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The Effects of Skull Thickness Variations on Human Head Dynamic Impact Responses
Published November 01, 2001 by The Stapp Association in United States
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Event: STAPP Car Crash Conference
Variations in human skull thickness affecting human head dynamic impact responses were studied by finite element modeling techniques, experimental measurements, and histology examinations. The aims of the study were to better understand the influences of skull thickness variations on human head dynamic impact responses and the injury mechanisms of human head during direct impact.
The thicknesses of the frontal bone of seven human cadaver skulls were measured using ultrasonic technology. These measurements were compared with previous experimental data. Histology of the skull was recorded and examined. The measured data were analyzed and then served as a reference to vary the skull thickness of a previously published three-dimensional finite element human head model to create four models with different skull thickness. The skull thicknesses modeled are 4.6 mm, 5.98 mm, 7.68 mm, and 9.61 mm.
These models were impacted by a cylinder with a mass of 5.23 kg and an initial velocity of 6.33 m/s. Model responses were compared between models in terms of intracranial pressures, head impact accelerations, brain shear stresses, and skull von Mises stresses. It has been shown that the thickness of the skull influenced the dynamic responses of the head during direct impact. As skull thickness increased, skull deformation decreased as the skull absorbed less impact energy. However, this relationship cannot be linearly interpolated to the other parameters such as head acceleration and intracranial pressure responses. Based on model responses to half-sine wave pulses, skull and brain iso-stress curves were constructed for the thicker and thinner skulls. Thresholds for skull fracture and reversible concussion were established for the population represented by these skulls.
CitationRuan, J. and Prasad, P., "The Effects of Skull Thickness Variations on Human Head Dynamic Impact Responses," SAE Technical Paper 2001-22-0018, 2001, https://doi.org/10.4271/2001-22-0018.
- Got, G. Guillon, F. Patel, A. Mack, P. Brun-Cassan, F. Fayon, A. Tarriere, C. Hureau, J. 1983 Morphological and biomechanical study of 146 human skulls used in experimental impacts in relation with the observed injuries Proc. 27 th Stapp Car Crash Conference, SAE Paper No. 831619
- Gurdjan, E.S., et al 1966 Mechanisms of head injury Clin. Neurosurg 12 112 128
- Hertz, E. 1993 A note on the Head Injury Criterion (HIC) as a predictor of the risk of skull fracture 37 th Annual proceedings Association for the Advancement of Automotive Medicine November 4–6 San Antonio, Texas
- Hodgson, V.R. Brinn, J. Thomas, L.M. Greenberg, S.W. 1970 Fracture behavior of the skull frontal bone against cylindrical surface Proc. 14 th Stapp Car Crash Conference, SAE Paper No. 700909
- Kopecky, J.A. Ripperger, E.A. 1969 Close brain injury: an engineering analysis J. Biomechanics 2 29 34
- Mertz, H.J. Prasad, P. Nusholtz, G. 1996 Head injury risk assessment for forehead impacts SAE Paper No. 960099
- Ono, K. Kikuchi, A. Nakamura, M. Kobayashi, H. Nakamura, N. 1980 Human head tolerance to sagittal impact reliable estimation deduced from experimental head injury using subhuman primates and human cadaver skull Proc. 24 th Stapp Car Crash Conference, SAE Paper No. 801303
- Prasad, P. Mertz, H.J. 1985 The position of the United States delegation to the ISO Working Group 6 on the use of HIC in automotive environment SAE Paper No. 851246
- Ruan, J.S. Khalil, T.B. King, A.I. 1991 Human head dynamic response to side impact by finite element modeling ASME Journal of Biomechanical Engineering 113 276 283
- Ruan, J.S. Khalil, T.B. King, A.I. 1993 Finite element modeling of direct head impact Proc. 37th Stapp Car Crash Conf, SAE Paper No. 933114
- Ruan, J.S. Khalil, T.B. King, A.I. 1994 Dynamic response of the human head to impact by three-dimensional finite element analysis ASME Journal of Biomechanical Engineering 116 44 50
- Ruan, J. S. Prasad, P. 1994 Head injury potential assessment in frontal impact by mathematical modeling Proc. 38th Stapp Car Crash Conf, SAE Paper No. 942212
- Ruan, J. S. Prasad, P. 1995 Coupling of a finite element head model with a lumped parameter Hybrid III dummy model - preliminary results Journal of Neurotrauma 12 No. 4 725 734
- Ruan, J. S. Prasad, P. 1998 Biomechanical study of head injury through finite element analysis Frontiers in Head and Neck Trauma - Clinical and Biomechanical Yoganandan, N. Pintar, F. A. Larson, S. J. Sancers, A. ISO Press 1998 377 397