Reduction in movement-evoked pain and fatigue during initial 30-minute transcutaneous electrical nerve stimulation treatment predicts transcutaneous electrical nerve stimulation responders in women with fibromyalgia

Peripheral nerve stimulation for lower-limb postoperative recovery: A systematic review and meta-analysis of randomized controlled trials

Patients undergoing lower-limb orthopedic surgery may experience multiple postoperative complications. Although peripheral nerve stimulation (PNS) is a promising non-pharmacological approach that has been used in lower-limb postoperative recovery, the clinical efficacy of PNS remains inconclusive. This study systematically searched three databases (PubMed, Embase, and Cochrane Library) for randomized controlled trials (RCTs) that examined the treatment effects of PNSs in patients who underwent lower-limb orthopedic surgery up to September 29, 2023. Two investigators independently identified studies, extracted data, and conducted meta-analyses with Review Manager 5.4. The outcomes were pain relief (measured by reductions in pain intensity and analgesic consumption) and functional improvements (range of motion [ROM] and length of hospitalization [LOH]). A total of 633 patients including 321 in the experimental groups and 312 in the control groups from eight RCTs were included. PNS showed no significant effect on pain intensity, while analgesic consumption was marginally significantly reduced in the experimental group. Furthermore, no significant differences were observed regarding functional improvements in ROM or LOH after the intervention. Although PNS had no significant effect on pain relief or functional improvements, the intervention exhibited a marginally significant reduction in analgesic consumption. Future trials should be conducted with larger sample sizes, longer follow-up periods, and more varied stimulation parameters.

Effectiveness of transcutaneous electrical nerve stimulation improves pain intensity, disability and quality of life in patients with fibromyalgia syndrome: a systematic review with meta-analysis

PURPOSE

The transcutaneous electrical nerve stimulation (TENS) is one of the most frequently electrophysical agents employed in reducing the impact of FMS. This meta-analysis intended to determine the effectiveness of TENS on pain, disability, and quality of life (QoL) in patients with FMS.

METHODS

According to PRISMA, we performed a meta-analysis (CRD42023456439), searching in PubMed Medline, PEDro, CINAHL Complete, Web of Science, and Scopus, since inception up to October 2023. This review focused on controlled clinical trials evaluating the effect of TENS on pain, disability, and QoL in patients with FMS. The pooled effect was estimated using Cohen's standardized mean difference (SMD) and its 95% confidence interval (95%CI).

RESULTS

Twelve studies, providing data from 944 patients, were included (PEDro score of 5.6 points). Meta-analyses showed that TENS interventions are effective in improving pain (SMD = -0.61; 95%CI -1 to -0.16); disability (SMD = -0.27; 95%CI -0.41 to -0.12); and physical dimension of QoL (SMD = 0.26; 95%CI 0.08 to 0.44). Additionally, when TENS is used as a unique therapy, it represents the best therapeutic option for improving pain, disability, and QoL.

CONCLUSIONS

This meta-analysis, including the largest number of studies, showed that TENS intervention is an effective therapy to reduce pain and disability and increase QoL in FMS patients.

The effect of transcutaneous electrical nerve stimulation on lumbar range of motion and lumbar fascia characteristics in healthy individuals

OBJECTIVES

To investigate the effect of Transcutaneous electrical nerve stimulation (TENS) on lumbar fascia thickness, lumbar flexion angle, and lumbar curvature in healthy people.

DESIGN

Randomized, clinical trial.

SUBJECTS

100 healthy individuals.

INTERVENTIONS

Participants were randomized into the active TENS group (n = 50) and placebo TENS group (n = 50). Subjects received 10 sessions of TENS in the lumbar region for 2 weeks.

MAIN MEASURES

Lumbar fascia thickness, lumbar flexion angle, and lumbar curvature examined by ultrasonography, flexible ruler, and spinal mouse three times (before and after the intervention sessions, and two weeks after the last intervention session-follow up) RESULTS: Subjects in the TENS group showed a significant reduction in lumbar fascia thickness (P ≤ 0.002), an increase in lumbar flexion angle (P = 0.000), and an increase in lumbar curvature angle (P = 0.000) before and after the intervention sessions. The results of the follow-up evaluations showed the stability of the changes in the mentioned variables.

