Practical management of complex regional pain syndrome

Abstract

Complex regional pain syndrome (CRPS) describes a diversity of painful conditions following trauma, coupled with abnormal regulation of blood flow and sweating, trophic changes, and edema of skin. The excruciating pain and diverse autonomic dysfunctions in CRPS are disproportionate to any inciting and recovering event. CRPS type I is formerly identified as "reflex sympathetic dystrophy." CRPS type II is the new term for "causalgia" that always coexists with documented nerve injury. The present diagnostic criteria of CRPS I and II depend solely on meticulous history and physical examination without any confirmation by specific test procedure (or gold standard). There are only few clinical studies with large-scale randomized trials of pharmacologic agents on the treatment of CRPS. Bisphosphonates have been studied in multiple controlled trials, based on theoretical benefit of bone resorption, to offer pain relief and functional improvement in patients with CRPS. Many current rationales in treatment of CRPS (such as topical agents, antiepileptic drugs, tricyclic antidepressants, and opioids) are mainly dependent on efficacy originate in other common conditions of neuropathic pain. There are additional innovative therapies on CRPS that are still in infancy. No wonder all the treatment of individual CRPS case nowadays is pragmatic at best. Although the interventional therapies in CRPS (such as nerve blockade, sympathetic block, spinal cord and peripheral nerve stimulation, implantable spinal medication pumps, and chemical and surgical sympathectomy) may offer more rapid response, yet it is still controversial with unpredictable outcome. Nevertheless, we need to start pain management immediately with the ambition to restore function in every probable case of CRPS. An interdisciplinary setting with comprehensive approach (pharmacologic, interventional, and psychological in conjunction with rehabilitation pathway) has been proposed as protocol in the practical management of CRPS. It is crucial to have a high sensitivity value combined with a fair specificity in revising diagnostic criteria of CRPS. The validation and consensus for new rationalized diagnostic criteria of CRPS could facilitate further research to enhance clinical outcome including quality of life. These endeavors to minimize suffering from CRPS would certainly be appreciated by many patients and their loved ones.