Conventional Transcutaneous Electrical Nerve Stimulation Research Articles

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

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

Effectiveness of Transcutaneous Electrical Nerve Stimulation on Pain and Disability Among Patients with Hip Arthroplasty: A Randomized Control Study

Background: Pain after surgery is highly inevitable, and the use of nonsteroidal anti-inflammatory drugs (NSAIDs) has been reported with side effects. Objectives: This study evaluated the effectiveness of transcutaneous electrical nerve stimulation (TENS) on pain intensity and disability of patients who underwent hip arthroplasty. Methods: A purposive sampling technique was used to recruit 56 subjects that underwent hip arthroplasty. They were randomly allocated to the TENS group (TG) and control group (CG) equally. The subjects in the TG group were treated with conventional TENS twice a day for three weeks, but the CG group was treated with normal drugs only. Pain intensity and hip disability were measured in both groups with the Visual Analogue scale (VAS) and Oxford hip score before the treatment and after the intervention, respectively. Results: The results showed that there was a significant reduction between the pre-treatment and post-treatment pain intensity (t = 3.83, P = 0.003) and hip disability (t = -4.45, P < 0.001) in the TG group. A significant reduction was also observed in pain intensity (t = 3.16, P = 0.01) and hip disability (t = -6.71, P = 0.000) between the pre-treatment and post-treatment periods in the CG group. There was a significant reduction in post-treatment pain intensity (t = 10, P = 0.000) and hip disability (t = -3.51, P = 0.006) when the TG group was compared with the CG group. Conclusions: TENS was effective in the management of acute post-surgical pain and disability of patients with hip arthroplasty.

Modulation of Corticospinal Excitability by Two Different Somatosensory Stimulation Patterns; A Pilot Study.

Following amputation, almost two-thirds of amputees experience unpleasant to painful sensations in the area of the missing limb. Whereas the mechanism of phantom limb pain (PLP) remains unknown, it has been shown that maladaptive cortical plasticity plays a major role in PLP. Transcutaneous electrical nerve stimulation (TENS) generating sensory input is believed to be beneficial for PLP relief. TENS effect may be caused by possible reversing reorganization at the cortical level that can be evaluated by changes in the excitability of the corticospinal (CS) pathway. Excitability changes are dependent on the chosen stimulation patterns and parameters. The aim of this study was to investigate the effect of two TENS patterns on the excitability of the CS tract among healthy subjects. We compared a non-modulated TENS as a conventional pattern with pulse width modulated TENS pattern. Motor evoked potentials (MEPs) from APB muscles of stimulated arm (TENS-APB) and contralateral arm (Control-APB) were recorded. We applied single TMS pulses on two subjects for each TENS pattern. The results showed that both patterns increase the CS excitability, while the effects of the conventional TENS is stronger. However, the amplitude of MEPs from control-APB after TENS delivery remained almost the same.Clinical Relevance- The primary results revealed changes in the activity of CS pathway for both patterns. A future study on a larger population is needed to provide strong evidence on the changes in CS excitability. The evaluation part with more factors such as changes in intracortical inhibition (ICI) may be beneficial to find an optimal modulated TENS pattern to enhance pain alleviation process in PLP.

A comparison of application frequency of physical therapy modalities in patients with chronic mechanical low back pain.

This study aims to evaluate the effects of physical therapy modalities five days a week versus twice a week with a three-day interval on pain, depression, and functional disability in patients with chronic mechanical low back pain. Between June 2018 and November 2018, a total of 60 patients (39 females, 21 males; mean age 41.0±6.8 years; range, 25 to 55 years) with chronic mechanical low back pain were included. The patients were divided into two groups: Group 1 (n=30) received physical therapy five days a week for a total of 15 sessions, while Group 2 (n=30) received physical therapy twice a week with a three-day interval for a total of six sessions. Per protocol, all patients were applied hot pack for 20 min, followed by conventional transcutaneous electrical nerve stimulation (TENS) for 20 min and therapeutic ultrasound (US) for 10 min in each session. All patients were given exercise training and were instructed to do twice a day up to four weeks after the completion of physical therapy sessions. The severity of low back pain was evaluated using the visual analog scale (VAS), the severity of depression using the Beck Depression Inventory (BDI), and functional disability using the Oswestry Disability Index (ODI). All patients were evaluated before and after physical therapy and at four weeks. The results were compared between the groups. There was no statistically significant difference in the age, gender, body mass index, occupation, VAS, BDI, and ODI scores at the time of randomization (p>0.05). Intra-group analysis showed a significant improvement in all parameters after physical therapy compared to pre-treatment values and at four weeks compared to the post-treatment values (p<0.001). The differences of changes were used for the inter- group analysis which revealed a difference of change in favor of improvement was significantly higher in Group 2 than Group 1 (p<0.001). There was no significant difference between the post-treatment values and values at four weeks (p>0.05). Our study results suggest that both physical therapy modalities applied five days week and twice a week are effective in pain, depression, and functional disability. However, physical therapy protocol applied twice a week yields more improvement, indicating that it is more advantageous with less cost and lost workdays.

