Acta Ortopédica Brasileira
Print version ISSN 1413-7852
MANDARANO-FILHO, Luiz Garcia; BEZUTI, Márcio Takey; MAZZER, Nilton and BARBIERI, Cláudio Henrique. Influence of cortical bone thickness on the ultrasound velocity. Acta ortop. bras. [online]. 2012, vol.20, n.3, pp. 184-190. ISSN 1413-7852. http://dx.doi.org/10.1590/S1413-78522012000300010.
OBJECTIVE: An experimental in vitro study was carried out to evaluate the influence of cortical bone thickness on ultrasound propagation velocity. METHODS: Sixty bone plates were used, made from bovine femurs, with thickness ranging from 1 to 6 mm (10 of each). The ultrasound velocity measurements were performed using a device specially designed for this purpose, in an underwater acoustic tank and with direct contact using contact gel. The transducers were positioned in two ways: on opposite sides, with the bone between them, for the transverse measurement; and parallel to each other, on the same side of the bone plates, for the axial measurements. RESULTS: In the axial transmission mode, the ultrasound velocity speed increased with cortical bone thickness, regardless of the distance between the transducers, up to a thickness of 5 mm, then remained constant thereafter. There were no changes in velocity when the transverse measures were made. CONCLUSION: Ultrasound velocity increased with cortical bone thickness in the axial transmission mode, until the thickness surpasses the wavelength, after which point it remained constant. Level of Evidence: Experimental Study.
Keywords : Ultrasonics; Acoustics; Bone and bones.