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

Published: American Journal of Veterinary Research, Volume 83: Issue 8*

Keyword: Dog; Osteoarthritis; Pain; Hip; Photobiomodulation; Laser Therapy

Author(s): João C. Alves, DVM, MSc, PhD; Ana Santos, DVM, MSc; Patrícia Jorge, DVM; L. Miguel Carreira, DVM, PhD 

Objective: To evaluate photobiomodulation (PBM) therapy in dogs with bilateral moderate to severe hip osteoarthritis

Methods:  Forty joints were assigned to a control group (CG, n=20) or treatment group (PBMT, n=20). CG received a 21-day course of meloxicam, and PBMT received treatment 14-20 J/cm² with a Class IV therapeutic laser over three weeks. Joint range of motion, thigh girth, the Canine Brief Pain Inventory (CBPI, divided into pain interference score - PIS and Pain Severity Score - PSS),  Hudson Visual Analogue Scale (HVAS), Liverpool Osteoarthritis in Dogs (LOAD), Canine  Orthopedic Index (COI, divided into function, gait, stiffness, and quality of life), and digital thermography evaluation of the hip joint 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 bodyweight of 65.7±12.1lb.  Osteoarthritis was classified as moderate (n=26) and severe (n=14). No differences were found at T0. Better results were observed in PBMT at +8d (p=0.01 for PSS, p=0.04 for function and  COI), +15d (p=0.01 for PSS and function, p=0.02 for PIS and function, p=0.03 for COI and p=0.04 for LOAD) and +30d (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 +15d- to 90d. Lower values were recorded in both thermographic views of joints in the PBMT during the treatment period. Kaplan-Meier estimators showed that PBMT produced longer periods with better results.

Conclusions:  PBMT reduced pain levels and improved clinical findings (including functional scores) in dogs with moderate to severe hip osteoarthritis. The mean number of days that joints in the PBMT group took to return to baseline values was significantly higher than in CG (meloxicam) and also showed improvements in joint ROM sometimes out to +90 days after discontinuing treatment.

Authors: João C. Alves^1,2, DVM, MSc, PhD; Ana Santos¹, DVM, MSc; Patrícia Jorge¹, DVM; L.  Miguel Carreira^3,4,5, DVM, PhD .

 1: Divisão de Medicina Veterinária, Guarda Nacional Republicana (GNR). Rua Presidente  Arriaga, 1200-771 Lisbon, Portugal. 

2: MED – Mediterranean Institute for Agriculture, Environment and Development, Instituto de Investigação e Formação Avançada, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554  Évora, Portugal;

3: Faculty of Veterinary Medicine, University of Lisbon (FMV/ULisboa) – Portugal; 

4: Interdisciplinary Centre for Research in Animal Health (CIISA) – University of Lisbon,  (FMV/ULisboa) – Portugal.

5: Anjos of Assis Veterinary Medicine Centre (CMVAA), Barreiro – Portugal