Mondo Description Complex regional pain syndrome (CRPS) is a rare neurologic disease painful progressive condition that corresponds to a group of disorders characterized by a disproportionate spontaneous or stimulus-induced pain, accompanied by a variably mixed myriad of autonomic and motor disorders including symptoms such as swelling, allodynia, skin blood supply and trophic disturbances. CRPS most often affects one of the arms, legs, hands, or feet and usually occurs after an injury or trauma to that limb.