How does cross-education affects muscles of paretic upper extremity in subacute stroke survivors?

This study aimed to evaluate the benefits of adding electromuscular stimulation (EMS) to the flexors of wrist muscles on the nonparetic limb in conventional stroke training to strengthen homologous agonist and antagonist muscles on the paretic side in patients with subacute stroke. The EMS group patients (n = 15) received conventional therapy for 30 sessions for 6weeks (60min/session) with 30min of electrical stimulation to their nonparetic forearm using wrist flexors, with 5min of pre- and post-warm-up. The transcutaneous electrical nerve stimulation (TENS) group patients (n = 15) received the same conventional rehabilitation training with 30min of conventional antalgic TENS at a barely sensible level to their nonparetic forearm. The Fugl-Meyer motor function assessment for upper extremity (FMA-UE), functional independence measure (FIM), Brunnstrom staging of recovery for hand, maximum and mean wrist flexion force (flexionmax and flexionmean), and wrist extension force (extensionmax and extensionmean) of paretic untrained limb were evaluated before and after the treatment. EMS and TENS group patients improved similarly in terms of FMA-UE, FIM, and Brunnstrom staging for hand recovery. However, flexionmax and flexionmean of the paretic limb increased more in the EMS group than in the TENS group. Extensionmax and extensionmean on the paretic side increased in the EMS group but did not differ in the TENS group. Cross-education via EMS may have a beneficial effect as an adjunct to conventional treatment methods. This study is retrospectively registered and is available at www.clinicaltrials.gov (ID: NCT04113369).

An Efficient Noninvasive Neuromodulation Modality for Overactive Bladder Using Time Interfering Current Method.

The present study aimed to evaluate a new tibial nerve stimulation (TNS) modality, which uses interferential currents, in terms of the stimulation electric field penetration efficiency into the body and physiological effectiveness. In silico experiments were performed to analyze the penetration efficiency of proposed interferential current therapy (ICT). Based on this, we performed in vivo experiments to measure excitation threshold of ICT for the tibial nerve, which is related to stimulation field near the nerve. Regarding analysis of the physiological effectiveness, in vivo ICT-TNS was performed, and changes in bladder contraction frequency and voiding volume were measured. The penetration efficiency and physiological effectiveness of ICT were evaluated by comparison with those of conventional TNS using transcutaneous electrical nerve stimulation (TENS). Simulation results showed that ICT has high penetration efficiency, thereby generating stronger field than TENS. These results are consistent with the in vivo results that nerve excitation threshold of ICT is lower than that of TENS. Moreover, ICT-TNS decreased contraction frequency and increased voiding volume, and its performance was profound compared with that of TENS-TNS. The proposed ICT is more efficient in inducing the stimulation field near the tibial nerve placed deep inside the body compared with conventional TENS and shows a good clinical effectiveness for TNS. The high efficiency of ICT increases the safety of noninvasive neurostimulation; therefore, it has clinical potential to become a promising modality for TNS to treat OAB and other peripheral neurostimulations.

