Effects of Virtual Walking Treatment on Spinal Cord Injury–Related Neuropathic Pain: Pilot Results and Trends Related to Location of Pain and at-level Neuronal Hypersensitivity

Cortical Mechanisms Underlying Immersive Interactive Virtual Walking Treatment for Amelioration of Neuropathic Pain after Spinal Cord Injury: Findings from a Preliminary Investigation of Thalamic Inhibitory Function

BACKGROUND

Neuropathic pain following spinal cord injury (SCI) affects approximately 60% of individuals with SCI. Effective pharmacological and non-pharmacological treatments remain elusive. We recently demonstrated that our immersive virtual reality walking intervention (VRWalk) may be effective for SCI NP. Additionally, we found that SCI NP may result from a decrease in thalamic γ-aminobutyric-acid (GABA), which disturbs central sensorimotor processing.

OBJECTIVE

While we identified GABAergic changes associated with SCI NP, a critical outstanding question is whether a decrease in SCI NP generated by our VRWalk intervention causes GABA content to rise.

METHOD

A subset of participants (n = 7) of our VRWalk trial underwent magnetic resonance spectroscopy pre- and post-VRWalk intervention to determine if the decrease in SCI NP is associated with an increase in thalamic GABA.

RESULTS

The findings revealed a significant increase in thalamic GABA content from pre- to post-VRWalk treatment.

CONCLUSION

While the current findings are preliminary and should be interpreted with caution, pre- to post-VRWalk reductions in SCI NP may be mediated by pre- to post-treatment increases in thalamic GABA by targeting and normalizing maladaptive sensorimotor cortex reorganization. Understanding the underlying mechanisms of pain recovery can serve to validate the efficacy of home-based VR walking treatment as a means of managing pain following SCI. Neuromodulatory interventions aimed at increasing thalamic inhibitory function may provide more effective pain relief than currently available treatments.

Effectiveness of Virtual Reality-Based Interventions for Managing Chronic Pain on Pain Reduction, Anxiety, Depression and Mood: A Systematic Review

(1) Background: Patients diagnosed with chronic pain suffer from long-term pain, which negatively affects their daily lives and mental health. Virtual reality (VR) technologies are considered a therapeutic tool to manage pain perception and mental health conditions. This systematic review aimed to appraise the efficacy of VR in improving pain intensity, anxiety, depression and mood among patients with chronic pain; (2) Methods: Five electronic databases were systematically searched using the terms representing VR and chronic pain. Quality assessment was conducted using Cochrane Collaboration’s tool and Newcastle-Ottawa scale; (3) Results: Seventeen peer-reviewed articles were included in this review. It was found that VR was able to reduce pain intensity in patients with phantom limb pain, chronic headache, chronic neck pain and chronic low-back pain. The effects of VR on the improvement of anxiety, depression and mood were not determined due to the inadequate amount of clinical evidence; (4) Conclusions: VR, especially immersive VR, improves pain outcomes and its effects may vary depending on the approach and study design. More research is still needed to investigate the clinical use of VR in patients with chronic pain.

An Exploratory EEG Analysis on the Effects of Virtual Reality in People with Neuropathic Pain Following Spinal Cord Injury

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.

Immersive interactive virtual walking reduces neuropathic pain in spinal cord injury: findings from a preliminary investigation of feasibility and clinical efficacy

ABSTRACT

Chronic neuropathic pain (NP) is a common and often debilitating secondary condition for persons with spinal cord injury (SCI) and is minimally responsive to existing pharmacological and nonpharmacological treatments. The current preliminary investigation describes the feasibility and initial comparative efficacy of an interactive virtual reality walking intervention, which is a novel extension of visual feedback/illusory walking therapies shown to reduce SCI NP. Virtual reality walking intervention builds on previous research by, for the first time, allowing individuals with SCI NP to volitionally control virtual gait to interact with a fully immersive virtual environment. The current pilot study compared this interactive, virtual walking intervention to a passive, noninteractive virtual walking condition (analogous to previous illusory walking interventions) in 27 individuals with complete paraplegia (interactive condition, n = 17; passive condition, n = 10; nonrandomized design). The intervention was delivered over 2 weeks in individuals' homes. Participants in the interactive condition endorsed significantly greater reductions in NP intensity and NP-related activity interference preintervention to postintervention. Notable improvements in mood and affect were also observed both within individual sessions and in response to the full intervention. These results, although preliminary, highlight the potentially potent effects of an interactive virtual walking intervention for SCI NP. The current study results require replication in a larger, randomized clinical trial and may form a valuable basis for future inquiry regarding the mechanisms and clinical applications of virtual walking therapies.