CONCLUSION

The improvements in the lumbar fascia thickness and lumbar flexibility suggest that TENS may be effective in healthy subjects. Data indicate that biomechanical properties of lumbar fascia and lumbar flexibility are directly linked, and other mechanisms could be more influential in contributing to improvement.

Influence of Transcutaneous Electrical Nerve Stimulation (TENS) on Pressure Pain Thresholds and Conditioned Pain Modulation in a Randomized Controlled Trial in Women With Fibromyalgia

Transcutaneous electrical nerve stimulation (TENS) effectively reduces pain in fibromyalgia (FM). The purpose of this study was to examine the influence of TENS use on pressure pain thresholds (PPT) and conditioned pain modulation (CPM) in individuals with FM using data from the Fibromyalgia Activity Study with TENS trial (NCT01888640). Individuals with FM were randomly assigned to receive active TENS, placebo TENS, or no TENS for 4 weeks. A total of 238 females satisfied the per-protocol analysis among the active TENS (n = 76), placebo TENS (n = 68), and no TENS (n = 94) groups. Following 4 weeks of group allocation, the active TENS group continued for an additional 4 weeks of active TENS totaling 8 weeks (n = 66), the placebo and no TENS groups transitioned to receive 4 weeks of active TENS (delayed TENS, n = 161). Assessment of resting pain, movement-evoked pain (MEP), PPT, and CPM occurred prior to and following active, placebo, or no TENS. There were no significant changes in PPT or CPM among the active TENS, placebo TENS, or no TENS groups after 4 weeks. Individuals who reported clinically relevant improvements in MEP (≥30% decrease) demonstrated increases in PPT (P < .001), but not CPM, when compared to MEP non-responders. There were no significant correlations among the change in PPT or CPM compared to MEP and resting pain following active TENS use (active TENS + delayed TENS). PPT and CPM may provide insight to underlying mechanisms contributing to pain; however, these measures may not relate to self-reported pain symptoms. PERSPECTIVE: Pressure pain threshold increased in individuals with clinically relevant improvement (≥30%) in MEP, indicating the clinical relevance of PPT for understanding mechanisms contributing to pain. CPM was not a reliable indicator of treatment response in MEP responders.

Effects of the TENS device, Exopulse Mollii Suit, on pain related to fibromyalgia: An open-label study

Fibromyalgia is characterized by diffuse and chronic pain, that is often only partially alleviated by the available pharmacological treatments. Therefore, nonpharmacological interventions such as transcutaneous electrical stimulation (TENS) are highly needed to improve the quality of life of this population. However, the classical TENS devices offer a limited number of electrodes and are not adapted to this diffuse painful condition. For these reasons, we aimed to assess the effects of a new TENS device, the Exopulse Mollii Suit, that can stimulate up to 40 muscle groups integrated into pants and jackets and connected to a control unit. We report the data of 50 patients who received one session of active stimulation (pulse intensity 2 mA, and pulse frequency 20 Hz). Pain intensity was evaluated by means of the visual analogue scale (VAS), before (T0) and after the session (T1), and 24 h later (T24). Compared to baseline scores, a significant decrease in VAS was observed after the session (p<0.001), and 24 h later (p<0.001). T1 scores were significantly lower than T24 scores (p<0.001). Therefore, this new system seems to exert analgesic effects whose mechanisms primarily evoke the theory of "gate control". The effects were transient and started to decrease the following day, highlighting the need for additional studies to better evaluate the long-term effects of this intervention on pain, mood, and quality of life.

Treating fibromyalgia with electrical neuromodulation: A systematic review and meta-analysis

OBJECTIVE

Several types of electrical neuromodulation (such as transcranial direct current stimulation, tDCS; transcutaneous electrical nerve stimulation) have been applied in the treatment of fibromyalgia. These trials had different outcome measurements, such as subjective pain, pain threshold, depression, anxiety, and functioning. We intended to integrate data from different trials into a meta-analysis to clearly present the clinical value of electrical neuromodulation in fibromyalgia.

