L30. The Neck

Question 1

Where does the neck run from/to?

Answer 1

Mandible and skull to thoracic inlet (first rib)

Question 2

How is the neck divided?

Answer 2

Into anterior and posterior regions by the sternocleidomastoid muscle.

Question 3

Where does the sternocleidomastoid’s proximal attachment lie?

Answer 3

Mastoid process (bony prominence behind the ear)

Question 4

Where is the distal attachment of the sternocleidomastoid?

Answer 4

The sternum and clavicle

Question 5

What are the 2 main functions of the sternocleidomastoid muscle?

Answer 5

Tilts the head downwards

Turns head from side to side

Question 6

Which 2 habits increase the risk of head and neck cancers by 10x?

Answer 6

Smoking and alcohol

Question 7

Name the 3 regions which make up the anterior triangle of the neck.

Answer 7

Sternocleidomastoid, lower border of the mandible and the midline of the neck (profile).

Question 8

Name 3 muscles in the anterior portion of the neck.

Answer 8

Mylohyoid - forms a hammock under the mandible
Anterior belly of digastric - 2 strands of muscle running from centre of the mandible down into the neck.
Infrahyoid “strap” muscle - sternohyoid, sternothyroid, thyrohyoid, omohyoid

Question 9

Name the 4 skeletal elements in the anterior portion of the neck.

Answer 9

Thyroid cartilage
Cricoid cartilage
Hyoid bone
Trachea

Question 10

Name the 4 glands in the anterior portion of the neck and whether they are endocrine or exocrine.

Answer 10

Thyroid and parathyroid glands - both endocrine. They release hormones into the blood.
Submandibular gland - exocrine so secretions are made via a duct.
Sublingual

Question 11

Name the connective tissue which encloses the thyroid gland.

Answer 11

Pre-tracheal fascia

Question 12

Name the arteries which supply the thyroid gland.

Answer 12

Superior thyroid artery (external carotid) and inferior thyroid artery (thyro-cervical trunk)

Question 13

How could you feel for an enlarged thyroid gland?

Answer 13

A lump when swallowing

Question 14

Name the small area of thyroid gland which connects the left and right lobes.

Answer 14

Isthmus

Question 15

Name the third lobe of the thyroid gland, present in 10-30% of the population.

Answer 15

Pyramidal lobe is a projection from the isthmus.

Question 16

Name the 2 sets [parathyroid] which sit inside the thyroid gland.

Answer 16

Superior set and inferior set

Question 17

What does parathyroid hormone do?

Answer 17

Increases the uptake of calcium from bone, gut and kidneys.

Question 18

Why must calcium levels be maintained?

Answer 18

If it is not maintained, muscles (eg heart) cannot contract.

Question 19

What 2 conditions can arise if the parathyroid glands are removed (eg after a thyroidectomy)?

Answer 19

Tetany (extra muscle contractions)

Atrophy (muscle wastage)

Question 20

Name the 3 nerves present in the neck’s anterior triangle and the structures each innervates.

Answer 20

Vagus nerve - larynx, trachea, rest and digest
Phrenic nerve - originates in the neck, C3,4,5 keeps the diaphragm alive.
Hypoglossal - tongue motor control

Question 21

Which nerve used to be divided to help with symptoms of TB?

Answer 21

Phrenic nerve

Question 22

Between which cervical vertebrae does the common carotid artery bifurcate?

Answer 22

C4 and C5

Question 23

80% of the brain’s blood supply comes from 1 artery, and 20% from another. What are these?

Answer 23

80% = internal carotid artery
20% = vertebral artery

Question 24

Name the vessels present in the anterior triange

Answer 24

common carotid artery

jugular veins

Question 25

Name the 5 jugular veins, and where each runs.

Answer 25

1. Anterior - down neck midline 2. Retromandibular - brain to in front of spine 3. internal jugular - deep, in front of vertebrae 4. External jugular - superficial, slightly behind vertebrae 5. vertebral vein - deep, runs through vertebrae

Question 26

Name the 2 nerves in the posterior triangle of the neck.

Answer 26

``` Accessory nerve (motor, supplies trapezius and sternocleidomastoid) Brachial plexus - from spinal cord to underarm (motor and sensation) from C5,6,7,8 and T1. ```

Question 27

What are lymph nodes?

Answer 27

Small structures which drain lymph fluid (eg lymphocytes) to prevent the spread of infection. They drain from superficial to deep.

Question 28

Give 2 examples of causes of neck swellings.

Answer 28

Enlarged thyroid gland (goitre) | cysts