title: Physically Realizable Three-Dimensional Bone Prosthesis Design With Interpolated Microstructures.
abstract: We present a new approach to designing three-dimensional, physically realizable porous femoral implants with spatially varying microstructures and effective material properties. We optimize over a simplified design domain to reduce shear stress at the bone-prosthetic interface with a constraint on the bone resorption measured using strain energy. This combination of objective and constraint aims to reduce implant failure and allows a detailed study of the implant designs obtained with a range of microstructure sets and parameters. The microstructure sets are either specified directly or constructed using shape interpolation between a finite number of microstructures optimized for multifunctional characteristics. We demonstrate that designs using varying microstructures outperform designs with a homogeneous microstructure for this femoral implant problem. Further, the choice of microstructure set has an impact on the objective values achieved and on the optimized implant designs. A proof-of-concept metal prototype fabricated via selective laser melting (SLM) demonstrates the manufacturability of designs obtained with our approach.
authors.affiliation: School of Mathematics and Physics, The University of Queensland, Brisbane QLD 4072, Australia e-mail: a.cramer@uq.edu.au.
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Cramer
authors.affiliation: School of Mathematics and Physics, The University of Queensland, Brisbane QLD 4072, Australia e-mail: vchallis@maths.uq.edu.au.
authors.forename: Vivien J
authors.initials: VJ
authors.lastname: Challis
authors.affiliation: School of Mathematics and Physics, The University of Queensland, Brisbane QLD 4072, Australia e-mail: apr@maths.uq.edu.au.
authors.forename: Anthony P
authors.initials: AP
authors.lastname: Roberts
mesh_terms: D001862:Bone Resorption / Q000209:etiology; D005269:Femur; D019736:Prostheses and Implants / Q000009:adverse effects; D011474:Prosthesis Design; D013314:Stress, Mechanical