Pain mechanisms in neuropathy.

Current opinion on "neuropathic" pain is chaotic and divided. This review is a summary attempt at describing the principal hypotheses that are currently entertained and at interpreting the basic underlying mechanisms of these pains. Rather than relying preferentially on rigorous data generated from neurophysiological animal experimentation, reasonable priority is given to evidence derived from rigorous neurophysiological and psychophysical studies in human volunteers and patients. Issues such as the concept of "centralization" of neuropathic pain mechanisms, which dwell excessively upon extrapolation from animal experiment to human clinical reality, are highlighted as questionable. Psychogenic pseudoneuropathy, an entity of high clinical prevalence and low appreciation by basic scientists and the reflex sympathetic dystrophy establishment, is also given the emphasis it deserves.