The term causalgia (Greek: kausis – burning, algos – pain) was introduced by Silas Weir Mitchell in 1864. It was used to describe a rare syndrome that followed a minority of partial peripheral nerve injury in the American civil war. Triad: burning pain, autonomic dysfunction and trophic changes.
CRPS Type II (AKA major causalgia) follows nerve injury (originally described after high velocity missile injuries). CRPS Type I (AKA reflex sympathetic dystrophy or causalgia minor) denoted less severe forms, and has been described after non-penetrating trauma 1).
Shoulder-hand syndrome and Sudeck's atrophy are other variant designations. In 1916, the autonomic nervous system was implicated by René Leriche, and the term reflex sympathetic dystrophy (RSD) later came into use 2) (but RSD may be distinct from causalgia) 3).