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Neuropathic pain in people with spinal cord injury is thought to be due to altered central neuronal activity. A novel therapeutic intervention using virtual reality (VR) head-mounted devices was investigated in this study for pain relief. Given the potential links to neuronal activity, the aim of the current study was to determine whether use of VR was associated with corresponding changes in electroencephalography (EEG) patterns linked to the presence of neuropathic pain. Using a within-subject, randomised cross-over pilot trial, we compared EEG activity for three conditions: no task eyes open state, 2D screen task and 3D VR task. We found an increase in delta activity in frontal regions for 3D VR with a decrease in theta activity. There was also a consistent decrease in relative alpha band (8-12 Hz) and an increase in low gamma (30-45 Hz) power during 2D screen and 3D VR corresponding, with reduced self-reported pain. Using the nonlinear and non-oscillatory method of extracting fractal dimensions, we found increases in brain complexity during 2D screen and 3D VR. We successfully classified the 3D VR condition from 2D screen and eyes opened no task conditions with an overall accuracy of 80.3%. The findings in this study have implications for using VR applications as a therapeutic intervention for neuropathic pain in people with spinal cord injury.

Objectives: The objective of this study was to develop the International Spinal Cord Injury Pain Extended Data Set (ISCIPEDS) with the purpose of guiding the assessment and treatment of pain after spinal cord injury (SCI)., Setting: International., Methods: The ISCIPEDS was reviewed by members of the International SCI Data Sets Committee, the International Spinal Cord Society Executive and Scientific Committees, American Spinal Injury Association and American Pain Society Boards, and the Neuropathic Pain Special Interest Group of the International Association for the Study of Pain, individual reviewers and societies., Results: The working group recommended four assessment domains for the ISCIPEDS: (i) Pain symptoms including variables related to pain type, temporal course, severity, unpleasantness, tolerability of pain and questionnaires assessing pain type and symptom severity; (ii) Sensory signs to detect and quantify sensory abnormalities commonly associated with neuropathic pain, including dynamic mechanical and thermal allodynia, and hyperalgesia; (iii) Treatments (ongoing and past 12 months); and (iv) Psychosocial factors and comorbid conditions., Conclusion: The ISCIPEDS was designed to be used together with the International SCI Pain Basic Data Set and provide a brief yet thorough assessment of domains related to chronic pain in individuals with SCI. The data set includes pain-relevant self-reported assessments, questionnaires and sensory examinations. The recommendations were based on (i) their relevance to individuals with SCI and chronic pain, (ii) the existence of published findings supporting the utility of the selected measures for use in individuals with SCI, and to the greatest extent possible (iii) their availability in the public domain free of charge.

Study Design: Clinical practice guidelines., Objectives: The project objectives were to develop the first Canadian recommendations on a model of care for the management of at- and below-level neuropathic pain in people with spinal cord injury (SCI)., Setting: The guidelines are relevant for inpatient and outpatient SCI rehabilitation settings in Canada., Methods: On the basis of a review of the Accreditation Canada standards, the Steering Committee developed questions to guide the CanPainSCI Working Group when developing the recommendations. The Working Group agreed on recommendations through a consensus process., Results: The Working Group developed five recommendations for the organization of neuropathic pain rehabilitation care in people with SCI., Conclusions: The Working Group recommendations for a model of care for at- and below-level neuropathic pain after SCI should be used to inform clinical practice.

Study Design: Clinical practice guidelines., Objectives: To develop the first Canadian clinical practice guidelines for treatment of neuropathic pain in people with spinal cord injury (SCI)., Setting: The guidelines are relevant for inpatient and outpatient SCI rehabilitation settings in Canada., Methods: The CanPainSCI Working Group reviewed the evidence for different treatment options and achieved consensus. The Working Group then developed clinical considerations for each recommendation. Recommendations for research are also included., Results: Twelve recommendations were developed for the management of neuropathic pain after SCI. The recommendations address both pharmacologic and nonpharmacologic treatment modalities., Conclusions: An expert Working Group developed recommendations for the treatment of neuropathic pain after SCI that should be used to inform practice.

