Although most medical experts believe RSD is characterized by an overactive sympathetic nervous system response, there is much debate about the physiology of the disease. The name reflex sympathetic dystrophy was given to the disease in the 1940’s but has undergone recent scrutiny.
Many in the medical field believe that the name “reflex sympathetic dystrophy” is somewhat misleading considering only a portion of the patients respond to sympathetic blocks, indicating that not all of the pain in this syndrome is related to the sympathetic nervous system.
In response to this frequent inconsistency, the International Association for the Study of Pain has adopted the term Complex Regional Pain Syndrome (CRPS) to describe the debilitating pain syndrome that was commonly known as RSD.
RSD / CRPS typically occurs following trauma or surgery to an extremity. Often the injury is relatively minor and the pain is greatly disproportionate to the injury. Although the severe pain may immediately follow the injury, it often does not and instead follows the injury days or even months. The pain is often characterized as an intense burning type pain.