Healing effects and superoxide dismutase activity of diode/Ga-As lasers in a rabbit model of osteoarthritis.
OBJECTIVE
Osteoarthritis is a major cause of pain and disability in joints. The present study investigated the effects of differences of wavelengths and continuous versus pulsed delivery modes of low-level laser therapy (LLT) in a rabbit model of osteoarthritis. Comparison of the healing effects and superoxide dismutase (SOD) activity between therapy using diode and Ga-As lasers was our primary interest.


METHODS
Simple continuous wave (808-nm diode) and super-pulsed wave (904-nm Ga-As) lasers were used. Osteoarthritis was induced by injecting hydrogen peroxide into the articular spaces of the right stifle in rabbits. The rabbits were randomly assigned to four groups: normal control without osteoarthritis induction (G1), osteoarthritis-induction group without treatment (G2), osteoarthritis induction with diode irradiation (G3), and osteoarthritis induction with Ga-As irradiation (G4). Laser irradiation was applied transcutaneously for 5 min every day for over four weeks, starting the first day after confirmation of induction of osteoarthritis. The induction of osteoarthritis and effects of LLT were evaluated by biochemistry, computed tomography, and histological analyses.


RESULTS
The SOD activity in G3 and G4 rabbits at two and four weeks after laser irradiation was significantly higher than that of G1 animals (p<0.05). However, there was no significant difference between G3 and G4 animals. Moreover, there were significant differences at two and four weeks between the control and osteoarthritis-induction groups, but no significant difference between G3 and G4 in the computed tomographic analyses and histological findings.


CONCLUSIONS
These results indicate that diode and Ga-As lasers are similarly effective in healing and inducing SOD activity for LLT applications in a rabbit model of OA.
Veterinary Medical Center, Chungbuk National University, Cheongju, Republic of Korea.
Jae Yeon
JY
Lee
Veterinary Medical Center, Chungbuk National University, Cheongju, Republic of Korea.
Sang Ui
SU
Lee
Veterinary Medical Center, Chungbuk National University, Cheongju, Republic of Korea.
Taekjoo
T
Lim
Veterinary Medical Center, Chungbuk National University, Cheongju, Republic of Korea shchoi@cbu.ac.kr.
Seok Hwa
SH
Choi
D000818:Animals; D004195:Disease Models, Animal; D004789:Enzyme Activation / Q000528:radiation effects; D053685:Laser Therapy; D007834:Lasers; D008297:Male; D010003:Osteoarthritis / Q000175:diagnosis / Q000201:enzymology* / Q000628:therapy*; D011817:Rabbits; D013264:Stifle / Q000378:metabolism / Q000473:pathology; D013482:Superoxide Dismutase / Q000378:metabolism*; D014057:Tomography, X-Ray Computed; D014945:Wound Healing / Q000528:radiation effects*
D013482:Superoxide Dismutase
Ga-As; diode; laser; osteoarthritis; superoxide dismutase