Influence of Percutaneous Microelectrolysis in the Upper Trapezius on Pressure Pain Threshold and Surface Electromyography: A Randomized Sham-Controlled Pilot Trial
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Abstract
Background: Myofascial pain syndrome is a non-inflammatory disorder that manifests as referred pain and stiffness, with its primary feature being the presence of myofascial trigger points (MTrP). Several methods exist to treat this syndrome, and one of the earliest described techniques involves the invasive use of direct current.
Study design: A randomized, double-blind, sham-controlled pilot trial.
Participants: Adults (18–48 years) with active myofascial trigger points (MTrPs) in the upper trapezius were recruited. Exclusion criteria included prior shoulder or neck surgery, fibromyalgia, anticoagulant use, pregnancy, or BMI > 28 kg/m².
Interventions: Participants were randomly allocated to a low-intensity galvanic current group or a sham group. The active group received static percutaneous microelectrolysis with a 0.3 × 25 mm acupuncture needle and current intensities ranging from 0.12 mA to 0.6 mA (2.53 mA/cm²) for three 60-second cycles. In the sham group, the needle was inserted superficially (up to 3 mm) over the upper trapezius region without reaching the muscle, and no electrical current was applied.
Objectives: To compare the effects of low-intensity galvanic current on pressure pain threshold levels and electromyographic pattern (basal and peak) in individuals with myofascial trigger points in the upper trapezius muscle.
Materials and Methods: Pressure pain threshold (PPT) and surface electromyographic (EMG) (basal and isometric peak and RMS) were measured at baseline, 1 minute, and 10 minutes post-intervention. Independent-sample t-tests and effect sizes (Cohen’s d) were calculated (p < 0.05).
Results: Sixteen participants were randomized, with eight allocated to each group. No statistically significant differences were observed between groups for PPT or EMG variables. However, medium effect sizes were observed for resting and isometric root mean square (RMS) EMG activity at 1 minute post-intervention, and a large effect size for resting peak EMG activity at 1 minute.
Conclusions: In this pilot trial, no statistically significant between-group differences were observed. Although moderate-to-large effect sizes were observed for some EMG variables immediately post-intervention, these results should be interpreted cautiously. Larger trials with longer follow-up are needed.
Keywords
- galvanic current
- pain
- surface electromyography
References
David G. Simons, Janet G. Travell, Lois S. Simons. Myofascial Pain and Dysfunction: The Trigger Point Manual. Baltimore MD, editor. Lippincott Williams & Wilkins; 1998.
Zhai T, Jiang F, Chen Y, Wang J, Feng W. Advancing musculoskeletal diagnosis and therapy: a comprehensive review of trigger point theory and muscle pain patterns. Front Med (Lausanne). 2024;11. https://doi.org/10.3389/fmed.2024.1433070
Cao Q-W, Peng B-G, Wang L, Huang Y-Q, Jia D-L, Jiang H, et al. Expert consensus on the diagnosis and treatment of myofascial pain syndrome. World J Clin Cases. 2021;9:2077–89. https://doi.org/10.12998/wjcc.v9.i9.2077
Li L, Stoop R, Clijsen R, Hohenauer E, Fernández-de-las-Peñas C, Huang Q, et al. Criteria Used for the Diagnosis of Myofascial Trigger Points in Clinical Trials on Physical Therapy. Clin J Pain. 2020;36:955–67. https://doi.org/10.1097/AJP.0000000000000875
Cojocaru MC, Cojocaru IM, Voiculescu VM, Cojan-Carlea NA, Dumitru VL, Berteanu M. Trigger points--ultrasound and thermal findings. J Med Life. 2015;8:315–8. PMID: 26351532.
