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83 Cards in this Set

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Hyoid bone
The hyoid bone is a U-shaped bone superior to the thyroid cartilage and inferior to the chin. It has a body, as well as greater & lesser horns. It does not articulate with any other bones. It is anchored in place by the suprahyoid and infrahyoid muscles. Movements of the hyoid bone result in movements of the tongue and larynx.
omohyoid muscle
Proximal Attachment: The inferior belly attaches to the scapula just medial to the suprascapular notch (see green area below)
Distal Attachment: The superior belly attaches to the inferior border of the hyoid bone (see blue area below)
Innervation: Ansa cervicalis
Actions: Depression and retraction of the hyoid bone
Note that the tendon connecting the superior and inferior bellies is attached by fibrous tissue to the clavicle.
Thyroid cartilage
The thyroid cartilage (see red outline below) is the largest of the three cartilages that make up the laryngeal skeleton (along with the cricoid and epiglottic cartilages). The anterior border of the cartilage protrudes to form the laryngeal prominence (i.e. “Adam’s Apple”). It is open posteriorly. Its superior horns attach to the hyoid bone via the thyrohyoid membrane and the inferior horns articulate with the lateral surfaces of the cricoid cartilage (i.e. cricothyroid joints).
sternothyroid muscle
Proximal Attachment: Manubrium of the sternum (see green area below) Distal Attachment: Oblique line of the thyroid cartilage (see blue area below) Innervation: Ansa cervicalis
Actions: Depression of the hyoid bone and larynx
thyrohyoid muscle
Proximal Attachment: Oblique line of thyroid cartilage (see green area below) Distal Attachment: Body of the hyoid (see blue area below)
Innervation: Nerve to thyrohyoid (C1 piggybacks on hypoglossal nerve [XII])
Actions: Depression of the hyoid bone and elevation of the larynx
cricoid cartilage
The cricoid cartilage (see red outlines below) is the only laryngeal cartilage that forms a complete ring around the airway, although it is narrow anteriorly and wide posteriorly. It is attached to the inferior margin of the thyroid cartilage and to the first tracheal ring by ligaments.
Thyroid gland
The thyroid gland is located anterolateral to the larynx and trachea. It consists of right and left lobes (green arrows below), with a connecting isthmus in front of the tra- chea (green arrow below). In about 50% of people there is a small pyramidal lobe ex- tending superiorly from the isthmus (yellow arrow below). The thyroid gland’s blood supply comes from the superior and inferior thyroid arteries and it is drained by a supe- rior, middle, and inferior thyroid veins.
Tracheal Rings
The tracheal rings are C-shaped cartilaginous rings, which maintain the opening of the trachea (red arrows). They are not present posteriorly (green arrow) allowing the esophagus to to expand while swallowing without obstructing the airway.
Submandibular triangle
a) Superior: inferior border of the mandible
b) Anterior: anterior belly of the digastric muscle c) Posterior: posterior belly of the digastric muscle
submandibular gland
The submandibular gland is a U-shaped salivary gland. Its external portion fills most of the submandibular triangle while its deep portion is deep to the mylohyoid muscle.
digastric muscle
Proximal Attachment: The anterior belly attaches to the digastric fossa of the man- dible (see green area below)
Distal Attachment: The posterior belly attaches to the mastoid notch of the tempo- ral bone (see red area below)
Note: There is an intermediate tendon between the two bellies that is attached to the hyoid bone (see blue area below)
Innervation:
Anterior belly - Nerve to the mylohyoid Posterior belly - Facial n. (VII)
Actions: Depression of the mandible; elevation of the hyoid bone
mylohyoid muscle
Proximal Attachment: Mylohyoid line of the mandible (see green area on image) Distal Attachment: Body of hyoid bone (see blue area on image)
Innervation: Nerve to the mylohyoid
Actions: Elevation of the hyoid bone and tongue
stylohyoid muscle
Proximal Attachment: Styloid process of the temporal bone (see green area on im- age)
Distal Attachment: Body of the hyoid bone (see blue area on image) Innervation: Facial nerve (CN VII)
Actions: Elevation and retraction of the hyoid bone
hypoglossal nerve (XII)
Origin: Brain
Branches:
There are no named branches
Note: The superior root of the ansa cervicalis appears to branch off the hypoglos-
sal nerve but it is not part of XII and is only piggybacking
Muscles Innervated (GSE):
Intrinsic muscles of the tongue
Extrinsic muscles of the tongue (with the except the palatoglossus muscle) Genioglossus muscle
Hyoglossus muscle
Styloglossus muscle
Glands Innervated (GVE): None General Senses (GA): None Special Senses (SA): None
Path: The hypoglossal nerve leaves the skull through the hypoglossal canal (red ar- rows in images). After exiting the cranial cavity the nerve passes inferiorly, medial to the angle of the mandible and then curves anteriorly going between the mylo- hyoid and hyoglossus muscles to enter the tongue (green arrow in image).
