Assessing the relevance of mental health factors in fibromyalgia severity: A data-driven case study using explainable AI.

BACKGROUND AND OBJECTIVE: Fibromyalgia is a chronic disease that causes pain and affects patients' quality of life. Current treatments focus on pharmacological therapies for pain reduction. However, patients' psychological well-being is also affected, with depression and pain catastrophizing being common. This research addresses the clinicians' need to assess the influence of mental health factors on FM severity compared to pain factors. METHODS: A co-development study between FM clinicians and data scientists analyzed data from 166 FM-diagnosed patients to assess the influence of mental health factors on FM severity in comparison to pain factors. The study used the Polysymptomatic Distress Scale (PDS) and Fibromyalgia Impact Questionnaire (FIQ) as FM severity indicators and collected 15 variables including regarding demographics, pain intensity perceived, and mental health factors. The team used an author's developed framework to identify the optimal FM severity classifier and explainability by selecting a number of features that lead to obtaining the best classification result. Machine learning classifiers employed in the framework were: decision trees, logistic regression, support vector machines, random forests, AdaBoost, extra trees, and RUSBoost. Explainability analyses were conducted using the following explainable AI techniques: SHapley Additive exPlanations (SHAP), Partial Dependence Plot (PDP), and Mean Decrease Impurity (MDI). RESULTS: A balanced random forest with 6 features achieved the best performance with PDS (AUC_ROC, mean = 0.81, std = 0.07). Being FIQ the target variable, due to the imbalance in FM severity levels, a binary and a multiclass classification approaches were considered achieving the optimal performance, respectively, a logistic regression classifier (AUC_ROC, mean = 0.83, std = 0.08) with 6 selected features, and a random forest (AUC_ROC, mean = 0.91, std = 0.04) with 8 selected features. Next, the explainability analysis determined mental health factors were found to be more relevant than pain perceived factors for FM severity. CONCLUSIONS: This study's findings, validated by clinicians, are potentially aligned with FM international guidelines that promote non-pharmacological interventions such as promoting mental well-being of FM patients.

The effect of therapeutic exercise in the prevention of lymphoedema secondary to breast cancer: a systematic review.

Introduction: One of the most frequent complications of breast cancer treatment is lymphoedema (LE), with lymphadenectomy and radiotherapy being the main triggers of this pathology in developed countries. The aim of the study was to determine the efficacy of therapeutic exercise in the prevention of upper limb (UL) lymphoedema evaluated through cirtometry, volumetry, or bioimpedance spectroscopy (BIS) in women after breast cancer removal surgery. Material and methods: The Pubmed, PEDro, and Cochrane databases were consulted up to May 2020, including randomised clinical trials (RCTs) on therapeutic physical exercise as a possible preventive measure against breast cancer-related lymphoedema (BCRL). The studies were requested to have participants with UL lymphoedema and a control group. Results: A total of 304 articles were found, of which 9 were included (stand-alone studies). A therapeutic exercise program (strength and/or aerobic training) in women who had been surgically intervened for breast cancer may prevent lymphedema, compared to a regular care. Conclusions: A therapeutic exercise program (strength and/or aerobic training) in women operated on for breast cancer contributes to reducing the number of cases that could obtain a greater difference in volume in their upper limbs, compared to a regular care program. However, further research is necessary to affirm that therapeutic physical exercise prevents BCRL.

Effectiveness of Transcranial Direct Current Stimulation Combined With Exercising in People With Fibromyalgia: A Randomized Sham-Controlled Clinical Trial.

