Modeling the Biodynamical Response of the Human Head for Injury Analysis

Modeling the Biodynamical Response of the Human Head for Injury Analysis PDF Author: Danielle N. George
Publisher:
ISBN: 9781423525363
Category :
Languages : en
Pages : 106

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Book Description
The objective of this study is to develop a finite element model of the human head and neck to investigate the biomechanics of head injury. The finite element model is a two-dimensional, plane strain representation of the cervical spine, skull, and major components of the brain including the cerebrum, cerebellum, brain stem, tentorium and the surrounding cerebral spinal fluid. The dynamic response of the model is validated by comparison with the results of human volunteer sled acceleration experiments conducted by Ewing et al. 10 . To validate the head model, one of the head impact experiments performed on cadavers by Nahum et al. 24, is simulated. The model responses are compared with the measured cadaveric test data in terms of head acceleration, and intracranial pressures measured at four locations including the coup and contrecoup sites. The validated model is used to demonstrate that the Head Injury Criterion (HIC), which is based on resultant translational acceleration of the center of gravity of the head, does not relate to the various mechanisms of brain injury and is therefore insufficient in predicting brain injury.

Modeling the Biodynamical Response of the Human Head for Injury Analysis

Modeling the Biodynamical Response of the Human Head for Injury Analysis PDF Author: Danielle N. George
Publisher:
ISBN: 9781423525363
Category :
Languages : en
Pages : 106

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Book Description
The objective of this study is to develop a finite element model of the human head and neck to investigate the biomechanics of head injury. The finite element model is a two-dimensional, plane strain representation of the cervical spine, skull, and major components of the brain including the cerebrum, cerebellum, brain stem, tentorium and the surrounding cerebral spinal fluid. The dynamic response of the model is validated by comparison with the results of human volunteer sled acceleration experiments conducted by Ewing et al. 10 . To validate the head model, one of the head impact experiments performed on cadavers by Nahum et al. 24, is simulated. The model responses are compared with the measured cadaveric test data in terms of head acceleration, and intracranial pressures measured at four locations including the coup and contrecoup sites. The validated model is used to demonstrate that the Head Injury Criterion (HIC), which is based on resultant translational acceleration of the center of gravity of the head, does not relate to the various mechanisms of brain injury and is therefore insufficient in predicting brain injury.

On the Dynamic Pressure Response of the Brain During Blunt Head Injury

On the Dynamic Pressure Response of the Brain During Blunt Head Injury PDF Author: Christopher William Pearce
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description


Models and Analogues for the Evaluation of Human Biodynamic Response, Performance and Protection

Models and Analogues for the Evaluation of Human Biodynamic Response, Performance and Protection PDF Author: Henning E. von Gierke
Publisher:
ISBN:
Category : Aircraft accidents
Languages : en
Pages : 438

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Book Description


Using Finite Element Modeling to Analyze Injury Thresholds of Traumatic Brain Injury from

Using Finite Element Modeling to Analyze Injury Thresholds of Traumatic Brain Injury from PDF Author: Anna Marie Dulaney
Publisher:
ISBN:
Category :
Languages : en
Pages : 89

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Book Description
A finite element model was developed for a range of human head-sUAS impacts to provide multiple case scenarios of impact severity at two response regions of interest: global and local. The hypothesis was that for certain impact scenarios, local response injuries of the brain (frontal, parietal, occipital, temporal lobes, and cerebellum) have a higher severity level compared to global response injury, the response at the Center of Gravity (CG) of the head. This study is the first one to predict and quantify the influence of impact parameters such as impact velocity, location, offset, and angle of impact to severity of injury. The findings show that an sUAS has the potential of causing minimal harm under certain impact scenarios, while other scenarios cause fatal injuries. Additionally, results indicate that the human head’s global response as a less viable response region of interest when measuring injury severity for clinical diagnosis. It is hoped that the results from this research can be useful to assist decision making for treatments and may offer different perspectives in sUAS designs or operation environments.

Frontiers in Head and Neck Trauma

Frontiers in Head and Neck Trauma PDF Author: Narayan Yoganandan
Publisher: IOS Press
ISBN: 9789051993691
Category : Crash injuries
Languages : en
Pages : 770

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Book Description
Responding to the trend toward sustainable living, "Recipes and Tips for Sustainable Living" helps you make delicious food using natural ingredients. Inside this lushly illustrated volume, you'll find: Tips and techniques to grow and harvest natural, organic foods in and around your home. More than 80 mouth-watering recipes for cooking those ingredients. Tips on preservation and storage of your harvest. Health benefits of natural, organic ingredients. Chapters cover: Gardening - Heirloom gardening, container gardening, herbs and preserving. Beyond the Garden - Foraging, beekeeping, poultry and eggs. Wood and Water - Venison, wild turkey, duck, quail, small game, seafood and fish.

