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Schiks LAH, Dankelman J, Loeve AJ. Inflicted head-injury by shaking-trauma in infants: the importance of spatiotemporal variations of the head's rotation center. Sci Rep 2023; 13:15226. [PMID: 37709812 PMCID: PMC10502057 DOI: 10.1038/s41598-023-42373-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 09/09/2023] [Indexed: 09/16/2023] Open
Abstract
Inflicted head injury by shaking trauma (IHI-ST) in infants is a type of abusive head trauma often simulated computationally to investigate causalities between violent shaking and injury. This is commonly done with the head's rotation center kept fixed over time. However, due to the flexibility of the infant's neck and the external shaking motion imposed by the perpetrator it is unlikely that the rotation center is static. Using a test-dummy, shaken by volunteers, we demonstrated experimentally that the location of the head's rotation center moves considerably over time. We further showed that implementation of a spatiotemporal-varying rotation center in an improved kinematic model resulted in strongly improved replication of shaking compared to existing methods. Hence, we stress that the validity of current infant shaking injury risk assessments and the injury thresholds on which these assessments are based, both often used in court cases, should be re-evaluated.
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Affiliation(s)
- L A H Schiks
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Delft, The Netherlands
| | - J Dankelman
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Delft, The Netherlands
| | - A J Loeve
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Delft, The Netherlands.
- Co van Ledden Hulsebosch Center for Forensic Science and Medicine, Amsterdam, The Netherlands.
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Thresholds for the assessment of inflicted head injury by shaking trauma in infants: a systematic review. Forensic Sci Int 2019; 306:110060. [PMID: 31785511 DOI: 10.1016/j.forsciint.2019.110060] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 11/11/2019] [Accepted: 11/13/2019] [Indexed: 12/14/2022]
Abstract
In order to investigate potential causal relations between the shaking of infants and injuries, biomechanical studies compare brain and skull dynamic behavior during shaking to injury thresholds. However, performing shaking tolerance research on infants, either in vivo or ex vivo, is extremely difficult, if not impossible. Therefore, infant injury thresholds are usually estimated by scaling or extrapolating adult or animal data obtained from crash tests or whiplash experiments. However, it is doubtful whether such data accurately matches the biomechanics of shaking in an infant. Hence some thresholds may be inappropriate to be used for the assessment of inflicted head injury by shaking trauma in infants. A systematic literature review was conducted to 1) provide an overview of existing thresholds for head- and neck injuries related to violent shaking, and 2) to identify and discuss which thresholds have been used or could be used for the assessment of inflicted head injury by shaking trauma in infants. Key findings: The majority of studies establishing or proposing injury thresholds were found to be based on loading cycle durations and loading cycle repetitions that did not resemble those occurring during shaking, or had experimental conditions that were insufficiently documented in order to evaluate the applicability of such thresholds. Injury thresholds that were applied in studies aimed at assessing whether an injury could occur under certain shaking conditions were all based on experiments that did not properly replicate the loading characteristics of shaking. Somewhat validated threshold scaling methods only exist for scaling concussive injury thresholds from adult primate to adult human. Scaling methods that have been used for scaling other injuries, or for scaling adult injury thresholds to infants were not validated. There is a clear and urgent need for new injury thresholds established by accurately replicating the loading characteristics of shaking.
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3
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Abstract
Claims that new science is changing accepted medical opinion about abusive head injury have been made frequently in the media, legal publications and in legal cases involving abusive head trauma (AHT). This review analyzes recently published scientific articles about AHT to determine whether this new information has led to significant changes in the understanding, evaluation and management of children with suspected AHT. Several specific topics are examined: serious or fatal injuries from short falls; specificity of subdural hematoma for severe trauma; biomechanical explanations for findings; the specificity of retinal hemorrhages; the possibility of cerebral sinus thrombosis presenting with signs similar to AHT; and whether vaccines can produce such findings. We conclude: a) that the overwhelming weight of recent data does not change the fundamental consensus b) that abusive head trauma is a significant source of morbidity and mortality in children c) that subdural hematomas and severe retinal hemorrhages are commonly the result of severe trauma d) that these injuries should prompt an evaluation for abuse when identified in young children without a history of such severe trauma and e) that short falls, cerebral sinus thrombosis and vaccinations are not plausible explanations for findings that raise concern for abusive head trauma.