OBJECTIVE: To evaluate the effectiveness of transcranial direct current stimulation (tDCS) combined with exercising in people with fibromyalgia. DESIGN: Randomized, triple-blind, sham-controlled, clinical trial. SETTING: Primary health care center. PARTICIPANTS: A total of 120 volunteer participants (N=120) between 18 and 65 years old and diagnosed with fibromyalgia. Four participants dropped out of the study for causes unrelated to the intervention. INTERVENTION: Participants were randomized into 3 groups (active tDCS+exercising, sham tDCS+exercising, no-intervention control). The intervention was delivered in 5 sessions over 2 weeks. MAIN OUTCOME MEASURES: Pain intensity and referred pain area after suprathreshold pressure stimulation. RESULTS: Pain intensity further decreased in the active tDCS group vs control (mean, -14.43; 95% confidence interval, -25.27 to -3.58) at post intervention, unlike the sham tDCS group. Both tDCS groups did not achieve greater reductions in referred pain vs control. In the active tDCS group, health status (mean, -14.80; 95% confidence interval, -23.10 to -6.50) and pain catastrophizing (mean, -6.68, 95% confidence interval, -11.62 to -1.73) improved at post intervention, and so did health status (mean, -8.81; 95% confidence interval, -17.11 to -0.51), pain catastrophizing (mean, -7.00; 95% confidence interval, -12.13 to -1.87), and depression (mean, -3.52; 95% confidence interval, -6.86 to -0.19) after 1 month. In the sham tDCS group, improvements were recorded in health status (mean, -13.21; 95% confidence interval, -21.52 to -4.91) and depression (mean, -3.35; 95% confidence interval, -6.35 to -0.35) at post intervention and in health status (mean, -8.77; 95% confidence interval, -17.06 to -0.47), pain catastrophizing (mean, -5.68; 95% confidence interval, -10.80 to -0.55), and depression (mean, -3.98; 95% confidence interval, -7.31 to -0.64) after 1 month. No intergroup differences were observed between active and sham tDCS. CONCLUSIONS: Active and sham tDCS improved health status, pain catastrophizing, and depression vs control, but pain intensity decreased only in the active tDCS group.

Effects of dry needling on function, hypertonia and quality of life in chronic stroke: a randomized clinical trial.

BACKGROUND: Persons with stroke commonly have impairments associated with a reduction in functionality. Motor impairments are the most prevalent, causing an impact on activities of daily life. OBJECTIVE: The aim of this study was to evaluate the effect of a session of dry needling (DN) applied to the upper extremity muscles on the sensorimotor function, hypertonia, and quality of life of persons with chronic stroke. METHODS: A randomized, sham-controlled clinical trial was performed. Participants were randomly assigned into an intervention group that received a single session DN in the biceps brachii, brachialis, flexor digitorum superficialis and profundus, extensor digitorum, adductor pollicis and triceps brachii muscles, or into a control group that received the same treatment but with a sham DN intervention. Treatment outcomes included the Fugl-Meyer Assessment Scale for the upper extremity, the Modified Modified Ashworth Scale, and the EuroQol-5D questionnaire. Measurements were carried out before, immediately after, and 14 days after intervention. RESULTS: Twenty-three persons participated in the study. Significant differences between groups were observed after the intervention in the total wrist-hand motor score (p = 0.023) and sensorimotor score (p = 0.022), for hypertonia in the elbow extensors both after treatment (p = 0.002) and at follow-up (p = 0.018), and in quality of life at follow-up (p = 0.030). CONCLUSIONS: A single session of DN improved total wrist-hand motor function and total sensorimotor function in persons with chronic stroke immediately after treatment, as well as quality of life 2 weeks after treatment. TRIAL REGISTRATION NUMBER: NCT03546517 (ClinicalTrials.gov).

The effect of dry needling of myofascial trigger points on muscle stiffness and motoneuron excitability in healthy subjects.

BACKGROUND: Myofascial trigger points (MTrPs) are hypersensitive nodules in a taut band (TB) of skeletal muscle. Dry needling (DN) is an invasive technique recommended for the treatment of MTrPs. However, to our knowledge, no studies have investigated the influence of the DN technique on modification of muscle stiffness and neurophysiological properties of MTrPs. OBJECTIVE: The objective was to examine the effect of DN on muscle stiffness and motoneuron excitability of a latent medial MTrP (nodule and TB) of the soleus muscle in non-injured subjects. METHODS: A double-blinded randomised controlled trial of 46 subjects with latent medial MTrPs of the soleus was conducted, in which all received one session of DN. The intervention group (n = 23) were subjected to DN into the MTrP (the nodule), while the control group (n = 23) were subjected to DN into the TB. Assessment was carried out at baseline (pre-test), after the intervention (post-test) and 1 week after the intervention (follow-up). Biomechanical variables (muscle resistive force at 10°/s and 180°/s, muscle extensibility and strength), as measured with an isokinetic dynamometer, and neurophysiological variables (H-reflex), were recorded. RESULTS: There were no statistically significant differences in biomechanical or neurophysiological assessments between groups. Considering the intra-group analysis, subjects in the intervention group exhibited increased maximal isometric voluntary force to ankle plantarflexion (MIVFp) at both post-intervention and follow-up assessment (p < 0.0125; 0.2 < d < 0.5), while no changes were found in the control group. CONCLUSION: One session of DN targeting latent MTrPs did not change muscle stiffness, muscle extensibility or motoneuron excitability. Further research on subjects with muscle tone disorders should be considered to better address the impact of DN on muscle tone. TRIAL REGISTRATION NUMBER: NCT02575586 (ClinicalTrials.gov).

