One of the most common causes of back pain is a slipped or prolapsed disc and it really isn't difficult to understand why this causes so much trouble. It is the bones of the spine which give the back its strength. But if the spine only consisted of bone then you wouldn't he able to bend to tie up your shoe laces or pick things up off the floor. So between the bones there are 23 intervertebral discs which act as bendy shock absorbers.

The outer part of each disc is tough and rather rubbery but inside that there is a soft, squashy area called the nucleus pulposus (85 per cent of each disc is made up of water). It is this central soft part of the disc that gives us the ability to touch our toes.

When you are lying in bed at night the disc expands and sucks in water and food. But when you are walking or carrying something heavy the bones compress the discs and squeeze out much of the fluid.

During the average sort of day most of us lose about a centimetre in height because our discs are compressed. You gain that lost height again every night.

If your spine consisted only of bone it would be very stiff and immobile. But unless there is something wrong with it your spine is remarkably bendy. There are two things which make this possible.

First, there is the shape of the bones. Your first cervical vertebra (which is also called the 'atlas' bone).
It allows your head to nod backwards and forwards, and to tilt sideways. Your second cervical vertebra (also known as the 'axis' bone) allows your head to turn to the left and to the right. The other bones of the spine also allow a certain amount of backward, forward and sideways movement.

More important even than the shape of your bones are the intervertebral discs' the 23 narrow spongy shock absorbers which fit between the 24 separate bones of your spine. Without the discs these bones would grate and crunch evey time you moved. The disc has a strong fibrous outer casing called the antiti-fibtostis and a soft, squashy, jelly-like interior called the nucleus pulposus which is reinforced with strands of fibre.

Intervertebral discs have very little in the way of nerve supply and contain no blood. They are made up largely of water As you get older the amount of fluid in your discs will diminish slightly and as a result you will get shorter.

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Backache
Back Pain
Lower Back Pain

Slipped disc, bulging or herniated disc, back pain