Complex Regional Pain Syndrome (CRPS)

Abstract

The term Complex Regional Pain Syndrome (CRPS) is a pain disorder in which the pain is disproportionate to the initial inciting injury. The disorder is complex because it involves multiple organ systems with abnormal blood flow, sweating abnormalities, trophic changes, and fine motor impairment. The pain distribution tends to be regional (not dermatomal), and is not limited to the area initially affected (Rand 2009). The pathophysiology of CRPS is not entirely understood. The pain can be sympathetically-­maintained (responsive to sympathetic interventions) or sympathetic-­independent (Gibbs et al. 2008; Wilson 1999). The diagnosis is excluded by the presence of a condition that would otherwise account for the degree of pain and dysfunction. According to the International Association for the Study of Pain (IASP), CRPS is divided into two categories based on the absence of a recognizable nerve injury (CRPS type I, formerly known as reflex sympathetic dystrophy) or the presence of a proximal nerve injury (complex regional pain syndrome type II, formerly known as causalgia) (Bruehl et al. 1999). It is often seen in teenage girls and has a greater predeliction for the lower extremity in children when compared to adults (Wilder et al. 1992). Unlike the adult population where there is workman’s compensation etc., the main red flag in children is school absenteeism.