What is an intervertebral disc?

What is an intervertebral disc?

A lot of our time is spent at the clinic talking about discs and different states they can be in, but what is a disc?

A disc is a fibro-cartilaginous structure that are situated between the vertebrae, the bones of the spine. They are located from the bottom of the skull right the way down to the tail bone. The purpose of the discs are to provide a shock absorbing system and to allow the spine to move.

The discs themselves have two parts to them; the outer part is called the annulus fibrous and the central part is the nucleus pulposus. Think of a jam do nut, the outer edge is the dough (the annulus), and the central part is the jam, (the nucleus).
 

Both parts of the disc contains water but more so the nucleus. This water content varies through the day. That is why you are slightly taller in the morning! The discs ability to hold water decreases with age as the discs become dehydrated. Amongst other things this contributes to the loss of height with age.

The disc is just part of a complicated system of the spine that allows us to do our daily activities.

We will discuss other parts of the spine and what happens when things go wrong in future blogs!