The effects of therapeutic ultrasound in corticosteroid induced achilles' tendinosis in rats (experimental study)

SUMMARYTHE EFFECTS OF THERAPEUTIC ULTRASOUND IN CORTICOSTEROIDINDUCED ACHILLES? TENDINOSIS IN RATS(Experimental Study)Dr.Ayşe SağolDokuz Eylul University Medicine FacultyPhysical Medicine and Rehabilitation Departmentnciraltı-ZM RThe purpose of this study is to investigate the effects of therapeutic ultrasound onfunctional level and histopathologic changes and to determine the appropriate therapeuticultrasound (pulsed 0,5 W/cm², underwater, 1- 3 MHz, 10 sessions) frequency when applied onexperimentally corticosteroid induced Achilles? tendinosis in rats.After having the approval of experimental animal studies ethics comitee 27 Achilles?tendons of 27 male Wistar white rats with normal activity were involved in the study. The ratsweighted 250-300 gr. 0,1 ml bethamethasone sodium phosphate was injectedintratendinosisly to the right Achilles? tendon of each rat. Injections were repeated with threeday intervals during four weeks. Rat functional walking test was applied at the end of the fourweeks. Rats were randomised to three gruops. In Group 1 (control group) sham ultrasoundwas applied. Rats in Group 2 were given 0,5 W/cm², 3MHz and rats in Group 3 were given0,5 W/cm², 1 MHz underwater pulsed ultrasound 4 min/day, consecutive 5 days per week and10 sessions in total. Rat functional walking test was repeated at the end of the treatmentperiod. Vernier caliper having the sensitivity of one percent of a milimeter was used formeasurements of functional walking test. Achilles? Functional Index (AFI) was calculated foreach tendon. After excision of right Achilles? tendons for histopathological studies the ratswere sacrifised by high dose ether exposion.The AFI scores of corticosteroid injected right leg and control left leg were comparedbefore the treatment and statistically significant increase was found in the degenerated rightleg. The AFI scores for right and left leg in each group after the treatment were compared andsignificant improvement was observed in the previosly increased AFI scores of right leg ofGroup 1 and 2. In Group 3 no significant improvement was detected.A total histopathologic score was calculated from individual histopathologicparameters. No statistically significant difference was detected between the groups accordingto total score and individual parameters however Group 2 and 3 had a tendency forimprovement.In conclusion there is no statistically significant improvement in AFI andhistopathologic scores after 1 and 3 MHz therapeutic ultrasound application in corticosteroidinduced Achilles? tendinosis in rats.Keywords: Therapeutic ultrasound, rat, Achilles? tendinosis