Complex regional pain syndrome type I

Abstract

Complex regional pain syndrome type I (CRPS) is a painful and disabling syndrome of unknown pathophysiology that may occur spontaneously or after trauma or surgery to a limb. Over the last two decades, the theories about the cause and treatment of CRPS have been based increasingly on evidence from controlled trials instead of being in uenced by anecdotal case reports.The literature on CRPS was reviewed. With regard to treatment, the review was based on controlled studies reported during the period 1979-1999. At present, there is still only limited understanding of the pathophysiology of CRPS. However, the key to its causes is likely to be that, in certain individuals, peripheral nerve injury leads to the development of maladaptive compensatory changes in both the peripheral and central nervous systems. Recent studies have indicated that speci c human leucocyte antigen alleles are associated with CRPS, suggesting that certain individuals may be at risk of its development. On the other hand, the incidence of CRPS after trauma can be reduced by supplementation with vitamin C. Treatment is based on physiotherapy together with medication that reduces neuropathic pain. Blocking the sympathetic nervous system is ineffective in most patients. In chronic cases, electrical stimulation of the nervous system (transcutaneous or direct stimulation of peripheral nerves or the spinal cord) effectively reduces pain in more than half of those patients in whom alternative therapies have failed.There has at last been some progress in our understanding of the pathophysiology and treatment of CRPS. Currently, however, prevention (vitamin C after trauma) still seems the best option.