Patients who display variations or permutations of such general clinical profile may harbor organic structural neurological damage or a somatoform pseudoneurological disorder, fraudulent malingering, the bizarre Munchausen’s condition, or a borderline personality with associated self-infliction of physical damage. Unfortunately, litigation and compensation issues tend to perpetuate both complaints and medical management, as the psychobiosocial scenario may become contaminated with secondary gain agendas from the patient and tertiary gain from health care providers or lawyers.

Various treatment modalities may dramatically relieve the subjective or psychophysical reflex sympathetic dystrophy (RSD) symptoms. Unfortunately, recurrence or “metastases” are almost the rule. Placebo response was never factored into the “diagnostic-therapeutic block” paradigm until the last decade. Iatrogenesis is inevitably part of the management outcome of RSD/complex regional pain syndrome (CRPS) patients. It is an error to assume that patients who display the clinical profile of RSD/CRPS have a discrete disease with one common etiology and definable pathophysiological mechanism leading to neurological manifestations. They merely harbor a nonspecific symptom complex with any possible variety of abnormal physiological or psychological backgrounds. It is a classic fallacy to assume that behind these patients’ pains and motor and sensory symptoms, there is a unique abnormal mechanism by which the sympathetic system causes not only the objective circulatory changes but also, indirectly, the painful neurological dysfunction. Errors include historical misinterpretation of vasomotor signs in symptomatic body parts and misconstruing symptomatic relief after “diagnostic” sympathetic blocks, due to lack of consideration of the placebo effect which explains the outcome. It is also not true that sympatholysis may specifically cure patients with unqualified “RSD.”

As extrapolated from observations in animals with gross experimental nerve injury, adducing hypothetical, untestable, secondary central neuron sensitization to explain psychophysical sensory-motor complaints displayed by patients with blatantly absent nerve fiber injury is not an error, but a lie. While conceptual errors are not only forgivable but natural to inexact medical science, lies, particularly when entrepreneurially inspired, are condemnable and call for peer intervention.

Journal: J Neurol, 246(10):875-9, 1999. 38 References
Reprint: Department of Neurology, Good Samaritan Hospital and Oregon Health Sciences University, 1040 NW 22nd Ave N-460, Portland, OR 97210 (JL Ochoa, MD)

Concerning diagnosis, no specific test is available for CRPS, and no pathognomonic clinical feature identifies this condition. Rather, identifying a constellation of history, clinical examination, and supporting laboratory findings make the diagnosis. Most patients with CRPS have an identifiable inciting or initiating injury, which may be trivial or severe. The key features are pain, allodynia and hyperalgesia, abnormal vasomotor activity, and abnormal sudomotor activity persisting beyond the period of normal healing. Pain usually spreads beyond the area of the initial injury and, in its most severe form, may involve the entire limb and, rarely, the contralateral limb.

Symptoms of sympathetic dysfunction may be present and may manifest as vasomotor and/or sudomotor instability. The symptoms typically come and go and, in later stages, may not be present at the time of the initial examination. The typical signs are color changes, temperature changes, and excessive sweating. Hyperhidrosis is a common finding early in the course of CRPS. If pain is relieved by sympathetic blockade, it is regarded as sympathetically maintained. Pain that is not relieved by sympathetic blockade is known as sympathetically independent pain. Sympathetically maintained pain can convert to sympathetically independent pain and, in the authors' experience, "pure" sympathetically maintained pain is rare. Patients who have had symptoms for months to years may have severe brawny edema, muscle atrophy and contractures, and marked cyanosis of the limb. Treatment at this late stage is often unsuccessful.

Although no specific diagnostic test is available for CRPS, several tests can be supportive in making the diagnosis. The most important role of testing is to help rule out other conditions. Some of the testing used includes vascular studies, electrodiagnostic studies, radiographic studies, and blood tests. Plain radiographs can show patchy osteoporosis as early as two weeks after the onset of CRPS.

At present, sympathetic blocks, once considered essential in the diagnosis, are not required to be positive for a diagnosis of CRPS. Since some patients do not have sympathetic dysfunction, it is important to identify them because of therapeutic implications. A pharmacological sympathetic block can be performed with an intravenous infusion of phentolamine; however, this technique has not gained widespread use. The more common and time-tested approach is to perform a local anesthetic sympathetic trunk block: a lumbar paravertebral sympathetic block for the lower extremity and a stellate ganglion block or upper thoracic sympathetic block for upper extremity symptoms. Although it is vital to obtain evidence of satisfactory sympathetic block and to demonstrate the absence of somatic nerve block for diagnosis, occasionally in treatment sympathetic and somatic block may be necessary for advanced disease.

Successful treatment of CRPS depends on an aggressive and multidisciplinary approach. Since pain and limb dysfunction are the major clinical problems, physical rehabilitation and pain control are the main treatment objectives. Comorbidities such as depression, sleep disturbance, anxiety, and generalized physical deconditioning should be treated. This means that a patient's pain and disability must be treated in a manner that allows rehabilitation to proceed. Drug therapy, including anti-depressant agents, gabapentin, corticosteroids, topical analgesics, opioids, and other drugs, has been used successfully. Regional anesthesia techniques, including sympathetic blocks and somatic blocks, are required in some cases. Neuromodulation, including spinal cord stimulation and intrathecal analgesia, have been used. Intrathecal baclofen has been shown to decrease the dystonia, improve functioning, and occasionally reduce pain levels.

Like most medical conditions, early diagnosis and treatment of CRPS increase the likelihood of a successful outcome. Accordingly, patients with clinical signs and symptoms of CRPS after an injury should be referred as soon as possible to a physician with expertise in evaluating and treating this condition. Mild cases respond to physical therapy and physical modalities. Mild to moderate cases may require adjuvant analgesia, such as gabapentin and/or an anti-depressant medication. An opioid should be added to the treatment regimen if these medications do not provide sufficient analgesia. Patients with moderate to severe pain and/or sympathetic dysfunction require regional anesthetic blocks to participate in physical therapy. Most patients improve with early treatment. A small percentage of patients develop refractory, chronic pain and require long-term multidisciplinary treatment, including physical therapy, psychological support, and pain relieving measures. A suggested treatment algorithm is given.

Journal: Mayo Clin Proc, 77(2):174-180, 2002. 10 References
Reprint: Div of Pain Medicine, Mayo Clinic, 200 First St SW, Rochester, MN 55905 (RH Rho, MD)

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