Effects of dry needling on gait and muscle tone in Parkinson's disease: a randomized clinical trial.

BACKGROUND: Alterations in gait and muscular rigidity are common and disabling in persons with Parkinson's disease (PD). OBJECTIVE: The aim of this study was to determine whether a single dry needling (DN) session can promote changes in gait and muscle tone in the lower extremities as well as in the evolution of the disease in persons with PD. METHODS: A randomized double-blind clinical trial was designed. Participants were randomly assigned to an intervention group (IG) that received a session of DN over the semitendinosus, medial gastrocnemius, soleus and rectus femoris muscles, or to a control group (CG) that received a session of sham DN in the same muscles. The effects of DN were assessed using the timed up and go test (TUG), 10 meter walk test (10MWT), 6 minute walk test (6MWT) and myotonometry before, immediately after, and 7 days after the intervention. RESULTS: Thirty-three participants were analyzed aged 69.9 ± 7.2 years (mean ± SD; 39% female). There were no significant differences between the IG and CG for any outcomes. Significant differences were observed when comparing the Pre and Follow-up values in the IG for functional mobility of gait in the TUG (p = 0.049), gait speed in the 10MWT (p = 0.041) and muscle tone in the lower extremities by myotonometry (frequency (p = 0.027) and stiffness (p = 0.013)). By comparison, there were no significant within-group differences in the CG. CONCLUSION: A single session of DN had no measurable benefit compared to a single session of sham DN. Within-group changes in the IG suggested improvements in functional mobility of gait and gait speed, as well as changes in the muscle tone in the lower extremities of PD patients, which could be worthy of further exploration by future research.

A New Approach to Assess Blinding for Transcranial Direct Current Stimulation Treatment in Patients with Fibromyalgia. A Randomized Clinical Trial.

Correct blinding is essential for preventing potential biases. The aim of this study was to assess the blinding of participants and a therapist following treatment with transcranial direct current stimulation in subjects with fibromyalgia using James' and Bang's blinding indexes. Eighty subjects were randomly allocated either active or sham stimulation groups in an intervention of five sessions lasting 20 min each. A questionnaire was delivered to both the therapist and patients after the last session to record their guess of which treatment had been applied. No differences between the groups were noted at baseline in terms of demographic or clinical data. James' BI was 0.83 (CI 95%: 0.76-0.90) for the patients and 0.55 (CI 95%: 0.45-0.64) for the therapist. Bang's BI for subjects was -0.08 (CI 95%: -0.24-0.09) and -0.8 (CI 95%: -0.26-0.1) for the active and sham transcranial direct current stimulation groups, respectively. Bang's BI for the therapist was 0.21 (CI 95%: -0.02-0.43) and 0.13 (CI 95%: -0.09-0.35) for the active and sham transcranial direct current stimulation groups, respectively. Protocols of active and sham transcranial direct current stimulation applied in this study have shown satisfactory blinding of the therapist and subjects with fibromyalgia.

Effects of Dry Needling on Biomechanical Properties of the Myofascial Trigger Points Measured by Myotonometry: A Randomized Controlled Trial.

OBJECTIVE: The purpose of the present study was to examine the effect of dry needling (DN) on the biomechanical properties of a latent medial myofascial trigger point (MTrP) of the soleus muscle compared with an adjacent point within the taut band (TB) measured by myotonometry. METHODS: Fifty asymptomatic volunteers were randomly assigned to an intervention group (n = 26) or control group (n = 24). One session of DN was performed in every group as follows: 10 needle insertions into the MTrP area (intervention group) or TB area (control group). Myotonometric measurements (frequency, decrement, and stiffness) were performed at baseline (pre-intervention) and after the intervention (post-intervention) in both locations (MTrP and TB areas). RESULTS: The results showed that stiffness outcome significantly decreased with a large effect size after DN in the MTrP when measured in the MTrP location (P = .002; d = 0.928) but not when measured in the TB location. In contrast, no significant changes were observed in any location when the TB was needled (P > .05). CONCLUSIONS: The findings suggest that only DN into the MTrP area was effective in decreasing stiffness outcome, therefore a specific puncture was needed to modify myofascial muscle stiffness.

