Head and Neck Flashcards
Compartments and Fascias of the Neck
- somatic neck (perivertebral fascia)
- visceral neck (peritracheal fascia)
- vascular compartment (carotid sheath)
- investing fascia
- retropharyngeal space

Retropharyngeal Space
Cervical Vertebrae
- C1-7
- C1 = atlas
- C2 = axis
- C7 = vertebra prominens
Atlanto-occipital joint
“yes” joint between atlas and occipital bone
Atlantoaxial joint
- “no” joint between atlas and axis
- contributes to 50% of rotation of neck

Hyoid bone
- greater horn
- lesser horn
Superficial Neck Muscles w/ Innervation
- sternocleidomastoid
- trapezius
- largest muscles moving the head
- CN XI - spinal accessory
Sternocleidomastoid
- O: manubrium of sternum, medial clavicle
- I: mastoid process
- A:
- unilateral - rotation of head to opposite side, flexion to same side
- bilateral - flexion of neck
- I:
- motor: spinal accessory (IX)
- general sensory: cervical plexus (C2-3)
- A: occipital artery, superior thryoid artery
Middle Neck Muscles w/Innervation
- suprahyoid muscles
- infrahyoid muscles
- inside anterior triangle
- innervated by ventral primary rami of cervical spinal nerves
Suprahyoid muscles
- above hyoid bone
- move hyoid and jaw
Infrahyoid Muscles
- below hyoid bone
- move hyoid and larynx
- thyrohyoid, sternothyroid, omohyoid, sternohyoid
Deep Layer of Neck Muscles
- muscles deep to the perivertebral fascia including scalenes
- longus capitis
- longus colli
- scalenes (anterior, middle, posterior)
Visceral Structures of the Neck
- endocrine - thyroid, parathyroid
- respiratory - larynx, trachea
- alimentary - pharynx, esophagus
Directions for Blood Vessels
- arteries run up from thorax to head
- veins run down from head to thorax
Major Arteries of the Neck
- subclavian artery
- vertebral artery
- thyrocervical trunk
- common carotid artery
- internal carotid
- external carotid
Branches of the Thyrocervical Trunk
- comes off first part of subclavian medial to anterior scalene
- TITS
- inferior thyroid artery
- transverse cervical artery
- suprascapular artery
Major Veins of the Neck
- subclavian vein
- internal jugular vein - brain, neck
- external jugular vein - scalp, side of face
- venous angle
- brachiocephalic vein
- anterior jugular
Nerves of the Neck (Major Categories)
- cranial nerves (down from head)
- sympathetic nerves (up from thorax)
- cervical spinal nerves (some intrinsic)
Cranial Nerves of the Neck
- vagus (X)
- jugular foramen
- major parasympathetic of thorax and abdomen
- motor and sensory to pharynx and larynx
- accessory nerve (XI)
- jugular foramen
- motor SCM and trapezius
- hypoglossal nerve (XII)
- hypoglossal canal
- motor to muscles of the tongue
Contents of Carotid Sheath
- carotid arteries (common and internal)
- internal jugular vein
- vagus nerve
Sympathetic Nerves of the Neck
- cervical sympathetic trunk
- superior cervical ganglion
Cervical Spinal Nerves
- cervical plexus (C1-4)
- brachial plexus (C5-T1)
Root of the Neck Boundaries
- first ribs
- manubrium of sternum
- T1 vertebrae
Structures in Root of the Neck (for head and neck)
- bone: cervical vertebrae
- muscle: prevertebral muscles, scalenes, infrahyoid muscles
- visceral: trachea, esophagus
- vessels: vertebral artery, common carotid, inferior thyroid artery, jugular veins (internal, external, anterior)
- nerves: phrenic nerve, vagus nerve, recurrent laryngeal, sympathetic trunk
Phrenic Nerve
- C3, 4, 5, keep the diaphragm alive
- anterior aspect of anterior scalene
Boundaries of Posterior Triangle
- sternocleidomastoid
- trapezius
- clavicle
Posterior Triangle Roof
investing fascia
Posterior Triangle Floor
- from superior to inferior
- splenius capitis major
- levator scapulae
- scalenes
- perivertebral fascia
Subdivisions of Posterior Triangle
- inferior belly of omohyoid (occipital triangle above, omoclavicular triangle triangle)
- spinal accessory nerve (carefree zone above, careful zone below)

- SCM
- levator scapulae
- clavicle
- trapezius
- lesser occipital nerve
- great auricular nerve
- transverse cervical nerve
- external jugular vein
Nerves in Posterior Triangle

