Nondestructive characterization of bone tissue scaffolds for clinical scenarios

Ali Entezari; Zhongpu Zhang; Andrian Sue; Guangyong Sun; Xintao Huo; Che-Cheng Chang; Shiwei Zhou; Michael V Swain; Qing Li

doi:10.1016/j.jmbbm.2018.08.034

Nondestructive characterization of bone tissue scaffolds for clinical scenarios

J Mech Behav Biomed Mater. 2019 Jan:89:150-161. doi: 10.1016/j.jmbbm.2018.08.034. Epub 2018 Aug 25.

Authors

Ali Entezari¹, Zhongpu Zhang², Andrian Sue³, Guangyong Sun⁴, Xintao Huo⁵, Che-Cheng Chang⁶, Shiwei Zhou⁷, Michael V Swain⁸, Qing Li⁹

Affiliations

¹ School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, J07, Darlington, NSW 2006, Australia. Electronic address: ali.entezari@sydney.edu.au.
² School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, J07, Darlington, NSW 2006, Australia. Electronic address: leo.zhang@sydney.edu.au.
³ School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, J07, Darlington, NSW 2006, Australia. Electronic address: andrian.sue@sydney.edu.au.
⁴ School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, J07, Darlington, NSW 2006, Australia. Electronic address: guangyong.sun@sydney.edu.au.
⁵ State Key Laboratory of Advanced Design and Manufacture for Vehicle Body, Hunan University, Changsha 410082, China. Electronic address: huoxintao@hnu.edu.au.
⁶ School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, J07, Darlington, NSW 2006, Australia. Electronic address: ccha8453@uni.sydney.edu.au.
⁷ Centre for Innovative Structures and Materials, School of Engineering, RMIT University, GPO Box 2476, Melbourne, VIC 3001, Australia. Electronic address: shiwei.zhou@rmit.edu.au.
⁸ School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, J07, Darlington, NSW 2006, Australia. Electronic address: michael.swain@sydney.edu.au.
⁹ School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, J07, Darlington, NSW 2006, Australia. Electronic address: qing.li@sydney.edu.au.

PMID: 30286374
DOI: 10.1016/j.jmbbm.2018.08.034

Abstract

Objectives: This study aimed to develop a simple and efficient numerical modeling approach for characterizing strain and total strain energy in bone scaffolds implanted in patient-specific anatomical sites.

Materials and methods: A simplified homogenization technique was developed to substitute a detailed scaffold model with the same size and equivalent orthotropic material properties. The effectiveness of the proposed modeling approach was compared with two other common homogenization methods based on periodic boundary conditions and the Hills-energy theorem. Moreover, experimental digital image correlation (DIC) measurements of full-field surface strain were conducted to validate the numerical results.

Results: The newly proposed simplified homogenization approach allowed for fairly accurate prediction of strain and total strain energy in tissue scaffolds implanted in a large femur mid-shaft bone defect subjected to a simulated in-vivo loading condition. The maximum discrepancy between the total strain energy obtained from the simplified homogenization approach and the one obtained from detailed porous scaffolds was 8.8%. Moreover, the proposed modeling technique could significantly reduce the computational cost (by about 300 times) required for simulating an in-vivo bone scaffolding scenario as the required degrees of freedom (DoF) was reduced from about 26 million for a detailed porous scaffold to only 90,000 for the homogenized solid counterpart in the analysis.

Conclusions: The simplified homogenization approach has been validated by correlation with the experimental DIC measurements. It is fairly efficient and comparable with some other common homogenization techniques in terms of accuracy. The proposed method is implicating to different clinical applications, such as the optimal selection of patient-specific fixation plates and screw system.

Keywords: Digital image correlation (DIC); Homogenization technique; Mechanobiology; Orthopedics; Orthotropic properties; Tissue scaffold.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Biomechanical Phenomena
Bone and Bones / cytology*
Femur / cytology
Finite Element Analysis*
Models, Biological
Porosity
Stress, Mechanical*
Tissue Scaffolds*