Effects of burst-type transcutaneous electrical nerve stimulation on cervical range of motion and latent myofascial trigger point pain sensitivity

Efficacy of Myofascial Release With Transcutaneous Electrical Nerve Stimulation Conductive Glove for Neck Myofascial Syndrome: A Randomized Clinical Trial Study

OBJECTIVE

The purpose of this study was to assess the efficacy of a myofascial release (MR) protocol applied with a transcutaneous electrical nerve stimulation (TENS) conductive glove.

METHODS

Eighty individuals with neck myofascial syndrome were randomly divided into 4 groups: (1) MR protocol with a TENS conductive glove (MR+TENS), (2) MR protocol without TENS (MR), (3) conventional TENS protocol (TENS), and (4) placebo TENS (control). All participants attended 6 sessions over a period of 3 weeks. The following measures were evaluated at baseline, at the third week, and at the 1-month follow-up: Pain with the visual analog scale (VAS pain), upper trapezius pressure pain threshold (PPT) with pressure algometry, cervical range of motion (ROM) with goniometry, and disability with the neck disability index (NDI). A 2-way ANOVA with repeated measurements was applied.

RESULTS

Significant changes between the 3 intervention groups and the control group were noted in the VAS and the NDI scores (P < .05) with the MR+TENS group exhibiting the biggest difference. Additionally, MR significantly increased PPT compared to TENS, and even further when applied with the conductive glove (P < .05). Regarding lateral flexion ROM, MR was equally effective either alone or in combination with the glove compared to TENS (P < .05). In contrast, TENS did not appear to affect neck PPT and ROM (P > .05). Finally, no difference between the groups was detected in cervical rotation ROM (P > .05).

CONCLUSION

The MR protocol appears to be more effective in dealing with pain, disability, and lateral flexion ROM than conventional TENS. A TENS conductive glove significantly improves the effects of MR, possibly due to the combined mechanical and electrical stimulation of the muscle.

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

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

Acupuncture-like versus conventional transcutaneous electrical nerve stimulation in the management of active myofascial trigger points: A randomized controlled trial

PURPOSE

Myofascial pain syndrome (MPS) is one of the most common causes of chronic musculoskeletal pain. The transcutaneous electrical nerve stimulation (TENS) is a non-expensive, safe, feasible modality, used recently for the treatment of MPS with promising but limited results. The purpose of this study was to determine the efficacy of acupuncture-like TENS (AL-TENS) vs conventional TENS (C-TENS) in the treatment of active myofascial trigger points.

METHODS

This randomized controlled trial study was carried out with 60 consecutive patients with active trapezius trigger points referred to Physical Medicine and Rehabilitation Clinic. Participants randomly assigned to receive AL-TENS, C-TENS or sham TENS (S-TENS). The Visual Analogue Scale (VAS), Pressure Pain Thresholds (PPTs), and neck range of motion (ROM) were measured at baseline, after the first treatment sessions, after the final treatment session, and 3 months after the end of the last treatment session. Patients function was evaluated by Disabilities of the Arm, Shoulder, and Hand (DASH) at baseline, after the final treatment sessions, and 3 months after the end of intervention.

RESULTS

The interaction effect of time and group was significantly different when evaluating VAS (df = 4.65, F = 2.50, p = 0.038) and DASH (df = 2.63, F = 7.25, p < 0.001) in favor of active groups, as well as neck total lateral bending in favor of AL-TENS group compared other two groups (df = 4.16, F = 5.23, p = 0.001). Both VAS and DASH improved significantly at all follow-ups in AL-TENS and C-TENS groups. Of note, significant immediate improvement in all outcomes was observed only with AL-TENS.

CONCLUSIONS

According to the present study, both AL-TENS and C-TENS were superior to placebo in pain reduction and functional improvement. Although both TENS techniques have similar efficiency on pain reduction, functional and pain perception improvement, the AL-TENS was the superior approach when evaluating neck lateral bending ROM.

Transcutaneous electrical stimulation in neck pain: A systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

The objective of this systematic review was to investigate the effectiveness of electrical stimulation (ES) for neck pain (NP).

