About the inevitable compromise between spatial resolution and accuracy of strain measurement for bone tissue: A 3D zero-strain study

JOURNAL OF BIOMECHANICS

卷:47

Article

Dall'Ara, E.^1,2  Barber, D.³  Viceconti, M.^1,2 

[1] Univ Sheffield, Dept Mech Engn, Sheffield, S Yorkshire, England

[2] Univ Sheffield, INSIGNEO, Inst Silico Med, Sheffield, S Yorkshire, England

[3] Univ Sheffield, Dept Cardiovasc Sci, Sheffield, S Yorkshire, England

关键词: Bone;    Strain;    DVC;    Registration;    MicroCT;   

DOI  :  10.1016/j.jbiomech.2014.07.019

来源: Elsevier

【 摘 要 】

The accurate measurement of local strain is necessary to study bone mechanics and to validate micro computed tomography (mu CT) based finite element (FE) models at the tissue scale. Digital volume correlation (DVC) has been used to provide a volumetric. estimation of local strain in trabecular bone sample with a reasonable accuracy. However, nothing has been reported so far for mu CT based analysis of cortical bone. The goal of this study was to evaluate accuracy and precision of a deformable registration method for prediction of local zero-strains in bovine cortical and trabecular bone samples. The accuracy and precision were analyzed by comparing scans virtually displaced, repeated scans without any repositioning of the sample in the scanner and repeated scans with repositioning of the samples. The analysis showed that both precision and accuracy errors decrease with increasing the size of the region analyzed, by following power laws. The main source of error was found to be the intrinsic noise of the images compared to the others investigated. The results, once extrapolated for larger regions of interest that are typically used in the literature, were in most cases better than the ones previously reported. For a nodal spacing equal to 50 voxels (498 mu m), the accuracy and precision ranges were 425-692 mu epsilon and 202-394 mu epsilon, respectively. In conclusion, it was shown that the proposed method can be used to study the local deformation of cortical and trabecular bone loaded beyond yield, if a sufficiently high nodal spacing is used. (C) 2014 Elsevier Ltd. All rights reserved.

【 授权许可】

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