Truths, errors, and lies around “reflex sympathetic dystrophy” and “complex regional pain syndrome”

Abstract

The shifting paradigm of reflex sympathetic dystrophy–sympathetically maintained pains–complex regional pain syndrome is characterized by vestigial truths and understandable errors, but also unjustifiable lies. It is true that patients with organically based neuropathic pain harbor unquestionable and physiologically demonstrable evidence of nerve fiber dysfunction leading to a predictable clinical profile with stereotyped temporal evolution. In turn, patients with psychogenic pseudoneuropathy, sustained by conversion-somatization-malingering, not only lack physiological evidence of structural nerve fiber disease but display a characteristically atypical, half-subjective, psychophysical sensory-motor profile. The objective vasomotor signs may have any variety of neurogenic, vasogenic, and psychogenic origins. Neurological differential diagnosis of “neuropathic pain” versus pseudoneuropathy is straight forward provided that stringent requirements of neurological semeiology are not bypassed. Embarrassing conceptual errors explain the assumption that there exists a clinically relevant “sympathetically maintained pain” status. Errors include historical misinterpretation of vasomotor signs in symptomatic body parts, and misconstruing symptomatic relief after “diagnostic” sympathetic blocks, due to lack of consideration of the placebo effect which explains the outcome. It is a lie that sympatholysis may specifically cure patients with unqualified “reflex sympathetic dystrophy.” This was already stated by the father of sympathectomy, René Leriche, more than half a century ago. As extrapolated from observations in animals with gross experimental nerve injury, adducing hypothetical, untestable, secondary central neuron sensitization to explain psychophysical sensory-motor complaints displayed by patients with blatantly absent nerve fiber injury, is not an error, but a lie. While conceptual errors are not only forgivable, but natural to inexact medical science, lies particularly when entrepreneurially inspired are condemnable and call for peer intervention.