Predicting trabecular bone architecture through structural modelling
File(s)
Author(s)
Radukic, Branimir
Type
Thesis or dissertation
Abstract
Bone is a complex composite material at both micro and macro-scale. At macro-scale we distinguish between the external shell of bones, the cortex and a series of rods and plates which occupy the internal volume, the trabecular bone. This thesis focuses on advancing computationally efficient structural modelling methodology for trabecular bone, to achieve close resemblance with micro-CT imaging studies while maintaining agreement in predicted stiffness and relative density with macroscale continuum studies. A number of structural forms were examined to improve the understanding of trabecular bone behaviour. Good agreement between previous continuum and structural models and all rigid jointed lattice simulations was found. However, a bending dominated low connectivity lattice, particularly a space filling Voronoi inspired lattice, was found to most closely resemble real bone. The adaptation process, which for the first time, introduces a non-prismatic representation of trabeculae, created efficient robust structures. It is hypothesised that bone development processes leads to irregular structures.
Following adaptation, these structures exhibit an even strain distribution in response to loading and a higher resistance to damage than high connectivity structures. Low connectivity Voronoi and high connectivity near neighbour femur models were created. Favourable comparisons with clinical observations and previous studies were made, demonstrating the viability of the structural adaptation approach to generate physiologic models of whole bones which closely represent trabeculae at micro-scale. Despite advancements, limitations remain, including challenges in predicting trabecular thickness and matching the reported abundance of minimum connectivity nodes. The developed methodology holds promise in the development of additively manufactured bone scaffolds and implants with a micro-architecture more closely resembling that of trabecular bone. It has the potential to elucidate the development of skeletal
conditions such as osteoporosis and osteoarthritis. Finally, this approach can optimise structural engineering designs, improving material efficiency and response to damage and unexpected loading.
Following adaptation, these structures exhibit an even strain distribution in response to loading and a higher resistance to damage than high connectivity structures. Low connectivity Voronoi and high connectivity near neighbour femur models were created. Favourable comparisons with clinical observations and previous studies were made, demonstrating the viability of the structural adaptation approach to generate physiologic models of whole bones which closely represent trabeculae at micro-scale. Despite advancements, limitations remain, including challenges in predicting trabecular thickness and matching the reported abundance of minimum connectivity nodes. The developed methodology holds promise in the development of additively manufactured bone scaffolds and implants with a micro-architecture more closely resembling that of trabecular bone. It has the potential to elucidate the development of skeletal
conditions such as osteoporosis and osteoarthritis. Finally, this approach can optimise structural engineering designs, improving material efficiency and response to damage and unexpected loading.
Version
Open Access
Date Issued
2024-02-23
Date Awarded
2024-08-01
Copyright Statement
Creative Commons Attribution NonCommercial NoDerivatives Licence
Advisor
Phillips, Andrew
Publisher Department
Civil and Environmental Engineering
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)