Quintner JL, Bove GM, Cohen ML. A critical evaluation of the trigger point phenomenon. Rheumatology. 2015;54:392–9. https://doi.org/10.1093/rheumatology/keu471
Shah JP, Thaker N, Heimur J, Aredo J V., Sikdar S, Gerber L. Myofascial Trigger Points Then and Now: A Historical and Scientific Perspective. PM&R. 2015;7:746–61. https://doi.org/10.1016/j.pmrj.2015.01.024
Fernández-de-las-Peñas C, Dommerholt J. International Consensus on Diagnostic Criteria and Clinical Considerations of Myofascial Trigger Points: A Delphi Study. Pain Medicine. 2018;19:142–50. https://doi.org/10.1093/pm/pnx207
Geri T, Botticchio A, Rossettini G, Pournajaf S, Pellicciari L, Di Antonio S, et al. Pressure Pain Threshold of the Upper Trapezius Trigger Point: A Systematic Review with Meta-Analysis of Baseline Values and Their Modification after Physical Therapy. J Clin Med. 2022;11:7243. https://doi.org/10.3390/jcm11237243
Castaldo M, Catena A, Fernández-de-las-Peñas C, Arendt-Nielsen L. Widespread Pressure Pain Hypersensitivity, Health History, and Trigger Points in Patients with Chronic Neck Pain: A Preliminary Study. Pain Medicine. 2019;20:2516–27. https://doi.org/10.1093/pm/pnz035
Fernández-de-las-Peñas C, Dommerholt J. International Consensus on Diagnostic Criteria and Clinical Considerations of Myofascial Trigger Points: A Delphi Study. Pain Medicine. 2018;19:142–50. https://doi.org/10.1093/pm/pnx207
Park G, Kim CW, Park SB, Kim MJ, Jang SH. Reliability and Usefulness of the Pressure Pain Threshold Measurement in Patients with Myofascial Pain. Ann Rehabil Med. 2011;35:412. https://doi.org/10.5535/arm.2011.35.3.412
Perreault T, Ball A, Dommerholt J, Theiss R, Fernández-de-las-Peñas C, Butts R. Intramuscular Electrical Stimulation to Trigger Points: Insights into Mechanisms and Clinical Applications—A Scoping Review. J Clin Med. 2022;11:6039. https://doi.org/10.3390/jcm11206039
Lara-Palomo IC, Antequera-Soler E, Fernández-Sánchez M, Castro-Sánchez AM, García-López H. Electrical dry needling versus a non-invasive multicomponent intervention in the treatment of myofascial trigger points in patients with chronic low back pain: A randomised clinical trial. Clin Rehabil. 2024;38:347–60. https://doi.org/10.1177/02692155231201589
Dommerholt J, Mayoral O, Thorp JN. A critical overview of the current myofascial pain literature – January 2021. J Bodyw Mov Ther. 2021;25:261–71. https://doi.org/10.1016/j.jbmt.2020.12.044
Alayat MSM, Battecha KH, Elsodany AM, Alzahrani OA, Alqurashi AKA, Jawa AT, et al. Effectiveness of Photobiomodulation Therapy in the Treatment of Myofascial Pain Syndrome of the Upper Trapezius Muscle: A Systematic Review and Meta-Analysis. Photobiomodul Photomed Laser Surg. 2022;40:661–74. https://doi.org/10.1089/photob.2022.0056
Johnson MI, Paley CA, Jones G, Mulvey MR, Wittkopf PG. Efficacy and safety of transcutaneous electrical nerve stimulation (TENS) for acute and chronic pain in adults: a systematic review and meta-analysis of 381 studies (the meta-TENS study). BMJ Open. 2022;12:e051073. https://doi.org/10.1136/bmjopen-2021-051073
Ortiz H, Cancino J, Peña FS, León FS, Donoso EM, Gaete VT. Effectiveness of percutaneous microelectrolysis and ultrasound in the decrease of pain in myofascial trigger points: evaluation through algometry and visual analog scale. Physiotherapy Quarterly. 2020;28:1–8. https://doi.org/10.5114/pq.2020.95768
