Efficacy of high-intensity laser therapy versus ultrasound therapy in patients with knee osteoarthritis: a randomized controlled trial.

PURPOSE: High-intensity laser therapy (HILT) and ultrasound (US) are widely used for knee osteoarthritis (KOA), but comparative efficacy data remain scarce. This study compared HILT and US as exercise adjuncts in patients with KOA. METHODS: In this single-center, assessor-blinded RCT, 66 adults with KOA were randomized 1:1 to HILT or US twice weekly for 6 weeks as exercise adjuncts. The primary outcome was WOMAC total score change from baseline to 12 weeks post-treatment (minimum important change [MIC] = 10 points, applied as an approximation). Secondary outcomes included VAS, OKS, KOOS, and EQ-5D-5L. RESULTS: In ITT analysis (N = 66), the HILT group achieved a mean WOMAC reduction of 40.0 vs 8.2 points (adjusted between-group difference: -27.7 points, 95% CI: - 39.0 to - 16.5; p < 0.001, partial η2 = 0.277). At 12 weeks post-treatment, greater improvements across all secondary outcomes were observed in exploratory analyses (p ≤ 0.012). Furthermore, HILT maintained therapeutic effects up to 12 weeks post-treatment, whereas the US group experienced a gradual loss of post-treatment gains. CONCLUSION: HILT combined with exercise produced greater short-term improvements in WOMAC total score than US in patients with KOA, with exploratory findings suggesting consistent benefits in pain, function, and quality of life, and with benefits maintained up to 12 weeks after the last treatment session.