DATABASES AND DATA TREATMENT

The databases CINAHL, Embase, MEDLINE (via OVID), PEDro and Web of Science were searched, with no date restrictions. Two independent reviewers selected randomized controlled trials (RCTs) reporting pain, range of motion or psychosocial factors in people with NP, in which ES was applied. Methodological quality was assessed using the PEDro scale. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) was used to evaluate the quality of evidence. Thirty studies met eligibility criteria.

RESULTS

Main results showed evidence of moderate quality that ES combined with other intervention significantly decreases the pain intensity compared to other intervention immediately post-treatment and at short-term follow-up; evidence of low quality showed significant effects of ES combined with other intervention in decreasing neck disability compared to other intervention immediately post-treatment; evidence of very-low quality that ES increased the pressure pain threshold compared to placebo immediately post-treatment and that ES + other intervention also increased the pressure pain threshold compared to other intervention at short-term follow-up.

CONCLUSIONS

ES combined with other intervention seems to be useful to relieve pain and to improve disability in people with NP, however, more studies are needed.

SIGNIFICANCE

Electrical stimulation seems to be effective for improving pain intensity, immediately post-treatment in people with neck pain, mainly as an adjunct therapeutic modality. Nevertheless, high-quality RCTs are still needed to investigate the efficacy of electrical stimulation in neck pain.

Complementary and Alternative Modalities (CAM) for pain management in musculoskeletal diseases (MSDs)

Musculoskeletal diseases are a group of clinical conditions affecting the body's movement and remain a common source of pain affecting the quality of life. The aetio-pathological reasons for pain associated with musculoskeletal diseases can be varied and complex. Conventional medicine can treat or modify pain due to musculoskeletal diseases; however, these may be associated with some side effects and at times may not be able to relieve pain completely. These treatment modalities also have ceiling effects like doses of analgesics, the number of nerve blocks, etc. Complementary and Alternative Medicine (CAM) provides a supplementary, unconventional modality to alleviate discomfort and disability associated with these mostly chronic conditions to manage activities of daily living. These modalities have been variedly combined with conventional management for symptom control and thus improve day-to-day activities. We assess the role of commonly used CAM modalities in the management of pain arising from Musculoskeletal diseases.

Ischemic Pressure vs Postisometric Relaxation for Treatment of Rhomboid Latent Myofascial Trigger Points: A Randomized, Blinded Clinical Trial

OBJECTIVE

The purpose of this study was to investigate the effects of ischemic pressure (IP) vs postisometric relaxation (PIR) on rhomboid-muscle latent trigger points (LTrPs).

METHODS

Forty-five participants with rhomboid-muscle LTrPs were randomly assigned into 3 groups and received 3 weeks of treatment-group A: IP and traditional treatment (infrared radiation, ultrasonic therapy, and transcutaneous electrical nerve stimulation); group B: PIR and traditional treatment; and group C: traditional treatment. Shoulder pain and disability, neck pain and disability, and pressure pain threshold (PPT) of 3 points on each side were measured before and after treatment.

RESULTS

Multivariate analysis of variance indicated a statistically significant Group × Time interaction (P = .005). The PPT for the right lower point was increased in group A more than in groups B or C. Neck pain was reduced in group B more than in group C. Moreover, shoulder and neck disability were reduced in both groups A and B more than in group C. The PPTs of the left lower and middle points were increased in group B compared with groups A and C. The PPT of the left upper point was increased in group A more than in group C. There were significant changes in all outcomes in the 2 experimental groups (P < .05). No changes were found in the control group except in pain intensity, shoulder disability, and PPT of the left lower point.

CONCLUSION

This study found that IP may be more effective than PIR regarding PPT, but both techniques showed changes in the treatment of rhomboid-muscle LTrPs.

Criteria Used for the Diagnosis of Myofascial Trigger Points in Clinical Trials on Physical Therapy: Updated Systematic Review

OBJECTIVE

The objective of this study was to conduct an updated systematic review of diagnostic criteria for myofascial trigger points (MTrPs) used in clinical trials of physical therapy interventions from 2007 to 2019.