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4
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van Zandwijk JP, Vester MEM, Bilo RA, van Rijn RR, Loeve AJ. Modeling of inflicted head injury by shaking trauma in children: what can we learn? : Part II: A systematic review of mathematical and physical models. Forensic Sci Med Pathol 2019; 15:423-436. [PMID: 30784025 PMCID: PMC6687692 DOI: 10.1007/s12024-019-00093-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/16/2019] [Indexed: 12/01/2022]
Abstract
Various types of complex biomechanical models have been published in the literature to better understand processes related to inflicted head injury by shaking trauma (IHI-ST) in infants. In this systematic review, a comprehensive overview of these models is provided. A systematic review was performed in MEDLINE and Scopus for articles using physical (e.g. dolls) and mathematical (e.g. computer simulations) biomechanical models for IHI-ST. After deduplication, the studies were independently screened by two researchers using PRISMA methodology and data extracted from the papers is represented in a “7-steps description”, addressing the different processes occurring during IHI-ST. Eleven papers on physical models and 23 papers on mathematical models were included after the selection process. In both categories, some models focus on describing gross head kinematics during IHI-ST events, while others address the behavior of internal head- and eye structures in various levels of detail. In virtually all physical and mathematical models analyzed, injury thresholds are derived from scaled non-infant data. Studies focusing on head kinematics often use injury thresholds derived from impact studies. It remains unclear to what extent these thresholds reflect the failure thresholds of infant biological material. Future research should therefore focus on investigating failure thresholds of infant biological material as well as on possible alternative injury mechanism and alternative injury criteria for IHI-ST.
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Affiliation(s)
- Jan Peter van Zandwijk
- Division of Digital and Biometric Traces, Netherlands Forensic Institute, Laan van Ypenburg 6, 2497, GB, The Hague, the Netherlands
| | - Marloes E M Vester
- Department of Radiology and Nuclear Medicine, Academic Medical Center Amsterdam, Meibergdreef 9, 1105AZ, Amsterdam, the Netherlands.,Specialist Services and Expertise Division, Netherlands Forensic Institute, Laan van Ypenburg 6, 2497, GB, The Hague, the Netherlands
| | - Rob A Bilo
- Specialist Services and Expertise Division, Netherlands Forensic Institute, Laan van Ypenburg 6, 2497, GB, The Hague, the Netherlands
| | - Rick R van Rijn
- Department of Radiology and Nuclear Medicine, Academic Medical Center Amsterdam, Meibergdreef 9, 1105AZ, Amsterdam, the Netherlands.,Specialist Services and Expertise Division, Netherlands Forensic Institute, Laan van Ypenburg 6, 2497, GB, The Hague, the Netherlands
| | - Arjo J Loeve
- Department of BioMechanical Engineering, Faculty of Mechanical, Maritime & Materials Engineering, Delft University of Technology, Mekelweg 2, 2628, CD, Delft, the Netherlands.
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Affiliation(s)
- Peter J Strouse
- Section of Pediatric Radiology, C. S. Mott Children's Hospital, Room 3-231,Department of Radiology, University of Michigan Health System, 1540 E. Hospital Drive, Ann Arbor, MI, 48109-4252, USA.
