Are subject-specific models necessary to predict patellar tendon fatigue life? A finite element modelling study
Date
2021-09-11
Journal Title
Journal ISSN
Volume Title
Publisher
Taylor & Francis
Abstract
Patellar tendinopathy is an overuse injury that occurs from repetitive loading of the patellar tendon in a scenario resembling that of mechanical fatigue. As such, fatigue-life estimates provide a quantifiable approach to assess tendinopathy risk and may be tabulated using nominal strain (NS) or finite element (FE) models with varied subject-specificity. We compared patellar tendon fatigue-life estimates from NS and FE models of twenty-nine athletes performing countermovement jumps with subject-specific versus generic geometry and material properties. Subject-specific patellar tendon material properties and geometry were obtained using a data collection protocol of dynamometry, ultrasound, and magnetic resonance imaging. Three FE models were created for each subject, with: subject-specific (hyperelastic) material properties and geometry, subject-specific material properties and generic geometry, and generic material properties and subject-specific geometry. Four NS models were created for each subject, with: subject-specific (linear elastic) material properties and moment arm, generic material properties and subject-specific moment arm, subject-specific material properties and generic moment arm, and generic material properties and moment arm. NS- and FE-modelled fatigue-life estimates with generic material properties were poorly correlated with their subject-specific counterparts (r2≤0.073), while all NS models overestimated fatigue life compared to the subject-specific FE model (r2≤0.223). Furthermore, FE models with generic tendon geometry were unable to accurately represent the heterogeneous strain distributions found in the subject-specific FE models or those with generic material properties. These findings illustrate the importance of incorporating subject-specific material properties and FE-modelled strain distributions into fatigue-life estimations.
Description
Keywords
Patellar tendinopathy, Overuse injury, Finite Element Modelling, Strain
Citation
Firminger, C. R., Haider, I. T., Bruce, O. L., Wannop, J. W., Stefanyshyn, D. J., & Edwards, W. B. (2021). Are subject-specific models necessary to predict patellar tendon fatigue life? A finite element modelling study. Computer Methods in Biomechanics and Biomedical Engineering, 25(7), 729–739. https://doi.org/10.1080/10255842.2021.1975683