Efficacy of diadynamic currents as an adjunct to exercise to manage symptoms of knee osteoarthritis in adults: A randomized controlled clinical trial.

OBJECTIVE: To investigate the effect of diadynamic currents administered prior to exercises on pain and disability in patients with osteoarthritis of the knee. DESIGN: A randomized-controlled trial. SETTING: Special Rehabilitation Services in Taboão da Serra. PARTICIPANTS: Patients with bilateral knee osteoarthritis. INTERVENTION: Participants were randomly allocated to Group I (diadynamic currents and exercises; n = 30, 60 knees) or Group II (exercises alone; n = 30, 60 knees) and were treated three times a week for 8 weeks. MAIN OUTCOME MEASURES: The primary outcome measures were change in knee pain evaluated by visual analog scale and disability Index Score (Lequesne). Secondary outcomes included change in mobility (Timed Up and Go test), range of motion (goniometer), muscle strength (dynamometer), a composite score for pain and disability (Western Ontario and McMaster Universities Osteoarthritis questionnaire), and a drug diary to measure consumption of rescue pain medication (paracetamol). All measurements were collected at baseline, 8 weeks, and 6 months from baseline (follow-up). RESULTS: There were 60 participants with a mean (SD) age of 63.40 (8.20) years. Between-group differences in the follow-up (8 weeks and 6 months) were observed for pain at rest, pain during activities of daily living and disability. There was improvement in Group I that was maintained for the three variables 6 months after treatment. Mean difference for pain at rest was -3.08 points (95% confidence interval -4.13; -2.02), p < 0.01 with an effect size of 1.4; mean difference for pain during activities of daily living was -2.40 points (95% confidence interval -3.34; -1.45), p < 0.01 with an effect size of 1.24; and mean difference for disability was -4.08 points (95% confidence interval -5.89; -2.26), p < 0.01 with an effect size of 1.04. CONCLUSION: Patients with symptomatic knee osteoarthritis receiving 8 weeks of treatment with diadynamic currents as an adjunct to a program of exercises had significantly greater improvements in pain and disability than those receiving exercises alone. Beneficial effects were sustained for 6 months.

Efficacy of cranial electrotherapy stimulation in patients with burning mouth syndrome: a randomized, controlled, double-blind pilot study.

Background: The Burning mouth syndrome (BMS) is a chronic pain syndrome characterized by a burning sensation in the oral mucous membranes. The etiology and pathophysiology of BMS is largely unexplained. To date, there is no evidence-based treatment strategy for BMS. Cranial electrical stimulation (CES) represents a non-invasive treatment option with a low side effect profile that is approved for the treatment of pain, depression, anxiety disorder and insomnia. It has shown efficacy in studies for chronic pain such as fibromyalgia and neuropathic pain after spinal cord injury. This study aimed to investigate the therapeutic effectiveness of CES in combination with local transcutaneous electrical nerve stimulation (TENS) as an adjunct therapy in patients with BMS compared to sham stimulation. Methods: This randomized, double-blind, sham-controlled pilot study enrolled 22 patients, aged 18 years and over, with the diagnosis of BMS meeting the ICHD-3 criteria from August 2020 to June 2021. The study duration was 4 weeks (28 days) per participant. After randomization, the active group participants (n = 11) received a 100 µA CES treatment for 60 min a day whereas the devices in the Sham group did not emit electricity. Simple linear regression was used to determine whether the interventions promoted significant differences in pain intensity. Results: The linear regression showed that the period of stimulation significantly predicted decrease in the intensity of pain in the active group [ß = -0.036; t(26) = -7.219; p < 0.001] as in the sham group [ß = -0.026; t(26) = -2.56; p < 0.017]. With the applied cutoff of 30% pain reduction within the stimulation period, both the active and sham groups had 36% responders (n = 4) (Fisher's exact test, p = 1.00). In both groups (active stimulation and sham group), a significant decrease in the intensity of pain, somatic symptoms and an improvement in sleep quality over the study period was observed. Subjects reported no adverse events during the study. Conclusion: Although CES is an easily applicable and safe therapeutic option for chronic facial pain, active stimulation was not superior to sham stimulation. Among other reasons, this could be due to the short double-blinded treatment period, duration of the daily stimulation session or the small sample size.

