The pathomechanisms involved in both restless legs syndrome (RLS) and complex regional pain syndrome type I(CRPS I) are still controversial whether they are central or peripheral origins. We recently encountered a patient whohad an unusual coexistence of both RLS and CRPS I, and both of which showed good responses to sympathetic block.These findings suggest the role of peripheral mechanisms, especially unmyelinated small autonomic fiber, in both RLSand CRPS I
