EXAM 2 - Regional Neck Anatomy

Anterior cervical triangle borders

1. anterior border of Sternocleidomastoid

2. inferior margin of mandible

3. Anteromedial line of neck

posterior cervical triangle borders

1. posterior border of SCM

2. anterior border of traps

3. middle 1/3 of clavicle

Major Vessels of the Neck

► Arterial

◦ Brachiocephalic a (not paired)

◦ L/R Common carotid aa (CCA)

◦ External carotid aa

◦ Internal carotid aa

◦ L/R Subclavian aa

Major Vessels of the Neck

► Venous

◦ L & R subclavian vv

◦ External Jugular vv (EJV)

◦ Internal Jugular vv (IJV)

◦ L & R brachiocephalic vv

Brachiocephalic a

► Arises directly off of the aortic arch (1st branch)

► A single vessel that gives rise to:

◦ 1. R subclavian artery

◦ 2. R CCA

Common Carotids (CCA)

► Right CCA

◦ Arises from the brachiocephalic artery

► Left CCA

◦ Arises from the aortic arch - the second branch

Both CCAs run cranially in neck through

__________________ just deep to ant border of

______

the carotid sheath

SCM

carotid triangle borders

superior belly of omohyoid muscle

posterior belly of digastric muscle

anterior border of SCM

Carotid Triangle - contents

common carotid arteries and branches

internal and external carotid arteries

internal jugular veins and tributaries

vagus nerve (in the middle)

hypoglossal nerve

spinal accessory n

thyroid gland

larynx

deep cervical lymph nodes

branches of the cervical plexus

Carotid Sheath - contents (must know all 7)

1. CCAs (L&R)

2. internal carotid arteries

3. internal jugular veins

4. vagus n (shiny and pull and the head will come up...extremely strong)

5. cervical lymph nodes

6. carotid sinus

7. sympathetic n fibers

Common Carotids Continued

► Above upper border of thyroid cartilage they

divide into

1. external carotid a (C)

2. internal carotid a (B)

External Carotid aa - supplies

outside of the face and skull

External Carotid aa - branches

1. superficial thyroid

2. ascending pharyngeal

3. lingual

4. facial

5. occipital

6. posterior auricular

7. superficial temporal

8. maxillary

External Carotid aa - path

upper boarder of thyroid cartilage - parotid gland behind the mandible - emerges at anterior border of SCM (with the carotid triangle)

can you palpate the External Carotid aa

yeah - its not within the carotid sheath

Internal Carotid aa - branches

NO BRANCHES IN THE NECK

Branches in the head:

1. ophthalmic

2. posterior communicating

3. anterior cerebral artery

4. middle cerebral artery

Internal Carotid aa - path

upper border thyroid cartilage throughout the neck

- enters the cranial cavity via the carotid canal (temporal bone) - terminates into anterior and middl cerebral arteries

R Subclavian aa arises

from the brachiocephalic artery

arches up and laterally over the lung pleura and runs between two muscles

what muscles does the R Subclavian aa run though

anterior scalene and the middle scalene

where does the R Subclavian aa become the axillary a

level of the first rib

Subclavian steal syndrome

Causes someone to pass out when they raise their right arm above their head

Occurs due to retrograde flow in the vertebral artery

occurs when the subclavian artery is occluded - between the right common carotid and vertebral artery - , and blood flow is diminished, or obstructed, to the head and upper extremities.

Left subclavian artery arises

directly from the aortic arch (3rd branch)

Subclavian vv

Continuation of axillary vv at level of 1st rib

path of the subclavian vv

runs through a groove (along with the subclavian a) on the superior surface of rib 1

- anterior groove is for the subclavian vein

- posterior groove is for the subclavian artery

joins with the internal jugular vein to form the brachiocephalic veins

what does the subclavian vv drain

1. External jugular vein

2. left thoracic duct

3. right lymphatic duct

External Jugular vv (EJV) - Formed

behind the angle of the mandible by the union of the posterior auricular vein and the retromandibular vein

clinical application of EJV

you can visually see the venous pressure above the clavicle in the EJV and IJV

Internal Jugular vv (IJV) - drains

brain!!, face, scalp, and neck

Internal Jugular vv (IJV) is a continuation of

sigmoid venous sinus in brain

Internal Jugular vv (IJV) - leaves the skull through what foramen

jugular foramen

Internal Jugular vv (IJV) - path

descends through the neck within the carotid sheath lateral to the vagus n and internal common carotid artery