Reduction of Edema and Pain in Transcutaneous Electrical Nerve Stimulation Treated-Arthritic Rat.

Transcutaneous electrical nerve stimulation (TENS) has been used to reduce pain or improve motor function in musculoskeletal and neurological disorders in the clinic. Although some studies have suggested electrotherapy as an intervention for edema, the effects and mechanisms of TENS on inflammation-induced edema remain unclear. Thus, we aimed to investigate the effects of TENS on arthritic pain with edema. 1% carrageenan was injected into the right tibiofemoral joint of 69 male Sprague-Dawley rats (200-250 g). After the development of arthritic pain, low-frequency (4-Hz, Low-TENS, n = 25) and high-frequency (100-Hz, High-TENS, n = 25) TENS with sub-motor threshold or placebo-TENS (n = 19) was applied for 20-min to medio-lateral part of the ipsilateral side. Weight bearing and knee-bend tests were used to assess pain-like behaviors. Also, we examined the size of edema and measured tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1ß) levels in the synovium by western blot. Eight rats in each of the two TENS groups were injected with Naloxone. Edema was reduced in the low- and high-frequency TENS groups at 6-h. TENS-treated rats showed reduced pain in the knee-bend test at 6-h. We observed decreased weight load shifts on the ipsilateral side in TENS groups. Naloxone reduced these effects. TNF-α and IL-1ß expression decreased in the synovial membrane at 6-h. These results suggest that low- and high-frequency TENS have acutely positive effects on inflammatory edema, with the management of arthritic pain and reduction in pro-inflammatory mediators. Therefore, Low-TENS and High-TENS may be useful in treating acute inflammatory pain and edema.

Comparing the effect of transcutaneous electrical nerve stimulation and massage therapy on post laparoscopic shoulder pain: a randomized clinical trial.

BACKGROUND: Shoulder pain is a common clinical problem after laparoscopic surgeries. The use of non-pharmacological massage and transcutaneous electrical nerve stimulation (TENS) as an adjunct to routine treatment is increasing to provide optimal pain relief. Therefore, we aimed to determine the effect of TENS and massage therapy on post laparoscopic shoulder pain (PLSP). METHODS: This study was conducted on 138 patients who underwent laparoscopic cholecystectomy. Patients were randomly divided into three groups: massage plus conventional pharmacological treatment (n = 46), TENS plus conventional pharmacological treatment (n = 46), and conventional pharmacological treatment (n = 46). Massage and TENS were performed three consecutive times after the patients regained consciousness in the inpatient wards. The intensity of Shoulder pain was evaluated using a visual analog scale before and 20 min after each treatment. RESULTS: Both massage therapy and TENS led to a significant reduction in the intensity of PLPS compared to the control group in all three measured times (p < 0.001). However, no significant difference was observed between TENS and massage at any of the three-time points. CONCLUSIONS: This study's findings demonstrated that massage and TENS techniques could reduce PLSP. TRIAL REGISTRATION: Registered in the Iranian registry of clinical trials ( www.irct.ir ) in 05/02/2022 with the following code: IRCT20200206046395N1.

Use and Effectiveness of Electrosuit in Neurological Disorders: A Systematic Review with Clinical Implications.

Electrical stimulation through surface electrodes is a non-invasive therapeutic technique used to improve voluntary motor control and reduce pain and spasticity in patients with central nervous system injuries. The Exopulse Mollii Suit (EMS) is a non-invasive full-body suit with integrated electrodes designed for self-administered electrical stimulation to reduce spasticity and promote flexibility. The EMS has been evaluated in several clinical trials with positive findings, indicating its potential in rehabilitation. This review investigates the effectiveness of the EMS for rehabilitation and its acceptability by patients. The literature was collected through several databases following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Positive effects of the garment on improving motor functions and reducing spasticity have been shown to be related to the duration of the administration period and to the dosage of the treatment, which, in turn, depend on the individual's condition and the treatment goals. Moreover, patients reported wellbeing during stimulation and a muscle-relaxing effect on the affected limb. Although additional research is required to determine the efficacy of this device, the reviewed literature highlights the EMS potential to improve the motor capabilities of neurological patients in clinical practice.