submental triangle
a) Anterior: mandible
b) Lateral: anterior belly of the digastric
c) Inferior: hyoid bone
d) Medial: midline of the neck
carotid triangle
a) Superior: posterior belly of digastric
b) Infero-medial: superior belly of the omohyoid
c) Lateral: anterior border of the sternocleidomastoid
ansa cervicalis
Muscles Innervated:
Geniohyoid Sternohyoid Sternothyroid Thyrohyoid Omohyoid
Skin Innervated: None
Path:
Inferior root of ansa cervicalis (red arrow) – Formed from spinal nerves C2 and
C3. It runs on the anterior surface of the internal jugular vein and forms a
loop by joining the superior root of the ansa cervicalis.
Superior root of ansa cervicalis (green arrow) – Formed from spinal nerve C1. It
piggybacks for a short distance on the hypoglossal nerve (XII; blue arrow) af- ter which it descends on the anterior surface of the carotid arteries.
thyrohyoid membrane
The thyrohyoid membrane is a fibro-elastic layer of tissue attached to the hyoid bone and the thyroid cartilage. It facilitates the upward movement of the larynx dur- ing swallowing and is the site of entrance of the internal laryngeal nerve and the supe- rior laryngeal vessels.
internal branch of the superior laryngeal nerve
Origin: The internal laryngeal nerve (green arrow below) is one of the two terminal branches of the superior laryngeal nerve (red arrow below; the other being the ex- ternal laryngeal nerve [blue arrow below)
Muscles Innervated: None
Glands Innervated (GVE): Mucosal glands of the larynx superior to the vocal folds General Senses (GA): Mucosal surface of the larynx superior to the vocal folds Special Senses (SA): Taste from the epiglottis and base of the tongue
Path: The internal laryngeal nerve descends through the carotid triangle of the neck piercing the thyrohyoid membrane to enter the larynx it is accompanies by the su- perior laryngeal artery
superior laryngeal nerve
Origin: The superior laryngeal nerve (green arrow below) is a branch of the vagus nerve (X; red arrow)
Branches:
Internal laryngeal nerve External laryngeal nerve
Path: The superior laryngeal nerve descends posterior to the internal carotid artery. In the carotid triangle of the neck it bifurcates into the internal and external laryn- geal nerves.
external laryngeal nerve
Origin: The external laryngeal nerve (green arrow below) is one of the two terminal branches of the superior laryngeal nerve (red arrow below; the other being the in- ternal laryngeal nerve [blue arrow below)
Muscle Innervated (SVE): Cricothyroid muscle
Glands Innervated (GVE): Mucosal glands of the larynx superior to the vocal folds
General Senses (GA): Proprioception from the cricothyroid muscle
Special Senses (SA): Taste from the epiglottis and base of the tongue
Path: The external laryngeal nerve descends through the carotid triangle of the neck adjacent to the superior thyroid artery, to reach the cricothyroid muscle
cricothyroid muscle
Proximal Attachment: Anterolateral part of cricoid cartilage (see green area below) Distal Attachment: Inferior margin of the thyroid cartilage (see red area below) Innervation: External laryngeal nerve
Action: Stretching of the vocal ligament
common carotid artery
Source:
Right Common Carotid (green arrow below) – A branch the brachiocephalic trunk (red arrow below)
Left Common Carotid (blue arrow below) – A branch of the arch of the aorta
Course: Both left and right common carotid arteries ascend from the superior medi- astinum into the neck through the superior thoracic aperture. Within the neck they are enclosed by the carotid sheath along with the internal jugular vein and vagus nerve (X). The common carotid artery terminates by bifurcating into the in- ternal and external carotid arteries at the level of the superior border of the thyroid cartilage.
