First, I thought I would maintain that there is a disc between all seven cervical vertebrae with the exception between C1 and C2. This disc material acts as a cushion and is surrounded by and contains nerve connections. For this reason, a disruption to this material can cause pain.
Let’s start with Disc Degeneration- this is age related breakdown of the disc. This is often synonymous with disc desiccation and is accompanied with fibrosis and osteophyte formation of adjacent vertebrae.
Disc Dessication is a disc that has fibrosed or hardened due to loss of water content. You see the disc is made up of an annulus (outer fibers which are slightly harder), then the inner nucleus which is more of a gel-like material. That being said, we can also get neck pain from a tear of the annulus. An annular tear refers to any disruption in the outer disc fibers. Besides a tear you can also have a rupture of the annulus fibrosis.
When someone has a herniated disc they have disc material that has broken out through the annulus. The nucleus pulposis is displaced beyond the margins of the vertebrae.
Next is a Disc Protrusion. It is basically another name for a herniated disc. There are two types; focal disc protrusions or broad based disc protrusions. Focal is when the disc protrusion is less than 25% of the disc circumference. A broad based protrusion is when the disk protrusion encompasses 25-50% of the disc circumference.
When the disc that has herniated out is more wide than it is long (meaning how far it is reaching outward) it is a vs. the next definition. Extruded Disc- this means the disc has come outward further than it is wide. Extruded discs can also be classified as sequestered or migrated discs.
Lastly, a Sequestered disc, also called a migrated disc, is when that extrusion breaks free from its connection to the rest of the disc material and is now a free fragment or “fragmented disc.”
Updated:4/28/2020
Image Source: Columbia Spine
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