Reflex sympathetic dystrophy (RSD) is an incompletely understood response of the body to an external stimulus, resulting in pain that usually is nonanatomic and disproportionate to the inciting event or expected healing response. As early as the 1930s and 1940s, a short circuit in the reflex arc between somatic afferent sensory fibers and autonomic sympathetic efferents was postulated to explain overall increased sympathetic stimulation. Currently, no specific pathologic, histologic, or biochemical markers of this condition exist.
Although controversy continues regarding the term, definition, and process of diagnosis, the presence of sympathetically maintained pain is accepted as an etiology for, or at least as a significant component of, many regional pain problems.
Synonyms and related keywords:
complex regional pain syndrome type I, CRPS-I, sympathetically mediated pain syndrome, SMPS, causalgia, algodystrophy, algodynia, Sudek's atrophy, Sudek atrophy, shoulder-hand syndrome, RSD
Lawrence E Holder, MD 2005