Branches:
Internal carotid artery External carotid artery
internal jugular vein
Source: The internal jugular vein (green arrows below) is a direct continuation of the sigmoid sinus at the jugular foramen in the posterior cranial fossa
Course: The internal jugular vein runs inferiorly through the neck within the carotid sheath along with the carotid arteries and vagus nerve (CN X). The vein leaves the anterior cervical region by passing deep to the sternocleidomastoid. The internal jugular vein joins with the subclavian vein to form the brachiocephalic vein.
Vagus Nerve (X)
Origin: The medulla of the brainstem
Muscles Innervated (SVE):
Pharyngeal muscles (except the stylopharyngeus muscle) Palatal muscles (except the tensor veli palatini)
Intrinsic muscles of the larynx
Upper esophagus
Glands Innervated (GVE): Pharyngeal glands
Mucosal glands of the larynx
General Senses (GA):
Skin of part of the ear, external auditory meatus & outer tympanic membrane Mucosal surface of the larynx
Carotid body & sinus
Proprioception to the muscles above
Special Senses (SA): Taste from the epiglottis and base of the tongue
Branches:
Cranial:

Meningeal branch to dura mater
 Auricular branch
Cervical:

Pharyngeal branches to pharyngeal plexus
 Cervical cardiac branches

Superior laryngeal nerve

Right recurrent laryngeal nerve
Thoracic and abdominal branches will be described in Block 3

Path within the Head & Neck: The vagus nerves arise bilaterally from the medulla of the brain, exit the cranium via the jugular foramina and descend through the neck within the carotid sheath between the common carotid arteries and internal jugular veins. The nerves enter the superior mediastinum posterior to the sterno- clavicular joints and brachiocephalic veins.
internal carotid artery
Source: One of two branches of the common carotid artery (the other branch being the external carotid artery)
Course:
Cervical part (green arrow below) - The internal carotid ascends in the carotid
triangle of the anterior neck enclosed by the carotid sheath along with the inter- nal jugular vein and vagus nerve (X). The cervical part has no branches. It en- ters the skull by passing into the carotid canals in the petrous portion of the temporal bone.
Petrous part (yellow arrow below) - The internal carotid artery runs within the carotid canal entering the middle cranial fossa superior to the foramen lace- rum. The petrous part has no branches.
Cavernous part (dark blue arrow below) - The internal carotid artery runs through the cavernous sinus in the lateral side of the sphenoid bone. The cav- ernous part has no branches.
Cerebral part (red arrow below) - The internal carotid artery makes a 180-degree turn where it gives off the ophthalmic branch and then joins the cerebral arte- rial circle (Circle of Willis).
Branches:
Ophthalmic (not seen in image below) Anterior cerebral (light blue arrow below) Middle cerebral (black arrow below)
external carotid artery
Source: The external carotid artery (green arrow below) is one of two branches of the common carotid artery (the other branch being the internal carotid artery)
Course: The external carotid ascends in the carotid triangle of the anterior neck en- closed by the carotid sheath along with the internal jugular vein and vagus nerve (X). It ends by bifurcating into the maxillary and superficial temporal arteries ap- proximately at the level of the ear lobe.
Branches:
Ascending pharyngeal (not seen in image below) Superior thyroid (red arrow below)
Lingual (dark blue arrow below)
Facial (yellow arrow below)
Occipital (white arrow below)
Posterior auricular (light blue arrow below) Maxillary (black arrow below)
Superficial temporal (orange arrow below)
carotid sinus
The carotid sinus is a slight dilation of the proximal part of the internal carotid ar- tery. It is a baroreceptor that responds to alterations in arterial blood pressure.
Ascending pharyngeal artery
Source: The ascending pharyngeal artery (green arrows below) is a medial branch of the external carotid artery (red arrow below)
Course: It runs in the retropharyngeal space supplying the posterior wall of the phar- ynx as well as the prevertebral muscles
Superior thyroid artery
Source: The superior thyroid artery (green artery below) is an anterior branch of the external carotid artery
Course: It runs deep to the infrahyoid muscles to reach the thyroid gland Branches:
Superior laryngeal artery (red arrow below)
Superior laryngeal artery
Source: The superior laryngeal artery (green arrow below) is a branch of the superior thyroid artery (red arrow below)
Course: It runs anteriorly and pierces the thyrohyoid membrane to reach the interior of the larynx; it is accompanied by the internal laryngeal nerve
Lingual artery
Origin: The lingual artery (green arrows below) is an anterior branch of the external carotid artery (red arrows below)
Course: The lingual artery runs on the external surface of the middle constrictor mus- cle of the pharynx, after which it passes deep to the hypoglossal nerve (XII), the sty- lohyoid, the posterior belly of the digastric muscle and hyoglossus muscles in order to reach the tongue.
