vertebral column, spinal cord Flashcards
what type of curvature is the thoracic spine and sacrum/coccyx?
primary
what type of curvature is the cervical and lumbar curves?
secondary
cruciate ligament function:
holds the dens in place during rotation of the head
looks like a cross in front of the dens
parts of the cross:
superior longitudinal band
transverse ligament of atlas band
inferior longitudinal band
apical ligament function:
deep to the cruciate ligament
attaches dens to the skull
alar ligaments function:
attaches the dens to the skull, laterally
what are the costal facets?
on the sides of the vertebrae, articulate with the ribs
thoracic region
zygapopphysial joints:
articulation between the superior and inferior facets
AKA facet joints
components of the vertebral disc:
annulus fibrosis
nucleus pulposus
layer of hyaline cartilage underneath
which foramen do the spinal nerves exit?
the intervertebral foramen
(visible on lateral view)
distinguishing factor of cervical vertebrae:
transverse foramina
(transmit the vertebral arteries)
bifid spinous process
distinguishing feature of thoracic vertebrae:
articular facets for ribs
very pointy spinous processes
spinous process points downwards
distinguishing feature of lumbar vertebrae:
looks like a moose:
blunted/rounded spinous process
where does the ligamentum nuchae attach?
occipital protuberance and the spinous process of C7
what does the ligamentum nuchae turn into when it passes the C7 attachment point?
supraspinous ligament
what are the 2 ligaments that cover the vertebral bodies?
anterior and posterior longitudinal ligaments
what ligament connects the spinous processes of stacked vertebrae?
interspinous ligament
what is a compression fracture?
when the vertebral is compressed or cracked as a result of an injury or disease (i.e. car crash, fall from heights, osteoporosis, or tuberculosis (Pott’s disease))
what happens to the dorsal end of the spinal cord during development?
spinal extends full length of spine at 8 weeks pre-natal
S1 spinal nerve protrudes but the spinal cord begins to retract upwards, leaving dural sac behind
newborn: conus medullaris is at L3, filum terminale is formed
adult: conus medullaris at L1, dural sac ends at S2
where does the filum terminale end?
coccyx
what is the lumbar cistern?
subarachnoid space in the lower lumbar canal
contains CSF and the nerve roots of the cauda equina
a space where spinal nerves continue to come out of their respective intervertebral foramina
what is contained in the epidural space?
spinal nerve roots, loose fatty tissue, small arteries, the internal vertebral venous plexus of Batson
at what spinal levels can the denticulate ligaments be found?
cranio-vertebral junction through T12
what do the pia and arachnoid matters originate from?
neural crest cells
leptomeninges
at which level are the gray and white rami (sympathetic fibers) located?
T1-L2
what level is a lumbar puncture taken from?
L3 and L4, near the level of the upper border of the iliac crest
what is the “popping” felt by the needle during a lumbar puncture?
when the dura is pierced
what are the layers (in order) that the needle pierces during a lumbar puncture)?
skin - ligament flavum - dura mater - arachnoid mater
needle enters the subarachnoid space (lumbar cistern) and extracts CSF
where can an epidural anesthetic needle be inserted?
trans-sacral epidural - through the sacral foramina
caudal epidural -inserted from underneath, up the bottom part of the space
what are the arteries of the spinal cord, what is the branching pattern?
descending thoracic aorta –> posterior intercostal –> spinal branch –> anterior and posterior spinal arteries
main vertebral vein plexuses?
anterior external vertebral venous plexus (in front of vertebral bodies)
anterior internal venous plexus
posterior internal venous plexus
posterior external vertebral venous plexus (laying on the spinous processes)
what is Batson’s plexus?
the anterior and posterior internal venous plexuses inside of the extra dural fatty space
what is the clinical downside of the vertebral veins?
the veins don’t have valves
therefore, CA in a lower level (i.e. prostate) can travel up and affect the cranial level (i.e. brain)
what happens during a herniated disc?
the annulus fibrosis bursts, the nucleus pulposus leaks out and compresses a nerve
this will affect the nerve BELOW the disk
e.g. L3/L4 disc herniation will compress the L4 nerve
purpose of a lumbar laminectomy
surgical exposure of the lower lumbar disc herniation
relieves some of the pressure on the pinched nerve/spinal cord
