Abstract
BACKGROUND: Percutaneous microelectrolysis (MEP) is a minimally invasive technique used for pain relief, inflammation control, and tissue repair. However, the optimal treatment protocol remains under debate. OBJECTIVE: To compare the effects of dry needling and MEP, with and without a treatment algorithm, on pain in individuals with active myofascial trigger points (MTrPs) in the upper trapezius muscle. Design and setting: Randomized controlled trial conducted at Maimónides University, Buenos Aires. METHODS: Eighty-eight participants with MTrPs in the upper trapezius muscle were enrolled. The presence of MTrPs was confirmed through physical examination and algometric measurement before intervention. Participants were randomly assigned to one of six groups: Sham, dynamic dry needling, static dry needling, dynamic MEP, static MEP, or algorithmic MEP. Active treatments were administered using 0.30 mm × 40 mm acupuncture needles. Pain was assessed using two tools: the Numerical Pain Rating Scale (NPRS) and the Pressure Pain Threshold (PPT). Both measures were recorded with participants at rest before the intervention and again at 10 min, 24 h, 48 h, and 7 days post-intervention. RESULTS: Significant post-intervention differences in NPRS scores were observed in all groups except dynamic dry needling when compared to Sham. The algorithmic MEP group achieved complete pain relief by day 7. In terms of PPT, the threshold values in the MEP groups were lower than those in the other groups. CONCLUSIONS: All needling techniques demonstrated analgesic effects on myofascial trigger points, with the algorithm-enhanced MEP showing the most notable improvement in self-reported pain. However, MEP was not superior to other methods in improving pressure pain thresholds. CLINICAL TRIALS: NCT05478928.