Structures in the Pharynx

Arteries

vertebral

common carotid – runs just lateral to the thyroid glands

Veins

internal jugular

Nerves

sympathetic trunk and cervical ganglia

superior – located at level of axis and altas; supplies all sympathetic innervation of the head

middle – lies on the anterior aspect of the inferior thyroid a at the level of the cricoid; postganglionic branches pass to C5 and C6 nerves, the heart, and thyroid gland

inferior – usually fused with the 1^st thoracic ganglion to form the cervicothoracic (stellate) ganglion; lies at superior border of the neck of the first rib; postganglionic fibers to C7 and C8, heart, and vertebral plexus

inferior (nodose) ganglion – ganglion in the vagus just south of the jugular foramen; connects with hypoglossal, accessory, and the superior ganglion of the sympathetic trunk

superior laryngeal – branch of the vagus just after the inferior ganglion; divides in the carotid sheath into the internal and external laryngeal nerves (internal supplies sensory to mucous membrane of larynx superior to the vocal cords; external supplies motor to the inferior constrictor and cricothyroid mm)

pharyngeal – branch of vagus from inferior ganglion; motor supply to palate and lower pharynx; sensory to lower pharynx

Bones

C1 (atlas)

posterior arch – connects lateral mass with posterior tubercle

anterior arch – connects the lateral mass with the anterior tubercle

transverse process – contains transverse foramen for vertebral aa; also lateral mass (articulation with skull)

superior articular facet – one on each side; articulates with the occipital condyle

C2 (axis)

dens (odontoid process) – blunt process that projects superiorly into vertebral foramen of atlas

attaches to atlas via the transverse ligament of the atlas

occipital

foramen magnum – largest foramen of skull; contents: medulla, meninges, vertebral aa, spinal roots of accessory nerves

condyle – one on either side of the foramen magnum; articulates with the atlas

hypoglossal canal – two, just lateral to the foramen magnum; passage of CN XII (hypoglossal)

jugular foramen – two, just lateral to the hypoglossal canal; passage of the jugular, CN IX (glossopharyngeal), CN X (vagus), CN XI (accessory), sigmoid sinus, posterior meningeal artery

sphenoid

foramen ovale – in the greater wing; admits V³, accessory meningeal a

anterior transverse line – separates the anterior and middle cranial fossae

temporal

mastoid – not present in newborns; enlarges with puberty; provides attachment of the SCM muscle

styloid process – attachment of stylohyoid, stylopharyngeous, and styloglossus mm

posterior transverse line – separates the middle and posterior cranial fossae

conchae – on the lateral wall of the nasal cavity; three longitudinal projections that project medially and inferiorly to produce three air passages: superior, middle, and inferior meatus

superior concha – part of ethmoid bone; conceals the superior meatus into which the ethmoidal sinuses open

middle concha – part of ethmoid bone; middle meatus communicates with the frontal sinus anteriorly

inferior concha – a separate bone (called inferior concha); the nasolacrimal duct opens into its anterior aspect

Bony Regions

choanae (posterior nares): two aperatures that connect the nose and the nasopharynx

nasal septum: divides the nasal cavity into two fossae

Joints

atlanto-occipital – junction of atlas and occipital bone; permits nodding of the head

Ligaments

cruciform (superior and inferior bands) – superior band runs from the transverse ligament of the atlas to the occipital bone; inferior band runs from the transverse ligament of the atlas to the body of C2

alar – from the sides of the dens to the margins of the foramen magnum

Muscles

rectus capitis lateralis – transverse process of C1 to the jugular process of the occipital bone

innervation: ventral primary rami C1-C2

action: flexes neck; holds head stabile on neck

rectus capitis anterior – lateral mass of the atlas to the base of the skull

innervation: ventral primary rami of C1-C2

action: flexes neck; holds head stabile on neck

longus capitis – anterior tubercles fo C3-C6 to the base of the skull; lateral to longus coli

innervation: ventral primary rami of C1-C3

action: flexes neck; holds head stabile on neck

longus coli – adjacent to midline; from anterior tubrercle of C1 to body of T3

innervation: ventral primary rami of C2-C7

action: flexes neck,

scalenus anterior – from transverse processes of C2-C6 to tubercle of 1^st rib

innervation: cervical plexus

action: elevates 1^st rib and flexes neck

stylopharyngeus – styloid process of temporal bone to posterior and superior borders of the thyroid cartilage

innervation: CN IX (glossopharyngeous)

