Insights About the Neuroplasticity State on the Effect of Intramuscular Electrical Stimulation in Pain and Disability Associated With Chronic Myofascial Pain Syndrome (MPS): A Double-Blind, Randomized, Sham-Controlled Trial

Percutaneous Electrical Stimulation Improves Chronic Knee Pain and Function: A Systematic Review and Meta-analyses

OBJECTIVES

The aim of this systematic review and meta-analysis was to evaluate the effectiveness of percutaneous electrical stimulation in the modulation of pain and its implication in the function of patients with a painful knee condition.

MATERIALS AND METHODS

A search was conducted from database inception to September 2023 across PubMed, Web of Science, and Scopus databases. Randomized controlled trials were included. Two reviewers performed independent data extraction and methodologic quality assessment of the studies. Study quality was assessed using the physiotherapy evidence database Scale and the risk of bias was evaluated with the Cochrane Assessment tool.

RESULTS

Eight studies were included. A significant statistical effect was found ( P < 0.001) for reducing pain and improving function after treatment. In addition, a significant statistical effects were identified for reducing pain ( P = 0.009) and improving function ( P < 0.001) after follow-up. The risk of bias was low.

CONCLUSION

This review showed a positive effect of applying the percutaneous electrical stimulation for reducing pain and improving function in adults with a painful knee.

Immediate effects of percutaneous electrical nerve stimulation in patients with lateral elbow pain

INTRODUCTION

Ultrasound guided-percutaneous electrical nerve stimulation appears to be effective in the treatment of chronic musculoskeletal pain.

OBJECTIVE

To investigate the immediate effects of one session of percutaneous electrical nerve stimulation on the radial nerve in patients with lateral elbow pain.

METHODS

A randomized clinical trial was conducted. Sixty patients with chronic lateral elbow pain were allocated into real-percutaneous electrical nerve stimulation (n = 30) or sham-percutaneous electrical nerve stimulation (n = 30) where the patients received one-single session of the real or sham percutaneous stimulation on the radial nerve, respectively. Pressure pain thresholds, pain intensity, pain-free grip strength, and the self-perceived improvement were evaluated after the intervention.

RESULTS

Significant differences between groups for pain intensity (-11.55, 95% CI -21.79 to -1.30, p < .028), but not for pressure pain threshold or pain-free grip strength, were found. Patients receiving real-percutaneous stimulation had significant improvement in pain-free grip strength on the treated side. The proportion of individuals reporting moderate to large self-perceived improvement (≥4) was significantly higher (p = .026) after real-percutaneous stimulation than after sham-percutaneous stimulation.

CONCLUSION

A single session of real-percutaneous electrical nerve stimulation targeting the radial nerve in subjects with lateral elbow pain decreased pain intensity between groups and increased pain-free grip strength on the treated side but not between groups.

Short-term effect of frequency specific intramuscular electrical stimulation on post dry needling soreness of upper fibers of trapezius: A randomized controlled trial

OBJECTIVES

The purpose of this study was to compare the effect of frequency specific intramuscular electrical stimulation on post trigger point dry needling soreness.

BACKGROUND

Dry needling (DN) with intramuscular electrical stimulation (DN/IMES) has been shown to be effective in reducing post needling soreness. The effect of frequency specific intramuscular electrical stimulation on post needling soreness has not been studied abundantly, but initial results are favorable. This study investigated the effect of frequency specific intramuscular electrical stimulation on post needling soreness.

METHODS

A convenience sample of 45 (α = 0.05, power = 95%) subjects was recruited for this study and randomly assigned to DN (n = 15), DN/IMES [f-2Hz] (n = 15) and DN/IMES [f-100Hz] (n = 15) groups. Pain Pressure Threshold (PPT) and Numeric Pain Rating Scale (NPRS) were measured before and 24 hours after the intervention.

