Design of a lightweight universal talus implant using topology optimization

Frontiers in Bioengineering and Biotechnology

Bioengineering and Biotechnology

Ahmed H. Hafez¹  Andreas Schiffer¹  Marwan El-Rich²  Nadr Jomha³  Tao Liu⁴ 

[1] Department of Mechanical Engineering, Khalifa University, Abu Dhabi, United Arab Emirates;Department of Mechanical Engineering, Khalifa University, Abu Dhabi, United Arab Emirates;Healthcare Engineering Innovation Center (HEIC), Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates;Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada;Human Performance Lab, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada;

关键词: talus implant design;    bioinspired design;    total talus replacement;    finite element analysis;    topology optimization;    contact pressure;    cartilage;   

DOI  :  10.3389/fbioe.2023.1228809

 received in 2023-05-25, accepted in 2023-08-07,  发布年份 2023

来源: Frontiers

【 摘 要 】

Total talus replacement is a promising alternative treatment for talus fractures complicated by avascular necrosis and collapse. This surgical option replaces the human talus bone with a customized talus implant and can maintain ankle joint functionality compared to traditional treatment (e.g., ankle fusion). However, the customized implant is costly and time-consuming due to its customized nature. To circumvent these drawbacks, universal talus implants were proposed. While they showed clinically satisfactory results, existing talus implants are heavier than biological talus bones as they are solid inside. This can lead to unequal weight between the implant and biological talus bone, and therefore leading to other complications. The reduction of the implants’ weight without compromising its performance and congruency with surrounding bones is a potential solution. Therefore, this study aims to design a lightweight universal talus implant using topology optimization. This is done through establishing the loading and boundary conditions for three common foot postures: neutral, dorsi- and plantar-flexion. The optimized implant performance in terms of mass, contact characteristics with surrounding joint cartilage and stress distributions is studied using a 3D Finite Element (FE) model of the ankle joint. The mass of the optimized implant is reduced by approximately 66.6% and its maximum stresses do not exceed 70 MPa, resulting in a safety factor of 15.7. Moreover, the optimized and solid implants show similar contact characteristics. Both implants produced peak contact pressures that were approximately 19.0%–196% higher than those produced by the biological talus. While further mechanical testing under in-vivo loading conditions is required to determine clinical feasibility, preliminarily, the use of a lightweight universal implant is expected to provide the patient with a more natural feel, and a reduced waiting period until surgery.

【 授权许可】

Unknown   
Copyright © 2023 Hafez, El-Rich, Liu, Jomha and Schiffer.