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6
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Lintern TO, Nash MP, Kelly P, Bloomfield FH, Taberner AJ, Nielsen PMF. Probabilistic description of infant head kinematics in abusive head trauma. Comput Methods Biomech Biomed Engin 2017; 20:1633-1642. [DOI: 10.1080/10255842.2017.1403593] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- T. O. Lintern
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - M. P. Nash
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
- Department of Engineering Science, University of Auckland, Auckland, New Zealand
| | - P. Kelly
- Te Puaruruhau (Child Abuse Assessment Unit), Starship Children’s Hospital, Auckland, New Zealand
| | - F. H. Bloomfield
- Liggins Institute, University of Auckland, Auckland, New Zealand
| | - A. J. Taberner
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
- Department of Engineering Science, University of Auckland, Auckland, New Zealand
| | - P. M. F. Nielsen
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
- Department of Engineering Science, University of Auckland, Auckland, New Zealand
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7
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Jenny CA, Bertocci G, Fukuda T, Rangarajan N, Shams T. Biomechanical Response of the Infant Head to Shaking: An Experimental Investigation. J Neurotrauma 2017; 34:1579-1588. [PMID: 27931172 DOI: 10.1089/neu.2016.4687] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Controversy exists regarding whether violent shaking is harmful to infants in the absence of impact. In this study, our objective was to characterize the biomechanical response of the infant head during shaking through use of an instrumented anthropomorphic test device (commonly referred to as a "crash test dummy" or surrogate) representing a human infant and having improved biofidelity. A series of tests were conducted to simulate violent shaking of an infant surrogate. The Aprica 2.5 infant surrogate represented a 5th percentile Japanese newborn. A 50th percentile Japanese adult male was recruited to shake the infant surrogate in the sagittal plane. Triaxial linear accelerometers positioned at the center of mass and apex of the head recorded accelerations during shaking. Five shaking test series, each 3-4 sec in duration, were conducted. Outcome measures derived from accelerometer recordings were examined for trends. Head/neck kinematics were characterized during shaking events; mean peak neck flexion was 1.98 radians (113 degrees) and mean peak neck extension was 2.16 radians (123 degrees). The maximum angular acceleration across all test series was 13,260 radians/sec2 (during chin-to-chest contact). Peak angular velocity was 105.7 radians/sec (during chin-to-chest contact). Acceleration pulse durations ranged from 72.1 to 168.2 ms. Using an infant surrogate with improved biofidelity, we found higher angular acceleration and higher angular velocity than previously reported during infant surrogate shaking experiments. Findings highlight the importance of surrogate biofidelity when investigating shaking.
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Affiliation(s)
- Carole A Jenny
- 1 Department of Pediatrics, University of Washington School of Medicine , Seattle, Washington
| | - Gina Bertocci
- 2 Department of Bioengineering, University of Louisville , Louisville, Kentucky
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Jones MD, Martin PS, Williams JM, Kemp AM, Theobald P. Development of a computational biomechanical infant model for the investigation of infant head injury by shaking. MEDICINE, SCIENCE, AND THE LAW 2015; 55:291-299. [PMID: 25550310 DOI: 10.1177/0025802414564495] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The inertial loading thresholds for infant head injury are of profound medico-legal and safety-engineering significance. Injurious experimentation with infants is impossible, and physical and computational biomechanical modelling has been frustrated by a paucity of paediatric biomechanical data. This study describes the development of a computational infant model (MD Adams®) by combining radiological, kinematic, mechanical modelling and literature-based data. Previous studies have suggested the neck as critical in determining inertial head loading. The biomechanical effects of varying neck stiffness parameters during simulated shakes were investigated, measuring peak translational and rotational accelerations and rotational velocities at the vertex. A neck quasi-static stiffness of 0.6 Nm/deg and lowest rate-dependent stiffness predisposed the model infant head to the highest accelerations. Plotted against scaled infant injury tolerance curves, simulations produced head accelerations commensurate with those produced during simulated physical model shaking reported in the literature. The model provides a computational platform for the exploitation of improvements in head biofidelity for investigating a wider range of injurious scenarios.
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Affiliation(s)
| | - Philip S Martin
- Cardiff School of Engineering, Cardiff University, Cardiff, UK
| | | | - Alison M Kemp
- Cochrane Institute of Primary Care, Cardiff University, Cardiff, UK
| | - Peter Theobald
- Cardiff School of Engineering, Cardiff University, Cardiff, UK
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9
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Lintern TO, Puhulwelle Gamage NT, Bloomfield FH, Kelly P, Finch MC, Taberner AJ, Nash MP, Nielsen PMF. Head kinematics during shaking associated with abusive head trauma. J Biomech 2015; 48:3123-7. [PMID: 26256822 DOI: 10.1016/j.jbiomech.2015.07.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 07/14/2015] [Indexed: 11/25/2022]
Abstract
Abusive head trauma (AHT) is a potentially fatal result of child abuse but the mechanisms of injury are controversial. To address the hypothesis that shaking alone is sufficient to elicit the injuries observed, effective computational and experimental models are necessary. This paper investigates the use of a coupled rigid-body computational modelling framework to reproduce in vivo shaking kinematics in AHT. A sagittal plane OpenSim computational model of a lamb was developed and used to interpret biomechanical data from in vivo shaking experiments. The acceleration of the head during shaking was used to provide in vivo validation of the associated computational model. Results of this study demonstrated that peak accelerations occurred when the head impacted the torso and produced acceleration magnitudes exceeding 200ms(-)(2). The computational model demonstrated good agreement with the experimental measurements and was shown to be able to reproduce the high accelerations that occur during impact. The biomechanical results obtained with the computational model demonstrate the utility of using a coupled rigid-body modelling framework to describe infant head kinematics in AHT.
