Perguntas Essencias em Traumato Ortopedia PET
Palma IM, Abdalla RJ, Luciano RC, Fuchs R. Joelho. Perguntas Essencias em Traumato Ortopedia PET, São Paulo, v. ANO II, p. 19-34, 2006.
Pulsated ultrasonic therapy results upon the process of reparatuion of the calcaneal tendon in rats.
JOSPT, 2006. Abdalla RJ. Pulsated ultrasonic therapy results upon the process of reparatuion of the calcaneal tendon in rats. [no prelo]. JOSPT, 2006.
Study Design: Controlled Laboratory Study.
Level of Evidence: 1
Objective: The objective of this study was to evaluate the effect of therapeutic ultrasound on the calcaneal tendon repair process using extremely low irradiation power.
Background: Therapeutic ultrasound promotes formation and maturation of scar tissue.
Methods: Twenty-eight Wistar rats underwent surgical procedures (tenotomy and tenorrhaphy) in the calcaneal tendons of their right pelvic limbs. After the surgery the animals were randomly divided into two groups. The animals in Group 1 received daily applications of a 1-MHz frequency ultrasound device using a 0.15 W/cm2 SATA power in a 16-Hz frequency pulse mode (duty cycle 20%). The animals in Group 2 were subjected to the same treatment protocol, except that the apparatus was turned off during the application. After a 28-day treatment the animals were killed and their tendons were surgically removed and subjected to mechanical stress testing. The parameters analyzed were: cross-sectional area (mm2), breaking strength (Newton), tensile stress (Mpa) and energy absorption (mJ). The results of the intergroup analyses showed a statistically significant increase in the breaking strength (p=0.0063) and tensile stress values (p=0.0204) of (Treatment) Group 1 compared to (Control) Group 2. The intergroup analysis did not show statistically significant differences between the cross-sectional area values (in mm2).
Conclusion: The study supported the hypothesis that ultrasound applied in pulsated increases strength and tension of the tendon tissue.
Key Terms: therapeutic ultrasound; biomechanical testing; controlled laboratory study with rats.