METHODS

MEDLINE and Physiotherapy Evidence Database (PEDro) were searched using the following MeSH keywords: "trigger points," "trigger point," "myofascial trigger point," "myofascial trigger points," "myofascial pain," and "myofascial pain syndrome." The MeSH keywords were combined by using Boolean operators "OR"/"AND." All physiotherapy clinical trials including patients with musculoskeletal conditions characterized by at least 1 active MTrP or latent MTrP in any body area were selected. We pooled data from an individual criterion and criteria combinations used to diagnose MTrPs. The protocol was developed in accordance with the PRISMA-P guidelines.

RESULTS

Of 478 possibly relevant publications, 198 met the inclusion criteria. Of these 198 studies, 129 studies (65.1%) stated specifically the diagnostic criteria used for MTrPs in the main text, 56 studies (28.3%) failed to report any method whereby MTrP was diagnosed, and 13 studies (6.6%) adopted expert-based definitions for MTrPs without specification. Of 129 studies, the 6 criteria applied most commonly were: "spot tenderness" (n=125, 96.9%), "referred pain" (95, 73.6%), "local twitch response" (63, 48.8%), pain recognition (59, 45.7%), limited range of motion" (29, 22.5%), and "jump sign" (10, 7.8%). Twenty-three combinations of diagnostic criteria were identified. The most frequently used combination was "spot tenderness," "referred pain," and "local twitch response" (n=28 studies, 22%).

CONCLUSIONS

A number of the included studies failed in properly reporting the MTrP diagnostic criteria. Moreover, high variability in the use of MTrP diagnostic was also observed. Spot tenderness, referred pain, and local twitch response were the 3 most popular criteria (and the most frequently used combination). A lack of transparency in the reporting of MTrP diagnostic criteria is present in the literature.

REGISTRY

This systematic review was registered under the Centre for Reviews and Dissemination, PROSPERO number: CRD42018087420.

Myofascial pain syndrome and trigger points: evaluation and treatment in patients with musculoskeletal pain

PURPOSE OF REVIEW

Myofascial pain syndrome is a chronic pain condition characterized by the presence of myofascial trigger point, a hyperirritable painful spot involving a limited number of muscle fibers. The literature suggest that myofascial trigger points should be considered peripheral pain generators and this critical review will summarize recent findings concerning the clinical evaluation and the treatment of myofascial trigger points.

RECENT FINDINGS

The clinical features of myofascial trigger points and their contribution to the patient pain and disability have been detailed in several recent studies, which support the clinical relevance of the condition. Recent studies reported that manual palpation to identify MTrPs has good reliability, although some limitations are intrinsic to the diagnostic criteria. During the last decade, a plethora of treatments have been proposed and positive effects on pain and function demonstrated.

SUMMARY

The myofascial trigger point phenomenon has good face validity and is clinically relevant. Clinicians are encouraged to consider the contribution of myofascial trigger points to the patient's pain and disability through a careful medical history and a specific manual examination. Patients with myofascial trigger points will benefit from a multimodal treatment plan including dry needling and manual therapy techniques. Internal and external validity of research within the field must be improved.

Benefits of dry needling of myofascial trigger points on autonomic function and photoelectric plethysmography in patients with fibromyalgia syndrome

Background:

Fibromyalgia syndrome (FMS) is a condition characterised by the presence of chronic, widespread musculoskeletal pain, low pain threshold and hyperalgesia. Myofascial trigger points (MTrPs) may worsen symptoms in patients with FMS.

Objective:

The purpose of this randomised controlled trial was to compare the effects of dry needling and transcutaneous electrical nerve stimulation (TENS) on pain intensity, heart rate variability, galvanic response and oxygen saturation (SpO2).

Methods:

74 subjects with FMS were recruited and randomly assigned to either the dry needling group or the TENS group. Outcomes measures (pain intensity, heart rate variability, galvanic skin response, SpO2 and photoplethysmography) were evaluated at baseline and after 6 weeks of treatment. 2×2 mixed-model analyses of variance (ANOVAs) were performed.

Results:

The mixed-model ANOVAs showed significant differences between groups for the sensory dimension of pain, affective dimension of pain, total dimension of pain, visual analogue scale (VAS) and present pain intensity (PPI) (P=0.001). ANOVAs also showed that significant differences between groups were achieved for very low frequency power of heart rate variability (P=0.008) and low frequency power (P=0.033). There were no significant differences in dry needling versus TENS groups on the spectral analysis of the photoplethysmography and SpO2.

