[Complex regional pain syndrome. Current status]

Complex regional pain syndrome (CRPS) is a disorder or group of disorders that develop as a consequence of previous trauma with or without evident nerve injury. The syndrome is characterized by presence of spontaneous pain, hyperalgesia and allodynia, sensitive changes, blood flow changes, sweating, and trophic changes. The disease is characterized by symptoms of acute inflammatory states as well as by chronic neuropathic changes. Pain is associated with changes generated by the autonomic nervous system. Spinal neurons can increase their sensitivity to these autonomic changes. At a supraspinal level, reorganization of somatosensorial cortex is seen. Creation of diagnostic criteria has been difficult due to the plentiful symptoms of CRSP. Sympathetic blockade with phentolamine is the most commonly approved examination to diagnose sympathetic maintained pain. Several strategies have been used for treatment of CRPS, but with none of these has sufficient evidence of treatment effectiveness been afforded.