Child occupant injury risk in rear impact and frontal impact: effect of impact conditions and occupant related factors

Injury claims associated with minimal damage rear impact traffic crashes are often defended using a “biomechanical approach,” in which the occupant forces of the crash are compared to the forces of activities of daily living (ADLs), resulting in the conclusion that the risk of injury from the crash is the same as for ADLs. The purpose of the present investigation is to evaluate the scientific validity of the central operating premise of the biomechanical approach to injury causation; that occupant acceleration is a scientifically valid proxy for injury risk. Data were abstracted, pooled, and compared from three categories of published literature: (1) volunteer rear impact crash testing studies, (2) ADL studies, and (3) observational studies of real-world rear impacts. We compared the occupant accelerations of minimal or no damage (i.e., 3 to 11 kph speed change or “delta V”) rear impact crash tests to the accelerations described in 6 of the most commonly reported ADLs in the reviewed studies. As a final step, the injury risk observed in real world crashes was compared to the results of the pooled crash test and ADL analyses, controlling for delta V. The results of the analyses indicated that average peak linear and angular acceleration forces observed at the head during rear impact crash tests were typically at least several times greater than average forces observed during ADLs. In contrast, the injury risk of real-world minimal damage rear impact crashes was estimated to be at least 2000 times greater than for any ADL. The results of our analysis indicate that the principle underlying the biomechanical injury causation approach, that occupant acceleration is a proxy for injury risk, is scientifically invalid. The biomechanical approach to injury causation in minimal damage crashes invariably results in the vast underestimation of the actual risk of such crashes, and should be discontinued as it is a scientifically invalid practice.

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An overview on pedestrians involved in traffic accidents in Latvia: Years 2010-2014

SHS Web of Conferences ◽

10.1051/shsconf/20184001004 ◽

2018 ◽

Vol 40 ◽

pp. 01004 ◽

Cited By ~ 1

Author(s):

A. Bukova-Zideluna ◽

A. Villerusa ◽

A. Lama

Keyword(s):

Injury Risk ◽

Traffic Accidents ◽

Road Traffic ◽

Capital City ◽

Winter Period ◽

Fatality Rate ◽

Road Traffic Accidents ◽

Related Factors ◽

The Road ◽

Adverse Weather

Latvian national road accident statistics shows that for the vulnerable road users’ situation is critical, since pedestrians are involved in more than a quarter of road traffic accidents. This paper gives an analysis on pedestrians involved in road traffic accidents based on the road safety accident database in Latvia for the years 2010–2014. The total number of cases does not change significantly, however there has been an increase in pedestrian fatality rates over the period. From the total number of traffic accidents with pedestrians involved 92.4% had injuries, 6.8% were lethal cases and others didn't suffer from injuries. Out of 342 fatalities 37.7% occurred during the winter period, 56.1% in adverse weather (overcast, fog, rain or snow), 69.9% during twilight or darkness and 26.9% on weekends. Out of all accidents 55.3% occurred in the capital city Riga, but fatality rate was higher on main state roads. 8.1% of the total number of pedestrians involved in road traffic accidents was found to have alcohol in their blood right after the road traffic accident. Fatality rate was higher for those with exceeded BAC. Pedestrian injury risk analysis was associated with demographical and traffic-related factors, urbanization, visibility and seasonal patterns.

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Investigation of chest biomechanical response by variation of restraint loads in frontal impact

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/0954407019881067 ◽

2019 ◽

Vol 234 (5) ◽

pp. 1377-1388

Author(s):

Sen Xiao ◽

Yanchao Qie ◽

Wu Chen ◽

Jikuang Yang ◽

Jeff R Crandall

Keyword(s):

Injury Risk ◽

Injury Severity ◽

Peak Load ◽

Chest Injury ◽

Frontal Impact ◽

Design And Optimization ◽

Load Paths ◽

Load Factors ◽

Deflection Analysis ◽

Injury Outcomes

The seatbelt restraint load is one of the primary sources of occupant chest injury. Thus, studying the different biomechanical responses of chest by varying the seatbelt loads will result in a significant improvement in seatbelt protection performance. Based on the high-biofidelity mechanical dummy model, a sled-dummy test was conducted to investigate the differences in chest injury outcomes caused by the variation of seatbelt load paths or load processes. The chest kinematics and kinetics are compared to determine the influence of load factors on these biomechanical outcomes. Results show that chest injury severity has a positive nonlinear correlation with impact speed. However, the injury risk is mainly determined by the seatbelt peak load in the chest deflection analysis. The results of this study can provide a reference to seatbelt safety design and optimization. The model and method can be used in other research works on the biomechanics of frontal impact.