The effect of TENS on sleep: A pilot study.

BACKGROUND: Insomnia is the second most common neuropsychiatric disorder, but the current treatments are not very effective. There is therefore an urgent need to develop better treatments. Transcutaneous electrical nerve stimulation (TENS) may be a promising means of treating insomnia. OBJECTIVE: This work aims to explore whether and how TENS modulate sleep and the effect of stimulation waveforms on sleep. METHODS: Forty-five healthy subjects participated in this study. Electroencephalography (EEG) data were recorded before and after four mode low-frequency (1 Hz) TENS with different waveforms, which were formed by superimposing sine waves of different high frequencies (60-210 Hz) and low frequencies (1-6 Hz). The four waveform modes are formed by combining sine waves of varying frequencies. Mode 1 (M1) consists of a combination of high frequencies (60-110 Hz) and low frequencies (1-6 Hz). Mode 2 (M2) is made up of high frequencies (60-210 Hz) and low frequencies (1-6 Hz). Mode 3 (M3) consists of high frequencies (110-160 Hz) and low frequencies (1-6 Hz), while mode 4 (M4) is composed of high frequencies (160-210 Hz) and low frequencies (1-6 Hz). For M1, M3 and M4, the high frequency portions of the stimulus waveforms account for 50%, while for M2, the high frequency portion of the waveform accounts for 65%. For each mode, the current intensities ranged from 4 mA to 7 mA, with values for each participant adjusted according to individual tolerance. During stimulation, the subjects were stimulated at the greater occipital nerve by the four mode TENS. RESULTS: M1, M3, and M4 slowed down the frequency of neural activity, broadened the distribution of theta waves, and caused a decrease in activity in wakefulness-related regions and an increase in activity in sleep-related regions. However, M2 has the opposite modulation effect. CONCLUSION: These results indicated that low-frequency TENS (1 Hz) may facilitate sleep in a waveform-specific manner. Our findings provide new insights into the mechanisms of sleep modulation by TENS and the design of effective insomnia treatments.

The effects of neuromuscular electrical stimulation to the ankle pronators on neural excitability & functional status in patients with chronic ankle instability.

OBJECTIVES: Chronic ankle instability (CAI) is associated with decreased neural excitability that negatively impacts function. This study assessed a 2-week neuromuscular electrical stimulation (NMES) or transcutaneous electrical nerve stimulation (TENS) intervention over the ankle pronators on neural excitability, performance, and patient-reported function in patients with CAI. STUDY DESIGN: Randomized controlled trial. PARTICIPANTS: Twenty participants with CAI completed the study. MAIN OUTCOME MEASURES: Participants were assessed for reflexive and corticospinal excitability to the ankle muscles, dynamic balance, side-hop test performance and patient-reported outcomes at baseline, post-intervention (2-weeks), and retention (4-weeks). Between baseline and post-intervention, participants reported for 5 sessions where they received either sub-noxious NMES (n = 11) or sensory-level TENS (n = 9) over the ankle pronators. RESULTS: Improved reflexive excitability to the ankle pronators was observed in TENS at post-intervention (p = 0.030) and retention (p = 0.029). Cortical excitability to the dorsiflexors increased in TENS at post-intervention (p = 0.017), but not at retention (p = 0.511). No significant changes were found for other neural measures, balance ability, hopping, or patient-reported function (p > 0.050). CONCLUSIONS: Our results suggest TENS modified neural excitability; however, these changes were not enough to impact clinical function. While TENS may be capable of neuromodulation, it may require rehabilitative exercise to generate lasting changes. NCT04322409. LEVEL OF EVIDENCE: Level 2.

Transcutaneous electrical nerve stimulation over acupoint for chronic obstructive pulmonary disease: A systematic review and meta-analysis.

