Effects of spatially targeted transcutaneous electrical nerve stimulation using an electrode array that measures skin resistance on pain and mobility in patients with osteoarthritis in the knee: a randomized controlled trial

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.

Efficacy and safety of radiofrequency treatment for improving knee pain and function in knee osteoarthritis: a meta-analysis of randomized controlled trials

Background

The clinical utility of radiofrequency (RF) in patients with knee osteoarthritis (OA) remains unclear. We conducted a meta-analysis to systematically evaluate the efficacy and safety of RF treatment in patients with knee OA.

Methods

Searches of the PubMed, Web of Science, EMBASE, Cochrane Library, China National Knowledge Infrastructure, and Wanfang Data databases were performed through August 30, 2021. The major outcomes from published randomized controlled trials (RCTs) involving patients with knee OA were compared between RF and control groups, including Visual Analogue Scale (VAS) or Numerical Rating Scale (NRS) scores, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Oxford Knee Score (OKS), Global Perceived Effect (GPE) scale, and adverse effects at available follow-up times.

Results

Fifteen RCTs involving 1009 patients were included in this meta-analysis, and the results demonstrated that RF treatment correlated with improvements in pain relief (VAS/NRS score, all P < 0.001) and knee function (WOMAC, all P < 0.001) at 1–2, 4, 12, and 24 weeks after treatment as well as patients’ degree of satisfaction with treatment effectiveness (GPE scale, 12 weeks, P < 0.001). OKSs did not differ significantly between the two groups. Moreover, treatment with RF did not significantly increase adverse effects. Subgroup analysis of knee pain indicated that the efficacy of RF treatment targeting the genicular nerve was significantly better than intra-articular RF at 12 weeks after treatment (P = 0.03).

Conclusions

This meta-analysis showed that RF is an efficacious and safe treatment for relieving knee pain and improving knee function in patients with knee OA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-021-02906-4.

Resolving Long-Standing Uncertainty about the Clinical Efficacy of Transcutaneous Electrical Nerve Stimulation (TENS) to Relieve Pain: A Comprehensive Review of Factors Influencing Outcome

Pain is managed using a biopsychosocial approach and pharmacological and non-pharmacological treatments. Transcutaneous electrical nerve stimulation (TENS) is a technique whereby pulsed electrical currents are administered through the intact surface of the skin with the intention of alleviating pain, akin to 'electrically rubbing pain away'. Despite over 50 years of published research, uncertainty about the clinical efficacy of TENS remains. The purpose of this comprehensive review is to critically appraise clinical research on TENS to inform future strategies to resolve the 'efficacy-impasse'. The principles and practices of TENS are described to provide context for readers unfamiliar with TENS treatment. The findings of systematic reviews evaluating TENS are described from a historical perspective to provide context for a critical evaluation of factors influencing the outcomes of randomized controlled trials (RCTs); including sample populations, outcome measures, TENS techniques, and comparator interventions. Three possibilities are offered to resolve the impasse. Firstly, to conduct large multi-centered RCTs using an enriched enrolment with randomized withdrawal design, that incorporates a 'run-in phase' to screen for potential TENS responders and to optimise TENS treatment according to individual need. Secondly, to meta-analyze published RCT data, irrespective of type of pain, to determine whether TENS reduces the intensity of pain during stimulation, and to include a detailed assessment of levels of certainty and precision. Thirdly, to concede that it may be impossible to determine efficacy due to insurmountable methodological, logistical and financial challenges. The consequences to clinicians, policy makers and funders of this third scenario are discussed. I argue that patients will continue to use TENS irrespective of the views of clinicians, policy makers, funders or guideline panel recommendations, because TENS is readily available without prescription; TENS generates a pleasant sensory experience that is similar to easing pain using warming and cooling techniques; and technological developments such as smart wearable TENS devices will improve usability in the future. Thus, research is needed on how best to integrate TENS into existing pain management strategies by analyzing data of TENS usage by expert-patients in real-world settings.

Effect of Pressure on the Yinmen Point in Relief of Pain After Middle Ear Surgery: A Randomized Clinical Trial

Background

Postoperative pain is a common problem after middle ear surgery. Several analgesic agents are available for pain relief, but they cause numerous side effects. Therefore, complementary analgesic methods are developed to reduce patient’s postoperative pain and discomfort.

Objectives

The current study aimed to investigate the effect of the acupressure on post middle ear surgery pain, applying pressure on the Yinmen acupoint of the sciatic nerve.

