Advent of Biomarkers and Their Role in CRPS Diagnosis and Management

As a new science, biomarkers have been defined by a Definitions Working Group (Clin Pharmocol Ther 2001;69:89–95) in the following language, “any measurement reflecting an interaction between a biological system and a potential hazard, which may be chemical, physical or biological, the measured response may be functional and physiological, biochemical at the cellular level or a molecular interaction.” In other words, a biomarker can be a surrogate for a phenotypical expression reflected in its measurement, which could be a biochemical or a physiological measurement at a cellular or molecular level. As such, biomarkers can aid in the diagnosis, the results of a therapeutic intervention, or its prognosis and the temporal monitoring of a disease. CRPS, because of its multiple pathophysiologies, all of which are only incompletely understood, lends itself to the use of biomarkers, many of which are already described in the literature. The challenge for the future will be to identify those specific biomarker(s) that can be sourced by practising clinicians and not just in academic medical centres. The following account addresses such questions.