Efficacy of the use of unaffected hand containment in unimanual intensive therapy to increase visuomotor coordination in children with hemiplegia: a randomized controlled pilot study.

BACKGROUND: The capacity of children with hemiplegia to be engaged in anticipatory action planning is affected. There is no balance among spatial, proprioceptive and visual information, thus altering the affected upper limb visuomotor coordination. The objective of the present study was to assess the improvement in visuomotor coordination after the application of a unimanual intensive therapy program, with the use of unaffected hand containment compared with not using unaffected hand containment. METHODS: A simple blind randomized clinical trial was realized. A total of 16 subjects with congenital infantile hemiplegia participated in the study with an age mean of 5.54 years old (SD:1.55). Two intensive protocols for 5 weeks of modified constraint-induced movement therapy (mCIMT) or unimanual therapy without containment (UTWC) were executed 5 days per week (2 h/day). Affected upper limb visuomotor coordination (reaction time, task total time, active range, dynamic grasp) was measured before-after intensive therapy using a specific circuit with different slopes (10°/15°). RESULTS: Statistically significant inter-group differences were found after the intervention, with clinically relevant results for the mCIMT group not seen in UTWC, in the following variables: reaction time 10°slope (p = 0.003, d = 2.44), reaction time 15°slope (p = 0.002, d = 2.15) as well as for the task total time 10°slope (p = 0.002, d = 2.25), active reach 10°slope (p = 0.002, d = 2.7), active reach 15°slope (p = 0.003, d = 2.29) and dynamic grasp 10°/15°slopes (p = <0.001, d = 2.69). There were not statistically significant inter-group differences in the total task time with 15°slope (p = 0.074, d = 1.27). CONCLUSIONS: The use of unaffected hand containment in mCIMT would allow improvements in the affected upper limb's visuomotor coordination. Thus, it would favor clinical practice to make decisions on therapeutic approaches to increase the affected upper limb functionality and action planning in children diagnosed with infantile hemiplegia (4-8 years old).

Effectiveness of dry needling for upper extremity spasticity, quality of life and function in subacute phase stroke patients.

BACKGROUND: Stroke is the fourth leading cause of death in Europe, represents one of the most common causes of disability in adult patients, and involves considerable short- and long-term social and healthcare costs. The effectiveness of deep dry needling (DDN) on affected arm functionality was assessed throughout 8 weeks of treatment in patients with stroke in the subacute phase. METHODS: Eighty patients were included in this two-group non-randomised study after a propensity score analysis was carried out. Both groups received standard physiotherapy treatment on the affected arm. The needling group also received six sessions of DDN during the 8-week period. Patients were evaluated before and after each session using the Fugl-Meyer upper extremity (FM UE) scale, the modified modified Ashworth scale (MMAS), the resistance to passive movement scale (REPAS) and a 10-point numeric pain rating scale (NPRS 10). The Brunnstrom recovery stage was recorded at the beginning and at the end of the study, and the EuroQoL quality of life survey was completed at the beginning of the study, after the first month of treatment and at the end of the study. RESULTS: Patients treated with DDN showed a reduction in spasticity measured using the REPAS (p < 0.001) and the MMAS (p < 0.05). There was also an improvement in the Brunnstrom recovery stages (p < 0.05). CONCLUSION: The addition of a specific DDN treatment to a standard physiotherapy treatment appeared to lead to a higher reduction in spasticity in the affected arm; however, it did not provide additional changes in functionality, pain and quality of life. Further studies with a randomised controlled trial design are required to confirm our findings.

Effects of Deep Dry Needling on Tremor Severity and Functionality in Stroke: A Case Report.

This study aimed to determine the effect of one session of dry needling on the severity of tremor, motor function and skills, and quality of life of a 39-year-old woman with post-stroke tremor. Myofascial trigger points (MTrP) of the following muscles were treated: extensor digitorum, flexor digitorum superficialis and profundus, brachioradialis, short head of biceps brachii, long head of triceps brachii, mid deltoid, infraspinatus, teres minor, upper trapezius, and supraspinatus. Outcomes were assessed via (i) clinical scales (activity of daily living (ADL-T24), a visual analog scale (VAS), and the Archimedes spiral), (ii) a functional test (9-Hole Peg test), and (iii) biomechanical and neurophysiological measurements (inertial sensors, electromyography (EMG), and dynamometry). The subject showed a decrease in the severity of tremor during postural (72.7%) and functional (54%) tasks after treatment. EMG activity decreased after the session and returned to basal levels 4 days after. There was an improvement post-intervention (27.84 s) and 4 days after (32.43 s) in functionality and manual dexterity of the affected limb, measured with the 9-Hole Peg test, as well as in the patient's hand and lateral pinch strength after the treatment (26.9% and 5%, respectively), that was maintained 4 days later (15.4% and 16.7%, respectively).

