Transcutaneous electrical nerve stimulation for acute pain

Effects of transcutaneous electrical nerve stimulation on recovery of gastrointestinal motility after laparotomy: A randomized controlled trial

INTRODUCTION

Postoperative Ileus (POI) negatively impacts patient outcomes and increases healthcare costs. Transcutaneous electrical nerve stimulation (TENS) has been found to improve gastrointestinal (GI) motility following abdominal surgery. However, its effectiveness in this context is not well-established. This study was designed to evaluate the role of TENS on the recovery of GI motility after exploratory laparotomy.

METHODS

Patients undergoing exploratory laparotomy were randomized in a 1:1 ratio into control (standard treatment alone) and experimental (standard treatment + TENS) arms. TENS was terminated after 6 days or after the passage of stool or stoma movement. The primary outcome was time for the first passage of stool/functioning stoma. Non-passage of stool or nonfunctioning stoma beyond 6 days was labeled as prolonged POI. Patients were monitored until discharge.

RESULTS

Median (interquartile range) time to first passage of stool/functioning stoma was 82.6 (49-115) hours in the standard treatment group and 50 (22-70.6) hours in the TENS group [p < 0.001]. Prolonged POI was noted in 11 patients in the standard treatment group (35.5%) and one in the TENS group (3.2%) [p = 0.003]. Postoperative hospital stay was similar in the two groups.

CONCLUSION

TENS resulted in early recovery of GI motility by shortening the duration of POI without any improvement in postoperative hospital stay.

TRIAL REGISTRATION NUMBER

CTRI/2021/10/037054.

Pharmacological and Nonpharmacological Treatments for Painful Diabetic Peripheral Neuropathy

Diabetic peripheral neuropathy (DPN) is one of the most prevalent chronic complications of diabetes. The lifetime prevalence of DPN is thought to be >50%, and 15%-25% of patients with diabetes experience neuropathic pain, referred to as "painful DPN." Appropriate treatment of painful DPN is important because this pain contributes to a poor quality of life by causing sleep disturbance, anxiety, and depression. The basic principle for the management of painful DPN is to control hyperglycemia and other modifiable risk factors, but these may be insufficient for preventing or improving DPN. Because there is no promising diseasemodifying medication for DPN, the pain itself needs to be managed when treating painful DPN. Drugs for neuropathic pain, such as gabapentinoids, serotonin-norepinephrine reuptake inhibitors, tricyclic antidepressants, alpha-lipoic acid, sodium channel blockers, and topical capsaicin, are used for the management of painful DPN. The U.S. Food and Drug Administration (FDA) has approved pregabalin, duloxetine, tapentadol, and the 8% capsaicin patch as drugs for the treatment of painful DPN. Recently, spinal cord stimulation using electrical stimulation is approved by the FDA for the treatment for painful DPN. This review describes the currently available pharmacological and nonpharmacological treatments for painful DPN.

The potent analgesia of intrathecal 2R, 6R-HNK via TRPA1 inhibition in LF-PENS-induced chronic primary pain model

BACKGROUND

Chronic primary pain (CPP) is an intractable pain of unknown cause with significant emotional distress and/or dysfunction that is a leading factor of disability globally. The lack of a suitable animal model that mimic CPP in humans has frustrated efforts to curb disease progression. 2R, 6R-hydroxynorketamine (2R, 6R-HNK) is the major antidepressant metabolite of ketamine and also exerts antinociceptive action. However, the analgesic mechanism and whether it is effective for CPP are still unknown.

METHODS

Based on nociplastic pain is evoked by long-term potentiation (LTP)-inducible high- or low-frequency electrical stimulation (HFS/LFS), we wanted to develop a novel CPP mouse model with mood and cognitive comorbidities by noninvasive low-frequency percutaneous electrical nerve stimulation (LF-PENS). Single/repeated 2R, 6R-HNK or other drug was intraperitoneally (i.p.) or intrathecally (i.t.) injected into naïve or CPP mice to investigate their analgesic effect in CPP model. A variety of behavioral tests were used to detect the changes in pain, mood and memory. Immunofluorescent staining, western blot, reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) and calcium imaging of in cultured dorsal root ganglia (DRG) neurons by Fluo-8-AM were used to elucidate the role and mechanisms of 2R, 6R-HNK in vivo or in vitro.

RESULTS

Intrathecal 2R, 6R-HNK, rather than intraperitoneal 2R, 6R-HNK or intrathecal S-Ketamine, successfully mitigated HFS-induced pain. Importantly, intrathecal 2R, 6R-HNK displayed effective relief of bilateral pain hypersensitivity and depressive and cognitive comorbidities in a dose-dependent manner in LF-PENS-induced CPP model. Mechanically, 2R, 6R-HNK markedly attenuated neuronal hyperexcitability and the upregulation of calcitonin gene-related peptide (CGRP), transient receptor potential ankyrin 1 (TRPA1) or vanilloid-1 (TRPV1), and vesicular glutamate transporter-2 (VGLUT2) in peripheral nociceptive pathway. In addition, 2R, 6R-HNK suppressed calcium responses and CGRP overexpression in cultured DRG neurons elicited by the agonists of TRPA1 or/and TRPV1. Strikingly, the inhibitory effects of 2R, 6R-HNK on these pain-related molecules and mechanical allodynia were substantially occluded by TRPA1 antagonist menthol.

CONCLUSIONS

In the newly designed CPP model, our findings highlighted the potential utility of intrathecal 2R, 6R-HNK for preventing and therapeutic modality of CPP. TRPA1-mediated uprgulation of CGRP and neuronal hyperexcitability in nociceptive pathways may undertake both unique characteristics and solving process of CPP.

HIP Fracture REhabilitation Program for older adults with hip fracture (HIP-REP) based on activity of daily living: a feasibility study

Background

A Rehabilitation Program for older adults with hip fracture (HIP-REP) based on Activity of Daily Living has been developed. The objectives of this study were to assess the feasibility and safety of the HIP-REP program to inform a future randomized controlled trial (RCT).

Methods

A feasibility study Inspired by the Complex-intervention development (Medical Research Council framework phase II) design using quantitative and qualitative research methods were conducted. Eighteen participants (above 65 years) with hip fracture were recruited from the orthopedic wards. The setting was cross sectoral including Copenhagen University Hospital, Herlev and Gentofte and rehabilitation centers in Herlev, Gentofte and Lyngby-Taarbæk municipalities. A cross-sectoral rehabilitation intervention tailored to the needs of older adults with hip fracture highlighting systematic goal setting and strategies focused on activities of daily living was conducted. Pre-defined feasibility criteria: participants recruitment and retention, duration of measuring the outcome, adherence to intervention, and adverse events, along with self-reported outcomes and an objective measurement of performance in activity of daily living. Focus groups were analyzed using a deductive manifest content analysis approach. Descriptive statistical analysis and paired t-tests were performed for assessing change in outcome measures.

Results

Recruitment rate was 4.5/month. Outcome measures were performed but length and number of questionnaires were a burden. Thirteen out of eighteen participants completed the study three dropped out and two died. Adherence among the 13 was 100%. Focus group revealed issues regarding coordinating the intervention, ensuring procedural processes across sectors regarding recruitment of participants, and documentation in the database. Participants expressed satisfaction with the intervention and felt safe during intervention. Assessment of Motor and Process Skills showed better increase between (range 0.4 to 1.6) in ADL motor ability measures and better increase between (range 0.4 to 0.7) for process ability. No clear association between outcome improvements and intervention adherence.

Conclusions

The cross-sectoral intervention based on daily activities was feasible and safe for older adults with hip fracture. A future RCT, with an improved recruitment strategy and reduced number of outcome measures will evaluate the effectiveness in improving independence and safety performance of activity of daily living.

Trial registration

ClinicalTrials.gov ID: NCT03828240. Registered on January 29, 2019.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03039-x.

Does TENS Reduce the Intensity of Acute and Chronic Pain? A Comprehensive Appraisal of the Characteristics and Outcomes of 169 Reviews and 49 Meta-Analyses

Background and Objectives: Uncertainty about the clinical efficacy of transcutaneous electric nerve stimulation (TENS) to alleviate pain spans half a century. There has been no attempt to synthesise the entire body of systematic review evidence. The aim of this comprehensive review was to critically appraise the characteristics and outcomes of systematic reviews evaluating the clinical efficacy of TENS for any type of acute and chronic pain in adults. Materials and Methods: We searched electronic databases for full reports of systematic reviews of studies, overviews of systematic reviews, and hybrid reviews that evaluated the efficacy of TENS for any type of clinical pain in adults. We screened reports against eligibility criteria and extracted data related to the characteristics and outcomes of the review, including effect size estimates. We conducted a descriptive analysis of extracted data. Results: We included 169 reviews consisting of eight overviews, seven hybrid reviews and 154 systematic reviews with 49 meta-analyses. A tally of authors' conclusions found a tendency toward benefits from TENS in 69/169 reviews, no benefits in 13/169 reviews, and inconclusive evidence in 87/169 reviews. Only three meta-analyses pooled sufficient data to have confidence in the effect size estimate (i.e., pooled analysis of >500 events). Lower pain intensity was found during TENS compared with control for chronic musculoskeletal pain and labour pain, and lower analgesic consumption was found post-surgery during TENS. The appraisal revealed repeated shortcomings in RCTs that have hindered confident judgements about efficacy, resulting in stagnation of evidence. Conclusions: Our appraisal reveals examples of meta-analyses with 'sufficient data' demonstrating benefit. There were no examples of meta-analyses with 'sufficient data' demonstrating no benefit. Therefore, we recommend that TENS should be considered as a treatment option. The considerable quantity of reviews with 'insufficient data' and meaningless findings have clouded the issue of efficacy. We offer solutions to these issues going forward.

Pain management for in-office hysteroscopy. A practical decalogue for the operator

Hysteroscopy is known to be the gold standard for evaluation of intrauterine pathologies, pre-menopausal and post-menopausal abnormal uterine bleeding and, in addition to this, it is a crucial examination in the infertility work-up. In-office operative hysteroscopy incorporates the outstanding possibility of seeing and treating an intracavitary pathology in the same examination, eliminating all the risk related to anesthesia and reducing procedure-related costs. By now, performing operative procedures in the office setting is recognized as feasible and safe. Over the last 20 years, many efforts have been made to implement the in-office operative approach worldwide. However, for some women, in-office hysteroscopy is still considered a painful experience, with reported discomfort at different steps of the hysteroscopic procedures. Moreover, uneventful and tedious sensations might be increased by a high level of anxiety for such examination. For this reason, despite the feasibility of the in-office approach, many clinicians are still afraid of provoking pain during the procedure and rather not to perform surgical procedures in the office, postponing the removal of the pathology in the operating room. To date, there is no consensus concerning pain management for in-office hysteroscopy and different approaches, pharmacological and non-pharmacological aids, as well as several procedural tips and tricks are utilized. Our purpose is to provide a feasible practical decalogue for the operator, to supply adequate management of pain during in-office hysteroscopic procedures, performing challenging operations, shrinking discomfort, aiming to upgrade both women's and operator's satisfaction.

