[Nerve block therapy for intractable pain: 3 cases of erythlomelalgia].

Erythromelalgia is a rare condition that is characterized by the triad of redness, increased temperature, and intense pain of feet or hands. This syndrome was first described in 1878, however, universal classification, precise mechanism and successful medical treatment of erythoromelalgia have not been described. We experienced 3 cases of erythomelalgia in our outpatient pain clinic that showed the different progress. One patient experienced the long-term pain complicated with neuropathic pain. The pain of other two patients was eliminated early by nerve block treatments, and they did not showed chronic pain. From the prophylactic viewpoint of chronic pain, the most considerable matter is early and certain elimination of severe pain under certain diagnosis. In this article, the mechanisms of passing into the chronic pain state as well as the efficacy of neural blockade for intractable pain such as erythromelalgia are discussed.