What this means is that part of the disc is either degenerated, bulged out, or both. You see, when a disc degenerates, (in other words arthritis) the disc flattens and breaks down. This can be much like a flat tire; it flattens and bulges out. Since that material bulges out then there is less of it between the vertebrae in the neck.
This decreased disc space will then compromise the space the nerves in the neck have when they exit off of the spinal cord to travel to various parts of the body such as your arms or upper back.
Some degeneration is normal as we age. The discs will dehydrate and flatten a bit, but if your getting arm pain, neck pain, or tingling in the hands, then chances are youve got a little more breakdown than you should.
Injuries to the neck and shoulder, poor posture, and spinal misalignments will cause the degeneration or arthritis to happen faster, perhaps leading to this neck and arm discomfort.
An injury to the neck can also cause a fairly healthy disc to bulge or even herniated. This will also show as a decreased space on an x-ray. The radiograph will show the bone, not the soft tissue like the disc, but you can see the space. If there is decreased disc space compared to other levels you can bet something is going on.
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