Complex regional pain syndrome (CRPS) type I: historical perspective and critical issues.

The history of algodystrophy is controversial and its denomination has changed significantly over time. Silas Weir Mitchell described several cases of causalgia due to gunshot wounds that occurred during the American Civil War, increasing knowledge about this clinical condition. A later key milestone in the history of CRPS is tied to the name of Paul Sudeck that, using X-ray examinations, described findings of bone atrophy following a traumatic event or infection of the upper limb. The most widely accepted pathogenic hypothesis, proposed by Rene Leriche, supported a key role of the sympathetic nervous system in the onset of the typical clinical picture of the disease, which was thus defined as "reflex sympathetic dystrophy". In the 50s John J. Bonica proposed a staging of CRPS. In a consensus conference held in Budapest in 2003, it was proposed a new classification system that included the presence of at least two clinical signs included in the four categories and at least three symptoms in its four categories. There have been other classification systems proposed for the diagnosis of CRPS, such as Veldman diagnostic criteria based on the presence of at least 4 signs and symptoms of the disease associated with a worsening of the same following the use of the limb and their location in the same area distal to the one that suffered the injury. On the other hand, the Atkins diagnostic criteria are much more objective than those proposed by IASP and are specifically applicable to an orthopaedic context. However, current classification systems and related criteria proposed to make a diagnosis of CRPS, do not include instrumental evaluations and imaging, but rely solely on clinical findings. This approach does not allow an optimal disease staging especially in orthopaedics.