Study Design: Clinical practice guidelines., Objectives: The objective was to develop the first Canadian clinical practice guidelines for the management of neuropathic pain in people with spinal cord injury (SCI)., Setting: The guidelines are relevant for inpatient and outpatient SCI rehabilitation settings in Canada., Methods: The guidelines were developed in accordance with the Appraisal of Guidelines for Research and Evaluation II tool. A Steering Committee and Working Group reviewed the relevant evidence on neuropathic pain management (encompassing screening and diagnosis, treatment and models of care) after SCI. The quality of evidence was scored using Grading of Recommendations Assessment, Development and Evaluation (GRADE). A consensus process was followed to achieve agreement on recommendations and clinical considerations., Results: The Working Group developed 12 recommendations for screening and diagnosis, 12 recommendations for treatment and 5 recommendations for models of care. Important clinical considerations accompany each recommendation., Conclusions: The Working Group recommendations for the management of neuropathic pain after SCI should be used to inform practice.

Study Design: Clinical practice guidelines., Objectives: To develop the first Canadian clinical practice guidelines for screening and diagnosis of neuropathic pain in people with spinal cord injury (SCI)., Setting: The guidelines are relevant for inpatient and outpatient SCI rehabilitation settings in Canada., Methods: The CanPainSCI Working Group reviewed evidence to address clinical questions regarding screening and diagnosis of neuropathic pain after SCI. A consensus process was followed to achieve agreement on recommendations and clinical considerations., Results: Twelve recommendations, based on expert consensus, were developed for the screening and diagnosis of neuropathic pain after SCI. The recommendations address methods for assessment, documentation tools, team member accountability, frequency of screening and considerations for diagnostic investigation. Important clinical considerations accompany each recommendation., Conclusions: The expert Working Group developed recommendations for the screening and diagnosis of neuropathic pain after SCI that should be used to inform practice.

Background: New drug treatments, clinical trials, and standards of quality for assessment of evidence justify an update of evidence-based recommendations for the pharmacological treatment of neuropathic pain. Using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE), we revised the Special Interest Group on Neuropathic Pain (NeuPSIG) recommendations for the pharmacotherapy of neuropathic pain based on the results of a systematic review and meta-analysis., Methods: Between April, 2013, and January, 2014, NeuPSIG of the International Association for the Study of Pain did a systematic review and meta-analysis of randomised, double-blind studies of oral and topical pharmacotherapy for neuropathic pain, including studies published in peer-reviewed journals since January, 1966, and unpublished trials retrieved from ClinicalTrials.gov and websites of pharmaceutical companies. We used number needed to treat (NNT) for 50% pain relief as a primary measure and assessed publication bias; NNT was calculated with the fixed-effects Mantel-Haenszel method., Findings: 229 studies were included in the meta-analysis. Analysis of publication bias suggested a 10% overstatement of treatment effects. Studies published in peer-reviewed journals reported greater effects than did unpublished studies (r(2) 9·3%, p=0·009). Trial outcomes were generally modest: in particular, combined NNTs were 6·4 (95% CI 5·2-8·4) for serotonin-noradrenaline reuptake inhibitors, mainly including duloxetine (nine of 14 studies); 7·7 (6·5-9·4) for pregabalin; 7·2 (5·9-9·21) for gabapentin, including gabapentin extended release and enacarbil; and 10·6 (7·4-19·0) for capsaicin high-concentration patches. NNTs were lower for tricyclic antidepressants, strong opioids, tramadol, and botulinum toxin A, and undetermined for lidocaine patches. Based on GRADE, final quality of evidence was moderate or high for all treatments apart from lidocaine patches; tolerability and safety, and values and preferences were higher for topical drugs; and cost was lower for tricyclic antidepressants and tramadol. These findings permitted a strong recommendation for use and proposal as first-line treatment in neuropathic pain for tricyclic antidepressants, serotonin-noradrenaline reuptake inhibitors, pregabalin, and gabapentin; a weak recommendation for use and proposal as second line for lidocaine patches, capsaicin high-concentration patches, and tramadol; and a weak recommendation for use and proposal as third line for strong opioids and botulinum toxin A. Topical agents and botulinum toxin A are recommended for peripheral neuropathic pain only., Interpretation: Our results support a revision of the NeuPSIG recommendations for the pharmacotherapy of neuropathic pain. Inadequate response to drug treatments constitutes a substantial unmet need in patients with neuropathic pain. Modest efficacy, large placebo responses, heterogeneous diagnostic criteria, and poor phenotypic profiling probably account for moderate trial outcomes and should be taken into account in future studies., Funding: NeuPSIG of the International Association for the Study of Pain., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

