Impairment level SumScore for lower extremity Complex Regional Pain Syndrome type I

Objectives : To construct a single indicator on impairment level for lower extremity Complex Regional Pain syndrome type I (CRPS I).

Design : The Impairment level SumScore (ISS) for upper extremity CRPS I was adapted to be used for lower extremity evaluation. Medline literature search and research findings were used to adapt the upper extremity version of the ISS, with emphasis on reliability, responsiveness and validity of measurement instruments. Where needed, additional patient data was gathered to evaluate these aspects for different measurement instruments.

Setting : An outpatient clinic of a university hospital in the Netherlands.

Participants : Two groups consisting of 17 and 26 healthy volunteers, and two groups of respectively 40 and 18 lower extremity CRPS I patients according to Veldman's criteria.

Main outcome measures : VAS and McGill pain scores, water displacement volumeter values, and physicians' and patients' assessment of CRPS I severity.

Results : A combination of measurements, incorporating pain (VAS and McGill), temperature (infrared thermometer), volume (water displacement volumeter) and active range of motion (universal goniometer), was converted in a single score ranging from 5 to 50. The reliability, as well as the responsiveness was adequate.

Conclusions : The lower extremity ISS permits evaluation of the most prominent symptoms in CRPS I, and can be used to monitor changes in CRPS I.     

Abnormal thalamocortical activity in patients with Complex Regional Pain Syndrome (CRPS) Type I

Complex Regional Pain Syndrome (CRPS) is a neuropathic disease that presents a continuing challenge in terms of pathophysiology, diagnosis, and treatment. Recent studies of neuropathic pain, in both animals and patients, have established a direct relationship between abnormal thalamic rhythmicity related to Thalamo-cortical Dysrhythmia (TCD) and the occurrence of central pain. Here, this relationship has been examined using magneto-encephalographic (MEG) imaging in CRPS Type I, characterized by the absence of nerve lesions. The study addresses spontaneous MEG activity from 13 awake, adult patients (2 men, 11 women; age 15–62), with CRPS Type I of one extremity (duration range: 3 months to 10 years) and from 13 control subjects. All CRPS I patients demonstrated peaks in power spectrum in the delta (<4 Hz) and/or theta (4–9 Hz) frequency ranges resulting in a characteristically increased spectral power in those ranges when compared to control subjects. The localization of such abnormal activity, implemented using independent component analysis (ICA) of the sensor data, showed delta and/or theta range activity localized to the somatosensory cortex corresponding to the pain localization, and to orbitofrontal–temporal cortices related to the affective pain perception. Indeed, CRPS Type I patients presented abnormal brain activity typical of TCD, which has both diagnostic value indicating a central origin for this ailment and a potential treatment interest involving pharmacological and electrical stimulation therapies.     

Complex Regional Pain Syndrome (CRPS): Survey of Current Practices

Background and Objectives: There are numerous treatments for complex regional pain syndrome (CRPS). These treatments are varied in scope and include pain management therapies, psychological therapies, and physiotherapy. Treatment guidelines have been published in the past, but little information exists as to how clinicians utilize these guidelines. Moreover, there has been a paradigm shift from the older “reflex sympathetic dystrophy” (RSD) nomenclature, with largely sympathetic block driven diagnosis and therapy to more recent trends towards more inclusive “CRPS” diagnostic criteria and multidisciplinary treatment. There remains controversy regarding the selection of various techniques, and the timing of advancement through the treatment algorithm to the more aggressive, interventional techniques. We set out to determine current CRPS treatment practices of interventional pain specialists. Methods: The authors developed a 36‐item, 15–20‐minute questionnaire. This questionnaire was sent to 453 interventional pain specialists. Results: One‐hundred‐five surveys were returned, with 100 being complete. Eighty‐three percent of our respondents were practicing anesthesiology pain specialists who on average treat 14.9 (SD = 16.8) CRPS patients per month. Conclusions: Our survey results revealed the use of a treatment algorithm for CRPS that consists of treatment using medical therapies (pharmacologic, blocks, catheters, and implantable devices), psychological therapies, and physiotherapy in a coordinated fashion. The trend among our survey respondents is to utilize increasingly interventional techniques after a failed 2‐ to 4‐week trial of any one particular therapy.     

