Preservatives for postmortem brain tissue in biomechanical testing: A pilot study.

Postmortem human subject (PMHS) studies are essential to brain injury research in motor vehicle safety. However, postmortem deterioration reduces the similarity between postmortem test results and in vivo response in material testing of brain tissue and in biomechanical testing of the whole head. This pilot study explores the effect of potential preservatives on brain tissue breakdown to identify promising preservatives that warrant further investigation.

Biofidelity assessment of the GHBMC M50-O in a rear-facing seat configuration during high-speed frontal impact.

The objective of this study was to assess the biofidelity of the Global Human Body Models Consortium (GHBMC) 50 male (M50-O) v6.0 seated in an upright (25-degree recline) all-belts-to-seat (ABTS) in a 56 km/h rear-facing frontal impact. The experimental boundary conditions from the post-mortem human subjects (PMHS) tests were replicated in the computational finite element (FE) environment.

Thoracic responses and injuries to male postmortem human subjects (PMHS) in rear-facing seat configurations in high-speed frontal impacts.

One potential nonstandard seating configuration for vehicles with automated driving systems (ADS) is a reclined seat that is rear-facing when in a frontal collision. There are limited biomechanical response and injury data for this seating configuration during high-speed collisions. The main objective of this study was to investigate thoracic biomechanical responses and injuries to male postmortem human subjects (PMHS) in a rear-facing scenario with varying boundary conditions.

Abdominal biofidelity assessment of 5th percentile female ATD responses relative to recently developed belt and bar loading corridors.

Objective: The objective of this study was the quantitative evaluation and comparison of the responses of the Hybrid III 5th percentile female (HIII-05F) and the 5th percentile female Test Device for Human Occupant Restraint (THOR-05F) anthropomorphic test devices (ATDs) subjected to abdominal loading conditions.

Method: The HIII-05F and THOR-05F were subjected to 3 different abdominal loading conditions: fixed-back belt pull (low compression), fixed-back belt pull (high compression), and free-back rigid bar impact at 6 m/s. The stroke of the impact was controlled to represent injurious and noninjurious loading conditions as observed in the experiments with postmortem human subjects (PMHS).

Analysis of injury mechanism and thoracic response of elderly, small female PMHS in near-side impact scenarios.

Objective: In 2020, 17% of all crash fatalities were individuals aged 65 years or older. Crash data also revealed that for older occupants, thoracic related injuries are among the leading causes of fatality. Historically, the majority of near-side impact postmortem human subjects (PMHS) studies used a generic load wall to capture external loads that were applied to PMHS.

Comparison of small female PMHS thoracic responses to scaled response corridors in a frontal hub impact.

Objective: The purpose of this study was to generate biomechanical response corridors of the small female thorax during a frontal hub impact and evaluate scaled corridors that have been used to assess biofidelity of small female anthropomorphic test devices (ATDs) and human body models (HBMs).

Methods: Three small female postmortem human subjects (PMHS) were tested under identical conditions, in which the thorax was impacted using a 14.0 kg pneumatic impactor at an impact velocity of 4.

Biomechanical Responses and Injury Assessment of Post Mortem Human Subjects in Various Rear-facing Seating Configurations.

The objective of this study was to generate biomechanical corridors from post-mortem human subjects (PMHS) in two different seatback recline angles in 56 km/h sled tests simulating a rear-facing occupant during a frontal vehicle impact. PMHS were placed in a production seat which included an integrated seat belt. To achieve a repeatable configuration, the seat was rigidized in the rearward direction using a reinforcing frame that allowed for adjustability in both seatback recline angle and head restraint position.

Biomechanical Response Targets of Adult Human Ribs in Frontal Impacts.

Thorax injuries mainly due to rib fractures have been associated with high rates of morbidity and mortality in motor vehicle crashes. Thoracic biomechanics has been studied extensively, but there are no robust biomechanical response targets for ribs that consider age, sex, body size, and vulnerability factors. The objective of this study was to generate biomechanical targets for human rib response with respect to age, sex, and body size.

