Sympathetic Blocks as a Predictor for Response to Ketamine Infusion in Patients with Complex Regional Pain Syndrome: A Multicenter Study.

BACKGROUND: Ketamine infusions are frequently employed for refractory complex regional pain syndrome (CRPS), but there are limited data on factors associated with treatment response. Sympathetic blocks are also commonly employed in CRPS for diagnostic and therapeutic purposes and generally precede ketamine infusions. OBJECTIVES: We sought to determine whether demographic and clinical factors, and technical and psychophysical characteristics of sympathetic blocks are associated with response to ketamine infusion. METHODS: In this multi-center retrospective study, 71 patients who underwent sympathetic blocks followed by ketamine infusions at 4 hospitals were evaluated. Sympathetically maintained pain (SMP) was defined as ≥ 50% immediate pain relief after sympathetic block and a positive response to ketamine was defined as ≥ 30% pain relief lasting over 3 weeks. RESULTS: Factors associated with a positive response to ketamine in univariable analysis were the presence of SMP (61.0% success rate vs 26.7% in those with sympathetically independent pain; P = .009) and post-block temperature increase (5.66 ± 4.20 in ketamine responders vs 3.68 ± 3.85 in non-responders; P = .043). No psychiatric factor was associated with ketamine response. In multivariable analysis, SMP (OR 6.54 [95% CI 1.83, 23.44]) and obesity (OR 8.75 [95% 1.45, 52.73]) were associated with a positive ketamine infusion outcome. CONCLUSIONS: The response to sympathetic blocks may predict response to ketamine infusion in CRPS patients, with alleviation of the affective component of pain and predilection to a positive placebo effect being possible explanations.

Morphological and electrophysiological evaluation of median and ulnar nerve in complex regional pain syndrome type 1.

OBJECTIVE: Complex regional pain syndrome (CRPS) can be distinguished as type I without and type II with electrophysiological evidence of major nerve lesion. The pathophysiology of both subgroups is still under investigation. The aim of this research is to demonstrate the nerve morphology and electrophysiology in CRPS type I patients. MATERIALS AND METHODS: Bilateral median and ulnar nerve cross-sectional areas were evaluated with ultrasound and also median and ulnar nerve conduction studies of both hands were performed. Cross-sectional areas of median and ulnar nerves and nerve conduction studies in healthy controls were also obtained and compared with the patients. RESULTS: Twenty-five male patients and 11 healthy male controls were enrolled in the study. The mean age of the patients was 24.08 ± 5.50 years and controls was 23.18 ± 5.09 (p > 0.05). Compound muscle action potential (CMAP) and sensory nerve action potential (SNAP) amplitudes of the diseased side were found significantly lower than the healthy side (p < 0.05). Both median and ulnar nerve distal motor latency values were significantly higher in the patient group (p < 0.05). There was no significant difference in the median and ulnar nerve cross-sectional area when compared with the opposite extremity and healthy volunteers. CONCLUSION: The lower SNAP and CMAP amplitudes of the median and ulnar nerves compared to the healthy side and the prolongation of the affected side median and ulnar nerve distal motor latencies of the affected individuals may indicate axonal involvement in patients with CRPS type 1. Decreased CMAP amplitudes may also indicate muscle atrophy due to a decrease in the number of functional motor units.

Complex regional pain syndrome.

ABSTRACT: Complex regional pain syndrome (CRPS), formerly called reflex sympathetic dystrophy (RSD), is a chronic pain phenomenon associated with an alteration in peripheral and central pain perception in a localized body region. Because of the many risk factors associated with this phenomenon, the true nature of the disease risk and clinical course are a challenge to predict. After the diagnosis is confirmed and treatment is provided promptly, clinicians must consider patient health and function holistically to foster improvement in overall quality of life.

Successful treatment of complex regional pain syndrome type 1 of upper limb with cryoneurolysis of the stellate ganglion: A rare case report.

Complex regional pain syndrome type I (CRPS I) is a multifactorial condition that is related to neural damage, and leads to chronic neuropathic pain. Due to its multifactorial nature, there are many methods that have been recruited for its management. Most of them limit the symptoms to some degree, but the most effective of them so far seems to be blockade of the sympathetic innervation of the region. We present the case of a 71-year-old woman, with an upper limb fracture which was treated conservatively, and later on developed CRPS type I. Analgesic medications and pregabalin were ineffective in controlling her symptoms. Blockade of the stellate ganglion was performed with local anesthetic and dexamethasone. After the stellate ganglion blockade was marked as successful in relieving her symptoms, cryoneurolysis was performed which was very effective. There are not many cases that have been treated with cryoneurolysis, and this is what makes this case interesting.