METHODS

A systematic review and meta-analysis of randomized controlled trials comparing the effect of all types of electrical neuromodulation in patients with fibromyalgia was conducted. The main outcome was subjective pain; the secondary outcomes included depression, anxiety, and functioning.

RESULTS

Twenty-five studies and 1061 fibromyalgia patients were included in the quantitative analysis. Active electrical neuromodulation and active tDCS both showed significant effects on subjective pain, depression, and functioning. For different anode tDCS electrode positions, only F3-F4 revealed a significant effect on depression. Meta-regression tDCS effects on depression were significantly associated with age.

CONCLUSIONS

Electrical neuromodulation is significantly effective in treating pain, depression, and functioning in patients with fibromyalgia.

SIGNIFICANCE

The results may help clinicians to arrange effective treatment plans for patients with fibromyalgia, especially in those patients who reveal limited response to pharmacotherapy and psychotherapy.

Intervention delivery for embedded pragmatic clinical trials: Development of a tool to measure complexity

BACKGROUND

Conducting an embedded pragmatic clinical trial in the workflow of a healthcare system is a complex endeavor. The complexity of the intervention delivery can have implications for study planning, ability to maintain fidelity to the intervention during the trial, and/or ability to detect meaningful differences in outcomes.

METHODS

We conducted a literature review, developed a tool, and conducted two rounds of phone calls with NIH Pragmatic Trials Collaboratory Demonstration Project principal investigators to develop the Intervention Delivery Complexity Tool. After refining the tool, we piloted it with Collaboratory demonstration projects and developed an online version of the tool using the R Shiny application (https://duke-som.shinyapps.io/ICT-ePCT/).

RESULTS

The 6-item tool consists of internal and external factors. Internal factors pertain to the intervention itself and include workflow, training, and the number of intervention components. External factors are related to intervention delivery at the system level including differences in healthcare systems, the dependency on setting for implementation, and the number of steps between the intervention and the outcome.

CONCLUSION

The Intervention Delivery Complexity Tool was developed as a standard way to overcome communication challenges of intervention delivery within an embedded pragmatic trial. This version of the tool is most likely to be useful to the trial team and its health system partners during trial planning and conduct. We expect further evolution of the tool as more pragmatic trials are conducted and feedback is received on its performance outside of the NIH Pragmatic Trials Collaboratory.

The Fibromyalgia Transcutaneous Electrical Nerve Stimulation in Physical Therapy Study Protocol: A Multisite Embedded Pragmatic Trial

OBJECTIVES

Transcutaneous electrical nerve stimulation (TENS) is a nonpharmacological intervention that provides an electrical current through the skin to produce analgesia. The primary purpose of this study is to examine if the addition of TENS to routine physical therapy improves movement-evoked pain in individuals with fibromyalgia in a physical therapy clinical setting.

METHODS

Fibromyalgia TENS in Physical Therapy Study is a phase III embedded pragmatic clinical trial funded through the National Institutes of Health Helping to End Addiction Long-Term Initiative. This trial will utilize a randomized cluster design that includes more than 110 physical therapists in 24 to 30 physical therapy clinics within 6 health care systems and 7 states. Clinics will be randomized to TENS or No-TENS, stratified by health care system and clinic size. The plan is to enroll 600 participants, with all participants completing physical therapy as prescribed by their physical therapist. Participants at TENS clinics will utilize TENS for a minimum of 2-hour per day while at the physical therapy clinic and at home when active. The primary outcome is reduction in movement-evoked pain from baseline to day 60 on an 11-point numeric rating scale when participants sit and stand 5 times (Sit and Stand Test). Secondary outcomes include resting pain and fatigue, pain interference, fibromyalgia disease activity, movement-evoked fatigue, multidimensional assessment of fatigue, rapid assessment of physical activity, patient global impression of change, and common data elements shared across studies supported through the Helping to End Addiction Long-Term Initiative.

IMPACT

The findings from this study will provide effectiveness data on TENS for individuals with fibromyalgia for health care policymakers, clinicians, and insurers. Data from this study will also inform future pragmatic trials for nonpharmacological interventions and chronic musculoskeletal pain conditions.