Conclusions:

This trial showed that application of dry needling therapy and TENS reduced pain attributable to MTrPs in patients with FMS, with greater improvements reported in the dry needling group across all dimensions of pain. Additionally, there were between-intervention differences for several parameters of heart rate variability and galvanic skin responses.

Trial registration number:

NCT02393352

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.

The Effect of Electric Stimulation Techniques on Pain and Tenderness at the Myofascial Trigger Point: A Systematic Review

BACKGROUND

Myofascial pain is a prevalent chronic pain disorder, affecting a large proportion of the general population. Electric stimulation techniques such as transcutaneous electric stimulation (TENS) and electroacupuncture have been shown to be effective for managing chronic pain conditions including myofascial pain. The goal of this study was to review the literature on the effectiveness of electric stimulation techniques on myofascial pain.

METHODS

A comprehensive systematic search of three databases-Medline, EMBASE, and Cochrane CENTRAL-was conducted using key words related to myofascial pain and trigger points, as well as various electric stimulation techniques. A total of 15 articles passed the inclusion and exclusion criteria for the study. Data were extracted from these studies and assessed qualitatively and quantitatively. Standardized mean differences (SMDs) were computed from pain intensity measures extracted from these studies. Subgroup analyses were performed to assess the effectiveness of treatment modality, number of treatment sessions, frequency of stimulation, location of treatment, and duration of treatment.

RESULTS

The SMD for electric stimulation techniques on reported pain intensity was significant (P = 0.03), as was the SMD for the electroacupuncture subgroup (P = 0.02); the TENS subgroups' effect was not significant (P = 0.17). The subgroup analyses tentatively suggest that frequency and number of treatments do not influence pain intensity, whereas the duration of treatment may have an effect. The qualitative results of this study revealed variability in the results among studies delivering TENS treatments.

CONCLUSIONS

Electric stimulation is effective at mitigating reported pain intensity at the location of the trigger point. Electroacupuncture presented with significant and larger effect sizes of improvement relative to TENS for reported pain intensity. Given that this review included a small number of studies, there is a need for additional research to confirm its findings. Additionally, studies assessing the parameters and physiological location of treatment are needed to inform the clinical use and recommendations of electric stimulation treatments.

Segmental and extrasegmental hypoalgesic effects of low-frequency pulsed current and modulated kilohertz-frequency currents in healthy subjects: randomized clinical trial

Objective: To compare the segmental and extrasegmental hypoalgesic effects of TENS, IFC and Aussie current on pressure pain threshold (PPT) during and after stimulation in healthy subjects. The second objective was to compare the sensory comfort related to electrical stimulation.Material and Methods: 120 healthy subjects were randomized in TENS, IFC, Aussie current or placebo groups. The electrical stimulation was administered on the forearm. The PPT was measured on the forearm (segmental measure) and on the lower leg (extrasegmental measure) by an algometer at baseline, during and after stimulation of the forearm, and the sensory comfort in relation to electrical stimulation was measured with a visual analogue scale. Statistical analysis was performed using linear mixed models for PPT analysis and one-way ANOVA for sensory comfort analysis.Results: The TENS, IFC and Aussie current increased the segmental and extrasegmental PPTs during application of current compared to the placebo. The PPTs measures and sensory comfort were not significantly different between the TENS, IFC and Aussie current groups.Conclusions: Segmental and extrasegmental hypoalgesic effects may be produced using TENS, IFC or Aussie currents in healthy subjects. Furthermore, all of them presented a similar sensory comfort.

Effect of adding interferential current stimulation to exercise on outcomes in primary care patients with chronic neck pain: a randomized controlled trial

OBJECTIVE

To evaluate the effect of adding interferential current stimulation to exercise on pain, disability, psychological status and range of motion in patients with neck pain.

DESIGN

A single-blinded randomized controlled trial.

SETTING

Primary care physiotherapy units.

SUBJECTS

A total of 84 patients diagnosed with non-specific mechanical neck pain. This sample was divided into two groups randomly: experimental (n = 42) versus control group (n = 42).

