9.27 - Neck And Posterior Triangle

Front 1

neck

Back 1

from lower border of mandible to first rib
connects head to thorax and upper limb

Front 2

mandible

Back 2

mental protuberance (forms the chin)

Front 3

Hyoid bone

Back 3

Has body, greater and lesser horns
Articulates with no other bone
Located at vertebral level VC3

Front 4

Thyroid cartilage

Back 4

laryngeal prominence
More prominent in men
VC4,5

Front 5

cricoid cartilage

Back 5

Below thyroid cartilage at V6
Continues with trachea

Front 6

Suprasternal notch

Back 6

Formed by manubrium of sternum

Front 7

Cervical vertebrae

Back 7

7; form the bony posterior elements of the neck

Front 8

Torticollis

Back 8

(wryneck)
flexion deformity of neck, usually due to fibrosis and shortening of SCM

Front 9

Congenital torticollis

Back 9

complication of vaginal delivery

Front 10

Superficial fascia (cervical)

Back 10

Fat, platysma muscle

Front 11

Deep cervical fascia

Back 11

3 layers:
1. Superficial cervical investing
2. pretracheal
3. Prevertebral

(these 3 layers associate to form the carotid sheath in the anterior neck)

Front 12

Sternocleidomastoid muscle - origin

Back 12

(bisects neck diagonally)
Origin: 2 heads from the sternum and clavicle

Front 13

Sternocleidomastoid muscle - insertion

Back 13

mastoid processes behind the ear

Front 14

Sternocleidomastoid muscle - innervation

Back 14

spinal accessory nerve (CN XI)

Front 15

Sternocleidomastoid muscle - action

Back 15

alone: laterally flexes head, rotates head to opposite side
Together: forcibly flex head and neck.

Front 16

Cervical fascia

Back 16

Superficial fascia
deep cervical fascia

Front 17

Superficial cervical investing fascia

Back 17

spinous processes of cervical vertebrae and ligamentum nuchae.

Front 18

Pretracheal fascia

Back 18

invests the viscera of the neck - pharynx, larynx, trachea, esophagus, thyroid and parathyroid glands

visceral compartment - space within the pretracheal fascia

Front 19

prevertebral fascia

Back 19

originates from spines of cervical vertebrae
aka scalene fascia (envelopes the scalene muscles)

splits into 2 layers. Anterior layer is called "alar fascia".

Danger space - btw alar fascia and posterior layer (covering the vertebrae) = route for spread of infection

Extends into axilla as axillary sheath (investing the brachial plexus and subclavian vessels = axillary block)

Front 20

retropharyngeal space

Back 20

between pretracheal and alar portion prevertebral fascia

Front 21

Carotid sheath

Back 21

ensheaths the carotid artery, internal jugular vein and vagus nerve

Front 22

Anterior and posterior triangles of neck

Back 22

Divided by SCM

Front 23

Anterior cervical triangle

Back 23

Boundaries: anterior edge of SCM, lower border of body of the mandible, midline of the neck from chin to suprasternal notch.
subdivided into 4 smaller triangles

Front 24

Posterior cervical triangle

Back 24

Boundaries: anterior edge of trapezius, posterior edge of SCM, middle 1/3 of
clavicle. The inferior belly of the omohyoid muscle crosses the triangle separating it further into supraclavicular (lower) and occipital (upper) triangles.

Front 25

Scalene muscles - insertion

Back 25

anterior, middle - 1st rib
Posterior scalene- 2nd rib

Front 26

anterior scalene - origin

Back 26

C3-C6

Front 27

middle scalene - origin

Back 27

C2-C7

Front 28

posterior scalene - origin

Back 28

C5-C7

Front 29

scalene muscles - innervation

Back 29

VPRs

Front 30

Scalene muscles - action

Back 30

raise first and second ribs

Front 31

thoracic outlet syndrome

Back 31

nerve compression - may occur where brachial plexus/subclavian artery passes between anterior and middle scalenes

Front 32

brachial plexus - location relative to scalenes

Back 32

roots and trunks of BP pass between anterior and middle scalenes, into posterior triangle

Front 33

subclavian artery - loc

Back 33

passes btw anterior and middle scalene muscles

Front 34

Branching of subclavian artery

Back 34

split by anterior scalene
1. vertebral artery, internal thoracic artery, thyrocervical trunk
2. costocervical artery
3. dorsal scapular artery (50% of the time)

Front 35

thyrocervical trunk

Back 35

from subclavian artery
gives origin to inferior thyroid, ascending cervical, transverse cervical, suprascapular arteries

Front 36

thoracic outlet syndrome

Back 36

nerve compression - may occur where brachial plexus/subclavian artery passes between anterior and middle scalenes

Front 37

brachial plexus - location relative to scalenes

Back 37

roots and trunks of BP pass between anterior and middle scalenes, into posterior triangle

Front 38

subclavian artery - loc

Back 38

passes btw anterior and middle scalene muscles

Front 39

Branching of subclavian artery

Back 39

split by anterior scalene
1. vertebral artery, internal thoracic artery, thyrocervical trunk
2. costocervical artery
3. dorsal scapular artery (50% of the time)

Front 40

thyrocervical trunk

Back 40

from subclavian artery
gives origin to inferior thyroid, ascending cervical, transverse cervical, suprascapular arteries

Front 41

Costocervical trunk

Back 41

divides into deep cervical and the highest intercostal

Front 42

Subclavian vein

Back 42

superficial to anterior scalene
its main tributaries = external jugular, transverse cervical veins

Front 43

phrenic nerve

Back 43

C3,4,5
go thru superficial surface of anterior scalene (in prevertebral fascia) to reach thorax

Front 44

cervical plexus

Back 44

formed by the VPRs of the upper 4 cervical nerves

Front 45

superficial nerves of the neck

Back 45

cutaneous nerves:
lesser occipital
great auricular
transverse cervical
supraclavicular nerves

muscular branches:
ansa cervicalis
phrenic nerve

Front 46

lesser occipital

Back 46

C2
ascends toward mastoid process to supply skin behind ear

Front 47

great auricular

Back 47

c2, c3
may course with external jugular to supply external ear and the skin in front of the ear

Front 48

transverse cervical

Back 48

c2,3

crosses over SCM, dividing into upper and lower branches supplying most of the skin of the anterior neck

Front 49

supraclavicular nerves

Back 49

c3,4

medial branch to skin over lower SCM,
intermediate branch to skin over lower part of posterior triangle and thorax,
lateral branch to skin over the tip of the shoulder.

Front 50

ansa cervicalis

Back 50

c1,2,3
innervates anterior triangle muscles

Front 51

phrenic nerve

Back 51

c3,4,5
innervates the diaphragm

Front 52

external jugular vein

Back 52

formed by the union of the posterior auricular and
retromandibular veins. Crosses superficial to the SCM, drains into the subclavian vein.

Front 53

Anterior jugular veins

Back 53

lie just superficial in the anterior triangle at the level of the hyoid bone and typically drain into the external jugular near the subclavian vein.

Front 54

Spinal accessory nerve injury

Back 54

weakness in turning head to opposite side

Front 55

subclavian vein puncture

Back 55

to administer fluids, medications, etc.

Front 56

phrenic nerve block

Back 56

unilateral
problem in patients with COPD