Determination of orthotropic bone elastic constants using FEA and modal analysis

W R Taylor, E Roland, H Ploeg, D Hertig, R Klabunde, M D Warner, M C Hobatho, L Rakotomanana, S E Clift

Research output: Contribution to journalArticle

171 Citations (Scopus)

Abstract

Finite element models have been widely employed in an effort to quantify the stress and strain distribution around implanted prostheses and to explore the influence of these distributions on their long-term stability. In order to provide meaningful predictions, such models must contain an appropriate reflection of mechanical properties. Detailed geometrical and density information is now readily available from CT scanning. However, despite the use of phantoms, a method of determining mechanical properties (or elastic constants) from bone density has yet to be made available in a usable form.In this study, a cadaveric bone was CT scanned and its natural frequencies were measured using modal analysis. Using the geometry obtained from the CT scan data, a finite element mesh was created with the distribution of density established by matching the mass of the FE bone model with the mass of the cadaveric bone. The maximum values of the orthotropic elastic constants were then established by matching the predictions from FE modal analyses to the experimental natural frequencies, giving a maximum error of 7.8% over 4 modes of vibration. Finally, the elastic constants of the bone derived from the analyses were compared with those measured using ultrasound techniques. This produced a difference of <1% for both the maximum density and axial Young's Modulus. This study has thereby produced an orthotropic finite element model of a human femur. More importantly, however, is the implication that it is possible to create a valid FE model by simply comparing the FE results with the measured resonant frequency of the CT scanned bone
Original languageEnglish
Pages (from-to)767-773
Number of pages7
Journal5th World Congress of Biomechanics Munich, Germany, 29 July - 4 August 2006
Volume35
Issue number6
Publication statusPublished - 2002

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Elastic constants
Modal analysis
Bone
Finite element method
Bone and Bones
Natural frequencies
Elastic Modulus
Mechanical properties
Vibration
Computerized tomography
Bone Density
Femur
Prostheses and Implants
Prosthetics
Elastic moduli
Ultrasonics
Scanning
Geometry

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Determination of orthotropic bone elastic constants using FEA and modal analysis. / Taylor, W R; Roland, E; Ploeg, H; Hertig, D; Klabunde, R; Warner, M D; Hobatho, M C; Rakotomanana, L; Clift, S E.

In: 5th World Congress of Biomechanics Munich, Germany, 29 July - 4 August 2006, Vol. 35, No. 6, 2002, p. 767-773.

Research output: Contribution to journalArticle

Taylor, WR, Roland, E, Ploeg, H, Hertig, D, Klabunde, R, Warner, MD, Hobatho, MC, Rakotomanana, L & Clift, SE 2002, 'Determination of orthotropic bone elastic constants using FEA and modal analysis', 5th World Congress of Biomechanics Munich, Germany, 29 July - 4 August 2006, vol. 35, no. 6, pp. 767-773.
Taylor, W R ; Roland, E ; Ploeg, H ; Hertig, D ; Klabunde, R ; Warner, M D ; Hobatho, M C ; Rakotomanana, L ; Clift, S E. / Determination of orthotropic bone elastic constants using FEA and modal analysis. In: 5th World Congress of Biomechanics Munich, Germany, 29 July - 4 August 2006. 2002 ; Vol. 35, No. 6. pp. 767-773.
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