The effect of morphometric and geometric indices of the human calvarium on mechanical response

Kevin Adanty; Kapil B Bhagavathula; Karyne N Rabey; Michael R Doschak; Samer Adeeb; James D Hogan; Simon Ouellet; Thomas A Plaisted; Sikhanda S Satapathy; Dan L Romanyk; Christopher R Dennison

doi:10.1016/j.clinbiomech.2023.106012

The effect of morphometric and geometric indices of the human calvarium on mechanical response

Clin Biomech (Bristol, Avon). 2023 Jul:107:106012. doi: 10.1016/j.clinbiomech.2023.106012. Epub 2023 May 30.

Authors

Affiliations

¹ University of Alberta, Department of Mechanical Engineering, Edmonton, Canada. Electronic address: adanty@ualberta.ca.
² University of Alberta, Department of Mechanical Engineering, Edmonton, Canada.
³ University of Alberta, Department of Surgery 2D, Walter C Mackenzie Health Sciences Centre 8440 - 112 Street University of Alberta Edmonton, Alberta T6G 2B7, Canada; University of Alberta, Department of Anthropology, 13-15 Tory Building, University of Alberta, Edmonton, Alberta T6G 2H4, Canada.
⁴ University of Alberta, Faculty of Pharmacy and Pharmaceutical Sciences, 2-35 Medical Sciences Building 8613 - 114 Street, University of Alberta, Edmonton, Alberta T6G 2H7, Canada.
⁵ University of Alberta, Department of Civil and Environmental Engineering, 7-203 Danadeo Innovation Centre for Engineering 9211-116 Street NW University of Alberta, Edmonton, Alberta T6G 1H9, Canada.
⁶ Defence Research and Development Canada, Quebec City, Canada.
⁷ US Army Combat Capabilities Development Command - Army Research Laboratory, MD, USA.
⁸ University of Alberta, Department of Mechanical Engineering, Edmonton, Canada; University of Alberta, School of Dentistry, Katz Group Centre for Pharmacy and Health Research 87 Avenue - 114 Street, 7-020H Edmonton, Alberta T6G 2E1, Canada.
⁹ University of Alberta, Department of Mechanical Engineering, Edmonton, Canada; University of Victoria, Department of Mechanical Engineering, Victoria, Canada.

PMID: 37295339
DOI: 10.1016/j.clinbiomech.2023.106012

Abstract

Background: When developing a surrogate model of the human skull, there is a multitude of morphometric and geometric properties to consider when constructing the model. To simplify this approach, it is important to identify only the properties that have a significant influence on the mechanical response of the skull. The objective of this study was to identify which morphometric and geometric properties of the calvarium were significant predictors of mechanical response.

Methods: Calvarium specimens (N = 24) were micro-computed tomography scanned to determine morphometric and geometric properties. The specimens were assumed to be Euler-Bernoulli beams and were subject to 4-point quasi-static bending to determine mechanical response. Univariate linear regressions were performed whereby the morphometric and geometric properties were independent or predictor variables and the mechanical responses were dependent or outcome variables.

Findings: Nine significant linear regression models were established (p < 0.05). In the diploë, trabecular bone pattern factor was a significant predictor of force and bending moment at fracture. The inner cortical table had more significant predictors (thickness, tissue mineral density, and porosity) of mechanical response compared to the outer cortical table and diploë.

Interpretation: Morphometric and geometric properties had a key influence on the calvarium's biomechanics. Trabecular bone pattern factor and the morphometry and geometry of the cortical tables must be considered when evaluating the mechanical response of the calvarium. These properties can aid the design of surrogate models of the skull that seek to mimic its mechanical response for head impact simulation.

Keywords: Calvaria; Geometry; Mechanical response; Morphometry; Regressions.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Biomechanical Phenomena
Bone Density
Cancellous Bone*
Head
Humans
Skull* / diagnostic imaging
X-Ray Microtomography