Diagnosis of complex regional pain syndrome: signs, symptoms, and new empirically derived diagnostic criteria.

This review will discuss the relevant history of the taxonomy and eventual development of diagnostic criteria of what is currently called complex regional pain syndrome. The authors will take their discussion through the early days (at which time the disorder was called reflex sympathetic dystrophy) through consensus-developing conferences to the current conceptualization of the criteria as published by the International Association for the Study of Pain's Task Force on Taxonomy in 1994. The authors will also mention the recent work of the closed workshop held in Budapest in 2004, where clinical and research criteria were proposed; these criteria were published in 2005. The review will also address issues of staging and subtyping the syndrome, as well as a discussion of the salient signs, symptoms, and tests appropriate for use in the diagnosis.