Development, validation and application of a parametric pediatric head finite element model for impact simulations

Li, Zhigang<sup>1,2</sup>; Hu, Jingwen<sup>2</sup>; Zhang, Jinhuan<sup>1</sup>

Affiliations

¹Key Laboratory of Automotive Safety and Energy, Tsinghua University, Beijing, China

²University of Michigan Transportation Research Institute, Ann Arbor, Michigan, USA

Abstract

In this study, a statistical cranium geometry model for 0-3 month old children was developed based on CT images using a combination of principal component analysis (PCA) and multivariate regression analysis. Radial basis function (RBF) was used to morph a baseline child head FE model into three pediatric head geometries, representing a newborn, a 1.5-month-old, and a 3-month-old infant head. These three models were used in a parametric study in nearvertex drop conditions to quantify the sensitivity of different material parameters. Finally, model validation was conducted against peak head accelerations in cadaver tests under different drop conditions, and optimization technique was used to determine the material properties. Results showed that the statistical cranium geometry model based on CT images included realistic cranium size and shape, suture size, and skull/suture thickness, for 0-3 month-old children. The three pediatric head models generated by morphing had a comparable mesh quality with the baseline model. The elastic modulus of skull had the dominant effect on most head impact response measurements. Head geometry was a significant factor affecting the maximal principal stress of the skull (P=0.002) and maximal principal strain of the suture (P=0.021) after controlling the skull material. In average the 3-month-old head predicted higher peak head acceleration (6.45% higher), maximal principal stress (64.75% higher) and strain (66.31% higher) of the suture, but lower maximal principal stress (25.71% lower) and strain (11.54% lower) of the skull than those from the newborn head. Material properties of the brain had little effects on head acceleration and strain/stress within the skull and suture. Elastic moduli of the skull, suture, dura, and scalp were well determined through optimization technique to match the cadaver test. The method developed in this study made it possible to investigate the age effects on geometry changes on pediatric head impact responses. The parametric study demonstrated that it is important to consider the material properties and geometric variations together when estimating pediatric head responses and predicting head injury risks.

Cited Works (16)

Year	Entry
2008	Danelson KA, Geer CP, Stitzel JD, Slice DE, Takhounts EG. Age and gender based biomechanical shape and size analysis of the pediatric brain. Stapp Car Crash J. 2008;52:59-81. SAE 2008-22-0003.
1990	Kraus JF, Rock A, Hemyari P. Brain injuries among infants, children, adolescents, and young adults. Am J Dis Child. June 1990;144(6):684-691.
2007	Coats B, Margulies SS, Ji S. Parametric study of head impact in the infant. Stapp Car Crash J. 2007;51:1-15. SAE 2007-22-0001.
2006	Coats B, Margulies SS. Material properties of human infant skull and suture at high rates. J Neurotrauma. August 2006;23(8):1222-1232.
2010	Roth S, Raul J-S, Willinger R. Finite element modelling of paediatric head impact: global validation against experimental data. Comput Methods Prog Biomed. July 2010;99(1):25-33.
2009	Reed MP, Sochor MM, Rupp JD, Klinich KD, Manary MA. Anthropometric specification of child crash dummy pelves through statistical analysis of skeletal geometry. J Biomech. May 29, 2009;42(8):1143-1145.
2002	Klinich KD, Hulbert GM, Schneider LW. Estimating infant head injury criteria and impact response using crash reconstruction and finite element modeling. Stapp Car Crash J. 2002;46:165-194. SAE 2002-22-0009.
2007	Franklyn M, Peiris S, Huber C, Yang KH. Pediatric material properties: a review of human child and animal surrogates. Crit Rev Biomed Eng. 2007;35(3-4):197-342.
2004	Langlois JA, Rutland-Brown W, Thomas KE. Traumatic Brain Injury in the United States: Emergency Department Visits, Hospitalizations, and Deaths. Atlanta, GA: National Center for Injury Prevention and Contro, Centers for Disease Control and Prevention; October 2004.
1998	Thibault KL, Margulies SS. Age-dependent material properties of the porcine cerebrum: effect on pediatric inertial head injury criteria. J Biomech. December 1998;31(12):1119-1126.
2008	Roth S, Raul J-S, Willinger R. Biofidelic child head FE model to simulate real world trauma. Comput Methods Prog Biomed. June 2008;90(3):262-274.
1995	Willinger R, Taleb L, Kopp C-M. Modal and temporal analysis of head mathematical models. J Neurotrauma. August 1995;12(4):743-754.
2004	Prange MT, Luck JF, Dibb A, Van Ee CA, Nightingale RW, Myers BS. Mechanical properties and anthropometry of the human infant head. Stapp Car Crash J. 2004;48:279-299. SAE 2004-22-0013.
2001	Lapeer RJ, Prager RW. Fetal head moulding: finite element analysis of a fetal skull subjected to uterine pressures during the first stage of labour. J Biomech. September 2001;34(9):1125-1133.
1977	Snyder RG, Schneider LW, Owings CL, Reynolds HM, Golomb DH, Schork MA. Anthropometry of Infants, Children and Youths to Age 18 for Product Safety Design: Final Report. Ann Arbor, MI: The University of Michigan, Highway Safety Research Institute; May 31, 1977. Report No. UM-HSRI-77-17.
2002	Prange MT, Margulies SS. Regional, directional, and age-dependent properties of the brain undergoing large deformation. J Biomech Eng. 2002;124(2):244-252.

Cited By (1)

Year	Entry
2019	Alshareef AA. Deformation of the Human Brain Under Rotational Loading [PhD thesis]. Charlottesville, VA: University of Virginia; May 2019.