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Affiliation(s)
- T O Lintern
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | | | - F H Bloomfield
- Liggins Institute, University of Auckland, Auckland, New Zealand
| | - P Kelly
- Te Puaruruhau (Child Protection Team), Starship Children's Hospital, Auckland, New Zealand
| | - M C Finch
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - A J Taberner
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand; Department of Engineering Science, University of Auckland, Auckland, New Zealand
| | - M P Nash
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand; Department of Engineering Science, University of Auckland, Auckland, New Zealand
| | - P M F Nielsen
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand; Department of Engineering Science, University of Auckland, Auckland, New Zealand.
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McNally DS, Rosenberg NM. MADYMO simulation of children in cycle accidents: a novel approach in risk assessment. ACCIDENT; ANALYSIS AND PREVENTION 2013; 59:469-478. [PMID: 23954681 DOI: 10.1016/j.aap.2013.07.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Revised: 05/23/2013] [Accepted: 07/16/2013] [Indexed: 06/02/2023]
Abstract
Head injuries are a significant cause of death and injury to child cyclists both on and off the road. Current evaluations of the effectiveness of cycle helmets rely on simplified mechanical testing or the analysis of aggregated accident statistics. This paper presents a direct evaluation of helmet efficacy by using computational modelling to simulate a range of realistic accident scenarios, including loss of control, collision with static objects and vehicle impact. A 6-year-old cyclist was modelled (as a Hybrid III 6-year-old dummy), in addition to a typical children's bicycle and a vehicle using the MADYMO dynamics software package. Simulations were performed using ranges of cyclist position, cycle speed and vehicle speed with and without a helmet that meets current standards. Wearing a cycle helmet was found to reduce the probability of head injuries, reducing the average probability of fatality over the scenarios studied from 40% to 0.3%. Similarly, helmet wearing reduced the probability of neck injuries (average probability of fatality reduced from 11% to 1%). There was no evidence that helmet wearing increased the severity of brain or neck injuries caused by rotational accelerations; in fact these were slightly reduced. Similarly, there was no evidence that increased cycling speed, such as might result from helmet related risk compensation, increased the probability of head injury.
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Affiliation(s)
- D S McNally
- Faculty of Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, UK.
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11
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Bradley AL, Swain MV, Neil Waddell J, Das R, Athens J, Kieser JA. A comparison between rib fracture patterns in peri- and post-mortem compressive injury in a piglet model. J Mech Behav Biomed Mater 2013; 33:67-75. [PMID: 23867291 DOI: 10.1016/j.jmbbm.2013.06.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2013] [Revised: 06/02/2013] [Accepted: 06/06/2013] [Indexed: 11/30/2022]
Abstract
OBJECTIVES Forensic biomechanics is increasingly being used to explain how observed injuries occur. We studied infant rib fractures from a biomechanical and morphological perspective using a porcine model. METHODS We used 24, 6th ribs of one day old domestic pigs Sus scrofa, divided into three groups, desiccated (representing post-mortem trauma), fresh ribs with intact periosteum (representing peri-mortem trauma) and those stored at -20°C. Two experiments were designed to study their biomechanical behaviour fracture morphology: ribs were axially compressed and subjected to four-point bending in an Instron 3339 fitted with custom jigs. Morphoscopic analysis of resultant fractures consisted of standard optical methods, micro-CT (μCT) and Scanning Electron Microscopy (SEM). RESULTS During axial compression fresh ribs did not fracture because of energy absorption capabilities of their soft and fluidic components. In flexure tests, dry ribs showed typical elastic-brittle behaviour with long linear load-extension curves, followed by short non-linear elastic (hyperelastic) behaviour and brittle fracture. Fresh ribs showed initial linear-elastic behaviour, followed by strain softening and visco-plastic responses. During the course of loading, dry bone showed minimal observable damage prior to the onset of unstable fracture. Frozen then thawed bone showed similar patterns to fresh bone. Morphologically, fresh ribs showed extensive periosteal damage to the tensile surface with areas of collagen fibre pull-out along the tensile surface. While all dry ribs fractured precipitously, with associated fibre pull-out, the latter feature was absent in thawed ribs. CONCLUSIONS Our study highlights the fact that under controlled loading, fresh piglet ribs (representing perimortem trauma) did not fracture through bone, but was associated with periosteal tearing. These results suggest firstly, that complete lateral rib fracture in infants may in fact not result from pure compression as has been previously assumed; and secondly, that freezing of bone during storage may affect its fracture behaviour.
