Author Identifier (ORCID)
Abstract
Bone plates are widely used in orthopaedic surgery to stabilise fractured bones and support healing following traumatic injuries or osteotomies. However, conventional metallic bone plates suffer from stress shielding and stiffness mismatch with bone, which can hinder optimal healing. Additive manufacturing enables the incorporation of novel metamaterial architectures into polymer-based implants to enhance mechanical properties. The fatigue behaviour of these implants during the healing period is critical to ensuring their structural integrity and long-term performance. In this study, the compressive fatigue performance of fused deposition modelling (FDM)-printed carbon fibre-reinforced polylactic acid (CF-PLA) bone plates were investigated. Four metamaterial structures—tetrachiral, re-entrant, rotating square, and hexagonal—were evaluated under strain-controlled cyclic loading at 20%, 40%, 60%, and 80% of their respective yield strains. The results showed a strong dependence of fatigue behaviour on lattice geometry. Among the tested configurations, the re-entrant structured bone plate exhibited the best overall fatigue performance, sustaining up to 100,000 cycles at moderate strain levels and showing delayed stiffness degradation under high strain conditions. In contrast, rotating square and hexagonal structures showed early stiffness loss and failure at higher strain levels. These findings highlight the importance of lattice design in fatigue performance, although FDM-induced printing defects significantly influence overall fatigue behaviour.
Keywords
3D printing, bone plate, CF-PLA, CFRP, fatigue behaviour, FDM, metamaterials, polymers
Document Type
Journal Article
Date of Publication
5-1-2026
Article Number
1152
Volume
18
Issue
10
Publication Title
Polymers
Publisher
MDPI
School
Centre for Advanced Materials and Manufacturing / School of Engineering
RAS ID
95275
Funding Information
The first author would like to thank Edith Cowan University for the awarded (ECU-HDR) higher degree research scholarship.
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Recommended Citation
Daniel, A., Bakhtiari, H., Das, B. K., Aamir, M., & Tolouei-Rad, M. (2026). Comparative fatigue analysis of CF-PLA metamaterial bone plates for orthopaedic fixation. Polymers, 18(10). https://doi.org/10.3390/polym18101152