Laser acupuncture (LA) has been increasingly investigated as a non-invasive therapy for knee osteoarthritis (KOA), yet its clinical efficacy remains uncertain. To evaluate the effectiveness and safety of LA for pain, function, and mobility in KOA through a systematic review and meta-analysis. Randomized controlled trials (RCTs) comparing LA with sham, placebo, electroacupuncture, or standard care were identified from major databases. Outcomes included pain (VAS, WOMAC-Pain, NPRS, PI), function (WOMAC-Function), and range of motion (flexion). Risk of bias was assessed using RoB 2, and heterogeneity explored through subgroup analyses. Thirteen RCTs of 611 participants were included. LA did not significantly improve WOMAC pain (SMD 0.04; 95% CI - 0.36 to 0.45), pVAS (SMD 0.12; 95% CI - 0.91 to 1.15), or NPRS (SMD - 0.23; 95% CI - 0.58 to 0.12). Function showed a nonsignificant trend toward improvement (SMD - 0.32; 95% CI - 0.94 to 0.30), and knee flexion outcomes were also nonsignificant (SMD 0.10; 95% CI - 0.39 to 0.59). Substantial heterogeneity (I² > 70%) was observed across studies, likely related to differences in wavelength (650-904 nm), dosage, and acupoint protocols. Funnel plots did not suggest marked publication bias. Current evidence does not demonstrate statistically significant benefits of LA over comparators for pain, function, or flexion in KOA. Considerable heterogeneity and variability in laser parameters limit firm conclusions. Large, standardized RCTs with optimized parameters are needed to confirm efficacy and guide clinical application.Clinical trial number: Not applicable.
Kamau et al. (Fri,) studied this question.