Methods

In this randomized clinical trial, 100 adult patients who were candidate for elective middle ear surgery were selected and divided into two groups of Yinmen and placebo, each with 50 subjects. After admission to the ward, patients’ postoperative pain score was measured using the visual analog score (VAS) tool. Then, patients were placed in the prone position. In the Yinmen group, using a fist, we applied a continuous pressure (11 - 20 kg) to the posterior aspect of the thighs at the Yinmen acupoint for 2 minutes. In the placebo group, only soft contact was kept between the fist and Yinmen point for the same period. The maneuver repeated every two hours for four times. The pain intensity surveyed 10 minutes after the first maneuver, then every hour for 8 hours. For those with a VAS score ≥ 4, intravenous paracetamol and/or meperidine was administered. Any nausea and vomiting was managed using ondansetron 2 mg, IV. The pain score, paracetamol, and meperidine consumption were recorded and compared between the two groups. The chi-square and student t-tests were used to compare the two groups.

Results

No significant difference was found between patients’ characteristics and the first pain score. For all measurements, pain intensity was lower in the Yinmen group (P value < 0.01). The pain after the first maneuver was relieved exactly when the acupressure was true. The intervention could reduce patients’ need to take paracetamol (6.68 ± 2.58 vs. 10.42 ± 3.87 mg/kg) and meperidine (0.21 ± 0.17 vs. 0.39 ± 0.23 mg/kg) in the Yinmen group. The two groups were not significantly different concerning the need to take ondansetron to manage postoperative nausea and vomiting.

Conclusions

Applying 2 minutes pressure (11 - 20 kg) on the Yinmen acupoint of the sciatic nerves can reduce post middle ear surgery pain and analgesic consumption.

[Physical therapy options in rheumatic diseases: what is evidence-based?]

Rheumatic diseases usually progress towards morphological and functional deficits and thus cause impairment of physical health and function. Based on this fact, physiotherapeutic options are elementary and indispensable. This article focuses on the significance and importance of physiotherapy in inflammatory and degenerative rheumatic diseases. Furthermore, an overview is presented on the consequences of rheumatic diseases, the reality of supply of physiotherapy, the principles and therapeutic options, and the evidence.

Phisical modalities on the functional performance in knee osteoarthritis: a sytematic review

Abstract Introduction: Despite recent advances in the treatment of osteoarthritis (OA), few studies have evaluated the longitudinal effect of physical modalities in functional capacity in patients with knee OA. Thereby, since the physical components and pain can affect the functional performance of daily activities, the effect of these treatment’s form is still to be established. Objective: Evaluate the effectiveness of therapeutic ultrasound, electrical stimulation and phototherapy in the functional performance, in patients with knee osteoarthritis. Methods: Articles present in the PubMed, Lilacs, SciELO and PEDro’s databases were evaluated. The used keywords were “pulsed ultrasound therapy”, “ultrasound therapy”, “electric stimulation” and “low level laser therapy” in combination with “knee osteoarthritis”. Were included in this presented review, randomized clinical studies using ultrasound, electrical and laser stimulation in subjects with knee osteoarthritis. To evaluate the methodological quality of the selected studies, was used the PEDro’s scale. The dependent variables of the study were: pain, physical function, joint stiffness, life quality and functional performance. Results: 268 studies were found, of these, 41 studies met eligibility criteria and were classified for analysis in full. The used methodology in the studies varied widely, however, in most cases there was improvement in functional performance of individuals with knee OA, with the use of physical modalities, for the pulsed ultrasound, continuous ultrasound, electrical stimulation and laser resourses. Conclusion: The physical modalities used in the studies demonstrated improvement in functional performance of individuals with knee OA.

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.

The effect of adding whole body vibration training to strengthening training in the treatment of knee osteoarthritis: A randomized clinical trial