Background: Transcutaneous electrical nerve stimulation over an acupoint (acu-TENS), a new technique applied in pulmonary rehabilitation programs, has been gradually used in the management of chronic obstructive pulmonary disease (COPD). However, the effects of acu-TENS have not been fully evaluated. Therefore, this review was conducted to assess the effects of acu-TENS on COPD. Methods: A total of seven electronic databases were searched from their inception to September 2021 for randomized controlled trials of acu-TENS for COPD. Two investigators independently performed data extraction and methodological quality assessment. Heterogeneity was examined by Cochrane χ2 and I 2 tests. The source of heterogeneity was investigated by subgroup analysis or sensitivity analysis. Results: In our review, ten studies between 2008 and 2021 were included. The aggregated results indicated that acu-TENS showed positive effects in forced expiratory volume in 1 s (FEV1) [MD = 0.13 L, 95% CI (0.11-0.16), P < 0.00001], FEV1% predicted [MD = 5.92%, 95% CI (3.43-8.41), P < 0.00001], 6-min walk distance (6MWD) [MD = 14.68m, 95% CI (6.92-22.44), P = 0.0002], dyspnea visual analog scale (DVAS) [MD = -7.58, 95%CI (-14.33 to -0.84), P = 0.03], modified Borg scale (MBS) [MD = -0.46, 95% CI (-0.86 to -0.06), P = 0.03], and COPD assessment test (CAT) [MD = -4.25, 95% CI (-5.24 to -3.27), P < 0.00001]. Although six studies reported adverse effects, only one patient had shoulder pain after acu-TENS. Conclusion: Acu-TENS seems to be effective in improving pulmonary function and health status in patients with COPD, with little effect on exercise capacity and dyspnea. However, this result should be interpreted with caution, and high-quality RCTs were needed for further verification.

Comparison of the effective intensity of transcutaneous electrical nerve stimulation contralateral to a pain site for analgesia.

[Purpose] This study aimed to compare the effectiveness of transcutaneous electrical nerve stimulation contralateral to the pain site for analgesia to identify the effective stimulation intensity. [Participants and Methods] Ten healthy adult females were recruited for the study. The same heat stimulation was applied to the left wrist joint of each participant to induce pain, serving as the control. Transcutaneous electrical nerve stimulation was then randomly administered to the right wrist, corresponding to the same dermatome contralateral to the painful site, at the intensities of comfortable stimulation, pain threshold, and maximum pain. The effect of transcutaneous electrical nerve stimulation was assessed using a Visual Analogue Scale and by analysis of heart rate variability. [Results] The Visual Analogue Scale score was significantly lower after stimulation with the maximum pain intensity than that for control, and there were no significant differences among the intensities of comfortable stimulation, pain threshold, and maximum pain. No significant differences were found among the groups in terms of high and low-to-high frequency components. [Conclusion] Transcutaneous electrical nerve stimulation at the maximum pain intensity to the dermatome area contralateral to that of the dorsal pain site of the left wrist was considered effective.

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.

Evaluating hip disarticulation outcomes in a 51-patient series.

Background: Hip disarticulations are proximal lower extremity amputations with high postoperative complication and mortality rates. The purpose of the study was to evaluate hip disarticulation outcomes at our institution. Targeted Muscle Reinnervation (TMR) is an effective surgical technique shown to reduce pain in amputees. A secondary goal of the study was to evaluate the impact of implementing TMR on this patient population. Methods: A retrospective review was performed for patients who underwent hip disarticulation with and without TMR between 2009 and 2020. Information on one-year mortality, thirty-day complication rates, operation times, surgical charges, and pain scores was collected. Results: Fifty-one patients underwent hip disarticulation, eight of which had TMR performed at the time of their hip disarticulation. The one-year mortality rate was 37% with 30-day infection, readmission, reoperation, and rates of 37%, 39%, and 27% respectively. The thirty-day major complication rate was 47% overall but not statistically significantly different between groups. There were no differences between groups with regard to 30-day readmission, reoperation, and infection rates. Conclusions: Our results represent one of the largest series of hip disarticulation outcomes. Performing TMR at the time of hip disarticulation did not negatively affect outcomes and may be a beneficial adjunct to improve pain. Further research is warranted.

Identifying oscillations under multi-site sensory stimulation for high-level peripheral nerve injured patients: a pilot study.