Different Transcutaneous Electrical Nerve Stimulation Modes in Relieving Chronic Pudendal Neuralgia in Females

Purpose: to evaluate and compare the effects of two different transcutaneous electrical nerve stimulation (TENS) modes (conventional and SLR acupuncture-like TENS) on the female pudendal neuralgia. Methods: Thirty female patients suffering from chronic pudendal neuralgia from out-clinic of the gynecological and obstetrical department, OM-EL MISRIEEN hospital, were participated in this study. Their ages ranged from 30 to 40 years old. They were assigned randomly into two equal groups; group (A) received the conventional TENS, group (B) received the SLR Acupuncture-likeTENS, in addition to the traditional physical therapy and medical care for both groups, duration of treatment was 20 minutes/session, every other day for 3 months. Measurement of the serum cortisol level (SCL) and the visual analogue scale (VAS) were recorded before and at the end of intervention. Results: Results showed that both TENS modes were effective in improving the pudendal neuralgia as manifested by significant decreased SCL and VAS (P<0.05) at pre and post treatment program. Conclusion: SLR acupuncture-like TENS more effective than the conventional TENS in improving the female pudendal neuralgia.

Transcutaneous electrical nerve stimulation (TENS) for chronic neck pain.

Chronic neck pain is a highly prevalent condition, affecting 10% to 24% of the general population. Transcutaneous electrical nerve stimulation (TENS) is the noninvasive, transcutaneous use of electrical stimulation to produce analgesia. It is a simple, low-cost and safe intervention used in clinical practice as an adjunct treatment for painful musculoskeletal conditions that have a considerable impact on daily activities, such as chronic neck pain. This review is a split from a Cochrane Review on electrotherapy for neck pain, published in 2013, and focuses specifically on TENS for chronic neck pain. To evaluate the effectiveness of transcutaneous electrical nerve stimulation (TENS) (alone or in association with other interventions) compared with sham and other clinical interventions for the treatment of chronic neck pain. We searched Cochrane Back and Neck Trials Register, CENTRAL, MEDLINE, Embase, five other databases and two trials registers to 9 November 2018. We also screened the reference lists of relevant studies to identify additional trials. There were no language, source, or publication date restrictions. We included randomised controlled trials (RCTs) involving adults (≥ 18 years of age) with chronic neck pain (lasting > 12 weeks) that compared TENS alone or in combination with other treatments versus active or inactive treatments. The primary outcomes were pain, disability and adverse events. Two independent review authors selected the trials, extracted data and assessed the risk of bias of included studies. A third review author was consulted in case of disagreements. We used the Cochrane 'Risk of bias' tool (adapted by Cochrane Back and Neck), to assess the risk of bias of individual trials and GRADE to assess the certainty of evidence. We used risk ratios (RRs) to measure treatment effects for dichotomous outcomes, and mean differences (MDs) for continuous outcomes, with their respective 95% confidence intervals (CIs). We included seven RCTs with a total of 651 participants, mean age 31.7 to 55.5 years, conducted in three different countries (Turkey, Jordan and China). The length of follow-up ranged from one week to six months. Most RCTs used continuous TENS, with a frequency of 60 Hz to 100 Hz, pulse width of 40 μs to 250 μs and tolerable intensity, described as a tingling sensation without contraction, in daily sessions lasting 20 to 60 minutes. Due to heterogeneity in interventions and outcomes, we did not pool individual study data into meta-analyses. Overall, we judged most studies as being at low risk for selection bias and high risk for performance and detection bias. Based on the GRADE approach, there was very low-certainty evidence from two trials about the effects of conventional TENS when compared to sham TENS at short-term (up to 3 months after treatment) follow-up, on pain (assessed by the Visual Analogue Scale (VAS)) (MD -0.10, 95% CI -0.97 to 0.77) and the percentage of participants presenting improvement of pain (RR 1.57, 95% CI 0.84 to 2.92). None of the included studies reported on disability or adverse events. This review found very low-certainty evidence of a difference between TENS compared to sham TENS on reducing neck pain; therefore, we are unsure about the effect estimate. At present, there is insufficient evidence regarding the use of TENS in patients with chronic neck pain. Additional well-designed, -conducted and -reported RCTs are needed to reach robust conclusions.

