3.1 Skull osteology

Question 1

frontal bone starts as a pair then fuses. try or false?

Answer 1

true

Question 2

metric suture

Answer 2

failure of frontal pair of bones to fuse

Question 3

which portion of the temporal bone is within the calvaria?

Answer 3

squamous

Question 4

the anterior and posterior fontanelles form which structures?

Answer 4

bregma and lambda

Question 5

treatment of severe craniosynostosis

Answer 5

break the ossified joint so normal growth can occur

Question 6

name of arteries that run through dipole of skull

Answer 6

diploic

Question 7

what coats the inner lining of skull bone?

Answer 7

periosteum (aka periosteal layer of dura mater)

Question 8

which bones form the anterior cranial floor?

Answer 8

-frontal
-ethmoid
-greater wing of sphenoid bone

Question 9

importance of crista Galli

Answer 9

attaches to falx cerebri

Question 10

importance of cribriform foramina

Answer 10

passage of olfactory nerves to roof of nasal cavity

Question 11

importance of perpendicular plate

Answer 11

forms nasal septa

Question 12

the ethmoid bone is pneumatised. what does this mean?

Answer 12

air filled cavities called paranasal air sinuses

Question 13

relation of sella turcica and pituitary gland

Answer 13

pituitary gland sits in pituitary fossa of sella turcica

Question 14

lesser wings of sphenoid bone form what?

Answer 14

posterior part of anterior cranial fossa

Question 15

role of petrous part of temporal bone

Answer 15

houses middle and inner ear structures
-anterior semicircular canal
-cochlea
-vestibulocochlear nerve
-posterior semicircular canal
-ear canal

Question 16

superior nuchal line of occipital bone function

Answer 16

attachment for trapezius muscle

Question 17

at what point does the brainstem continue as spinal cord?

Answer 17

foramen magnum

Question 18

types of skull fracture

Answer 18

-linear
-comminuted
-depressed
-non depressed

Question 19

which part of skull base is fractured to give signs…
-periorbital ecchymoses

-CSF ottorhea
-CSF rhinorrhea
-battles sign
-blood behind eardrum

Answer 19

-anterior cranial fossa- orbital plate fracture

-petrous bone in middle cranial fossa

Question 20

CSF rhinorrhea

Answer 20

clear fluid dripping from nose with head injury= CSF

Question 21

imaging choice for facial injuries/fractures. why?

Answer 21

plain xray- not as much concern for brain, neuromuscular structures underneath

Question 22

sign of supraorbital ridge fractures

Answer 22

slice through eyebrow

Question 23

are maxilla fractures rare and uncomplicated?

Answer 23

rare
but could fall backwards to occlude airway

Question 24

best view for suspected
-zygoma fracture
-maxilla fracture

Answer 24

-bucket handle view
-OPG (pan across, usually 2 fractures)

Question 25

what is the TMJ?

Answer 25

articulation between mandibular fossa of temporal bone and condyle of mandible

Question 26

what type of joint is TMJ?

Answer 26

synovial hinge type -lined with fibrocartilage -fibrocartilaginous disc

Question 27

nerve supply to TMJ

Answer 27

auriculotemporal nerve (sensory, branch of mandibular division of trigeminal)

Question 28

pain location in TMJ pathology?

Answer 28

can radiate to side of head, jaw

Question 29

importance of coronoid process

Answer 29

temporalis muscle insertion

Question 30

what stabilises the TMJ?

Answer 30

joint capsule + 3 extracapsular ligaments

Question 31

2 movements of TMJ, and what produces the movement?

Answer 31

rotation: inferior joint capsule gliding: superior joint capsule (retraction, protraction)

Question 32

dislocation of TMJ

Answer 32

condyle of mandible passes anteriorly in front of articular tubercle, jaw locks open and muscles of mastication keep joint locked

Question 33

reduction technique for TMJ dislocation

Answer 33

strength, push down of jaw to relax muscles of mastication then slide back into mandibular fossa

Question 34

label 1.6 of GW page 42

Answer 34

-

Question 35

what do the following transmit? -superior orbital fissure -optic canal -foramen rotundum -foramen ovale -foramen lacerum -foramen spinous -carotid canal

Answer 35

-nerves -optic nerve -maxillary trigeminal nerve -mandibular trigeminal nerve -filled with cartilage, ICA over top -middle meningeal artery -ICA

Question 36

peaked ridge of petrous part of temporal bone forms what?

Answer 36

boundary between middle and posterior cranial fossa

Question 37

nerve carrying sense of hearing and balance arises from where? exits through where?

Answer 37

arises from petrous part of temporal bone exits via internal auditory meatus to brainstem

Question 38

facial nerve exits skull where?

Answer 38

stylomastoid foramen

Question 39

which blood vessel begins on exiting jugular foramen of skull?

Answer 39

IJV

Question 40

why do frontal and maxilla bones look black on X-ray?

Answer 40

paranasal sinuses- contain air

Question 41

name 3 extra cranial fossa

Answer 41

1. temporal 2. infra temporal 3. pterygopalatine