H&N week 2- Triangles of neck.

Question 1

Label this diagram of the anterior triangle of the neck

Answer 1

Question 2

Label this diagram of the Posterior triangle of the neck

Answer 2

Question 3

What is the Platsyma?

Answer 3

A muscle that maintains tissue tone in the neck.

Question 4

What is the mylohyoid raphe?

Answer 4

A band of connective tissue.

Question 5

Discuss the relative locations of the mylohyoid muscle and the anterior belly of digastric.

Answer 5

The mylohyoid muscle is deeper than the anterior belly of digastric.

Question 6

Discuss the bifurcation of the common carotid artery?

Answer 6

It bifurcates into the external and internal carotid arteries at the level of the upper border of the thyroid cartilage.

Question 7

Compare the internal and external carotid artery?

Answer 7

External (slightly further forward & gives off branches) supplies blood to the face

Internal supplies blood to the brain.

Question 8

How is the external jugular vein formed and where?

Answer 8

Formed from the posterior division of the retromandibular vein and the posterior auricular vein near the angle of the mandible.

Question 9

Describe the heads of the sternocleidomastoid?

Answer 9

There are 2 heads of the sternocleidomastoid:

• Fleshy head that comes from the clavicle (starts as muscle)
• Head from the sternum starts off as a tendon and becomes muscle. (sTernal T for tendon)

Question 10

Where is the internal jugular vein found?

Answer 10

Deep to the sternocleidomastoid.

Question 11

What is the carotid sheath?

Answer 11

A sleve of fascia whcih contains:

Common carotid artery

Internal carotid artery.

Internal jugular vein.

Vagus nerve.

Question 12

What is the carotid sinus?

Answer 12

An area of the wall of the internal carotid artery which contains pressoreceptors or barroreceptors that monitor blood pressure.

Question 13

What nerves innervate the carotid sinus?

Answer 13

The glossopharyngeal nerve and the vagus nerve.

Question 14

What is the carotid body?

Answer 14

A small mass of chemoreceptors that monitor changes in oxygen and CO₂ concentration in the blood.

Question 15

What is the superior thyroid artery?

Answer 15

A branch of the external carotid artery that supplies the thyroid gland.

Question 16

What is the sternohyoid?

Answer 16

A muscle that connects the hyoid bone to the sternum

It is one of the strap muscles & the infrahyoid muscles.

Question 17

Where do you find the thyroid gland?

Answer 17

A gland located at vertebral levels C5-T1

Question 18

What does the thyroid gland produce?

Answer 18

T3 and T4 hormones.

Question 19

What is the sternothyroid?

Answer 19

A muscle found deep to the sternohyoid and attaches to the thyroid cartilage.

Question 20

What is the cricothyroid membrane

Answer 20

Also known as the cricothyroid ligament- this attaches along the inferior border of the thyroid cartilage and the superior border of the cricoid cartilage.

Question 21

What are the lamina of the thyroid cartilage?

Answer 21

The lamina are the sides of the thyroid cartilage.

Question 22

Compare the laryngeal prominences in males and females.

Answer 22

The laryngeal promience is more prominent in males than females (adam’s apple)

Question 23

Compare the submandibular and submental lymph nodes

Answer 23

Submandibular lymph nodes drain the area of the mouth/ nasal cavity and maxillary sinus.

Submental lymh nodes drain the most anterior parts of the lower part of the mouth (lower lip/skin on chin/ tip of the tongue and anterior teeth)

Question 24

What are the boundaries of the muscular triangle?

Answer 24

Medially- Median plane of the neck.

Superolaterally- Superior belly of the omohyoid muscle.

Inferiolaterally- anterior border of the sternocleidomastoid.

Question 25

What are the boundaries of the Carotid triangle?

Answer 25

Superiorly- posterior belly of digastric Inferiomedially- superior belly of omohyoid muscle Inferiolaterally- Anterior border of the sternocleidomastoid muscle.

Question 26

How can the anterior triangle of the neck be split further?

Answer 26

Into the: * Carotid triangle * Muscular triangle * Submandibular triangle * Submental triangle.

Question 27

What is the superior laryngeal nerve ?

Answer 27

This is a branch of the vagus nerve which passes through the thyrohyoid.

Question 28

Compare the two laryngeal nerves

Answer 28

Recurrent laryngeal nerve- innervates the larynx (vocal folds/ inferior constrictor/ posterior crico-arytenoid musles) Superior laryngeal nerve innervates cricothyroid muscle (external branch) & provides sensory fibres to the larynx mucosa (inner branch).

Question 29

What is the posterior triangle?

Answer 29

Everything behind the sternocleidomastoid.

Question 30

What is the accessory nerve and what is it's function?

Answer 30

This is cranial nerve 11. It supplies the trapezium and sternocleidomastoid muscles

Question 31

Describe the path of the accessory nerve?

Answer 31

The accessory nerve exits the skull via the jugular foramen and goes deep into the deep surface of the trapezius.

Question 32

What is the function of the trapezius?

Answer 32

It is for shrugging your shoulders.

Question 33

What is the scalenus medius?

Answer 33

A muscle going from the cervical vertibrae to the first rib.

Question 34

Compare the superficial cervical nodes and the supraclavicular nodes

Answer 34

The superficial cervical nodes drain the area of skin over the posteiror triangle. The supraclavicular nodes are lymph nodes found just above the the clavicle that drain the chest.

Question 35

What is the brachial plexus?

Answer 35

A large bundle of nerve fibres which are formed from C5-T1 spinal nerves. These go down into the axilla(armpit) to supply the upper limb.

Question 36

Name the three large bundles of the brachial plexus?

Answer 36

Superior, middle and inferior trunks.

Question 37

What is the Ansa Cervicalis?

Answer 37

A loop of nerve fibres from the anterior ramus of C1 spinal nerve which give nerve supply to the strap muscles. It is formed by the cervical nerves 1-3

Question 38

Where is the phrenic nerve found?

Answer 38

On the surface of the scalenous anterior muscle running between the cervical vertibrae and the first rib.

Question 39

What is the transverse cervical nerve?

Answer 39

This is a nerve formed from C2 and C3 spinal nerves that supplies the skin of the front of the neck.

Question 40

Describe the pathway of the transverse cervical nerve?

Answer 40

This comes behind the external jugular vein and transversley across the sternocleidomastoid to the anterior triangle.

Question 41

What is the great auricular nerve?

Answer 41

This is a big nerve formed by the re-arrangement of C2 and C3 spinal nerve fibres which supplies sensory supply to the area at the angle of the mandible parotid gland and ear.