The syndrome of Reflex Sympathetic Dystrophy (RSD)¹ a variant of Complex Regional Pain Syndrome is a diagnosis reliant principally upon clinical evaluation, routine radiographs² characteristic scintograph pattern of Technetium 99m labeled diphosphonates and/or MR imaging ; Laser Doppler flowmetry may support the diagnosis³. According to the Special Interest Group of Pain and the Sympathetic Nervous System of the International Association for the Study of Pain, a sympathetic nerve block is the most important diagnostic resource for distinguishing RSD from SMP (Sympathetically Maintained Pain^)4. Causalgia and RSD may be independent of the sympathetic efferent enervation, and in advanced cases, the course of RSD pain frequently becomes sympathetically independent (SIP). The clinical paradigm noted in many such podiatric cases would follow the reasoning that three-phase bone scanning is a generally considered a valuable adjunct to clinical judgment in making the proper diagnosis. Complex regional pain According to Nath RK et. al. (1996) sympathetically maintained pain exists but that it may comprise only approximately 10% of regional pain cases⁵ De Takats⁶ and Bonica⁷ defined the three stages of RSD (I-III). And Blumberg, Greisser and Hornyak⁸ classified the clinical symptoms of RSD into three categories (autonomic, motor and sensory). It is my understanding that a patient generally be appointed with a physician specializing in anesthesia/pain management at one point in time and that such an evaluation may include a diagnostic lumbar spinal block followed by a diagnostic sympathetic lumbar spinal block under fluoroscopy. The results of such an evaluation will be of significant interest in terms of verifying the Complex Regional Pain diagnosis and establishing with medical reasonableness the boundaries of prospective medical treatment and in defining the patient’s status.                        

                             NERVUS  TRUNCUS SYMPATHICUS                 

  "One glorious hour of conquering strife is worth an age of quiet peace."
        Shakespeare.

*Sympathetic Nerve 60X Hematoxylin and eosin stain.

^[1]International Association for the Study of Pain Subcommittee on Taxonomy:  Classification of Chronic Pain.  Descriptions of chronic pain syndromes and definitions of pain terms.  (105), Pain (supp.) '29-'30, 1986

^[2]Sintzoff S et. al.,  Imaging in reflex sympathetic dystrophy, Hand Clin, 13(3):431-42 1997 Aug.

^[3]Gordon N, Reflex sympathetic dystrophy,  Brain Dev, 18(4):257-62 1996 Jul-Aug

^[4]The syndrome of SMP is associated with a physical trauma to the painful area, and Acontinuous burning pain together with mechanical allodynia@.  With SMP, relief of only one component of the pain-symptom with sympathetic lumbar block is usually obtained.  This indicates a localized disorder and the involvement of a well-defined sympathetically mediated effector pathway and reflects dependence of the disorder upon the activity of an intact sympathetic efferent/catecholamine outflow.  This finding would mitigate against a diagnosis of RSD.

^[5]Nath RK Reflex sympathetic dystrophy. The controversy continues,. Clin Plast Surg, 23(3):435-46 1996 Jul

^[6]De Takats, G. Reflex dystrophy of the extremities.  Arch. Surg. 34:939-956, 1937.

^[7]Bonica, J.J. Causalgia and other reflex sympathetic dystrophies. Ch. 11 In The management of Pain, 2nd Ed., pp. 220-243, Lea & Frebiger, Philadelphia, 1990.

 ^[8]Blumberg, H., Griesser, H.J., Hornyak, M.E. Mechanisms and role of peripheral blood flow disregulation in pain and edema of reflex sympathetic dystrophy.  Ch. 10 In Reflex Sympathetic Dystrophy, pp. 81-95 ed. M. Stanton-Hicks, W. Janig, R.A. Boas, Kluwer Academic Publisher, Boston 1990.