What is a Slipped Disc?
Lumbar Disc Herniation or “Slipped Disc”
A “Slipped Disc” is a common term used when someone has a spinal disc injury, however, this term is actually inaccurate as the spinal disc itself cannot slip out of place.
So what does the term actually mean? Let’s understand what a disc is first.
The spine, or vertebral column, is made up of a series of bony blocks, known as the vertebrae. The spine is not a rigid structure as it functions as a combination of joints – it is able to bend, twist and move within its physiological barriers. Between these spinal joints lies the DISC which acts as a shock-absorbing cushion. Each intervertebral disc is a flat, biscuit-shaped structure with a jelly-like centre called the nucleus and an extremely strong outer skin called the annulus.
What is a ‘slipped disc’?
The discs are firmly attached to the vertebrae. They can wear, split or be herniated, but they can’t slip!
This occurs over time as the disc undergoes wear and tear following cumulative strain from repeated bending, twisting, lifting and prolonged sitting, the strong fibres of the annulus can tear, allowing ‘leakage’ of the nucleus out of the centre of the disc.
This is known as a disc herniation.
This ‘leaked’ material may then cause an inflammatory reaction and sometimes put pressure on the spinal nerve that runs next to the disc, resulting in leg pain or Sciatica like symptoms if it affects the discs in the lower back or, arm pain if it affects the discs in the neck. Pain may occur even if the is no herniation, this is when there is internal damage to the disc where it is less likely to get typical signs of sciatica.
Find out what you can do in an Acute Disc Injury Here
Hope that helps you understand a bit more about the condition commonly known as ‘slipped disc’.
By Dr. Cheran Ruben BChiro, BSc(Chiro)
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