- spinal accesory (XI)
- cervical plexus (C1-4)
- sensory branches: coming from nerve point
- lesser occipital nerve - scalp
- great auricular nerve - around ear
- transverse cervical nerve - anterior triangle
- supraclavicular nerves - posterior triangle
- if nerve point is anesthetized, skin of neck is numb
- contributes to ansa cervicalis
- motor branches: phrenic nerve
- sensory branches: coming from nerve point
- brachial plexus
- dorsal scapular nerve
Veins in Posterior Triangle
- external jugular
Arteries in Posterior Triangle

- transverse cervical artery - superficial back muscles
- suprascapular artery - shoulder
- dorsal scapular artery
Topographical Landmarks of Posterior Triangle
- SCM - separates anterior and posterior triangle
- thyroid cartilage
- mandible
Platysma
- O: subcutaneous tissue around clavicle
- I: mandible, cheek, lip, mouth
- A: expressions of sadness and fright
- I: cervical branch of facial nerve (VII)
- A: submental artery, suprascapular artery
Boundaries of Anterior Triangle
- SCM
- inferior border of mandible
- midline of the neck
Subdivisions of Anterior Triangle

A. submental triangle
B. submandibular triangle
C. carotid triangle
D. muscular triangle
Submandibular Triangle Boundaries
- inferior border of mandible
- anterior belly of digastric
- posterior belly of digastric
Submandibular Triangle Contents
- submandibular salivary gland
- hypoglossal nerve
- mylohyoid nerve
Submental Triangle Boundaries
- midline of neck
- anterior digastric
- hyoid bone
Submental Triangle Contents
- mylohyoid muscles
Carotid Triangle Boundaries
- posterior belly of digastric
- superior omohyoid
- SCM
Carotid Triangle Contents
- common carotid artery and its bifurcation into internal and external carotid arteries
- carotid body and sinus (IX and X)
- glossopharyngeal (IX)
- vagus (X)
Muscular Triangle Boundaries
- midline of neck
- superior belly of omohyoid
- SCM
Muscular Triangle Contents
- 4 infrahyoid/strap muscles - depress and stabilize the hyoid
- sternohyoid
- sternothyroid
- thyrohyoid
- omohyoid
Suprahyoid Muscles
- 5 muscles
- anterior belly of digastric
- posterior belly of digastric
- stylohyoid
- mylohyoid
- geniohyoid
- A:
- if infrahyoids are active, then depress mandible (except stylohyoid)
- if infrahyoids are inactive, then elevate hyoid/neck
- I:
- mylohyoid nerve (V3): anterior digastric, mylohyoid
- facial (VII): posterior digastric, stylohyoid
- C1: geniohyoid
Anterior Belly of Digastric
- O: digastric fossa of mandible
- I: intermediate tendon
- A: depress mandible, elevate hyoid
- I: mylohyoid nerve (V3)
- A: facial artery
Posterior Belly of Digastric
- O: mastoid process
- I: intermediate tendon
- A: depress mandible, elevate hyoid
- I: facial (VII)
- A: occipital artery
Stylohyoid
- O: styloid process
- I: hyoid bone
- A: elevate hyoid
- I: facial (VII)
- A: N/A
Mylohyoid
- O: mylohyoid line of mandible
- I: hyoid
- A: depress mandible, elevate hyoid
- I: mylohyoid nerve (V3)
- A: mylohyoid branch of inferior alveolar artery
Geniohyoid
- O: mental spine of mandible
- I: hyoid
- A: depress mandible, elevate hyoid
- I: C1 via hypoglossal (XII)
- A: N/A
Infrahyoid Muscles
- 4 strap muscles
- omohyoid
- sternohyoid
- sternothyroid
- thyrohyoid
- action: stabilize hyoid bone when active, allow hyoid to move when relaxed
- innervation:
- ansa cervicalis (C1-3) for omohyoid, sternohyoid, and sternothyroid
- C1 via hypoglossal (XII) for thyrohyoid
Omohyoid
- O: superior border of scapula
- I: hyoid
- A: stabilize hyoid, allow hyoid movement
- I: ansa cervicalis
Sternohyoid
- O: sternum
- I: hyoid
- A: stabilize hyoid, allow for hyoid movement
- I: ansa cervicalis
- A: superior thyroid artery
Sternothyroid
- O: sternum
- I: thyroid cartilage
- A: stabilize hyoid, allow for hyoid movement
- I: ansa cervicalis
- A: superior thyroid artery
Thyrohyoid
- O: thyroid cartilage
- I: hyoid
- A: stabilize hyoid, allow for hyoid movement
- I: C1 via hypoglossal (XII)
- A: superior thyroid artery
Common Carotid Artery Asymmetry
- right - from brachiocephalic artery
- left - from aortic arch
Carotid Body and Sinus w/Innervations
- located at bifurcation of common carotid artery
- carotid body - chemoreceptors
- carotid sinus - baroreceptors
- afferent - glossopharyngeal (IX)
- efferent - vagus (X)
- parasympathetic - decreased heart rate and contractility
- sympathetic - increased heart rate and contractility
External Carotid Branches
- “Some Angry Lady Figured Out PMS”
- superior thyroid artery - thyroid, strap muscles
- ascending pharyngeal artery - soft palate
- lingual artery - tongue
- facial artery - face
- occipital artery - occiput area
- posterior auricular artery - behind external ear
- maxillary artery - infratemporal fossa, deep face
- superior temporal artery - side of head
Internal Jugular Vein System
- drains sigmoid sinus in neurocranium
- facial vein and retromandibular vein contributes
Vagus Nerve (X)
- jugular foramen –> carotid sheath –> thorax
- branches:
- pharyngeal plexus - palate and pharynx
- superior laryngeal nerve
- internal laryngeal nerve - sensory to area above glottis, pierces thyrohyoid membrane
- external largyneal nerve - motor to cricothyroid and inferior pharyngeal constrictor
- recurrent laryngeal nerve - larynx, posterior cricoarytenoid, lateral cricoarytenoid, arytenoideus, thyroarytenoid, aryepiglottis, esophagus
Head and Neck Sympathetics
- preganglionic
- T1-4
- sympathetic chain
- 3 ganglions - stellate, middle, superior cervical
- postganglionic - hitch rides with cervical spinal nerves and arteries
Thyroid Gland
- highly vascularized
- superior thyroid artery from above (branch of external carotid)
- inferior thyroid artery from below (branch of subclavian artery)
Head and Neck Lymphatics
- many lymph nodes under SCM
- deep cervical chain