De-la-Cruz-Torres B, Romero-Rodríguez B, Romero-Morales C. Ultrasound-Guided Percutaneous Needle Electrolysis Combined With Therapeutic Exercise May Add Benefit in the Management of Soleus Injury in Female Soccer Players: A Pilot Study. J Sport Rehabil. 2022;1–7. https://doi.org/10.1123/jsr.2022-0021
Ronzio OA, da Silva Coldibeli E, Soares Fernandes MDR, Froes Meyer P, da Silva RM V. Effects of percutaneous microelectrolysis (MEP ® ) on pain, rom and morning stiffness in patients with achilles tendinopathy. Eur J Physiother. 2017;19:62–3. https://doi.org/10.1080/21679169.2017.1381321
d’Almeida SM, Silva RMV da, Ronzio OA. Nivel de satisfacción sobre la seguridad y complicaciones a cuatro años de la introducción de la técnica Microelectrólisis Percutánea (MEP®) Sport como práctica fisioterapéutica. Fisioterapia e Pesquisa. 2019;26:190–5. https://doi.org/10.1590/1809-2950/18038726022019
Lluch E, Nijs J, De Kooning M, Van Dyck D, Vanderstraeten R, Struyf F, et al. Prevalence, Incidence, Localization, and Pathophysiology of Myofascial Trigger Points in Patients With Spinal Pain: A Systematic Literature Review. J Manipulative Physiol Ther. 2015;38:587–600. https://doi.org/10.1016/j.jmpt.2015.08.004
Hopewell S, Chan A-W, Collins GS, Hróbjartsson A, Moher D, Schulz KF, et al. CONSORT 2025 explanation and elaboration: updated guideline for reporting randomised trials. BMJ. 2025;e081124. https://doi.org/10.1136/bmj-2024-081124
Costa LOP, Christine Lin C-W, Grossi DB, Mancini MC, Swisher AK, Cook C, et al. Clinical trial registration in physiotherapy journals: Recommendations from the International Society of Physiotherapy Journal Editors. Man Ther. 2013;18:1–3. https://doi.org/10.1016/j.math.2012.10.009
Gerwin RD, Shannon S, Hong C-Z, Hubbard D, Gevirtz R. Interrater reliability in myofascial trigger point examination. Pain. 1997;69:65–73. https://doi.org/10.1016/S0304-3959(96)03248-4
de la Barra Ortiz HA, Chamorro C, Ronzio Ó. Percutaneous electrolysis and microelectrolysis for musculoskeletal pain management: milliamps or microamps? An evidence-based comparison through systematic review and meta-analysis. Advances in Rehabilitation. 2024;38:36–60. https://doi.org/10.5114/areh.2024.141103
Lenhard, W. & Lenhard, A. (2022). Computation of effect sizes. Retrieved from: https://www.psychometrica.de/effect_size.html. Psychometrica. https://doi.org/10.13140/RG.2.2.17823.92329
Cohen J. A power primer. Psychol Bull. 1992;112:155–9. https://doi.org/10.1037/0033-2909.112.1.155
Rodríguez-Sanz J, Rodríguez-Rodríguez S, López-de-Celis C, Malo-Urriés M, Pérez-Amodio S, Pérez-Antoñanzas R, et al. Biological and Cellular Effects of Percutaneous Electrolysis: A Systematic Review. Biomedicines. 2024;12:2818. https://doi.org/10.3390/biomedicines12122818
Sluka KA, Frey-Law L, Hoeger Bement M. Exercise-induced pain and analgesia? Underlying mechanisms and clinical translation. Pain. 2018;159:S91–7. https://doi.org/10.1097/j.pain.0000000000001235
Raja SN, Carr DB, Cohen M, Finnerup NB, Flor H, Gibson S, et al. The revised International Association for the Study of Pain definition of pain: concepts, challenges, and compromises. Pain. 2020;161:1976–82. https://doi.org/10.1097/j.pain.0000000000001939