INTERVENTIONS

Patients in both groups had a supervised therapeutic exercise programme, with the experimental group having additional interferential current stimulation treatment.

MAIN MEASURES

The main measures used were intensity of neck pain according to the Visual Analogue Scale; the degree of disability according to the Neck Disability Index and the CORE Outcome Measure; anxiety and depression levels according to the Goldberg scale; apprehension as measured by the Personal Psychological Apprehension scale; and the range of motion of the cervical spine. The sample was evaluated at baseline and posttreatment (10 sessions/two weeks).

RESULTS

Statistically significant differences between groups at posttreatment were observed for Visual Analogue Scale (2.73 ± 1.24 vs 4.99 ± 1.56), Neck Disability Index scores (10.60 ± 4.77 vs 18.45 ± 9.04), CORE Outcome Measure scores (19.18 ± 9.99 vs 35.12 ± 13.36), Goldberg total score (6.17 ± 4.27 vs 7.90 ± 4.87), Goldberg Anxiety subscale, Personal Psychological Apprehension Scale scores (28.17 ± 9.61 vs 26.29 ± 11.14) and active and passive right rotation.

CONCLUSIONS

Adding interferential current stimulation to exercise resulted in better immediate outcome across a range of measures.

Reliability of measurements for sub-painful and painful perception on artificial electrical stimulations

Artificial electrical stimulation is a common type of stimulus to induce sub-painful and painful sensation in clinical or neuroscience experiments. The Numerical Rating Scale (NRS) is often used to evaluate subjective perception due to external stimulations. Yet the relationship between the intensity levels of electrical stimulations and self-perception has seldom been examined. The aim of the study was to obtain evidence on the reliability and accuracy of sub-painful and painful perceptions of healthy participants using the NRS under different levels of electrical stimulus. A total of 72 pain-free healthy volunteers (female=44) were recruited. In the first experiment, each participant was given different levels of a non-nociceptive or nociceptive electrical stimulus and then asked to give a perception rating based on an 11-point NRS. In the second experiment, each participant was asked to memorize 5 levels of sub-nociceptive or nociceptive stimuli and to recognize the level of stimulus given each time. For the NRS rating task, intraclass coefficients (ICCs) reached satisfactory level for sub-nociceptive (0.85<ICC<0.93) and nociceptive stimulation (0.90<ICC<0.96). The ICCs were the highest for the weakest sub-nociceptive and nociceptive stimuli. For the stimulus recognition task, accuracy was also found to be highest for the weakest sub-nociceptive stimulus (κ=0.67) and lowest for the strongest nociceptive stimulus (κ=0.34). The results suggest that, with adequate training, NRS can be a reliable measurement tool for both sub-painful and painful rating due to electrical stimulation.

Short-term transcutaneous electrical nerve stimulation reduces pain and improves the masticatory muscle activity in temporomandibular disorder patients: a randomized controlled trial

Studies to assess the effects of therapies on pain and masticatory muscle function are scarce.

Transcutaneous Electrical Nerve Stimulation in Patients With Knee Osteoarthritis: Evidence From Randomized-controlled Trials

OBJECTIVES

Transcutaneous electrical nerve stimulation (TENS) has been reported to relieve pain and improve function in patients with knee osteoarthritis. The purpose of this systematic review and meta-analysis was to evaluate the efficacy of TENS for the management of knee osteoarthritis.

METHODS

We searched Embase, PubMed, CENTRAL, SIGLE, PEDro, and clinicaltrials.gov, up to June 2014 for literature related to TENS used for the treatment of knee osteoarthritis. Two authors independently screened the searched records based on the title and abstract. Information including the authors, study design, mean age, sex, study population, stimulation frequency (of TENS), outcome measures, and follow-up periods were extracted by the 2 authors.

RESULTS

Eighteen trials were included in the qualitative systematic review, and 14 were included in the meta-analysis. TENS significantly decreased pain (standard mean difference, -0.79; 95% confidence interval [CI], -1.31 to -0.27; P<0.00001) compared with control groups. There was no significant difference in the Western Ontario and McMaster Universities Osteoarthritis Index (standard mean differences, -0.13; 95% CI, -0.35 to 0.1; P=0.09) or the rate of all-cause discontinuation (risk ratio, 0.77; 95% CI, 0.48 to 1.22; P=0.94) between the TENS and control groups.