The CanPain SCI clinical practice guidelines for rehabilitation management of neuropathic pain after spinal cord injury: 2021 update

STUDY DESIGN

Clinical practice guidelines.

OBJECTIVES

The objective was to update the 2016 version of the Canadian clinical practice guidelines for the management of neuropathic pain in people with spinal cord injury (SCI).

SETTING

The guidelines are relevant for inpatient, outpatient and community SCI rehabilitation settings in Canada.

METHODS

The guidelines were updated 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 identified and reviewed 46 additional relevant articles published since the last version of the guidelines. The panel agreed on 3 new screening and diagnosis recommendations and 8 new treatment recommendations. Two key changes to these treatment recommendations included the introduction of general treatment principles and a new treatment recommendation classification system. No new recommendations to model of care were made.

CONCLUSIONS

The CanPainSCI recommendations for the management of neuropathic pain after SCI should be used to inform practice.

A Therapeutic Matrix: Virtual Reality as a Clinical Tool for Spinal Cord Injury-Induced Neuropathic Pain

Neuropathic pain (NP) is a chronic, debilitating, and resistant form of pain. The onset rate of NP following spinal cord injuries (SCI) is high and may reduce the quality of life more than the sensorimotor loss itself. The long-term ineffectiveness of current treatments in managing symptoms and counteracting maladaptive plasticity highlights the need to find alternative therapeutic approaches. Virtual reality (VR) is possibly the best way to administer the specific illusory or reality-like experience and promote behavioral responses that may be effective in mitigating the effects of long-established NP. This approach aims to promote a more systematic adoption of VR-related techniques in pain research and management procedures, highlighting the encouraging preliminary results in SCI. We suggest that the multisensory modulation of the sense of agency and ownership by residual body signals may produce positive responses in cases of brain-body disconnection. First, we focus on the transversal role embodiment and how multisensory and environmental or artificial stimuli modulate illusory sensations of bodily presence and ownership. Then, we present a brief overview of the use of VR in healthcare and pain management. Finally, we discus research experiences which used VR in patients with SCI to treating NP, including the most recent combinations of VR with further stimulation techniques.

Pain Reduction after Short Exposure to Virtual Reality Environments in People with Spinal Cord Injury

Emerging literature suggests that virtual reality (VR) may be a viable therapy for neuropathic pain (NP). This pilot study aimed to investigate the immediate effect of VR in reducing NP in people with spinal cord injury (SCI). Eight individuals with chronic NP after SCI were recruited and underwent consecutive exposure to scenery and somatic virtual environments (VE). The numeric rating scale (NRS) was used to assess pain before and after exposure to each VE. The Immersive Tendencies Questionnaire (ITQ) and Presence Questionnaire (UQO-PQ) were used to investigate the interaction between reported pain relief post-intervention with immersion and presence. There was a significant reduction in pain levels (5.1 ± 0.4, mean ± SEM) after short exposure to the scenery (3.1 ± 0.7, p = 0.04) and somatic VE (3.0 ± 0.7, p = 0.04), with no difference between intervention types (p = 0.56). There was a statistically significant negative correlation between the total ITQ score and the change in NRS after the scenery VR intervention (r_s = 0.743, p = 0.035). PQ scores showed no significant correlation with changes in pain following either intervention type. We found that short-term exposure to VR environments results in a reduction in chronic NP intensity in people with SCI.

Relationship between pain, fatigue, and physical activity levels during a technology-based physical activity intervention

Objective: The majority of individuals with spinal cord injury (SCI) experience chronic pain. Chronic pain can be difficult to manage because of variability in the underlying pain mechanisms. More insight regarding the relationship between pain and physical activity (PA) is necessary to understand pain responses during PA. The objective of this study is to explore possible relationships between PA levels and secondary conditions including pain and fatigue.Design: Prospective cohort analysis of a pilot study.Setting: Community.Participants: Twenty individuals with SCI took part in the study, and sixteen completed the study.Interventions: Mobile-health (mHealth) based PA intervention for two-months during the three-month study.Outcome measures: Chronic Pain Grade Scale (CPGS) questionnaire, The Wheelchair User's Shoulder Pain Index (WUSPI), Fatigue Severity Scale (FSS), and PA levels measured by the mHealth system.Results: A positive linear relationship was found between light-intensity PA and task-specific pain. However, the relationship between moderate-intensity PA and pain interference was best represented by a curvilinear relationship (polynomial regression of second order). Light-intensity PA showed positive, linear correlation with fatigue at baseline. Moderate-intensity PA was not associated with fatigue during any phase of the study.Conclusion: Our results indicated that PA was associated with chronic pain, and the relationship differed based on intensity and amount of PA performed. Further research is necessary to refine PA recommendations for individuals with SCI who experience chronic pain.Trial registration: ClinicalTrials.gov identifier: NCT03773692.