The Effects of Transcutaneous Electrical Nerve Stimulation on Post-Episiotomy Pain Severity in Primiparous Women: A Randomized, Controlled, Placebo Clinical Trial

Background:

Episiotomy or cutting the perineum is the most common operation in obstetrics. Perineal pain is the main complication of episiotomy that affects the quality of life and mental health of the mother. Reducing the pain and side effects of the chemical drugs prescribed for pain relief has attracted the attention of both physicians and scientists. This study was conducted to determine the effects of transcutaneous electrical nerve stimulation (TENS), as an alternative method, on post-episiotomy pain severity.

Materials and Methods:

This randomized clinical trial was performed on 120 primiparous women who had referred to Sanandaj Besat Hospital in 2018. The patients were divided randomly into three groups, including the intervention group (TENS-On), the placebo group (TENS-Off), and the control group. TENS electrodes were placed near the episiotomy site in genitofemoral and pudendal nerves. The pain was measured after episiotomy in lying, sitting, and activity positions. The pain severity was measured using a pain measurement instrument (numeral rating score) at four-time points, i.e., before the intervention as well as 30, 60, and 120 minutes after the TENS intervention. For data analysis, Pearson correlation, student’s t-test, Kruskal-Wallis test, ANOVA test, and Mann-Whitney U tests were used.

Results:

Intragroup evaluation results for placebo and control groups demonstrated no significant difference in the pain score (P>0.05). A significant difference was observed between the mean pain severity of the intervention group and that of the group with walking activities (P=0.04). In terms of the intergroup evaluation, there was a significant difference observed between the mean pain severity of the lying position and that of the control group (P=0.008). Regarding the sitting position, no significant difference was observed between its mean pain severity and that of the other two groups (P=0.04).

Conclusion:

TENS is an effective and safe method for post-episiotomy pain relief and a routine method used in the obstetrics and gynecology ward.

Efficacy of different-frequency TEAS on acute pain after the total knee arthroplasty: a study protocol for a parallel group randomized trial

BACKGROUND

Total knee arthroplasty (TKA) is an optimal option for patients with middle-to-end-stage knee osteoarthritis. However, the management of postoperative acute pain remains inefficient. Transcutaneous electrical acupoint stimulation (TEAS) is a nonpharmacological method to manage postoperative acute pain. Different frequencies of TEAS have been tested using varying parameters, but the optimal analgesic frequency remains controversial. The aim of this study was to explore the optimal analgesic frequency of TEAS for treating acute pain after the primary unilateral TKA.

METHODS/DESIGN

This is a double-blind, randomized controlled trial. A total of 156 patients are randomly assigned to: G1, 5 Hz TEAS; G2, 100 Hz TEAS; G3, mixed TEAS (alternative use of daily 5 Hz and 100 Hz TEAS) and G4, placebo TEAS. In the G1, G2 and G3 groups, TEAS is conducted at acupoints SP9 and GB34 of the leg that was operated on (at a wave of continuous, balanced and asymmetrical biphasic square, with a pulse width of 200 μs, and a strong but comfortable current) for 30 min prior to a 30-min rehabilitation session per day for 2 weeks. In G4 group, TEAS is delivered at a strong but comfortable current for 30 s, then the current is gradually decreased to none over the next 15 s. The primary outcomes are measured before surgery, at baseline (POD 3, before TEAS intervention), week 1 and 2 after TEAS intervention with the Numeric Pain Rating Scale and The American Knee Society Score. The secondary outcomes include: (1) Active range of motion of the knee that was operated on; (2) Surface electromyography of both quadriceps; (3) Modified 30-s sit to stand test; (4) Additional usage of analgesia; and (5) SF-36. The additional outcomes include: (1) Patients' satisfaction rate; (2) Patient's expectation rate; and (3) Incidence of analgesia-related side effects. To test the blinding of participants and assessors, they are asked to guess whether the subjects received active or placebo TEAS within 5 min after the latest intervention. The safety and financial cost of TEAS are assessed.

DISCUSSION

Mixed TEAS has more favorable effect on acute pain control than the placebo or 5 Hz or 100 Hz TEAS.

TRIAL REGISTRATION

ChiCTR1800016347 . Date of registration was 26 May 2018. Retrospectively registered.

Effects of transcutaneous electrical nerve stimulation on pain after impacted third molar surgery

Background

The aim of this study was to assess the therapeutic effects of Transcutaneous Electrical Nerve Stimulation (TENS) on pain after the impacted third molar surgery.

Material and Methods

The study was carried out on 30 patients attending the outpatient department of the oral and maxillofacial surgery. Both sides’ impacted mandibular third molars were taken into consideration, and a total of 60 impacted third molars were undergone surgical extraction. After the first surgery, patients were given analgesic, antibiotics, and mouthwash as a routine treatment procedure. Following the second surgery, TENS was applied over the painful area of the cheek for patients in addition to routine treatment procedure. Pain was evaluated with Visual Analog Scale (VAS) at the postoperative 6, 8, 24 hours and 2,3,4 and 5 days. The Student t test was applied to compare pain levels between groups. P<0.05 and p<0.001 were considered significant in all statistical analyses.

Results

The study was carried out in 30 patients 15 (50%) female and 15 (50%) male, aged between 20 and 31 years. The mean age of the patients was 24.60 ± 4.76. There was a statistically significant difference in the evaluation of VAS levels in postoperative 6, 8, 24 hours and 2, 3, 4, and 5 days between the routine treatment group and the TENS application group.

Conclusions

TENS activates a complex neuronal network to result in a reduction in pain. In conclusion, TENS application was highly effective in pain modulation following the third molar surgery. Therefore, TENS, which is one of the non-pharmacological pain control methods after such surgeries, can be used safely in reducing postoperative pain.

Key words:Impacted teeth, third molar, pain, transcutaneous electrical nerve stimulation.

Assessing and Treating Chronic Pain in Patients with End-Stage Renal Disease

Pain is one of the most common symptoms among patients with end-stage renal disease (ESRD), and is often under recognized and not adequately managed in hemodialysis (HD) patients. Barriers to adequate pain management include poor awareness of the problem, insufficient medical education, fears of possible drug-related side effects, and common misconceptions about the inevitability of pain in elderly and HD patients. Caregivers working in HD should be aware of the possible consequences of inadequate pain assessment and management. Common pain syndromes in HD patients include musculoskeletal diseases and metabolic neuropathies, associated with typical intradialytic pain. Evaluating the etiology, nature, and intensity of pain is crucial for choosing the correct analgesic. A mechanism-based approach to pain management may result in a better outcome. Pharmacokinetic considerations on clearance alterations and possible toxicity in patients with ESRD should drive the right analgesic prescription. Comorbidities and polymedications may increase the risk of drug-drug interactions, therefore drug metabolism should be taken into account when selecting analgesic drugs. Automedication is common among HD patients but should be avoided to reduce the risk of hazardous drug administration. Further research is warranted to define the efficacy and safety of analgesic drugs and techniques in the context of patients with ESRD as generalizing information from studies conducted in the general population could be inappropriate and potentially dangerous. A multidisciplinary approach is recommended for the management of complex pain syndromes in frail patients, such as those suffering from ESRD.

Comparison of the Efficacy of Conventional Physical Therapy Modalities and Kinesio Taping Treatments in Shoulder Impingement Syndrome

Objective

The aim of the present study was to compare the effectiveness of kinesio taping (KT) treatments and conventional physical therapy (PT) modalities that are applied to reduce pain and improve physical movements and functions of patients with sub acromial impingement syndrome (SIS).

Materials and Methods

Forty patients were randomly divided into two equal groups. The first group was assigned KT plus home exercise program (HEP) for 15 days. The second group was given 15 sessions of PT and HEP. Patients were assessed using active joint range of motion (ROM), Visual Analogue Scale (VAS; rest, movement, and night pain), the Society of the American Shoulder and Elbow Surgeons Evaluation (ASESS-100), Constant-Murley (C-M) scale, and Western Ontario Rotator Cuff (WORC) index at before and after treatment and at the end of the study (first month control visit).

Results

Physical therapy was found to be more effective than KT when these two treatment modalities were assessed based on ASESS-100, WORC index values, night pain, and movement pain. PT and KT treatments have similar effects in active ROM, rest pain, and C-M scale. At the end of the study, they were found to have similar effects except the night pain value. PT was found to be more effective for night pain than KT.

Conclusion

Physical therapy was concluded to be more effective after treatment. The application of KT does not appear to be an alternative treatment method for SIS, but it can provide a potential supportive care for SIS. However, the outcomes suggest that KT can provide a remarkable benefit.

Pain management of surgical abortion using transcutaneous acupoint electrical stimulation: An orthogonal prospective study

Aim

This study aimed to evaluate the optimal combination of parameters for the management of pain during surgical abortion using transcutaneous acupoint electrical stimulation (TEAS).

Methods

This study recruited patients scheduled for surgical abortion between October 2014 and August 2015. The treatment protocol was created using three levels for each factor (stimulating time, acupoints, age, and parity). The primary outcomes were intraoperative visual analog scale (VAS), postoperative VAS, cervical relaxation degree and intraoperative blood loss. The secondary outcomes were the vital signs.

Results

Stimulation time was associated with intraoperative VAS scores (P < 0.001), acupoints were associated with postoperative VAS scores (P = 0.037), and age was associated with postoperative VAS scores (P < 0.043). Parity (P = 0.025) was associated with heart rate. A comprehensive analysis of the parameters revealed the best levels for each (stimulation time: from 15 min before operation to immediate postoperative; acupoints: SP 6 and LR 3; patient age 25.1–30.0 years; and parity: G_≥2P₀A_≥1). Seven patients did not complete follow‐up. The remaining 135 subjects did not show continuous vaginal bleeding, abdominal pain, fever or any other adverse effect.

Conclusion

During surgical abortion, TEAS stimulation from 15 min before operation to immediate postoperative, SP 6 and LR 3, age 25.1–30.0 years and G_≥2P₀A_≥1 were associated with the best analgesic effect.

