OBJECTIVES: The objective of this study was to compare the in vitro ultrasonic velocity and attenuation in bone healing evaluation. METHODS: Seventeen sheep weighting 37 kg in average were used, being divided into two groups of five animals each and one group of seven animals, according to the postoperative follow-up time (30, 60 and 90 days, respectively). Osteotomies were performed on the right tibiae and the intact left tibiae of the 17 animals were used as control. The healing process was monitored with conventional conventional radiographs taken at two-week intervals. The animals were sacrificed at the end of the corresponding followup period and both right and left tibiae were removed for in vitro underwater and contact ultrasound evaluations. The transverse and longitudinal ultrasound propagation velocity (USPV) and the broadband ultrasound attenuation (BUA) were measured and correlated. RESULTS: USPV increased with the progression of the healing process, while BUA decreased, with significant differences between the experimental and control groups and between the experimental groups, for most of the comparisons. CONCLUSION: It was concluded that the method using ultrasound as employed in this investigation is feasible and reliable for evaluating cortical bone healing.
Sheep; Tibia; Fracture Healing; Bone callus; Ultrasonic
