A randomized double-blinded controlled trial on the effects of photobiomodulation therapy in dogs with osteoarthritis

OBJECTIVE To evaluate photobiomodulation therapy in dogs with bilateral hip osteoarthritis. ANIMALS 20 dogs. PROCEDURES Forty joints were assigned to a control group (CG; n = 20) or treatment group (photobiomodulation therapy [PBMT]; 20). CG received a 21-day course of meloxicam, and PBMT received treatment with a Class IV therapeutic laser over 3 weeks. Joint range of motion, thigh girth, the Canine Brief Pain Inventory (divided into pain interference score [PIS] and pain severity score [PSS]), Hudson Visual Analogue Scale, Liverpool Osteoarthritis in Dogs, and Canine Orthopedic Index (COI; divided into function, gait, stiffness, and quality of life) were evaluated before treatment, +8, +15, +30, +60, and +90 days after initial treatment. Results were analyzed with repeated measures ANOVA or Wilcoxon signed ranks test, P < 0.05. Kaplan-Meier estimators were compared with the Breslow test. RESULTS Patients had a mean age of 8.3 +/- 1.9 years and body weight of 65.7 +/- 12.1lb. Osteoarthritis was classified as moderate (n = 26) and severe (14). No differences were found at time 0. Better results were observed in PBMT at +8 days (P = 0.01 for PSS, P = 0.04 for function and COI), +15 days (P = 0.01 for PSS and function, P = 0.02 for PIS and function, P = 0.03 for COI and P = 0.04 for Liverpool Osteoarthritis in Dogs [LOAD]) and +30 days (P = 0.01 for function and gait, P = 0.02 for COI, and P = 0.04 for PIS, PSS, and LOAD). Joint range of motion improved in PBMT from +15 to 90 days. Kaplan-Meier estimators showed that PBMT produced longer periods with better results. CLINICAL RELEVANCE PBMT reduced pain levels and improved clinical findings in dogs with hip osteoarthritis.