DISCUSSION

TENS might relieve pain due to knee osteoarthritis. Further randomized-controlled trials should focus on large-scale studies and a longer duration of follow-up.

Immediate and short-term effects of the combination of dry needling and percutaneous TENS on post-needling soreness in patients with chronic myofascial neck pain

Background

Dry needling (DN) and percutaneous electrical nerve stimulation (PENS) are widely used techniques in the treatment of myofascial pain.

Objective

To investigate the immediate and short-term effects of the combination of DN and PENS compared to DN alone on the upper trapezius muscle.

Method

This is a 72-hour follow-up single-blinded randomized controlled trial. Sixty-two volunteer patients with chronic myofascial neck pain with active Myofascial Trigger Points (MTrPs) in the upper trapezius muscle were recruited. Randomization was performed, and 31 patients received DN treatment (DN group) and 31 received DN and PENS (DN+PENS group). The primary outcomes were neck disability index (NDI) and visual analog scale for pain for both post-needling soreness (PNS) and neck pain intensity (NPI). Pressure pain threshold (PPT) and cervical range of motion (CROM) were the secondary outcomes.

Results

We detected between-group differences in NPI and PNS in favor of the DN+PENS group immediately after treatment. No between-group differences in NDI were observed.

Conclusion

PENS application after dry needling treatment is more effective than dry needling alone for decreasing soreness in the short term and improving neck pain intensity immediately in patients with myofascial chronic neck pain.

Novel Noxipoint Therapy versus Conventional Physical Therapy for Chronic Neck and Shoulder Pain: Multicentre Randomised Controlled Trials

As chronic pain affects 115 million people and costs $600B annually in the US alone, effective noninvasive nonpharmacological remedies are desirable. The purpose of this study was to determine the efficacy and the generalisability of Noxipoint therapy (NT), a novel electrotherapy characterised by site-specific stimulation, intensity-and-submodality-specific settings and a immobilization period, for chronic neck and shoulder pain. Ninety-seven heavily pretreated severe chronic neck/shoulder pain patients were recruited; 34 and 44 patients were randomly allocated to different treatment arms in two patient-and-assessor-blinded, randomised controlled studies. The participants received NT or conventional physical therapy including transcutaneous electrical nerve stimulation (PT-TENS) for three to six 90-minute sessions. In Study One, NT improved chronic pain (−89.6%, Brief Pain Inventory, p < 0.0001, 95% confidence interval), function (+77.4%, range of motion) and quality of life (+88.1%) at follow-up (from 4 weeks to 5 months), whereas PT-TENS resulted in no significant changes in these parameters. Study Two demonstrated similar advantages of NT over PT-TENS and the generalisability of NT. NT-like treatments in a randomised rat study showed a similar reduction in chronic hypersensitivity (−81%, p < 0.01) compared with sham treatments. NT substantially reduces chronic neck and shoulder pain, restores function, and improves quality of life in a sustained manner.

Short-Term Effects of Kinesio Taping and Cross Taping Application in the Treatment of Latent Upper Trapezius Trigger Points: A Prospective, Single-Blind, Randomized, Sham-Controlled Trial

Kinesio taping (KT) may be a new treatment in patients with myofascial trigger points (MTrPs). A new method available for taping practitioners is cross taping (CT). The main objective was to determine how CT, KT, and medical adhesive tape (sham group) affect the subjective assessment of resting bioelectrical activity and pain of the upper trapezius muscle (UT) in patients with MTrPs. 105 volunteers were recruited to participate. The primary outcome was resting bioelectrical activity of UT muscle as assessed by surface electromyography (sEMG) in each group and pain intensity on a visual analog scale (VAS). Assessments were collected before and after intervention and after the 24-hours follow-up. No significant differences were observed in bioelectrical activity of UT between pre-, post-, and follow-up results. In three groups patients had significantly lower pain VAS score after the intervention (CT—p < 0.001, KT—p < 0.001, and sham—p < 0.01). The Kruskal-Wallis ANOVA showed no significant differences in almost all measurements between groups. The application of all three types of tapes does not influence the resting bioelectrical activity of UT muscle and may not lead to a reduction in muscle tone in the case of MTrPs.

