EFFECTIVENESS OF LED PHOTOBIOMODULATION THERAPY ON TREATMENT WITH KNEE OSTEARTHRITIS: AN RAT STUDY.

OBJECTIVE: The present study aimed to evaluate the effectivenesses of photobiomodulation therapy (PBMT) by light-emitting diode (LED) on osteoarthritis (OA) treatment in the knees of rats. DESIGN: Twenty male Wistar rats were randomly assigned into two experimental groups: Animals subjected to induction of OA, without therapeutic intervention (OAC); animals subjected to induction of OA treated with LED PBMT (850 nm, 200 mW, 6 J) (OAL). RESULTS: The results of gait analysis showed no statistical difference between the groups. The histological findings showed that the OAL group presented abnormal chondrocyte orientation, yet with less irregularities along fibrillation and the joint tissue. Thus, it presented a lower degenerative process when evaluated by the OARSI. Likewise, in the immunohistochemical analysis, the OAL group showed higher collagen 2 and TGF-beta immunoexpression when compared to the OAC group. CONCLUSION: Given the above, it is possible to suggest that the PBMT by LED had positive effects on the expression of ECM proteins responsible for synthesis of articular tissue.