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Flashcards in IVD Deck (27)
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1

there are ___ IVD given a numeric name based on the segment ABOVE, and they fxn in weight bearing and motion

23

2

IVD constitute __-__% of vert column height

20-33

3

-greatest IVD:VB height ratio is in the ___, least in the ___, and middle is the ___
-greater ratio indicates greater spinal segmental mobility

cervical
thoracic
lumbar

4

___ __ of the IVD has 70-90% water content, which decreases with age

nucleus pulposis

5

___ nuclei fill 30-50% of disc area in cross section, and they are more posterior than central, while ___ discs are less defined & the annulus is minimal on the lateral borders and only a thin strip in back

lumbar
cervical

6

concentric laminated bands with same direction W/I a band but opposite directions in any two ADJACENT bands

annulus fibrosis

7

annulus fibrosus bands seem to cross e/o obliquely, ea forming an angle of ___ to the VB

30 degrees

8

annular fibers are firmly att'd to the ___ __ in the inner zone, while periph zone fibers attach to the VB via __ __

cartilaginous endplates
sharpey's fibers

9

the __ & __ reinforce the annular fibers, and the latter narrows from C-L

ALL
PLL

10

the weakest area of the annulus is the ___ aspect, making it the MOST LIKELY spot for __ __ in the lumbar spine

posterolateral
disc herniation

11

-the ___ portion of the cartilaginous end plate (CEP) is fairly impermeable while diffusion of nutrients occurs in the __ portion
-end plate supplies nucleus pulp w/ most of nutrition

outer
central

12

no BV go directly to disc:
-annular fibers get blood supply from___
-nucleus pulposus gets supply from ___
-diffusion into disc from endplate

adjacent soft tissues
vertebral bodies

13

IVD undergoes rapid degen and has limited self repair bc it is __ & __, but has increased vasc & innervated by sensory nerve fibers during disc degen (increased pain)

avascular
aneural

14

overnight, the disc ___ which increases resistance to forces, but during the day fluid exits the disc, disc space ___ and there is a loss in seated height of ~20mm
-INCREASED ROM lumbar flex

expands
narrows

15

the IVD is ___ and there is variation in loading in different parts of the disc

viscoelastic

16

___ of nucleus pulposus results in ___ of annular fibers

compression
tension

17

flexion results in __ of anterior disc and __ in posterior disc

compression
tension

18

with age & biomech stresses, the disc becomes more ___ and causes decreased __, therefore an injured disc deforms more than a healthy one

fibrous
flexibilty

19

___ varies with disc age, level, repetitive load
-decreases with successive loading
-stiffer when loaded rapidly, IVD less effective at shock absorb

hysteresis

20

nucleus RESISTS __ forces and annular fibers have ___ strength, so they contain the nucleus by resisting "stretch"

compressive
tensile

21

the DISC is more susceptible to failure in the area of ___ not compression

tension

22

___ ___ caused from endplate fracture from significant axial load, nucleus migrates into the bodies

schmorl's node

23

-biomech behavior is dep on the state of ___, which is dependent on the __ of the disc
-by age 50, 97% of discs are degen

degeneration
age

24

4 stages/types of disc herniation (see pic in notes slide 41)

1. nuclear herniation (w/i IVD)
2. bulge/prolapse (migrate outside IVD, no rupture)
3. extrusion
4. sequestration

25

disc herniation is assoc with extreme deviated posture including these two motions, as well as with repeated loading

full flexion
lateral bending

26

___ is caused by sudden compressive loading and lateral bending

sudden disc prolapse

27

four common postural habits that increase lumbar spine flexion

crossed legs
squat on heels
lifting light weights
rapid lunging