Turner JA, Arendt-Nielsen L. Four decades later: what’s new, what’s not in our understanding of pain. Pain. 2020;161:1943–4. https://doi.org/10.1097/j.pain.0000000000001991
Ronzio OA, Villa CA, Gómez D, Valentim da Silva RM, Gill JP, d’Almeida S, et al. Effects in pressure-pain threshold of percutaneous galvanic microcurrent in the trapezius trigger points. Physiotherapy. 2015;101:e1297–8. https://doi.org/10.1016/j.physio.2015.03.1214
García Bermejo P, de la Cruz Torres B, Naranjo Orellana J, Albornoz Cabello M. Autonomic activity in women during percutaneous needle electrolysis. Eur J Integr Med. 2017;11:53–8. https://doi.org/10.1016/j.eujim.2017.02.002
Fakontis C, Iakovidis P, Lytras D, Kasimis K, Koutras G, Ntinou SR, et al. Efficacy of percutaneous needle electrolysis versus dry needling in musculoskeletal pain: A systematic review and meta-analysis. J Back Musculoskelet Rehabil. 2023;36:1033–46. https://doi.org/10.3233/BMR-220408
Silva ACT da, Kamonseki DH, Azevedo LMV de, Araújo JN de, Magalhães GC, Oliveira VMA de. Effect of percutaneous electrolysis on pain and disability in individuals with tendinopathy: Systematic review and meta-analysis. J Bodyw Mov Ther. 2024;40:640–9. https://doi.org/10.1016/j.jbmt.2024.05.030
Faria BSF, Gonçalves JS, Sato T de O. Association between psychosocial factors in workers and multisite pain: cross-sectional study. Brazilian Journal Of Pain. 2022;5. https://doi.org/10.5935/2595-0118.20220002
Roomes D, Abraham L, Russell R, Beck C, Halsby K, Wood R, et al. Quantifying the Employer Burden of Persistent Musculoskeletal Pain at a Large Employer in the United Kingdom. J Occup Environ Med. 2022;64:e145–54. https://doi.org/10.1097/JOM.0000000000002468
Blyth FM, Briggs AM, Schneider CH, Hoy DG, March LM. The Global Burden of Musculoskeletal Pain—Where to From Here? Am J Public Health. 2019;109:35–40. https://doi.org/10.2105/AJPH.2018.304747
Ferreira MHL, Araujo GAS, De-La-Cruz-Torres B. Effectiveness of Percutaneous Needle Electrolysis to Reduce Pain in Tendinopathies: A Systematic Review With Meta-Analysis. J Sport Rehabil. 2024;33:307–16. https://doi.org/10.1123/jsr.2024-0009
Magalhães GC, Kamonseki DH, da Silva ACT, Nunes JA, de Sousa AIAF, Ribeiro DC, et al. Effectiveness of Microelectrolysis Associated With Exercises Versus Exercises Alone on Pain Intensity and Disability in Individuals With Chronic Rotator Cuff Tendinopathy: A Randomized Controlled Trial. Arch Phys Med Rehabil. 2024; https://doi.org/10.1016/j.apmr.2024.10.016
Girasol CE, Durán NE, D’Almeida SM, Ronzio OA. Toward an algorithm of percutaneous microelectrolysis: a randomized clinical trial on invasive techniques. Sao Paulo Medical Journal. 2025;143. https://doi.org/10.1590/1516-3180.2024.0164.r1.07032025
Sánchez-González JL, Navarro-López V, Cañada-Sánchez P, Juárez-Vela R, Viñaspre-Hernández RR de, Varela-Rodríguez S. Efficacy of different intensities of percutaneous electrolysis for musculoskeletal pain: A systematic review and meta-analysis. Front Med (Lausanne). 2023;10. https://doi.org/10.3389/fmed.2023.1101447
Yildizgoren MT, Bagcier F. A modern interpretation of traditional galvanic current: percutaneous needle electrolysis therapy. Acupuncture in Medicine. 2024;42:56–7. https://doi.org/10.1177/09645284231210569
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