Efficacy of transcutaneous electrical nerve stimulation combined with therapeutic exercise on hand function in children with hemiplegic cerebral palsy

Purpose: Transcutaneous electrical nerve stimulation (TENS) is a nonpharmacological method used to reduce spasticity. It was also assumed that TENS reduces pain and therefore improves limb function. Most of the previous studies about the effect of TENS were done in the lower limb and in stroke patients. There is a lack of enough literature about the direct and indirect effects of TENS in the upper limb. Hence, our study aimed to determine whether TENS combined with therapeutic exercises helps to improves hand function by reducing spasticity in children with hemiplegic cerebral palsy (CP).Materials and methods: Twenty-nine children with hemiplegic CP were randomly assigned to the TENS group (n = 15) or the control group (n = 14). The TENS group received traditional physical therapy with the adjunct application of conventional TENS for 30 minutes (pulse duration, 250 µs; pulse rate, 100 Hz) on the wrist extensors, once daily, 3 days a week, for 8 weeks, while the control group received traditional physical therapy.Results: The results showed a significant intergroup difference in handgrip strength over the 8-week period. The time to accomplish the Jebsen Taylor Hand Function Test (JTHFT) task decreased by 48% and the ABILHAND-Kids questionnaire scores improved by 23% in the TENS group.Conclusions: The use of TENS in combination with therapeutic exercise may improve strength and hand function.

Comparative analysis between three forms of application of transcutaneous electrical nerve stimulation and its effect in college students with non-specific low back pain

ABSTRACT BACKGROUND AND OBJECTIVES: There are a variety of ways to apply the transcutaneous electrical nerve stimulation (TENS) without an established way that provides better results in the treatment of nonspecific low back pain. The objective of this study was to evaluate which application of TENS has a better effect on the immediate reduction of the intensity of spontaneous and provoked pain in college students with nonspecific low back pain. METHODS: Quantitative, randomized and cross-sectional study. Twenty young individuals were divided into four groups and received a different intervention per week, totaling four weeks. The groups were Conventional TENS with the frequency of 100Hz, a pulse duration of 200µs; TENS with frequency and intensity variation with frequency variation and automatic pulse duration, TENS Burst with frequency modulated at 2Hz, pulse duration of 250µs; and placebo in which the subjects underwent a pacing protocol with no tingling sensation or muscle contraction. All sessions had a total application time of 20 minutes. They were evaluated for spontaneous pain through the application of the visual analog scale (VAS), and pain provoked by the algometer and cold pain through the application of solid ice directly to the skin, and VAS for the intensity of cold pain, all performed before and after each application of the electrotherapy. RESULTS: Only the visual analog scale of spontaneous pain showed significant results (p<0.05) when compared intragroups, in the three applied currents. CONCLUSION: The three forms used in the present study were able to reduce spontaneous pain after the intervention by electrostimulation.

Where do the electrodes go? The clinical use of TENS

Transcutaneous electrical nerve stimulation (TENS) is an adjunct modality that can be used to help alleviate pain in our animal patients. It is a modality that is low in side effects and cost, making it an easy choice to add to the rehabilitation plan. This article describes conventional TENS and its clinical application.

The effects of balance and postural stability exercises on spa based rehabilitation programme in patients with ankylosing spondylitis.

Ankylosing spondylitis (AS) can cause severe functional disorders that lead to loss of balance. The aim of this study was to investigate the effects of balance and postural stability exercises on spa based rehabilitation programme in AS subjects. Twenty-one participants were randomized to the study (n= 11) and control groups (n= 10). Patients balance and stability were assessed with the Berg Balance Scale (BBS), Timed Up and Go (TUG) Test, Single Leg Stance Test (SLST) and Functional Reach Test (FRT). AS spesicied measures were used for assessing to other parameters. The treatment plan for both groups consisted of conventional transcutaneous electrical nerve stimulation (TENS), spa and land-based exercises 5 days per week for 3 weeks. The study group performed exercises based on postural stability and balance with routine physiotherapy practice in thermal water and in exercise room. The TUG, SLST and FUT scores were significantly increased in the study group. In both groups, the BASMI, BASFI, BASDAI and ASQoL scores decreased significantly by the end of the treatment period (p< 0.05). In AS rehabilitation, performing balance and stability exercises in addition to spa based routine approaches can increase the duration of maintaining balance and can improve the benefits of physiotherapy.

