"Minor" causalgia, perhaps not as good a term as posttraumatic sympathetic dystrophy, has been well described in an article in this issue by Wirth and Rutherford. It differs in many respects from major causalgia described by Weir Mitchell. His soldiers from the Union Army developed intolerable pain in an extremity after a penetrating wound causing partial interruption of a major nerve. This was characterized by intense burning pain in the area supplied by the injured nerve. The pain, evoked by the lightest touch, has the peculiar characteristic of becoming agonizingly severe with emotional stimuli and exposure to cold (or tropical heat, as observed by Denny-Brown in Burma). Trophic changes develop with glossy skin and atrophy from disuse.
The so-called minor causalgia results from nonpenetrating and often relatively mild trauma to an extremity, most often the wrist, hand, or ankle. The pain is not necessarily burning in quality and is more