Objective.For high-level peripheral nerve injuryed (PNI) patients with severe sensory dysfunction of upper extremities, identifying the multi-site tactile stimulation is of great importance to provide neurorehabilitation with sensory feedback. In this pilot study, we showed the feasibility of identifying multi-site and multi-intensity tactile stimulation in terms of electroencephalography (EEG).Approach.Three high-level PNI patients and eight non-PNI participants were recruited in this study. Four different sites over the upper arm, forearm, thumb finger and little finger were randomly stimulated at two intensities (both sensory-level) based on the transcutaneous electrical nerve stimulation. Meanwhile, 64-channel EEG signals were recorded during the passive tactile sense stimulation on each side.Main results.The spatial-spectral distribution of brain oscillations underlying multi-site sensory stimulation showed dominant power attenuation over the somatosensory and prefrontal cortices in both alpha-band (8-12 Hz) and beta-band (13-30 Hz). But there was no significant difference among different stimulation sites in terms of the averaged power spectral density over the region of interest. By further identifying different stimulation sites using temporal-spectral features, we found the classification accuracies were all above 89% for the affected arm of PNI patients, comparable to that from their intact side and that from the non-PNI group. When the stimulation site-intensity combinations were treated as eight separate classes, the classification accuracies were ranging from 88.89% to 99.30% for the affected side of PNI subjects, similar to that from their non-affected side and that from the non-PNI group. Other performance metrics, including specificity, precision, and F1-score, also showed a sound identification performance for both PNI patients and non-PNI subjects.Significance.These results suggest that reliable brain oscillations could be evoked and identified well, even though induced tactile sense could not be discerned by the PNI patients. This study have implication for facilitating bidirectional neurorehabilitation systems with sensory feedback.

Transcutaneous Electrical Nerve Stimulation (TENS) for the Treatment of Renal Colic in the ED: A Randomized, Double-Blind, Placebo-Controlled Trial.

STUDY OBJECTIVE: To determine the analgesic efficacy of TENS treatment in patients with renal colic in the emergency department (ED). METHODS: This double-blind, randomized controlled trial was conducted in a tertiary care ED. Patients with a definitive diagnosis of renal colic were assigned (1:1) as randomized to receive the real TENS with frequency 100 Hz, pulse width 200 microseconds, voltage 2 mA, or placebo with sham TENS. Pain intensity was measured using visual analog scales (VAS) at baseline, after 15 and 30th minutes. RESULTS: A total of 100 patients were included in the final analysis: 50 patients treated with real TENS and 50 patients treated with sham TENS. VAS scores in both groups were similar at baseline. The mean reduction in VAS score at 15 min was 33.3 ± 17.6 (95% Confidence interval (CI): 28.3 to 38.3) for the real TENS group and 14.9 ± 11.6 (95% CI 11.6 to 18.2) for the sham TENS group (mean difference: 18.4 (95% CI: 12.5 to 24.4, P < 0.0001). The mean reduction in VAS score at 30 min was 63.7 ± 21.1 (95% CI: 57.7 to 69.7) for the real TENS group and 14.9 ± 16.2 (95% CI: 19.5 to 10.3) for the sham TENS group (mean difference: 48.8, 95% CI: 41.4 to 56.3, P < 0.0001). Four patients (8%) in the real TENS group and 24 patients (48%) in the sham TENS group required the rescue medication after 30th minutes. CONCLUSIONS: TENS is effective for acute pain treatment in renal colic patients in the ED. TENS therapy could be a treatment option for renal colic.

Evaluation of multiple perceptual qualities of transcutaneous electrical nerve stimulation for evoked tactile sensation in forearm amputees.

