Effectiveness of low-level laser therapy in the rehabilitation of knee meniscus injuries: a randomized, double-blind, placebo-controlled trial

Abstract

To evaluate the effectiveness of low-level laser therapy (LLLT) as an adjunct to rehabilitation in reducing pain and improving knee function in adults with MRI-confirmed meniscus injuries. In this randomized, double-blind, placebo-controlled trial, 40 adults with unilateral meniscus injuries were assigned to either an LLLT group or a placebo group. All participants received a standardized rehabilitation program over six weeks. The primary outcome was pain intensity measured using a visual analogue scale (VAS). Secondary outcomes included knee function (Lysholm score), range of motion (ROM), and physical performance tests. Both groups showed significant improvements; however, the LLLT group demonstrated greater reductions in pain and improvements in function, mobility, and ROM compared with the control group (p < 0.01 for all outcomes). The magnitude of improvement exceeded clinically meaningful thresholds, particularly for pain reduction and functional gains. Adjunctive LLLT was associated with greater improvements in pain and functional outcomes compared with rehabilitation alone. LLLT appears to be a safe and potentially effective complementary modality in the conservative management of meniscal injuries.