Contribuição da aplicação do ultrassom de baixa potência na prevenção de osteopenia em tíbias de ratos sob ausência de carga (The contribution of the application of low power ultrasound to the prevention of rat tibial osteopenia under the absence of load)

ABSTRACT This work intended to verify if the low power ultrasound (US) prevents the occurrence of osteopenia on the tibia of rats under the absence of load. 45 adult male Wistar Rattus novergicus albinus were used, separated in five equal groups: C – control free animals in cages for 21 days; S – animals suspended by the tail for 21 days; ST – animals suspended by the tail for 21 days and concurrently treated with US; S→C – animals suspended for 21 days and then free in cages for another 21 days; S→C T – animals suspended for 21 days and then free in cages for another 21 days and concurrently treated with US. The treatment was performed with US with 1.5 MHz, work cycle 1:4, 30 mW/cm 2 , on tibia, for 15 sessions of 20 minutes each, 5 sessions per week. While still alive, the animals underwent bone densitometry examination to verify the Bone Mineral Density (BMD) and the Bone Mineral Content (BMC). After the euthanasia of the animals, the tibias were disjointed, dissected and underwent destructive mechanical