Enhanced pain and autonomic responses to ambiguous visual stimuli in chronic Complex Regional Pain Syndrome (CRPS) type I

Cortical reorganisation of sensory, motor and autonomic systems can lead to dysfunctional central integrative control. This may contribute to signs and symptoms of Complex Regional Pain Syndrome (CRPS), including pain. It has been hypothesised that central neuroplastic changes may cause afferent sensory feedback conflicts and produce pain. We investigated autonomic responses produced by ambiguous visual stimuli (AVS) in CRPS, and their relationship to pain. Thirty CRPS patients with upper limb involvement and 30 age and sex matched healthy controls had sympathetic autonomic function assessed using laser Doppler flowmetry of the finger pulp at baseline and while viewing a control figure or AVS. Compared to controls, there were diminished vasoconstrictor responses and a significant difference in the ratio of response between affected and unaffected limbs (symmetry ratio) to a deep breath and viewing AVS. While viewing visual stimuli, 33.5% of patients had asymmetric vasomotor responses and all healthy controls had a homologous symmetric pattern of response. Nineteen (61%) CRPS patients had enhanced pain within seconds of viewing the AVS. All the asymmetric vasomotor responses were in this group, and were not predictable from baseline autonomic function. Ten patients had accompanying dystonic reactions in their affected limb: 50% were in the asymmetric sub‐group. In conclusion, there is a group of CRPS patients that demonstrate abnormal pain networks interacting with central somatomotor and autonomic integrational pathways.     

Repetitive Transcranial Magnetic Stimulation Is Efficacious as an Add-On to Pharmacological Therapy in Complex Regional Pain Syndrome (CRPS) Type I

Single-session repetitive transcranial magnetic stimulation (rTMS) of the motor cortex (M1) is effective in the treatment of chronic pain patients, but the analgesic effect of repeated sessions is still unknown. We evaluated the effects of rTMS in patients with refractory pain due to complex regional pain syndrome (CRPS) type I. Twenty-three patients presenting CRPS type I of 1 upper limb were treated with the best medical treatment (analgesics and adjuvant medications, physical therapy) plus 10 daily sessions of either real (r-) or sham (s-) 10Hz rTMS to the motor cortex (M1). Patients were assessed daily and after 1 week and 3 months after the last session using the Visual Analogical Scale (VAS), the McGill Pain Questionnaire (MPQ), the Health Survey-36 (SF-36), and the Hamilton Depression (HDRS). During treatment there was a significant reduction in the VAS scores favoring the r-rTMS group, mean reduction of 4.65 cm (50.9%) against 2.18 cm (24.7%) in the s-rTMS group. The highest reduction occurred at the tenth session and correlated to improvement in the affective and emotional subscores of the MPQ and SF-36. Real rTMS to the M1 produced analgesic effects and positive changes in affective aspects of pain in CRPS patients during the period of stimulation.     

Resilience in patients with amputation because of Complex Regional Pain Syndrome type I

Abstract

Purpose: Although controversial, an amputation for longstanding and therapy-resistant Complex Regional Pain Syndrome Type I (CRPS-I) may improve quality of life and pain intensity. Resilience, the way people deal with adversity in a positive way may be related to these positive outcomes. This study focused on the relationship between resilience and post-amputation outcomes, i.e. quality of life, pain and recurrence of CRPS-I and psychological distress. Method: Twenty-six patients with an amputation related to CRPS-I filled in the Connor-Davidson Resilience Scale (CD-RISC), World Health Organisation -- Quality of life Assessment (WHOQOL-Bref) and the Symptom Checklist-90 Revised (SCL-90-R). An interview was conducted and a physical examination performed. Results were compared with reference groups from literature and a control group from the outpatient rehabilitation clinic at our medical center. Results: Resilience correlated significantly with all domains of the WHOQOL-Bref (ρ ranged from 0.41 to 0.72) and negatively with all domains of the SCL-90-R (ρ ranged from ?0.39 to ?0.68). Patients with an amputation because of CRPS-I have higher scores on resilience and quality of life than the control group. Resilience was lower in patients who reported CRPS-I symptoms compared to those who did not. Conclusions: The results confirmed our hypothesis that patients with an amputation because of CRPS-I who have a higher resilience also have a higher quality of life and experience lower psychological distress. The prognostic value of resilience in this patient group requires further research.

• Implications for Rehabilitation

• Until characteristics of patients with positive quality of life outcome have been further unraveled, amputation for CRPS-I should only be performed in expertise centers.

• Resilience, the process of adapting well in the face of adversity, should be further explored in Rehabilitation Medicine research in general.

• Measurement of resilience should be a standard procedure when patients with CRPS-I request an amputation.

• Improving resilience of patients in in- and outpatient rehabilitation clinics might be an additional treatment in rehabilitation care.

