Low-level laser therapy in meniscal pathology: a double-blinded placebo-controlled trial

Abstract

We performed a randomized, double-blinded, placebo-controlled study (ISRCTN24203769) to assess the effectiveness of low-level laser therapy (LLLT) in patients with meniscal pathology, including only symptomatic patients with tiny focus of grade 3 attenuation (seen only on 0.7 thickness sequences) or intrasubstance tears with spot of grade 3 signal intensity approaching the articular surface. None of the patients in the study group underwent arthroscopy or new magnetic resonance imaging investigation. Paired-samples t test was used to detect significant changes in subjective knee pain over the experimental period within groups, and ANOVA was used to detect any significant differences between the two groups. Pain was significantly improved for the LLLT group than for the placebo group (F = 154, p < 0.0001). Pain scores were significantly better after LLLT. Four (12.5%) patients did not respond to LLLT. At baseline, the average Lysholm score was 77 ± 4.6 for the LLLT group and 77.2 ± 2.6 for the placebo group (p > 0.05). Four weeks after LLLT or placebo therapy, the laser group reported an average Lysholm score of 82.5 ± 4.6, and the placebo group scored 79.0 ± 1.9. At 6months, the laser group had an average Lysholm score of 82.2 ± 5.7, and after 1year, they scored 81.6 ± 6.6 (F = 14.82923, p = 0.002). Treatment with LLLT was associated with a significant decrease of symptoms compared to the placebo group: it should be considered in patients with meniscal tears who do not wish to undergo surgery.