-joins the subclavian vv behind the medial end of the clavicle to form the brachiocephalic vv

Internal Jugular vv (IJV) - major tributaries

1. facial vein

2. inferior petrosal sinus

Brachiocephalic vv (R & L) - major tributaries

IJV

Subclavian v

where does the Brachiocephalic vv begin

at the medial end of the clavicle

Platysma (O, I, A, innervation)

-Superficial & Large

► O: fascia of upper chest

► I: fascia of chin and jaw

► A: depress and draw lower lip laterally & draw up skin of chest

► N: facial n - cervical branch

Muscles of the Hyoid/Larynx - general groups and actions

► Suprahyoid Group

◦ General action - elevate

► Infrahyoid Group

◦ General action - depress

Suprahyoid Group

digastric, geniohyoid, mylohyoid, stylohyoid

Digastric (anterior)

O I A INN

O: inferior border of mandible

I: tendon attached to hyoid

A: elevate hyoid and lower mandible

INN: V3 - trigeminal N

Digastric (posterior)

O I A INN

O: mastoid

I: tendon attached to hyoid

A: move hyoid posteriorly

INN: facial N - Cervical branch

Stylohyoid - A & N

A: move hyoid backward and elevate tongue

N: Facial N

mylohyoid - A & N

A: elevate hyoid and raise the floor of the mouth and tongue

N: V3 - trigeminal

geniohyoid A&N

A: protrude hyoid and tongue

N: hypoglossal n (CN XII) and C1 nerve

Infrahyoid Group consists of

sternohyoid, sternothyroid, omohyoid, thyrohyoid

sternohyoid A&N

A: depress hyoid

N: C1-C3

sternothyroid A&N

A: depress thyroid cartilage

N: C1-C3

Omohyoid A&N

A: depress hyoid

N: C2-C3

There is an superior and inferior belly

thyrohyoid A&N

A: depress hyoid and elevate thyroid cartilage

N: hypoglossal n and C1

Anterior Cervical Vertebral Group

longus colli

longus capitis

rectus capitis anterior

rectus capitis lateralis

Longus Colli A&N

A: flex vertebral column

N: C2-C7

longus capitis OIAN

O: TP of C3-C6

I: occipital bone

A: flex vertebral column/neck

N: C1-C3

Rectus Capitis Anterior OIAN

O: C1 (atlas)

I: occipital bone

A: flex vertebral column/neck

N: C2-C3

rectus capitis lateralis OIAN

O: C1 (atlas)

I: occipital bone

A: flex vertebral column laterally

N: C2-C3

Lateral Cervical Vertebral Group

anterior, medius, and posterior scalene

scalenus anterior OIAN

O: TP of C3-C6

I: First rib

A: elevate rib 1 (inhale)

N: C2-C3

scalenus medius OIAN

O: TP of C2-C7

I: First rib

A: elevate rib 1 (inhale)

N: C2-C3

scalenus posterior OIAN

O: TP of C5-C7

I: second rib

A: elevate rib 2 (inhale)

N: C3-C5

Additional Actions of anterior and lateral cervical vertebrae

Bilateral: flexion of the vertebral column (flexion in cervical vert/neck)

Unilateral: ipsilateral neck flexion and slight rotation

Superficial Group of neck

sternocleidomastoid

SCM - OIAN

Sternal head O: manubrium of sternum

Clavicular head O: head of clavicle

Common I: mastoid process

Bilateral A: flex neck, elevate chin, draw head ventrally and sternum superiorly

Unilateral A: lateral flexion of neck, rotation of head contralaterally

Common N: C2-C3

Congenital Torticollis & Types

twisted neck - present at birth

3 major types

- Fibromatosis colli

- muscular torticollis

- spasmodic torticollis

Fibromatosis colli

- most common

- develop in SCM

- prenatal - generally occurs in a breached delivery

- results in a twisted neck from unilateral action of SCM

(this means that if the right SCM is contracted, the neck is flexed towards the right but contralaterally flex head towards the left side)

muscular torticollis

result of difficulty in delivery of baby - use of forceps usually

- treatment with a surgical release of the SCM from the origin and repair

spasmodic torticollis

- can be adult onset (not congenital)

