Osteology Flashcards
what is the neurocranium
part of the skull which encases and protects the brain
what is the viscerocranium
part of the skull which makes up the jaw and facial skeleton
what are the 3 depression in the neurocranium
anterior, middle and inferior cranial fossae
what are the layers of bone of the calvaria
trilaminar:
- outer table (compact bone)
- diploeic cavity (spongy bone)
- inner table (compact bone)
what is the calvaria
skull cap
what are sutures
points are which the skull bones fuse together
why are sutures serrated
to prevent slippage
what are fontanelles
membranous areas of infant skull which are yet to ossify
when do the anterior fontanelles ossify
at 18months-2years
when do the posterior fontanelles ossify
at 1-3months
what is craniosyntosis
early fusion of the fontalles which impedes brain development and changes the shape of the skull
what is the purpose of fontanelles
to allow for skull size and shape to change
by which method do the bones on top of the skull develop
intramembranous ossification
by which method do the bones of the floor of the skull develop
endochondrial ossification
what is a cephalohaematoma
a bleed between the periosteum and the bone
true or false: there are inter cranial pressure changes with a cephalohaematoma
false - the blood can’t pass over suture lines as the periosteum is tightly adhered here so only covers that area of bone
what are the 2 main fractures of the skull
linear and depressed
what is a linear fracture
a fracture all the way through the bone with no bone displacement
what is a depressed fracture
where there is displacement of the bone towards the brain
what is a basilar skull fracture
fractures involving the cranial base
what are the signs associated with a basilar skull fracture
racoon eyes, bruising at the mastoid process, CSF through nose and ears
what is the pterion
the thinest part of the skull
what blood vessel is found behind the pterion
anterior branch of the middle meningeal artery
if there is a fracture at the pterion what type of haematoma would result
an extra dural haematoma - as the vessel is in the dura so blood would collect between the dura and bone
