Influence of cancellous bone microstructure on two ultrasonic wave propagations in bovine femur: An in vitro study

Abstract

The influence of cancellous bone microstructure on the ultrasonic wave propagation of fast and slow waves was experimentally investigated. Four spherical cancellous bone specimens extracted from two bovine femora were prepared for the estimation of acoustical and structural anisotropies of cancellous bone. In vitro measurements were performed using a PVDF transducer (excited by a single sinusoidal wave at 1 MHz) by rotating the spherical specimens. In addition, the mean intercept length (MIL) and bone volume fraction (BV/TV) were estimated by X-ray micro-computed tomography. Separation of the fast and slow waves was clearly observed in two specimens. The fast wave speed was strongly dependent on the wave propagation direction, with the maximum speed along the main trabecular direction. The fast wave speed increased with the MIL. The slow wave speed, however, was almost constant. The fast wave speeds were statistically higher, and their amplitudes were statistically lower in the case of wave separation than in that of wave overlap.

Estimation of fast and slow wave properties in cancellous bone using Prony's method and curve fitting

“…Theoretical investigations of Biot theory in the context of cancellous bone have been reported by Cowin (1999); Pakula and Kubik (2002); Lee et al (2003Lee et al ( , 2006; Hughes et al (2003); Hughes et al (2007); Fellah et al (2004); , Sebaa et al (2006); Sebaa et al (2008); Aygun et al (2009) ;Cardoso and Cowin (2011); Cowin and Cardoso (2011); and Buchanan et al (2012). Additional experimental confirmations of Biot theory and two-wave phenomena in cancellous bone have been reported by Mohamed et al (2003), Wear et al (2005), Pakula et al (2008); Nagatani et al (2008Nagatani et al ( , 2009); Cardoso et al (2008); Mizuno et al (2009) ;Mizuno et al (2010); and Yamamoto et al (2009). Numerical applications in cancellous bone have been reported by Hosokawa (2005Hosokawa ( , 2008 and Nagatani et al (2008Nagatani et al ( , 2009).…”

“…Fast wave velocity in bovine cancellous bone depends on structural anisotropy and is maximum when propagation is parallel to the predominant trabecular orientation (Mizuno et al, 2010). Theoretical analysis suggests that the relative amplitudes of fast and slow waves are sensitive to bone volume fraction, sample thickness, tortuosity, and viscous characteristic length (Fellah et al, 2004).…”

An experimental study on the ultrasonic wave propagation in cancellous bone: Waveform changes during propagation

“…Because the fast wave mainly propagates in the solid trabecular frame, the wave properties reflect the state of the cancellous structure of the bone. [14][15][16] In addition, Otani has reported a good relation between the slow wave amplitude and bone volume and introduced a new bone densitometry apparatus for clinical studies. The apparatus can give us data which have a high correlation with bone mineral density by peripheral quantitative computed tomography.…”

The relationship between ultrasonic backscatter and trabecular anisotropic microstructure in cancellous bone

“…In the through-transmission measurement, the two-wave phenomenon would be more obvious when ultrasound propagates along the MTA orientation, and only a single slow wave would be observed in the case that ultrasound propagates perpendicular to the MTA orientation. [25][26][27] While for the ultrasonic backscatter measurement, the ultrasonic waves usually propagate perpendicular to the MTA orientation in order to obtain large backscatter signals. The backscatter signals would be much smaller when the ultrasound waves propagate along the MTA orientation.…”