- treat with botox

- sustained muscle spasms/contraction in the SCM - causing flexion on the impaired side and turn head contralaterally towards other side

Thyroid Gland - location

anterior aspect C5 - T1

Thyroid Gland - comprised of

- right and left lobe

- isthmus - connection between lobes

sometimes a pyramidal lobe on top of isthmus

Thyroid Gland - arterial supply

superior and inferior thyroid arteries

-unpaired thyroid ima artery (only in 10% of population)

Thyroid Gland - venous drainage

superior, middle, inferior thyroid veins

Thyroid Gland - lymphatic drainage

Prelaryngeal node, pretrachial node, and paratrachial node

Thyroid Gland -innervation

superior, middle, and inferior cervical sympathetic ganglia

- vasomotor: constriction of blood vessels to inhibit the blood flow (this is innervation that controls blood flow to organ by constricts blood vessels that supply it)

Parathyroid Glands - location

embedded in posterior surface of the thyroid gland

Parathyroid Glands - comprised of

2 superior and 2 inferior glands

can have more=ectopic glands as well

Parathyroid Glands - arterial supply

thyroid arteries

Parathyroid Glands - venous supply

thyroid veins

Parathyroid Glands - lymphatic drainage

cervical and paratrachial nodes

Parathyroid Glands - innervation

superior, middle, and inferior cervical sympathetic ganglia

- vasomotor: constriction of blood vessels to inhibit the blood flow

important in surgery of a thyroidectomy to leave the parathyroid glands behind and the nerves and blood supply

Larynx - functions

► Cartilagenous chamber about 4cm

► Primary fxn - keeping things out of airway (solids and liquids)

► Secondary fxn - phonation

Epiglottis

A cartilaginous flap of tissue that guards opening of larynx

vestibular folds

false vocal cords - also prevent food and water from entering airway

Laryngeal Muscles - Extrinsic m

-originate outside larynx and insert on larynx

Move larynx as a whole

◦ 2 groups

● 1. Depressors

● A. Examples: infrahyoids

● 2. Elevators

● A. Examples: suprahyoids

Laryngeal Muscles - intrinsic m

-originate and insert on larynx

Move individual larynx parts

● 1. alter length & tension - of vocal cords

● 2. size & shape - rim glottidis

Walls of the Larynx - 2 folds

interior wall has 2 folds on each side

- superior and inferior vestibular folds

superior vestibular folds

false vocal cords

close the larynx off during swallowing

play no role in speech

inferior vestibular folds

true vocal cords

produce the sound when air is force through/between them

contains the vocal ligaments

glottis

the vocal apparatus of the larynx - opening of larynx

-your vocal cords and the opening between them, the rima glottidis

rima glottidis

aperature/space between vocal folds

opening between vocal cords

Abduction and adduction of vocal cords

Variations in Shape of Rima Glottidis

forced respiration= talking loudly

phonation=normal talking

Action of Vocal Cords - intrinsic muscles

control vocal cords

Action of Vocal Cords - innervation

recurrent laryngeal n - off of vagus n

Intrinsic muscles of vocal cords action and innervation

control vocal cords

Recurrent laryngeal nerve (branch off vagus nerve...recurrent because have to go back upwards)

Action of Vocal Cords - taut cords

high pitched sounds

Action of Vocal Cords - slack cords

lower pitched sounds

Action of Vocal Cords - adult males

- longer and thicker

- vibrate more slowly

- produce lower pitched sounds

Action of Vocal Cords - loudness

determined by how much air is forced through between the vocal cords

what forms sound? what forms words?

cords produce crude sounds that are formed into

words by the pharynx, oral cavity, tongue & lips