No immediate analgesic effect of diadynamic current in patients with nonspecific low back pain in comparison to TENS

BACKGROUND AND DESIGN

Chronic nonspecific low back pain (CNSLBP) has major socioeconomic as well as personal impact in many industrialized and developing countries. Physiotherapy is a common intervention for this group of patients and using anti-pain physical modalities is a common part of the physical therapy. In a randomized controlled trial we investigated the immediate effect of the Diadynamic current in comparison to TENS on reducing the pain in patients suffering from non specific chronic low back pain.

METHODS

Thirty patients were randomized into the Diadynamic current and TENS groups. Electrical stimulation was applied for 10 min in the Diadynamic group and for 15 min in the TENS group for one session. Pain, on a 100 mm Visual Analog Scale, and Pressure Pain Threshold (PPT), using an Algometer, was measured before the treatment, after the current application, 20 min later and after 48 h.

RESULTS

Pain was decreased significantly after 20 min following the current application only in the TENS group, with no improvement at all measurement points in the group receiving Diadynamic current. PPT was increased immediately after current application in both groups but did not last until later measurements.

CONCLUSION

Diadynamic current had no positive effect on prompt relief of pain in patients suffering from recurrent CNSLBP.

Impact of electro-neuro-feedback on postoperative outcome of impacted lower third molar surgery

Objective

The purpose of this study was to evaluate the impact of a treatment with electro-neuro-feedback (ENF), a portable transcutaneous electrical nerve stimulation (TENS) device, on the clinical outcome and inflammatory biochemical parameters related to the impacted lower third molar surgery.

Materials and Methods

A randomized, split-mouth, and single-blind study was conducted on 32 patients requiring lower third molars extractions and referred to the Oral Surgery Unit of the School of Dentistry of the University of Messina. Every patient underwent surgical removal of both lower third molars. The first extraction included a placebo (electrodes placement with turned-off device) treatment following the surgery, while the second had the ENF used next to the avulsion and the following days. Clinical parameters were collected 4 days before, immediately after, 2, 4, and 7 days after the surgical procedure. Biochemical parameters were obtained 1 day before the surgical removal and 7 days after. Data were processed using Wilcoxon-Mann-Whitney test, with significance being set at P < 0.05.

Results

Clinical outcome parameters showed a significant improvement after the ENF treatment, while considered inflammatory markers expressed different patterns.

Conclusions

ENF, a reliable portable TENS device, has demonstrated to be a useful tool in the managing of the postsurgical phases, reducing edema, pain, and consequent pain-killers consumption.

A Comparative Study between Transcutaneous Electrical Nerve Stimulation and Fentanyl to Relieve Shoulder Pain during Laparoscopic Gynecologic Surgery under Spinal Anesthesia: A Randomized Clinical Trail

Background

Traditionally, laparoscopic procedures have been performed under general anesthesia. Spinal anesthesia is an effective alternative to general anesthesia. However, one of the intraoperative complications of performing laparoscopic surgery under spinal anesthesia is shoulder pain. This study aimed to compare the effect of transcutaneous electrical nerve stimulation (TENS) with fentanyl on pain relief in patients who underwent gynecologic laparoscopy under spinal anesthesia.

Methods

We conducted a prospective randomized clinical trial from May 2016 to March 2017. A sample of patients who underwent gynecological laparoscopy under spinal anesthesia was recruited. If they had shoulder pain, they randomly received either transcutaneous electrical nerve stimulation (TENS) or 50 mg of fentanyl. Pain intensity was measured using the single item visual analogue scale (VAS-10 cm) immediately before and 5, 10, 20, and 30 minutes after treatment. Also, the effect of higher doses of analgesia on pain relief was analyzed.

Results

In all, 80 patients (40 patients in each group) were entered into the study. The mean pain intensity score was 9.02 ± 1.32 in the TENS group and 8.95 ± 1.33 in the fentanyl group at baseline (P = 0.80). Repeated measures analysis of variance indicated that there was no significant difference on overall pain scores between the two treatment groups adjusted for age, BMI, total analgesia used, and baseline pain score (F (1, 74) = 1.44, P = 0.23). The use of analgesic drugs in the TENS group was significantly higher than the fentanyl group (P = 0.01). In addition, we found that nine patients (22.5%) complained of nausea/vomiting in the TENS group compared to thirteen patients (32.5%) in the fentanyl group (P = 0.31).

Conclusions

The findings indicated that TENS was not superior to fentanyl for pain relief in laparoscopic surgery. It seems that the correct use of TENS parameters might merit further investigation. This trial is registered with: IRCT2016031216765N3.

Transcutaneous electrical nerve stimulation (TENS) for neuropathic pain in adults

BACKGROUND

Neuropathic pain, which is due to nerve disease or damage, represents a significant burden on people and society. It can be particularly unpleasant and achieving adequate symptom control can be difficult. Non-pharmacological methods of treatment are often employed by people with neuropathic pain and may include transcutaneous electrical nerve stimulation (TENS). This review supersedes one Cochrane Review 'Transcutaneous electrical nerve stimulation (TENS) for chronic pain' (Nnoaham 2014) and one withdrawn protocol 'Transcutaneous electrical nerve stimulation (TENS) for neuropathic pain in adults' (Claydon 2014). This review replaces the original protocol for neuropathic pain that was withdrawn.

OBJECTIVES

To determine the analgesic effectiveness of TENS versus placebo (sham) TENS, TENS versus usual care, TENS versus no treatment and TENS in addition to usual care versus usual care alone in the management of neuropathic pain in adults.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, PsycINFO, AMED, CINAHL, Web of Science, PEDro, LILACS (up to September 2016) and various clinical trials registries. We also searched bibliographies of included studies for further relevant studies.

SELECTION CRITERIA

We included randomised controlled trials where TENS was evaluated in the treatment of central or peripheral neuropathic pain. We included studies if they investigated the following: TENS versus placebo (sham) TENS, TENS versus usual care, TENS versus no treatment and TENS in addition to usual care versus usual care alone in the management of neuropathic pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened all database search results and identified papers requiring full-text assessment. Subsequently, two review authors independently applied inclusion/exclusion criteria to these studies. The same review authors then independently extracted data, assessed for risk of bias using the Cochrane standard tool and rated the quality of evidence using GRADE.

MAIN RESULTS

We included 15 studies with 724 participants. We found a range of treatment protocols in terms of duration of care, TENS application times and intensity of application. Briefly, duration of care ranged from four days through to three months. Similarly, we found variation of TENS application times; from 15 minutes up to hourly sessions applied four times daily. We typically found intensity of TENS set to comfortable perceptible tingling with very few studies titrating the dose to maintain this perception. Of the comparisons, we had planned to explore, we were only able to undertake a quantitative synthesis for TENS versus sham TENS. Insufficient data and large diversity in the control conditions prevented us from undertaking a quantitative synthesis for the remaining comparisons.For TENS compared to sham TENS, five studies were suitable for pooled analysis. We described the remainder of the studies in narrative form. Overall, we judged 11 studies at high risk of bias, and four at unclear risk. Due to the small number of eligible studies, the high levels of risk of bias across the studies and small sample sizes, we rated the quality of the evidence as very low for the pooled analysis and very low individual GRADE rating of outcomes from single studies. For the individual studies discussed in narrative form, the methodological limitations, quality of reporting and heterogeneous nature of interventions compared did not allow for reliable overall estimates of the effect of TENS.Five studies (across various neuropathic conditions) were suitable for pooled analysis of TENS versus sham TENS investigating change in pain intensity using a visual analogue scale. We found a mean postintervention difference in effect size favouring TENS of -1.58 (95% confidence interval (CI) -2.08 to -1.09, P < 0.00001, n = 207, six comparisons from five studies) (very low quality evidence). There was no significant heterogeneity in this analysis. While this exceeded our prespecified minimally important difference for pain outcomes, we assessed the quality of evidence as very low meaning we have very little confidence in this effect estimate and the true effect is likely to be substantially different from that reported in this review. Only one study of these five investigated health related quality of life as an outcome meaning we were unable to report on this outcome in this comparison. Similarly, we were unable to report on global impression of change or changes in analgesic use in this pooled analysis.Ten small studies compared TENS to some form of usual care. However, there was great diversity in what constituted usual care, precluding pooling of data. Most of these studies found either no difference in pain outcomes between TENS versus other active treatments or favoured the comparator intervention (very low quality evidence). We were unable to report on other primary and secondary outcomes in these single trials (health-related quality of life, global impression of change and changes in analgesic use).Of the 15 included studies, three reported adverse events which were minor and limited to 'skin irritation' at or around the site of electrode placement (very low quality evidence). Three studies reported no adverse events while the remainder did not report any detail with regard adverse events.

AUTHORS' CONCLUSIONS

In this review, we reported on the comparison between TENS and sham TENS. The quality of the evidence was very low meaning we were unable to confidently state whether TENS is effective for pain control in people with neuropathic pain. The very low quality of evidence means we have very limited confidence in the effect estimate reported; the true effect is likely to be substantially different. We make recommendations with respect to future TENS study designs which may meaningfully reduce the uncertainty relating to the effectiveness of this treatment modality.

Effect of Peripheral Electrical Stimulation (PES) on Nocturnal Blood Glucose in Type 2 Diabetes: A Randomized Crossover Pilot Study

BACKGROUND

Regulation of hepatic glucose production has been a target for antidiabetic drug development, due to its major contribution to glucose homeostasis. Previous pre-clinical study demonstrated that peripheral electrical stimulation (PES) may stimulate glucose utilization and improve hepatic insulin sensitivity. The aim of the present study was to evaluate safety, tolerability, and the glucose-lowering effect of this approach in patients with type 2 diabetes (T2DM).

METHODS

Twelve patients with T2DM were recruited for an open label, interventional, randomized trial. Eleven patients underwent, in a crossover design, an active, and a no-intervention control periods, separated with a two-week washout phase. During the active period, the patients received a daily lower extremity PES treatment (1.33Hz/16Hz burst mode), for 14 days. Study endpoints included changes in glucose levels, number of hypoglycemic episodes, and other potential side effects. Endpoints were analyzed based on continuous glucose meter readings, and laboratory evaluation.

RESULTS

We found that during the active period, the most significant effect was on nocturnal glucose control (P < 0.0004), as well as on pre-meal mean glucose levels (P < 0.02). The mean daily glucose levels were also decreased although it did not reach clinical significance (P = 0.07). A reduction in serum cortisol (P < 0.01) but not in insulin was also detected after 2 weeks of treatment. No adverse events were recorded.