Occipital artery
Origin: The occipital artery (green arrow below) is an posterior branch of the external carotid artery (red arrow below) usually at the same level as the facial artery
Course: Passes deep to the posterior belly of digastric as it travels posteriorly
Facial artery
Source: The facial artery (green arrows below) is an anterior branch of the external carotid artery (red arrow below)
Course: The facial artery travels within the submandibular gland after which it crosses the inferior border of the mandible and runs on the face. It terminates as the angular artery.
Branches:
Submental (dark blue arrow below) Inferior labial (yellow arrow below) Superior labial (light blue arrow below) Lateral nasal (brown arrow below) Angular (black arrow below)
Posterior auricular artery
Source: The posterior auricular artery (green arrow below) is a posterior branch of the external carotid artery (red arrow below)
Course: It ascends remaining superficial and runs posterior to the external ear Head and Neck
superior thyroid vein
Source: The superior thyroid vein (green arrow below) is usually formed by multiple small veins draining the superior parts of the thyroid gland
Course: The vein travels laterally and superiorly to drain into the internal jugular vein (red arrow below)
middle thyroid vein
Source: The middle thyroid vein (green arrow below) is usually formed by multiple small veins draining the inferior parts of the thyroid gland
Course: The vein travels laterally and drains into the internal jugular vein (red arrow below)
inferior thyroid vein
Source: The inferior thyroid vein (green arrow below) is usually formed by multiple small veins draining the inferior parts of the thyroid gland
Course: The vein travels inferiorly and drains into the brachiocephalic vein (red ar- rows below)
right recurrent laryngeal nerve
Origin: The right recurrent laryngeal nerve (green arrows below) is a branch of the vagus nerve (X; red arrow)
Muscles Innervated (SVE):
All intrinsic muscles of the larynx except the cricothyroid muscle Upper esophagus
Glands Innervated (GVE): Mucosal glands of the larynx inferior to the vocal folds
Mucosa Innervated (GA):
Mucosal surface of the larynx inferior to the vocal folds Proprioception to the muscles above
Special Senses (SA): None
Path: The right recurrent laryngeal nerve is a branch of the right vagus nerve in the root of the neck where it loops around the subclavian artery (blue arrow below) and ascends within a groove between the trachea and esophagus to reach the lar- ynx. It enters the larynx by passing deep to the inferior border of the inferior con- strictor muscle after which it is called the inferior laryngeal nerve.
left recurrent laryngeal nerve
Origin: The left recurrent laryngeal nerve (green arrows below) is a branch of the vagus nerve (X; red arrow)
Muscles Innervated (SVE):
All intrinsic muscles of the larynx except the cricothyroid muscle Upper esophagus
Glands Innervated (GVE): Mucosal glands of the larynx inferior to the vocal folds
Mucosa Innervated (GA):
Mucosal surface of the larynx inferior to the vocal folds Proprioception to the muscles above
Special Senses (SA): None
Path: The left recurrent laryngeal nerve is a branch of the left vagus nerve in the supe- rior mediastinum where it loops around the aortic arch and ascends within a groove between the trachea and esophagus to reach the larynx. It enters the larynx by passing deep to the inferior border of the inferior constrictor muscle after which it is called the inferior laryngeal nerve.
brachiocephalic vein
Source: The brachiocephalic veins (green arrows) are formed by the combination of the subclavian (red arrow) and internal jugular (yellow arrow) veins
Course: The right and left brachiocephalic veins unite to form the superior vena cava (blue arrow below). The left brachiocephalic vein is considerably longer than the right brachiocephalic vein because it must cross the midline before merging with the right brachiocephalic vein to form the superior vena cava.
subclavian artery
Source:
Right subclavian artery – A branch of the brachiocephalic trunk Left Subclavian artery – A branch of the arch of the aorta
Course: The subclavian artery (green arrows below) is initially lateral to the trachea after which it passes between the middle and anterior scalene muscles along with the roots of the brachial plexus. The subclavian artery changes its name to the axil- lary artery after crossing the lateral border of the first rib.