     

复杂性区域疼痛综合征发病的研究进展

复杂性区域疼痛综合征是一临床发生、发展过程复杂的慢性神经病理性疼痛综合征,本文就其流行病学、发病影响因素、可能的发病机制以及中枢和外周病理生理学变化的最新进展做一综述.     

The efficiency of electromagnetic field treatment in Complex Regional Pain Syndrome Type I

Introduction:?Complex Regional Pain Syndrome Type I is a pathological condition that occurs without evident nerve injury and follows a course characterized by severe pain.

Purpose:?The aim of this study is to assess whether or not electromagnetic field treatment administered with calcitonin and exercise has positive effects on clinical improvement, scintigraphic assessment and bone markers compared to calcitonin and exercise administration.

Method:?In this randomized double-blind, placebo-controlled study, 40 patients with Complex Regional Pain Syndrome Type I, that developed after a Colles fracture were included in the assessments and were administered calcitonin and exercise treatment for 6 weeks. In addition to this treatment, half the patients received electromagnetic field treatment, and the other half received placebo treatment. The patients were evaluated at the beginning and end of treatment with clinical parameters, scintigraphic assessment and biochemical markers.

Results:?Although we found some significant improvements in our evaluation criteria, we could not find a significant statistical difference between groups.

Conclusions:?The absence of a significant difference between the two groups in the assessment parameters has been interpreted as evidence that electromagnetic field treatment does not provide additional benefit to calcitonin and exercise treatment.     

Oral Ketamine for the Treatment of Type I Complex Regional Pain Syndrome

Abstract:   Ketamine has been shown to be effective in the treatment of neuropathic pain. We present a case of severe complex regional pain syndrome type 1 that was treated with oral ketamine. The response and tolerability of this preparation suggest that further study is warranted.     

The efficiency of electromagnetic field treatment in Complex Regional Pain Syndrome Type I

Introduction: Complex Regional Pain Syndrome Type I is a pathological condition that occurs without evident nerve injury and follows a course characterized by severe pain.

Purpose: The aim of this study is to assess whether or not electromagnetic field treatment administered with calcitonin and exercise has positive effects on clinical improvement, scintigraphic assessment and bone markers compared to calcitonin and exercise administration.

Method: In this randomized double-blind, placebo-controlled study, 40 patients with Complex Regional Pain Syndrome Type I, that developed after a Colles fracture were included in the assessments and were administered calcitonin and exercise treatment for 6 weeks. In addition to this treatment, half the patients received electromagnetic field treatment, and the other half received placebo treatment. The patients were evaluated at the beginning and end of treatment with clinical parameters, scintigraphic assessment and biochemical markers.

Results: Although we found some significant improvements in our evaluation criteria, we could not find a significant statistical difference between groups.

Conclusions: The absence of a significant difference between the two groups in the assessment parameters has been interpreted as evidence that electromagnetic field treatment does not provide additional benefit to calcitonin and exercise treatment.     

The Outcome of Complex Regional Pain Syndrome Type 1: A Systematic Review

The purpose of this systematic review was to examine the outcome of complex regional pain syndrome (CRPS) type 1. We searched MEDLINE, Embase, and PsycINFO for relevant studies and included 18 studies, with 3,991 participants, in this review. The following data were extracted: study details, measurement tools used, and rates or severity scores for the symptoms/signs of CRPS at baseline and follow-up, or in groups of patients with different disease durations. A quality assessment revealed significant limitations in the literature, with many studies using different diagnostic criteria. The 3 prospective studies demonstrated that for many patients, symptoms improve markedly within 6 to 13 months of onset. The 12 retrospective studies had highly heterogeneous findings, documenting lasting impairments in many patients. The 3 cross-sectional studies showed that rates of pain and sensory symptoms were highest among those with the longest duration of CRPS. Additionally, most studies showed that motor symptoms (stiffness and weakness) were the most likely to persist whereas sudomotor and vasomotor symptoms were the most likely to improve. Overall, this suggests that some CRPS patients make a good early recovery whereas others develop lasting pain and disability. As yet little is known about the prognostic factors that might differentiate between these groups.PerspectiveWe found evidence that many CRPS patients recover within 6 to 13 months, but a significant number experience some lasting symptoms, and some experience chronic pain and disability. The quality of the evidence was poor. Future research should examine the factors associated with recovery and identify those at risk of poor outcomes.     