CONCLUSIONS

These results indicate that repeated PES treatment, even for a very short duration, can improve blood glucose control, possibly by suppressing hepatic glucose production. This effect may be mediated via hypothalamic-pituitary-adrenal axis modulation.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02727790.

Transcutaneous electrical stimulation (TES) for treatment of constipation in children

BACKGROUND

Childhood constipation is a common problem with substantial health, economic and emotional burdens. Existing therapeutic options, mainly pharmacological, are not consistently effective, and some are associated with adverse effects after prolonged use. Transcutaneous electrical stimulation (TES), a non-pharmacological approach, is postulated to facilitate bowel movement by modulating the nerves of the large bowel via the application of electrical current transmitted through the abdominal wall.

OBJECTIVES

Our main objective was to evaluate the effectiveness and safety of TES when employed to improve bowel function and constipation-related symptoms in children with constipation.

SEARCH METHODS

We searched MEDLINE (PubMed) (1950 to July 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 7, 2015), EMBASE (1980 to July 2015), the Cochrane IBD Group Specialized Register, trial registries and conference proceedings to identify applicable studies .

SELECTION CRITERIA

Randomized controlled trials that assessed any type of TES, administered at home or in a clinical setting, compared to no treatment, a sham TES, other forms of nerve stimulation or any other pharmaceutical or non-pharmaceutical measures used to treat constipation in children were considered for inclusion.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for inclusion, extracted data and assessed risk of bias of the included studies. We calculated the risk ratio (RR) and corresponding 95% confidence interval (CI) for categorical outcomes data and the mean difference (MD) and corresponding 95% CI for continuous outcomes. We evaluated the overall quality of the evidence supporting the outcomes assessed in this review using the GRADE criteria.

MAIN RESULTS

One study from Australia including 46 children aged 8 to 18 years was eligible for inclusion. There were multiple reports identified, including one unpublished report, that focused on different outcomes of the same study. The study had unclear risk of selection bias, high risks of performance, detection and attrition biases, and low risks of reporting biases.We are very uncertain about the effects of TES on bowel movements, colonic transit, soiling symptoms and quality of life due to high risk of bias, indirectness and imprecision. For our outcomes of interest the 95% CI of most analysis results include potential benefit and no effect. There is insufficient evidence to determine the effect of TES on bowel movements and colonic transit. The study reported that 16/21 children in the TES group and 15/21 in the sham group had > 3 complete spontaneous bowel movements (CSBM) per week (RR 1.07, 95% CI 0.74 to 1.53; very low-quality evidence). Ten out of 14 children in the TES group had improved colonic transit compared to 1/7 in the sham group (RR 5.00, 95% CI 0.79 to 31.63; very low-quality evidence). Mean colonic transit rate, measured as the position of the geometric centre of the radioactive substance ingested along the intestinal tract, was higher in children who received TES compared to sham (MD 1.05, 95% CI 0.36 to 1.74; one study, 30 participants; very low-quality evidence). The radiological assessment of colonic transit outcomes means that these results might not translate to important improvement in clinical symptoms or increased bowel movements. There is insufficient evidence to determine the effect of TES on symptoms and quality of life (QoL) outcomes. Nine out of 13 children in the TES group had improved soiling-related symptoms compared to 4/12 sham participants (RR 2.08, 95% CI 0.86 to 5.00; very low-quality evidence). Four out of 8 TES participants reported an improvement in QoL compared to 1/8 sham participants (RR 4.00, 95% CI 0.56 to 28.40; very low-quality evidence). The effects of TES on self-perceived (MD 5.00, 95% CI -1.21 to 11.21; one study, 33 participants; very low-quality evidence) or parent-perceived QoL (MD -0.20, 95% CI -7.57 to 7.17, one study, 33 participants; very low-quality evidence) are uncertain. No adverse effects were reported in the included study.

AUTHORS' CONCLUSIONS

The results for the outcomes assessed in this review are uncertain. Thus no firm conclusions regarding the efficacy and safety of TES in children with chronic constipation can be drawn. Further randomized controlled trials assessing TES for the management of childhood constipation should be conducted. Future trials should include clear documentation of methodologies, especially measures to evaluate the effectiveness of blinding, and incorporate patient-important outcomes such as the number of patients with improved CSBM, improved clinical symptoms and quality of life.

WITHDRAWN: Transcutaneous electrical stimulation (TES) for treatment of constipation in children

BACKGROUND

Childhood constipation is a common problem with substantial health, economic and emotional burdens. Existing therapeutic options, mainly pharmacological, are not consistently effective, and some are associated with adverse effects after prolonged use. Transcutaneous electrical stimulation (TES), a non-pharmacological approach, is postulated to facilitate bowel movement by modulating the nerves of the large bowel via the application of electrical current transmitted through the abdominal wall.

OBJECTIVES

Our main objective was to evaluate the effectiveness and safety of TES when employed to improve bowel function and constipation-related symptoms in children with constipation.

SEARCH METHODS

We searched MEDLINE (PubMed) (1950 to July 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 7, 2015), EMBASE (1980 to July 2015), the Cochrane IBD Group Specialized Register, trial registries and conference proceedings to identify applicable studies .

SELECTION CRITERIA

Randomized controlled trials that assessed any type of TES, administered at home or in a clinical setting, compared to no treatment, a sham TES, other forms of nerve stimulation or any other pharmaceutical or non-pharmaceutical measures used to treat constipation in children were considered for inclusion.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for inclusion, extracted data and assessed risk of bias of the included studies. We calculated the risk ratio (RR) and corresponding 95% confidence interval (CI) for categorical outcomes data and the mean difference (MD) and corresponding 95% CI for continuous outcomes.

MAIN RESULTS

One study from Australia including 46 children aged 8 to 18 years was eligible for inclusion. There were multiple reports identified, including one unpublished report, that focused on different outcomes of the same study. The study had unclear risk of selection bias, high risks of performance, detection and attrition biases, and low risks of reporting biases.There were no significant differences between TES and the sham control group for the following outcomes: i).number of children with > 3 complete spontaneous bowel movements (CSBM) per week (RR 1.07, 95% CI 0.74 to 1.53, one study, 42 participants) (Quality of evidence: very low, due to high risk of bias and serious imprecision ), ii). number of children with improved colonic transit assessed radiologically (RR 5.00, 95% CI 0.79 to 31.63; one study, 21 participants) (Quality of evidence: very low, due to high risk of bias, serious imprecision and indirectness of the outcome). However, mean colonic transit rate, measured as the position of the geometric centre of the radioactive substance ingested along the intestinal tract, was significantly higher in children who received TES compared to sham (MD 1.05, 95% CI 0.36 to 1.74; one study, 30 participants) (Quality of evidence: very low, due to high risk of bias , serious imprecision and indirectness of the outcome). There was no significant difference between the two groups in the number of children with improved soiling-related symptoms (RR 2.08, 95% CI 0.86 to 5.00; one study, 25 participants) (Quality of evidence: very low, due to high risk of bias and serious imprecision). There was no significant difference in the number of children with improved quality of life (QoL) (RR 4.00, 95% CI 0.56 to 28.40; one study, 16 participants) (Quality of evidence: very low, due to high risk of bias issues and serious imprecision ). There were also no significant differences in in self-perceived (MD 5.00, 95% CI -1.21 to 11.21) or parent-perceived QoL (MD -0.20, 95% CI -7.57 to 7.17, one study, 33 participants for both outcomes) (Quality of evidence for both outcomes: very low, due to high risk of bias and serious imprecision). No adverse effects were reported in the included study.

AUTHORS' CONCLUSIONS

The results for the outcomes assessed in this review are uncertain. Thus no firm conclusions regarding the efficacy and safety of TES in children with chronic constipation can be drawn. Further randomized controlled trials assessing TES for the management of childhood constipation should be conducted. Future trials should include clear documentation of methodologies, especially measures to evaluate the effectiveness of blinding, and incorporate patient-important outcomes such as the number of patients with improved CSBM, improved clinical symptoms and quality of life.

Transcutaneous electrical stimulation (TES) for treatment of constipation in children

BACKGROUND

Childhood constipation is a common problem with substantial health, economic and emotional burdens. Existing therapeutic options, mainly pharmacological, are not consistently effective, and some are associated with adverse effects after prolonged use. Transcutaneous electrical stimulation (TES), a non-pharmacological approach, is postulated to facilitate bowel movement by modulating the nerves of the large bowel via the application of electrical current transmitted through the abdominal wall.

OBJECTIVES

Our main objective was to evaluate the effectiveness and safety of TES when employed to improve bowel function and constipation-related symptoms in children with constipation.

SEARCH METHODS

We searched MEDLINE (PubMed) (1950 to July 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 7, 2015), EMBASE (1980 to July 2015), the Cochrane IBD Group Specialized Register, trial registries and conference proceedings to identify applicable studies .

SELECTION CRITERIA

Randomized controlled trials that assessed any type of TES, administered at home or in a clinical setting, compared to no treatment, a sham TES, other forms of nerve stimulation or any other pharmaceutical or non-pharmaceutical measures used to treat constipation in children were considered for inclusion.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for inclusion, extracted data and assessed risk of bias of the included studies. We calculated the risk ratio (RR) and corresponding 95% confidence interval (CI) for categorical outcomes data and the mean difference (MD) and corresponding 95% CI for continuous outcomes.

MAIN RESULTS

One study from Australia including 46 children aged 8 to 18 years was eligible for inclusion. There were multiple reports identified, including one unpublished report, that focused on different outcomes of the same study. The study had unclear risk of selection bias, high risks of performance, detection and attrition biases, and low risks of reporting biases.There were no significant differences between TES and the sham control group for the following outcomes: i).number of children with > 3 complete spontaneous bowel movements (CSBM) per week (RR 1.07, 95% CI 0.74 to 1.53, one study, 42 participants) (

QUALITY OF EVIDENCE

very low, due to high risk of bias and serious imprecision ), ii). number of children with improved colonic transit assessed radiologically (RR 5.00, 95% CI 0.79 to 31.63; one study, 21 participants) (

QUALITY OF EVIDENCE

very low, due to high risk of bias, serious imprecision and indirectness of the outcome). However, mean colonic transit rate, measured as the position of the geometric centre of the radioactive substance ingested along the intestinal tract, was significantly higher in children who received TES compared to sham (MD 1.05, 95% CI 0.36 to 1.74; one study, 30 participants) (

QUALITY OF EVIDENCE

very low, due to high risk of bias , serious imprecision and indirectness of the outcome). There was no significant difference between the two groups in the number of children with improved soiling-related symptoms (RR 2.08, 95% CI 0.86 to 5.00; one study, 25 participants) (

QUALITY OF EVIDENCE

very low, due to high risk of bias and serious imprecision). There was no significant difference in the number of children with improved quality of life (QoL) (RR 4.00, 95% CI 0.56 to 28.40; one study, 16 participants) (

QUALITY OF EVIDENCE

very low, due to high risk of bias issues and serious imprecision ). There were also no significant differences in in self-perceived (MD 5.00, 95% CI -1.21 to 11.21) or parent-perceived QoL (MD -0.20, 95% CI -7.57 to 7.17, one study, 33 participants for both outcomes) (QUALITY OF EVIDENCE for both outcomes: very low, due to high risk of bias and serious imprecision). No adverse effects were reported in the included study.

