Comparative Efficacy of Low-Level Laser Therapy in Patients With Carpal Tunnel Syndrome: An Updated Systematic Review and Meta-analysis of Randomized Controlled Trials

Objective: To evaluate the effects of low-level laser therapy (LLLT) on clinical and physiological outcomes in carpal tunnel syndrome (CTS) and identify key treatment moderators. Design: Following PRISMA 2020, six databases were searched through December 2025. The primary outcome was pain; secondary outcomes were grip strength, median nerve cross-sectional area (CSA), sensory nerve conduction velocity (SNCV) and sensory distal latency (SDL). Subgroup and meta-regression analyses examined regimens, emission modes, and session numbers. Results: Sixteen randomized controlled trials were analyzed. LLLT significantly reduced pain (Hedges’ g =-1.524, P <0.001) and improved grip strength (Hedges’ g =0.391, P =0.002). Pulsed mode was superior for analgesia, whereas continuous mode better supported grip strength. SNCV improved significantly (Hedges’ g =0.377, P =0.016), with benefits primarily associated with LLLT used adjunctively with active conservative treatment (ACT) or delivered in pulsed mode; CSA reduction was not significant overall ( P =0.064) and was significant only in the ACT subgroup. Meta-regression identified session number and wavelength as significant moderators for certain outcomes. Conclusion: LLLT effectively manages CTS, with parameter-dependent outcomes. Pulsed mode enhances analgesia, whereas continuous mode favors functional recovery. Protocols should tailor laser parameters to therapeutic targets.