2) Osteology and Radiology

Question 1

What can the cranium be split up into?

Answer 1

Neurocranium - housing brain

Viscerocranium - facial skeleton

Question 2

What does the neurocranium consist of?

Answer 2

Calvaria (roof) and base of skull

Question 3

What bones form the calvarium?

Answer 3

Frontal, occipital and two parietal bones

Question 4

What bones form the cranial base?

Answer 4

Frontal, sphenoid, ethmoid, occipital, parietal and temporal bones

Question 5

How are the bones of the calvaria arranged?

And why?

Answer 5

Tri lamina arrangement, two layers of compact bone separated by layer of spongy bone (diploe)
Conveys strength without adding significant weight

Question 6

Give examples of bones in the facial skeleton:

Answer 6

Zygomatic, maxilla, mandible,. lacrimal, nasal, sphenoid, vomer and palatine bone

Question 7

What are the two types of joint in the skull?

Give an example of each

Answer 7

Immobile: joined by fibrous tissue e.g. sutures
Mobile: only one, temporomandibular joint

Question 8

Give examples of sutures in the skull:

Answer 8

Coronal: between parietal and frontal
Squamous: temporal and parietal
Sagittal: between parietal bones
Lambdoid: between parital and occipital

Question 9

What happens to the sutures as we age?

Answer 9

Ossify

Question 10

What are fontanelles?

Answer 10

Membranous areas of unfused skull in babies

Question 11

What is the function of fontanelles?

Answer 11

Allow for brain growth and flexibility eases passage through birth canal

Question 12

What are the names of the fused anterior and posterior fontanelles?

Answer 12

Bregma

Lambda

Question 13

What is the significance of sunken fontanelles?

Answer 13

Dehydration or malnutrition

Question 14

What is the significance of bulging fontanelles?

Answer 14

Raised intracranial pressure or meningitis

Question 15

What is the significance of enlarged fontanelles?

Answer 15

Premature birth or Down’s syndrome

Question 16

What is the pterion?

Answer 16

Lateral aspect of skull where temporal, parietal, frontal and sphenoid bones meet. Thinnest part of skull

Question 17

What can a fracture at the pterion lead to?

Answer 17

Injury of anterior branch of middle meningeal artery causing extradural haematoma

Question 18

Why is it called an extradural haematoma?

Answer 18

Blood vessels run between periosteum and dura mater so dura is pushed away from bone by blood and pressure exerted on brain

Question 19

What are the 3 areas of the cranial floor?

Answer 19

Anterior, middle and posterior floor

Question 20

What allows neurovascular structures to pass into cranial compartment?

Answer 20

Foramina of cranial floor

Question 21

What causes skull fractures?

Answer 21

Severe trauma, blows/impact injury

Question 22

What are the consequences of skull fractures?

Answer 22

Damage underlying brain, blood vessels or cause intracranial haematoma

Question 23

What is the primary investigation used in suspected skull fractures?

Answer 23

CT scan

Question 24

What causes basilar skull fractures?

Answer 24

Force transmitted through vertebral column

Question 25

What suggestive signs of a basilar skull fracture?

Answer 25

Battle's sign - bruising of mastoid process Raccoon eyes - bilateral bruising around eyes Haemotympanum - blood behind ear drum CSF leakage from nose and ear

Question 26

What are the complications of basilar skull fractures?

Answer 26

Meningeal tears Cranial nerve palsies Meningitis

Question 27

What causes facial skeleton fractures?

Answer 27

Road traffic collisions, fights and falls

Question 28

What bones of the facial skeleton are commonly fractured?

Answer 28

Nasal, zygomatic and mandible

Question 29

If a patient has a suspected neck injury, what should be done?

Answer 29

Spinal immobilisation

Question 30

What investigations can confirm a spinal fracture in adults and children?

Answer 30

CT in adult | X-ray/MRI in children

Question 31

What is a Jefferson's fracture and what causes it?

Answer 31

Burst fracture of C1, combination of anterior and posterior arch fractures. Caused by axial compression

Question 32

What is a Hangman's fracture and what causes it?

Answer 32

Bilateral fracture of posterior arch of C2 and disruption of C2/3 junction. Caused by hyperextension of neck

Question 33

What are the complications of Hangman's fractures?

Answer 33

May extend to transverse foramen and damage vertebral arteries C2 may displace causing spinal cord damage

Question 34

What are vertebral crush fractures and what causes them?

Answer 34

Fractures of vertebral bodies causes by osteoporosis, hyperflexion and various others

Question 35

What degenerative disease can affect the spine?

Answer 35

Osteoarthritis -> cervical spondylosis

Question 36

What are the features of cervical spondylosis?

Answer 36

``` Osteophytes Facet joint hypertrophy Disc herniation Disc space narrowing Sclerosis of end plates ```

Question 37

What is cervical spondylotic radiculopathy and what can it lead to?

Answer 37

Nerve root impingement | Dermatomal arm pain +/- mild weakness and sensory loss

Question 38

What is cervical spondylotic myelopathy and what can it lead to?

Answer 38

Spinal cord compression | Loss of function and fine motor skills in upper limb