Effect of the Conventional Transcutaneous Electrical Nerve Stimulation on Heart Rhythm

Effect of the Conventional Transcutaneous Electrical Nerve Stimulation on Heart Rhythm

Effects of Low-Level Laser Therapy and Transcutaneous Electrical Nerve Stimulation on Pain and Hand Function Following Carpal Tunnel Syndrome

Introduction: This study aimed to compare the short-term effects of Low-Level Laser Therapy (LLLT) and Transcutaneous Electrical Nerve Stimulation (TENS) on hand pain and function in patients with low or moderate levels of Carpal Tunnel Syndrome (CTS). Materials and Methods : Twenty-four patients with confirmed mild to moderate CTS were recruited for this study. The eligible patients were randomly divided into two groups: LLLT and TENS. Patients in the LLLT group were exposed to GaAlAs diode laser, 808 nm with 6.5 J/cm 2 for two points perpendicularly over the carpal area. Patients in the TENS group were treated daily by conventional TENS with 80 µs duration for a period of 30 minutes per day. All patients were treated daily, five days per week for a period of two weeks. The researchers performed clinical assessment using visual analogue scale and McGill Pain questionnaire for pain rating and Disabilities of the Arm, Shoulder and Hand questionnaire for functional scales. For statistical analysis, paired t-test was used in each group, and analysis of variance was used for comparison between groups. Results: All outcome measures in the LLLT group were substantially improved while the TENS group provided better pain sensation. Conclusion: This study documented that LLLT might be effective in reducing pain and improving function in patients with mild to moderate CTS. Electrical stimulation might have been effective (short term) in controlling pain in these patients. Keywords: Carpal Tunnel Syndrome; Function; Low-level Lasers; Pain; TENS

The effectiveness of transcutaneous electrical nerve stimulation in the management of patients with complex regional pain syndrome: A randomized, double-blinded, placebo-controlled prospective study.

To investigate the effect of transcutaneous electrical nerve stimulation (TENS) on clinical recovery in the management of patients with complex regional pain syndrome Type I (CRPS Type I). The study included 30 patients with stage 1 and 2 CRPS Type I in the upper extremities. The patients were randomly assigned into 2 groups, group 1 (n= 15) received conventional TENS therapy for 20 minutes, and group 2 (n= 15) received sham TENS therapy. The standard physical therapy program, which included contrast bath for 20 minutes; whirlpool bath for 15 minutes; assisted active and passive range of motion, and static stretching exercises up to the pain threshold, was also conducted in both groups. Therapy was scheduled for 15 sessions. A visual analogue scale (VAS) was used to assess spontaneous pain. The Leeds Assessment of Neuropathic Signs and Symptoms (LANSS) scale and the Douleur Neuropathique en 4 Questions (DN-4) were used to assess neuropathic pain. In addition, range of motion (ROM) was measured using a goniometer and volumetric measurements were taken to assess edema. Functional capacity was assessed using a hand dynamometer and the Duruöz Hand Index (DHI). All measurements were performed at baseline and after therapy. Significant improvements were achieved in spontaneous and neuropathic pain scores, edema, ROM, and functional capacity in both groups (p< 0.05). However, improvement was found to be significantly greater in group 1 regarding pain intensity, neuropathic pain assessed using LANNS, edema, and in the 2nd-3rd finger ROM measurements (p< 0.05). No significant difference was detected between groups regarding improvements in 4th-5th finger and wrist ROM measurements, grip strength, and DN4 and DHI scores (p> 0.05). The addition of TENS to the physical therapy program was seen to make a significant contribution to clinical recovery in CRPS Type 1.

The use of conventional transcutaneous electrical nerve stimulation in chronic facial myalgia patients.

The aim of this study was to evaluate the efficacy of conventional TENS in women affected by chronic facial myalgia. The study was performed on 49 women affected by chronic facial myalgia randomly allocated in the TENS group (34 women) and the control group (15 women). The subjective level of pain was assessed by the Visual Analogue Scale indicating the mean (VAS MEAN), the maximum (VAS MAX) and the current intensity of pain (VAS NOW). The level of pain at the muscular palpation sites was assessed by the Pericranial Muscle Tenderness Score (PTS) and the Cervical Muscle Tenderness Score (CTS). The TENS therapy lasted for 10weeks, and data were collected at baseline, after 5, 10, 15 and 25weeks. The differences between groups before and after treatment were compared with the Mann-Whitney and the Kolmogorov-Smirnov tests. The intra-group differences were compared with the one-way ANOVA test. The results showed that the VAS MEAN, VAS MAX, PTS and CTS were significantly reduced in the TENS group compared to the control group after 10weeks of TENS (p<0.05). The intra-group analysis revealed a decreasing tendency of VAS MEAN, VAS MAX, VAS NOW, PTS and CTS in the TENS group in a 25-week period (p<0.05). The study demonstrated the efficacy of conventional TENS in patients with chronic facial myalgia and the decrease in both subjective and objective pain. Conventional TENS is a safe, non-invasive, easy-to-administer therapy for chronic facial myalgia.

