A taxonomy of chronic pain syndromes

This article has had as its purpose the delineation of the complexity of the production of pain on an organic basis as opposed to any psychological amplification. The issues addressed apply directly to the problem of spinal pain. Classical nociception arising in the structures of the spine thus would include the application of mechanical and chemical stimuli to muscles, ligaments, apophyseal joint capsules, bone, and other structures with adequate innervation, particularly the anterior dura and its extensions. Disease and injury productive of direct nociception are well understood sources of spinal pain. Less well understood, but of at least equal importance in the spinal pain problem, are the activities within the central nervous system that control the transfer of nociceptive information to the higher centers. These activities account for some of the variability known to occur in the experience of pain. Further, the fact that the nervous system changes its activities in response to chronic pain, particularly that arising from damaged neural elements, is of paramount importance in understanding how chronic pain syndromes differ so greatly from simple nociceptive events. Insidious deafferentation ongoing in spinal nerve roots subject to chronic compression and fibrosis offers a fertile field for research into the origin of permanent pain in patients in whom application of accepted therapies does not result in relief. All of this material must be considered by the clinician who is challenged with analyzing spinal pain problems in patients.