Unimanual Intensive Therapy with or without Unaffected Hand Containment in Children with Hemiplegia. A Randomized Controlled Pilot Study.

Children with hemiplegia have lower spontaneous use and quality of movement in the affected upper limb. The modified constraint-induced movement therapy (mCIMT) is applied to improve the affected upper limb function. The objective of this study was to study the efficacy of unaffected hand containment to obtain changes in the function of the affected upper limb after applying two unimanual therapies. A randomized controlled pilot study was performed with 16 children diagnosed with congenital infantile hemiplegia, with eight children randomized in each group (average age: 5.54 years; SD: 1.55). mCIMT and unimanual therapy without containment (UTWC) were applied, with a total of 50 h distributed in five weeks (two h/per day). Two assessments were performed (pre- and post-treatment) to evaluate the affected upper limb spontaneous use, measured with the Shiners Hospital Upper Extremity Evaluation (SHUEE), and the quality of movement, measured with the Quality of Upper Extremity Skills Test (QUEST scale). The progression of the variables was different in both groups. The results are expressed in the median of the improvement percent and interquartile range (IQR). The spontaneous use analysis showed an improvement percent of 31.65 (IQR: 2.33, 110.42) in the mCIMT group with respect to 0.00 (IQR: 0.00, 0.00) in the UTWC group. The quality of movement increased in the mCIMT and UTWC groups, 24.21 (IQR: 13.44, 50.39), 1.34 (IQR: 0.00, 4.75), respectively and the greatest increase was obtained in the grasp variable for both groups. The use of unaffected hand containment in mCIMT would produce improvements in the affected upper limb functionality in children with hemiplegia (4-8 years old) compared to the same protocol without containment (UTWC).

Pressure-Induced Referred Pain as a Biomarker of Pain Sensitivity in Fibromyalgia.

BACKGROUND: Fibromyalgia (FM) syndrome is characterized by widespread pain, fatigue, and generalized increased pain sensitivity. Appropriate and simple pain models are methods employed to assess pain mechanisms that can potentially lead to improved treatments. Pressure pain thresholds (PPTs) or mapping the referred pain area produced by pressure stimulation at suprathreshold intensities are used to assess pain mechanisms. The optimal suprathreshold stimulation intensity to elicit referred pain with minimal discomfort for patients with FM has yet to be determined. OBJECTIVES: The aim of this study was to compare the area and intensity of pressure-induced referred pain in patients with FM as elicited by systematic increases in PPTs, compared with controls. STUDY DESIGN: Observational, crossed-section study. SETTING: Research laboratory. METHODS: Twenty-six patients with FM and 26 healthy controls, age- and gender-matched, were included. Suprathreshold stimulation was applied to the infraspinatus muscle of the dominant side at 4 different intensities (PPT +20%, +30%, +40%, and +50%), after which referred pain was evaluated by measuring the area of pain in pixels using a digital body chart and its intensity on a Visual Analog Scale. Factors related to anxiety condition, pain catastrophizing, depression, and quality of life were recorded. RESULTS: The referred pain areas were larger in the FM group compared with healthy individuals at 120% (P = 0.024), 130% (P = 0.001), 140% (P = 0.001), and 150% (P = 0.001) PPT, however, within the FM group no differences were found between the intensity of suprathreshold stimulation and the size of the referred pain areas (P = 0.135) or pain intensity (P > 0.05). There was a positive correlation between the size of referred pain areas and pain catastrophizing in the FM group (r = 0.457, P = 0.032). LIMITATIONS: This study presents some limitations, among which is the variability found in the referred pain areas. CONCLUSIONS: These findings show that referred pain induced by applying a suprathreshold pressure of 120% PPT can be a useful biomarker to assess sensitized pain mechanisms in patients suffering from FM. KEY WORDS: Referred pain, pain sensitivity, fibromyalgia, central sensitization, suprathreshold, pressure pain threshold, biomarker, facilitated pain mechanisms.