Transcutaneous electrical nerve stimulation (TENS) for chronic neck pain

Background Chronic neck pain is a highly prevalent condition, affecting 10% to 24% of the general population. Transcutaneous electrical nerve stimulation (TENS) is the noninvasive, transcutaneous use of electrical stimulation to produce analgesia. It is a simple, low-cost and safe intervention used in clinical practice as an adjunct treatment for painful musculoskeletal conditions that have a considerable impact on daily activities, such as chronic neck pain. This review is a split from a Cochrane Review on electrotherapy for neck pain, published in 2013, and focuses specifically on TENS for chronic neck pain. Objectives To evaluate the effectiveness of transcutaneous electrical nerve stimulation (TENS) (alone or in association with other interventions) compared with sham and other clinical interventions for the treatment of chronic neck pain. Search methods We searched Cochrane Back and Neck Trials Register, CENTRAL, MEDLINE, Embase, five other databases and two trials registers to 9 November 2018. We also screened the reference lists of relevant studies to identify additional trials. There were no language, source, or publication date restrictions. Selection criteria We included randomised controlled trials (RCTs) involving adults (≥ 18 years of age) with chronic neck pain (lasting > 12 weeks) that compared TENS alone or in combination with other treatments versus active or inactive treatments. The primary outcomes were pain, disability and adverse events. Data collection and analysis Two independent review authors selected the trials, extracted data and assessed the risk of bias of included studies. A third review author was consulted in case of disagreements. We used the Cochrane 'Risk of bias' tool (adapted by Cochrane Back and Neck), to assess the risk of bias of individual trials and GRADE to assess the certainty of evidence. We used risk ratios (RRs) to measure treatment effects for dichotomous outcomes, and mean differences (MDs) for continuous outcomes, with their respective 95% confidence intervals (CIs). Main results We included seven RCTs with a total of 651 participants, mean age 31.7 to 55.5 years, conducted in three different countries (Turkey, Jordan and China). The length of follow-up ranged from one week to six months. Most RCTs used continuous TENS, with a frequency of 60 Hz to 100 Hz, pulse width of 40 μs to 250 μs and tolerable intensity, described as a tingling sensation without contraction, in daily sessions lasting 20 to 60 minutes. Due to heterogeneity in interventions and outcomes, we did not pool individual study data into meta-analyses. Overall, we judged most studies as being at low risk for selection bias and high risk for performance and detection bias. Based on the GRADE approach, there was very low-certainty evidence from two trials about the effects of conventional TENS when compared to sham TENS at short-term (up to 3 months after treatment) follow-up, on pain (assessed by the Visual Analogue Scale (VAS)) (MD -0.10, 95% CI -0.97 to 0.77) and the percentage of participants presenting improvement of pain (RR 1.57, 95% CI 0.84 to 2.92). None of the included studies reported on disability or adverse events. Authors' conclusions This review found very low-certainty evidence of a difference between TENS compared to sham TENS on reducing neck pain; therefore, we are unsure about the effect estimate. At present, there is insufficient evidence regarding the use of TENS in patients with chronic neck pain. Additional well-designed, -conducted and -reported RCTs are needed to reach robust conclusions.

