Lumbar Disc

Question 1

Lumbar Disc Function

Answer 1

1. Shock absorber
2. Distribute load applied to the spine
3. Allow for movement between the vertebra
4. Degeneration occurs over the lifespan

Question 2

Lumbar Disc Anatomy

Answer 2

Annulus Fibrosis : Fibrocartilage, Sharpey’s fibers in outer ring
Nucleus Pulposus: Hydrophilic mucoid tissue, water-binding capacity decreases with age, eventually replaced with collagen

Question 3

Lumbar Disc: Endplate

Answer 3

Allows fluid to move between disc and vertebral body
Disc receives nutrition by diffusion through the endplate.
Pressure in the disc lowers with normal lordotic curve.
Pressure can push fluid into vertebral body if defects are present

Question 4

Lumbar Disc: Loading

Answer 4

Different posture increase loading on the disc.
‘Lifting wrong’ has the greatest pressure on L3 disc