Using TENS for Pain Control: Update on the State of the Evidence

Transcutaneous electrical nerve stimulation (TENS) is a non-pharmacological intervention used in the treatment of acute and chronic pain conditions. The first clinical studies on TENS were published over 50 years ago, when effective parameters of stimulation were unclear and clinical trial design was in its infancy. Over the last two decades, a better understanding of the mechanisms underlying TENS efficacy has led to the development of an adequate dose and has improved outcome measure utilization. The continued uncertainty about the clinical efficacy of TENS to alleviate pain, despite years of research, is related to the quality of the clinical trials included in systematic reviews. This summary of the evidence includes only trials with pain as the primary outcome. The outcomes will be rated as positive (+), negative (-), undecided (U), or equivalent to other effective interventions (=). In comparison with our 2014 review, there appears to be improvement in adverse events and parameter reporting. Importantly, stimulation intensity has been documented as critical to therapeutic success. Examinations of the outcomes beyond resting pain, analgesic tolerance, and identification of TENS responders remain less studied areas of research. This literature review supports the conclusion that TENS may have efficacy for a variety of acute and chronic pain conditions, although the magnitude of the effect remains uncertain due to the low quality of existing literature. In order to provide information to individuals with pain and to clinicians treating those with pain, we suggest that resources for research should target larger, high-quality clinical trials including an adequate TENS dose and adequate timing of the outcome and should monitor risks of bias. Systematic reviews and meta-analyses should focus only on areas with sufficiently strong clinical trials that will result in adequate sample size.

The Influence of Opioids on Transcutaneous Electrical Nerve Stimulation Effects in Women With Fibromyalgia

Transcutaneous electrical nerve stimulation (TENS) uses endogenous opioids to produce analgesia, and effectiveness can be reduced in opioid-tolerant individuals'. We examined TENS effectiveness (primary aim), and differences in fibromyalgia symptoms (secondary aim), in women with fibromyalgia regularly taking opioid (RTO) medications compared with women not- regularly taking opioids (not-RTO). Women (RTO n = 79; not-RTO not-n = 222) with fibromyalgia with daily pain levels ≥4 were enrolled and categorized into RTO (taking opioids at least 5 of 7 days in last 30 days) or not-RTO groups. Participants were categorized into tramadol n = 52 (65.8%) and other opioids n = 27 (34.2%) for the RTO group. Participants were phenotyped across multiple domains including demographics, fibromyalgia characteristics pain, fatigue, sleep, psychosocial factors, and activity. Participants were randomized to active TENS (n = 101), placebo TENS (n = 99), or no TENS (n = 99) for 1-month with randomization stratified by opioid use. Active TENS was equally effective in movement-evoked pain in those in the RTO and not-RTO groups. Women with fibromyalgia in the RTO group were older (P = .002), lower-income (P = .035), more likely to smoke (P = .014), and more likely to report depression (P = .013), hypertension (P = .005) or osteoarthritis (P = .027). The RTO group demonstrated greater bodily pain on SF-36 (P = .005), lower quality of life on the physical health component of the SF-36 (P = .040), and greater fatigue (MAF-ADL P = .047; fatigue with sit to stand test (P = .047) These differences were small of and unclear clinical significance. In summary, regular use of opioid analgesics does not interfere with the effectiveness of TENS for movement-evoked pain. Clinical Trial Registration Number: NCT01888640. PERSPECTIVE: Individuals treated with mixed frequency TENS at a strong but comfortable intensity that was taking prescription opioid analgesics showed a significant reduction in movement-evoked pain and fatigue. These data support the use of TENS, using appropriate parameters of stimulation, as an intervention for individuals with fibromyalgia taking opioid analgesics.

