Finite Element Analysis of the Bearing Component of Total Ankle Replacement Implants during the Stance Phase of the Gait Cycle

Author Info

S J. Hazelwood, California Polytechnic State University, San Luis ObispoFollow
Mohammad N. Noori, California Polytechnic State University - San Luis ObispoFollow
Naudereh B. Noori, University of California, Irvine
Timothy S. Jain, California Polytechnic State University, San Luis ObispoFollow
Amanda Anderson, University of California, IrvineFollow
Joseph Rencis, Embry-Riddle Aeronautical UniversityFollow

Author ORCID Identifier

https://orcid.org/0000-0003-0990-2839

Recommended Citation

Published in BioMedInformatics, Issue 4, Fall September 3, 2024, pages 1949-1978.

The definitive version is available at https://doi.org/https://doi.org/10.3390/.

Abstract

Total ankle arthroplasty (TAA) is a motion-preserving treatment for end-stage ankle arthritis. An effective tool for analyzing these implants’ mechanical performance and longevity in silico is finite element analysis (FEA). An FEA in ABAQUS was used to statically analyze the mechanical behavior of the ultra-high-molecular-weight polyethylene (UHMWPE) bearing component at varying dorsiflexion/plantarflexion ankle angles and axial loading conditions during the stance phase of the gait cycle for a single cycle. The von Mises stress and contact pressure were examined on the articulating surface of the bearing component in two newly installed fixed-bearing TAA implants (Wright Medical INBONE II and Exactech Vantage). Six different FEA models of variable ankle compressive load levels and ankle angle positions, for the varying subphases of the stance phase of the gait cycle, were created. The components in these models were constrained to be conducive to the bone–implant interface, where implant loosening occurs. Our results showed that the von Mises stress and contact pressure distributions increased as the compressive load increased. The highest stress was noted at dorsiflexion angles > 15◦, in areas where the UHMWPE liner was thinnest, at the edges of the talar and UHMWPE components, and during the terminal stance phase of the gait cycle. This static structural analysis highlighted these failure regions are susceptible to yielding and wear and indicated stress magnitudes that are in agreement (within 25%) with those in previous static structural TAA FEAs. The mechanical wear of the UHMWPE bearing component in TAA can lead to aseptic loosening and peri-implant cyst formation over time, requiring surgical revision. This study provides ankle replacement manufacturers and orthopedic surgeons with a better understanding of the stress response and contact pressure sustained by TAA implants, which is critical to optimizing implant longevity and improving patient care.

Disciplines

Biomedical Engineering and Bioengineering

Copyright

© 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

Number of Pages

29