- common carotid artery
- external carotid artery
- internal carotid artery
- lingual artery
- facial artery
- continuation of external carotid
- ascending pharyngeal artery
- occipital artery
- superior thyroid
- superior laryngeal artery
- cervical sympathetic trunk
- internal laryngeal nerve
- hypoglossal nerve
Neurocranium
houses brain and special senses
Viscerocranium
“gut” cranium - feeding, eating, speaking, etc.
Viscerocranium Subdivisions
- orbital region
- nasal region
- upper jaw
- lower jaw
- infratemporal and temporal fossa
Cutaneous Nerve Supply
Arterial Blood Supply to Head
- neurocranium: vertebral artery (posterior cranial fossa), internal carotid (anterior and middle cranial fossa)
- viscerocranium: external carotid
Venous Drainage from the Head
- neurocranium: sinuses
- internal jugular vein
- no valves!
Cranial Nerve Modalities
- sensory/afferent
- general sensory - pain, temperature, touch, propioception, pressure, etc.
- special sensory - smell, vision, hearing, balance, taste
- visceral sensory - pain from viscera, blood pressure, oxygen content
- motor/efferent
- somatic/branchial motor - skeletal muscle
- visceral motor - smooth muscle (cranial nerves only have parasympathetic)
Olfactory Nerve (I)
- modality: special sensory (olfaction)
- foramen: cribiform plate
- course: fila olfactoria –> olfactory bulb –> olfactory tract
- innervated structure: olfactory organ
Optic Nerve (II)
- modality: special sensory (vision)
- foramen: optic canal
- course: within orbit –> optic canal –> optic chiasm
- innervated structure: retina
Oculomotor Nerve (III)
- modality: somatic motor, visceral motor
- foramen: superior orbital fissure
- innervated structure:
- somatic motor: 4 EOMs (superior, medial, and inferior recti, inferior oblique), levator palpebrae superioris
- visceral motor: sphincter pupillae, ciliary muscles (ciliary ganglion)
- course: within orbit, splits into superior and inferior divisions
Trochlear Nerve (IV)
- modality: somatic motor
- foramen: superior orbital fissure
- innervated structure: superior oblique
- course: within orbit
Trigeminal Nerve (V)
- 1st pharyngeal arch
- 3 branches:
- opthalamic (V1)
- maxillary (V2)
- mandibular (V3)
- modality: all general sensory, V3 also has branchial motor
- V3 branch guides parasympathetics and taste fibers from facial nerve to anterior 2/3 of tongue
Opthalamic Nerve (V1)
- modality: general sensory
- foramen: superior orbital fissure
- course: branching within orbit (NFL)
- nasociliary nerve (nasal cavity mucosa)
- frontal - supratrochlear, supraorbital (forehead skin, mucosa of frontal sinus, upper eyelid skin
- lacrimal nerve (lacrimal gland)
Maxillary Nerve (V2)
- modality: general sensory
- foramen: foramen rotundum
- innervated structures: skin of lateral nose, inferior eyelid, cheek, and upper lip, maxillary teeth, mucous membranes of nasal cavity, paranasal sinuses, palate, and oral vestible
- course: to pterygopalatine fossa –> branches
- infraorbital nerve (infraorbital canal)
- zygomatic nerve (inferior orbital fissure)
- nasopalatine (sphenopalatine foramen)
- superior alveolar nerves
- palatine nerves
- pharyngeal nerves
Mandibular Nerve (V3)
- modality: general sensory, somatic motor
- foramen: foramen ovale
- course: infratemporal fossa, branching
- sensory branches (BAIL) - skin of lower lip, buccal, parotid, and temporal regions of face, mandibular teeth, TMJ, mucosa of oral cavity
- long buccal
- auriculotemporal
- inferior alveolar
- lingual
- motor branches - muscles of mastication, mylohyoid, anterior digastric, tensor veli palatini, tensor tympani
- sensory branches (BAIL) - skin of lower lip, buccal, parotid, and temporal regions of face, mandibular teeth, TMJ, mucosa of oral cavity
Abducens (VI)
- modality: somatic motor
- foramen: superior orbital fissure