Characterising the Features of 381 Clinical Studies Evaluating Transcutaneous Electrical Nerve Stimulation (TENS) for Pain Relief: A Secondary Analysis of the Meta-TENS Study to Improve Future Research

Background and Objectives: Characterising the features of methodologies, clinical attributes and intervention protocols, of studies is valuable to advise directions for research and practice. This article reports the findings of a secondary analysis of the features from studies screened as part of a large systematic review of TENS (the meta-TENS study). Materials and Methods: A descriptive analysis was performed on information associated with methodology, sample populations and intervention protocols from 381 randomised controlled trials (24,532 participants) evaluating TENS delivered at a strong comfortable intensity at the painful site in adults with pain, irrespective of diagnosis. Results: Studies were conducted in 43 countries commonly using parallel group design (n = 334) and one comparator group (n = 231). Mean ± standard deviation (SD) study sample size (64.05 ± 58.29 participants) and TENS group size (27.67 ± 21.90 participants) were small, with only 13 of 381 studies having 100 participants or more in the TENS group. Most TENS interventions were ‘high frequency’ (>10 pps, n = 276) and using 100 Hz (109/353 reports that stated a pulse frequency value). Of 476 comparator groups, 54.2% were active treatments (i.e., analgesic medication(s), exercise, manual therapies and electrophysical agents). Of 202 placebo comparator groups, 155 used a TENS device that did not deliver currents. At least 216 of 383 study groups were able to access other treatments whilst receiving TENS. Only 136 out of 381 reports included a statement about adverse events. Conclusions: Clinical studies on TENS are dominated by small parallel group evaluations of high frequency TENS that are often contaminated by concurrent treatment(s). Study reports tended focus on physiological and clinical implications rather than the veracity of methodology and findings. Previously published criteria for designing and reporting TENS studies were neglected and this should be corrected in future research using insights gleaned from this analysis.

Advances in the management of fibromyalgia: what is the state of the art?

INTRODUCTION

Fibromyalgia (FM) is a chronic pain syndrome associated with fatigue, insomnia, dyscognition, and emotional distress. Critical illness mechanisms include central sensitization to nociceptive and non-nociceptive stimuli often resulting in hypersensitivity to all sensory input.

AREAS COVERED

The clinical presentation of FM can vary widely and therefore requires therapies tailored to each patient's set of symptoms. This manuscript examines currently prescribed therapeutic approaches supported by empirical evidence as well as promising novel treatments. Although pharmacological therapy until now has been only moderately effective for FM symptoms, it represents a critical component of every treatment plan.

EXPERT OPINION

Currently approved pharmacological therapies for FM symptoms have limited but proven effectiveness. Novel therapies with cannabinoids and naltrexone appear promising. Recent functional imaging studies of FM have discovered multiple brain network abnormalities that may provide novel targets for mechanism-based therapies. Future treatment approaches, however, need to improve more than clinical pain but also other FM domains like fatigue, insomnia, and distress.

Efficacy and safety of transcutaneous electrical nerve stimulation (TENS) for acute and chronic pain in adults: a systematic review and meta-analysis of 381 studies (the meta-TENS study)

OBJECTIVE

To investigate the efficacy and safety of transcutaneous electrical nerve stimulation (TENS) for relief of pain in adults.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Medline, Cochrane Central, Embase (and others) from inception to July 2019 and updated on 17 May 2020.

ELIGIBILITY CRITERIA FOR STUDY SELECTION

Randomised controlled trials (RCTs) comparing strong non-painful TENS at or close to the site of pain versus placebo or other treatments in adults with pain, irrespective of diagnosis.

DATA EXTRACTION AND SYNTHESIS

Reviewers independently screened, extracted data and assessed risk of bias (RoB, Cochrane tool) and certainty of evidence (Grading and Recommendations, Assessment, Development and Evaluation). Mean pain intensity and proportions of participants achieving reductions of pain intensity (≥30% or >50%) during or immediately after TENS. Random effect models were used to calculate standardised mean differences (SMD) and risk ratios. Subgroup analyses were related to trial methodology and characteristics of pain.

RESULTS

The review included 381 RCTs (24 532 participants). Pain intensity was lower during or immediately after TENS compared with placebo (91 RCTs, 92 samples, n=4841, SMD=-0·96 (95% CI -1·14 to -0·78), moderate-certainty evidence). Methodological (eg, RoB, sample size) and pain characteristics (eg, acute vs chronic, diagnosis) did not modify the effect. Pain intensity was lower during or immediately after TENS compared with pharmacological and non-pharmacological treatments used as part of standard of care (61 RCTs, 61 samples, n=3155, SMD = -0·72 (95% CI -0·95 to -0·50], low-certainty evidence). Levels of evidence were downgraded because of small-sized trials contributing to imprecision in magnitude estimates. Data were limited for other outcomes including adverse events which were poorly reported, generally mild and not different to comparators.