Objective. Evoked tactile sensation (ETS) elicited by transcutaneous electrical nerve stimulation (TENS) is promising to convey digit-specific sensory information to amputees naturally and non-invasively. Fitting ETS-based sensory feedback to amputees entails customizing coding of multiple sensory information for each stimulation site. This study was to elucidate the consistency of percepts and qualities by TENS at multiple stimulation sites in amputees retaining ETS.Approach. Five transradial amputees with ETS and fourteen able-bodied subjects participated in this study. Surface electrodes with small size (10 mm in diameter) were adopted to fit the restricted projected finger map on the forearm stump of amputees. Effects of stimulus frequency on sensory types were assessed, and the map of perceptual threshold for each sensation was characterized. Sensitivity for vibration and buzz sensations was measured using distinguishable difference in stimulus pulse width. Rapid assessments for modulation ranges of pulse width at fixed amplitude and frequency were developed for coding sensory information. Buzz sensation was demonstrated for location discrimination relating to prosthetic fingers.Main results. Vibration and buzz sensations were consistently evoked at 20 Hz and 50 Hz as dominant sensation types in all amputees and able-bodied subjects. Perceptual thresholds of different sensations followed a similar strength-duration curve relating stimulus amplitude to pulse width. The averaged distinguishable difference in pulse width was 12.84 ± 7.23µs for vibration and 15.21 ± 6.47µs for buzz in able-bodied subjects, and 14.91 ± 10.54µs for vibration and 11.30 ± 3.42µs for buzz in amputees. Buzz coding strategy enabled five amputees to discriminate contact of individual fingers with an overall accuracy of 77.85%.Significance. The consistency in perceptual qualities of dominant sensations can be exploited for coding multi-modality sensory feedback. A fast protocol of sensory coding is possible for fitting ETS-based, non-invasive sensory feedback to amputees.

Nonsurgical Approaches to Neuroma Management.

Symptomatic neuromas and chronic neuropathic pain are significant problems affecting patients' quality of life and independence that are challenging to treat. These symptoms are due to structural and functional changes that occur peripherally within neuromas, as well as alterations that occur centrally within the brain and spinal cord. A multimodal approach is most effective, with goals to minimize opioid use, to capitalize on the synergistic effects of nonopioid medications and to explore potential benefits of novel adjunctive treatments.

Transcutaneous electrical nerve stimulation (TENS): towards the development of a clinic-friendly method for the evaluation of excitatory and inhibitory pain mechanisms.

Background: Temporal summation and conditioned pain modulation (CPM) can be measured using a thermode and cold pressor test (CPTest). Unfortunately, these complex and expensive tools are ill-suited for routine clinical assessments. Aims: We aimed to compare the temporal summation and CPM obtained with the thermode + CPTest paradigm to those obtained with a novel paradigm using transcutaneous electrical nerve stimulation (TENS). Methods: We assessed temporal summation and CPM in 29 healthy participants, using two paradigms (random order): TENS, and thermode + CPTest. In the TENS paradigm, both the conditioning stimulus (CS) and the test stimulus (TS) were delivered using TENS; in the thermode + CPTest paradigm, the CS consisted of a CPTest and the TS was delivered using a thermode. We compared the average temporal summation and CPM evoked by the two paradigms. Results: Average temporal summation was similar for both modalities (P = 0.90), and the number of participants showing temporal summation was similar in both paradigms (19 with thermode vs. 18 with TENS; P = 1.00). Average CPM response was larger following the thermode + CPTest than following the TENS (P = 0.005), and more participants showed CPM with the thermode + CPTest paradigm compared to the TENS paradigm (24 vs. 14; P = 0.01). Conclusions: Both paradigms were roughly equivalent in the ability to evoke temporal summation (although response to one modality did not predict response to the other), but the TENS paradigm appeared to be less apt to induce a CPM response than the thermode + CPTest paradigm.