Combining transcranial direct-current stimulation with gait training in patients with neurological disorders: a systematic review.

BACKGROUND: Transcranial direct-current stimulation (tDCS) is an easy-to-apply, cheap, and safe technique capable of affecting cortical brain activity. However, its effectiveness has not been proven for many clinical applications. OBJECTIVE: The aim of this systematic review was to determine whether the effect of different strategies for gait training in patients with neurological disorders can be enhanced by the combined application of tDCS compared to sham stimulation. Additionally, we attempted to record and analyze tDCS parameters to optimize its efficacy. METHODS: A search in Pubmed, PEDro, and Cochrane databases was performed to find randomized clinical trials that combined tDCS with gait training. A chronological filter from 2010 to 2018 was applied and only studies with variables that quantified the gait function were included. RESULTS: A total of 274 studies were found, of which 25 met the inclusion criteria. Of them, 17 were rejected based on exclusion criteria. Finally, 8 trials were evaluated that included 91 subjects with stroke, 57 suffering from Parkinson's disease, and 39 with spinal cord injury. Four of the eight assessed studies did not report improved outcomes for any of its variables compared to the placebo treatment. CONCLUSIONS: There are no conclusive results that confirm that tDCS can enhance the effect of the different strategies for gait training. Further research for specific pathologies, with larger sample sizes and adequate follow-up periods, are required to optimize the existing protocols for applying tDCS.

Efectos analgésicos de la estimulación eléctrica nerviosa transcutánea en pacientes con fibromialgia: una revisión sistemática / Analgesic effects of transcutaneous electrical nerve stimulation (TENS) in patients with fibromyalgia: A systematic review

Objetivo: Determinar si la estimulación eléctrica nerviosa transcutánea (TENS) tiene un efecto analgésico superior al placebo o a otros tratamientos en pacientes con fibromialgia. Además, se pretendía analizar los parámetros de aplicación óptimos para conseguir una mayor reducción del dolor. Diseño: Revisión sistemática: Fuentes de datos: Ensayos clínicos aleatorizados sobre el efecto del TENS en la fibromialgia en las bases de datos Pubmed, Cochrane y PEDro hasta noviembre de 2016. Selección de estudios: Se seleccionaron 8 estudios de un total de 62. Se incluyeron ensayos clínicos controlados en los que se aplicase TENS a personas con fibromialgia. Extracción de datos: Se analizó el dolor como variable principal, aunque también se incluyeron otras variables como fatiga, calidad de vida e impacto de la enfermedad, recorrido articular y depresión. Resultados: Seis de 8 trabajos obtuvieron una disminución significativa del dolor. En 2 estudios se aplicó el TENS como tratamiento complementario al ejercicio terapéutico con resultados evidenciando una disminución del dolor. El resto de variables estudiadas presentaron gran variabilidad y no se pudieron establecer resultados concluyentes. Conclusiones: El tratamiento con TENS resulta efectivo para la disminución del dolor en personas con fibromialgia. Además, la inclusión del TENS en programas de ejercicio terapéutico parece tener un efecto superior a la realización del ejercicio terapéutico de forma aislada. Sin embargo, no se ha demostrado eficacia en otras variables diferentes al dolor. Son necesarios más estudios que indaguen en la optimización de los parámetros del TENS y un mayor consenso entre las variables utilizadas

Objective: To determine whether transcutaneous electrical nerve stimulation (TENS) has an analgesic effect greater than placebo or other treatments in patients with fibromyalgia. Furthermore, it was intended to analyze the optimal application parameters to achieve a greater reduction of pain. Design: A systematic review. Data source: Randomized clinical trials on the effect of TENS on fibromyalgia in the databases Pubmed, Cochrane and PEDro until November 2016. Selection of studies: 8 studies out of a total of 62 were selected. Controlled clinical trials in which TENS was applied in patients with fibromyalgia were included. Data extraction: Pain was analyzed as the main variable, although other variables such as fatigue, quality of life and impact, range of motion and depression were also included. Results: 6 out of 8 studies obtained a significant decrease of pain. In 2 studies, TENS was applied as complementary treatment to therapeutic exercise with results evidencing a decrease in pain. The rest of the variables studied presented a great variability and conclusive results could not be established. Conclusions: Treatment with TENS is effective for reducing pain in people with fibromyalgia. In addition, the inclusion of TENS in therapeutic exercise programs seems to have a greater effect than practicing therapeutic exercise in isolation. However, no efficacy has been demonstrated in other variables different to pain. Further studies are needed to investigate the optimization of the parameters of the TENS and a greater consensus among the variables used

Soleus H-reflex modulation following transcutaneous high- and low-frequency spinal stimulation in healthy volunteers.