Go Virtual to Get Real: Virtual Reality as a Resource for Spinal Cord Treatment

Increasingly, refined virtual reality (VR) techniques allow for the simultaneous and coherent stimulation of multiple sensory and motor domains. In some clinical interventions, such as those related to spinal cord injuries (SCIs), the impact of VR on people's multisensory perception, movements, attitudes, and even modulations of socio-cognitive aspects of their behavior may influence every phase of their rehabilitation treatment, from the acute to chronic stages. This work describes the potential advantages of using first-person-perspective VR to treat SCIs and its implications for manipulating sensory-motor feedback to alter body signals. By situating a patient with SCI in a virtual environment, sensorial perceptions and motor intention can be enriched into a more coherent bodily experience that also promotes processes of neural regeneration and plasticity. In addition to the great potential of research, the most significant areas of interest concern is managing neuropathic pain, motor rehabilitation, and psychological well-being.

Virtual reality for the treatment of neuropathic pain in people with spinal cord injuries: A scoping review

Context: Virtual and augmented imagery are emerging technologies with potential to reduce the severity and impact of neuropathic pain in people with spinal cord injury (SCI).Objective: We aimed to identify and discuss studies using virtual and augmented reality applications for the management of neuropathic pain in people with spinal cord injury.Methods (data sources, data extraction): A systematic literature search was conducted using PRISMA scoping review guidelines. Articles were searched in PubMed, Embase and Web of Science databases using search terms relating to SCI, virtual and augmented reality and neuropathic pain. With no strong evidence for visual imagery in the treatment of pain in SCI patients, we selected exploratory, feasibility and more rigorous methodologies such as randomized controlled trials and case-control studies. We only selected studies evaluating the effects of visual imagery on neuropathic pain at or below the spinal cord injury level.Results: Of 60 articles located, we included nine articles involving 207 participants. All studies were exploratory using head-mounted devices or 3D and 2D screens with virtual walking or limb movement imagery. Outcomes included pain sensitivity, motor function and body ownership. Eight of the nine studies reported significant reductions in neuropathic pain intensity. However, given small sample sizes in all studies, results may be unreliable.Conclusion: Although the number of studies and individual sample sizes are small, these initial findings are promising. Given the limited options available for the effective treatment of neuropathic SCI pain and early evidence of efficacy, they provide valuable incentive for further research.

The short-term effects of head-mounted virtual-reality on neuropathic pain intensity in people with spinal cord injury pain: a randomised cross-over pilot study

STUDY DESIGN

Within-subject, randomised cross-over trial.

OBJECTIVES

To determine whether a commercially available 3D head-mounted (HMD) virtual reality (VR) device results in significant reductions in neuropathic pain compared to using a 2D screen device in people with spinal cord injury (SCI).

SETTING

Greenwich Hospital, Sydney, Australia.

METHODS

Sixteen men with established SCI and chronic neuropathic pain participated in a single-session randomised cross-over trial. We compared the effects of 3D HMD VR and a 2D screen application on SCI neuropathic pain intensity and levels of perceived presence.

RESULTS

Participants reported significantly lower pain intensity after 3D HMD VR compared to 2D screen application (1.9 ± SD 1.8 versus 3.4 ± SD 1.6, mean 95% CI: 1.5, P < 0.0001). Participants reported significantly higher perceived levels of presence with the 3D HMD VR compared to 2D screen of (49.6 ± SD 8.9 versus 32.8 ± SD 11.1, mean 95% CI: 16.6, P < 0.0001). Increased perceived presence was associated with significantly lower pain intensity regardless of randomised sequencing of the two conditions (mean 95% CI: 0.06, P = 0.005). Effect size for pain reduction using 3D HMD VR was 0.80.

CONCLUSIONS

We suggest that 3D HMD VR may provide neuropathic pain relief for people with SCI. Given the lack of cybersickness and ease of access, we propose that immersive VR could be a helpful adjunct to current pharmacotherapy. Further research is required to show that VR can be effective for more long-term reductions in SCI pain.

Central Nervous System Reorganization and Pain After Spinal Cord Injury: Possible Targets for Physical Therapy-A Systematic Review of Neuroimaging Studies

BACKGROUND

Pain is one of the main symptoms associated with spinal cord injury (SCI) and can be associated with changes to the central nervous system (CNS).

