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.

Utilization of Concurrent Dorsal Root Ganglion Stimulation and Dorsal Column Spinal Cord Stimulation in Complex Regional Pain Syndrome.

INTRODUCTION: Complex regional pain syndrome (CRPS) can be effectively treated with spinal cord stimulation (t-SCS). There is also evidence that dorsal root ganglion (DRG) stimulation may be superior to t-SCS in CRPS. However, there has been no published data, to our knowledge, that looked at the concurrent use of t-SCS and DRG stimulation for treatment of CRPS. METHODS: Our study includes four patients with severe CRPS who had all been implanted with a t-SCS. While all these patients had positive results from their t-SCS, they all had areas which lacked coverage, giving them incomplete pain relief. These patients also underwent successful trial and implantation of DRG-S. All four patients reported further improvement in their residual pain and function with DRG-S (>60%), and even superior pain relief (>80%) with concurrent use of t-SCS and t-SCS. RESULTS: All patients had a diagnosis of lower extremity CRPS-1. After DRG-S implantation, multiple attempts were made in each patient to use DRG-S alone by temporarily turning the t-SCS off. However, in each attempt, all patients consistently reported superior pain relief and improvement in function with the concurrent use of t-SCS and DRG, as compared to DRG alone. The average numeric rating scale pain score decreased from approximately 7 in the regions not covered by t-SCS to 3 after DRG-S implantation, and to 1.25 with concurrent use t-SCS and DRG-S. CONCLUSION: Both t-SCS and DRG-S have been shown to be effective in treatment of patients with CRPS. In our study, concurrent use of t-SCS and DRG-S provided significant improvement in pain and function as compared to using either device alone. This suggests the potential that combination therapy with t-SCS and DRG-S may be beneficial in patients with CRPS. Further prospective studies are required to evaluate this concept.

Direct Peripheral Nerve Stimulation for the Treatment of Complex Regional Pain Syndrome: A 30-Year Review.

INTRODUCTION: Complex regional pain syndrome (CRPS), formerly known as reflex sympathetic dystrophy (RSD), is a difficult to treat condition characterized by debilitating pain and limitations in functional ability. Neuromodulation, in the form of spinal cord stimulation (SCS) and peripheral nerve stimulation (PNS), have been traditionally used as a treatment for CRPS with variable success. OBJECTIVE: This chart review describes the use of implantable PNS systems in the treatment of CRPS of the upper and lower extremities spanning nearly three decades. MATERIALS AND METHODS: A retrospective chart review was performed on 240 patients with PNS implanted between 1990 and 2017 at our institution. Of these, 165 patients were identified who had PNS systems implanted for a diagnosis of CRPS. Patient profile, including baseline characteristics, comorbidities, past/current interventions/medications and targeted nerves, was descriptively summarized through standard summary statistics. Patients' pain scores and opioid consumptions at baseline (preimplant), 1 month, 6 months, and 12 months were collected and compared. Device revisions and explants were summarized, and patient functional outcomes were described. RESULTS: Pain scores at baseline and at 12-month follow-up were decreased from a mean of 7.4 ± 1.6 to 5.5 ± 2.4 and estimated to be 1.87 (95% CI: [1.29, 2.46], paired t-test p-value <0.001) lower at 12 months. At baseline, 62% of patients were on chronic opioid therapy, compared with 41% at 12 months. Of 126 patients who reported changes in functional status, 64 (51%) reported improvement, 27 (21%) reported worsening, and 35 (28%) did not report any meaningful change. Excluding end-of-life battery replacements, surgical revision occurred in 56 (34%) of patients. Thirteen patients (8%) underwent implantation of a second PNS because of symptomatic expansion outside of the original painful region. Device explant was performed in 32 (19%) of patients. Median length of follow-up was 74 [14, 147] months. Of the 36 patients who continue to follow-up at our institution, 29 (81%) continue to use their PNS. CONCLUSIONS: We can conclude that PNS is a useful modality to improve function and reduce long-term pain in selected patients suffering from CRPS type I and type II.

Socioeconomic Disparities in the Utilization of Spinal Cord Stimulation Therapy in Patients with Chronic Pain.