RESULT

Both DN/IMES [f-2Hz and 100 Hz] groups showed statistically significant improvement in NPRS (p = 0.001 and 0.00005, respectively) and PPT (p = 0.004 and 0.0002, respectively). No statistically significant changes were observed in DN group in NPRS (p = 0.726) and PPT (p = 0.238).

CONCLUSION

Both dry needling with Intramuscular electrical stimulation (DN/IMES [f-2Hz and 100Hz]) groups demonstrated statistically significant improvement in soreness as compared to DN group, but DN/IMES [f-100 Hz] group showed more significant improvement as compared to DN/IMES [f-2 Hz] group in reducing post needling soreness.

Bioelectronics for electrical stimulation: materials, devices and biomedical applications

Bioelectronics is a hot research topic, yet an important tool, as it facilitates the creation of advanced medical devices that interact with biological systems to effectively diagnose, monitor and treat a broad spectrum of health conditions. Electrical stimulation (ES) is a pivotal technique in bioelectronics, offering a precise, non-pharmacological means to modulate and control biological processes across molecular, cellular, tissue, and organ levels. This method holds the potential to restore or enhance physiological functions compromised by diseases or injuries by integrating sophisticated electrical signals, device interfaces, and designs tailored to specific biological mechanisms. This review explains the mechanisms by which ES influences cellular behaviors, introduces the essential stimulation principles, discusses the performance requirements for optimal ES systems, and highlights the representative applications. From this review, we can realize the potential of ES based bioelectronics in therapy, regenerative medicine and rehabilitation engineering technologies, ranging from tissue engineering to neurological technologies, and the modulation of cardiovascular and cognitive functions. This review underscores the versatility of ES in various biomedical contexts and emphasizes the need to adapt to complex biological and clinical landscapes it addresses.

Virtual reality therapy for myofascial pain: Evolving towards an evidence-based non-pharmacologic adjuvant intervention

Myofascial pain syndrome (MPS) is a highly prevalent and burdensome cause of pain globally, representing a major focus of chronic pain management. Management of MPS is highly variable, with therapies ranging from interventional approaches to physical therapy. Virtual reality (VR) is a novel form of therapy being actively explored as an adjuvant to procedural sedation in the acute pain setting, and increasingly as a means of chronic pain management through programs that facilitate pain education, physical therapy and mindfulness, among other approaches. However, to date, there are minimal clinical studies assessing VR therapy within the context of MPS treatments. Given the existing volume of work published in the acute pain setting and the translational work exploring VR and neuroplasticity in chronic pain, we make the case here that it is an appropriate time to consider exploring VR therapy as a non-pharmacological adjuvant treatment for MPS.

Effect of Different Physical Therapy Interventions on Brain-Derived Neurotrophic Factor Levels in Chronic Musculoskeletal Pain Patients: A Systematic Review

OBJECTIVE

The main objectives of this review were, firstly, to study the effect of different physiotherapy interventions on BDNF levels, and, secondly, to analyze the influence of physiotherapy on pain levels to subsequently draw conclusions about its possible relationship with BDNF.

BACKGROUND

Based on the theory that neurotrophic factors such as BDNF play a fundamental role in the initiation and/or maintenance of hyperexcitability of central neurons in pain, it was hypothesized that the levels of this neurotrophic factor may be modified by the application of therapeutic interventions, favoring a reduction in pain intensity.

METHODS

A literature search of multiple electronic databases (Pubmed, PsycINFO, Medline (Ebsco), Scopus, WOS, Embase) was conducted to identify randomized control trials (RCTs) published without language restrictions up to and including March 2022. The search strategy was based on the combination of medical terms (Mesh) and keywords relating to the following concepts: "pain", "chronic pain", "brain derived neurotrophic factor", "BDNF", "physiotherapy", and "physical therapy". A total of seven papers were included.

