Flashcards in 02 Lumbar Spine 2 Deck (33):
- spinal cord terminates at T12-L1
- cauda equina is below L1
below L1, any nerve injury is
direction of lumbar disc herniations
almost always posterolateral
herniation through the PLL (directly posterior) is called _______ and can impact _________
- central herniation
- impacts cauda equina
- 5th lumbar vertebrae takes on characteristics of the sacrum
- may be partially or completely fused with it
- seen as 4 lumbar vertebrae
- superior aspect of the sacrum assumes characteristics of the 5th lumbar vertebrae
- seen as 6 lumbar vertebrae
The angle of the upper surface of the sacrum with the horizontal increases during
- anterior tilt
What does anterior tilt and lordosis do to the spine?
- increases vertical shear force between vertebrae
- elongates and weakens ligaments and discs
T12-L1 apophyseal joint
L5-S1 apophyseal joint
- shear stress can lead to segmental instability
- translation of the vertebral body
spondylolysis is a disruption of
disruption of the pars interarticularis without anterior advancement of the vertebral body
spondylolisthesis is a disruption of
pars interarticularis with anterior advancement of the vertebral body
- weakness can lead to a forward slide of a superior lumbar vertebra over the adjacent one
- can also result from a congenital vertebral deficit that presents when excessive exercise is done, e.g., gymnasts
What's in the vertebral canal?
- spinal cord
- nerve roots
The dural sac containing the spinal cord, nerve roots, and meninges is called _________
Where do segmental nerves exit?
all but cervical exit below the vertebra of the same number
The spinal cord exits at level _______ at the ________
- conus medullaris
What is below the conus medullaris?
What does the cauda equina consist of?
lumbar and sacral dorsal and ventral roots
In the cervical spine herniation of the C4-5 disc impinges on the
Why do you get a L5 nerve compression with L4-5 herniation?
because of the height of the disc
In the lumbar spine, where do the nerves emerge?
- superior to the discs
- below the vertebrae of the same number
Why do the nerves descend from the spinal segment of origin to the vertebral level of exit?
because of the relative shortness of the spinal cord
herniation of L4-L5 vertebra
- herniation occurs inferior to L4 nerve, sparing it (because foramina are large and superior to body)
- get compression of the L5 nerve instead
intrinsic back muscles supplied by primary dorsal rami
order of erector spinae medial to lateral
important muscles deep to erector spinae
- quadratus lumborum
anterior pelvic tilt occurs when _______________ through action of which muscles?
- the spine is extended
- lumbar extensors and hip flexors
posterior pelvic tilt occurs when ____________ through action of which muscles?
- the spine is flexed (lordosis eliminated)
- abdominal muscles, hip extensors
- anterior sacral tilt
- posterior iliac tilt
**corresponds with lumbar flexion/posterior pelvic tilt**
- posterior sacral tilt
- anterior iliac tilt
**corresponds with lumbar extension/anterior pelvic tilt**