A Severe Case of Complex Regional Pain Syndrome I (Reflex Sympathetic Dystrophy) Managed with Spinal Cord Stimulation

Complex regional pain syndrome is a condition that usually affects the upper or lower extremities. The cause is not clearly understood. We report a case of a severe form of a rapidly progressive complex regional pain syndrome type I developing after a right shoulder injury managed with spinal cord stimulation (SCS). After failed conservative treatments, a rechargeable SCS system was implanted in the cervical spine. Allodynia and dystonia improved but the patient subsequently developed similar symptoms in lower right extremity followed by her lower left extremity. The patient became wheelchair bound. A second rechargeable SCS with a paddle electrode was implanted for the lower extremity coverage. The patient's allodynia and skin lesions improved significantly. However, over time, her initial symptoms reappeared which included skin breakdown. Due to the need for frequent recharging, the system was removed. During explantation of the surgical paddle lead, it was noted by the neurosurgeon that the contacts of the paddle lead were detached from the lead. After successful implantation of another SCS system, the patient was able to reduce her medications and is now able to ambulate with the use of a left elbow crutch.     

Brush‐evoked allodynia predicts outcome of spinal cord stimulation in Complex Regional Pain Syndrome type 1

Background: Spinal cord stimulation (SCS) has proven to be an effective however an invasive and relatively expensive treatment of chronic Complex Regional Pain Syndrome type 1(CRPS‐1). Furthermore, in one third of CRPS‐1 patients, SCS treatment fails to give significant pain relief and 32–38% of treated patients experience complications. The aim of the current study was to develop effective prognostic factors for prediction of successful outcome of SCS. Methods and results: The study population consisted of 36 chronic CRPS patients enrolled in a randomized controlled trial of SCS efficacy. We analyzed various prognostic factors in the group of patients treated with SCS and compared baseline values of possible predictors of outcome in the successfully treated and the not successfully treated group. Success was defined as Patient Global Perceived Impression of Change score of at least “much improved” and pain reduction of at least 2.5 on a visual‐analogue scale (VAS score 0–10). Univariate analyses showed that patient age, duration of the disease, localization of the disease, intensity of the pain, and the presence of mechanical hypoesthesia did not predict SCS success. The mean and maximum value of brush‐evoked allodynia proved to be statistically significant predictors of outcome. Using Receiver‐Operating Characteristic (ROC) curve analyses of maximum allodynia values, the diagnostic sensitivity for successful SCS was 0.75 and the specificity 0.81. Conclusion: Brush‐evoked allodynia may be a significant negative prognostic factor of SCS treatment outcome after 1 year in chronic CRPS‐1.     

Impaired spatial body representation in complex regional pain syndrome type 1 (CRPS I)

Recently, a shift of the visual subjective body midline (vSM), a correlate of the egocentric reference frame, towards the affected side was reported in patients with complex regional pain syndrome (CRPS). However, the specificity of this finding is as yet unclear. This study compares 24 CRPS patients to 21 patients with upper limb pain of other origin (pain control) and to 24 healthy subjects using a comprehensive test battery, including assessment of the vSM in light and dark, line bisection, hand laterality recognition, neglect-like severity symptoms, and motor impairment (disability of the arm, shoulder, and hand). Statistics: 1-way analysis of variance, t-tests, significance level: 0.05. In the dark, CRPS patients displayed a significantly larger leftward spatial bias when estimating their vSM, compared to pain controls and healthy subjects, and also reported lower motor function than pain controls. For right-affected CRPS patients only, the deviation of the vSM correlated significantly with the severity of distorted body perception. Results confirm previous findings of impaired visuospatial perception in CRPS patients, which might be the result of the involvement of supraspinal mechanisms in this pain syndrome. These mechanisms might accentuate the leftward bias that results from a right-hemispheric dominance in visuospatial processing and is known as pseudoneglect. Pseudoneglect reveals itself in the tendency to perceive the midpoint of horizontal lines or the subjective body midline left of the centre. It was observable in all 3 groups, but most pronounced in CRPS patients, which might be due to the cortical reorganisation processes associated with this syndrome.     

Complex Regional Pain Syndrome I: Management through the Use of Vertebral and Sympathetic Trunk Mobilization

Abstract

The purpose of this study was to describe the clinical differential diagnostic process and effective management of an individual presenting with lower-extremity complex regional pain syndrome I (CRPS I). A 50-year-old female 8-weeks status post ORIF right tibia/fibula presented with a warm, red, edematous, hyperhidrotic right lower extremity. She also exhibited hyperalgesia, allodynia, and a positive slump test on the right. The patient satisfied clinical diagnostic criteria for a diagnosis of CRPS I. The subject was treated for 10 sessions over a 3-month period using progressive desensitization, weight-bearing activities, thoracolumbar mobilizations, and a neural mobilization technique referred to as slump long sitting with sympathetic emphasis (SLSSE). An analysis of outcome measures at the time of discharge and at a one-year follow-up demonstrated a significant improvement in both pain and function. Effective management was achieved by addressing both the patient's proximal and distal impairments including thoracolumbar segmental lesions and positive neurodynamic tests. It is speculated that the influence of neural mobilizations to the ipsilateral sympathetic ganglia directly affected the pathophysiology associated with autonomic dysregulation and pain in this subject. This case report provides initial evidence that the SLSSE may be an effective neural mobilization technique in reducing the magnitude of symptoms and improving function in patients with CRPS.     

