Mechanical alignment tolerance of a cruciate-retaining knee prosthesis under gait loading-A finite element analysis

Yichao Luan; Huizhi Wang; Chaohua Fang; Min Zhang; Junwei Li; Ningze Zhang; Bolun Liu; Jian Su; Cheng-Kung Cheng

doi:10.3389/fbioe.2023.1148914

Mechanical alignment tolerance of a cruciate-retaining knee prosthesis under gait loading-A finite element analysis

Front Bioeng Biotechnol. 2023 Mar 30:11:1148914. doi: 10.3389/fbioe.2023.1148914. eCollection 2023.

Authors

Yichao Luan¹, Huizhi Wang², Chaohua Fang^{2

3}, Min Zhang¹, Junwei Li¹, Ningze Zhang¹, Bolun Liu¹, Jian Su¹, Cheng-Kung Cheng²

Affiliations

¹ Key Laboratory of Biomechanics and Mechanobiology, Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, China.
² School of Biomedical Engineering, Shanghai Jiao Tong University, Engineering Research Center of Digital Medicine, Ministry of Education, Shanghai, China.
³ Department of Sport Medicine, Ningbo No 6 Hospital, Ningbo, China.

Abstract

Component alignment is one of the most crucial factors affecting total knee arthroplasty's clinical outcome and survival. This study aimed to investigate how coronal, sagittal, and transverse malalignment affects the mechanical behavior of the tibial insert and to determine a suitable alignment tolerance on the coronal, sagittal, and transverse planes. A finite element model of a cruciate-retaining knee prosthesis was assembled with different joint alignments (-10°, -7°, -5°, -3°, 0°, 3°, 5°, 7°, 10°) to assess the effect of malalignment under gait loading. The results showed that varus or valgus, extension, internal rotation, and excessive external rotation malalignments increased the maximum Von Mises stress and contact pressure on the tibial insert. The mechanical alignment tolerance of the studied prosthesis on the coronal, sagittal, and transverse planes was 3° varus to 3° valgus, 0°-10° flexion, and 0°-5° external rotation, respectively. This study suggests that each prosthesis should include a tolerance range for the joint alignment angle on the three planes, which may be used during surgical planning.

Keywords: alignment tolerance; contact pressure; finite element analysis; gait loading; knee prosthesis; stress.

Grants and funding

This research was funded by Ningbo Public Welfare Science and Technology project (grant number 2022S064), Yinzhou District Agriculture and Social Development Science and Technology Project (grant number 2022AS066), National Key Research and Development Program (grant number 2016YFC1101904) and Project of NINGBO Leading Medical & Health Discipline (grant number 2022-X13).