H&N1 - General Organisation of the Head & Neck

Question 1

What are the 5 key extracranial branches of the facial nerve (CNVII)?

(To Zanzibar By Motor Car)

Answer 1

Temporal, Zygomatic, Buccal, Marginal Mandibular, Cervical

Question 2

What are the 3 key branches of the trigeminal nerve (CNV) and where do they cover?

Answer 2

Opthalmic (Va) - forehead, eyes, top of nose
Maxillary (Vb) - cheek, corner of eyes
Mandibular (Vc) - jaw, temple, ear flap

Question 3

Which 3 muscles of mastication elevates the mandible (closes jaw)?

Answer 3

Masseter
Temporalis - posterior fibres also retracts the jaw
Medial Pterygoid - also protrudes the jaw

Question 4

Which 3 muscles of mastication depresses the mandible (opens jaw)

Answer 4

Lateral Pterygoid
Platysma
Suprahyoids

Question 5

Which 2 muscles of facial expression are used to smile?

dilator muscles of lips

Answer 5

Zygomaticus (major & minor)

Risorius

Question 6

What are the 6 muscles of facial expression?

not including the smile ones

Answer 6

Occipitofrontalis - elevates eyebrows, wrinkles forehead
Orbicularis Oculi - closes the eye (palpebral = gentle, orbital = forceful)
Buccinator - compresses cheeks during mastication
Orbucularis Oris - purses lips (kissing)
Platysma - depresses angles of mouth, tenses neck skin
Trapezius - elevates shoulders, assists shoulder abduction (>90)

Question 7

Which 2 muscles are innervated by the spinal accessory nerve (CNXI)?

Answer 7

Sternocleidomastoid (SCM)

Trapezius

Question 8

What is Bell’s Palsy

Name 6 Symptoms

Answer 8

Damage to the facial nerve (often caused by trauma or inflammation)

1. ) Weak face on one side
2. ) Struggles to blink (orbicularis oculi)
3. ) Can’t raise eyebrows (occipitofrontalis)
4. ) One side can’t smile (zygomaticus, risorius)
5. ) Dry eyes (no blinking, lacrimal glands affected)
6. ) Can still open and close her jaw (trigeminal nerve not affected)

Question 9

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

What structures pass through it?

Answer 9

Superior - inferior border of the mandible
Lateral - medial/anterior border of SCM
Medial - sagittal line down the midline of the neck

Structures coursing between the head and thorax

Question 10

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

What structures pass through it?

Answer 10

Inferior - clavicle
Lateral - trapezius (anterior border)
Medial - SCM (posterior border)
Floor - scalenes

Structures coursing between the thorax/neck and upper limb

Question 11

What are the borders of the carotid triangle?

Answer 11

Superior - digastric (posterior belly)
Lateral - SCM
Medial - omohyoid (superior belly)

Question 12

Name 6 anatomical structures in the neck

Answer 12

Hyoid Bone
Thyroid Cartilage
Cricoid Cartilage
Thyroid Gland
Trachea
Common Carotid Artery

Question 13

2 features of the superficial cervical fascia layer

Answer 13

1. ) Loose connective tissue containing adipose

2. ) Contains anterior and external jugular veins, cutaneous nerves, superficial lymph nodes, platysma

Question 14

3 features of the pretracheal layer

Answer 14

1. ) extends into thorax, blending with fibrous pericardium
2. ) encloses infrahyoid muscles, thyroid gland, trachea, and oesophagus
3. ) posteriorly, becomes the buccopharyngeal fascia which covers the pharynx and oesophagus

Question 15

3 features of the investing layer

Answer 15

1. ) most superficial deep layer
2. ) attaches to the spinous process of the vertebrae and ligamentum nuchae
3. ) splits to enclose the SCM, trapezius, submandibular and parotid salivary glands

Question 16

3 features of the carotid sheath

Answer 16

1. ) tubular, fibrous structure
2. ) extends from the base of the skull to the aortic arch
3. ) contains the common carotid artery, internal jugular vein and the vagus nerve (CNX), and hypoglossal nerve

Question 17

3 features of the prevertebral layer

Answer 17

1. ) forms a sheath for the vertebral column and muscles associated with it
2. ) extends from base of the cranium to the 3rd thoracic vertebra
3. ) extends laterally as the axillary sheath which surrounds the axillary vessels and brachial plexus

Question 18

3 features of deep neck space infections

Answer 18

1. ) an infection or abscess can arise between fascial planes causing the space to become swollen
2. ) infective source often originates in teeth, pharynx, sinuses or middle ear
3. ) if in retropharyngeal space, the infection can spread into the thorax, causing mediastinitis

Question 19

What are the 3 blood vessels in the neck?

Answer 19

Common Carotid Artery (CCA) - splits into internal and external carotid
Internal Jugular Vein (IJV) - main vein, used to find blood pressure, receives venous drainage from the face
External Jugular Vein (EJV) - more superficial than IJV

Question 20

What are the 6 muscles of the neck?

Answer 20

Platysma
SCM
Trapezius
Scalenes - floor of the posterior triangle
Suprahyoids - elevate the hyoid bone and depress the mandible, contains digastric muscles
Infrahydoids - depress the hyoid bone to help stablise it, strap muscles, contains omohyoids