Experimental validation of a finite element model of a human cadaveric tibia

Hans A. Gray, Fulvia Taddei, Amy B. Zavatsky, Luca Cristofolini, Harinderjit S. Gill

Research output: Contribution to journalArticle

58 Citations (Scopus)

Abstract

Finite element (FE) models of long bones are widely used to analyze implant designs. Experimental validation has been used to examine the accuracy of FE models of cadaveric femurs; however, although convergence tests have been carried out, no FE models of an intact and implanted human cadaveric tibia have been validated using a range of experimental loading conditions. The aim of the current study was to create FE models of a human cadaveric tibia, both intact and implanted with a unicompartmental knee replacement, and to validate the models against results obtained from a comprehensive set of experiments. Seventeen strain rosettes were attached to a human cadaveric tibia. Surface strains and displacements were measured under 17 loading conditions, which consisted of axial, torsional, and bending loads. The tibia was tested both before and after implantation of the knee replacement. FE models were created based on computed tomography (CT) scans of the cadaveric tibia. The models consisted of ten-node tetrahedral elements and used 600 material properties derived from the CT scans. The experiments were simulated on the models and the results compared to experimental results. Experimental strain measurements were highly repeatable and the measured stiffnesses compared well to published results. For the intact tibia under axial loading, the regression line through a plot of strains predicted by the FE model versus experimentally measured strains had a slope of 1.15, an intercept of 5.5 microstrain, and an R 2 value of 0.98. For the implanted tibia, the comparable regression line had a slope of 1.25, an intercept of 12.3 microstrain, and an R2 value of 0.97. The root mean square errors were 6.0% and 8.8% for the intact and implanted models under axial loads, respectively. The model produced by the current study provides a tool for simulating mechanical test conditions on a human tibia. This has considerable value in reducing the costs of physical testing by preselecting the most appropriate test conditions or most favorable prosthetic designs for final mechanical testing. It can also be used to gain insight into the results of physical testing, by allowing the prediction of those variables difficult or impossible to measure directly.

Original languageEnglish
Article number031016-1
JournalJournal of Biomechanical Engineering
Volume130
Issue number3
DOIs
Publication statusPublished - Jun 2008

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Tibia
Knee prostheses
Tomography
Knee Replacement Arthroplasties
Weight-Bearing
Femur
Knee
Mechanical testing
Strain measurement
Axial loads
Testing
Prosthetics
Mean square error
Costs and Cost Analysis
Bone and Bones
Materials properties
Bone
Experiments
Stiffness

Keywords

  • Experimental validation
  • Finite element analysis
  • Human tibia bone
  • Oxford knee
  • Tibial metaphysis
  • Validated FE model of implanted tibia

ASJC Scopus subject areas

  • Biomedical Engineering
  • Biophysics

Cite this

Experimental validation of a finite element model of a human cadaveric tibia. / Gray, Hans A.; Taddei, Fulvia; Zavatsky, Amy B.; Cristofolini, Luca; Gill, Harinderjit S.

In: Journal of Biomechanical Engineering, Vol. 130, No. 3, 031016-1, 06.2008.

Research output: Contribution to journalArticle

Gray, Hans A. ; Taddei, Fulvia ; Zavatsky, Amy B. ; Cristofolini, Luca ; Gill, Harinderjit S. / Experimental validation of a finite element model of a human cadaveric tibia. In: Journal of Biomechanical Engineering. 2008 ; Vol. 130, No. 3.
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