The Ability of Bone Mineral Density and Microstructural Indices to Reflect Mechanical Properties of Trabecular Bone

PURPOSE: The goals of this experimental study were to (1) apply high-resolution imaging techniques (micro-CT imaging) in combination with new computer modeling techniques (FEA) to quantify 3D microstructural and biomechanical properties of trabecular bone in the intertrochanteric region (2) investigate contribution of bone mineral density (BMD) and microstructure of trabecular bone to predicting its mechanical property, i.e., elastic modulus, and (3) determine if the prediction of bone elastic constant can be improved when BMD is combined with any one structural index, or the structural indices are associated each other as independent variable. MATERIALS AND METHODS: Total 15 trabecular bone core specimens were obtained from the proximal femurs with patients undergoing to total hip arthroplasty. BMD of all bone cores was measured using PIXImus2 densitometer. A high-resolution microcomputed tomography (micro-CT) was used to scan each specimen to obtain histomorphology. Microstructural parameters such as bone volume fraction (BV/TV), trabecular number (Tb.Th), trabecular separation (Tb.Sp) were directly calculated from the 2-D and 3-D datasets, and then the hexahedron mesh models were created. Micro-finite element analysis was performed to derive indices of mechanical properties of trabecular bone. The multiple relationships among BMD, structural parameters and mechanical indices were assessed using linear regression analyses. A p value<0.05 was considered to be significant. RESULTS: Linear regression analysis showed that the BV/TV was the best predictor for Young’s modulus (R²=0.758, p<0.001), as well as BMD (R²=0.752, p<0.001). The structure model index (SMI), Tb.Sp and Tb.N could well explain the variance of Young’s modulus by 51%, 42% and 39%, respectively. If BMD is supplemented with any of the examined structural indices there is a clear improvement for predicting Young’s moduli. Likewise, the ability to explain variance of Young’s modulus is improved by combining the structural indices each other. CONCLUSION: A combination of microstructural parameters each other or with bone mineral measurements could provide the best prediction of mechanical property of cancellous bone. Therefore, as regards detection of osteoporosis and evaluation of the efficacy of drug treatments for osteoporosis, BMD measurement should be supplemented with assessment of bone microarchitecture in vivo.

Author dc:creator

• 최, 문권

Contributors dc:contributor

• 원, 예연
• 대학원 의학과
• 200324516

• Bone mineral density
• Microstructure
• Mechanical properties
• Finite element analysis

Language dc:language

en

Identifier

http://dcoll.ajou.ac.kr:9080/dcollection/jsp/common/DcLoOrgPer.jsp?sItemId=000000000585
000000000585

OAI identifier oai:identifier

oai:repository.ajou.ac.kr:201003/1444