action: elevates pharynx and larynx during swallowing or speaking

constrictors:

innervation: pharyngeal plexus (vagus portion)

action: constrict pharynx during swallowing

superior – from the pterygoid hamulus, ptergomandibular raphae, and mylohyoid line to the median raphae of the pharynx (posterior of pharynx) and the pharyngeal tubercle

middle – from stylohyoid ligament, hyoid bone to median raphae of pharynx

inferior – from the oblique line of thyroid cartilage and cricoid cartilage to the median raphae of the pharynx

mylohyoid – mylohyoid line of mandible to raphae and body of hyoid bone

innervation: mylohyoid nerve (branch of inferior alveolar)

action: elevates hyoid bone and floor of mouth

geniohyoid – inferior mental spine of mandible to body of hyoid bone

innervation: C1 via CN XII

action: widens pharynx by pulling hyoid anterosuperiorly

recurrent laryngeal – supplies all the intrinsic muscles of the larynx except the cricothyroid

Membranes

dura mater

tectorial (membrana tectoria) – continuation of posterior longitudinal ligament; runs from body of C1 to the internal surface of the occipital bone

anterior/posterior atlanto-occipital – from anterior and posterior arches of atlas to anterior and posterior margins of the foramen magnum

prevertebral fascia – tubular fascia that surrounds the vertebrae and vertebral mm

pharyngeal wall –five layers:

(1) areolar layer (buccopharyngeal fascia)–permits mvt. of pharynx; contains pharyngeal plexus of nerves and veins; continuous with epimysium covering buccinator and pharyngeal muscles

(2) muscular layer – outer circular, inner longitudinal

(3) fibrous layer (pharyngobasilar fascia): attached to the skull

(4) submucosa

(5) mucous membrane

Miscellaneous

retropharyngeal (retrovisceral) space – space between the prevertebral and pretrachial fascia

pharynx – passage from nasal cavity to larynx; communicates with posterior nares, eustachian tube, mouth, esophagus, larynx

nasopharynx (nasal) – superior portion, above the soft palate

oropharynx (oral) – middle portion, between soft palate and root of the epiglottis; opens to oral cavity

laryngopharynx (laryngeal) – inferior portion; between the root of the epiglottis, and the esophagus

eustachian tube – provides communication of the middle ear with the nasopharynx

torus tubarious–hood-like elevation over auditory tube where it enters the nasopharynx; formed by cartilagenous part of auditory tube

pharyngeal recess–recess in lat.wall of nasopharynx above andbehind opening of eustachian tube, posteriorto torus tubarious

pharyngeal (nasopharyngeal) tonsil (adenoid) – collection of tissue in posterior wall of nasopharynx; contacts soft palate when swallowing

palatoglossal arch – anterior pillar of the fauces, formed by the bulge of the palatoglossal muscle in the oropharynx

palatopharyngeal arch–posterior pillar of faucesmucous membrane covered bulge of the palatopharyngeal muscle in oropharynx

fauces –constricted opening from mouth to oropharynx; bounded by the arches, the base of the tongue, and the soft palate

palatine tonsil – collection of lymphoid tissue between the palatine arches; commonly referred to as "the tonsils"

piriform recess – small, pear-shaped recess lateral to the epiglottis, in the laryngopharyngeal cavity on each side of the inlet of the larynx; lateral walls are bounded by the interior of the thyroid cartilage

median glossoepiglottic fold – the mucous membrane of the epiglottis is reflected to the posterior part of the tongue as one median and two lateral glossoepiglottic folds on the anterior side of the epiglottis

vallecula – depressions in epiglottis between median and lateral glossoepiglottic folds; Latin for ditch, since saliva collects here;

2 parts: tongueoral (anterior boundry, formed by base of the tongue) and pharyngeal (posterior wall formed by epiglottis)

sulcus terminalis – lies on tongue behind the circumvallate papillae; passes through the foramen cecum

foramen cecum – lies at the boundry of the anterior 2/3 and posterior 1/3 of the tongue; remnant of opening of thyroglossal ducts

vallate papillae – form a ‘V’ that separates the anterior (oral part) and posterior (pharyngeal part) of the tongue; vallate papillae are surrounded by a trench that contains taste buds

filiform papillae – rough, hairlike papillae that aid in the licking of ice cream; very sensitive to touch

fungiform papillae – fewer in number than the filiform; mushroom shaped papillae

lingual tonsil – posterior part of the tongue is covered with lymphoid nodules collectively known as the "lingual tonsils"