The effect of low-intensity therapeutic ultrasound in induced fracture of rat tibiae

OBJECTIVE To analyze the possible effects of low-intensity ultrasound on induced tibia fracture of rats in a dose commonly used in physical therapy treatments. METHODS Twenty male Wistar rats were divided into two groups with 10 animals each. In the ultrasound group (USG), the animals were submitted to bone fracture and treatment with therapeutic ultrasound (TUS). Ultrasonic parameters are: frequency of 1.0 MHz, intensity of 0.2 W/cm2, pulsed mode at 20%, applied in stationary form during 10 minutes on the fracture region, for five weeks. The control group (CG) was submitted to bone fracture but not treated with ultrasound. RESULTS The radiographies showed better consolidation in USG compared to CG. The statistical tests for alkaline phosphatase and serum calcium did not show significant difference between groups. CONCLUSION According to this study, TUS, applied with these parameters (not commonly used for bone therapy) accelerates bone healing, confirmed by radiography, yet the biochemical analysis was not conclusive. One reason for this inconsistency may have been some inadequacy of the biochemical protocol, currently under investigation. Level of Evidence II, Prospective comparative study.