Determinants of Diagnostic Delay in Complex Regional Pain Syndrome Type 1: An Observational Study of 180 Consecutive New Cases.

BACKGROUND/OBJECTIVE: Complex regional pain syndrome type 1 (CRPS-1) is a disabling painful disease, with variable outcomes in terms of chronic pain and disability. A long time between onset and diagnosis seems predictive for late recovery and progression toward a chronic disease. This study aims to investigate demographic and clinical variables associated with delayed CRPS-1 diagnosis. METHODS: From March 2013 to January 2018, consecutive patients newly diagnosed according to International Association for the Study of Pain diagnostic criteria for CRPS-1 were recruited. Demographic and clinical variables were collected at diagnosis. Student t test and Mann-Whitney U test were used for comparisons; Cox proportional hazards model was applied to evaluate the variables associated with delayed CRPS-1 diagnosis. RESULTS: One hundred eighty patients entered the study. At diagnosis, women were older, and foot was more often involved than hand. The triggering event was more commonly a trauma without fracture for foot disease and a fracture for hand localization. No differences between hand and foot disease were found by the International Association for the Study of Pain diagnostic categories (clinical vs research) or pain measures. Variables significantly associated with a longer time between disease onset and diagnosis were foot localization, general practitioner referral, higher number of visits before CRPS diagnosis, and prior physiotherapy prescribed for symptoms later diagnosed as CRPS. An overt clinical manifestation (research CRPS-1) predicted a shorter delay. CONCLUSIONS: Foot localization, prior physiotherapy prescribed for symptoms later diagnosed as CRPS, and a disease without overt clinical manifestations were independent predictive factors for a delayed diagnosis. Clinicians should pay attention to these issues to ensure a timely diagnosis and possibly avoid progression toward a chronic disease.

The Tourniquet Ischemia Test in the Diagnosis of Complex Regional Pain Syndrome.

BACKGROUND: The tourniquet ischemia test (IT) is a hitherto rarely used tool for the diagnostic work-up of patients with suspected complex regional pain syndrome (CRPS). This analysis aims to determine the sensitivity and specificity of this test, and elucidate factors that can influence the test result. METHODS: Consecutive data on clinical presentation, results of the IT and other diagnostic tests, and clinical characteristics were analyzed from patients presenting at our autonomic laboratory between 2000 and 2011. IT results were compared with the final clinical diagnosis at discharge, and statistical analysis was performed to determine specificity, sensitivity, and positive and negative predictive values of the IT. RESULTS: A total of 78 patients were assessed. IT results were positive (≥50% reduction in pain during ischemia) in 26 cases and negative in 52 cases. CRPS was the final diagnosis in 45 cases, and in 33 cases, a different diagnosis was made. This results in a test sensitivity of 49% and a specificity of 88%, with a positive predictive value of 85% and a negative predictive value of 56%. Age, sex, the type and stage of CRPS, and the affected extremity did not influence the test result in a statistically significant manner. Specificity worsened to 76% if any pain reduction was rated as a positive test result. CONCLUSIONS: A positive tourniquet IT has a high positive predictive value for the diagnosis of CRPS. It is thus useful as a confirmatory assay in patients with suspected CRPS. Low sensitivity rules out its use as a screening test. SIGNIFICANCE: This study retrospectively analyzed the clinical significance of the tourniquet IT that was routinely used in patients with suspected CRPS. It showed that a positive IT result is useful as a confirmatory assay in patients fulfilling the clinical criteria.

Prognostic Factors in Complex Regional Pain Syndrome Type 1 Occurring in the Korean Army.

OBJECTIVES: In Korea, patients diagnosed with complex regional pain syndrome (CRPS) in the army are typically discharged from the army; however, the course of the disease after discharge is not known. The purpose of this study was to investigate the course of CRPS that occurred in the army and to identify the influences of various clinical and psychosocial factors immediately before discharge on the disease course. METHODS: Clinical profiles and psychosocial status were collected from the medical records of 16 patients with CRPS type 1 who were discharged during the period between March 2017 and April 2018. The degree of improvement after discharge was assessed by follow-up evaluation through telephone contact. Cox proportional hazards regression was performed to identify clinical and psychosocial predictors for the rate of recovery. RESULTS: The median time to recovery after discharge was 39 weeks (95% confidence interval [CI] = 8.8-69.2 weeks). The sole predictor for time to recovery after discharge was the time period from the onset of pain to discharge. Each one-week increase in the duration of pain experienced in the military was associated with a 18.2% (95% CI = 5.3%-29.5%) reduction in the rate of recovery after discharge (P = 0.007). CONCLUSIONS: Patients who experienced a short period of pain in the military demonstrated a relatively good prognosis after discharge. This may show how prolonged pain in the army could affect the experience of pain from a social point of view, in that it shows the disease course after a change in the social environment.