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Affiliation(s)
- Amanda L Bradley
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Michael V Swain
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - J Neil Waddell
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Raj Das
- Department of Mechanical Engineering, University of Auckland, Auckland, New Zealand
| | - Josie Athens
- Department of Preventive & Social Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Jules A Kieser
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand.
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Sandoz B, Dutshke J, Liu Q, Manavis J, Finnie JW, Vink R, Anderson RWG. In vivo biomechanical response of ovine heads to shaken baby syndrome events. Comput Methods Biomech Biomed Engin 2013; 15 Suppl 1:293-4. [PMID: 23009514 DOI: 10.1080/10255842.2012.713640] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- B Sandoz
- CASR, The University of Adelaide, Adelaide, Australia.
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Bondy M, Altenhof W, Chen X, Snowdon A, Vrkljan B. Development of a finite element/multi-body model of a newborn infant for restraint analysis and design. Comput Methods Biomech Biomed Engin 2012; 17:149-62. [PMID: 22512507 DOI: 10.1080/10255842.2012.672563] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
A finite element/multi-body model of a newborn infant has been developed by researchers at the University of Windsor. The geometry of this model is derived from a Nita newborn hospital training mannequin. It consists of 17 parts: eight upper and lower limb segments, the torso, head, and a seven-segment neck with seven translational and eight rotational joints. Anthropometry is consistent with hospital growth charts, measurements requested from health professionals and data from the open literature. The biomechanical properties of the model (i.e. joint stiffnesses) are implementations of data identified in the open literature. The model has been validated with respect to studies of the biomechanics of shaken baby syndrome, infant falls and the Q0 anthropomorphic testing device. A significant conclusion of this study is that the kinetics of the Q0 neck is not biofidelic. This model is currently used in an analysis of airway patency for infants in modern automotive child restraints.
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Affiliation(s)
- Matthew Bondy
- a Department of Mechanical Engineering , University of Windsor , 401 Sunset Avenue, Windsor Ontario N9B 3P4 , Canada
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14
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Batterbee DC, Sims ND, Becker W, Worden K, Rowson J. Computational model of an infant brain subjected to periodic motion simplified modelling and bayesian sensitivity analysis. Proc Inst Mech Eng H 2011; 225:1036-49. [PMID: 22292202 DOI: 10.1177/0954411911420002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Non-accidental head injury in infants, or shaken baby syndrome, is a highly controversial and disputed topic. Biomechanical studies often suggest that shaking alone cannot cause the classical symptoms, yet many medical experts believe the contrary. Researchers have turned to finite element modelling for a more detailed understanding of the interactions between the brain, skull, cerebrospinal fluid (CSF), and surrounding tissues. However, the uncertainties in such models are significant; these can arise from theoretical approximations, lack of information, and inherent variability. Consequently, this study presents an uncertainty analysis of a finite element model of a human head subject to shaking. Although the model geometry was greatly simplified, fluid-structure-interaction techniques were used to model the brain, skull, and CSF using a Eulerian mesh formulation with penalty-based coupling. Uncertainty and sensitivity measurements were obtained using Bayesian sensitivity analysis, which is a technique that is relatively new to the engineering community. Uncertainty in nine different model parameters was investigated for two different shaking excitations: sinusoidal translation only, and sinusoidal translation plus rotation about the base of the head. The level and type of sensitivity in the results was found to be highly dependent on the excitation type.