RESULTS

There were two studies that showed statistically significant differences in pain intensity reduction and an increase in the BDNF levels that used therapies such as rTMS and EIMS in patients with chronic myofascial pain. However, the same conclusions cannot be drawn for the other physical therapies applied.

CONCLUSIONS

rTMS and EIMS interventions achieved greater short-term reductions in pain intensity and increased BDNF over other types of interventions in chronic myofascial pain patients, as demonstrated by a moderate amount of evidence. In contrast, other types of physical therapy (PT) interventions did not appear to be more effective in decreasing pain intensity and increasing BDNF levels than placebo PT or minimal intervention, as a low amount of evidence was found.

Effects of percutaneous neuromodulation in neuromusculoskeletal pathologies: A systematic review

BACKGROUND

Percutaneous neuromodulation (PNM) consists in using electrical stimulation on a peripheral nerve by using a needle as an electrode in order to lessen the pain and restore both neuromuscular and nervous system functions. The aims of the present study were to evaluate the current scientific evidence of the effects of PNM on pain and physical capabilities in neuromusculoskeletal injuries.

METHODS

Data sources: There was used the PRISMA protocol. In order to do the literature research, there were used the PubMed, Cochrane, Scopus, and Web of Science databases. Study selection or eligibility criteria: There were also included experimental clinical trials published between 2010 and nowadays, tested on humans, which feature treatment based on needles with electrical stimulation in order to treat neuromusculoskeletal injuries. Study appraisal and synthesis methods: A quality assessment was performed according to the PEDro scale and reviewed the impact factor and quartile of the journal.

RESULTS

The treatment resulted in significant improvement in terms of pain intensity, pressure pain threshold, balance, muscular endurance, functionality/disability, subjective improvement, function of the descending pain modulatory system, and intake of drugs. Limitations: the lack of previous research studies on the subject and the lack of data on opioid intake in the selected studies.

CONCLUSION

Treatment based on PNM may be an alternative when treating injuries in soft tissues without significant side effects. However, there are few articles investigating the effects of PNM so more evidence is needed to draw solid conclusions.

Intramuscular Electrical Stimulation to Trigger Points: Insights into Mechanisms and Clinical Applications-A Scoping Review

Intramuscular electrical stimulation (IMES) is a modality used by clinicians to treat myofascial pain. Recent studies have shown positive results for the use of IMES on pain outcomes, yet studies investigating the potential mechanisms of IMES directly to trigger points (TrPs) are lacking. We performed a scoping review of the literature to summarize the current evidence from human and animal studies on the mechanisms of IMES to the TrP location, and to identify gaps in the existing literature. Electronic literature searches were conducted across five databases from inception to 15 August 2022, including PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Allied and Complementary Medicine Database (AMED), Scopus and Cochrane Register of Controlled Trials. Four studies met our full criteria for inclusion in this review. Three studies assessed the effects of IMES to TrPs on human subjects with MPS, and only one study used an animal model with experimentally generated TrPs. Based on the results of the included studies, IMES within a TrP region was reported to normalize muscle blood flow, decrease endplate noise of the TrP and elicit antinociceptive effects, at least partially, through engaging supraspinal descending pain inhibitory systems. At present, no clinical implications can be determined on the use of IMES to TrPs due to the limited amount and quality of the available evidence. Further studies investigating the clinical effectiveness and also underlying mechanisms of IMES to TrPs are clearly needed.

The efficacy of intramuscular electrical stimulation in the management of patients with myofascial pain syndrome: a systematic review

Introduction

Myofascial pain syndrome (MPS) is one of the most common disorders causing chronic muscle pain. Almost one-third of patients with musculoskeletal complaints meet the MPS criteria. The aim of this study is to evaluate the effectiveness of intramuscular electrical stimulation (IMES) in patients with MPS through a systematic review method.