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Study on the Difference of Frontal Impact Response among People of Different Sizes

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.34-35.111 ◽

2010 ◽

Vol 34-35 ◽

pp. 111-116 ◽

Cited By ~ 1

Author(s):

Li Bo Cao ◽

Chong Zhen Cui ◽

Ning Yu Zhu ◽

Huan Chen

Keyword(s):

Human Body ◽

Injury Risk ◽

Simulation Models ◽

Restraint System ◽

Frontal Impact ◽

Occupant Restraint System ◽

Impact Simulation ◽

The Difference ◽

Human Body Models ◽

Multi Body

In this article, seven frontal impact simulation models with same restraint system and different human body models were established through the use of multi-body kinematics software MADYMO. The injuries in head, chest and femurs of different human models and the differences of these injuries were analyzed in detail. The weighted injury criterion was adopted to evaluate the overall injuries of different human body models. The results shows that the injury risk of smaller human body is much higher than the taller human body, and existing occupant restraint system that protects the 50th percentile American occupant well protects other size occupant poorly.

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Rider Stature Influence to Injury Risk in Motorcycle Rear Impact to Car

10.4271/2019-01-1436 ◽

2019 ◽

Cited By ~ 2

Author(s):

Wenle Lv ◽

Ludek Hyncik ◽

Tomasz Bonkowski

Keyword(s):

Injury Risk ◽

Rear Impact

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Occupant injury risk analysis at NASS/CDS database

International Journal of Automotive Technology ◽

10.1007/s12239-017-0083-8 ◽

2017 ◽

Vol 18 (5) ◽

pp. 851-860

Author(s):

Hyung Yun Choi ◽

Jaeho Shin ◽

Chang Jin Oh ◽

Jin Ho Bae

Keyword(s):

Risk Analysis ◽

Injury Risk ◽

Occupant Injury

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Development of a wheelchair occupant injury risk assessment method and its application in the investigation of wheelchair securement point influence on frontal crash safety

IEEE Transactions on Rehabilitation Engineering ◽

10.1109/86.830957 ◽

2000 ◽

Vol 8 (1) ◽

pp. 126-139 ◽

Cited By ~ 7

Author(s):

G.E. Bertocci ◽

D.A. Hobson ◽

K.H. Digges

Keyword(s):

Risk Assessment ◽

Injury Risk ◽

Assessment Method ◽

Frontal Crash ◽

Crash Safety ◽

Risk Assessment Method ◽

Occupant Injury

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A Peak-Selection RBF Mesh Morphing Method for Subject-Specific Child Occupant Modeling

Volume 13: Design, Reliability, Safety, and Risk ◽

10.1115/imece2018-88398 ◽

2018 ◽

Author(s):

Yunlei Yin ◽

Wenxiang Dong ◽

Zhenfei Zhan ◽

Junming Li

Keyword(s):

Finite Element ◽

Motor Vehicle ◽

Mesh Morphing ◽

Subject Specific ◽

Radial Basis ◽

Occupant Injury ◽

Optimal Kernel ◽

Child Occupant ◽

Specific Modeling ◽

Important Significance

The mesh morphing method is widely applied in building subject-specific human finite element models. However, there are many problems yet to be resolved when applying the mesh morphing method in subject-specific modeling, such as calculation difficulties and low morphing accuracy. To solve these problems above, an efficient peak-selection RBF mesh morphing method is proposed in the paper. Firstly, by comparing different types of radial basis functions, an optimal kernel function is selected to improve morphing accuracy. Secondly, the landmarks are reduced by selecting multiple peak nodes from the object surfaces, so as to reduce iteration steps and improve the mesh generation efficiency. The proposed peak-selection Radial Basis Function (RBF) mesh morphing method is further demonstrated through a subject-specific child finite element modeling problem. This mesh morphing method has important significance for analyzing the occupant injury of different body features in motor vehicle crashes.

