Comparison of beam theory and finite-element analysis with in vivo bone strain data from the alligator cranium

Keith A. Metzger, W. J T Daniel, Callum F. Ross

Research output: Contribution to journalArticle

60 Citations (Scopus)

Abstract

The mechanical behavior of the vertebrate skull is often modeled using free-body analysis of simple geometric structures and, more recently, finite-element (FE) analysis. In this study, we compare experimentally collected in vivo bone strain orientations and magnitudes from the cranium of the American alligator with those extrapolated from a beam model and extracted from an FE model. The strain magnitudes predicted from beam and FE skull models bear little similarity to relative and absolute strain magnitudes recorded during in vivo biting experiments. However, quantitative differences between principal strain orientations extracted from the FE skull model and recorded during the in vivo experiments were smaller, and both generally matched expectations from the beam model. The differences in strain magnitude between the data sets may be attributable to the level of resolution of the models, the material properties used in the FE model, and the loading conditions (i.e., external forces and constraints). This study indicates that FE models and modeling of skulls as simple engineering structures may give a preliminary idea of how these structures are loaded, but whenever possible, modeling results should be verified with either in vitro or preferably in vivo testing, especially if precise knowledge of strain magnitudes is desired.

Original languageEnglish (US)
Pages (from-to)331-348
Number of pages18
JournalAnatomical Record - Part A Discoveries in Molecular, Cellular, and Evolutionary Biology
Volume283
Issue number2
DOIs
StatePublished - Apr 2005
Externally publishedYes

Fingerprint

Alligators and Crocodiles
Finite Element Analysis
alligators
finite element analysis
Skull
bones
Bone and Bones
skull
Vertebrates
strain differences
engineering
vertebrates

Keywords

  • Alligator
  • Bone strain
  • Feeding
  • Finite-element analysis
  • Skull biomechanics

ASJC Scopus subject areas

  • Agricultural and Biological Sciences (miscellaneous)
  • Anatomy

Cite this

Comparison of beam theory and finite-element analysis with in vivo bone strain data from the alligator cranium. / Metzger, Keith A.; Daniel, W. J T; Ross, Callum F.

In: Anatomical Record - Part A Discoveries in Molecular, Cellular, and Evolutionary Biology, Vol. 283, No. 2, 04.2005, p. 331-348.

Research output: Contribution to journalArticle

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