What is a spinal disc?The disc is atough, gristly shockabsorber that sits inbetween the bonesof the spine.It separates thebones, lets themmove and supportsthem.
What does a Normal Disc looklike?A normal disc has twodifferent parts A tough outer areacalled the annulusfibrosisA slightly softer innerarea called thenucleus pulposis
A Normal Disc from the TopIf you look at a discfrom the top downit looks a little bitlike a tree stump.Rings of toughouter fibres encirclethe softer innercentre.
How Does the Disc WorkWhen weight goesthrough the discthe pressureinside increases -this improves thediscs strengthand stiffness.The pressureinside spreads theload evenlyacross all thesurfaces.
What is a Disc Bulge?A disc bulge occurswhen the tough, outerlayer becomes slightlyweaker. This allows thecentre to shift away fromthe middle.This shift causes theouter area to bulge -usually backward andsideways.
Disc Bulge from the SideWhen a disc bulges itsometimes squashesor irritates a nerve root.The most commonlyirritated nerve roots arethe ones that make upthe sciatic nerve.This is why disc bulgesare one of the mostcommon causes ofsciatica.Sciatica = irritation ofthe sciatic nerve.
What is a Disc Herniation orProlapse?A prolapse orherniation is moresevere than a bulge. It is caused by theouter area weakeningenough to allow theinner, softer annulus toescape out of the disc.A prolapse can alsoirritate or squash anerve.
What is a Slipped Disc?A slipped disc is amyth.Discs can’t slip asthey are firmlyattached to thebones above andbelow.When people talkabout a slipped discthey are talkingabout either a bulgeor a prolapse.