Electroacupuncture for Reflex Sympathetic Dystrophy after Stroke: A Meta-Analysis.

BACKGROUND: Reflex sympathetic dystrophy (RSD) is the common complication among stroke and cerebral injury patients, which is lack of safe and effective treatment. Electroacupuncture (EA) may potentially be a reliably therapy, but the evidence is insufficiency. METHODS: Cochrane Library, MEDLINE, Embase, Chinese National Knowledge Infrastructure, Wan Fang Data, the Chinese Biology Medicine disc, etc., were searched, until July 20, 2018. We included random control trials that contrast EA with conventional rehabilitation therapy for the treatment of RSD. Main outcomes were visual analog scale score and Fugl-Meyer upper limb motor function scoring scale, other outcomes such as Barthel index, and hand swelling score were also collected. Data in included studies were extracted into an excel and pooled by Stata/MP 14.1. RESULTS: We incorporated 13 studies involving 1040 RSD patients and outcomes were from 2 to 6 weeks' follow-up. The analgesic effect between 2 groups had statistically significant difference (weighted mean difference [WMD] = -1.122, 95% confidence interval [CI] [-1.682 to -.562], P = .000], a statistical difference existed in improving dysfunction between 2 groups: (WMD = 6.039, 95% CI [2.231-.916], P = .000). EA groups had a better effect on improving activities of daily life abilities (WMD = 12.170, 95% CI [6.657-17.682], P < .00011] and better detumescence effect (WMD = -.800, 95% CI [-1.972 to -.212], P = .000] contrast to conventional rehabilitation therapy. CONCLUSIONS: This meta-analysis supports that EA has a positive effect on alleviating pain, improving limb dysfunction, and promoting activities of daily living. On account of moderate-quality random control trials and high heterogeneity, further high-quality studies are imperative to optimize the EA treatment program.

The Effectiveness of Fluidotherapy in Poststroke Complex Regional Pain Syndrome: A Randomized Controlled Study.

OBJECTIVE: To evaluate whether combining fluidotherapy to conventional rehabilitation program provides additional improvements on pain severity, upper extremity functions, and edema volume in patients with poststroke complex regional pain syndrome (CRPS). DESIGN: Randomized controlled trial. SETTING: Training and research hospital. PARTICIPANTS: Thirty hemiplegic patients with subacute stage CRPS type-1 of the upper extremity. INTERVENTIONS: The patients randomly divided into 2 groups. Both groups received a 3 week conventional rehabilitation program (5 days/week, 2-4 hours/day). Experimental group received 15 sessions additional fluidotherapy application to the affected upper extremity (40 °C, 20 minutes in continuous mode, 5 sessions/week). MAIN OUTCOME MEASURES: We evaluated the distal upper arm edema with a volumeter. Other used clinical assessment scales were Brunnstrom recovery stages of the arm and hand for motor recovery, motor items of the functional independence measure for functional status, visual analog scale for pain severity, and the painDETECT questionnaire for presence and the severity of neuropathic pain. RESULTS: The mean age of the participants was 64.3 ± 11.66 (28-84). At the post-treatment evaluation, significant improvements were revealed regarding to the edema volume, pain visual analog scale, painDETECT and functional independence measure scores, and the Brunnstrom stages of upper extremity and hand in both groups (P < .05). But among the parameters mentioned above, only the decrease in edema volume and the painDETECT scores were greater in fluidotherapy group than the control group (P < .05). CONCLUSIONS: Addition of the fluidotherapy to the conventional rehabilitation program provides better improvements on neuropathic pain and edema volume in subacute stage poststroke CRPS.

Bisphosphonates in the treatment of complex regional pain syndrome: is bone the main player at early stage of the disease?

