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Flashcards in deep fascia of the neck (A12) Deck (30):
1

two layers of skin

-epidermis (epithelium = keratinized stratified squamous)
-> inert/waterproof/non-vascular
-dermis (dense connective tissue)
->vascular/lymphatics/innervated by nerves/strengthens and nourishes the epithelium

2

two layers of fascia

-superficial fascia (subcutaneous tissue, distributes vessels and nerves/allows skin mobility/thermal and mechanical insulation)
-deep fascia (separates superficial from deep structures, is strong, very robust and protective)

3

type of epithelium covering the skin

keratinized stratified squamous epithelium

4

superficial cervical (neck) fascia

-immediately under skin, between skin and deep fascia/investing layer of cervical/deep fascia
-structures in the neck are surrounded by a layer of subcutaneous adipose tissue
-sub=deep
-cutaneous=skin
-adipose connective tissue
-usually a thin layer in the neck

5

deep cervical (neck) fascia

-structures in the neck are compartmentalized (kept separate from each other) by deeper layers (tubes) of bandaging: the deep fascia
-these 'tubes' of deep fascia run between and connect, the superior mediastinum to the base of the skull
-the deep fascia helps to prevent the spread of infection (if develops in the neck) from one compartment to another due to thickness
-infection tends to spread within fascial compartments by opening up 'potential spaces' (fascial planes) between the layers of fascia
-fibrous connective tissue
-deep cervical/neck fascia is divided into 3 distinct layers

6

mediastinum

a membranous partition between two body cavities or two parts of an organ, especially that between the lungs

7

contents of superficial neck fascia

-sensory nerves (of the cervical plexus)
-platysma muscles (one of the most inferior muscles of facial expression) -> right and left platysma muscles
-blood vessels (superficial veins)
-lymphatic vessels and superficial lymph nodes

8

sensory receptors in skin

-respond to touch, temperature, pain etc by triggering 'sensory' action potentials
-anterior ramus (sensory action potentials into spinal nerve) -> spinal nerve (mixed) -> posterior root (sensory), anterior root = motor

9

the cervical plexus

-plexus = single nerves intertwining
-the anterior rami of cervical spinal nerves C2,C3 and C4 mix their nerve fibres
-sensory to skin and fascia of neck, shoulder and face (over the angle of the mandible)
-sensory nerves leave the skin and superficial fascia and pierce the deep fascia to reach the posterior aspect of the spinal cord

10

brachial plexus

-C5,6,7,8 and T1 anterior rami
-nerve supply to upper arm
-5 named nerves merge together to form single trunks
->5 'new named' nerves re the result from the mixing nerve fibres from different anterior rami in the plexus
->radial nerve
->ulnar nerve
->median nerve (C5,6,7,8 and T1)
->musculocutaneous nerve
->axillary nerve

11

5 'new named' nerves that arise from the combining of several anterior rami in the plexus

->radial nerve
->ulnar nerve
->median nerve (C5,6,7,8 and T1)
->musculocutaneous nerve
->axillary nerve

12

dermatome

= area of skin innervated/supplied by single spinal nerves

13

sensory nerve supply to remainder of face that is not supplied by cervical plexus

trigeminal nerve (CN V)

14

sensory nerves that make up cervical plexus

-great auricular nerve (C2,C3) (winding to ear, contributes to supply of mandible)
-transverse cervical nerve (C2,C3) (passes transversely across neck region across belly of SCM)
-lesser occipital nerve (C2) (passing to posterior superior aspect of neck)
-supraclavicular nerves (C3,C4) (has 3 branches/end terminals - medial, intermediate and lateral)
->sensory nerves of the cervical plexus begin superficial to investing layer and SCM

15

'nerve point' of the neck

-where the cervical plexus nerves go deep, posterior to middle of SCM's posterior border
-where nerves pierce through deep fascia
-about half way down SCM muscle belly on posterior border

