Efficacy of prolonged application of low-level laser therapy combined with exercise in knee osteoarthritis: A randomized controlled double-blind study.

OBJECTIVES: To investigate the effect of prolonged low-level laser therapy application combined with exercise on pain and disability in patients with osteoarthritis of the knee. DESIGN: A randomized controlled trial. SETTING: Special rehabilitation services. SUBJECTS: Forty-three participants with knee osteoarthritis. INTERVENTION: Following initial assessment, participants were randomly allocated to the Laser group (n = 22, 44 knees) and received low-level laser therapy while the Placebo group (n = 21, 42 knees) received placebo therapy three times a week for 3 weeks. Both groups then received low-level laser therapy combined with exercise three times a week for the following 8 weeks. MAIN OUTCOME MEASURES: The primary outcome was change in knee pain and disability (Lequesne). Secondary outcomes included change in mobility (Timed Up and Go test), range of motion (goniometer), muscular strength (dynamometer), activity (Western Ontario and McMaster Universities Osteoarthritis questionnaire), and medication intake and relief. RESULTS: Mean (SD) age of participants was 63.02 (9.9) years. Pain scores at baseline, 3 weeks, 11 weeks, and 6 months follow-up were 9.1 (1.3), 2.6 (2.3), 0.2 (0.9), and 0.2 (0.8) for the Laser group and 9.5 (8.0), 7.7 (5.3), 5.6 (2.4), and 7.4 (5.0) for the Placebo group, respectively. Disability scores at baseline, 3 weeks, 11 weeks, and 6 months follow-up were 14.9 (4.7), 7.6 (4.8), 3.9 (4.2), and 3.5 (4.1) for the Laser group and 17.8 (14.7), 15.2 (11.5), 11.6 (6.4), and 15.8 (11.9) for the Placebo Group, respectively. CONCLUSION: In participants with osteoarthritis of the knee, the isolated application of low-level laser therapy in the initial 3 weeks and combined with exercises in the final 8 weeks reduced pain, disability, and intake of medication over a 6-month period.