OBJECTIVES: Spinal cord stimulation (SCS) therapies are used in the management of patients with complex regional pain syndrome I (CRPS I) and failed back surgery syndrome (FBSS). The purpose of this study was to investigate the racial and health insurance inequalities with SCS therapy in patients with chronic pain who had CRPS I and FBSS. METHODS: Patients with chronic pain who had a discharge diagnosis of FBSS and CRPS I were identified using the National Inpatient Sample database. Our primary outcome was defined as the history of SCS utilization by race/ethnicity, income quartile, and insurance status. Multivariable logistic regression was used to determine the variables associated with utilization of SCS therapy. RESULTS: Between 2011 and 2015, 40,858 patients who were hospitalized with a primary diagnosis of FBSS and/or CRPS I were identified. Of these patients, 1,082 (2.7%) had a history of SCS therapy. Multivariable regression analysis revealed that compared to White patients, Black and Hispanic patients had higher odds of having SCS therapy (Black patients: odds ratio [OR] = 1.41; 95% confidence interval [CI], 1.12 to 1.77; P = 0.003; Hispanic patients: OR = 1.41; 95% CI, 1.10 to 1.81; P = 0.007). Patients with private insurance had significantly higher odds of having SCS therapy compared with those with Medicare (OR = 1.24; 95% CI, 1.08 to 1.43; P = 0.003). Compared to patients with Medicare, Medicaid patients had lower odds of having SCS therapy (OR = 0.50; 95% CI, 0.36 to 0.70; P < 0.001). CONCLUSIONS: Our study suggests that socioeconomic disparities may exist in the utilization of SCS among hospitalized patients with CRPS I and FBSS the United States. However, confirming these data from other administrative databases, in the outpatient setting, may shed more insight.

Evaluation Through Transcutaneous Tissue Oximetry (Near Infrared Spectroscopy) of Spinal Cord Stimulation in Patients With Complex Regional Pain Syndrome Type I.

OBJECTIVE: One of the physiopathological hypothesis behind complex regional pain syndrome (CRPS) type I involves the deep-tissue hypoxia of the affected areas. Spinal cord stimulation (SCS) appears to be effective in the treatment of these patients. We evaluated whether ESCS modifies tissue oxygen saturation (StO2 ) measured with near-infrared spectroscopy (NIRS) in the affected limbs in patients diagnosed with CRPS type I. MATERIALS AND METHODS: Nonrandomized, cross-sectional study that evaluated 16 patients with CRPS type I who were receiving SCS applied to the posterior cords. NIRS was used to evaluate baseline StO2 (primary outcome) and variations in StO2 (secondary outcome) during an ischemia-reperfusion test performed using a vascular occlusion test, comparing the hands of limbs unilaterally affected by CRPS type I with the unaffected contralateral hands. We also determined whether the variations in StO2 were related to a modification in the percentage of subjective pain improvement and in the visual analog scale score. RESULTS: The baseline StO2 of the affected hands was significantly higher than that of the unaffected hands (mean 4.7%; 95% confidence interval: 1.41, 6.7; p = 0.005). Variations in StO2 during the ischemia-reperfusion test revealed no differences between affected and unaffected hands. No significant correlations were detected between baseline StO2 values or variations in StO2 during the vascular occlusion test and the pain measurements. CONCLUSIONS: Baseline StO2 evaluated by NIRS was greater in the affected hands of patients with CRPS type I treated with SCS than in the unaffected, contralateral hands.

Complex Regional Pain Syndrome Management: An Evaluation of the Risks and Benefits of Spinal Cord Stimulator Use in Pregnancy.

OBJECTIVE: We present a case of a young woman diagnosed with complex regional pain syndrome (CRPS) who underwent spinal cord stimulator (SCS) implantation. She had 2 successful pregnancies following implantation. DESIGN: We evaluated the electronic medical records of the patient following SCS implantation and while pregnant with her second and third children. A phone interview was conducted after her third pregnancy to discuss her experience with SCS use during and after pregnancy. SETTING: Physical medicine and rehabilitation pain management clinic and obstetrician clinic, affiliated with the Medical College of Wisconsin in Milwaukee, Wisconsin. SUBJECT: A 26-year-old woman with history of CRPS type I. RESULTS: This 26-year-old woman was diagnosed with CRPS type I after left knee surgery. All conservative treatments had failed prior to her undergoing SCS implantation after the birth of her first child. SCS implantation brought near complete resolution of her symptoms. When she became pregnant with her second child, she turned off her SCS. Her CRPS symptoms intensified, but she had a normal pregnancy. She turned the SCS back on postpartum and elected to continue its use throughout her third pregnancy. She had a normal pregnancy, and her CRPS symptoms were well controlled. The patient and her children are currently healthy. Her SCS remains functional and effective. CONCLUSION: Both an SCS and many medications used for pain management in CRPS could cause harm to both mother and fetus in pregnancy. Further research must be done to determine the safety and efficacy of SCS use in pregnancy.

