Accuracy of finite element predictions in sideways load configurations for the proximal human femur

L. Grassi, E. Schileo, F. Taddei, L. Zani, M. Juszczyk, L. Cristofolini, M. Viceconti

Research output: Contribution to journalArticle

Abstract

Subject-specific finite element models have been used to predict stress-state and fracture risk in individual patients. While many studies analysed quasi-axial loading configurations, only few works simulated sideways load configurations, such as those arising in a fall. The majority among these latter directly predicted bone strength, without assessing elastic strain prediction accuracy. The aim of the present work was to evaluate if a subject-specific finite element modelling technique from CT data that accurately predicted strains in quasi-axial loading configurations is suitable to accurately predict strains also when applying low magnitude loads in sideways configurations. To this aim, a combined numerical-experimental study was performed to compare finite element predicted strains with strain-gauge measurements from three cadaver proximal femurs instrumented with sixteen strain rosettes and tested non-destructively under twelve loading configurations, spanning a wide cone (0-30° for both adduction and internal rotation angles) of sideways fall scenarios. The results of the present study evidenced a satisfactory agreement between experimentally measured and predicted strains (R 2 greater than 0.9, RMSE% lower than 10%) and displacements. The achieved strain prediction accuracy is comparable to those obtained in state of the art studies in quasi-axial loading configurations. Still, the presence of the highest strain prediction errors (around 30%) in the lateral neck aspect would deserve attention in future studies targeting bone failure.

Original languageEnglish
Pages (from-to)394-399
Number of pages6
JournalJournal of Biomechanics
Volume45
Issue number2
DOIs
Publication statusPublished - Jan 10 2012

Fingerprint

Weight-Bearing
Femur
Bone and Bones
Stress Fractures
Cadaver
Neck
Bone
Strain gages
Cones
Loads (forces)

Keywords

  • Experimental validation
  • Finite element
  • Human femur
  • Sideways fall

ASJC Scopus subject areas

  • Orthopedics and Sports Medicine
  • Rehabilitation
  • Biophysics
  • Biomedical Engineering

Cite this

Accuracy of finite element predictions in sideways load configurations for the proximal human femur. / Grassi, L.; Schileo, E.; Taddei, F.; Zani, L.; Juszczyk, M.; Cristofolini, L.; Viceconti, M.

In: Journal of Biomechanics, Vol. 45, No. 2, 10.01.2012, p. 394-399.

Research output: Contribution to journalArticle

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