A disc issue can be classied in many ways. First let's talk about the kind of disc it may be overall:
- There's Disc Bulges
- A Degenerative Disc
- Herniated Disc
- A Disc Tear or Fissure
Let's talk about each one. But first to do that you need to know that the discs is human beings are between almost each bone of the spine and are like a cushion or shock absorber. The is a soft interior called the nucleus and an outer, more cartilagenous exterior, called the annulus.
A Bulge is when the inner disc pushes outward which inturn pushes on the annulus (creating a "bulge"), but dis material does not break through outside the disc.
A Disc can also flatten, much like a pankake or flat tire. This is typically seen as degeneration. It will often flatten and bulge. Now that bulge may be concentric (all the way around), or bulge more at the points of weakness. On an image one may see other forms of degeneration or arthritis such as bone deterioration or something of the like.
Next let's talk about a hernation. When that disc material does come out, or breaks through the annulus, you have a disc herniation. That herniation can technically be a protrusion or extrusion.
In other words is the base of the herniation bigger or smaller than the distance from the disc outwards.
Next, where is the disc: central, lateral, or poterolateral; these are the most common. So, is that disc straight back, is it on the left or right side, or is it posterolateral (back and side), weakest area of the disc. This type of disc often nears or contact the nerve root because this is where the nerves exit off the spinal cord.
There can also be a disc sequester. This is when that hernation breaks from the body of the disc. Sequestered discs can also be a problem because they are free floating. This means they can move to an unfavorable spot...
Adisc can also have a tear or fissure. This is where the disc may protrude out of. If the tear isn't very bad however, and the disc material retracts back however, the fibers of the disc may heal to a certain extent.
Lastly, I thought of note is that you may seem the term "disc" or "disk" which refer to the same thing. Keep in mind that many use some terms fairly synonomously, such as in the previous example or the words: arthritis and degeneration, etc.
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