Comparative study of the efficacy of the topical application of hydrocortisone, therapeutic ultrasound and phonophoresis on the tissue repair process in rat tendons

The purpose of this study was to compare the treatment efficacy of topical application of hydrocortisone, therapeutic ultrasound (US) and phonophoresis on the rat′s Achilles tendon (tendo calcaneus) repair process after tenotomy. The two treated groups with US were made in a pulsed mode. The irradiation of US was performed at a frequency of 1 MHz and an intensity of 0.5 W/cm2 (SATA), for 5 min each session. The tendons were analyzed using the polarized light microscopy. The results showed that the treated group with the topical application of hydrocortisone has not been delivered transdermally and that the molecule of collagen responds to the ultrasonic stimulation. The treatment with phonophoresis was the more efficient method. These findings allow us to conclude that the US stimulates the acceleration of tissue repair processes and induces the transdermal delivery of hydrocortisone in a therapeutic concentration on the tendon. E-mail: parizoto@power.ufscar.br