The main aim of this work was to investigate the difference in the excitability of the soleus H-reflex in healthy volunteers following spinal transcutaneous electrical nerve stimulation (TENS) and high-frequency alternating current (HFAC) at a frequency of 10 kHz applied at the lower thoracic spinal level (T10-T12). A double-blind, randomized, crossover, controlled clinical trial was designed. Participants received three randomized interventions (TENS, 10 kHz, and sham stimulation) during 40 min. The amplitude and latency of the soleus H-reflex were registered prior to, during, and 10 min following stimulation. Twenty-four participants completed the study. A significant inhibition of H-reflex amplitude was observed following transcutaneous spinal TENS (12.7%; 95% CI 1.5-22.2%) when compared with sham stimulation (5.5%; 95% CI 3.6-14.5%; p = 0.03). An increase in H-reflex latency was also observed following transcutaneous spinal stimulation at 10 kHz (2%; 95% CI 1.4-2.5%) as compared with sham stimulation (0.7%; 95% CI 0.07-1.3%; p < 0.01). No differences were found between TENS and 10 kHz for H-reflex modulation. Transcutaneous spinal TENS and HFAC at a frequency of 10 kHz had a modulatory effect on the soleus H-reflex when compared to sham stimulation; however, no differences were found between these two interventions.

Does Frequency Modulation of Transcutaneous Electrical Nerve Stimulation Affect Habituation and Mechanical Hypoalgesia? A Randomized, Double-Blind, Sham-Controlled Crossover Trial.

BACKGROUND: Devices for applying transcutaneous electrical nerve stimulation (TENS) use numerous frequency modulation patterns for decreasing habituation to currents. However, there is no evidence supporting the use of an optimal pattern instead of the others, or even modulated frequencies instead of a fixed frequency. OBJECTIVE: The objectives of this study were to determine the effects of 3 TENS patterns (fixed frequency, random modulation, and 6-second-6-second [6s-6s] modulation) on habituation, to examine the subjective perception of habituation and comfort, and to determine their effects on the mechanical pain threshold (MPT). DESIGN: This study was a randomized, double-blind, sham-controlled crossover trial. SETTING: The study took place in a university research laboratory under attenuated noise conditions at a regulated temperature of 22°C to 26°C. PARTICIPANTS: Thirty-nine volunteers who were healthy participated in this trial. INTERVENTION: The participants received 4 different TENS interventions (fixed frequency, random modulation, 6s-6s modulation, and sham) in random order, with a 24-hour washout period, on the radial nerve. MEASUREMENTS: The main outcome-habituation-was quantified by the increase in current density and the number of times the intensity had to be increased during the session. Secondary outcome variables were subjective perception of habituation and comfort and MPT. RESULTS: Random modulation reduced the number of times the intensity had to be increased because of habituation compared with no modulation (1.6 times; 95% confidence interval [CI] = 0.7-2.6) and 6s-6s modulation (0.8 times; 95% CI = 0.01-1.6). No differences were observed between interventions in terms of an increase in current density, self-perceived habituation, or self-perceived comfort. MPT increased during the intervention in the random-modulation group (4.4 N; 95% CI = 1.8-7.0) and the no-modulation group (5.9 N; 95% CI = 1.9-10.0); there were no significant changes in the other 2 groups. LIMITATIONS: The success of masking or blinding procedures of the participants was not assessed. CONCLUSIONS: Randomly modulated frequencies caused less habituation than nonmodulated frequencies or 6s-6s modulation. Further research on more prolonged (hours-long) interventions in participants with pain is required.

[Analgesic effects of transcutaneous electrical nerve stimulation (TENS) in patients with fibromyalgia: A systematic review]. / Efectos analgésicos de la estimulación eléctrica nerviosa transcutánea en pacientes con fibromialgia: una revisión sistemática.