Evidence‐based Status of Pulsed Radiofrequency Treatment for Patients with Shoulder Pain: A Systematic Review of Randomized Controlled Trials

Review the current evidence-based status of pulsed radiofrequency (PRF) treatment for patients with shoulder pain based on randomized controlled trials (RCTs) to provide a comprehensive analysis and a balanced view of the strengths and weaknesses of this treatment. PubMed, EMBASE, the Cochrane Library, and ISI Web of Science were searched up to July 2014, using the Boolean operators as follows: shoulder pain OR painful shoulder AND pulsed radiofrequency). All prospective randomized controlled trials of PRF treatment for patients with shoulder pain were retrieved. No limitation of the language or publication year existed in our analysis. Five of 114 studies that involved PRF treatment met the inclusion criteria of this review article. These studies compared the clinical outcomes of PRF with those of other treatments such as intra-articular corticosteroid injection and conventional transcutaneous electrical nerve stimulation. All the studies reported improvements in passive range of motion (PROM), visual analog scale (VAS), and Shoulder Pain and Disability Index (SPADI) in PRF treatment that persisted for at least 12weeks. In addition, no complications were reported in all trials. The use of PRF treatment for patients with shoulder pain was observed to result in good clinical efficacy for at least 12weeks with no complication reported. However, it is still unclear from the currently available publications whether PRF is superior to other treatment techniques such as intra-articular corticosteroid and conventional transcutaneous electrical nerve stimulation.

Effectiveness of High-Frequency Electrical Stimulation Following Sensitization With Capsaicin

Although nonnoxious, high-frequency electrical stimulation applied segmentally (ie, conventional transcutaneous electrical nerve stimulation [TENS]) has been proposed to modulate pain, the mechanisms underlying analgesia remain poorly understood. To further elucidate how TENS modulates pain, we examined evoked responses to noxious thermal stimuli after the induction of sensitization using capsaicin in healthy volunteers. We hypothesized that sensitization caused by capsaicin application would unmask TENS analgesia, which could not be detected in the absence of sensitization. Forty-nine healthy subjects took part in a series of experiments. The experiments comprised the application of topical capsaicin (.075%) on the left hand in the C6 dermatome, varying the location of TENS (segmental, left C6 dermatome, vs extrasegmental, right shoulder), and assessing rating of perception (numeric rating scale: 0–10) and evoked potentials to noxious contact heat stimuli. The extrasegmental site was included as a control condition because previous studies indicate no analgesic effect to remote conventional TENS. Conventional TENS had no significant effect on rating or sensory evoked potentials in subjects untreated with capsaicin. However, segmental TENS applied in conjunction with capsaicin significantly reduced sensation to noxious thermal stimuli following a 60-minute period of sensitization. PerspectiveThe study indicates that sensitization with capsaicin unmasks the analgesic effect of conventional TENS on perception of noxious contact heat stimuli. Our findings indicate that TENS may be interacting segmentally to modulate distinct aspects of sensitization, which in turn results in analgesia to thermal stimulation.

Effect of burst TENS and conventional TENS combined with cryotherapy on pressure pain threshold: randomised, controlled, clinical trial

ObjectiveTo assess the immediate effect of conventional and burst transcutaneous electrical nerve stimulation (TENS) in combination with cryotherapy on pain threshold and tolerance in healthy individuals. DesignRandomised, controlled trial. SettingUniversity laboratory. ParticipantsOne hundred and twelve healthy women. InterventionsVolunteers were allocated at random to seven groups (n=16): (1) control, (2) placebo TENS, (3) conventional TENS, (4) burst TENS, (5) cryotherapy, (6) cryotherapy in combination with burst TENS, and (7) cryotherapy in combination with conventional TENS. Pain threshold and tolerance were measured by applying a pressure algometer at the lateral epicondyle of the humerus, before and after each intervention. Main outcome measuresThe primary outcome measure was pressure pain threshold. ResultsA significant increase in pain threshold and tolerance at the 5% level of significance was recorded as follows: burst TENS {pain threshold: mean difference 1.3 [95% confidence interval (CI) 1.4 to 1.2]; pain tolerance: mean difference 3.8 (95% CI 3.9 to 3.7)}, cryotherapy [pain threshold: mean difference 1.3 (95% CI 1.4 to 1.2); pain tolerance: mean difference 1.9 (95% CI 1.8 to 2.0)] and cryotherapy in combination with burst TENS [pain threshold: mean difference 2.6 (95% CI 2.4 to 2.8); pain tolerance: mean difference 4.9 (95% CI 5.0 to 4.8)]. Cryotherapy in combination with burst TENS provided greater analgesia compared with the other groups (P<0.001). ConclusionThese results support the use of cryotherapy in combination with burst TENS to reduce induced pain, and suggest a potentiating effect when these techniques are combined. No such association was found between cryotherapy and conventional TENS.