CONCLUSION

There was moderate-certainty evidence that pain intensity is lower during or immediately after TENS compared with placebo and without serious adverse events.

PROSPERO REGISTRATION NUMBER

CRD42019125054.

Virtual Reality-Based Therapy Reduces the Disabling Impact of Fibromyalgia Syndrome in Women: Systematic Review with Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Virtual reality-based therapy (VRBT) is a novel therapeutic approach to be used in women with fibromyalgia syndrome (FMS). The aim of our study is to assess the effect of VRBT to reduce the impact of FMS in outcomes such as pain, dynamic balance, aerobic capacity, fatigue, quality of life (QoL), anxiety and depression.

METHODS

Systematic review with meta-analysis was conducted from a bibliographic search in PubMed, Scopus, PEDro, Web of Science and CINAHL until April 2021 in accordance with PRISMA guidelines. We included randomized controlled trials (RCTs) that compare VRBT versus others to assess the mentioned outcomes in women with FMS. Effect size was calculated with standardized mean difference (SMD) and its 95% confidence interval (95% CI).

RESULTS

Eleven RCTs involving 535 women with FMS were included. Using the PEDro scale, the mean methodological quality of the included studies was moderate (6.63 ± 0.51). Our findings showed an effect of VRBT on the impact of FMS (SMD -0.62, 95% CI -0.93 to -0.31); pain (SMD -0.45, 95% CI -0.69 to -0.21); dynamic balance (SMD -0.76, 95% CI -1.12 to -0.39); aerobic capacity (SMD 0.32, 95% CI 0.004 to 0.63); fatigue (SMD -0.58, 95% CI -1.02 to -0.14); QoL (SMD 0.55, 95% CI 0.3 to 0.81); anxiety (SMD -0.47, 95% CI -0.91 to -0.03) and depression (SMD -0.46, 95% CI -0.76 to -0.16).

CONCLUSIONS

VRBT is an effective therapy that reduces the impact of FMS, pain, fatigue, anxiety and depression and increases dynamic balance, aerobic capacity and quality of life in women with FMS. In addition, VRBT in combination with CTBTE showed a large effect in reducing the impact of FMS and fatigue and increasing QoL in these women.

Enhancing the use of EHR systems for pragmatic embedded research: lessons from the NIH Health Care Systems Research Collaboratory

OBJECTIVE

We identified challenges and solutions to using electronic health record (EHR) systems for the design and conduct of pragmatic research.

MATERIALS AND METHODS

Since 2012, the Health Care Systems Research Collaboratory has served as the resource coordinating center for 21 pragmatic clinical trial demonstration projects. The EHR Core working group invited these demonstration projects to complete a written semistructured survey and used an inductive approach to review responses and identify EHR-related challenges and suggested EHR enhancements.

RESULTS

We received survey responses from 20 projects and identified 21 challenges that fell into 6 broad themes: (1) inadequate collection of patient-reported outcome data, (2) lack of structured data collection, (3) data standardization, (4) resources to support customization of EHRs, (5) difficulties aggregating data across sites, and (6) accessing EHR data.

DISCUSSION

Based on these findings, we formulated 6 prerequisites for PCTs that would enable the conduct of pragmatic research: (1) integrate the collection of patient-centered data into EHR systems, (2) facilitate structured research data collection by leveraging standard EHR functions, usable interfaces, and standard workflows, (3) support the creation of high-quality research data by using standards, (4) ensure adequate IT staff to support embedded research, (5) create aggregate, multidata type resources for multisite trials, and (6) create re-usable and automated queries.

CONCLUSION

We are hopeful our collection of specific EHR challenges and research needs will drive health system leaders, policymakers, and EHR designers to support these suggestions to improve our national capacity for generating real-world evidence.