Methods

PubMed, Scopus, Embase, ProQuest, PEDro, Web of Science, and CINAHL were systematically searched to find out the eligible articles without language limitations from 1990 to December 30, 2020. All relevant randomized controlled trials that compared the effectiveness of IMES with sham-IMES, dry needling, or exercise therapy in patients with MPS were included. Full texts of the selected studies were critically appraised using Revised Cochrane risk-of-bias tool for randomized trials (RoB2).

Results

Six studies (out of 397) had met our inclusion criteria (involving 158 patients) and were entered to the systematic review. Outcome measures examined in these studies included pain, range of motion, pressure pain threshold, biochemical factors, disability, and amount of analgesic use. In the most studies, it has been shown that IMES is more effective than the control group in improving some outcome measurements such as pain.

Conclusion

There is preliminary evidence from a few small trials suggesting the efficacy of IMES for the care of myofascial pain syndrome. The data support the conduct of larger trials investigating the efficacy of IMES.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12998-021-00396-z.

Rate and maintenance of improvement of myofascial pain with dry needling alone vs. dry needling with intramuscular electrical stimulation: a randomized controlled trial

STUDY DESIGN

Prospective, randomized.

OBJECTIVES

To determine the difference in rate and maintenance of improvement of pain and disability for Dry Needling (DN) compared to Dry Needling with Intramuscular Electrical Stimulation (DN/IMES), in Myofascial Pain Syndrome (MPS).

BACKGROUND

DN and neuromuscular electrical stimulation (NMES) have been shown to be efficacious in treating MPS. DN/IMES for MPS treatment has not been studied extensively, but initial results are promising.

METHODS

Forty-five subjects were randomly assigned to the DN (n = 25) or DN/IMES (n = 20) group. Both groups received six consecutive weekly treatments and completed NDI and NPRS questionnaires (week 0, 3, 6, and 12).

RESULTS

Both DN and DN/IMES groups showed significant improvement between weeks 0-6 on NDI (p = 0.008 and 0.00002, respectively) and NPRS scores (0 = 0.017 and p = 0.018, respectively). DN/IMES group showed significant within group changes on the NPRS between weeks 0-3 (p = 0.029). No changes were noted in the DN or DN/IMES groups between week 6-12 on NDI (p = 0.497 and p = 0.714, respectively) or NPRS (p = 0.801 and p = 0.164, respectively).

CONCLUSION

DN and DN/IMES demonstrated improvement and maintenance in disability and pain for 6 weeks. No differences in improvement of disability or pain existed between the groups at week 6 or 12.

Short-Term Effects of PENS versus Dry Needling in Subjects with Unilateral Mechanical Neck Pain and Active Myofascial Trigger Points in Levator Scapulae Muscle: A Randomized Controlled Trial

Procedures such as dry needling (DN) or percutaneous electrical nerve stimulation (PENS) are commonly proposed for the treatment of myofascial trigger points (MTrP). The aim of the present study is to investigate if PENS is more effective than DN in the short term in subjects with mechanical neck pain. This was an evaluator-blinded randomized controlled trial. Subjects were recruited through announcements and randomly allocated into DN or PENS groups. Pain intensity, disability, pressure pain threshold (PPT), range of motion (ROM), and side-bending strength were measured. The analyses included mixed-model analyses of variance and pairwise comparisons with Bonferroni correction. The final sample was composed of 44 subjects (22 per group). Both groups showed improvements in pain intensity (ηp2 = 0.62; p < 0.01), disability (ηp2 = 0.74; p < 0.01), PPT (ηp2 = 0.79; p < 0.01), and strength (ηp2 = 0.37; p < 0.01). The PENS group showed greater improvements in disability (mean difference, 3.27; 95% CI, 0.27-6.27) and PPT (mean difference, 0.88-1.35; p < 0.01). Mixed results were obtained for ROM. PENS seems to produce greater improvements in PPT and disability in the short term.

Effectiveness of percutaneous electrical nerve stimulation for musculoskeletal pain: A systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

To evaluate the effects of percutaneous electrical stimulation (PENS) alone or as an adjunct with other interventions on pain and related disability in musculoskeletal pain conditions.