AUTHORS' CONCLUSIONS

The very low quality evidence gathered in this review does not suggest that TES provides a benefit for children with chronic constipation. Further randomized controlled trials assessing TES for the management of childhood constipation should be conducted. Future trials should include clear documentation of methodologies, especially measures to evaluate the effectiveness of blinding, and incorporate patient-important outcomes such as the number of patients with improved CSBM, improved clinical symptoms and quality of life.

Electrotherapy modalities for rotator cuff disease

BACKGROUND

Management of rotator cuff disease may include use of electrotherapy modalities (also known as electrophysical agents), which aim to reduce pain and improve function via an increase in energy (electrical, sound, light, or thermal) into the body. Examples include therapeutic ultrasound, low-level laser therapy (LLLT), transcutaneous electrical nerve stimulation (TENS), and pulsed electromagnetic field therapy (PEMF). These modalities are usually delivered as components of a physical therapy intervention. This review is one of a series of reviews that form an update of the Cochrane review, 'Physiotherapy interventions for shoulder pain'.

OBJECTIVES

To synthesise available evidence regarding the benefits and harms of electrotherapy modalities for the treatment of people with rotator cuff disease.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 3), Ovid MEDLINE (January 1966 to March 2015), Ovid EMBASE (January 1980 to March 2015), CINAHL Plus (EBSCOhost, January 1937 to March 2015), ClinicalTrials.gov and the WHO ICTRP clinical trials registries up to March 2015, unrestricted by language, and reviewed the reference lists of review articles and retrieved trials, to identify potentially relevant trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-randomised trials, including adults with rotator cuff disease (e.g. subacromial impingement syndrome, rotator cuff tendinitis, calcific tendinitis), and comparing any electrotherapy modality with placebo, no intervention, a different electrotherapy modality or any other intervention (e.g. glucocorticoid injection). Trials investigating whether electrotherapy modalities were more effective than placebo or no treatment, or were an effective addition to another physical therapy intervention (e.g. manual therapy or exercise) were the main comparisons of interest. Main outcomes of interest were overall pain, function, pain on motion, patient-reported global assessment of treatment success, quality of life and the number of participants experiencing adverse events.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, extracted the data, performed a risk of bias assessment and assessed the quality of the body of evidence for the main outcomes using the GRADE approach.

MAIN RESULTS

We included 47 trials (2388 participants). Most trials (n = 43) included participants with rotator cuff disease without calcification (four trials included people with calcific tendinitis). Sixteen (34%) trials investigated the effect of an electrotherapy modality delivered in isolation. Only 23% were rated at low risk of allocation bias, and 49% were rated at low risk of both performance and detection bias (for self-reported outcomes). The trials were heterogeneous in terms of population, intervention and comparator, so none of the data could be combined in a meta-analysis.In one trial (61 participants; low quality evidence), pulsed therapeutic ultrasound (three to five times a week for six weeks) was compared with placebo (inactive ultrasound therapy) for calcific tendinitis. At six weeks, the mean reduction in overall pain with placebo was -6.3 points on a 52-point scale, and -14.9 points with ultrasound (MD -8.60 points, 95% CI -13.48 to -3.72 points; absolute risk difference 17%, 7% to 26% more). Mean improvement in function with placebo was 3.7 points on a 100-point scale, and 17.8 points with ultrasound (mean difference (MD) 14.10 points, 95% confidence interval (CI) 5.39 to 22.81 points; absolute risk difference 14%, 5% to 23% more). Ninety-one per cent (29/32) of participants reported treatment success with ultrasound compared with 52% (15/29) of participants receiving placebo (risk ratio (RR) 1.75, 95% CI 1.21 to 2.53; absolute risk difference 39%, 18% to 60% more). Mean improvement in quality of life with placebo was 0.40 points on a 10-point scale, and 2.60 points with ultrasound (MD 2.20 points, 95% CI 0.91 points to 3.49 points; absolute risk difference 22%, 9% to 35% more). Between-group differences were not important at nine months. No participant reported adverse events.Therapeutic ultrasound produced no clinically important additional benefits when combined with other physical therapy interventions (eight clinically heterogeneous trials, low quality evidence). We are uncertain whether there are differences in patient-important outcomes between ultrasound and other active interventions (manual therapy, acupuncture, glucocorticoid injection, glucocorticoid injection plus oral tolmetin sodium, or exercise) because the quality of evidence is very low. Two placebo-controlled trials reported results favouring LLLT up to three weeks (low quality evidence), however combining LLLT with other physical therapy interventions produced few additional benefits (10 clinically heterogeneous trials, low quality evidence). We are uncertain whether transcutaneous electrical nerve stimulation (TENS) is more or less effective than glucocorticoid injection with respect to pain, function, global treatment success and active range of motion because of the very low quality evidence from a single trial. In other single, small trials, no clinically important benefits of pulsed electromagnetic field therapy (PEMF), microcurrent electrical stimulation (MENS), acetic acid iontophoresis and microwave diathermy were observed (low or very low quality evidence).No adverse events of therapeutic ultrasound, LLLT, TENS or microwave diathermy were reported by any participants. Adverse events were not measured in any trials investigating the effects of PEMF, MENS or acetic acid iontophoresis.

AUTHORS' CONCLUSIONS

Based on low quality evidence, therapeutic ultrasound may have short-term benefits over placebo in people with calcific tendinitis, and LLLT may have short-term benefits over placebo in people with rotator cuff disease. Further high quality placebo-controlled trials are needed to confirm these results. In contrast, based on low quality evidence, PEMF may not provide clinically relevant benefits over placebo, and therapeutic ultrasound, LLLT and PEMF may not provide additional benefits when combined with other physical therapy interventions. We are uncertain whether TENS is superior to placebo, and whether any electrotherapy modality provides benefits over other active interventions (e.g. glucocorticoid injection) because of the very low quality of the evidence. Practitioners should communicate the uncertainty of these effects and consider other approaches or combinations of treatment. Further trials of electrotherapy modalities for rotator cuff disease should be based upon a strong rationale and consideration of whether or not they would alter the conclusions of this review.

The Role of Transcutaneous Electrical Nerve Stimulation in the Management of Temporomandibular Joint Disorder

Temporomandibular joint disorders (TMD) constitutes of a group of diseases that functionally affect the masticatory system, including the muscles of mastication and temporomandibular joint (TMJ). A number of etiologies with specific treatment have been identified, including the transcutaneous electrical nerve stimulation (TENS). The current paper presents a literature review on the use of TENS in the management of TMD patients. Temporomandibular joint disorder is very common disorder with approximately 75% of people showing some signs, while more than quarter (33%) having at least one symptom. An attempt to treat the pain should be made whenever possible. However, in cases with no defined etiology, starting with less intrusive and reversible techniques is prescribed. Transcutaneous electrical nerve stimulation is one such treatment modality, i.e. useful in the management of TMD. It comprises of controlled exposure of electrical current to the surface of skin, causing hyperactive muscles relaxation and decrease pain. Although the value of TENS to manage chronic pain in TMD patients is still controversial, its role in utilization for masticatory muscle pain is significant. However, an accurate diagnosis is essential to minimize its insufficient use. Well-controlled randomized trials are needed to determine the utilization of TENS in the management of TMD patients.

Skin impedance is not a factor in transcutaneous electrical nerve stimulation effectiveness

OBJECTIVE

Transcutaneous electrical nerve stimulation (TENS) is a nonpharmacological intervention used to manage pain using skin surface electrodes. Optimal electrode placement is unclear. We hypothesized that better analgesia would occur if electrodes were placed over sites with lower skin impedance. Optimal site selection (OSS) and sham site selection (SSS) electrode sites on the forearm were identified using a standard clinical technique.

METHODS

Experiment 1 measured skin impedance in the forearm at OSS and SSS. Experiment 2 was a crossover design double-blind randomized controlled trial comparing OSS-TENS, SSS-TENS, and placebo TENS (P-TENS) to confirm differences in skin impedance between OSS and SSS, and measure change in pressure pain threshold (PPT) following a 30-minute TENS treatment. Healthy volunteers were recruited (ten for Experiment 1 [five male, five female] and 24 for Experiment 2 [12 male, 12 female]). TENS was applied for 30 minutes at 100 Hz frequency, 100 µs pulse duration, and "strong but nonpainful" amplitude.

RESULTS

Experiment 1 results demonstrate significantly higher impedance at SSS (17.69±1.24 Ω) compared to OSS (13.53±0.57 Ω) (P=0.007). For Experiment 2, electrode site impedance was significantly higher over SSS, with both the impedance meter (P=0.001) and the TENS unit (P=0.012) compared to OSS. PPT change was significantly greater for both OSS-TENS (P=0.024) and SSS-TENS (P=0.025) when compared to P-TENS. PPT did not differ between the two active TENS treatments (P=0.81).

CONCLUSION

Skin impedance is lower at sites characterized as optimal using the described technique of electrode site selection. When TENS is applied at adequate intensities, skin impedance is not a factor in attainment of hypoalgesia of the forearm in healthy subjects. Further investigation should include testing in patients presenting with painful conditions.

Transcutaneous electrical nerve stimulation (TENS) for phantom pain and stump pain following amputation in adults

BACKGROUND

This is the first update of a Cochrane review published in Issue 5, 2010 on transcutaneous electrical nerve stimulation (TENS) for phantom pain and stump pain following amputation in adults. Pain may present in a body part that has been amputated (phantom pain) or at the site of amputation (stump pain), or both. Phantom pain and stump pain are complex and multidimensional and the underlying pathophysiology remains unclear. The condition remains a severe burden for those who are affected by it. The mainstay treatments are predominately pharmacological, with increasing acknowledgement of the need for non-drug interventions. TENS has been recommended as a treatment option but there has been no systematic review of available evidence. Hence, the effectiveness of TENS for phantom pain and stump pain is currently unknown.