Contexte: La sommation temporelle et la modulation de la douleur conditionnée (MDC) peuvent être mesurées à l'aide d'une thermode et d'un test au froid. Malheureusement, ces tests complexes et coûteux sont mal adaptés aux évaluations cliniques de routine.Objectifs: Nous avons cherché à comparer la sommation temporelle et la modulation de la douleur conditionnée obtenues avec le paradigme thermode + test au froid à ceux obtenus avec un nouveau paradigme utilisant la neurostimulation électrique transcutanée (TENS).Méthodes: Nous avons évalué la sommation temporelle et la modulation de la douleur conditionnée chez 29 participants en bonne santé, en utilisant les deux paradigmes (ordre aléatoire) : TENS, et thermode + test au froid. Dans le paradigme TENS, Le stimulus de conditionnement et le stimulus d'essai ont été transmis à l'aide de la neurostimulation électrique transcutanée ; dans le paradigme thermode + test au froid, le stimulus de conditionnement consistait en un test au froid et le stimulus d'essai était transmis à l'aide d'une thermode. Nous avons comparé la sommation temporelle et la modulation de la douleur conditionnée moyennes évoqués par les deux paradigmes.Résultats: La sommation temporelle moyenne était similaire pour les deux modalités (P = 0,90), et le nombre de participants ayant montré une sommation temporelle étaient similaires dans les deux paradigmes (19 avec la thermode contre 18 avec la TENS; P = 1,00). La réponse moyenne de modulation de la douleur conditionnée était plus importante après la thermode + test au froid qu'après la neurostimulation électrique transcutanée (P = 0,005), et un plus grand nombre de participants ont montré une modulation de la douleur conditionnée avec la thermode + test au froid par rapport au paradigme TENS (24 contre 14 ; P = 0,01).Conclusions: Les deux paradigmes sont à peu près équivalents en ce qui concerne la capacité d'évoquer la sommation temporelle (bien que la réaction à une modalité ne prévoie pas la réaction à l'autre), mais le paradigme TENS semble moins apte à induire une réponse de modulation de la douleur conditionnée que le paradigme thermode + test au froid.

Analgesic efficacy of a portable, disposable, and self-applied transcutaneous electrical nerve stimulation device during migraine attacks: A real-life randomized controlled trial.

OBJECTIVE: The objective of this study was to evaluate the analgesic efficacy of a portable, disposable, and home self-applied transcutaneous electrical nerve stimulation (TENS) device during migraine attacks. BACKGROUND: TENS has been used as a noninvasive treatment for migraine, but there are no reports on the outcomes following use of this treatment option for use at home during migraine attacks. DESIGN AND METHODS: A double-blind, randomized controlled trial was conducted over 3 months, with monthly assessments. Active placebos (sham group) were in place and were allocated at a 1:1 ratio. Adult patients who had been diagnosed with migraine by a specialist were included. Pain intensity levels and functional disability were measured before and after the 20-min self-applied TENS intervention during the migraine attacks. RESULTS: Seventy-four participants were randomly allocated to the sham and intervention groups. Although both groups of subjects reported lower pain scores, the intervention group showed a statistically significant reduction in pain scores compared to the sham group. CONCLUSION: In our controlled trial, the use of a self-applied, TENS device is safe and effective in relieving pain associated with migraine attacks. Participants in the intervention group showed a statistically significant improvement in pain and functional disability scores. TENS has been used as a noninvasive treatment for migraine, but there are no reports on the outcomes following use of this treatment option for use at home during migraine attacks. This double-blind, randomized controlled trial had 2 groups: active-placebo and intervention. Seventy-four participants were randomly allocated. Participants in the intervention group showed a statistically significant improvement in pain and functional disability scores.

Resolving Long-Standing Uncertainty about the Clinical Efficacy of Transcutaneous Electrical Nerve Stimulation (TENS) to Relieve Pain: A Comprehensive Review of Factors Influencing Outcome.

Pain is managed using a biopsychosocial approach and pharmacological and non-pharmacological treatments. Transcutaneous electrical nerve stimulation (TENS) is a technique whereby pulsed electrical currents are administered through the intact surface of the skin with the intention of alleviating pain, akin to 'electrically rubbing pain away'. Despite over 50 years of published research, uncertainty about the clinical efficacy of TENS remains. The purpose of this comprehensive review is to critically appraise clinical research on TENS to inform future strategies to resolve the 'efficacy-impasse'. The principles and practices of TENS are described to provide context for readers unfamiliar with TENS treatment. The findings of systematic reviews evaluating TENS are described from a historical perspective to provide context for a critical evaluation of factors influencing the outcomes of randomized controlled trials (RCTs); including sample populations, outcome measures, TENS techniques, and comparator interventions. Three possibilities are offered to resolve the impasse. Firstly, to conduct large multi-centered RCTs using an enriched enrolment with randomized withdrawal design, that incorporates a 'run-in phase' to screen for potential TENS responders and to optimise TENS treatment according to individual need. Secondly, to meta-analyze published RCT data, irrespective of type of pain, to determine whether TENS reduces the intensity of pain during stimulation, and to include a detailed assessment of levels of certainty and precision. Thirdly, to concede that it may be impossible to determine efficacy due to insurmountable methodological, logistical and financial challenges. The consequences to clinicians, policy makers and funders of this third scenario are discussed. I argue that patients will continue to use TENS irrespective of the views of clinicians, policy makers, funders or guideline panel recommendations, because TENS is readily available without prescription; TENS generates a pleasant sensory experience that is similar to easing pain using warming and cooling techniques; and technological developments such as smart wearable TENS devices will improve usability in the future. Thus, research is needed on how best to integrate TENS into existing pain management strategies by analyzing data of TENS usage by expert-patients in real-world settings.