Branches:
Vertebral (red arrow below)
Internal thoracic (not seen in images below) Thyrocervical trunk (yellow arrow below) Costocervical trunk (blue arrow below)
vertebral artery
Source: The vertebral artery (green arrows below) is a branch of the subclavian artery (blue arrow below)
Course: It ascends into the root of the neck passing deep to the scalene muscles. It runs through the foramina of the transverse processes of the cervical vertebrae and enters the cranium through the foramen magnum. Here, the left and right verte- bral arteries unite as a tributary to form the basilar artery (red arrow below)
Internal thoracic artery
Source: The internal thoracic artery (green arrows below) is an inferior branch of the subclavian artery
Course: It descends into the thorax just lateral to the sternum and posterior to the ribs
Branches: It gives off anterior intercostal arteries (red arrows below) within each in- tercostal space
Note: This artery is commonly called the internal mammary artery by surgeons
thyrocervical trunk
Source: The thyrocervical (green arrow) is a branch of the subclavian artery
Course: It is located medial to the anterior scalene muscle and is usually very short be- cause it gives off branches almost immediately
Branches:
Inferior thyroid (red arrow below) Suprascapular (blue arrow below) Dorsal scapular (not seen in image) Transverse cervical (yellow arrow below)
Transverse cervical artery
Source: The transverse cervical artery (see green arrow below) is a branch of the thy- rocervical trunk (see red arrow below) but may also arise directly from the subclav- ian artery
Course: Runs through the posterior triangle of the neck anterior to the anterior sca- lene muscle to reach the deep surface of the trapezius muscle along with the spinal accessory nerve (XI). The transverse cervical artery may give rise to the dorsal scapular artery
inferior thyroid artery
Source: The inferior thyroid artery (green arrow below) is usually a branch of the thy- rocervical trunk (yellow arrow below)
Course: It travels superiorly to the thyroid gland and supplies the larynx, trachea and esophagus, as well as the thyroid gland
Branches:
Ascending cervical artery (red arrow below)
suprascapular artery
Source: The suprascapular artery (green arrow below) is usually a branch of the thyro- cervical trunk (red arrow below) but may also arise directly from the subclavian ar- tery
Course: Travels through the posterior triangle of the neck anterior to the anterior sca- lene muscle after which it runs with the suprascapular nerve toward the scapula. The suprascapular artery passes superior to the superior transverse scapular liga- ment (black arrow below) to reach the supraspinous fossa and then lateral to the spine of the scapula to reach the infraspinous fossa (blue arrow below)
ascending cervical artery
Source: The ascending cervical artery (green arrow below) is usually a branch of the inferior thyroid artery (red arrow below)
Course: It runs superiorly and posteriorly along the prevertebral muscles of the neck
thyroid ima artery
bleeding during emergency trachea procedures.

it feeds the isthmus of the thyroid and is only present in ~50% of the population
costocervical trunk
Source: The costocervical trunk (green arrow below) is a branch of the subclavian ar- tery
Course: This trunk is usually very short and bifurcates almost immediately
Branches:
Superior intercostal artery (red arrow below) Deep cervical artery (blue arrow below)
deep cervical artery
Source: The deep cervical artery (green arrow below) is usually a branch of the costo- cervical trunk (red arrow below)
Course: It goes superiorly and supplies the posterior muscles of the neck
supreme intercostal artery
Source: The supreme intercostal artery (green arrow below) is a branch of the costo- cervical trunk (red arrow below)
Course: It branches off the costocervical trunk and travels inferiorly to where it branches into the posterior intercostal arteries of the first and second intercostal spaces.
Branches: Posterior intercostal arteries (intercostal spaces 1 and 2; blue arrow be- low)
dorsal scapular artery
Source: Usually a branch of the thyrocervical trunk but may also arise directly from the transverse cervical artery
Course: Runs through the posterior triangle of the neck to run on the deep surface of the levator scapulae and rhomboid muscles; the artery is accompanied by the dor- sal scapular nerve
phrenic nerve
Origin: The phrenic nerve is formed by branches of the ventral rami of C3, 4 & 5
Muscle Innervated: Diaphragm
Skin Innervated: None
Path: Passes from the neck to the thorax by running inferiorly on the anterior scalene muscle
parotid gland
The largest of the three paired salivary glands. Located antero-inferior to the external acoustic meatus, the gland is wedged between the ramus of the mandible and the mas- toid process.