OBJECTIVES

To assess the analgesic effectiveness of TENS for the treatment of phantom pain and stump pain following amputation in adults.

SEARCH METHODS

For the original version of the review we searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, PsycINFO, AMED, CINAHL, PEDRO and SPORTDiscus (February 2010). For this update, we searched the same databases for relevant randomised controlled trials (RCTs) from 2010 to 25 March 2015.

SELECTION CRITERIA

We only included RCTs investigating the use of TENS for the management of phantom pain and stump pain following an amputation in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. We planned that where available and appropriate, data from outcome measures were to be pooled and presented as an overall estimate of the effectiveness of TENS.

MAIN RESULTS

In the original review there were no RCTs that examined the effectiveness of TENS for the treatment of phantom pain and stump pain in adults. For this update, we did not identify any additional RCTs for inclusion.

AUTHORS' CONCLUSIONS

There were no RCTs to judge the effectiveness of TENS for the management of phantom pain and stump pain. The published literature on TENS for phantom pain and stump pain lacks the methodological rigour and robust reporting needed to confidently assess its effectiveness. Further RCT evidence is required before an assessment can be made. Since publication of the original version of this review, we have found no new studies and our conclusions remain unchanged.

An Investigation of the Effects of Different Pulse Patterns of Transcutaneous Electrical Nerve Stimulation (TENS) on Perceptual Embodiment of a Rubber Hand in Healthy Human Participants With Intact Limbs

OBJECTIVE

The aim of this study was to investigate the strength of perceptual embodiment achieved during an adapted version of the rubber hand illusion (RHI) in response to a series of modified transcutaneous electrical nerve stimulation (TENS) pulse patterns with dynamic temporal and spatial characteristics which are more akin to the mechanical brush stroke in the original RHI.

MATERIALS AND METHODS

A repeated-measures counterbalanced experimental study was conducted where each participant was exposed to four TENS interventions: continuous pattern TENS; burst pattern TENS (fixed frequency of 2 bursts per second of 100 pulses per second); amplitude-modulated pattern TENS (intensity increasing from zero to a preset level, then back to zero again in a cyclical fashion); and sham (no current) TENS. Participants rated the intensity of the RHI using a three-item numerical rating scale (each item was ranked from 0 to 10). Friedman's analysis of ranks (one-factor repeated measure) was used to test the differences in perceptual embodiment between TENS innervations; alpha was set at p ≤ 0.05.

RESULTS

There were statistically significant differences in the intensity of misattribution and perceptual embodiment between sham and active TENS interventions, but no significant differences between the three active TENS conditions (amplitude-modulated TENS, burst TENS, and continuous TENS). Amplitude-modulated and burst TENS produced significantly higher intensity scores for misattribution sensation and perceptual embodiment compared with sham (no current) TENS, whereas continuous TENS did not.

CONCLUSION

The findings provide tentative, but not definitive, evidence that TENS parameters with dynamic spatial and temporal characteristics may produce more intense misattribution sensations and intense perceptual embodiment than parameters with static characteristics (e.g., continuous pulse patterns).

Transcutaneous electrical nerve stimulation for acute pain

BACKGROUND

This is a second update of a Cochrane Review originally published in Issue 2, 2009. Transcutaneous Electrical Nerve Stimulation (TENS) is a non-pharmacological agent, based on delivering low voltage electrical currents to the skin. TENS is used by people to treat a variety of pain conditions.

OBJECTIVES

To assess the analgesic effectiveness of TENS, as a sole treatment, for acute pain in adults.

SEARCH METHODS

We searched the following databases up to 3 December 2014: the Cochrane Central Register of Controlled Trials (CENTRAL), in the Cochrane Library; MEDLINE; EMBASE; CINAHL; and AMED. We also checked the reference lists of included trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of adults with acute pain (< 12 weeks) if they examined TENS given as a sole treatment and assessed pain with subjective pain scales. Trials were eligible if they compared TENS to placebo TENS, no treatment controls, pharmacological interventions or non-pharmacological interventions. We excluded trials on experimental pain, case reports, clinical observations, letters, abstracts or reviews. Also we excluded trials investigating the effect of TENS on pain during childbirth (labour), primary dysmenorrhoea or dental procedures. Studies where TENS was given with another treatment as part of the formal trial design were excluded. We did not restrict any articles based on language of publication.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility and carried out study selection, data extraction, 'Risk of bias' assessment and analyses of data. We extracted data on the following: types of participants and pain condition, trial design and methods, treatment parameters, adverse effects, and outcome measures. We contacted trial authors for additional information if necessary.

MAIN RESULTS

We included 12 trials in the original review (2009) and included no further trials in the first update (2011). An additional seven new trials met the inclusion criteria in this second update. In total, we included 19 RCTs involving 1346 participants at entry, with 11 trials awaiting classification either because the full text was unavailable or information in the full text failed to clarify eligibility. We excluded most trials because TENS was given in combination with another treatment as part of the formal study design or TENS was not delivered using appropriate TENS technique. The types of acute pain included in this Cochrane Review were procedural pain, e.g. cervical laser treatment, venepuncture, screening flexible sigmoidoscopy and non-procedural pain, e.g. postpartum uterine contractions and rib fractures. We pooled data for pain intensity for six trials (seven comparisons) comparing TENS with placebo but the I(2) statistic suggested substantial heterogeneity. Mean difference (MD) with 95% confidence intervals (CIs) on a visual analogue scale (VAS, 100 mm) was -24.62 mm (95% CI -31.79 to -17.46) in favour of TENS. Data for the proportion of participants achieving ≥ 50% reduction in pain was pooled for four trials (seven comparisons) and relative risk was 3.91 (95% CI 2.42 to 6.32) in favour of TENS over placebo. We pooled data for pain intensity from five trials (seven comparisons) but the I(2) statistic suggested considerable heterogeneity. MD was -19.05 mm (95% CI -27.30 to -10.79) in favour of TENS using a random-effects model. It was not possible to pool other data. There was a high risk of bias associated with inadequate sample sizes in treatment arms and unsuccessful blinding of treatment interventions. Seven trials reported minor adverse effects, such as mild erythema and itching underneath the electrodes and participants disliking TENS sensation.

AUTHORS' CONCLUSIONS

This Cochrane Review update includes seven new trials, in addition to the 12 trials reviewed in the first update in 2011. The analysis provides tentative evidence that TENS reduces pain intensity over and above that seen with placebo (no current) TENS when administered as a stand-alone treatment for acute pain in adults. The high risk of bias associated with inadequate sample sizes in treatment arms and unsuccessful blinding of treatment interventions makes definitive conclusions impossible. There was incomplete reporting of treatment in many reports making replication of trials impossible.

Does transcutaneous electrical nerve stimulation (TENS) alleviate the pain experienced during bone marrow sampling in addition to standard techniques? A randomised, double-blinded, controlled trial

AIMS

Bone marrow aspiration and trephine (BMAT) biopsies remain important tests in haematology. However, the procedures can be moderately to severely painful despite standard methods of pain relief. To test the efficacy of transcutaneous electrical nerve stimulation (TENS) in alleviating the pain from BMAT in addition to standard analgesia using a numerical pain rating scale (NRS).

METHODS

70 patients requiring BMAT were randomised (1:1) in a double-blind, placebo-controlled trial. -35 patients received TENS impulses at a strong but comfortable amplitude (intervention group) and 35 patients received TENS impulses just above the sensory threshold (control group) (median pulse amplitude 20 and 7 mA, respectively). Patients and operators were blinded to group allocation. Pain assessments were made using a numerical pain scale completed after the procedure.

RESULTS

No significant difference in NRS pain recalled after the procedure was detected (median pain score 5.7 (95% CI 4.8 to 6.6) in control vs 5.6 (95% CI 4.8 to 6.4) in the intervention group). However, 100% of patients who had previous experience of BMAT and >94% of participants overall felt they benefited from using TENS and would recommend it to others for this procedure. There were no side effects from the TENS device, and it was well tolerated.

CONCLUSIONS

TENS is a safe, non-invasive adjunct to analgesia for reducing pain during bone marrow biopsy and provides a subjective benefit to most users; however, no objective difference in pain scores was detected when using TENS in this randomised controlled study.

CLINICAL REGISTRATION NUMBER

NCT02005354.

Application of low frequency and medium frequency currents in the management of acute and chronic pain-a narrative review

Trancutaneous electrical nerve stimulation (TENS) and interferential therapy (IFT) have been a regular line of treatment for various types of acute and chronic pain. This review aims to compile the latest literature in pain management using these modalities which use low-frequency and medium-frequency currents. The Cochrane Library, Scopus, PubMed, MEDLINE, and CINAHL were searched and studies were examined from their inception till October 2013. After title and abstract screening the relevant studies were included for this review. We found through this review that even though TENS and IFT are used in management of pain, there is limited amount of high quality research available in this area. Most of the studies lack methodological quality and have a low sample size.

Using TENS for pain control: the state of the evidence

Transcutaneous electrical nerve stimulation (TENS) is a nonpharmacological intervention that activates a complex neuronal network to reduce pain by activating descending inhibitory systems in the central nervous system to reduce hyperalgesia. The evidence for TENS efficacy is conflicting and requires not only description but also critique. Population-specific systemic reviews and meta-analyses are emerging, indicating both HF and LF TENS being shown to provide analgesia, specifically when applied at a strong, nonpainful intensity. The purpose of this article is to provide a critical review of the latest basic science and clinical evidence for TENS. Additional research is necessary to determine if TENS has effects specific to mechanical stimuli and/or beyond reduction of pain and will improve activity levels, function and quality of life.