Dorsal Root Ganglion Stimulation Is Paresthesia-Independent: A Retrospective Study.

INTRODUCTION: Neuromodulation is an important tool for achieving pain relief in otherwise-intractable neuropathic pain conditions. Dorsal root ganglion (DRG) stimulation, in which primary sensory neurons are stimulated prior to their entry into the spinal canal, provides treatment with high levels of dermatomal specificity and can provide advantages compared to conventional spinal cord stimulation. Although DRG stimulation can produce perceptible paresthesias, many patients operate their systems at subthreshold amplitudes that do not elicit this sensation. Pain relief both with and without paresthesia was investigated in this retrospective analysis. MATERIALS AND METHODS: A retrospective review of all qualifying permanent DRG stimulation systems at a single center over more than a three-year period was completed. Pain (0-10 numeric rating scale) was assessed at baseline, at the end of the trial, and after three, six, and twelve months of treatment. Patients were categorized based on their usage of the stimulator at amplitudes that either did or did not produce paresthesias. RESULTS: Of the 39 patients, 34 (87%) reported having no-paresthesias at any of the follow-up visits. Average pain relief was 73.9% after the trial period and 63.1% after 12 months of treatment. The responder rate (50% or better pain relief) after three months of treatment was more than 80%. Exploratory subgroup analyses showed that similar degrees of pain relief were achieved in numerous body regions and with various pain etiologies. The five patients who reported paresthesias during treatment had pain relief similar to those of the group that did not experience paresthesias. DISCUSSION: Clinically significant and sustained pain relief over more than a period of 12 months was achieved with DRG stimulation programmed at amplitudes below the perceptual level. Thus, the reported analgesia was paresthesia-independent. That good clinical outcomes were observed independent of the generation of paresthesia in DRG stimulation suggests several mechanisms of action, including the inhibition of supraspinal regions involved in somatic paresthesia sensation. The retrospective results presented here posit that future prospective study of DRG stimulation delivered at below the threshold of perceptible paresthesias is warranted.

Comparison of Paresthesia Coverage of Patient's Pain: Dorsal Root Ganglion vs. Spinal Cord Stimulation. An ACCURATE Study Sub-Analysis.

OBJECTIVES: This was a sub-analysis of the ACCURATE clinical trial that evaluated the accuracy and necessity of targeting paresthesia coverage of painful areas with dorsal root ganglion (DRG) stimulation vs. tonic spinal cord stimulation (SCS). MATERIALS AND METHODS: On diagrams of the torso and lower limbs, subjects marked where they felt pain at baseline and paresthesias at three months postimplant. Seventy-five subjects (41 DRG and 34 SCS) with diagrams of sufficient quality were scanned, digitized, and included in this analysis. Subject completed diagrams were digitized and superimposed with a grid of 1398 squares. Quantification of the percentage of bodily areas affected by pain and stimulation induced paresthesias was performed. RESULTS: The percent of painful areas covered by paresthesia was significantly lower for DRG subjects than for SCS subjects (13% vs. 28% of the painful regions, p < 0.05), possibly because significantly more DRG subjects felt no paresthesia during stimulation when compared to SCS subjects (13/41 DRG vs. 3/34 SCS) (p < 0.05). The amount of paresthesia produced outside the painful areas (unrequired paresthesia) was significantly lower in DRG subjects than that of SCS subjects. On average, the percent of unrequired paresthesia was only 20% of the subjects' total painful body surface area in the DRG group compared to 210% in the SCS group (p < 0.01). CONCLUSIONS: The results of this ACCURATE study sub-analysis show that DRG stimulation produces paresthesias, on average, that are less frequent, less intense, with a smaller footprint on the body and less dependent on positional changes.

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.

Pain Exposure Physical Therapy versus conventional treatment in complex regional pain syndrome type 1-a cost-effectiveness analysis alongside a randomized controlled trial.

