Intro to Neck and Anterior Triangle

What does the superficial neck fascia contain?

CT continuous throughout the body

cutaneous nerves and vessels, Fat, muscles of facial expressions

What does deep neck fascia contain?

connective tissue which envelops muscles, vessels and organs

What are the attachment points of deep fascia?

Skull and Mandible

What is investing fascia?

fascia that encases a muscle

What is the name of CN I and what does it do?

Olfactory-smell

What is the name of CN II and what does it do?

Optic- Sight

What is the name of CN III and what does it do?

Occulomotor- movement of extrinsic eye muscles, parasympathetic to eye

What is the name of CN IV and what does it do?

Trochlear- movement of superior oblique muscle

What is the name of CN V and what does it do?

Trigeminal – sensation to face, oral cavity and movement of muscles of mastication

What is the name of CN VI and what does it do?

Abducens – movement of lateral rectus muscle

What is the name of CN VII and what does it do?

Facial – motor to muscles of face, taste, parasympathetic to salivary glands

What is the name of CN VIII and what does it do?

Vestibulochochlear – hearing and balance

What is the name of CN IX and what does it do?

Glossopharyngeal – Sensation to throat and tongue, taste, parasympathetic to salivary glands

What is the name of CN X and what does it do?

Vagus – motor to throat and larynx and parasympathetic to thorax and abdomen

What is the name of CN XI and what does it do?

Spinal Accessory – motor to trapezius and sternocleidomastoid and pharyngeal plexus

What is the name of CN XII and what does it do?

\n Hypoglossal – motor to tongue muscles

Which CN nuclei are located in the brain?

CN I and CN II

Which CN nuclei are located in the brain stem?

CN III- XII

Which CN are all sensory?

CN I, CN II, CN VIII

Which CN are all motor?

CN IV, CN VI, CN XI, CN XII

Which CN are mixed?

CN III, CN V, CN VII, CN IX, CN X

Which CN carry parasympathetic fibers along with other nerve types?

CN III, CN VII, CN IX, CN X

What are the superficial muscles of the neck?

Platysma, Sternocleidomastoid muscle, and Trapezius

What innervates the platysma?

CN VII (facial nerve)

What are the attachments of the platysma?

Mandible to the skin of chest

What does the platysma do?

Muscle of facial expression, only moves skin

What are the attachments of the sternocleidomastoid (SCM)?

manubrium of sternum and clavicle; lateral aspect of mastoid process and superior nuchal line

What innervates the sternocleidomastoid (SCM)?

Accessory nerve (CN XI)

What is the action of the sternocleidomastoid (SCM)?

Bilateral- Flex neck

Unilateral- face turns opposite side, chin up

What are the attachments of the Trapezius?

vertebral column, scapula and skull

What is the action of the trapezius?

Shrugging

What innervates the trapezius?

CN XI (Spinal Accessory)

What are the functions of the hyoid bone?

Maintains open airway and provides place for muscles to attach

What are the suprahyoid muscles of the neck?

Mylohyoid, Geniohyoid, Stylohyoid, Digastric

what are the attachments of the mylohyoid m.?

Midline Raphe, mandible and hyoid attachment, floor of the oral cavity

What innervates the mylohyoid muscle?

nerve to mylohyoid (V3 which is a branch of CN V)

What innervates the geniohyoid m.?

C1

What are the attachments of the Geniohyoid m.?

mandible and hyoid attachment, floor of oral cavity

What innervates the stylohyoid muscle?

CN VII

What are the features of the Stylohyoid m.?

Tendinous and muscular, wraps around tendon of digastric m.

What is the attachments of the stylohyoid m.?

Styloid process and hyoid

How many bellies does the diagastric m. have?

2 bellies

What innervates the anterior belly of the digastic m.?

V3

What innervates the posterior belly of the digastic m.?

CN VII

How does the digastric m. connect to the hyoid?

doesn’t attach directly; fibrous sling

What do the Suprahyoid muscles do?

Elevate the hyoid

What are the infrahyoid muscles of the neck?

sternohyoid, omohyoid, sternothyroid, thyrohyoid

What innervates the sternohyoid m.?

Ansa cervicalis

What does the Ansa cervicalis contain innervations from?

C1, C2, C3 (all motor)

What innervates the omohyoid m.?

Ansa cervicalis

what innervates the sternothyroid m.?

Ansa cervicalis

What are the attachments of the omohyoid?

shoulder and 1st rib

What innervates the thyrohyoid?

C1 (EXCEPTION)

What is the action of the infrahyoid muscles?

All depress the hyoid

What are the boundaries of the posterior triangle of the neck?

Anterior- posterior border of SCM

Posterior- Anterior border of trapezius m.

Inferior. Middle 1/3 of clavicle

What are the interior triangle boundaries of the neck?

Posterior- Anterior border of SCM

Superior- Inferior border of mandible

Anterior- Anterior midline

What are the subdivisions of the anterior triangle of the neck?

submandibular, submental, carotid, and muscular triangles

What is the roof of all the triangles?

skin, fascia, and platysma

What veins are contained in the Anterior triangle?