Pain reduction in myofascial pain syndrome by anodal transcranial direct current stimulation combined with standard treatment: a randomized controlled study

BACKGROUND

Myofascial pain syndrome (MPS) in the shoulder is among the most prevalent pain problems in the middle-aged population worldwide. Evidence suggests that peripheral and central sensitization may play an important role in the development and maintenance of shoulder MPS. Given previous research supporting the potential efficacy of anodal transcranial direct current stimulation (tDCS) for modulating pain-related brain activity in individuals with refractory central pain, we hypothesized that anodal tDCS when applied over the primary motor cortex (M1) combined with standard treatment will be more effective for reducing pain in patients with MPS than standard treatment alone.

METHODS AND MATERIALS

Study participants were randomized to receive either (1) standard treatment with 5 consecutive days of 1 mA anodal tDCS over M1 for 20 minutes; or (2) standard treatment plus sham tDCS. Measures of pain intensity, shoulder passive range of motion (PROM), analgesic medication use, and self-reported physical functioning were administered before treatment and again at posttreatment and 1-, 2-, 3-, and 4-week follow-up.

RESULTS

Thirty-one patients with MPS were enrolled. Participants assigned to the active tDCS condition reported significantly more pretreatment to posttreatment reductions in pain intensity that were maintained at 1-week posttreatment, and significant improvement in shoulder adduction PROM at 1-week follow-up than participants assigned to the sham tDCS condition.

CONCLUSIONS

Five consecutive days of anodal tDCS over M1 combined with standard treatment appears to reduce pain intensity and may improve PROM, faster than standard treatment alone. Further tests on the efficacy and duration of effects of tDCS in the treatment of MPS are warranted.

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.

Ischemic Compression After Dry Needling of a Latent Myofascial Trigger Point Reduces Postneedling Soreness Intensity and Duration

OBJECTIVE

To investigate the effect of ischemic compression (IC) versus placebo and control on reducing postneedling soreness of 1 latent myofascial trigger point and on improving cervical range of motion (CROM) in asymptomatic subjects.

DESIGN

A randomized, double-blind, placebo-controlled trial with 72-hour follow-up.

SETTING

A university community.

PARTICIPANTS

Asymptomatic volunteers (N = 90: 40 men and 50 women) aged 18 to 39 years (mean ± standard deviation [SD]: 22 ± 3 years).

INTERVENTION

All subjects received a dry needling application over the upper trapezius muscle. Participants were then randomly divided into 3 groups: a treatment group who received IC over the needled trapezius muscle, a placebo group who received sham IC, and a control group who did not receive any treatment after needling.

MAIN OUTCOME MEASURES

Visual analog scale (VAS; during needling, at posttreatment and 6, 12, 24, 48, and 72 hours) and CROM (at preneedling, postneedling, and 24 and 72 hours).

RESULTS

Subjects in the IC group showed significantly lower postneedling soreness than the placebo and the control group subjects immediately after treatment (mean ± standard deviation [SD]: IC, 20.1 ± 4.8; placebo, 36.7 ± 4.8; control, 34.8 ± 3.6) and at 48 hours (mean ± SD: IC, 0.6 ± 1; placebo, 4.8 ± 1; control, 3.8 ± 0.7). In addition, subjects in the dry needling+IC group showed significantly lower postneedling soreness duration (P = .026). All subjects significantly improved CROM in contralateral lateroflexion and both homolateral and contralateral rotations, but only the improvements found in the IC group reached the minimal detectable change.

CONCLUSIONS

IC can potentially be added immediately after dry needling of myofascial trigger point in the upper trapezius muscle because it has the effect of reducing postneedling soreness intensity and duration. The combination of dry needling and IC seems to improve CROM in homolateral and contralateral cervical rotation movements.

Pain intensity and cervical range of motion in women with myofascial pain treated with acupuncture and electroacupuncture: a double-blinded, randomized clinical trial

BACKGROUND

Acupuncture stimulates points on the body, influencing the perception of myofascial pain or altering physiologic functions.