16

platysma muscles

-located within superficial cervical fascia
-platysma belongs to the 'muscles of facial expression' group
-this group of muscles is supplied by CN VII/facial nerve
-platysma is supplied by the cervical/5th branch of CN VII (there are 5 branches that supply the muscles of facial expression)
-not a very useful muscle
-contributes to sad face, straightens out and holds neck in place in young individuals (degenerates with age causing saggy skin)

17

superficial veins of the neck

-lie within the superficial fascia of the neck
-all part of the jugular venous system
-superficial jugular veins:
->right and left external jugular veins
->right and left anterior jugular veins
->right and left superficial jugular communicating veins
(these veins are similar between individuals however veins within the neck are very variable)

18

jugular venous system

-consists of various 'superficial' jugular veins that drain into 'deep' internal jugular veins
-superficial:
-retromandibular vein = formed by the union of the superficial temporal and maxillary veins (between ramus of mandible and SCM, retromandibular vein branches into anterior and posterior)
->posterior branch of retromandibular joins with posterior auricular to form the external jugular vein
->anterior branch of retromandibular vein joins with facial vein to form common facial vein (which pierces through deep fascia to join internal jugular vein which is deep) but also joins with anterior jugular via the superficial jugular communicating vein
->anterior jugular joins with external jugular to drain into subclavian vein (deep)
-deep:
->internal jugular vein
->subclavian vein

19

3 distinct layers of deep cervical/neck fascia (from superficial to deep)

-investing layer
-pretracheal layer
-prevertebral layer (in 3 parts including carotid sheaths)

20

spread of infection and deep cervical fascia

-it is v. easy for infection to spread up and down the inside of one of tubes/layers or up and down between the tubes/layers
-however the deep fascia is tough, making it difficult for infection to spread from one tube to another

21

investing layer of deep cervical fascia (including contents)

-surrounds the entire neck immediately deep to the superficial fascia
-within the neck it splits to contain:
->trapezius muscles
->sternocleidomastoid muscles
-splits superiorly to enclose/form protective 'capsules' for the submandibular and parotid (sits just in front of ears) salivary glands

22

contents of prevertebral layer of deep cervical fascia

-surrounds/encloses postural muscles of back and cervical vertebrae
-carotid sheaths (2 separate tubes of fascia) are located lateral to pretracheal layer of deep cervical fascia and anterior to the large prevertebral fascia tube

23

contents of pretracheal layer of deep cervical fascia

surrounds:
->trachea
->oesophagus
->thyroid gland
->4 muscles anterior to thyroid gland (strap muscles)

24

attachment sites of investing layer of deep cervical fascia

-ultimately attaches to:
->hyoid bone
->lower border of mandible
->zygomatic arches
->styloid processes
->mastoid processes
->superior nuchal line
->spinous process of cervical vertebrae
(attaches superiorly to each of the osteological land marks)

25

(spinal) accessory cranial nerve/ CN IX

-deep to investing layer of deep cervical fascia
-also deep to both of the muscles it supplies that are contained within the investing layer of deep cervical fascia:
->trapezius muscles
-> SCM muscles

26

2 components of the pretracheal layer of deep cervical fascia

1.visceral/organ part (encloses the thyroid gland, trachea and oesophagus)
2.muscular part (encloses the 'strap' muscles, which attach from the hyoid bone onto the laryngeal cartilages for movement of the larynx)

27

carotid sheaths

-right and left 'tubular fascial bandages' that run the full length of the neck
-connect the superior mediastinum to the jugular foraminae and carotid canals in the base of the skull
-lie between the investing, pretracheal and prevertebral layers of deep fascia
-contains major vessels and nerves

28

contents of carotid sheaths

-the internal jugular veins
-the carotid arteries
-the vagus nerves (CN X)
-the deep cervical chain of lymph nodes and lymphatics

29

what is the space between the pretracheal and prevertebral fascia called

-the retropharyngeal space
-infection within this space will travel right through neck (this can occur if punctured eg.due to running with pen in mouth etc)

30

what is the pretracheal fascia called after passing superior to trachea

-buccopharyngeal fascia (continuous with pretracheal fascia inferiorly)
-sits posterior to pharynx and oral cavity