11. The Neck

Question 1

What is the surface landmark of the hyoid?

Answer 1

C3

Question 2

Draw the structure of the hyoid bone.

Answer 2

Question 3

What is the surface landmark of the thyroid cartilage?

Answer 3

C3/C4

Question 4

What is the surface landmark of the cricoid cartilage?

Answer 4

C6

Question 5

What is the external occipital protuberance?

Answer 5

Question 6

Which vertebra is the vertebra prominens?

Answer 6

C7

Question 7

What are the two triangles of the neck?

Answer 7

• Anterior triangle -> Between the mid-line anteriorly and the anterior border of sternocleidomastoid posteriorly, bounded superiorly by the lower jaw. Subdivided into a further 3 triangles.
• Posterior triangle -> Between sternocleidomastoid and the trapezius muscles, bounded inferiorly by the middle 1/3rd of the clavicle.

Question 8

What are the contents of the anterior triangle of the neck?

Answer 8

• Submandibular gland
• Submandibular lymph nodes
• Hypoglossal nerve
• Submental lymph nodes
• Common carotid artery and branches
• Internal jugular vein
• Vagus nerve
• External carotid artery
• Hypoglossal nerve
• Spinal accessory nerve
• Thyroid
• Larynx
• Pharynx
• Deep cervical lymph nodes

Question 9

What are the contents of the posterior triangle of the neck?

Answer 9

• External jugular vein
• Posterior branches of cervical plexus
• Spinal accessory nerve
• Cervical plexus
• Brachial plexus trunks
• Cervical lymph nodes
• Subclavian artery
• Suprascapular artery
• Supraclavicular lymph nodes

Question 10

What forms the roof and floor of the triangles of the neck?

Answer 10

• Roof of the triangles is formed by the deep (investing) fascia that surrounds the neck like a collar, enclosing the sternocleidomastoid anteriorly and the trapezius posteriorly.
• The floor of the posterior triangle is formed by the pre-vertebral fascia, which surrounds the deep pre-vertebral muscles of the neck.

Question 11

What are the fascias of the neck you need to know?

Answer 11

• Investing (deep) fascia
• Prevertebral fascia
• Carotid sheath
• Pretracheal fascia

Question 12

What does the vagus nerve pass in?

Answer 12

Carotid sheath

Question 13

Where does the accessory nerve pass?

Answer 13

It passes under the roof of the posterior triangle to innervate the sternomastoid and trapezius.

Question 14

Where does the phrenic nerve pass?

Answer 14

Anterior to scalenus anterior, in the posterior triangle.

Question 15

What does the cervical plexus innervate?

Answer 15

• C1-C4 -> Vertebral and strap muscles
• C2-C4 -> Neck skin

Question 16

Where is the sympathetic chain found in the neck? What is its function?

Answer 16

• In the prevertebral fascia
• Involves sympathetic fibres from T1-T6
• Forms superior, middle and inferior cervical ganglia, which provide much of the sympathetic innervation to structures of the head, neck and mediastinum.