Accuracy and precision of digital volume correlation in quantifying displacements and strains in trabecular bone
Accuracy and precision of digital volume correlation in quantifying displacements and strains in trabecular bone
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DOI：
10.1016/j.jbiomech.2007.04.019
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发表时间：
2007-01-01
影响因子：
2.4
通讯作者：
Morgan, Elise F.
中科院分区：
文献类型：
--
作者：
Liu, Li;Morgan, Elise F.
应变测量是研究小梁骨结构与功能关系的重要工具。数字体积相关 (DVC) 是一种测量样本内部应变的测量技术，而不仅仅是表面上的应变。 DVC 依赖于跟踪微结构特征的运动，因此，该技术的准确性和精度可能取决于小梁结构。这项研究量化了六种类型的骨小梁的位移和应变测量误差，这些骨小梁的体积分数和小梁结构范围很广。比较了不同骨型以及三种 DVC 方法的准确性和精密度。使用牛股骨远端、牛胫骨近端、兔股骨远端、兔胫骨近端、兔椎骨和人类椎骨标本的微型计算机断层扫描图像分析模拟和真实位移场。在 DVC 方法和骨类型之间发现位移和应变的准确度和精密度存在高达三倍的差异。位移精度、应变精度和精确度与结构模型指数等小梁结构测量值相关。这些结果表明 DVC 技术的性能取决于小梁结构。在所有骨类型中，位移误差和应变误差分别为 1.86-3.39 μ m 和 345-794 μ epsilon。对于来自人类椎骨和牛股骨远端的样本，测量误差大约比屈服应变小 20 倍。在这些情况下，DVC 是一种可行的技术，用于测量整个骨小梁样本和整个骨小梁室的屈服前和屈服后应变。 (c) 2007 Elsevier Ltd. 保留所有权利。
Strain measurement is an essential tool in the study of trabecular bone structure-function relationships. Digital volume correlation (DVC) is a measurement technique that quantifies strains throughout the interior of a specimen, rather than simply those on the surface. DVC relies on tracking the movement of microstructural features, and as such, the accuracy and precision of this technique may depend on trabecular structure. This study quantified displacement and strain measurement errors in six types of trabecular bone that spanned a wide range of volume fraction and trabecular architecture. Accuracy and precision were compared across bone type and also across three DVC methods. Both simulated and real displacement fields were analyzed using micro-computed tomography images of specimens from the bovine distal femur, bovine proximal tibia, rabbit distal femur, rabbit proximal tibia, rabbit vertebra, and human vertebra. Differences as large as three-fold in accuracy and precision of the displacements and strains were found among DVC methods and among bone types. The displacement precision and the strain accuracy and precision were correlated with measures of trabecular structure such as structural model index. These results demonstrate that the performance of the DVC technique can depend on trabecular structure. Across all bone types, the displacement and strain errors ranged 1.86-3.39 mu m and 345-794 mu epsilon, respectively. For specimens from the human vertebra and bovine distal femur, the measurement errors were approximately 20 times smaller than the yield strain. In these cases, DVC is a viable technique for measuring pre- and post-yield strains throughout trabecular bone specimens and the trabecular compartment of whole bones. (c) 2007 Elsevier Ltd. All rights reserved.