Skull

Question 1

What two groups is the skull divided into?

Answer 1

Neurocranium and viscerocranium

Question 2

How many bones are in the neurocranium?

Answer 2

8

Question 3

How many bones are in the viscerocranium?

Answer 3

12

Question 4

What does the neurocranium do?

Answer 4

Encase the brain

Question 5

What does the viscerocranium do?

Answer 5

Make up the facial skeleton and jaw

Question 6

What are the 3 parts of the neurocranium?

Answer 6

Calvaria (skull cap)
Cranial floor
Cranial cavity

Question 7

How does the skull cap ossify?

Answer 7

Begins as a membrane so inter-membranous ossification

Question 8

How does the floor and base of the skull develop?

Answer 8

Begins as cartilage so endochondrial ossification

Question 9

What does the viscerocranium surround?

Answer 9

Oral cavity, pharynx and upper respiratory passages

Question 10

What does the viscerocranium develop from?

Answer 10

Pharyngeal arches

Question 11

How many bones are there in the skull?

Answer 11

22

Question 12

What is a fossae?

Answer 12

Shallow depression or hollow

Question 13

What is a canal?

Answer 13

A bony tunnel

Question 14

What is a foramina?

Answer 14

Round hole

Question 15

What is a fissure?

Answer 15

Narrow slit hole

Question 16

Why does the cranial floor need holes?

Answer 16

So cranial nerves and blood vessels can get to and from the brain

Question 17

What are the three bowl shapes depressions in the cranial floor called?

Answer 17

Anterior, middle and posterior cranial fossae

Question 18

What is the arrangement of calvaria bone and why?

Answer 18

Trilaminar

Protective strength without adding much weight

Question 19

What are the three layers of the calvaria?

Answer 19

Outer table-hard bone
Diploeic cavity- spongy bone
Inner table

Question 20

What are sutures?

Answer 20

Intersections between bones of the skull

Fibrous joints

Question 21

Why are sutures serrated?

Answer 21

To prevent slippage and movement

Question 22

When does suture lines stop growing?

Answer 22

Puberty

Question 23

How are suture lines obliterated?

Answer 23

Gradually from inside to outside

Question 24

What cannot pass through suture lines?

Answer 24

Cephalohaematoma

Question 25

What do infant skulls have that adults do not?

Answer 25

Fontanelles

Large areas of unossified membranous gaps between bones

Question 26

What do fontanelles allow?

Answer 26

Alteration of skull in child birth

Permits growth of the brain

Question 27

When do anterior fontanelles fuse?

Answer 27

18months- 2 years

Question 28

What can you tell from anterior fontanelles?

Answer 28

Healthy if convex

Can tell inter-cranial pressure and hydration from palpation

Question 29

What is early fusion of fontanelles called?

Answer 29

Craniosyntosis

Question 30

When do posterior fontanelles fuse?

Answer 30

1-3months

Question 31

What is the biggest concern with a skull fracture?

Answer 31

Intercranial injury

Question 32

If a intercranial injury is suspected what would you do?

Answer 32

CT scan

Question 33

What is linear displacement of the skull?

Answer 33

No bone displacement

Question 34

What is depressed displacement of the skull?

Answer 34

Fragment displaced towards brain

Question 35

What is the issue with cranial base fractures?

Answer 35

Cranial nerve injuries

Cerebrospinal fluid leaks

Question 36

What is the pterion and what is the issue with it?

Answer 36

Thinnest area of skull where suture lines meet

Middle meningeal artery lies beneath so can cause intercranial haemorrhage if fractures

Question 37

What will basilar skull fractures cause?

Answer 37

Black eyes

Bruises behind the ear

Question 38

Where are common sites of facial fractures?

Answer 38

Nasal
Zygomatic bone and arch
Mandible