Back To Basics - Discs
Most of us have heard the phrase ‘slipped disc’, often during a conversation about back pain. But few of us know much about our discs and what is meant when people complain about them slipping! This is our back to basics guide – disc edition!
What is a disc?
Your spine is an amazing structure running all the way from your skull down to your pelvis. It is made up of 24 freely moving bones (called vertebrae) and discs which sit between them.
The discs are round and flat, and have a structure somewhat like a jam doughnut. No they aren’t edible, and no they won’t put you back 12 syns! But like a jam doughnut the disc is made up of a tough outer layer (the annulus fibrosus) and a soft gel-like inner layer (the nucleus pulposus). These two components of the disc allow it to absorb the shock and stress that the spine is put under while retaining its structure.
Interestingly, 80% of the disc is made up of water, but the disc itself has a poor blood supply and because of this natural recovery can be slow.
What do the discs do?
The discs are unique. They primarily work as shock absorbers, much like the suspension on your car or bike. By absorbing the forces the spine is subjected to, the discs protect the vertebrae and the spinal cord. They also work alongside ligaments to hold the spine in place and allow us the flexibility we require during bending, twisting and stretching movements.
What can go wrong?
The truth is a disc cannot ‘slip’ as they are tethered into position. However, just like the suspension in your car, they can become overworked and suffer painful consequences:
1. Discal irritation / annular tear – whereby the fibres of the tough outer part of the disc can ‘fray’ and tear. The inner gel-like substance remains where it should, but inflammation around the disc can cause a great deal of discomfort.
2. Disc bulge – the tough outer layer of the disc weakens allowing it to ‘bulge’ as depicted in the image at the bottom of the page. In some circumstances the bulging disc can compress nearby nerves causing excruciating shooting pain into the legs, more commonly known as sciatica.
3. Disc herniation- this is the most severe of the disc injuries which occurs when the outer fibrous layer can no longer contain the inner gel-like substance which then ‘herniates’ out of the disc.
4. Wear and Tear - Although not necessarily an injury, the discs (like the joints of the body) suffer from use over time. As we age the discs of the spine naturally narrow and dehydrate. This doesn’t always cause pain but increases the risk of injury.
How can chiropractic help?
If the wheel alignment of you car is off, even fractionally, what happens? The tires wear unequally over time and this increases the risk of a blowout. Similarly with the spine, if the vertebral alignment isn’t correct the discs wear unequally, they weaken and are at higher risk of an injury.
Chiropractic care realigns the bones of the spine so that pressure is evenly distributed over the entirety of the disc, both significantly speeding up the recovery process and reducing the chances of further injury.
If you are currently unfortunate enough to be suffering with a disc injury, care is aimed at removing the pressure off the disc and the surrounding muscles, allowing your body to heal itself in the most efficient way.
For advice on preventing disc injuries please see our blog '5 Top Tips for Preventing Lower Back Pain'