Without proper care, subluxation can cause permanent nerve damage, but...
What is a Subluxation?
Subluxation is defined as a joint that is out of proper position or not able to go through full range of motion. This can happen in any joint of the body. Chiropractors primarily work with subluxations of the spine. These are called vertebral subluxations.
If a subluxation is left undetected and neglected, the restriction of motion or poor position will lead to scar tissue deposits which further restrict the motion. This will eventually lead to arthritis. Over time, this process will continue to deteriorate until little to no motion is possible in the joint. Even in the advanced stages this process may not cause pain.
Chiropractic adjustment attempts to reduce or remove subluxation.
One of the challenges is that this process happens for most people without them even knowing it. Just because you have subluxation does not mean that you will have pain. This is one reason why most chiropractors recommend getting checked for subluxation regularly, just like most dentists recommend regular dental check-ups.
The bigger challenge with neglected subluxation is nerve damage that can become permanent. Movement in any joint of the body will stimulate a nerve response called proprioception. Lack of movement will stimulate a different stimulus called nociception. Proprioception is positive and nociception is negative. There is a great video called Spinal Hygiene that discusses the relationship of movement in your spine and how it affects the cerebellum of your brain. The bottom line is that movement is necessary for your brain to work properly. Lack of movement, creating nociception, will interfere with proper cerebellar function. When it becomes more advanced, a stimulus is sent to the cortex of your brain, which is responsible for conscious thought. When that happens you will feel the emotion of pain. This is why you may not feel pain even when subluxation is present.
Nociceptors can fire and you will have decreased function of some of the vital organs and processes of your body but may still not feel pain. When you feel pain, the problem has usually been present for a long time.
This is why many Chiropractors use the autonomic nerve chart to demonstrate to folks that if a subluxation is present at a certain level it could result in malfunction of the organs at the end of the nerves. For example, a subluxation at C6, the 6th vertebrae below the head, can result in thyroid problems.
While this is true, a more accurate explanation of the devastating effects of subluxation is understood by the concepts that science has revealed regarding proprioception and nociception as described above and on the spinal hygiene video.
One important point to consider is that having subluxation present, complete health of the body cannot be present. Chiropractic adjustments is centered around reducing or removing subluxation so that proper nerve function can exist which translates into better health, sometimes even allowing conditions or symptoms a person is feeling to disappear.