Complex Regional Pain Syndrome type 1 (CRPS-1) is a disabling painful disease whose hallmark is pain disproportionate to inciting event. CRPS is also characterized by symptoms and signs, such as vasomotor, sudomotor, trophic and motor changes. Therapeutic approach of CRPS-1 still remains a challenge for clinicians treating a disease with potential heavy consequences on patient prognosis. In the past years, the treatment with bisphosphonates (BPs) has gained some success as confirmed by the results of a number of meta-analyses. The aim of this paper is to point out the pivotal role of bone in CRPS pathogenesis. The efficacy of BPs is likely to be related to bone tissue involvement in the early pathophysiological steps of the disease, as demonstrated by evidences highlighting the central role of bone in the initial phases. Bone can become a source of inflammatory cytokines when triggered by a direct injury. Moreover, peptidergic fibers that innervate both mineralized bone and bone marrow can play a role in triggering or maintaining the microvascular disturbance at bone level. Indeed, bone involvement is consistent with the mineralization disturbance as well as the results of instrumental investigations (e.g., MRI, bone scan). In this regard, an intriguing issue relies on the excellent therapeutic response to BPs treatment of other diseases (e.g., Transient Osteoporosis of the Hip and Regional Migratory Osteoporosis) that share with CRPS-1 some clinical and instrumental features.

Predictors of Responsiveness to Bisphosphonate Treatment in Patients with Complex Regional Pain Syndrome Type I: A Retrospective Chart Analysis.

Objective: The aim of this study was to assess whether the effectiveness of bisphosphonate infusion in patients with complex regional pain syndrome type I (CRPS-I) is influenced by variables related to patient and/or disease characteristics. Methods: This is a retrospective analysis of patients referred in the last five years to our rheumatologic tertiary care center, all fulfilling the Budapest CRPS-I diagnostic criteria and treated with three different bisphosphonate schedules (clodronate, pamidronate, and neridronate). For every subject, demographic and clinical variables were retrieved and retrospectively analyzed. We identified variables that independently influenced the therapeutic outcome of patients by a logistic regression analysis. For exploratory purposes, the effectiveness of the different bisphosphonate treatments employed was compared. Results: Among the 194 patients included in the analysis, the overall therapeutic response rate was 71.6%. Logistic regression analysis showed that the independent predictive variables for therapeutic effectiveness were disease duration (odds ratio [OR] = 0.83, 95% confidence interval [CI] = 0.72-0.96 for a one-month increment), fracture as a predisposing event (OR = 3.23, 95% CI = 1.29-8.03), and "warm" disease subtype (OR = 4.88, 95% CI = 1.57-15.20). These variables were found to influence the odds of responsiveness when analyzed together with age at onset, gender, and disease localization. No significant difference in therapeutic effectiveness was found by comparing the three different bisphosphonate schedules employed. Conclusion: Early disease, fracture as a predisposing event, and "warm" disease subtype are predictors of responsiveness to bisphosphonate treatment in patients with CRPS-I.

[Reliability of venous blood gas analysis and radionuclide angiography in post-traumatic dystrophy]. / Reliabilität der venösen Blutgasanalyse und Radionuklidangiographie bei Posttraumatischer Dystrophie.

BACKGROUND: The diagnosis "post-traumatic dystrophy" (PTD) was first defined with clinical and paraclinical criteria by Scola et al. in 2013. OBJECTIVES: The objectivity and reliability of the paraclinical criteria (venous blood gas analysis [vBGA], radionuclide angiography [RNA]), and recommendations for therapy should be assessed in a prospective study. MATERIALS AND METHODS: In five patients with clinical signs of post-traumatic nonbacterial inflammation of the hand, both diagnosis and a 3­week hospital treatment were carried out in accordance with the publication mentioned above. The primary traumata (four fractures and one soft-tissue injury) were located in either the hand or the forearm. Unsuccessful outpatient treatment always led to hospital admission. One patient with severe osteopenia in the hand skeleton was treated with bisphosphonates for 6 months. RESULTS: All patients fulfilled the clinical and paraclinical criteria for the diagnosis of PTD. On admission, an elevated venous partial pressure of oxygen was found by vBGA in the affected hand (∆pO2 mean 22 ± 3 mm Hg) and a hyperperfusion due to arteriovenous shunts was measured using RNA (mean 75 ± 47%). The symptomatic treatment was extremely well tolerated; by the time of discharge, all patients achieved full functioning of the hand with minor loss of strength (venous ∆pO2 mean 5 ± 3 mm Hg). The osteopenia in the one patient treated with bisphosphonates showed recalcification after 6 months. CONCLUSION: The reliability of clinical and paraclinical criteria for PTD were confirmed. vBGA and RNA seem to be good parameters for confirming the diagnosis of PTD. "Rubor," a symptom traditionally interpreted as "hyperemia," contradicts the paraclinical findings and leads to the assumption that the cause of this post-traumatic syndrome is microvascular dysfunction.

