Complex regional pain syndrome (type I, RSD; type II, causalgia): controversies.

Introduction of the term complex regional pain syndromes (CRPS) as a replacement of the older terminology, reflex sympathetic dystrophy (RSD) and causalgia, has achieved two goals: it has focused attention on the diagnosis and treatment, and sent basic scientists back to their laboratories. The relation of sympathetically maintained pain and sympatholysis is examined, particularly as a neuropathic process that is found in many conditions, including CRPS. This review also focuses on recent observations proposing a pathologic basis in support of diagnosis and treatment of these disorders.