osteology and cervical vertebre Flashcards
identify the osteological features/foramina of the typical and atypical cervical vertebrae
(which is atypic, typical?)
3rd–6th >> “typical” cervical vertebrae;
1st, 2nd, and 7th>> “atypical.”
which is the strongest cervical vertebrae?
AXIS
cuz atlas, carrying th eskull, rotates on it!
what stabilzes the Atlanto-axial joint?
What structure passes through the foramina in the transverse processes of the cervical vertebrae?
They give passage to the vertebral artery, vein and sympathetic nerves.
The cervical vertebrae have 3 features which distinguish them from thoracic vertebrae:
vertebral foramen get _____as we go down the cervical vertebrae
SMALLER
describe shape of atlas
a ring-like, kidney-shaped bone lacking a spinous process or body
consisting of 2 lateral masses connected by anterior and posterior arches.
Its concave superior articular facets receive the occipital condyles.
name joints unique to Cervical Spine
- -atlanto-axial
- -atlanto-occipital
why does the cervical vertebrae can dislocate or “slip-off” at much less force than is required for them to fracture?
The articular surfaces of the cervical vertebrae are more horizontally orientated than in other vertebrae
would a Slight dislocation damage the spinal cord in the cervical region? why?
Slight dislocation may not damage the spinal cord because of the large vertebral canal in the cervical region.
where r the most common sites of cervical spine injuries?
C2, C6, C7
where do the most severe (fatal) injuries occur? why
upper part of spine, C1-C4
where damage can lead to quadriplegia and cessation of respiratory movements.
How might an anterior view of C1 and C2 be obtained?
How many bones does the skull have?
The skull is a collective term referring to the complete skeleton of the head,
which includes the cranium and mandible.
divisions of Cranium & key feautres of each
What is the difference between the “viscerocranium” and the “neurocranium”?
difference btw a hole and a fissure in the skull?
roundish>> hole
narrow slit>> fissure
what does the neurocranium consist of?
bones of the neurocranium
what is the thinnest part of the calvaria?
what is a suture? what is its function? structure?
immobile, fibrous Joints btw bones,
the interlocking btw the bones make sit hard for bones to dislocate!
As we age, these suture lines begin to ossify.
what r the sutures of the calvaria?
coronal, sagittal and lambdoid)
now we move on to cranial floor, describe it!
shade the anterior middle and posterior fossa
how do u know which ones which?
Anterior> lesser wing of sphenoid bone
middle> petrous part of temporal bone
Posterior> other part of petrous bone
What are the fontanelles and why is their presence important in the fetal/infant skull
Sutures, which are soft but tough membranous connections, lie in the junctions where there is incomplete fusion of the bones.
At what age do the anterior and posterior fontanelles fuse?
The anterior fontanelle> closed By ~18 months – 2 years> becomes the site of the bregma.
The posterior fontanelle> closes within first 2 -3 months> becomes site of the lambda.
Fontanelles are therefore only an anatomical feature of the fetal/ infant skull.
how do the sutures appear on a CT scan?
chna fracture!
what r the types of skull fractures?
2 main fracture types:
– Linear pass full thickness of skull, fairly straight, involve
no bone displacement
– Depressed: fragment is displaced inwards towards the brain
Fractures involving the cranial base = basilar skull fractures
most common facial fractures include? (4)
Fractures of the nasal bones (cuz of the prominence of the nose), zygomatic bone and arch and mandible are common
what is the cheek bone? what does it articulate w/?
zygomatic bone!
they inferolateral sides of the orbit articulate with the frontal, sphenoid, temporal bones and the maxillae.
ok.. moving on to the viserocranium
how many bones and name them!
is formed by bones enclosing the orbits, nasal cavity, oral cavity, paranasal sinuses and includes the maxillae (the upper jaw) and the mandible (the lower jaw); the jaws house the teeth.
just above the orbital margin is a sharp bony ridge called________.
what is the significance of this area?
the supraciliary arc
The skin overlying this area can be easily split when there is a blunt force in jury to this area of the head.
why is the mandible movable?
becauseitarticulateswiththecranial base at the temporomandibular joint (TMJ),
Xray
Xray sinus
Where is the vomer bone?
A boner is in the middle. (So the vomer) is in the middke forming nasal septum!
Explain the ethmoid bone in all views of the skull?
Label the
zygoma and zygomatic arch
paranasal sinuses - frontal, nasal/ethmoid, and maxillary
Describe the process that leads to the fusion of the fontanelles (i.e. how do they become ossified).
in the adult skull what is the anatomical point to the site of the anterior & posterior fontanelle in the infant skull?
