Neck Anatomy I

Question 1

Platysma

Answer 1

O: within the superficial fascia covering pec major and deltoid
I: Inferior mandible, skin, subcut of teh lower face and mouth
A: draws corner of mouth, depresses mandible, elevates skin of chest
N: cervical branch of Facial N (CN VII)

Question 2

Superficial fascia of the neck

Answer 2

CT and fatty layer that fills the space bw the skin and deep fascia covering muscles

**contains the platysma

Question 3

Investing fascia

Answer 3

first deep layer just below the superficial fascia
surrounds the entirety of trap and SCM

attaches to bony prominence from ext occiptial protuberance —> inferior mandible (also nuchal ligament)
creates a CT capsule for the submandibular gland

Question 4

Infrahyoid fascia

Answer 4

From hyoid—>attaches to the pericardium

invest the infrahyoid muscles

Superficial layer: around SH and OH and creates intermediate sling
Deep: around ST and TH

fuse laterally around brachiocephalic v, fibrous pericardium via sternopericardial lig and cartoid sheath

Question 5

Cervical visceral fascias

Answer 5

encircle the viscera of the neck

made up of anterior and posterior layers which meet and fuse laterally

Question 6

pretrachial fascia

Answer 6

part of the cervical fascia
anterior to larynx, trachea, encloses thyroid gland

runs from hyoid—>pericardium

Question 7

buccopharyngeal fascia

Answer 7

4th layer, part of cervical fascia
runs from skull, covers buccinator, pharyngeal constrictors, fuses with pretrachial fascia laterally , and fuses with adventitia of esophagus inferiorally

Question 8

Prevertebral fascia

Answer 8

5th layer, continuous with nuchal fascia
encircles the vertebrae and associated muscles

**bifurcates anteriorally to make the alar fascia which attaches to the BP fascia and blends bilaterally to the carotid sheath

**forms floor of the posterior cervical triangle

Question 9

Sibsons fascia

Answer 9

prevertebral layer of fascia on underside of scalenes, creates dome of cervical plurae

Question 10

axillary sheath

Answer 10

continuation of prevertebral fascia from the scalenes laterally
covers the subclavian, axillary vessels and brachial plexus as they pass thru scalenes

Question 11

Carotid sheath

Answer 11

surrounds the common and internal carotids aa. int jugular, and vagus n

fruns from base of skull at jugular foramen to the fibrous pericardium and great vessels

**fusion of ALL deep fascias of the neck: allows infection to spread from neck into carotid sheath all the way to the diaphragm and aorta

Question 12

Suprasternal space

Answer 12

created by a split in the investing fascia

Question 13

Pretrachial or visceral space

Answer 13

b/w deep infrahyoid and pretracheal fascias

Question 14

Retroviscearl space

Answer 14

small, more anterior space b/w the BP and alar fascias, ends at CV7-TV3 where the alar fascia ends

Question 15

Danger space

Answer 15

space 4, larger, more posterior space that is located b/w teh prevertebral and alar/BC fascias from base of skull to the diaphragm

abcess here can lead to retropharyngeal abscess which lead to dysphagia and dysarthria and dissect into the posterior mediastinum
infections cannot spread to contralateral side

ex: tonsillitis that can spread down into the diaphragm

Question 16

Sternocleidomastoid

Answer 16

A:U/L: rotates head toward the opposite side while elevating chin
b/l: Flex, extension of the OA joint
N: CN XI (GSE) and C2, C3

Question 17

Posterior triangle

Answer 17

trap is posterior, SCM anterior, clavicle inferior

omohyoid inf belly divides into Occipital triangle and the omoclavicular and suprclavicular triangle

Question 18

dorsal rami of C1

Answer 18

only in 50% of individuals

small amount of GSA comves from dura lining in the posterior cranial fossa

Question 19

dorsal rami of C2

Answer 19

greater occipital n.

pierces the semispinalis capitis and trap as it ascends to innervate the posterior skull

Question 20

lesser occipital

Answer 20

ventral rami of C2 and C3

asacends the posterior border of the SCM to innervate the medial surface of the ear and skin behind the ear

Question 21

Greater auricular n.

Answer 21

C2,3 ventral rami

runs up SCM towards the angle of mandible paralleling the ext jugular v.

provides innervation to skin around mastoid, lower ear, inferior angle of mandible, and parotid region

Question 22

Transverse cervical

Answer 22

crosses the lateral surface of the SCM, deep to ext jugular v.

passes deep to platysma where it innervates the subcutaneous tissue of the anterior triangle from the mandible to the sternum

Question 23

supraclavicular n.

Answer 23

C3,4 ventral rami
arise from common trunk, then branches into the medial (to sternum and SC jt) , intermediate (skin over pec major) and lateral branches (AC jt)