Low intensity pulsed ultrasound treatment increases rabbit radial fracture healing

ABSTRACT

In order to study the effect of ultrasound [US] on bone healing, a complete transverse fracture was made in the right radius of adult male rabbits by a cutter. 52 rabbits were used group 1, control [n=17]; group 2, test [n=15]; group 3, intact [n=1] and group 4 [n=12] who were examined only for evaluation of the cutter effects in detail. 7 animals were operated with a Gigli saw. The test group received US treatment 0.5 W/cm [2], 1MHz, 2 msec on-8 msec off for 10 min/day, from the day after surgery until complete fusion was observed. Radiological studies indicated that mean healing duration and rate of healing was significantly more in the test group than in controls. Histological evaluation showed the presence of ossified callus at week 3 in the test group, but in controls fibrous callus was still seen at week 5 after surgery. Bone mineral analyses by stereoelectron microscope showed that the mineral component of the treated bone reverts to normal, similar to the composition of intact bone, and sooner than that of the control. However, our results revealed no deleterious effects of US on treated and untreated ipsilateral and contralateral bones during the experiment or one month after complete fusion of the bones, at which time US was terminated