Innervation: 

Sensory: Great auricular nerve (C2 and C3) and auriculotemporal nerve (a branch of the trigeminal nerve, CN V3)
Parasympathetic: Parasympathetic component of glossopharyngeal nerve (CN IX) supplies secretory fibers. Postsynaptic fibers travel with auriculotemporal nerve
Sympathetic: Derived from cervical ganglia traveling with the external carotid nerve plexus on the external carotid artery
Action: Stimulation of the parasympathetic fibers produces a thin watery saliva
masseter muscle
Proximal Attachments: Quadrate muscle attaching to inferior border and medial surface of maxillary process of zygomatic bone and the zygomatic arch (see green area on image)
Distal Attachments: Angle and lateral surface of the ramus of the mandible (see blue area on image)
Innervation: Masseteric nerve (anterior trunk of mandibular nerve, V3) Action: Elevates mandible; superficial fibers make limited contribution to protrusion
of mandible
parotid duct
Vessel for salivary secretions from parotid gland. The duct passes horizontally from the anterior edge of the parotid gland. At the gland’s anterior edge, the duct pierces the buccinator muscle and enters the oral cavity through a small orifice opposite the sec- ond maxillary molar tooth.
buccal fat pad
An accumulation of encapsulated fat superficial to the buccinator muscle and pa- rotid duct
buccinator muscle
Proximal Attachments: Mandible, alveolar processes of maxilla and mandible,
pterygomandibular raphe (see green area on image)
Distal Attachments: Angle of mouth (modiolus) and the orbicularis oris muscle
(see blue area on image)
Innervation: Buccal branch of facial nerve (CN VII)
Actions: Presses cheek against malar teeth; works with tongue to keep food between
occlusal surfaces and out of the oral vestibule; resists distension (when blowing)
buccal branches of the facial nerve (VII)
Origin: A branch of the facial nerve proper
Muscles Innervated: Buccinator, levator labii superioris, levator anguli oris, orbicularis oris, zygomaticus major and zygomaticus minor muscles (muscles of facial expression)
Skin Innervated: None
Path: Emerges from the parotid plexus and supplies muscles of facial expression in
the buccal region
Temporal branch of the Facial nerve
Origin: A branch of the facial nerve proper
Muscle Innervated: Frontal belly of occipitofrontalis muscle (a muscle of facial expression)
Skin Innervated: None
Path: Emerges from the parotid plexus and supplies muscles of facial expression in
the temporal region
Zygomatic branch of the Facial nerve
Origin: A branch of the facial nerve proper
Muscle Innervated: Frontal belly of occipitofrontalis muscle (a muscle of facial expression)
Skin Innervated: None
Path: Emerges from the parotid plexus and supplies muscles of facial expression in
the temporal region
mandibular branch of the Facial nerve
Origin: A branch of the facial nerve proper
Muscles Innervated: Depressor anguli oris muscle (a muscle of facial expres- sion)
Skin Innervated: None
Path: Emerges from the parotid plexus and supplies muscles of facial expression in
the mandibular region
Facial nerve proper (VII)
Path: The facial nerve (CN VII) emerges from the junction of the pons and medulla as two divisions: the motor root and the intermediate nerve. The larger motor root (facial nerve proper) innervates the muscles of facial expression, and the smaller intermediate nerve carries taste, parasympathetic, and somatic sensory fibers. The facial nerve first traverses the posterior cranial fossa, enters the internal acoustic meatus, and then the facial canal. The nerve proceeds a short distance anteriorly within the temporal bone before turning abruptly posteriorly to course along the medial wall of the tympanic cav- ity. This sharp bend, the geniculum of the facial nerve, is the site of the geniculate gan- glion (sensory ganglion of CN VII). From the geniculate ganglion emerges the greater petrosal nerve and the remainder of the facial nerve. The facial nerve then gives off the nerve to the stapedius and the chorda tympani before exiting the facial canal via the sty- lomastoid foramen as the facial nerve proper. The facial nerve proper gives off the pos- terior auricular branch before entering the parotid gland and forming the parotid plexus. The plexus gives rise to the temporal zygomatic, buccal, mandibular and cervi- cal terminal motor branches.