OBJECTIVE: To analyze cost-effectiveness of Pain Exposure Physical Therapy compared to conventional treatment alongside a randomized controlled trial (NCT00817128) in patients with complex regional pain syndrome type 1, where no clinical difference was shown between the two groups in an intention-to-treat analysis. DESIGN: Randomized controlled trial with 9 months follow-up. SETTING: Patients were recruited from hospitals and general practitioners in the region around a university hospital. SUBJECTS: A total of 56 patients, 45 (80.4%) female, were randomized. About 4 patients in the intervention and 11 patients in the conventional group switched groups. The mean (SD) age was 44.3 (16.6) years, and in 37 (66.1%) patients, the upper extremity was affected. INTERVENTIONS: Patients received either Pain Exposure Physical Therapy (maximum of five sessions), or conventional treatment conforming with the Dutch multidisciplinary guideline. MAIN MEASURES: For the economic evaluation difference between the groups in health-related quality of life (quality-adjusted life years (QALYs)), and the clinical outcomes Impairment level Sum Score-Restricted Version and Pain Disability was determined based on the intention-to-treat analysis as well as differences in both healthcare-related costs and travel expenses. Cost-effectiveness planes were constructed using bootstrapping to compare effects and costs. RESULTS: No significant effects were found for QALYs (mean difference = -0.02; 95% confidence interval (CI) -0.10 to 0.04) and clinical outcomes. A cost minimization analysis showed a significant difference in costs between groups. The conventional treatment was 64% more expensive than the Pain Exposure Physical Therapy. CONCLUSION: This economic analysis shows that Pain Exposure Physical Therapy compared to conventional treatment is cost-effective.

Graded motor imagery for women at risk for developing type I CRPS following closed treatment of distal radius fractures: a randomized comparative effectiveness trial protocol.

BACKGROUND: Distal radius fractures (DRF) account for nearly one-fifth of all fractures in older adults, and women experience them 5× as often as men. Most DRF occur with low impact injuries to the wrist with an outstretched hand, and are often managed via closed treatment and cast immobilization. Women sustaining a DRF are at risk for upper limb immobility, sensorimotor changes, edema and type I complex regional pain syndrome (CRPS). Since CRPS onset is likely influenced by alterations in the brain's somatosensory region, a rehabilitation intervention, Graded Motor Imagery (GMI), aims to restore cortical representation, including sensory and motor function, of the affected limb. To date, there are no studies on the use of GMI in reducing risk of or preventing the onset of type I CRPS in women with DRF treated with cast immobilization. Due to a higher likelihood of women with this injury developing type I CRPS, it is important to early intervention is needed. METHODS/DESIGN: This article describes a six-week randomized comparative effectiveness trial, where the outcomes of a modified GMI program (mGMI) + standard of care (SOC) group (n = 33) are compared to a SOC only control group (n = 33). Immediately following cast immobilization, both groups participate in four 1-h clinic-based sessions, and a home program for 10 min three times daily until cast removal. Blinded assessments occur within 1 week of cast immobilization (baseline), at three weeks post cast immbolization, cast removal, and at three months post cast removal. The primary outcomes are patient reported wrist/hand function and symptomology on the Patient Rated Wristand Hand Evaluation, McGill Pain Questionnaire, and Budapest CRPS Criteria. The secondary outcomes are grip strength, active range of motion as per goniometry, circumferential edema measurements, and joint position sense. DISCUSSION: This study will investigate the early effects of mGMI + SOC hand therapy compared to SOC alone. We intend to investigate whether an intervention, specifically mGMI, used to treat preexisiting pain and motor dysfunction might also be used to mitigate these problems prior to their onset. If positive effects are observed, mGMI + SOC may be considered for incorporation into early rehabilitation program. TRIAL REGISTRATION: This trial is registered at ClinicalTrials.gov with identifier NCT02957240 (Approval date: April 20, 2017).

Ultrasound-Guided Intra-articular Injection of the Radio-ulnar and Radio-humeral Joints and Ultrasound-Guided Dry Needling of the Affected Limb Muscles to Relieve Fixed Pronation Deformity and Myofascial Issues around the Shoulder, in a Case of Complex Regional Pain Syndrome Type 1.