Treatment of Complex Regional Pain Syndrome Type I With Oral Phenoxybenzamine: Rationale and Case Reports

▪ Abstract:   The nonselective α-adrenergic antagonist, phenoxybenzamine, has been used in the treatment of neuropathic pain syndromes, specifically, complex regional pain syndrome (CRPS) types I and II. This agent has also previously been used in intravenous regional peripheral blocks for treatment of CRPS I; however, an intravenous preparation of phenoxybenzamine is not currently available in the U.S.A. In this case series, systemic administration was more appropriate for three of the four patients, as their syndromes had spread beyond the initial area of surgery or trauma. We report an apparent clinical benefit in three of the four patients following oral administration. We postulate that this may be due to the noncompetitive (irreversible) blockade of α₁- and α₂-adrenergic receptors. We further hypothesize that this blockade could reduce stimulation of an increased population of adrenergic receptors in hyperalgesic skin, blunt the stimulation by norepinephrine of α₂-adrenergic receptors on macrophages, and ultimately reduce the release of proinflammatory cytokines from cellular elements. ▪     

Muscle Hyperalgesia Correlates With Motor Function in Complex Regional Pain Syndrome Type 1

At present it is unclear if disturbed sensory processing plays a role in the development of the commonly observed motor impairments in patients with complex regional pain syndrome (CRPS). This study aims to investigate the relation between sensory and motor functioning in CRPS patients with and without dystonia. Patients with CRPS of the arm and controls underwent comprehensive quantitative sensory testing and kinematic analysis of repetitive finger movements. Both CRPS groups showed thermal hypoesthesia to cold and warm stimuli and hyperalgesia to cold stimuli. A decreased pressure pain threshold reflecting muscle hyperalgesia emerged as the most prominent sensory abnormality in both patient groups and was most pronounced in CRPS patients with dystonia. Moreover, the decreased pressure pain threshold was the only nociceptive parameter that related to measures of motor function in both patients and controls. CRPS patients with dystonia had an increased 2-point discrimination as compared to controls and CRPS patients without dystonia. This finding was also reported in other types of dystonia and has been associated to cortical reorganization in response to impaired motor function. We hypothesize that increased sensitivity of the circuitry mediating muscle nociception may play a crucial role in impaired motor control in CRPS.PerspectiveThis is the first study linking a sensory dysfunction, ie, muscle hyperalgesia, to motor impairment in CRPS. Circuitries mediating muscle nociception may therefore play an important role in impaired motor control in CRPS.     

Activation of Cutaneous Immune Responses in Complex Regional Pain Syndrome

The pathogenesis of complex regional pain syndrome (CRPS) is unresolved, but tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) are elevated in experimental skin blister fluid from CRPS-affected limbs, as is tryptase, a marker for mast cells. In the rat fracture model of CRPS, exaggerated sensory and sympathetic neural signaling stimulate keratinocyte and mast cell proliferation, causing the local production of high levels of inflammatory cytokines leading to pain behavior. The current investigation used CRPS patient skin biopsies to determine whether keratinocyte and mast cell proliferation occur in CRPS skin and to identify the cellular source of the up-regulated TNF-α, IL-6, and tryptase observed in CRPS experimental skin blister fluid. Skin biopsies were collected from the affected skin and the contralateral mirror site in 55 CRPS patients and the biopsy sections were immunostained for keratinocyte, cell proliferation, mast cell markers, TNF-α, and IL-6. In early CRPS, keratinocytes were activated in the affected skin, resulting in proliferation, epidermal thickening, and up-regulated TNF-α and IL-6 expression. In chronic CRPS, there was reduced keratinocyte proliferation, leading to epidermal thinning in the affected skin. Acute CRPS patients also had increased mast cell accumulation in the affected skin, but there was no increase in mast cell numbers in chronic CRPS.PerspectiveThe results of this study support the hypotheses that CRPS involves activation of the innate immune system, with keratinocyte and mast cell activation and proliferation, inflammatory mediator release, and pain.