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Affiliation(s)
- D C Batterbee
- The University of Sheffield, Department Mechanical Engineering, Sheffield, UK
| | - N D Sims
- The University of Sheffield, Department Mechanical Engineering, Sheffield, UK
| | - W Becker
- The University of Sheffield, Department Mechanical Engineering, Sheffield, UK
| | - K Worden
- The University of Sheffield, Department Mechanical Engineering, Sheffield, UK
| | - J Rowson
- The University of Sheffield, Department Mechanical Engineering, Sheffield, UK
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15
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Lloyd J, Willey EN, Galaznik JG, Lee WE, Luttner SE. Biomechanical Evaluation of Head Kinematics During Infant Shaking Versus Pediatric Activities of Daily Living. ACTA ACUST UNITED AC 2011. [DOI: 10.4303/jfb/f110601] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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16
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Study of an infant brain subjected to periodic motion via a custom experimental apparatus design and finite element modelling. J Biomech 2010; 43:2887-96. [DOI: 10.1016/j.jbiomech.2010.07.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2009] [Revised: 07/15/2010] [Accepted: 07/19/2010] [Indexed: 11/20/2022]
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17
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Postmortem orbital hemorrhage in the investigation of child abuse. Am J Forensic Med Pathol 2010; 31:e7-9. [PMID: 20966739 DOI: 10.1097/paf.0b013e3181ff6212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Child abuse is a leading cause of morbidity and mortality in young children and infants in the United States. Medical care providers, social services, and legal systems make critical decisions regarding injury and history plausibility daily. Injury plausibility judgments rely on evidence-based medicine, individualized experiences, and empirical data. A poor outcome may result if abuse is missed or an innocent family is accused, therefore evidence and science-based injury assessments are required. Although research in biomechanics has improved clinical understanding of injuries in children, much work is still required to develop a more scientific, rigorous approach to assessing injury causation. This article reviews key issues in child abuse and how injury biomechanics research may help improve accuracy in differentiating abuse from accidental events. Case-based biomechanical investigations, human surrogate, and computer modeling biomechanics research applied to child abuse injury are discussed. The goal of this paper is to provide an overview of key research studies rather than on review or commentary articles. Limitations and future research needs are also reviewed.
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Affiliation(s)
- Mary Clyde Pierce
- Department of Pediatrics,University of Louisville, Louisville, Kentucky 40202, USA.
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Ivancevic VG. New mechanics of traumatic brain injury. Cogn Neurodyn 2009; 3:281-93. [PMID: 19031012 PMCID: PMC2727160 DOI: 10.1007/s11571-008-9070-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2008] [Revised: 10/26/2008] [Accepted: 10/26/2008] [Indexed: 10/21/2022] Open
Abstract
The prediction and prevention of traumatic brain injury is a very important aspect of preventive medical science. This paper proposes a new coupled loading-rate hypothesis for the traumatic brain injury (TBI), which states that the main cause of the TBI is an external Euclidean jolt, or SE(3)-jolt, an impulsive loading that strikes the head in several coupled degrees-of-freedom simultaneously. To show this, based on the previously defined covariant force law, we formulate the coupled Newton-Euler dynamics of brain's micro-motions within the cerebrospinal fluid and derive from it the coupled SE(3)-jolt dynamics. The SE(3)-jolt is a cause of the TBI in two forms of brain's rapid discontinuous deformations: translational dislocations and rotational disclinations. Brain's dislocations and disclinations, caused by the SE(3)-jolt, are described using the Cosserat multipolar viscoelastic continuum brain model.
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Affiliation(s)
- Vladimir G Ivancevic
- Land Operations Division, Defence Science & Technology Organisation, Adelaide, SA, Australia,
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Abstract
Shaken baby syndrome is a term often used by physicians and the public to describe abusive head trauma inflicted on infants and young children. Although the term is well known and has been used for a number of decades, advances in the understanding of the mechanisms and clinical spectrum of injury associated with abusive head trauma compel us to modify our terminology to keep pace with our understanding of pathologic mechanisms. Although shaking an infant has the potential to cause neurologic injury, blunt impact or a combination of shaking and blunt impact cause injury as well. Spinal cord injury and secondary hypoxic ischemic injury can contribute to poor outcomes of victims. The use of broad medical terminology that is inclusive of all mechanisms of injury, including shaking, is required. The American Academy of Pediatrics recommends that pediatricians develop skills in the recognition of signs and symptoms of abusive head injury, including those caused by both shaking and blunt impact, consult with pediatric subspecialists when necessary, and embrace a less mechanistic term, abusive head trauma, when describing an inflicted injury to the head and its contents.