Determination of Current Flow Induced by Transcutaneous Electrical Nerve Stimulation for the Treatment of Migraine: Potential for Optimization.

Introduction: Transcutaneous electrical nerve stimulation (TENS) for migraine involves the application of pulsatile stimulation through electrodes placed on the forehead to target the underlying trigeminal nerves. It is a simple, safe modality and has secured clinical approval in several markets including the European Union and the United States. Despite nearing almost 7 years of use (postclinical approval), the exact mechanism of action is not fully known. Guided by the need to stimulate the trigeminal nerves bilaterally, electrode dimensions are simply required to extend enough to cover the underlying nerves. The goal of this study is to examine induced current flow [magnitude and spatial distribution of electric field (EF)] and another driver of stimulation [activating function (AF)] due to TENS therapy for migraine for the first time. We further consider the effect of changing the electrode dimension and shape and propose a design modification to deliver optimal flow. Methods: We developed the first ultra-high-resolution finite element (FE) model of TENS for migraine incorporating the target supratrochlear (ST) and the supraorbital (SO) nerves. We first simulated the clinically approved V-shaped geometry. We then considered three additional designs: extended V-shaped, idealized pill-shaped, and finally an extended V-shaped but with greater contact spacing (extended V-shaped +CS). Results: Our findings revealed that the clinically approved electrode design delivered substantially higher mean current flow to the ST nerve in comparison with the SO nerves (Medial: 53% and Lateral: 194%). Consideration of an extended design (~10 mm longer and ~ 4 mm shorter) and a pill-like design had negligible impact on the induced current flow pattern. The extended V-shaped +CS montage delivered relatively comparable current flow to each of the three target nerves. The EF induced in the ST nerve was 49 and 141% higher in the Medial and Lateral SO nerve, respectively. When considering maximum induced values, the delivery of comparable stimulation was further apparent. Given the existing electrode design's established efficacy, our results imply that preferential targeting of the ST nerve is related to the mechanism of action. Additionally, if comparable targeting of all three nerves continues to hold promise, the extended V-shaped +CS montage presents an optimized configuration to explore in clinical studies.

Supraspinal neural mechanisms of the analgesic effect produced by transcutaneous electrical nerve stimulation.

Although the analgesic effects of conventional transcutaneous electrical nerve stimulation (TENS) and acupuncture-like TENS are evident, their respective neural mechanisms in humans remain controversial. To elucidate and compare the supraspinal neural mechanisms of the analgesic effects produced by conventional TENS (high frequency and low intensity) and acupuncture-like TENS (low frequency and high intensity), we employed a between-subject sham-controlled experimental design with conventional, acupuncture-like, and sham TENS in 60 healthy human volunteers. In addition to assessing the TENS-induced changes of subjective ratings of perceived pain, we examined the TENS associated brainstem activities (fractional amplitude of low frequency fluctuations, fALFF) and their corresponding resting state functional connectivity (RSFC) with higher-order brain areas using functional magnetic resonance imaging. The analgesic effect of conventional TENS was only detected in the forearm that received TENS, coupled with decreased pons activity and RSFC between pons and contralateral primary somatosensory cortex. In contrast, acupuncture-like TENS produced a spatially diffuse analgesic effect, coupled with increased activities in both subnucleus reticularis dorsalis (SRD) and rostral ventromedial medulla (RVM), and decreased RSFC between SRD and medial frontal regions as well as between SRD and lingual gyrus. To sum up, our data demonstrated that conventional TENS and acupuncture-like TENS have different analgesic effects, which are mediated by different supraspinal neural mechanisms.