enters thru puncta into lacrimal canaliculi - lacrimal sac - nasolacrimal duct - drains inferior nasal meatus

What is the common tendinous ring?

fibrous ring in the back of orbit

origin for 4 rectus muscles of eye (superior, inferior, medial and lateral rectus)

List the extraocular muscles?

superior oblique, inferior oblique, superior rectus, inferior rectus, medial rectus, lateral rectus

What are the movements of the eyeball?

elevation (up), depression (down), adduction (to nose), abduction (away from nose)

List their attachments, their function, and innervation: Superior Rectus

common tendinous ring

elevation, adduction

oculomotor nerve

List their attachments, their function, and innervation: Inferior Rectus

common tendinous ring

depression, adduction

oculomotor nerve

List their attachments, their function, and innervation: Medial Rectus

common tendinous ring

adduction

oculomotor nerve

List their attachments, their function, and innervation: Lateral Rectus

common tendinous ring

abduction

abducens nerve

List their attachments, their function, and innervation: Superior Oblique

body of sphenoid bone

depression, abduction

trochlear nerve

List their attachments, their function, and innervation: Inferior Oblique

floor of orbit

elevation, abduction

oculomotor nerve

Describe the autonomic innervation of the eye.

Ciliary ganglion:

Parasympathetic = pregangionic fibers branch of CN III, posterganglionic fibers travel in short ciliary nerve, innervates sphincter pupillae muscle (pupil constriction) and ciliary muscle (control shape of lens)

Sympathetic = has various paths, innervates dilator pupillae muscle (pupil dilation)