Principal trabecular structural orientation predicted by quantitative ultrasound is strongly correlated with $$\upmu $$ μ FEA determined anisotropic apparent stiffness

Abstract

The microarchitecture and alignment of trabecular bone adapts to the particular mechanical milieu applied to it. Due to this anisotropic mechanical property, measurement orientation has to be taken into consideration when assessing trabecular bone quality and fracture risk prediction. Quantitative ultrasound (QUS) has demonstrated the ability in predicting the principal structural orientation (PSO) of trabecular bone. Although the QUS prediction for PSO is very close to that of μCT, certain angle differences still exist. It remains unknown whether this angle difference can induce significant differences in mechanical properties or not. The objective of this study is to evaluate the mechanical properties in different PSOs predicted using different methods, QUS and μCT, thus to investigate the ability of QUS as a means to predict the PSO of trabecular bone noninvasively. By validating the ability of QUS to predict the PSO of trabecular bone, it is beneficial for future QUS applications because QUS measurements in the PSO can provide information more correlated with the mechanical properties than with other orientations. In this study, seven trabecular bone balls from distal bovine femurs were used to generate finite element models based on the 3-dimensional μCT images. Uniaxial compressive loading was performed on the bone ball models in the finite element analysis (FEA) in 6 different orientations (three anatomical orientations, two PSOs predicted by QUS and the longest vector of mean intercept length (MIL) tensor calculated by μCT). The stiffness was calculated based on the reaction force of the bone balls under loading and the von Mises stress results showed that both the mechanical properties in the PSOs predicted by QUS is significantly higher than the anatomical orientations and comparatively close to the longest vector of MIL tensor. The stiffness in the PSOs predicted by QUS is also highly correlated with the stiffness in the MIL tensor orientation (ATTmax vs. MIL, R2=0.98, p<001; UVmax vs. MIL, R2=0.92, p<001). These results were validated by in vitro mechanical testing on the bone ball samples. This study demonstrates that the PSO of trabecular bone predicted by QUS has an equally strong apparent stiffness with the orientation predicted by μCT.

Enhanced correlation between quantitative ultrasound and structural and mechanical properties of bone using combined transmission-reflection measurement

“…The upper limit of the 95% agreement is 2.73, and the lower limit is 0.93. 2012; Lin et al, 2014), and these results agreed with the founding of other researchers (Njeh et al, 1997b;Han and Rho, 1998;Nicholson et al, 1998;Hans et al, 1999). These previous results were obtained from ideal spherical trabecular bone specimens or models of which sample thickness remained the same for all measuring orientations.…”

“…Further study utilized a finite a) Author to whom correspondence should be addressed. Electronic mail: yi-xian.qin@stonybrook.edu element modeling of spherical trabecular bone and validated the QUS prediction of PSO (Lin et al, 2014). The mechanical properties in the PSO predicted by QUS are significantly higher than the anatomical orientations and comparatively close to the longest vector of the MIL tensor.…”

“…The mechanical properties in the PSO predicted by QUS are significantly higher than the anatomical orientations and comparatively close to the longest vector of the MIL tensor. While traditional QUS measurement, especially of the human calcaneus, is performed in medial-lateral orientation, the results of our previous work indicate that QUS measurement can determine the structural alignment of trabecular bone and correlate strongly with mechanical properties of the trabecular bone (Lin et al, 2012;Lin et al, 2014). By performing ultrasound scan in the PSO, the prediction of mechanical properties can be improved from simply performing QUS measurement conventionally in the medial-lateral orientation.…”

Signal of Interest Selection Standard for Ultrasonic Backscatter in Cancellous Bone Evaluation

“…However, BMD alone explains only 60% of fracture predictions (Harrar et al 2013). Quantitative ultrasound (QUS) is an attractive, safe, inexpensive and portable alternative for bone assessment using non-ionizing radiation (Fujita et al 2013;Ha€ ıat et al 2005;Laugier and Ha€ ıat 2011;Le et al 2010;Lin et al 2014;Padilla et al 2006;Roggen et al 2015;Ta et al 2009;Xu et al 2014;Zhang et al 2014).…”

Spatial distribution and remodeling of elastic modulus of bone in micro-regime as prediction of early stage osteoporosis

“…Efforts are being put in other methods of diagnosis of clinical fracture risk. Some the alternative methods include use of ultrasound (Hakulinen et al, 2004; Kotha et al, 2008; Lin et al, 2014; Qin et al, 2013) and quantitative computed tomography (QCT) and peripheral QCT (pQCT) techniques (Engelke et al, 2013; Xing et al, 2003) to determine bone strength and micro-architecture.…”