DATABASES AND DATA TREATMENT

Search of MEDLINE, EMBASE, AMED, CINAHL, EBSCO, PubMed, PEDro, Cochrane Library, SCOPUS and Web of Science databases. Randomized controlled trials where at least one group received any form of PENS for musculoskeletal condition. Studies had to include humans and collect outcomes on pain and related disability in musculoskeletal pain. Risk of bias was assessed by the Cochrane Guidelines, the quality of evidence by using the GRADE approach. Standardized mean differences (SMD) were calculated.

RESULTS

Sixteen studies were included and included heterogeneous musculoskeletal conditions with short- or midterm follow-ups. PENS alone had a large effect (SMD -1.22, 95% CI -1.66 to -0.79) on pain and a small effect (SMD -0.33, 95% CI -0.61 to -0.06) on related disability at short-term as compared with sham. A moderate effect of PENS alone (SMD -0.71, 95% CI -1.23 to -0.19) on pain when compared with other interventions was observed. The inclusion of PENS with other interventions had a moderate effect for decreasing pain at short- (SMD -0.70, 95% CI -1.02 to -0.37) and midterm (SMD -0.68, 95% CI -1.10 to -0.27). No effect at midterm (SMD -0.21, 95% CI -0.52 to 0.10) on related disability was seen. The risk of bias was generally low; but the heterogenicity of the results downgraded the level of evidence.

CONCLUSION

There is low level of evidence suggesting the effects of PENS alone or in combination for pain, but not related disability, in musculoskeletal pain.

LEVEL OF EVIDENCE

Therapy, level 1a. Registration number: CRD42019131331.

SIGNIFICANCE

This meta-analysis investigating the effectiveness of PENS for the management of pain and related disability in musculoskeletal pain conditions found that PENS could decrease level of pain intensity but not relateddisability in musculoskeletal pain disorders.

Functional Spectroscopy Mapping of Pain Processing Cortical Areas During Non-painful Peripheral Electrical Stimulation of the Accessory Spinal Nerve

Peripheral electrical stimulation (PES), which encompasses several techniques with heterogeneous physiological responses, has shown in some cases remarkable outcomes for pain treatment and clinical rehabilitation. However, results are still mixed, mainly because there is a lack of understanding regarding its neural mechanisms of action. In this study, we aimed to assess its effects by measuring cortical activation as indexed by functional near infrared spectroscopy (fNIRS). fNIRS is a functional optical imaging method to evaluate hemodynamic changes in oxygenated (HbO) and de-oxygenated (HbR) blood hemoglobin concentrations in cortical capillary networks that can be related to cortical activity. We hypothesized that non-painful PES of accessory spinal nerve (ASN) can promote cortical activation of sensorimotor cortex (SMC) and dorsolateral prefrontal cortex (DLPFC) pain processing cortical areas. Fifteen healthy volunteers received both active and sham ASN electrical stimulation in a crossover study. The hemodynamic cortical response to unilateral right ASN burst electrical stimulation with 10 Hz was measured by a 40-channel fNIRS system. The effect of ASN electrical stimulation over HbO concentration in cortical areas of interest (CAI) was observed through the activation of right-DLPFC (p = 0.025) and left-SMC (p = 0.042) in the active group but not in sham group. Regarding left-DLPFC (p = 0.610) and right-SMC (p = 0.174) there was no statistical difference between groups. As in non-invasive brain stimulation (NIBS) top-down modulation, bottom-up electrical stimulation to the ASN seems to activate the same critical cortical areas on pain pathways related to sensory-discriminative and affective-motivational pain dimensions. These results provide additional mechanistic evidence to develop and optimize the use of peripheral nerve electrical stimulation as a neuromodulatory tool (NCT 03295370— www.clinicaltrials.gov).