Analgesic effects of transcutaneous electrical nerve stimulation and interferential current on experimental ischemic pain models: frequencies of 50 hz and 100 hz

[Purpose] This study compared the analgesic effects of transcutaneous electrical nerve stimulation (TENS) and interferential currents (IFC) on induced ischemic pain in healthy volunteers. [Subjects] The subjects were 36 volunteers (18 male, 18 female) without known pathology that could cause pain. Their mean age was 24.5±2.2 years. [Methods] A single-blind and parallel-group method was used. Subjects were randomly allocated to receive each 50 Hz TENS, 50 Hz IFC, 100 Hz TENS, and 100 Hz IFC. This study experimentally induced ischemic pain in otherwise pain-free subjects using a modified version of the submaximal effort tourniquet technique. Subjects completed twelve cycles of the ischemic-induced pain test. The primary outcome measure was the change in self-reported of pain intensity during one of four possible treatments. [Results] There were significant effects for Time, which were attributed to a significant reduction in pain intensity for all groups. There were no significant effects for groups or group-time interaction. The 50 Hz IFC treatment was more comfortable than the other treatments in the present study, and it is likely to be better accepted and tolerated by patients. [Conclusion] We conclude that there were no differences in the analgesic effects of the four treatments under the present experimental conditions. The 50 Hz IFC treatment is more comfortable than the other treatments.

Electrotherapy modalities for adhesive capsulitis (frozen shoulder)

BACKGROUND

Adhesive capsulitis (also termed frozen shoulder) is a common condition characterised by spontaneous onset of pain, progressive restriction of movement of the shoulder and disability that restricts activities of daily living, work and leisure. Electrotherapy modalities, which aim to reduce pain and improve function via an increase in energy (electrical, sound, light, thermal) into the body, are often delivered as components of a physical therapy intervention. This review is one in a series of reviews which form an update of the Cochrane review 'Physiotherapy interventions for shoulder pain'.

OBJECTIVES

To synthesise the available evidence regarding the benefits and harms of electrotherapy modalities, delivered alone or in combination with other interventions, for the treatment of adhesive capsulitis.

SEARCH METHODS

We searched CENTRAL, MEDLINE, EMBASE, CINAHL Plus and the ClinicalTrials.gov and World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) clinical trials registries up to May 2014, unrestricted by language, and reviewed the reference lists of review articles and retrieved trials to identify any other potentially relevant trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and controlled clinical trials using a quasi-randomised method of allocation that included adults with adhesive capsulitis and compared any electrotherapy modality to placebo, no treatment, a different electrotherapy modality, or any other intervention. The two main questions of the review focused on whether electrotherapy modalities are effective compared to placebo or no treatment, or if they are an effective adjunct to manual therapy or exercise (or both). The main outcomes of interest were participant-reported pain relief of 30% or greater, overall pain, function, global assessment of treatment success, active shoulder abduction, quality of life, and the number of participants experiencing any adverse event.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, extracted the data, performed a risk of bias assessment, and assessed the quality of the body of evidence for the main outcomes using the GRADE approach.

MAIN RESULTS

Nineteen trials (1249 participants) were included in the review. Four trials reported using an adequate method of allocation concealment and six trials blinded participants and personnel. Only two electrotherapy modalities (low-level laser therapy (LLLT) and pulsed electromagnetic field therapy (PEMF)) have been compared to placebo. No trial has compared an electrotherapy modality plus manual therapy and exercise to manual therapy and exercise alone. The two main questions of the review were investigated in nine trials.Low quality evidence from one trial (40 participants) indicated that LLLT for six days may result in improvement at six days. Eighty per cent (16/20) of participants reported treatment success with LLLT compared with 10% (2/20) of participants receiving placebo (risk ratio (RR) 8.00, 95% confidence interval (CI) 2.11 to 30.34; absolute risk difference 70%, 95% CI 48% to 92%). No participants in either group reported adverse events.We were uncertain whether PEMF for two weeks improved pain or function more than placebo at two weeks because of the very low quality evidence from one trial (32 participants). Seventy-five per cent (15/20) of participants reported pain relief of 30% or more with PEMF compared with 0% (0/12) of participants receiving placebo (RR 19.19, 95% CI 1.25 to 294.21; absolute risk difference 75%, 95% CI 53% to 97%). Fifty-five per cent (11/20) of participants reported total recovery of joint function with PEMF compared with 0% (0/12) of participants receiving placebo (RR 14.24, 95% CI 0.91 to 221.75; absolute risk difference 55%, 95% CI 31 to 79).Moderate quality evidence from one trial (63 participants) indicated that LLLT plus exercise for eight weeks probably results in greater improvement when measured at the fourth week of treatment, but a similar number of adverse events, compared with placebo plus exercise. The mean pain score at four weeks was 51 points with placebo plus exercise, while with LLLT plus exercise the mean pain score was 32 points on a 100 point scale (mean difference (MD) 19 points, 95% CI 15 to 23; absolute risk difference 19%, 95% CI 15% to 23%). The mean function impairment score was 48 points with placebo plus exercise, while with LLLT plus exercise the mean function impairment score was 36 points on a 100 point scale (MD 12 points, 95% CI 6 to 18; absolute risk difference 12%, 95% CI 6 to 18). Mean active abduction was 70 degrees with placebo plus exercise, while with LLLT plus exercise mean active abduction was 79 degrees (MD 9 degrees, 95% CI 2 to 16; absolute risk difference 5%, 95% CI 1% to 9%). No participants in either group reported adverse events. LLLT's benefits on function were maintained at four months.Based on very low quality evidence from six trials, we were uncertain whether therapeutic ultrasound, PEMF, continuous short wave diathermy, Iodex phonophoresis, a combination of Iodex iontophoresis with continuous short wave diathermy, or a combination of therapeutic ultrasound with transcutaneous electrical nerve stimulation (TENS) were effective adjuncts to exercise. Based on low or very low quality evidence from 12 trials, we were uncertain whether a diverse range of electrotherapy modalities (delivered alone or in combination with manual therapy, exercise, or other active interventions) were more or less effective than other active interventions (for example glucocorticoid injection).

AUTHORS' CONCLUSIONS

Based upon low quality evidence from one trial, LLLT for six days may be more effective than placebo in terms of global treatment success at six days. Based upon moderate quality evidence from one trial, LLLT plus exercise for eight weeks may be more effective than exercise alone in terms of pain up to four weeks, and function up to four months. It is unclear whether PEMF is more or less effective than placebo, or whether other electrotherapy modalities are an effective adjunct to exercise. Further high quality randomised controlled trials are needed to establish the benefits and harms of physical therapy interventions (that comprise electrotherapy modalities, manual therapy and exercise, and are reflective of clinical practice) compared to interventions with evidence of benefit (for example glucocorticoid injection or arthrographic joint distension).

Role of transcutaneous electrical nerve stimulation in post-operative analgesia

The use of transcutaneous electrical nerve stimulation (TENS) as non-pharmacological therapeutic modality is increasing. The types of TENS used clinically are conventional TENS, acupuncture TENS and intense TENS. Their working is believed to be based on gate control theory of pain and activation of endogenous opioids. TENS has been used in anaesthesia for treatment of post-operative analgesia, post-operative nausea vomiting and labour analgesia. Evidence to support analgesic efficacy of TENS is ambiguous. A systematic search of literature on PubMed and Cochrane Library from July 2012 to January 2014 identified a total of eight clinical trials investigating post-operative analgesic effects of TENS including a total of 442 patients. Most of the studies have demonstrated clinically significant reduction in pain intensity and supplemental analgesic requirement. However, these trials vary in TENS parameters used that is, duration, intensity, frequency of stimulation and location of electrodes. Further studies with adequate sample size and good methodological design are warranted to establish general recommendation for use of TENS for post-operative pain.

Role of rehabilitation medicine and physical agents in the treatment of cancer-associated pain

PURPOSE

To provide an overview of rehabilitation medicine- and physical modality-based approaches to cancer pain management, and to highlight the fact that these approaches are generally used in conjunction and that a majority are focused on minimizing pain during periods of mobility and the performance of activities of daily living.

METHODS

We performed a nonsystematic literature review and provide a description of the current standard of care.

RESULTS

Rehabilitative and physical modalities used to manage pain can be grouped into four categories: those that modulate nociception, stabilize or unload painful structures, influence physiological processes that indirectly influence nociception, or alleviate pain arising from the overloading of muscles and connective tissues that often occurs after surgery or with sarcopenia in late-stage cancer. Most modalities have been pragmatically refined over the years, and many have an evidence base, although few have been explicitly validated in the oncologic setting. With few exceptions, they are patient controlled and free of adverse effects.

CONCLUSION

Physical modalities and rehabilitation medicine offer a range of pain management approaches that may serve as beneficial adjuncts to the conventional systemic and interventional analgesic strategies used to control cancer-related pain. These approaches may be particularly beneficial to patients with movement-associated pain and those who are ambivalent regarding pharmacoanalgesia.

Can Extracorporeal Magnetic Innervation Be a Treatment Modality for Primary Dysmenorrhea

<b><i>Background/Aims:</i></b> To evaluate the efficacy of extracorporeal magnetic innervation (ExMI) as a treatment for primary dysmenorrhea compared with nonsteroidal anti-inflammatory drugs (NSAIDs) and combined oral contraceptives (COCs). <b><i>Methods:</i></b> The cases were randomized into three groups (NSAID = 51, ExMI = 53, COC = 54). ExMI was applied for a total of 10 sessions. Women in the NSAID group used an oral NSAID at the start of each menstruation. Women in the COC group were given combined pills. Of the treatment options, ExMI was applied for only a single period, whereas NSAID and COC use continued for 12 months. <b><i>Results:</i></b> At the first menstruation, visual analog scale (VAS) scores improved significantly in all groups (p < 0.001). NSAIDs and COCs continued to show efficacy over the entire study period (p < 0.05). However, in the ExMI group, VAS values increased from the first menstruation until 12 months. The VAS score at the 12th month was significantly higher in the ExMI group than in the other groups (p < 0.05), but markedly lower than the pretreatment value (49.9 ± 8.3 vs. 71.1 ± 10.1, p < 0.001). <b><i>Conclusions:</i></b> ExMI therapy might be a promising novel noninvasive option for primary dysmenorrhea. Efficacy began to decline after 3 months, but continued for 12 months.

Neuromodulation of chronic headaches: position statement from the European Headache Federation

The medical treatment of patients with chronic primary headache syndromes (chronic migraine, chronic tension-type headache, chronic cluster headache, hemicrania continua) is challenging as serious side effects frequently complicate the course of medical treatment and some patients may be even medically intractable. When a definitive lack of responsiveness to conservative treatments is ascertained and medication overuse headache is excluded, neuromodulation options can be considered in selected cases. Here, the various invasive and non-invasive approaches, such as hypothalamic deep brain stimulation, occipital nerve stimulation, stimulation of sphenopalatine ganglion, cervical spinal cord stimulation, vagus nerve stimulation, transcranial direct current stimulation, repetitive transcranial magnetic stimulation, and transcutaneous electrical nerve stimulation are extensively published although proper RCT-based evidence is limited. The European Headache Federation herewith provides a consensus statement on the clinical use of neuromodulation in headache, based on theoretical background, clinical data, and side effect of each method. This international consensus further gives recommendations for future studies on these new approaches. In spite of a growing field of stimulation devices in headaches treatment, further controlled studies to validate, strengthen and disseminate the use of neurostimulation are clearly warranted. Consequently, until these data are available any neurostimulation device should only be used in patients with medically intractable syndromes from tertiary headache centers either as part of a valid study or have shown to be effective in such controlled studies with an acceptable side effect profile.

