Head and neck 1.1 general anatomy

Question 1

What 4 anatomical landmark features lie within the neck, and what is their relation to each other?

Answer 1

hyoid bone

thyroid cartilage

Cricoid cartilage

thyroid gland.
(in this order)

Question 2

What attaches to the hyoid bone?

Answer 2

8 strap like muscles, 4 above (suprahyoid) and 4 below (infrahyoid).
They aid elevation and depression of the hyoid during swallowing.

Question 3

What are the 3 large muscles of the neck?

Answer 3

Sternocleidomastoid
Platysma
Trapezius

Question 4

What nerves innervate the large muscles of the neck?

Answer 4

trapezius- spinal accessory muscle

Sternocleidomastoid- spinal accessory

Platysma- facial nerve

Question 5

Give features of the platysma including it’s action.

Answer 5

Broad and sheetlike, covering many features underneath it-including sternocleidomastoid.
Superficial.
Action- draws corners of mouth down, skin of neck moves superiorly if teeth are clenched (grimace)

Question 6

Give features of the sternocleidomastoid muscle including its action.
Where does it originate and insert?

Answer 6

thick, strap like muscle coming from the mastoid process of the temporal bone to the clavicle and sternum.
It’s action unilaterally- to tilt the neck in that dire ction, bilaterally- flexion at the neck

Question 7

give features of the trapezius, including origin, insertion and action.

Answer 7

Large fan like muscle.
Comes from the base of skull, nuchal ligament, spinous process’ of vertabrae, and insters into the lateral 1/3 of the clavicle, acromion and spine of scapula.
action is to elevate the shoulders.

Question 8

How do you test the integrity of the trapezius muscle and the sternocleidomastoid muscle?

Answer 8

trapezius- shurg shoulders against resistance.

sternocleidomastois- rotate head against resistance (look for it protruding, should be visible)

Question 9

What are the borders of the anterior triangle?

Answer 9

• invisible line down the midline
• inferior margin of the mandible
• anterior border of the sternocleidomastoid

Question 10

What are the borders of the posterior triangle?

Answer 10

• posterior border of the sternocleidomastoid
• superior border of middle clavicle
• anterior margin of trapezius

Question 11

what structures are found within the posterior triangle?

Answer 11

Muscles- including omohyoid, and levator scapulae, scalenes
Vasculature- external jugular vein, subclavian vein, transverse cervical and suprascapular veins and accompanying arteries,
Nerves- accessory nerve, cervical plexus, phrenic nerve, brachial plexus trunks.

Question 12

Whats the significance fo the omohyoid in the posterior triangle?

Answer 12

It divides it into 2 smaller triangles:

The occipital and the subclavian.

Question 13

whats the function of the facial layers?

Answer 13

Fascial layers envelope structures and allow ease of movement over each other, eg when turning the head, or swallowing.
They also contain spread of infection, so it cannot spread too deep, or between the layers.

Question 14

What different fascial layers are there in the head and neck?

Answer 14

Superficial fascia-

Deep cervical fascial layers (investing, pre-tracheal, pre-vertebral, carotid sheath)

Question 15

Describe the superficial cervical fascia.

Answer 15

Loose connective tissue layer which contains fat, the platysma, cutaneous nerves and vessels, and superficial lymph nodes.

Question 16

What is the retropharyngeal space?

Answer 16

The space between the prevertabral, pretracheal and carotid sheaths.

Question 17

What’s the significance of the retropharyngeal space?

Answer 17

It communicates with the mediasteinum.

Therefore any infection has potential to spread down into the mediasteinum and cause mediasteinitis (high mortality)

Question 18

What surgical procedures may introduce infection into the pre-tracheal space?

Answer 18

Tracheostomy, or other means of inserting surgical airways.

Question 19

What innervates the muscles of facial expression?

Answer 19

Facial nerve (CN VII)

Question 20

What innervates muscles of mastication?

Answer 20

Trigeminal nerve (CN V)

Question 21

What are the 3 divisions of the trigeminal nerve? what do they innervate?

Answer 21

Opthalmic- sensory to forehead, nose

Maxillary- sensory to nose, cheeks

Mandibular- sensory to chin, jaw. Motor to muscles of mastication.

Question 22

What are the 5 key branches of the facial nerve?

Answer 22

• temporal
• zygomatic
• buccal
• (marginal) mandibular
• cervical

Question 23

What other functions other than motor, does the facial nerve have?

Answer 23

Special sensory to the anterior 2/3 of tongue (chorda tympani)
parasympathetic innervation to submandibular and sublingual glands

Question 24

What important relationship does the facial nerve have?

Answer 24

The parotid gland, it runs through but doesn’t innervate.

pathology of the parotid gland can cause facial nerve palsys.

Question 25

What are the main vessels of the head and neck?

Answer 25

Common carotid arteries,

Internal and external jugular vein.

Question 26

what does the internal jugular vein drain?

Answer 26

The face and brain, (via the facial vein)