Traumatic Brain Injury

Traumatic Brain Injury PDF Author: Rajkumar Prabhu
Publisher:
ISBN:
Category : Biomechanics
Languages : en
Pages :

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Book Description
The brain is a complex organ and its response to the mechanical loads at all strain rates has been nonlinear and inelastic in nature. Split-Hopkinson Pressure Bar (SHPB) high strain rate compressive tests conducted on porcine brain samples showed a strain rate dependent inelastic mechanical behavior. Finite Element (FE) modeling of the SHPB setup in ABAQUS/Explicit, using a specific constitutive model (MSU TP Ver. 1.1) for the brain, showed non-uniform stress state during tissue deformation. Song et al.'s assertion of using annular samples for negating inertial effects was also tested. FE simulation results showed that the use of cylindrical or annular did not mitigate the initial hardening. Further uniaxial stress state was not maintained in either case. Experimental studies on hydration effects of the porcine brain on its mechanical response revealed two different phenomenological trends. The wet brain (~80% water wt./wt.) showed strain rate dependency along with two unique mechanical behavior patterns at quasi-static and high strain rates. The dry brain's (~0% water wt./wt.) response was akin to the response of metals. The dry brain's response also observed to be strain rate insensitivity in its Template 2009 elastic modulus and yield stress variations. Uncertainty analysis of the wet brain high strain rate data revealed large uncertainty bands for the sample-to-sample random variations. This large uncertainty in the brain material should be taken into in the FE modeling and design stages. FE simulations of blast loads to the human head showed that Pressure played a dominant role in causing blast-related Traumatic Brain Injury (bTBI). Further, the analysis of shock waves exposed the deleterious effect of the 3-Dimensional geometry of the skull in pinning the location of bTBI. The effects of peak negative Pressure at injury sites have been attributed to bTBI pathologies such as Diffuse Axonal Injury (DAI), subdural hemorrhage and cerebral contusion.

Finite Element Modeling of Human Brain Response to Football Helmet Impacts

Finite Element Modeling of Human Brain Response to Football Helmet Impacts PDF Author: Timothy Darling
Publisher:
ISBN:
Category : Brain
Languages : en
Pages : 63

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Book Description
The football helmet is a device used to help mitigate the occurrence of impact-related traumatic (TBI) and minor traumatic brain injuries (mTBI) in the game of American football. The current design methodology of using a hard shell with an energy absorbing liner may be adequate for minimizing TBI, however it has had less effect in minimizing mTBI. The latest research in brain injury mechanisms has established that the current design methodology has produced a helmet to reduce linear acceleration of the head. However, angular accelerations also have an adverse effect on the brain response, and must be investigated as a contributor of brain injury. To help better understand how the football helmet design features effect the brain response during impact, this research develops a validated football helmet model and couples it with a full LS-DYNA human body model developed by the Global Human Body Modeling Consortium (v4.1.1). The human body model is a conglomeration of several validated models of different sections of the body. Of particular interest for this research is the Wayne State University Head Injury Model for modeling the brain. These human body models were validated using a combination of cadaveric and animal studies. In this study, the football helmet was validated by laboratory testing using drop tests on the crown of the helmet. By coupling the two models into one finite element model, the brain response to impact loads caused by helmet design features can be investigated. In the present research, LS-DYNA is used to study a helmet crown impact with a rigid steel plate so as to obtain the strain-rate, strain, and stress experienced in the corpus callosum, midbrain, and brain stem as these anatomical regions are areas of concern with respect to mTBI.

Biomechanical Engineering Analyses of Head and Spine Impact Injury Risk Via Experimentation and Computational Simulation

Biomechanical Engineering Analyses of Head and Spine Impact Injury Risk Via Experimentation and Computational Simulation PDF Author: Adam Jesse Bartsch
Publisher:
ISBN:
Category :
Languages : en
Pages : 231