Management of patients with complex regional pain syndrome type I.

Complex regional pain syndrome type I (CRPS-I) includes different conditions characterized by regional pain and sensory, motor, sudomotor, vasomotor, and/or trophic findings, affecting a peripheral limb usually after a noxious event, such as a trauma or surgery. The pathophysiology is still poorly understood. Limited data are available on the incidence of CRPS-I, and the disease is underestimated and under-diagnosed. The disease shows a female preponderance approximately 3:1 with a peak age of incidence around the 5th and 6th decade. The available diagnostic criteria for CRPS-I rely on clinical criteria that are unfortunately focused on the signs and symptoms of the chronic and late disease, while little emphasis is given to the typical imaging (X-rays, bone scintigraphy, MRI) findings of the early phase. Over the last decades, several therapies have been proposed but the few studies available are often too small to be conclusive and rarely evolved to randomized controlled trials (RCTs). On the basis of the results of a few RCTs, only short courses of high bisphosphonate doses appear to provide substantial benefits. The best results are seen in patients in the early phase of the disease, often with the persistent remission or complete healing of the conditions. Since the only accredited mechanism of action of bisphosphonates is the suppression of osteoclastic bone resorption, it is likely the initial dramatic bone loss plays a role in the maintenance and evolution of CRPS-I. Short courses of high doses of bisphosphonates should be considered the treatment of choice for patients with CRPS-I.

Musculoskeletal Ultrasonography to Distinguish Muscle Changes in Complex Regional Pain Syndrome Type 1 from Those of Neuropathic Pain: An Observational Study.

Musculoskeletal ultrasonography (MSK USG) can identify myofascial structural lesions. We describe in this retrospective report the observational findings of USG data of muscles from limbs affected with neuropathic pain in 7 patients and compare them with muscles affected with complex regional pain syndrome type 1 (CRPS-1) in 7 patients. We highlight findings that distinguish between the 2 conditions. Musculoskeletal ultrasonography of muscles in CRPS was characterized by a variable or/and global intramuscular structural disruption with loss of muscle bulk. Adjacent muscles coalesced with one another to present an uniform hyperechogenic mass of tissue. Muscle edema was found in some patients. In comparison, MSK USG in muscles affected by neuropathic pain exhibited structural normalcy, but also showed considerable reduction in muscle bulk. Musculoskeletal ultrasonography shows promise as a diagnostic modality to distinguish between these 2 conditions which presently have only clinical diagnostic criteria to aid diagnosis.

Skin sympathetic function in complex regional pain syndrome type 1.

PURPOSE: Cutaneous sympathetic pathophysiology in complex regional pain syndrome type 1 (CRPS-1) is not yet completely understood. To evaluate cutaneous sympathetic dysfunction in CRPS-1, we evaluated sympathetic sweat response (SSwR) and skin vasomotor reflex (SkVR) in CRPS-1 patients. METHODS: We studied 10 CRPS-1 patients (age 41 ± 13 years; 5 females and 5 males; disease duration 20 ± 22 months) and 10 healthy subjects (age 44 ± 13 years; 3 females and 7 males). SkVRs and SSwRs to several sympathetic activating procedures were recorded on the palms of the CRPS-1 patients (affected side) and controls (right side). RESULTS: There were no significant differences in the baselines of sweat output and skin blood flow between the CRPS-1 and control groups. SSwR and SkVR amplitudes were significantly lower in the CRPS-1 group than in the control group. There was no significant correlation between disease duration and SSwR or SkVR amplitudes among the patients. CONCLUSIONS: The reduced SSwRs and SkVRs in the affected limb of our CRPS-1 patients may reflect underlying damage to the sympathetic postganglionic fibres.

Complex regional pain syndrome type I: a comprehensive review.

BACKGROUND: Complex regional pain syndrome type I (CRPS I), formerly known as reflex sympathetic dystrophy (RSD), is a chronic painful disorder that usually develops after a minor injury to a limb. This topical review gives a synopsis of CRPS I and discusses the current concepts of our understanding of CRPS I in adults, the diagnosis, and treatment options based on the limited evidence found in medical literature. CRPS I is a multifactorial disorder. Possible pathophysiological mechanisms of CRPS I are classic and neurogenic inflammation, and maladaptive neuroplasticity. At the level of the central nervous system, it has been suggested that an increased input from peripheral nociceptors alters the central processing mechanisms. METHODS: A literature search was conducted using, as electronic bibliographic database, Medline from 1980 until 2014. RESULTS: An early diagnosis and multidisciplinary treatment are necessary to prevent permanent disability. CONCLUSIONS: The pharmacological treatment of CRPS I is empirical and insufficiently effective. Further research is needed regarding the therapeutic modalities discussed in the guidelines. Physical therapy is widely recommended as a first-line treatment. The efficacy of local anesthetic sympathetic blockade as treatment for CRPS I is questionable.

