• The annulus fribrosus, whose fibres are arranged in a parallel manner and criss-cross with those of the next layer. Note that it is of mesenchymal origin.
  
  
• The nucleus pulposus, at the center of the disc. It is a fibrogelatinous pulp that is a remnant of the notochord.
  
  
• Hyaline cartilage covering the bone surfaces

Function:

The major functions of the Intervertebral disc include:

1. Acting as a shock absorber.
   
   
2. Transmition of weight.
   
   
3. Holding adjacent vertabrae together.

Note:
As a result of aging, the nucleus pulposus becomes increasingly fiibrocartilagenous and contains less water, while in people relieved of gravity (astronauts) there is an increase in height of several centimeters.

In what direc

tion does the IVD herniate in injury and what is the effect of this?

Function

• To hold vertebrae together