Journal of the mechanical behavior of biomedical materials
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J Mech Behav Biomed Mater · May 2014
Development and validation of an advanced anisotropic visco-hyperelastic human brain FE model.
This paper proposes the implementation of fractional anisotropy and axonal fiber orientation from diffusion tensor imaging (DTI) of 12 healthy patients into an existing human FE head model to develop a more realistic brain model with advanced constitutive laws. Further, the brain behavior was validated in terms of brain strain against experimental data published by Hardy et al. (2001, 2007) and for brain pressure against Nahum et al. (1977) experimental impacts. A reasonable agreement was observed between the simulation and experimental data. Results showed the feasibility of integrating axonal direction information into FE analysis and established the context of computation of axonal elongation in case of head trauma.
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J Mech Behav Biomed Mater · May 2014
The validation and application of a finite element human head model for frontal skull fracture analysis.
Traumatic head injuries can result from vehicular accidents, sports, falls or assaults. The current advances in computational methods and the detailed finite element models of the human head provide a significant opportunity for biomechanical study of human head injuries. The biomechanical characteristics of the human head through head impact scenarios can be studied in detail by using the finite element models. ⋯ The model is used to simulate the experimental frontal head impact tests using a cylindrical padded impactor. Results of the computational simulation shows that the model correlated well with a number of experimental data and a global fracture pattern has been predicted well by the model. Therefore the presented numerical model could be used for reconstruction of head impacts in different impact conditions also the forensic application of the head model would provide a tool for investigation of the causes and mechanism of head injuries.
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J Mech Behav Biomed Mater · May 2014
The relation between mechanical impact parameters and most frequent bicycle related head injuries.
The most frequent head injuries resulting from bicycle accidents include skull fracture acute subdural hematoma (ASDH), cerebral contusions, and diffuse axonal injury (DAI). This review includes epidemiological studies, cadaver experiments, in vivo imaging, image processing techniques, and computer reconstructions of cycling accidents used to estimate the mechanical parameters leading to specific head injuries. The results of the head impact tests suggest the existence of an energy failure level for the skull fracture, specific for different impact regions (22-24J for the frontal site and 5-15J for temporal site). ⋯ Internal brain lesions are strongly related to rotational effects which are not appropriately accounted by the commonly accepted head injury criterion (HIC). The research summarized in this paper adds significantly to the creation of a fundamental knowledge for the improvement of bicycle helmets as well as other head protective measures. The described investigations and experimental results are of crucial importance also for forensic research.