Bisphosphonates in Complex Regional Pain syndrome type I: how do they work?

Complex Regional Pain syndrome type I (CRPS-I) is a disease characterised by extreme pain for which no gold-standard treatment exists to date. In recent years a possible role for bisphosphonates in the treatment of CRPS-I has been proposed. These drugs were first used for their effect in decreasing pain in bone diseases in which bisphosphonates act through their antiosteoclastic properties (metastatic disease, Paget disease, myeloma). In CRPS-I, enhanced osteoclastic activity has never clearly been demonstrated and the benefit shown is possibly exerted by different mechanisms of action. In this paper we review other conjectural mechanisms involved in reducing pain intensity and improving clinical signs and functional status in these patients. The results of most studies on this topic show that bisphosphonates may be effective in the early phases of the disease, when scintigraphic bone scan more frequently shows a local radiotracer accumulation that possibly means a high local concentration of the drug. These features probably represent the required conditions by which bisphosphonates might modulate various inflammatory mediators that are upregulated in CRPS-I. Patients in whom a scintiscan is often negative (long-standing disease or a primarily cold disease) could be less responsive to this treatment. With these limitations, bisphosphonates appear to present a therapeutic strategy that has been proven to reliably offer benefits in patients with CRPS-I.

Factors associated with complex regional pain syndrome type I in patients with surgically treated distal radius fracture.

PURPOSE: Wrist fracture is considered a typical initiating trauma for complex regional pain syndrome type I (CRPS I). However, few studies have comprehensively evaluated factors associated with the occurrence of CRPS I after the surgical treatment of a distal radius fracture (DRF). This study evaluates the factors influencing the occurrence of CRPS I after the surgical treatment of a DRF. METHODS: A total of 477 patients with a DRF who had been treated surgically were enrolled in this prospective observational study. Patients were followed for 6 months after surgery, and CRPS I was diagnosed using the Budapest diagnostic criteria for research. The factors assessed for the development of CPRS I were age, gender, the body mass index, the type of fracture, the energy of trauma, the number of trial reductions, the type of surgery, and the duration of immobilization. A multivariate logistic regression analysis was conducted to identify independent predictors of the occurrence of CRPS I. RESULTS: Among the 477 patients, 42 (8.8 %) satisfied the Budapest criteria for CRPS I within 6 months of surgery. Female patients developed CRPS I more frequently, and the patients who developed CRPS I were older and more likely to sustain a high energy injury or have a comminuted fracture. According to the multivariate analysis, female patients and those with a high energy trauma or severe fracture type were significantly more likely to develop CRPS I (p = 0.02, 0.01, and 0.01, respectively). CONCLUSIONS: High energy injuries, severe fractures, and the female gender contribute to the development of CRPS I after the surgical treatment of DRF. The results have important implications for physicians who wish to identify patients at high risk for CRPS I after operative fixation for DRF and instigate treatment accordingly.

Sympathomimetic amine therapy found effective for treatment of refractory chronic complex regional pain syndrome (reflex sympathetic dystrophy).

PURPOSE: To determine if treatment with sympathomimetic amines could improve the pain from complex regional pain disorder (CRPD) which was keeping a woman from trying to conceive her second child. MATERIALS AND METHODS: Dextroamphetamine sulfate was prescribed. RESULTS: Within a short length of time the woman's wrist pain considerably improved to the point that she is ready to try in vitro fertilization once again to have a second baby. CONCLUSIONS: Though sympathomimetic amines are used by some reproductive endocrinologists for unexplained infertility and unexplained recurrent miscarriages, the most common use by the gynecologist is for pelvic pain. Despite the thought by some clinicians and researchers that the etiology for CRPD may be related to sympathetic nervous system hyperactivity (and thus sympathomimetic amines could theoretically exacerbate the symptoms), in fact, the treatment with dextroamphetamine sulfate may turn out to be a new and possibly the most effective, least risky, and least expensive treatment to date for CRPD.