OBJECTIVE

The aim was to evaluate the effect of electroacupuncture (EAC) and acupuncture (AC) for myofascial pain of the upper trapezius and cervical range of motion, using SHAM acupuncture as control.

METHOD

Sixty women presenting at least one trigger point at the upper trapezius and local or referred pain for more than six months were randomized into EAC, AC, and SHAM groups. Eight sessions were scheduled and a follow-up was conducted after 28 days. The Visual Analog Scale assessed the intensity of local and general pain. A fleximeter assessed cervical movements. Data were analyzed using paired t or Wilcoxon's tests, ANOVA or Friedman or Kruskal-Wallis tests and Pearson's correlation (α=0.05).

RESULTS

There was reduction in general pain in the EAC and AC groups after eight sessions (P<0.001). A significant decrease in pain intensity occurred for the right trapezius in all groups and for the left trapezius in the EAC and AC groups. Intergroup comparisons showed improvement in general pain in the EAC and AC groups and in local pain intensity in the EAC group (P<0.05), which showed an increase in left rotation (P=0.049). The AC group showed increases in inclination (P=0.005) sustained until follow-up and rotation to the right (P=0.032).

CONCLUSION

EAC and AC were effective in reducing the pain intensity compared with SHAM. EAC was better than AC for local pain relief. These treatments can assist in increasing cervical range of motion, albeit subtly.

Sensory and motor thresholds of transcutaneous electrical stimulation are influenced by gender and age

BACKGROUND

Transcutaneous electrical stimulation (ES) is a therapeutic procedure used in rehabilitation. However, the effectiveness of it depends on sensory responses to pain and motor control in neuromuscular recruitment, considering the differences related to gender and age of the subjects treated, as well as the intensity and frequency of ES.

OBJECTIVE

To determine the threshold of sensory perception (TSP) and the threshold of motor response (TMR) in young and elderly individuals of both genders.

DESIGN

Randomized controlled clinical trial.

SETTING

General community.

PARTICIPANTS

Eighty volunteers with no history of systemic diseases were selected to participate in the study: 40 men and 40 women were subdivided by convenience sampling and age group into young male and female (age 21.6 ± 2.4 years) groups as well as into elderly female and male groups (age 72.6 ± 6.1 years).

INTERVENTIONS

The participants received electrical stimulation (ES) at 5 and 50 Hz, with pulse durations of 20, 100, 400, 1000, and 3000 μs applied on the flexor muscle bellies of the wrist and fingers.

MAIN OUTCOME MEASURES

TSP was identified as the first sensation of increased current intensity and TMR as the minimum muscle contraction detected. The results were submitted to analysis of variance, followed by the Tukey's test, with a significance level of 5%.

RESULTS

TSP was lower than TMR for all pulse durations, regardless of gender and age. In women, TSP was lower than that in young and elderly men at both frequencies. However, TSP was higher in elderly subjects than in younger subjects at 50 Hz for both genders. Age also affected the TMR, presenting higher thresholds in elderly subjects of both genders at 50 Hz; however the same occurred only in male subjects at 5 Hz.

CONCLUSION

Age and gender interfere directly with ES. These variables should be considered during rehabilitation because they indicate that electrical stimulation in elderly women should be carefully performed, as they have lower thresholds than elderly men when polarized currents are used, and there is a risk of skin lesion because of their high thresholds.

Clinical implication of latent myofascial trigger point

Myofascial trigger points (MTrPs) are hyperirritable points located within a taut band of skeletal muscle or fascia, which cause referred pain, local tenderness and autonomic changes when compressed. There are fundamental differences between the effects produced by the two basic types of MTrPs (active and latent). Active trigger points (ATrPs) usually produce referred pain and tenderness. In contrast, latent trigger points (LTrPs) are foci of hyperirritability in a taut band of muscle, which are clinically associated with a local twitch response, tenderness and/or referred pain upon manual examination. LTrPs may be found in many pain-free skeletal muscles and may be "activated" and converted to ATrPs by continuous detrimental stimuli. ATrPs can be inactivated by different treatment strategies; however, they never fully disappear but rather convert to the latent form. Therefore, the diagnosis and treatment of LTrPs is important. This review highlights the clinical implication of LTrPs.