Components:
Somatic (branchial) motor:
Location of cell bodies: Pons
Branches: Temporal, zygomatic, buccal, mandibular, cervical
Actions: Motor innervation to muscles of facial expression and scalp including: frontal belly of occipitofrontalis (temporal branch), orbicularis oculi (zygomatic branch), orbicularis oris, buccinator, levator labii superioris, zygomaticus major, zygomaticus minor (buccal branch), depressor anguli oris (mandibular branch) and platysma (cervical branch). The facial nerve also supplies the stapedius of middle ear, stylohyoid and posterior belly of digastric.
Special sensory (taste)
Location of cell bodies: Geniculate ganglion. Synapse: nuclei of solitary tract
Actions: Taste from anterior two thirds of tongue and palate
Somatic (general) sensory
Location of cell bodies: Geniculate ganglion. Synapse: sensory nucleus of trigemi- nal nerve.
Actions: Sensation from skin of external acoustic meatus
Visceral motor
Location of cell bodies: Presynaptic: pons (superior salivatory nucleus). Postsynap- tic: pterygopalatine ganglion; submandibular ganglion.
Actions: Parasympathetic innervation to submandibular and sublingual salivary glands, lacrimal gland, and glands of nose and palate.
superficial temporal artery
Source: Small terminal branch of the external carotid artery
Course: Ascends anterior to the ear to the temporal region and ends in the scalp to supply blood to the facial muscles and skin of the frontal and temporal regions
maxillary artery
Source: A branch of the external carotid artery
Course: Arises posterior to the neck of the mandible, travels anteriorly deep to the neck of the mandibular condyle and then passes superficial or deep to the lateral pterygoid muscle. The artery passes through the pterygomaxillary fissure to en- ter the pterygopalatine fossa
Divisions: The maxillary artery is divided into three parts by its relation to the lateral pterygoid muscle
First Portion (Retromandibular):
Deep auricular artery-supplies the external acoustic meatus
Anterior tympanic artery-supplies the tympanic membrane
Middle meningeal artery-supplies the dura mater and calvaria Accessory meningeal arteries-supplies the cranial cavity
Inferior alveolar artery-supplies the mandible, gingivae (gums), teeth and
floor of the mouth
Second Portion (Pterygoid):
Deep temporal arteries (anterior and posterior)-ascend to supply the
temporalis muscle.
Pterygoid arteries-supply the pterygoid muscles.
Masseteric artery-passes laterally through the mandibular notch to supply the
masseter muscle.
Buccal artery-supplies the buccinator muscle and mucosa of the cheek.
Third Portion (Pterygopalatine):
Posterior superior alveolar artery-supplies the maxillary molar and
premolar teeth, the buccal gingiva, and the lining of the maxillary sinus Infra-orbital artery-supplies the inferior eyelid, lacrimal sac, infra-orbital
region of the face, side of the nose, and the upper lip
Descending palatine artery-supplies the mucous membrane and glands of
the palate and palatine gingiva
Artery of pterygoid canal-supplies the superior part of the pharynx, the
pharyngotympanic (auditory) tube, and the tympanic cavity
Pharyngeal artery-supplies the roof of the pharynx, the sphenoidal sinus, and
the inferior part of the pharyngotympanic tube
Sphenopalatine artery (termination of the maxillary artery)-supplies
the lateral nasal wall, the nasal septum, and the adjacent paranasal sinuses
transverse facial artery
Source: One of two terminal branches of the external carotid artery (the other be-
ing the superficial temporal artery)
Course: Arises from the external carotid artery at the level of the ear, near the up- per part of the masseter muscle within the parotid gland. The artery crosses the face superficial to the masseter and inferior to zygomatic arch to supply the parotid gland and parotid duct and the muscles and skin of the face
superior labial artery
Source: Facial artery near the angle of the mouth
Course: The superior labial artery runs medially within the upper lip to supply the up- per lip, ala and septum of the nose.
inferior labial artery
Source: Facial artery near the angle of the mouth
Course: The inferior labial artery runs within and supplies the lower lip
angular artery
Source: Terminal branch of the facial artery
Course: Runs superiorly along the lateral edge of the nose to the medial angle (can- thus) of the eye. It supplies the superior part of the cheek and inferior eyelid (or- bicularis oculi muscle)
facial vein
Course: The facial vein provides the primary superficial venous drainage of the face. It begins at the medial angle of the eye as the angular vein where it communi- cates with the superior ophthalmic vein (which drains into the cavernous sinus). The facial vein travels inferiorly and posteriorly along the face with tributaries in- cluding the deep facial vein (which drains into the pterygoid venous plexus of the infratemporal fossa). Inferior to the margin of the mandible, the facial vein is joined by the anterior branch of the retromandibular vein before draining ei- ther directly or indirectly into the internal jugular vein.
