General Organisation of the Head and Neck.

Question 1

Which Nerve is the Muscles of Facial Expression Innervated by?

Answer 1

Facial Nerve (Cranial Nerve VII).

Question 2

Which Nerve is the Muscles of Mastication Innervated by?

Answer 2

Trigeminal Nerve (Cranial Nerve V)- Mandibular Nerve.

Question 3

What is the Nerve Innervation of Levator Palpebrae Superioris?

Answer 3

Oculomotor Nerve.

Question 4

What is the Action of Levator Palpebrae Superioris?

Answer 4

Elevates the superior eyelid.

Question 5

What is the Action of Occipitofrontalis (Facial Nerve)?

Answer 5

Raises the eyebrows. Made up of frontal, occipital and cranial aponeurosis.

Question 6

What is the Action of Orbicularis Oculi (Facial Nerve)?

Answer 6

Close eyelids, close eyelids tightly and drain tears.

Question 7

What is the Action of Orbicularis Oris (Facial Nerve)?

Answer 7

Close lips.

Question 8

What is the Action of Buccinator (Facial Nerve)?

Answer 8

Pull cheek inwards against teeth.

Question 9

What is the Action of Platysma (Facial Nerve)?

Answer 9

Depress angle of mouth.

Question 10

What is the Action of Dilator Muscles of the Lips (Facial Nerve)?

Answer 10

Open mouth.

Question 11

Name the 4 Muscles of Mastication.

Answer 11

1. Masseter.
2. Temporalis.
3. Medial Pterygoid.
4. Lateral Pterygoid.

Question 12

What is the Action of Masseter (Trigeminal Nerve)?

Answer 12

Elevates the mandible, closing the mouth (main).

Question 13

What is the Action of Temporalis (Trigeminal Nerve)?

Answer 13

Elevates the mandible, closing the mouth.

Question 14

What is the Action of the Medial Pterygoid (Trigeminal Nerve)?

Answer 14

Elevates the mandible, closing the mouth.

Question 15

What is the Action of the Lateral Pterygoid (Trigeminal Nerve)?

Answer 15

Moves the jaw side to side, protract the mandible, help the suprahyoids to depress the mandible and open the mouth.

Question 16

What is the Action of the Suprahyoids (Mandibular Nerve)?

Answer 16

Depress the mandible, opening the mouth.

Question 17

What is the Nerve Innervation of Sternocleidomastoid?

Answer 17

Accessory Nerve.

Question 18

What is the Action of Sternocleidomastoid?

Answer 18

Flexing the head and neck.

Question 19

What is the Nerve Innervation of Trapezius?

Answer 19

Accessory Nerve.

Question 20

What is the Action of Trapezius?

Answer 20

Shrug the shoulders, retract the scapula and pull it inferior as well as elevating the scapula.

Question 21

Describe the Borders of the Anterior Triangle of the Neck.

Answer 21

Superiorly: inferior mandible.
Laterally: anterior sternocleidomastoid.
Medially: sagittal midline of neck.
Roof: investing fascia.
Floor: visceral fascia.

Question 22

Describe the Contents of the Anterior Triangle of the Neck.

Answer 22

1. Suprahyoid Muscles.
2. Infrahyoid Muscles.
3. Common Carotid Artery.
4. Internal Jugular Vein.
5. Facial Nerve (VII).
6. Glossopharyngeal Nerve (IV).
7. Vagus (X) Nerve.
8. Accessory (XI) Nerve.
9. Hypoglossal (XII) Nerve.

Question 23

Describe the Borders of the Carotid Triangle.

Answer 23

Superiorly: posterior belly of diagastric muscle.
Laterally: medial sternocleidomastoid.
Inferiorly: superior belly of omohyoid.

Question 24

Describe the Contents of the Carotid Triangle.

Answer 24

Found within the Anterior Triangle and thus contains some of the same contents:

1. Common Carotid Artery.
2. Internal Jugular Vein.
3. Hypoglossal (XII) Nerve.
4. Vagus (X) Nerve.

Question 25

Describe the Borders of the Posterior Triangle of the Neck.

Answer 25

Anteriorly: posterior sternocleidomastoid. Posteriorly: anterior trapezius. Inferiorly: middle 1/3 of clavicle. Roof: investing fascia. Floor: Prevertebral fascia and scalene muscles.

Question 26

Describe the Contents of the Posterior Triangle of the Neck.

Answer 26

1. Omohyoid muscle. 2. Scalene muscles. 3. Splenius Capitis. 4. Levator Scapulae. 5. External Jugular Vein. 6. Transverse Cervical, Subclavian and Suprascapular Veins. 7. Transverse Cervical, Subclavian and Suprascapular Arteries. 8. Accessory Nerve. 9. Cervical Plexus (floor). 10. Brachial Plexus.

Question 27

Describe the Investing Fascia Layer of the Neck.

Answer 27

Most superficial layer of deep fascia. Surrounds the entire neck. Superior margin- mandible, mated process, nuchal line and occipital protuberance. Posteriorly: spinous process and ligaments nuchae. Inferiorly: manubrium, clavicle, acromion and spine of scapula. Encloses all neck structures and separates sternocleidomastoid, trapezius and submandibular and parotid salivary glands. Forms the roof of the posterior and anterior triangles of the neck.

Question 28

Describe the Pretracheal Fascia Layer of the Neck.

Answer 28

Thin anterior and lateral area of neck. Attached to the hyoid bone superiorly and anteriorly and inferiorly extends into thorax, blending with the fibrous pericardium. Thus when swallowing thyroid and larynx move up. Consists of a muscular layer enclosing infra hyoid muscles and visceral layer enclosing the thyroid, trachea and oesophagus. Posteriorly blends with the buccopharyngeal fascia.

Question 29

Describe the Buccopharyngeal Fascia Layer of the Neck.

Answer 29

Blended from the pretracheal fascia. It is associated with the pharynx and oesophagus. It runs from the base of the skull superiorly to the diaphragm inferiorly.

Question 30

Describe the Carotid Sheath.

Answer 30

Tubular, fibrous structure that extends from skull through the root of the neck to the arch of aorta. Within it is the Common Carotid Artery, Internal Jugular Vein, Cranial Nerve and the Vagus Nerve.

Question 31

Describe the Prevertebral Fascia Layer of the Neck.

Answer 31

Sheath for the vertebral column and muscles. From the base of the cranium to the 3rd thoracic vertebra. Extends laterally as axillary sheath to surround axillary vessels and brachial plexus. Forms the floor of the posterior triangle of the neck.

Question 32

Clinical Relevance of the Deep Cervical Fascia.

Answer 32

They form a natural cleavage plane to allow easy passage over. This makes it easier in surgery and also determines the direction of infection spread.

Question 33

Describe the Retropharyngeal Space.

Answer 33

Lies between the prevertebral layer of fascia and the buccopharyngeal fascia. 3-4 years the superior part has lymph nodes to drain the nose, oral cavity and upper pharynx. Allows the pharynx to move freely on the vertebral column and expand during swallowing. Infections can spread to the mediastinum (mediastinitis).

Question 34

What is the sign and symptoms of a Retropharyngeal Abscess?

Answer 34

Visible bulge, sore throat, difficulty swallowing, stridor, reluctance to move neck at high temperature.