EFFECTS OF SONICATION ON ARTICULAR-CARTILAGE IN EXPERIMENTAL OSTEOARTHRITIS

Objective. TO Investigate the histological effect of therapeutic ultra sound on arthritic cartilage of rats with various severities of induce d osteoarthritis. Methods. Twenty-seven rats with 3 different stages ( Grade I, II, III) of papain induced knee arthritis received 7 min puls e sonication treatment, 3 times/week for 4 weeks. Another 77 rats with the same severity of induced arthritis were studied as controls. The severity of arthritis and related histopathological changes of articul ar cartilage were evaluated by bone scan and histological findings wit h hematoxylin and eosin stain. Results. ''Severity indexes'' based on bone scan decreased after sonication treatment in each study group, Hi stopathological findings indicated marked cartilage repair in the earl y stage of induced arthritis (Grade I). However, progressive cartilage damage present in untreated Grade II, III induced arthritis was signi ficantly reduced after sonication. Conclusion, Therapeutic ultrasound enhances cartilage repair in the early stage, and has the effect of ar resting further deteriorative damage in the later stage of induced art hritis.