- innervated structure: lateral rectus
- course: within orbit laterally
Facial Nerve (VII)
- 2nd pharyngeal arch
- 4 modalities: general sensory, special sensory (taste), somatic/branchial motor, visceral motor
- foramen: internal acoustic meatus
- branches:
- greater petrosal nerve (parasympathetics)
- nerve to stapedius (somatic motor)
- chorda tympani (special sensory, parasympathetics, visceral motor
- auricular (general sensory)
- other branches - facial expression, stylohyoid, posterior belly of digastric (somatic motor)
- innervated structures:
- branchial motor - muscles of facial expression, posterior belly of digastric, stylohyoid, stapedius
- visceral motor - lacrimal gland via pterygopalatine ganglion, submandibular and sublingual glands via submanidbular ganglion
- general sensory - area of skin on auricle
- taste - anterior 2/3 of tongue
Vestibulocochlear Nerve (VIII)
- modality: special sensory (hearing, balance)
- foramen: internal acoustic meatus (doesn’t exit skull)
- branches:
- vestibular nerve (utricle, saccule of inner ear)
- cochlear nerve (hair cells, semicircular ducts)
Glossopharyngeal Nerve (IX)
- 3rd pharyngeal arch
- 5 modalities: general sensory, special sensory (taste), visceral sensory, branchial/somatic motor, visceral motor
- foramen: jugular foramen
- branches
- tympanic nerve (general sensory, parasympathetics)
- carotid sinus nerve
- small branchial motor nerve (stylopharyngeus)
- other branches (general sensory to mucous membrane of oropharynx, taste to posterior 1/3 of tongue)
- innervated structures
- branchial motor - stylopharyngeus
- visceral motor - parotid via tympanic nerve and otic ganglion
- general sensory - tympanic cavity, mucosa of oropharynx, posterior 1/3 of tongue
- visceral sensory - carotid sinus and body
- special sensory - posterior 1/3 of tongue
Vagus (X)
- 5 modalities: general sensory, special sensory (taste), visceral sensory, branchial motor, visceral motor
- foramen: jugular foramen
- innervated structures:
- general sensory - inferior pharyx and larynx, root of tongue and epiglottis
- special sensory - taste for root of tongue
- somatic motor - muscles of soft palate and pharynx, muscles of larynx
- visceral motor and sensory - thoracic and abdominal organs
- branches in head and neck
- pharyngeal branches - pharyngeal plexus
- superior laryngeal nerve - general sensory to mucosa of larynx up to vocal folds, motor to cricothyroid muscle
- recurrent laryngeal nerve - general sensory to mucosa of larynx inferior to vocal folds, motor to internal laryngeal muscles
Spinal Accessory (XI)
- modality: somatic motor
- foramen: jugular foramen
- course: with internal carotid
- innervated structures: SCM, trapezius
Hypoglossal Nerve (XII)
- modality: somatic motor
- foramen: hypoglossal canal
- course: forms loop in carotid triangle, C1-2 run with hypoglossal for a while, approach tongue from inferior
- innervated structures: most extrinsic and all intrinsic muscles of the tongue
Parasympathetics in the Head
- CNIII, VII, IX, X
- 4 ganglion
- ciliary ganglion (III)
- pterygopalatine ganglion (VII)
- submandibular ganlgion (VII)
- otic ganglion (IX)
Ciliary Ganglion
- pre: CN III
- post: short ciliary nerves
- innervate: ciliary muscles, sphincter pupillae
Pterygopalatine Ganglion
- pre: CN VII –> greater petrosal nerve
- post: fibers travel with V2
- innervate lacrimal gland and other small glands
Submandibular Ganglion
- pre: CN VII –> chorda tympani via lingual nerve
- post: travel with lingual nerve
- innervate: submandibular gland, sublingual gland
Otic Ganglion
- pre: CN IX –> lesser petrosal nerve (with tympanic nerve)
- post: travel with auriculotemporal nerve (V3)
- innervate: parotid gland
Mnemonics for Cranial Nerves
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