External jugular, retromandibular branches, facial, common facial, and internal jugular vein

What nerves are contained in the anterior triangle?

cervical plexus branches, mylohyoid from trigeminal (V3), Cervical branch of facial (VII) , Vagus (X), Spinal accessory (XI), Hypoglossal (XII)

Where does the common carotid a. split?

at C3

What does the common carotid a. split into?

Internal and External carotid a.

What are the branches of the internal carotid a.?

no branches in the neck

What are the branches of the external carotid?

Ascending pharyngeal, superior thyroid a. (branch: superior laryngeal), Lingual a., Facial a. (branch: submental), Occipital

Which anterior triangle subdivision is the only one that is naturally unpaired?

Submental Triangle

What are the boundaries of the submental triangle?

Anterior belly of right digastric m.

Anterior belly of left digastric m.

Body of hyoid

floor- mylohoid

What are the contents of the Submental triangle?

Anterior jugular vein, submental lymph nodes

What are the boundaries of the muscular triangle?

sternocleidomastoid, superior belly of the omohyoid, and midline

floor- sternohyoid and sternothyroid

What are the contents of the muscular triangle?

Strap muscles \n Larynx \n Trachea \n Thyroid gland \n Parathyroid glands

Esophagus

branches of the Ansa Cervicalis \n Superior Thyroid artery & vein \n Inferior Thyroid vein \n Anterior Jugular \n Lymph nodes

Describe the thyroid gland.

2 lobes joined together in midline by isthmus (2/3rd tracheal rings)

What are the vertebral levels of the thyroid gland?

Superior limit: C5

Inferior Limit: T1

Where are parathyroid glands?

on the posterior surface of the thyroid gland

What are the boundaries of the carotid triangle ?

Sternocleidomastoid

posterior belly of the digastic

superior belly of the omohyoid

What makes up the floor of the carotid triangle?

hypoglossus, thyroid, middle constrictor, inferior constrictor

What major arteries are in the carotid triangle?

Common carotid a, internal carotid a., external carotid a.

What is the carotid sinus?

bifurcation of common and internal carotid

what does the internal carotid artery contain?

baroreceptors and chemoreceptors

T or F. The carotid triangle contains all the branches of the external carotid a.

true

What does the superior laryngeal a. travel through?

the thyrohyoid membrane

What veins are present in the carotid triangle?

Internal jugular v.

common facial v.

Lingual v.

superior thyroid v.

middle thyroid v.

where do all the veins in the carotid triangle empty into?

internal jugular v.

What does the internal jugular v. join with and what does it form heading back to the heart?

joins with subclavian to form brachiocephalic v.

What makes up the common facial vein?

facial v. and anterior of retromandibular vein

What nerves are contained in the carotid triangle?

Vagus n., superior laryngeal n. (branches: internal and external laryngeal branches), Accessory n., hypoglossal n., Ansa Cericalis, Sympathetic trunk

Where is the sympathetic trunk?

behind the carotid sheath

What does the sympathetic trunk contain?

superior, middle, and inferior cervical ganglia

What is in the carotid sheath?

internal jugular v., Vagus n., Common carotid (lower part) and/ or internal carotid (upper part), Deep cervical lymph nodes

What are the 4 important relationships the hypoglossal n. is involved in?

1. The hypoglossal n. makes anterior bend; runs under occipital
2. hypoglossal n. crosses over lingual a. (loop of lingual)
3. hypoglossal n. travels underneath post digastric
4. C1 travels with hypoglossal to thyrohyoid

What are the visceral structures are in the carotid triangle?

Larynx (small part), thyroid (small part), deep cervical Lymph modes

What are the boundaries of the submandibular triangle?

Anterior- anterior belly of digastric m.

Posterior- posterior belly of digastric m.

Superior- inferior border of the mandible

What makes up the floor of the submandibular triangle?

Mylohyoid m., hyoglossus m., and middle pharyngeal constrictor m.

What are the attachments of the hyoglossus m.?

greater horn of hyoid and lateral surface of tongue

What innervates the hypoglossal m?

hypoglossal n (XII)

What are the attachments of the middle pharyngeal constrictor m?

greater horn or hyoid and stylohyoid ligament, into the muscle of other side at midline raphe

What innervates the middle pharyngeal constrictor m.?

pharyngeal plexus (CN X and XI)

What are the contents of the submandibular triangle?

Stylohyoid m., submandibular gland, submandibular lymph nodes, facial artery (major branch- submental artery), facial vein, hypoglossal n., mylohyoid n., lingual artery, lingual n.

What does the facial artery and branch suppy?

glands and face

T or F. The facial vein does not follow the facial artery.

False

Where is the hypoglossal n. and what does it innervate?

lies on the hyoglossus m. and innervates the tongue

Where does the lingual artery travel?

under hyoglossus m.