retromandibular vein
Course: Formed by the union of the superficial temporal and maxillary veins, the retromandibular vein travels inferiorly within the parotid gland to the poste- rior border of the ramus of the mandible. It runs superficial to the external ca- rotid artery but deep to the facial nerve. At the ramus of the mandible the retromandibular vein divides into an anterior branch (which unites with the fa- cial vein) and a posterior branch. The posterior branch joins the posterior auricu- lar vein to form the external jugular vein
orbicularis oculi muscle
Proximal Attachments: Medial orbital margin; medial palpebral ligament; lacrimal bone (see green areas on image)
Distal Attachments: Skin around margin of orbit; superior and inferior tarsi (tarsal plates)
Innervation: Zygomatic branch of facial nerve (CN VII) Actions: Closes eyelids: palpebral part does so gently, orbital part tightly
orbicularis oris muscle muscle
Proximal Attachments: Medial maxilla and mandible; deep surface of peri-oral skin; angle of mouth
Distal Attachments: Mucous membrane of lips
Innervation: Buccal branch of facial nerve (CN VII)
Actions: Tonus closes mouth; phasic contraction compresses and protudes lips (kiss- ing) or resists distension (when blowing)
levator labii superioris muscle
Proximal Attachment: Medial infra-orbital margin (see green area on images) Distal Attachments: Skin and muscle of the upper lip (labii superioris) Innervation: Buccal branch of facial nerve (CN VII)
Actions: Elevates upper lip
zygomaticus major muscle
Proximal Attachment: Anterior aspect of zygomatic bone (see green area on im- ages)
Distal Attachment: Modiolus of mouth
Innervation: Buccal and zygomatic branches of facial nerve (CN VII) Actions: Draws angle of mouth upward and laterally
zygomaticus minor muscle
Proximal Attachment: Anterior aspect of zygomatic bone (see green area on im- ages)
Distal Attachment: Skin of upper lip
Innervation: Buccal and zygomatic branches of facial nerve (CN VII)
Actions: Elevates upper lip
depressor anguli oris muscle
Proximal Attachment: Tubercle of mandible (see green area on images) Distal Attachment: Modiolus of mouth
Innervation: Mandibular branch of facial nerve (CN VII) Actions: Depresses angle of mouth
occipitofrontalis muscle
Frontal belly: Proximal Attachment: Epicranial aponeurosis
Distal Attachments: Skin and subcutaneous tissue of eyebrows and forehead
Innervation: Temporal branch of facial nerve (CN VII)
Actions: Elevates eyebrows and wrinkles skin of forehead; protracts scalp (indicating surprise or curiosity)

Occipital belly: Proximal Attachment: Lateral two thirds of superior nuchal line (see green area on
images)
Distal Attachment: Epicranial aponeurosis
Innervation: Posterior auricular branch of facial nerve (CN VII)
Actions: Retracts scalp; increasing effectiveness of frontal belly of occipitofronta- lis
supraorbital nerve
Origin: The larger of two terminal branches of the frontal nerve (the other being the supratrochlear nerve)
Muscles Innervated: None
Skin Innervated: Mucosa of frontal sinus; skin and conjunctiva of middle of supe-
rior eyelid; skin and pericranium of anterolateral forehead and scalp
Path: The supraorbital nerve continues anteriorly along the roof of the orbit before it exits the skull through the supraorbital foramen to supply the upper eyelid, con- junctiva of the eye, the frontal sinus and the skin from the forehead extending to the middle of the scalp. The supraorbital nerve bifurcates into two branches, the medial and lateral supraorbital branches which ascend the forehead.
infraorbital nerve
Source: Third branch of the maxillary artery
Course: Travels along the infraorbital groove and canal with the infraorbital nerve before emerging onto the face through the infraorbital foramen, beneath the in- fraorbital head of the levator labii superioris muscle
mental nerve
Origin: Terminal branch of inferior alveolar nerve (branch of the mandibular
nerve, V3)
Muscles Innervated: None
Skin Innervated: Skin of chin; oral mucosa of lower lip
Path: Emerges from the mandibular canal via the mental foramen on the anterolateral
aspect of the body of the mandible