Strengthening training (ST) and whole body vibration training (WBV) alone may improve symptoms of osteoarthritis of the knee. In this study, we investigated the effect of adding WBV training to quadriceps and hamstring muscles strengthening training on functional activity, pain, quality of life and muscle strength in patients with knee osteoarthritis. 28 volunteers were randomly allocated to two groups; 1) quadriceps and hamstring muscles strengthening training (ST group, 13 patients) and 2) quadriceps and hamstring muscles strengthening training along with WBV training (ST + WBV group, 15 patients). The treatment protocol for both groups involved 3 sessions per week for 8 weeks. All measurements were performed before and after intervention. The measurements included: pain by means of a visual analogue scale (VAS), quality of life by means of the WOMAC scale, functional activity by the 2 min walking test (2MWT), time up & go test (TUGT) and 50-foot walking test (50FWT) and the muscle peak torque (MPT), total work (TW) and muscle power (MP) as muscle performance of quadriceps and hamstring muscles by an Isokinetic Biodex machine. After intervention, the comparison of mean changes between two groups showed improvement in the WBV + ST group in terms of 2MWT, MPT, TW and MP variables (P < 0.05). However, no significant difference was found between the experimental groups in term of pain, quality of life, TUGT and 50FWT. These results suggest that adding whole body vibration training to strengthening training may provide better treatment effects for patients with knee osteoarthritis.

Electromechanical method coupling non-invasive skin impedance probing and in vivo subcutaneous liquid microinjection: controlling the diffusion pattern of nanoparticles within living soft tissues

Transdermal drug delivery is the way to transport drug carriers, such as nanoparticles, across the skin barrier to the dermal and/or subcutaneous layer. In order to control the transdermal drug delivery process, based on the heterogeneous and nonlinear structures of the skin tissues, we developed a novel electromechanical method combining in vivo local skin impedance probing, subcutaneous micro-injection of colloidal nanoparticles, and transcutaneous electrical stimulation. Experiments on the nude mice using in vivo fluorescence imaging exhibited significantly different apparent diffusion patterns of the nanoparticles depending on the skin impedance: Anisotropic and isotropic patterns were observed upon injection into low and high impedance points, respectively. This result implies that the physical complexity in living tissues may cause anisotropic diffusion of drug carriers, and can be used as a parameter for controlling drug delivery process. This method also can be combined with microneedle-based drug release systems, micro-fabricated needle-electrodes, and/or advanced in vivo targeting/imaging technologies using nanoparticles.

Transcutaneous electrical nerve stimulation attenuates CFA-induced hyperalgesia and inhibits spinal ERK1/2-COX-2 pathway activation in rats

BACKGROUND

Transcutaneous electrical nerve stimulation (TENS) is a non-pharmacologic treatment for pain relief. In previous animal studies, TENS effectively alleviated Complete Freund's Adjuvant (CFA)- or carrageenan-induced inflammatory pain. Although TENS is known to produce analgesia via opioid activation in the brain and at the spinal level, few reports have investigated the signal transduction pathways mediated by TENS. Prior studies have verified the importance of the activation of extracellular signal-regulated kinase (ERK) signal transduction pathway in the spinal cord dorsal horn (SCDH) in acute and persistent inflammatory pains. Here, by using CFA rat model, we tested the efficacy of TENS on inhibiting the expressions of p-ERK1/2 and of its downstream cyclooxygenase-2 (COX-2) and the level of prostaglandin E2 (PGE2) at spinal level.

METHODS

Rats were randomly divided into control, model and TENS groups, and injected subcutaneously with 100 μl CFA or saline in the plantar surface of right hind paw. Rats in the TENS group were treated with TENS (constant aquare wave, 2 Hz and 100 Hz alternating frequencies, intensities ranging from 1 to 2 mA, lasting for 30 min each time) at 5 h and 24 h after injection. Paw withdrawal thresholds (PWTs) were measured with dynamic plantar aesthesiometer at 3d before modeling and 5 h, 6 h, and 25 h after CFA injection. The ipsilateral sides of the lumbar spinal cord dosral horns were harvested for detecting the expressions of p-ERK1/2 and COX-2 by western blot analysis and qPCR, and PGE2 by ELISA.

RESULTS

CFA-induced periphery inflammation decreased PWTs and increased paw volume of rats. TENS treatment significantly alleviated mechanical hyperalgesia caused by CFA. However, no anti-inflammatory effect of TENS was observed. Expression of p-ERK1/2 protein and COX-2 mRNA was significantly up-regualted at 5 h and 6 h after CFA injection, while COX-2 and PGE2 protein level only increased at 6 h after modeling. Furthermore, the high expression of p-ERK1/2 and COX-2, and over-production of PGE2 induced by CFA, were suppressed by TENS administration.

CONCLUSIONS

TENS may be an effective therapy in controlling inflammatory pain induced by CFA. Its analgesic effect may be associated with the inhibition of activation of the spinal ERK1/2-COX-2 pathway.