What makes transcutaneous electrical nerve stimulation work? Making sense of the mixed results in the clinical literature

Transcutaneous electrical nerve stimulation (TENS) is a nonpharmacological treatment for control of pain. It has come under much scrutiny lately with the Center for Medicare Services rendering a recent decision stating that "TENS is not reasonable and necessary for the treatment of CLBP [chronic low back pain]." When reading and analyzing the existing literature for which systematic reviews show that TENS is inconclusive or ineffective, it is clear that a number of variables related to TENS application have not been considered. Although many of the trials were designed with the highest of standards, recent evidence suggests that factors related to TENS application need to be considered in an assessment of efficacy. These factors include dosing of TENS, negative interactions with long-term opioid use, the population and outcome assessed, timing of outcome measurement, and comparison groups. The purpose of this perspective is to highlight and interpret recent evidence to help improve the design of clinical trials and the efficacy of TENS in the clinical setting.

Transcutaneous electric nerve stimulation (TENS) for cancer pain in adults

BACKGROUND

Cancer-related pain is complex and multi-dimensional but the mainstay of cancer pain management has predominantly used a biomedical approach. There is a need for non-pharmacological and innovative approaches. Transcutaneous Electric Nerve Stimulation (TENS) may have a role in pain management but the effectiveness of TENS is currently unknown. This is an update of the original review published in Issue 3, 2008.

OBJECTIVES

The aim of this systematic review was to determine the effectiveness of TENS for cancer-related pain in adults.

SEARCH METHODS

The initial review searched The Cochrane Library, MEDLINE, EMBASE, CINAHL, PsychINFO, AMED and PEDRO databases in April 2008. We performed an updated search of CENTRAL, MEDLINE, EMBASE, CINAHL and PEDRO databases in November 2011.

SELECTION CRITERIA

We included only randomised controlled trials (RCTS) investigating the use of TENS for the management of cancer-related pain in adults.

DATA COLLECTION AND ANALYSIS

The search strategy identified a further two studies for possible inclusion. One of the review authors screened each abstract using a study eligibility tool. Where eligibility could not be determined, a second author assessed the full paper. One author used a standardised data extraction sheet to collect information on the studies and independently assess the quality of the studies using the validated five-point Oxford Quality Scale. The small sample sizes and differences in patient study populations of the three included studies (two from the original review and a third included in this update) prevented meta-analysis. For the original review the search strategy identified 37 possible published studies; we divided these between two pairs of review authors who decided on study selection; all four review authors discussed and agreed final scores.

MAIN RESULTS

Only one additional RCT met the eligibility criteria (24 participants) for this updated review. Although this was a feasibility study, not designed to investigate intervention effect, it suggested that TENS may improve bone pain on movement in a cancer population. The initial review identified two RCTs (64 participants) therefore this review now includes a total of three RCTs (88 participants). These studies were heterogenous with respect to study population, sample size, study design, methodological quality, mode of TENS, treatment duration, method of administration and outcome measures used. In one RCT, there were no significant differences between TENS and placebo in women with chronic pain secondary to breast cancer treatment. In the other RCT, there were no significant differences between acupuncture-type TENS and sham in palliative care patients; this study was underpowered.

AUTHORS' CONCLUSIONS

Despite the one additional RCT, the results of this updated systematic review remain inconclusive due to a lack of suitable RCTs. Large multi-centre RCTs are required to assess the value of TENS in the management of cancer-related pain in adults.

Transcutaneous electric nerve stimulation (TENS) for cancer pain in adults

BACKGROUND

Cancer-related pain is complex and multi-dimensional but the mainstay of cancer pain management has predominantly used a biomedical approach. There is a need for non-pharmacological and innovative approaches. Transcutaneous Electric Nerve Stimulation (TENS) may have a role in pain management but the effectiveness of TENS is currently unknown. This is an update of the original review published in Issue 3, 2008.

OBJECTIVES

The aim of this systematic review was to determine the effectiveness of TENS for cancer-related pain in adults.

SEARCH METHODS

The initial review searched The Cochrane Library, MEDLINE, EMBASE, CINAHL, PsychINFO, AMED and PEDRO databases in April 2008. We performed an updated search of CENTRAL, MEDLINE, EMBASE, CINAHL and PEDRO databases in November 2011.

SELECTION CRITERIA

We included only randomised controlled trials (RCTS) investigating the use of TENS for the management of cancer-related pain in adults.

DATA COLLECTION AND ANALYSIS

The search strategy identified a further two studies for possible inclusion. One of the review authors screened each abstract using a study eligibility tool. Where eligibility could not be determined, a second author assessed the full paper. One author used a standardised data extraction sheet to collect information on the studies and independently assess the quality of the studies using the validated five-point Oxford Quality Scale. The small sample sizes and differences in patient study populations of the three included studies (two from the original review and a third included in this update) prevented meta-analysis. For the original review the search strategy identified 37 possible published studies; we divided these between two pairs of review authors who decided on study selection; all four review authors discussed and agreed final scores.

MAIN RESULTS

Only one additional RCT met the eligibility criteria (24 participants) for this updated review. Although this was a feasibility study, not designed to investigate intervention effect, it suggested that TENS may improve bone pain on movement in a cancer population. The initial review identified two RCTs (64 participants) therefore this review now includes a total of three RCTs (88 participants). These studies were heterogenous with respect to study population, sample size, study design, methodological quality, mode of TENS, treatment duration, method of administration and outcome measures used. In one RCT, there were no significant differences between TENS and placebo in women with chronic pain secondary to breast cancer treatment. In the other RCT, there were no significant differences between acupuncture-type TENS and sham in palliative care patients; this study was underpowered.

AUTHORS' CONCLUSIONS

Despite the one additional RCT, the results of this updated systematic review remain inconclusive due to a lack of suitable RCTs. Large multi-centre RCTs are required to assess the value of TENS in the management of cancer-related pain in adults.

Therapeutic modalities--an updated review for the hand surgeon

The number of therapeutic modalities available to the hand surgeon has greatly increased over the past several decades. A field once predicated only on heat, massage, and cold therapy now uses electrical stimulators, ultrasound, biofeedback, iontophoresis, phonophoresis, mirror therapy, lasers, and a number of other modalities. With this expansion in choices, there has been a concurrent effort to better define which modalities are truly effective. In this review, we aim to characterize the commonly used modalities and provide the evidence available that supports their continued use.

Assessing the effects of transcutaneous electrical nerve stimulation (TENS) in post-thoracotomy analgesia

BACKGROUND AND OBJECTIVES

Transcutaneous electrical nerve stimulation (TENS) is commonly used to treat musculoskeletal pain, but it may also be indicated for postoperative analgesia. The objective of this study was to evaluate the analgesic effects of TENS on post-thoracotomy.

METHODS

Thirty patients between 18 and 60 years of age undergoing thoracotomy for lung cancer resection on the second postoperative day were included in this study. Patients were divided into two groups (G1 and G2). G1 patients were treated with TENS; and in G2 (without TENS) electrodes were placed but the equipment was not turned on. TENS was maintained for one hour. The visual analogue scale was used to evaluate the analgesic effects on three moments: before TENS (M0), immediately after TENS (M1), and one hour later (M2), with the patient at rest, elevation of the upper limbs, change in decubitus, and coughing.

RESULTS

The intensity of pain at rest was higher in G2 immediately after TENS, but not one hour after the procedure. There was no difference between both groups with elevation of the upper limbs, decubitus change, and coughing.

CONCLUSIONS

With the use of TENS for one hour on the second post-thoracotomy day in patients who received fentanyl (50 μg) associated with bupivacaine (5 mL), a reduction in pain intensity was observed at rest immediately after TENS; with elevation of the upper limbs, change in decubitus, and coughing, a reduction in pain severity was not observed.

Analgesia for amniocentesis or chorionic villus sampling

BACKGROUND

Besides risks of miscarriage, pregnant women undergoing amniocentesis or chorionic villus sampling (CVS) are also concerned about pain associated with these procedures. Currently, approaches to analgesia can be categorised in two broad categories - non-pharmacological and pharmacological agents.

OBJECTIVES

To evaluate whether different methods of analgesia have any impact on pain reduction during amniocentesis or chorionic villus sampling (CVS).

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 August 2011).

SELECTION CRITERIA

All randomised trials comparing different method of analgesia for amniocentesis or CVS. We also include trials with quasi-randomised designs, but analyse and report their results separately.

DATA COLLECTION AND ANALYSIS

Both review authors assessed eligibility and trial quality and performed data extraction.

MAIN RESULTS

We included a total of five randomised studies (involving 805 women) evaluating different methods of analgesia for amniocentesis; there were no studies in women undergoing CVS.One RCT (N = 203) and one quasi-randomised study (N = 220) compared infiltrative local anaesthesia with no anaesthesia and found no statistical difference in experienced pain on the visual analogue scale (VAS) (mean differences (MD) -2.50 and 1.20; 95% confidence interval (CI) -6.98 to 1.98 and -2.67 to 5.07).One study (N = 200) compared light leg rubbing versus no intervention during amniocentesis and found no change in experienced anxiety (MD 0.2; 95% CI -0.63 to 1.03) or VAS pain score (MD 0.3; 95% CI -0.35 to 0.95) during amniocentesis.Another study with 62 patients did not find any benefit of using subfreezing temperature needle during amniocentesis in terms of decreased VAS pain score (MD -0.8; 95% CI -1.8 to 0.2). In addition, there was no difference between anticipated and actual pain (MD 0.4; 95% CI -0.82 to 1.62) (before/after comparison).There was also no difference in VAS pain scores in the study with 120 participants comparing lidocaine-prilocaine analgesic cream to placebo cream before amniocentesis (MD -0.6; 95% CI -1.44 to 0.24).

AUTHORS' CONCLUSIONS

In general, women who undergo amniocentesis could be informed that pain during procedure is minor and that there is currently insufficient evidence to support the use of local anaesthetics, leg rubbing or subfreezing the needle for pain reduction during procedure.