Reflex sympathetic dystrophy: a multidisciplinary approach.

Abstract

Reflex sympathetic dystrophy (RSD) is a complex regional pain syndrome characterized by variable dysfunctions of the musculoskeletal, skin, and vascular systems. The most common features are severe persistent spontaneous pain in a limb, sensory and vascular alterations, and major associated disability, which often causes profound psychological dysfunction (1,2). RSD is characterized by spontaneous pain, swelling, dysaethesia, and allodynia usually of a distal site of the affected extremity (3,4). Other features relate to the autonomic nervous system and include cyanosis, mottling, sweating (which is less common in children), and reduction in temperature. In some cases, particularly if there is delay in recognition or treatment, more permanent or serious features may develop; these include muscle atrophy, demineralization of bone, and contractures of soft tissue around the affected joint. In the early stages of RSD, there are no specific laboratory tests available to help diagnose the condition, and the radiologic and bone scanning findings characteristic in adults are often not seen in children (5–9). The lack of diagnostic investigations, the relative lack of recognition of the condition, and the more variable clinical presentation present in children often result in a delay in diagnosis and treatment. This often is complicated by the diversity of medical opinions sought from the onset of symptoms. This may lead to a more severe and chronic presentation. Although a number of studies have reported RSD in childhood, a variety of approaches to its management have been suggested with variable or undetermined outcomes (10). RSDmay also occur in, or be associated with, a variety of other clinical conditions and may affect different areas of the body to a greater or lesser extent. There are also a variety of descriptive names that are used as synonyms for RSD, including algodystrophy, reflex neurovascular dystrophy, causalgia, Sudeck’s atrophy (although this refers to patients with the classic macular osteopenia, not often seen in children), and complex regional pain syndrome type 1 (2). In this article we prefer the older but perhaps still more commonly used term, RSD (11–13). Population studies in schoolchildren indicate that chronic or recurrent musculoskeletal pain is quite common, with back pain being the most frequent (20%), followed by limb pain (16%) and fibromyalgia (6%) (14–17). There is little work on the incidence of RSD, but 5–8% of new referrals to North American pediatric rheumatology centers have a diagnosis of idiopathic musculoskeletal pain syndromes, a small percentage of which are RSD (18,19). Idiopathic musculoskeletal pain syndromes have been described in patients as young as 3 years of age, though RSD has not been reported at this age. The majority of reports involve children in late childhood or early adolescence, with a mean age of onset of 12–13 years and a higher frequency in girls than boys ( 4:1) (3,4,13,20–22). There have been no reports of specific ethnic differences in the presentation of RSD. Currently, there is no single or specific biologic cause identified or pathogenetic pathway described for RSD, and it is clear that the clinical features may vary widely from children to adults. The etiology is likely to be multifactoral in some children. In many pediatric cases, however, there is no or only a very minor precipitating incident; psychological factors may have greater influence. This hypothesis is supported with the differences found between technetium bone scintigraphy in children compared with adults and by the fact that children respond more readily to physical therapies (4,23). However, it appears that the triggering factor in many children is related to injury, illness, or psychological distress in any combination (3–5,8,9,13–17,20,24–39), in contrast to adults in whom surgery or myocardial infarction often precedes the onset of RSD (31,32,40). Susan M. Maillard, MSc, SRP, MCSP, Karen Davies, MB, BS, MRCP, Patricia M. Woo, MB, BS, PhD, FRACP, Kevin J. MurrayMB, BS, FRACP (current address: Princess Margaret Hospital for Children, Perth, Western Australia): Great Ormond Street Hospital for Children NHS Trust, London, United Kingdom; Raju Khubchandani, MD, FRACP: Jaslock Hospital and Research Centre, Mumbai, India. Address correspondence to Susan M. Maillard, MSc, SRP, MCSP, Juvenile Dermatomyositis Research Centre, Rheumatology Unit, Ground Floor, Philip Ullmann Wing, 30 Guilford Street, London, WC1N 1EH, United Kingdom. Email: S.Maillard@ich.ucl.ac.uk. Submitted for publication March 31, 2003; accepted in revised form September 15, 2003. Arthritis & Rheumatism (Arthritis Care & Research) Vol. 51, No. 2, April 15, 2004, pp 284–290 DOI 10.1002/art.20249 © 2004, American College of Rheumatology