Which Activity Might Cause the Most Wear of Total Knee Prostheses During Daily Living? A Finite Element Analysis.

Abstract

The complications induced by wear debris were the main reasons for the long-term failure of total knee arthroplasty (TKA). Wear prediction based on level walking in the International Organization for Standardization (ISO) 14243 standard could not accurately reflect the activities of TKA patients, especially other activities of daily living (ADLs). This study aimed to investigate the biomechanical effects and evaluate the wear of the prostheses during different ADLs. There were seven finite element models used to predict the wear of prostheses within 5 million cycles during six ADLs presented in the ISO 14243 standard and American Society for Testing and Materials (ASTM) F3141 standard, including level walking in the ISO standard, straight walking (SWA), pivot turn (PTA), cross-over turn (CTA), stair ascent, stair descent, and sit-stand sit in the ASTM standard. Although there was not much difference in the results between ISO walking and ASTM walking, the stress and wear depth on the insert of the other ADLs increased significantly, and the wear distribution was more dispersed. The maximum wear depth of PTA and CTA was higher than that of SWA, while the mass wear rates of stair descent, stair ascent, and sit-stand sit were much higher than those of PTA, CTA, and SWA. The wear of prostheses during various ADLs was distinctly different, suggesting that more attention should be paid to the influence of ADLs on the wear evaluation and prosthesis design. Total knee arthroplasty patients need to choose daily activities cautiously to prolong the life of the prosthesis.