BACKGROUND: Complex regional pain syndrome (CRPS) occurs due to different pathophysiological mechanisms. Presently there is no description of definitive treatment that can resolve the especially recalcitrant motor issues of disability in CRPS type 1 (CRPS-1). CASE REPORT: We have herein described the successful management of motor disability with a multimodal approach in a patient with CRPS-1 that occurred as a result of a fracture sustained in the lower end of the radius. Sensory/sudomotor/vasomotor symptoms were relieved completely by medications and stellate ganglion block in 2 weeks. Ultrasound-guided dry needling secured near-complete improvement of shoulder and hand movements in 45 days. Ultrasound guided intra-articular (radio-ulnar and radio-humeral joint) injections with steroid reduced residual pain and improved forearm movements by 50% initially. The patient continued to receive regular sessions of dry needling, physiotherapy, and cognitive behavioral therapy. By the end of 1 year, the functions of the limb improved remarkably, as did the functional outcome scores. CONCLUSION: In this patient with CRPS-1, intra-articular injections with steroid reduced nociception in the affected local structures and sensitization in the nervous system; dry needling resolved the myofascial issues; sustained physiotherapy maintained the motor recovery; and behavioral therapy techniques addressed the cognitive and life stress issues. It was concluded that the presenting symptoms in this case were a consequence of interactions between humoral, nervous, and myofascial systems.

A Case of Spinal Cord Stimulator Recharging Interruption in Wound Healing.

OBJECTIVES: To illustrate the obstacles and problems with electrical fields (EFs) in treatment and management of skin wounds. Unlike the literature that gives evidence for EF promoting wound healing, there is relatively little research to illustrate the interference of wound healing with EFs. MATERIALS AND METHODS: This is a case report of a patient who underwent spinal cord stimulator implantation, and presented with delayed wound healing postoperatively. Postoperative workup for infection was negative. Spinal cord stimulator was programmed to use higher frequencies than traditional settings, which required recharging the pulse generator daily. There was spontaneous improvement of the clinical presentation resulting in adequate wound healing after changing the programming to less frequent recharging requirements. RESULTS: In our case, despite the presence of clinical signs similar to a surgical site infection, the wound healing was most likely interrupted and delayed secondary to the electric field generated due to the frequent recharges of the pulse generator. CONCLUSIONS: It is possible that EF can also negatively impact healing of a wound, and thus should be a consideration to clinicians when a delay in proper wound healing is encountered postoperatively. Therefore, in the postoperative period, when the wound healing is most active, we recommend avoiding programs that require frequent pulse generator recharges.

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.

Successful treatment of intractable complex regional pain syndrome type I of the knee with dorsal root ganglion stimulation: a case report.

OBJECTIVES: To report on the efficacy of dorsal root ganglion stimulation in a patient with complex regional pain syndrome (CRPS) type I of the knee. MATERIALS AND METHODS: A 48-year-old woman with CRPS type I of the right knee, diagnosed according to the Budapest criteria set, received DRG stimulation for intractable CRPS type I of the knee. RESULTS: After a successful trial period with three DRG stimulation leads on spinal levels L2, L3, and L4 (covering 90% of the painful area of her knee), a definitive pulse generator was implanted. Three months after implantation, the entire painful area was covered, and the patient reported a numeric rating scale score of 1-2. CONCLUSION: Placement of three DRG stimulation leads at levels L2, L3, and L4 in a patient with intractable CRPS type I of the knee resulted in major pain relief. We recommend further investigation of the effect of DRG stimulation on pain due to CRPS of the knee.

Restoration of altered somatosensory cortical representation with spinal cord stimulation therapy in a patient with complex regional pain syndrome: a magnetoencephalography case study.

OBJECTIVES: Development of effective chronic pain treatment strategies has been hampered by the lack of an objective pain biomarker. Magnetoencephalography (MEG) has demonstrated cortical disorganization corresponding to the affected limb of complex regional pain syndrome (CRPS) patients and spinal cord stimulation (SCS) can acutely treat CRPS in a reversible and adjustable fashion. In order to better define a potential MEG-sensitive biomarker for chronic pain, our goal was to study the effects of therapeutic SCS on cortical disorganization in patients with unilateral limb CRPS. METHODS: Two patients treated with either thoracic or cervical SCS with leg or arm CRPS were studied with MEG. Baseline and tactile-evoked responses were recorded with and without effective SCS therapy. RESULTS: All MEG recordings were obtained with minimal interference. In the patient with arm CRPS, with the stimulator off, first and fifth digit primary somatosensory (SI) cortical representations (D1/D5) were significantly disorganized and spatially inverted as compared with the opposite unaffected limb. Effective SCS therapy was then able to acutely normalize or restore hand cortical organization in the affected CRPS limb. This restoration of cortical organization was partially maintained with lingering pain relief when the stimulator was subsequently turned off. CONCLUSIONS: This is the first report of a MEG study showing D1/D5 cortical disorganization and its apparent reversal or restoration with cervical SCS therapy. Ours also is the first report of an apparent acute reversible interchange in the cortical representations of D1 and D5. Our limited data demonstrate that disorganization of SI cortex might be a neurophysiologic marker of chronic pain as shown with instantaneous normalization of SI disorganization or restoration of SI organization with therapeutic SCS. As a clinically proven tool for functional mapping, MEG might be shown to provide an objective measure of chronic pain. More data are required to further investigate this possibility.

