Skull and Cranial cavity

Question 1

What are sutures?

Answer 1

fibrous joint of the skull. The ONLY place in the body that these will occur!

Question 2

What is the difference between an adult and baby skull?

Answer 2

Adults are fused, whereas babies have ‘fontanelles’, spaces where the babies skull is absent

Question 3

This is??

Answer 3

Anterior fontanelle of a newborns skull, 4x2.5cm

Should ossify around 18months

Question 4

The posterior circle is?

Answer 4

A posterior fontanelle, is smaller then the anterior, and ossifies earlier, around 6 months

Question 5

Is there a lateral fontanelle

Answer 5

yes but not that interesting as it ossifies too early.

Question 6

Fontanelles are ossified are replaced by?…

Answer 6

Sagittal, lamboid and coronal sutures which meet at a point

Anteriorally called ‘Bregma’

Posteriorally called’ Lambda

Question 7

Cranium is?

Answer 7

Bones from wherever the brain sits.

Question 8

This is?

Answer 8

Pterion.

Weakest (not thinnest) part of the skull. An area of sutures where 4 bones join together.

Question 9

Why is the Pterion clinically relevant?

Answer 9

Because the Middle Menangial artery (specifically the anterior branch) runs directly behind it! As this is the weakest part of the skull, so in the case of skull injury, then you can get ‘extradural haemmorrage’

Question 10

How do we identify the surface anatomy of the Pterion?

Answer 10

It is 2.5cm above the Zygomatic arch

2.5cm posterior to the lateral orbital margin

Question 11

Sinuses are?

Answer 11

Air filled spaces of the face. Babies do not have, develop by 14, babies don’t have the middle face.

Question 12

If infected, what will the sinus look like?

Answer 12

Sinusitis: are no longer clear on a scan

Question 13

WHat is this?

Answer 13

mandible. Know the parts!