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Published on: March 18, 2014
A randomized double-blinded controlled trial on the effects of photobiomodulation therapy in dogs with osteoarthritis
João C Alves1,2, Ana Santos1, Patrícia Jorge1
1Divisão de Medicina Veterinária, Guarda Nacional Republicana (GNR), Lisbon, Portugal.
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.

