Clinical update on other pain syndromes.

Abstract

Objective: To review clinical features, pathophysiology, and management of localized and regional pain syndromes. Finding(s): Localized pain syndromes often follow tissue damage and are characterized by persisting pain, secondary hyperalgesia, and allodynia. Evidence for ongoing peripheral nociception is lacking, with central [dorsal horn and beyond] sensitization allowing explanation of clinical features. Regional pain syndromes have similar characteristics but involve larger areas of pain, hyperalgesia, and allodynia, usually including the spine. The role of spine-related reflex mechanisms, particularly mechanoreceptor input, seems important. Central sensitization of the dorsal horn pain transmission neurones in localized pain syndromes seems dominated by peripheral nociceptive input, but in regional pain syndromes supraspinal influences appear to play the more important role. Management of both variants needs to be multi- and inter-disciplinary for best results. Conclusion(s): Pain syndromes limited only to regions of the musculoskeletal system are important and common. Further understanding of the interaction between peripheral and central components of the pain system, particularly the influence and response of the spine-related mechanoreceptors in this setting, may allow for the development of uniform nomenclature, paradigms, and treatment-evaluations in patients with musculoskeletal pain.