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Abstract
Shaken baby syndrome (SBS) is a great concern for forensic nurses. Accurate diagnosis and treatment is essential. The purpose of this report is to review the history of SBS, as well as the physical symptoms of a patient suspected of suffering from this form of abuse. Implications of SBS for the forensic nurse will be presented; this will include the education of families and caregivers and methods of prevention.
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Affiliation(s)
- Megan A Mraz
- Duquesne University, Pittsburgh, Pennsylvania, USA.
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Abstract
OBJECT Falls are the most common accident scenario in young children as well as the most common history provided in child abuse cases. Understanding the biomechanics of falls provides clinicians with objective data to aid in their diagnosis of accidental or inflicted trauma. The objective of this study was to determine impact forces and angular accelerations associated with low-height falls in infants. METHODS An instrumented anthropomorphic infant surrogate was created to measure the forces and 3D angular accelerations associated with falls from low heights (0.3-0.9 m) onto a mattress, carpet pad, or concrete. RESULTS Although height significantly increased peak angular acceleration (alpha(p)), change in peak-to-peak angular velocity, time duration associated with the change in velocity, and peak impact force (F(p)) for head-first drops onto a carpet pad or concrete, none of these variables were significantly affected by height when dropped onto a mattress. The alpha(p) was not significantly different for drops onto a carpet pad and concrete from 0.6 or 0.9 m due to compression of the carpet pad. Surprisingly, sagittal alpha(p) was equaled or surpassed by axial alpha(p). CONCLUSIONS These are the first 3D angular acceleration and impact force data available for head impact in infants from low-height falls. A future study involving a computational model of the infant head will use the loads measured in this study to predict the probability of occipital skull fracture on impact from head-first low-height falls. Together, these studies will provide data that will aid clinicians in the evaluation of accidental and inflicted head injuries, and will contribute to the design of safer environments for children.
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Affiliation(s)
- Brittany Coats
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6321, USA
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Couper Z, Albermani F. Infant brain subjected to oscillatory loading: material differentiation, properties, and interface conditions. Biomech Model Mechanobiol 2007; 7:105-25. [PMID: 17333090 DOI: 10.1007/s10237-007-0079-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2006] [Accepted: 02/09/2007] [Indexed: 11/25/2022]
Abstract
Past research into brain injury biomechanics has focussed on short duration impulsive events as opposed to the oscillatory loadings associated with Shaken Baby Syndrome (SBS). A series of 2D finite element models of an axial slice of the infant head were created to provide qualitative information on the behaviour of the brain during shaking. The test series explored variations in subarachnoid cerebrospinal fluid (CSF) representation, brain matter stiffness, dissipation, and nonlinearity, and differentiation of brain matter type. A new method of CSF modelling based on Reynolds lubrication theory was included to provide a more realistic brain-CSF interaction. The results indicate that solid CSF representation for this load regime misrepresents the phase lag of displacement, and that the volume of subarachnoid CSF, and inclusion of thickness variations due to gyri, are important to the resultant behavior. Stress concentrations in the deep brain are reduced by fluid redistribution and gyral contact, while inclusion of the pia mater significantly reduces cortex contact strains. These results provide direction for future modelling of SBS.
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Affiliation(s)
- Zac Couper
- School of Engineering, University of Queensland, Brisbane 4072, Australia.
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Barnes PD, Krasnokutsky M. Imaging of the central nervous system in suspected or alleged nonaccidental injury, including the mimics. Top Magn Reson Imaging 2007; 18:53-74. [PMID: 17607143 DOI: 10.1097/rmr.0b013e3180d0a455] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Because of the widely acknowledged controversy in nonaccidental injury, the radiologist involved in such cases must be thoroughly familiar with the imaging, clinical, surgical, pathological, biomechanical, and forensic literature from all perspectives and with the principles of evidence-based medicine. Children with suspected nonaccidental injury versus accidental injury must not only receive protective evaluation but also require a timely and complete clinical and imaging workup to evaluate pattern of injury and timing issues and to consider the mimics of abuse. All imaging findings must be correlated with clinical findings (including current and past medical record) and with laboratory and pathological findings (eg, surgical, autopsy). The medical and imaging evidence, particularly when there is only central nervous system injury, cannot reliably diagnose intentional injury. Only the child protection investigation may provide the basis for inflicted injury in the context of supportive medical, imaging, biomechanical, or pathological findings.
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