1.1 General Organisation of the Head and Neck

Question 1

What two parts make up the cranium?

Answer 1

Neurocranium- surrounds and protects brain

Viscerocranium- forms the face

Question 2

What are the joints between bones in the skull called?

Answer 2

Sutures- specialised fibrous joints

Question 3

What are the two main nerves of the face?

Answer 3

Facial Nerve
Trigeminal Nerve

Question 4

What does the facial nerve supply?

Answer 4

Supplies muscles of facial expression

Question 5

What does the trigeminal nerve supply?

Answer 5

Sensory innervation to face and motor to muscles of mastication

Question 6

What are the blood vessels supplying the face?

Answer 6

Facial artery
Facial vein

Question 7

What types of muscles are muscles of facial expression?

Answer 7

Dilators/ sphincters
Attach to bone, skin/fascia of the face and other muscles

Supplied by Facial nerve CNVII

Question 8

What do muscles of mastication act on?

Answer 8

Act on the temporomandibular joint
Open or close the jaw, bone-to-bone attachments
Supplied by the trigeminal nerve, mandibular branch

Question 9

What bones do muscles of facial expression attach to?

Answer 9

Frontal bone
Zygoma/Zygomatic arch
Maxilla
Mandible

Question 10

Label the image

Answer 10

Question 11

What is the structure of occipitofrontalis?

Answer 11

Two muscle bellies, frontal and occipital, joined by broad flat connective tissue sheet epicranial aponeurosis

Question 12

What is the function of the occipitofrontalis muscle?

Answer 12

Raises the eyesbrows and wrinkles skin of forehead

Can test facial nerve by testing this movement

Question 13

What is the structure of orbicularis oculi?

Answer 13

One muscle circling around each eye orbit

Flat, constrictor muscle

Question 14

What are the two parts of the orbicularis oculi?

Answer 14

Orbital
-squeezes eyelids together tightly

Palpebral
-gently closes eyelid (involuntary blinking)

Question 15

What is the critical role of the orbicularis oculi?

Answer 15

Protects the eye
Keeps front of eye moist (tear film)

Question 16

What is the function of orbicularis oris?

Answer 16

Purses lip together- contributes to facial expressions and speech

Seals mouth closed- helps keep food/fluid inside oral cavity

Question 17

Describe the structure of the orbicularis oris

Answer 17

One muscle surrounding orifice of mouth

Flat, constrictor muscle & forms majority of lips

Arises from maxilla and mandible, inserts into skin and membrane of lips

Question 18

What is the function of the buccinator?

Answer 18

Holds cheek taut to prevent food from collecting between teeth and cheek

Contract buccinator to expel air against pursed lips, playing trumpet

Question 19

What is the structure of the buccinator?

Answer 19

Flat, thin muscle forming wall of cheek

Question 20

What are the dilators of the mouth?

Answer 20

Risorius
Zygomaticus major (teeth smile)

Draw angles of the mouth superiorly and posteriorly to smile

Question 21

What is the platysma?

Answer 21

Muscle of facial expression, runs very superficially in neck, immediately beneath the skin

Question 22

What is the structure of the platysma?

Answer 22

Thin-sheet like muscle
Arises from fascia overlying anterior chest
Inserts onto mandible

Tenses the skin, makes you grimace

Aids in depression if the mandible

Question 23

What innervates muscles of facial expression?

Answer 23

Extracranial branches of facial nerve

Question 24

Label the image

Answer 24

To Zanzibar By Motor Car

Question 25

How are branches of the facial nerve named?

Answer 25

In accordance with region going to supply Close relationship to parotid gland (not supplied by facial, glossopharyngeal, facial does all other salivary glands)

Question 26

What is the route of the facial nerve?

Answer 26

1. Pons 2. Enters petrous bone via internal accoustic meatus 3. Exits skull by Stylomastoid foramen 4. Runs through Parotid gland 5. Branches into facial expression muscles

Question 27

What can cause damage to the facial nerve?

Answer 27

Parotid gland pathology -Malignancy -Surgery Can cause ipsilateral paralysis of facial muscles

Question 28

What is the commonest cause of Facial nerve lesions?

Answer 28

Bell's palsy Rule everything else out first, idiopathic but presumed to be infective aetiology

Question 29

What is Bell's palsy?

Answer 29

Most common non-traumatic cause of ipsilateral facial paralysis Due to inflammation of the facial nerve, inflammation causes oedema and compression of the nerve as it leaves the skull

Question 30

How do facial nerve lesions present?

Answer 30

Ipsilateral facial muscle weakness or paralysis

Question 31

How does parotid cancer present?

Answer 31

- Weakness of facial muscles on one side with ipsilateral enlargement of the parotid gland. - Weakness due to infiltration of cancer into parotid gland - Benign parotid pathology (e.g mumps) usually has no facial weakness as nerve not involved

Question 32

What scale can be used to indicate facial nerve palsy severity?

Answer 32

House-Brackmann Scale

Question 33

What are the different branches of the trigeminal nerve?

Answer 33

Va- Opthalmic Vb- Maxillary Vc- Mandibular

Question 34

What branch of the trigeminal nerve also has motor function?

Answer 34

Vc- Mandibular branch

Question 35

What are the muscles of mastication?

Answer 35

Temporalis Masseter Medial and Lateral Pterygoids

Question 36

What is the function of the temporalis?

Answer 36

**Elevates** and posterior fibres **retract** mandible Close mouth and pull back

Question 37

What is the function of the masseter?

Answer 37

Strong **elevator** and **protacts** mandible

Question 38

What is the function of the medial pterygoid?

Answer 38

Elevates the mandible, act together with lateral pterygoid to move jaw side to side Close the mouth

Question 39

What is the function of the lateral pterygoid?

Answer 39

Depresses mandible opens jaw Acts with medial pterygoid to move jaw side to side think laaaaaaaaaaaaaaaaaaaaaaa