Complex Regional Pain Syndrome: Time to Study the Supraspinal Role?

The International Association for the Study of Pain (IASP) defines complex regional pain syndrome (CRPS) as a spontaneous or stimulus-induced pain that is disproportionate to the inciting event and is accompanied by a wide variety of autonomic and motor disturbances, in highly variable combinations. As noted in the definition, there are a number of possible causes for CRPS. These include tissue damage, nerve damage, casting, traumas, fractures, burns, frostbites, strokes, and other non-identifiable causes. The symptoms of reflex sympathetic dystrophy that do not accompany nerve damage are generally classified as CRPS type 1, while those accompanying nerve damage - such as causalgia - are classified as CRPS type 2. Although various reports have suggested different incidence rates, the condition has generally been found in 20-30 cases per 100,000 persons; the incidence rate of CRPS type 2 is reported to be 0.82 cases per 100,000 persons.