Dr. DiDuro states that there are two broad categories of pain. One is produced by the activity of nerves in response to skin, bone, connective tissue, muscles, and visceral injuries. This is called nociceptive pain. 'Nociceptive' means that the pain is carried from pain receptors at the ends of nerves in various tissues to the brain, giving alarm to damage. The other type of pain he discusses is the pain produced by damage to or dysfunction of nerves, themselves, either in the central (brain and spinal chord) nerve system or in the peripheral (all the nerves outside the brain and spinal chord) nerve system.
The first pain type, nociceptive pain, is the easiest to treat because it is usually the result of an injury that will heal over time and with a little help. Disc injuries, ligament sprains, and muscle strains fall into this category. When the injury is mended, the pain goes away.
The second type of pain, neuropathic pain, is more problematic. Nerve tissue takes a long time to heal, and, in some cases, it never does. The healing process can simply be so slow that the nerve dies or becomes permanently damaged before the healing process can be completed. Injured nerves have nerves in them and on them that will continue to signal the damage to the brain in the form of pain. If the nerve damage is permanent, the signal can become permanent, too. Nerves that are injured so badly that they cease altogether to function, if they are sensory nerves, stimulate a compensation for the lack of normal sensory input to the brain that substitutes pain signals for the normal sensory signals. These are transmitted through other nerves.
Many patients that present in chiropractic offices have only the first type of pain, nociceptive pain, and these are the cases that are most successfully treated. Some patients, however, have a combination of the first and neuropathic pain, the second type. It either takes longer to get these patients well, or their pain is only reduced to a certain point - very often a degree of pain that they call their 'normal pain.' Some patients, sadly, suffer mainly from neuropathic pain and their treatment is either very protracted or beyond the capabilities of conservative intervention.
Interestingly enough, strident exercise has been observed to be beneficial in neuropathic pain syndromes. It is my clinical belief that the pounding effect of jogging, of all things, is beneficial to both nociceptive pain and neuropathic pain originating from the lumbar intervertebral discs. Because the exercise, itself, is often painful in these cases, any exercise regimen undertaken should be coupled with other treatment measures like chiropractic adjustments, massage therapy, and acupuncture. Too, it must be understood that patients are rarely 'cured' forever of disc pain of either type, and that regular exercise and some form of supportive care must become a way of life if the achieved improvement is to be maintained.