There is increasing evidence relating thalamic changes to the generation and/or maintenance of neuropathic pain. We have recently reported that neuropathic orofacial pain is associated with altered thalamic anatomy, biochemistry, and activity, which may result in disturbed thalamocortical oscillatory circuits. Despite this evidence, it is possible that these thalamic changes are not responsible for the presence of pain per se, but result as a consequence of the injury. To clarify this subject, we compared brain activity and biochemistry in 12 people with below-level neuropathic pain after complete thoracic spinal cord injury with 11 people with similar injuries and no neuropathic pain and 21 age- and gender-matched healthy control subjects. Quantitative arterial spinal labelling was used to measure thalamic activity, and magnetic resonance spectroscopy was used to determine changes in neuronal variability quantifying N-acetylaspartate and alterations in inhibitory function quantifying gamma amino butyric acid. This study revealed that the presence of neuropathic pain is associated with significant changes in thalamic biochemistry and neuronal activity. More specifically, the presence of neuropathic pain after spinal cord injury is associated with significant reductions in thalamic N-acetylaspartate, gamma amino butyric acid content, and blood flow in the region of the thalamic reticular nucleus. Spinal cord injury on its own did not account for these changes. These findings support the hypothesis that neuropathic pain is associated with altered thalamic structure and function, which may disturb central processing and play a key role in the experience of neuropathic pain., (Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.)

The most obvious impairments associated with spinal cord injury (SCI) are loss of sensation and motor control. However, many subjects with SCI also develop persistent neuropathic pain below the injury which is often severe, debilitating and refractory to treatment. The underlying mechanisms of persistent neuropathic SCI pain remain poorly understood. Reports in amputees describing phantom limb pain demonstrate a positive correlation between pain intensity and the amount of primary somatosensory cortex (S1) reorganization. Of note, this S1 reorganization has also been shown to reverse with pain reduction. It is unknown whether a similar association between S1 reorganization and pain intensity exists in subjects with SCI. The aim of this investigation was to determine whether the degree of S1 reorganization following SCI correlated with on-going neuropathic pain intensity. In 20 complete SCI subjects (10 with neuropathic pain, 10 without neuropathic pain) and 21 control subjects without SCI, the somatosensory cortex was mapped using functional magnetic resonance imaging during light brushing of the right little finger, thumb and lip. S1 reorganization was demonstrated in SCI subjects with the little finger activation point moving medially towards the S1 region that would normally innervate the legs. The amount of S1 reorganization in subjects with SCI significantly correlated with on-going pain intensity levels. This study provides evidence of a link between the degree of cortical reorganization and the intensity of persistent neuropathic pain following SCI. Strategies aimed at reversing somatosensory cortical reorganization may have therapeutic potential in central neuropathic pain.

Study Design: Brain wave activity in people with paraplegia, with and without neuropathic pain, was compared to brain wave activity in matched able-bodied controls., Objectives: To investigate whether spinal cord injury with neuropathic pain is associated with a slowing of brain wave activity., Setting: Australia., Methods: Electroencephalographic (EEG) data were collected in the eyes open (EO) and eyes closed (EC) states from 16 participants with paraplegia (eight with neuropathic pain and eight without pain) and matched able-bodied controls. Common EEG artefacts were removed using independent component analysis (ICA). Peak frequency in the theta-alpha band and EEG power in the delta, theta, alpha and beta frequency bands were compared between groups., Results: The results show significant slowing of the EEG in people with neuropathic pain, consistent with the presence of thalamocortical dysrhythmia (TCD). Furthermore, people with neuropathic spinal cord injury (SCI) pain had significantly reduced EEG spectral reactivity in response to increased or decreased sensory input flowing into the thalamocortical network, as modulated by the eyes open and eyes closed states., Conclusion: The results provide further evidence for alterations in brain electric activity that may underlie the development of neuropathic pain following SCI.