Association between nanoscale strains and tissue level nanoindentation properties in age-related hip-fractures

Bonicelli, Andrea; Tay, Tabitha; Cobb, Justin P.; Boughton, Oliver R.; Hansen, Ulrich; Abel, Richard L.; Zioupos, Peter

Abstract

Measurement of the properties of bone as a material can happen in various length scales in its hierarchical and composite structure. The aim of this study was to test the tissue level properties of clinically-relevant human bone samples which were collected from donors belonging to three groups: ageing donors who suffered no fractures (Control); untreated fracture patients (Fx-Untreated) and patient who experienced hip fracture despite being treated with bisphosphonates (Fx-BisTreated). Tissue level properties were assessed by (a) nanoindentation and (b) synchrotron tensile tests (STT) where strains were measured at the ‘tissue’, ‘fibril’ and ‘mineral’ levels by using simultaneous Wide-angle - (WAXD) and Small angle- X-ray diffraction (SAXD). The composition was analysed by thermogravimetric analysis and material level endo- and exo-thermic reactions by differential scanning calorimetry (TGA/DSC3+). Irrespective of treatment fracture donors exhibited significantly lower tissue, fibril and mineral strain at the micro and nanoscale respectively and had a higher mineral content than controls. In nanoindentation only nanohardness was significantly greater for Controls and Fx-BisTreated versus Fx-Untreated. The other nanoindentation parameters did not vary significantly across the three groups. There was a highly significant positive correlation (p < 0.001) between organic content and tissue level strain behaviour. Overall hip-fractures were associated with lower STT nanostrains and it was behaviour measured by STT which proved to be a more effective approach for predicting fracture risk because evidently it was able to demonstrate the mechanical deficit for the bone tissue of the donors who had experienced fractures.

Citation

Bonicelli, A., Tay, T., Cobb, J. P., Boughton, O. R., Hansen, U., Abel, R. L., & Zioupos, P. (2023). Association between nanoscale strains and tissue level nanoindentation properties in age-related hip-fractures. Journal of the mechanical behavior of biomedical materials, 138, Article 105573. https://doi.org/10.1016/j.jmbbm.2022.105573

• Journal Article Type: Article
• Acceptance Date: Nov 15, 2022
• Online Publication Date: Nov 23, 2023
• Publication Date: Feb 1, 2023
• Deposit Date: Jul 19, 2023
• Publicly Available Date: Jul 21, 2023
• Journal: Journal of the Mechanical Behavior of Biomedical Materials
• Print ISSN: 1751-6161
• Electronic ISSN: 1878-0180
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 138
• Article Number: 105573
• DOI: https://doi.org/10.1016/j.jmbbm.2022.105573
• Keywords: Bone properties; Synchrotron; Nanoindentation; Fracture; Ageing
• Public URL: https://hull-repository.worktribe.com/output/4287110