OBJECTIVE: To determine whether transcutaneous electrical nerve stimulation (TENS) has an analgesic effect greater than placebo or other treatments in patients with fibromyalgia. Furthermore, it was intended to analyze the optimal application parameters to achieve a greater reduction of pain. DESIGN: A systematic review. DATA SOURCE: Randomized clinical trials on the effect of TENS on fibromyalgia in the databases Pubmed, Cochrane and PEDro until November 2016. SELECTION OF STUDIES: 8 studies out of a total of 62 were selected. Controlled clinical trials in which TENS was applied in patients with fibromyalgia were included. DATA EXTRACTION: Pain was analyzed as the main variable, although other variables such as fatigue, quality of life and impact, range of motion and depression were also included. RESULTS: 6 out of 8 studies obtained a significant decrease of pain. In 2 studies, TENS was applied as complementary treatment to therapeutic exercise with results evidencing a decrease in pain. The rest of the variables studied presented a great variability and conclusive results could not be established. CONCLUSIONS: Treatment with TENS is effective for reducing pain in people with fibromyalgia. In addition, the inclusion of TENS in therapeutic exercise programs seems to have a greater effect than practicing therapeutic exercise in isolation. However, no efficacy has been demonstrated in other variables different to pain. Further studies are needed to investigate the optimization of the parameters of the TENS and a greater consensus among the variables used.

Afferent stimulation inhibits abnormal cutaneous reflex activity in patients with spinal cord injury spasticity syndrome.

BACKGROUND: Tibialis Anterior (TA) cutaneous reflex (CR) activity evoked following cutaneous stimulation of the plantar (Pl) surface (Pl-TA CR) has demonstrated hyperreflexia and damage of inhibitory mechanisms in subjects with spinal cord injury (SCI) and spasticity. OBJECTIVES: To modulate Pl-TA CR and Soleus H-reflex activity with transcutaneous electrical nerve stimulation (TENS) and vibratory stimulation of the plantar pad during rest and controlled isometric plantarflexion. METHODS: Non-injured subjects (n = 11) and individuals with incomplete SCI with (n = 14) and without spasticity (n = 14) were recruited. The effect of TENS and vibratory stimuli on Pl-TA CR and soleus H-reflex activity were assessed during rest and controlled ramp-and-hold plantarflexion. RESULTS: Vibration failed to inhibit H-reflex activity during rest or plantarflexoin following SCI compared to healthy subjects. In contrast, vibration-induced inhibition of Pl-TA CR was specifically detected in SCI spastic subjects during both rest and the hold phase of plantarflexion. TENS inhibited Pl-TA CR activity in the SCI spasticity group only during hold plantarflexion. CONCLUSIONS: Plantar vibratory stimuli inhibited the pl-TA CR, but not the H reflex, during rest and controlled movement in SCI spastic subjects. Assessment of Pl-TA CR modulation should contribute to the development of modality-specific sensory stimuli programmes for the neurorehabilitation of SCI spasticity.

Intensity matters: Therapist-dependent dose of spinal transcutaneous electrical nerve stimulation.

The intensity used during transcutaneous electrical nerve stimulation (TENS) in both, clinical practice and research studies, is often based on subjective commands such as "strong but comfortable sensation". There is no consensus regarding the effectiveness dose of TENS. The objective was to determine the difference in the effect of spinal TENS on soleus H-reflex modulation when applied by two therapists instructed to apply the stimulation at a "strong but comfortable" intensity. Twenty healthy volunteers divided into two groups: Therapist 1 (n = 10) and Therapist 2 (n = 10). Both therapist applied spinal TENS and sham stimulation at the T10-12 spinal level for 40min in random order to each subject, at an intensity designed to produce a "strong but comfortable" sensation. To avoid habituation, the intensity was adjusted every 2min. Soleus H-reflex was recorded before, during, and 10min after TENS by an observer blinded to the stimulus applied. Despite the instruction to apply TENS at a "strong comfortable" level, a significant difference in current density was identified: Therapist 1 (0.67mA/cm2, SD 0.54) applied more than Therapist 2 (0.53mA/cm2, SD 0.57; p<0.001) at the onset of the intervention. Maximal peak-to-peak H-reflex amplitude was inhibited significantly more 10min following TENS applied by Therapist 1 (-0.15mV, SD 0.16) compared with Therapist 2 (0.04mV, SD 0.16; p = 0.03). Furthermore, current density significantly correlated with the inhibitory effect on peak-to-peak Soleus H-reflex amplitude 10 min after stimulation (Rho = -0.38; p = 0.04). TENS intensity dosage by the therapist based on the subjective perception of the participants alone is unreliable and requires objective standardization. In addition, higher current density TENS produced greater inhibition of the Soleus H-reflex.