Phys of IVD

Question 1

How long does it take for nutrients diffuse into the IVD of a normal disc and one with DDD

Answer 1

normal- 6 hrs
DDD- 12-18hrs

(increased calcidication of endplates)

Question 2

What do you see a loss of in DDD

Answer 2

loss of preteoglucans ability to bind water

Question 3

What are the molecular mechanisms inherent to DDD

Answer 3

• Cells shift from notochordal cells to more chondrocyte like cells
• Lots of collagen II and I (I not usually in disc)

Question 4

what is the mechanism that causes lower viscoelasticity in DDD

Answer 4

Core protein changes in DDD so aggrecans are cleaved meaning that less water can be bound

Question 5

What are the 4 major steps to DDD

Answer 5

1. Injury, genetics or cumulative effects from lifestyle
2. Increase in release of pro inflammatory molecules (inflamation)
3. Degradation of ECM of disc
4. Apoptosis, leading to breakdown of DNA, cellular pros

Question 6

What pro inflammatory molecules have been found to be more common than those with sciatica

Answer 6

IL6, IL8, PGE2