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Book Description
Head and spine injuries, such as traumatic brain injury, skull fracture, concussion and osteoligamentous cervical spine injury continue to be prevalent in motor vehicle crashes, athletics and the military. Automotive safety systems, athletic safety equipment and military personal protective paraphernalia designs have generally focused on protection discretely designed on a component basis head or spine but not a systems basis, considering the head-spine linkage simultaneously. But since the cervical spine acts as the attachment point for the head, the boundary conditions applied to the cervical spine influence the behavior of the head. Hence, in analyzing injury risk for the head and the spine, each structure composes one portion of an intrinsically linked osteoligamentous system; thus injury risk for the head and the cervical spine might be more appropriately considered concurrently as opposed to individually. Historically, component-based injury protection designs have utilized head and cervical spine injury risk criteria developed from human, animal and anthropomorphic surrogate studies. While a plethora of these prior studies separately analyzed head injury risk via linear acceleration, Head Injury Criterion (HIC) or Gadd Severity Index (GSI), or cervical spine injury risk via axial/shear forces, bending moments or the Neck Injury Criterion (Nij), relatively few of these studies employed a systems-based approach to understand coupled head-cervical spine injury risk behavior. Thus, designing for optimal head and cervical spine injury protection may not be as trivial as separate consideration of head or spine component injury thresholds. Therefore, through a series of six biomechanical engineering studies that comprised the chapters of this dissertation, the work presented here broadly investigated head and cervical spine injury protection on a systems-based approach considering head and cervical spine injury risk simultaneously. In Chapter 1, injury risk in inertial loading during real-world low energy minor rear car crashes was analyzed. In Chapter 2, these minor crashes from Chapter 1 were further investigated via use of numerical simulation in MADYMO. While Chapters 1 and 2 explored low energy car crash loading, Chapter 3 explored multivariate head and cervical spine injury implications from direct head loading during frontal airbag inflation in high energy experimental car crashes. Chapter 4 expanded the direct frontal head impact loading analyzed in Chapter 3 to include oblique and lateral impact loading during impact experiments with a Hybrid III anthropomorphic test device. The low- and high-energy injury analysis methods developed in Chapters 1 through 4 helped drive the study of multivariate injury risk in response to experimental omnidirectional athletic head impacts in Chapter 5. Chapter 6 further built on the high-energy athletic impacts from Chapter 5 via Matlab and Simulink simulation of helmeted impacts using a systems dynamics approach. Finally, Chapter 7 analyzed development of an impact pendulum, pilot cadaveric injury response to direct head impact and analysis of similar impacts in a helmeted human surrogate. The results of all of these related studies indicated that head and cervical spine injury risk were interrelated during direct or inertial car crash and athletic impacts.

Computational Models for the Human Body: Special Volume

Computational Models for the Human Body: Special Volume PDF Author: Nicholas, Philippe Ayache
Publisher: Gulf Professional Publishing
ISBN: 9780444515667
Category : Mathematics
Languages : en
Pages : 696

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Book Description
Provides a better understanding of the physiological and mechanical behaviour of the human body and the design of tools for their realistic numerical simulations, including concrete examples of such computational models. This book covers a large range of methods and an illustrative set of applications.

A 3D FEM COMPARATIVE STUDY ON THE IMPACT RESPONSE BETWEEN HUMAN HEAD AND NOCSAE HEAD DUE TO FREE FALL

A 3D FEM COMPARATIVE STUDY ON THE IMPACT RESPONSE BETWEEN HUMAN HEAD AND NOCSAE HEAD DUE TO FREE FALL PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
Abstract : We all enjoy sports be it watching or playing. Concussion is well known topic when it comes sports related injuries. However, concussion and brain injury is not exclusive to sports and outdoor activities. Sometimes, even the impact due to slip and fall at small heights can cause serious damage to the head and brain. This report studies the response generated in the human head model and the commercially use dummy NOCSAE headform due to drop from height of 2, 3, 4 and 5 feet. Earlier studies have related brain kinetics and head kinematics to concussion and traumatic brain injury (TBI). There are also studies that relate the linear and angular accelerations between different commercial dummy head models and the human head model, which were done experimentally. The main purpose of his study is to compare these parameters for the both models analytically using simulations. The linear velocity corresponding to each drop height were calculated and used as input data for the simulations. The impacts were simulated using RADIOSS solver in Hypermesh. Various parameters like contact force, linear acceleration and its components along each of the co-ordinate axes were extracted from the FE analysis. These values were utilized to calculate linear and angular acceleration for the entire models. These values were plotted against tolerance limits for various levels of brain injury. v It was observed that linear acceleration values for both the Human Head model and the dummy NOCSAE Headform confirm each other. Superior impact of the head was found most susceptible to traumatic brain injury followed by lateral impact when linear acceleration was considered as the criteria. The values of angular acceleration though did not represent glaring similarities between the two models, but there was a general trend of increase in angular acceleration with increase in drop height.