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.

Mirror visual feedback as therapeutic modality in unilateral upper extremity complex regional pain syndrome type I: randomized controlled trial.

BACKGROUND: There is growing evidence for the effectiveness of mirror therapy (MT) on pain reduction in patients with type I complex regional pain syndrome (CRPS I). AIM: To evaluate the efficacy of MT on pain reduction and hand function in subjects with unilateral upper extremity CRPS I. DESIGN: Randomized controlled trial with control group cross-over (half cross-over design). SETTING: Subjects with CRPS I were outpatients of a university hospital and cooperating centers. All patients carried out the daily exercise at home. POPULATION: Subjects with unilateral upper extremity CRPS I meeting the Budapest diagnostic criteria. METHODS: Subjects were randomly divided into two groups. Group A (N.=13) carried out a ten-minute MT exercise daily, for a total duration of six weeks. Group B (N.=14) acted as a control group for six weeks followed by six weeks of MT with the same characteristics as Group A. Upper extremity active range of motion, strength, dexterity, limb volume, affected-to-unaffected hand temperature difference, and health-related quality of life were evaluated before and after each period. Daily records on the visual analogue scale were used for pain evaluation. Effectiveness was calculated using mixed-effects modelling for between-group comparisons and within-group variability, and identification of significant predictors. RESULTS: Twenty-three females and four males with an average age of 56.1±9.6 years completed the study. Except for the affected-to-unaffected hand temperature difference, both groups consistently demonstrated significant or near-significant improvements in measured parameters after MT period. The improvements were evident upon an intergroup comparison of Group A and the control period of Group B as well as longitudinally within Group B. No significant improvement was found during the control period. CONCLUSIONS: Principles focused on mirror visual feedback to the central nervous system can sustain promising therapeutic potential as part of the treatment for pain reduction and hand function in CRPS I patients. CLINICAL REHABILITATION IMPACT: MT can be considered as part of the therapeutic regimen employed for the treatment of CRPS I.

CT-guided stellate ganglion blockade vs. radiofrequency neurolysis in the management of refractory type I complex regional pain syndrome of the upper limb.

OBJECTIVE: To describe and evaluate the feasibility and efficacy of CT-guided radiofrequency neurolysis (RFN) vs. local blockade of the stellate ganglion in the management of chronic refractory type I complex regional pain syndrome (CRPS) of the upper limb. METHODS: Sixty-seven patients were included in this retrospective study between 2000 and 2011. All suffered from chronic upper limb type I CRPS refractory to conventional pain therapies. Thirty-three patients underwent stellate ganglion blockade and 34 benefited from radiofrequency neurolysis of the stellate ganglion. CT guidance was used in both groups. The procedure was considered effective when pain relief was ≥50 %, lasting for at least 2 years. RESULTS: Thirty-nine women (58.2 %) and 28 men (41.8 %) with a mean age of 49.5 years were included in the study. Univariate analysis performed on the blockade and RFN groups showed a significantly (P < 0.0001) higher success rate in the RFN group (67.6 %, 23/34) compared with the blockade group (21.2 %, 7/33) with an odds ratio of 7.76. CONCLUSION: CT-guided radiofrequency neurolysis of the stellate ganglion is a safe and successful treatment of chronic refractory type I CRPS of the upper limb. It appears to be more effective than stellate ganglion blockade. KEY POINTS: • Complex regional pain syndrome is painful, disabling and often refractory to treatment. • Sixty-seven percent of patients had lasting pain relief (2 years) after radiofrequency neurolysis. • Retrospective study showed a significantly higher success rate for radiofrequency neurolysis. • CT guidance is mandatory for a successful and safe procedure.