PURPOSE

This article provides an overview of the evidence relating to CNS changes (structural and functional) associated with pain in SCIs.

DATA SOURCES

A systematic review was performed, according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations, on PubMed, Embase, and Web of Science in March 2018.

STUDY SELECTION

Studies were selected if they concerned changes in the CNS of patients with SCI, regardless of the type of imagery.

DATA EXTRACTION

Data were extracted by 2 blinded reviewers.

DATA SYNTHESIS

There is moderate evidence for impaired electroencephalographic function and metabolic abnormalities in the anterior cingulate in patients experiencing pain. There is preliminary evidence that patients with pain have morphological and functional changes to the somatosensory cortex and alterations to thalamic metabolism. There are conflicting data regarding the relationships between lesion characteristics and pain. In contrast, patients without pain can display protective neuroplasticity.

LIMITATIONS AND CONCLUSION

Further studies are required to elucidate fully the relationships between pain and neuroplasticity in patients with SCIs. However, current evidence might support the use of physical therapist treatments targeting CNS plasticity in patients with SCI pain.

Efficacy of Virtual Reality Rehabilitation after Spinal Cord Injury: A Systematic Review

Background

Spinal cord injury (SCI) is often associated with long-term impairments related to functional limitations in the sensorimotor system. The use of virtual reality (VR) technology may lead to increased motivation and engagement, besides allowing a wide range of possible tasks/exercises to be implemented in rehabilitation programs. The present review aims to investigate the possible benefits and efficacy of VR-based rehabilitation in individuals with SCI.

Methods

An electronically systematic search was performed in multiple databases (PubMed, BVS, Web of Science, Cochrane Central, and Scielo) up to May 2019. MESH terms and keywords were combined in a search strategy. Two reviewers independently selected the studies in accordance with eligibility criteria. The PEDro scale was used to score the methodological quality and risk of bias of the selected studies.

Results

Twenty-five studies (including 482 participants, 47.6 ± 9.5 years, 73% male) were selected and discussed. Overall, the studies used VR devices in different rehabilitation protocols to improve motor function, driving skills, balance, aerobic function, and pain level, as well as psychological and motivational aspects. A large amount of heterogeneity was observed as to the study design, VR protocols, and outcome measures used. Only seven studies (28%) had an excellent/good quality of evidence. However, substantial evidence for significant positive effects associated with VR therapy was found in most of the studies (88%), with no adverse events (88%) being reported.

Conclusion

Although the current evidence is limited, the findings suggest that VR-based rehabilitation in subjects with SCI may lead to positive effects on aerobic function, balance, pain level, and motor function recovery besides improving psychological/motivational aspects. Further high-quality studies are needed to provide a guideline to clinical practice and to draw robust conclusions about the potential benefits of VR therapy for SCI patients. Protocol details are registered on PROSPERO (registration number: CRD42016052629).

Virtual reality for spinal cord injury-associated neuropathic pain: Systematic review

BACKGROUND

Treatment of spinal cord injury (SCI)-associated neuropathic pain is challenging, with limited efficacy and no definitive options, and SCI patients often show resistance to pharmacologic treatment. Virtual reality (VR) therapy is a non-invasive, non-pharmacologic alternative with minimal adverse effects.

OBJECTIVE

To investigate the effect of VR therapy on SCI-associated neuropathic pain in a systematic review.

METHODS

Articles needed to 1) be written in English; 2) include adult subjects, with at least half the study population with a SCI diagnosis; 3) involve any form of VR therapy; and 4) assess neuropathic pain by quantitative outcome measures. Articles were searched in MEDLINE/PubMed, CINAHL^®, EMBASE, and PsycINFO up to April 2018. Reference lists of retrieved articles were hand-searched. Methodologic quality was assessed by the Physiotherapy Evidence Database Score (PEDro) for randomized controlled trials and Modified Downs and Black Tool (D&B) for all other studies. Level of evidence was determined by using a modified Sackett scale.

RESULTS

Among 333 studies identified, 9 included in this review (n=150 participants) evaluated 4 methods of VR therapy (virtual walking, VR-augmented training, virtual illusion, and VR hypnosis) for treating neuropathic pain in SCI patients. Each VR method reduced neuropathic pain: 4 studies supported virtual walking, and the other 3 VR methods were each supported by a different study. Combined treatment with virtual walking and transcranial direct current stimulation was the most effective. The quality of studies was a major limitation.

CONCLUSION

VR therapy could reduce SCI-associated neuropathic pain, although the clinical significance of this analgesic effect is unclear. Clinical trials evaluating VR therapy as standalone and/or adjunct therapy for neuropathic pain in SCI patients are warranted.