Spinal Discs 101
- Posted on: Jul 30 2018
When you hear people talking about their back problems, they’ll say things such as “I slipped a disc.” or “I have a disintegrated disc.” But what are the spinal discs? And what happens to them that make for such painful symptoms?
Since we deal with the spinal discs every day at DFW Center for Spinal Disorders, here’s a primer on the jelly donuts of your spine.
What are Rhe Vertebral Discs?
There are a total of 23 spinal discs in the spinal column. They have a three-function role that is unique to any other structure in the body. The discs:
- Act as shock absorbers in the spine, keeping the vertebrae from coming into contact with each other.
- Act as tough ligaments that hold the vertebrae together to make the spine.
- Are cartilaginous joints that allow for slight mobility in the spine.
The discs are made up of two parts. There is a tough outer portion and a soft inner gel. You can think of the discs as like a jelly donut.
The outer portion is called the annulus fibrosus. This is a touch circular exterior composed of concentric sheets of collagen fibers that house the inner core.
The inner core of the disc is called the nucleus pulposus. This is a loose network of fibers suspended in a mucoprotein gel.
The two parts of the disc are kind of like two circular pieces that fit within each other. The annulus fibrosus has cartilaginous endplates that firmly attach the disc to the vertebrae above and below the disc.
Gel Becomes Gummy Bear Becomes Old Taffy
When we are born, our discs are made up of around 80% water. This makes the disc very pliable and allows loads to be easily spread across the discs. But as we age, the discs dehydrate and become stiffer. Now they are less able to spread the force applied to the spine across the discs. This happens to everyone, but for some people it can begin to create problems with pain.
In some cases, as the discs degenerate, they can begin to allow some instability that can create leakage of proteins from the inner core of the disc. These proteins can inflame the nerve fibers in the area. Otherwise, improper lifting or twisting can cause the disc to rupture, allowing the inner gel to push outward. This will often press on a nerve root exiting the spinal column causing chronic pain.