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An Optimization Design of Knee Airbag for Driver Protection from Inter-City Coach Frontal Impact

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.945-949.40 ◽

2014 ◽

Vol 945-949 ◽

pp. 40-43

Author(s):

Han Yu Wang ◽

Ji Kuang Yang ◽

Xiao Qing Jiang ◽

Li Li

Keyword(s):

Genetic Algorithms ◽

Lower Extremity ◽

Mathematical Models ◽

Optimization Design ◽

Injury Risk ◽

Influence Factors ◽

Lower Extremities ◽

Design Parameters ◽

Frontal Impact ◽

Multi Objective

In order to reduce the injury risk of driver’s lower extremities, a driver knee airbag was developed and optimized by using mathematical models. The influence of eight design parameters of belt and knee airbag on the injuries of driver’s lower extremities was analyzed. The result shows that the key influence factors are sensitive to the injuries of lower extremity, including initiation timing of knee airbag, the strap length of knee airbag and area coefficient for the exhaust openings of knee airbag. Based on multi-objective genetic algorithms, an optimization of the knee airbag was conducted in terms of the three factors. After optimization, the injury risk of driver’s lower extremities is greatly reduced.

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Head-turned rear impact causing dynamic cervical intervertebral foramen narrowing: implications for ganglion and nerve root injury

Journal of Neurosurgery Spine ◽

10.3171/spi.2006.4.5.380 ◽

2006 ◽

Vol 4 (5) ◽

pp. 380-387 ◽

Cited By ~ 16

Author(s):

Yasuhiro Tominaga ◽

Travis G. Maak ◽

Paul C. Ivancic ◽

Manohar M. Panjabi ◽

Bryan W. Cunningham

Keyword(s):

Nerve Root ◽

Injury Risk ◽

Compression Injury ◽

Nerve Root Injury ◽

Rear Impact ◽

Cervical Ganglion ◽

Spine Model ◽

Continuous Dynamic ◽

Rear Impacts ◽

The Right

Object A rotated head posture at the time of vehicular rear impact has been correlated with a higher incidence and greater severity of chronic radicular symptoms than accidents occurring with the occupant facing forward. No studies have been conducted to quantify the dynamic changes in foramen dimensions during head-turned rear-impact collisions. The objectives of this study were to quantify the changes in foraminal width, height, and area during head-turned rear-impact collisions and to determine if dynamic narrowing causes potential cervical nerve root or ganglion impingement. Methods The authors subjected a whole cervical spine model with muscle force replication and a surrogate head to simulated head-turned rear impacts of 3.5, 5, 6.5, and 8 G following a noninjurious 2-G baseline acceleration. Continuous dynamic foraminal width, height, and area narrowing were recorded, and peaks were determined during each impact; these data were then statistically compared with those obtained at baseline. The authors observed significant increases (p < 0.05) in mean peak foraminal width narrowing values greater than baseline values, of up to 1.8 mm in the left C5–6 foramen at 8 G. At the right C2–3 foramen, the mean peak dynamic foraminal height was significantly narrower than baseline when subjected to rear-impacts of 5 and 6.5 G, but no significant increases in foraminal area were observed. Analysis of the results indicated that the greatest potential for cervical ganglion compression injury existed at C5–6 and C6–7. Greater potential for ganglion compression injury existed at C3–4 and C4–5 during head-turned rear impact than during head-forward rear impact. Conclusions Extrapolation of present results indicated potential ganglion compression in patients with a non-stenotic foramen at C5–6 and C6–7; in patients with a stenotic foramen the injury risk greatly increases and spreads to include the C3–4 through C6–7 as well as C4–5 through C6–7 nerve roots.

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