Degenerative Disc Disease

Question 1

Definition DDD

Answer 1

Degeneration of the annular fibers of the intervertebral Disc

Question 2

Disc’s between vertebrae functions

Answer 2

●Disc’s are shock absorbers
●They allow for movement between the vertebrae
●Flexible but strong

Question 3

2 components to disc’s

Answer 3

●Annulus fibrosus (annular fibers)- posterior is thinner + less firmly attached
●Nucleus pulposus- jelly in center of Disc (annular fibers surround it)
-has high H2O content 88% at birth, decreasing at 65/70% into old age
-Disc can change size, when
Compressed the H2O in the nucleus is forced out, will return to disc at night
-more movement in cervical and lumbar spine due to ribs- cervical spine more rotation than lumbar

Question 4

Facet jt

Answer 4

Direct + controll the degree of vert mvmt in all mvmts (flex, ext, side bending, rotation)

Question 5

Meniscoids

Answer 5

Shock absorbers between facet jts

Question 6

Optimal seat position

Answer 6

10° in forward incline

Question 7

Degeneration of Disc

Answer 7

●Happens to everybody
●Starts as early as 20 yrs old
●Lumbar + cervical most affected
●The post annulus fibers are thinner + shorter

Question 8

What portion of the Disc fibers weaken first?

Answer 8

Posterolateral portion of the Disc weaken first

Question 9

Herniation

Answer 9

Men affected 3:2
Usually happens at L4, L5, S1 (acount for 98% of low back injuries)
Usually due to flexing + twisting at the same time

Question 10

Stages of herniation

Answer 10

●Protrusion- (usually posterolaterally) Disc bulges annular fibers intact- herniation may follow if fibers tear
●Prolapse- outer most annular fibers hold nucleus
●Extrusion- annular fibers pierced (nucleus enters epidural space)
●Sequestration- fragments of nucleus/annular fiber found outside of Disc

Question 11

Other terms used with D.D.D

Answer 11

●Spondylosis- Degenerative change in facet jts
●Slipped Disc- herniation
●lumbago- low back px
●Sciatica

Question 12

Cause of D.D.D

Answer 12

Chronic overloading of Disc leading to annular fiber microtearing + migration of nucleus

Question 13

Symptom picture: 3 stages

Answer 13

●Dysfunction- Biomechanical changes result in weakness, bulging + minor tears in annulus
- painful facet jt irritation, jt fusion, mm spasm in cervical spine, meniscoids become trapped between jt surfaces
●Instability- post annular fibers/jt capsules become lax, verts become hypermobile- leads to stress on ligs + jt capsul
- nerve entrapment can occur
●Stabilization- loss of disc material/height, intervertebral foramen narrows, jt capsules + post ligs fibrose. Degeneration may spread