A Novel Approach to Scaling Age-, Sex-, and Body Size-Dependent Thoracic Responses using Structural Properties of Human Ribs.

Thoracic injuries are frequently observed in motor vehicle crashes, and rib fractures are the most common of those injuries. Thoracic response targets have previously been developed from data obtained from post-mortem human subject (PMHS) tests in frontal loading conditions, most commonly of mid-size males. Traditional scaling methods are employed to identify differences in thoracic response for various demographic groups, but it is often unknown if these applications are appropriate, especially considering the limited number of tested PMHS from which those scaling factors originate.

Quantification of Skeletal and Soft Tissue Contributions to Thoracic Response in a Dynamic Frontal Loading Scenario.

Thoracic injuries continue to be a major health concern in motor vehicle crashes. Previous thoracic research has focused on 50 percentile males and utilized scaling techniques to apply results to different demographics. Individual rib testing offers the advantage of capturing demographic differences; however, understanding of rib properties in the context of the intact thorax is lacking.

Sources of Variability in Structural Bending Response of Pediatric and Adult Human Ribs in Dynamic Frontal Impacts.

Despite safety advances, thoracic injuries in motor vehicle crashes remain a significant source of morbidity and mortality, and rib fractures are the most prevalent of thoracic injuries. The objective of this study was to explore sources of variation in rib structural properties in order to identify sources of differential risk of rib fracture between vehicle occupants. A hierarchical model was employed to quantify the effects of demographic differences and rib geometry on structural properties including stiffness, force, displacement, and energy at failure and yield.

Biofidelity Evaluation of the THOR and Hybrid III 50 Percentile Male Frontal Impact Anthropomorphic Test Devices.

The objective of this study is to present a quantitative comparison of the biofidelity of the THOR and Hybrid III 50 percentile male ATDs. Quantitative biofidelity was assessed using NHTSA's Biofidelity Ranking System in a total of 21 test conditions, including impacts to the head, face, neck, upper thorax, lower oblique thorax, upper abdomen, lower abdomen, femur, knee, lower leg, and whole-body sled tests to evaluate upper body kinematics and thoracic response under frontal and frontal oblique restraint loading. Biofidelity Ranking System scores for THOR were better (lower) than Hybrid III in 5 of 7 body regions for internal biofidelity and 6 of 7 body regions for external biofidelity.

Rib Geometry Explains Variation in Dynamic Structural Response: Potential Implications for Frontal Impact Fracture Risk.

The human thorax is commonly injured in motor vehicle crashes, and despite advancements in occupant safety rib fractures are highly prevalent. The objective of this study was to quantify the ability of gross and cross-sectional geometry, separately and in combination, to explain variation of human rib structural properties. One hundred and twenty-two whole mid-level ribs from 76 fresh post-mortem human subjects were tested in a dynamic frontal impact scenario.

Evaluation of a coplanar 6a3ω configuration in the Hybrid III 50th percentile male head.

Objectives: In order to understand the mechanisms of traumatic brain injury (TBI) and develop proper safety measures, it is essential that accurate instrumentation methods are utilized. The brain injury criterion (BrIC) has been developed and validated to predict brain injuries in combination with the head injury criterion (Takhounts et al. 2011, 2013).

Opportunities for crash and injury reduction: A multiharm approach for crash data analysis.

Objective: A multiharm approach for analyzing crash and injury data was developed for the ultimate purpose of getting a richer picture of motor vehicle crash outcomes for identifying research opportunities in crash safety.

Methods: Methods were illustrated using a retrospective analysis of 69,597 occupant cases from NASS CDS from 2005 to 2015. Occupant cases were analyzed by frequency and severity of outcome: fatality, injury by Abbreviated Injury Scale (AIS), number of cases, attributable fatality, disability, and injury costs.

Male and female WorldSID and post mortem human subject responses in full-scale vehicle tests.

Objective: This study compares the responses of male and female WorldSID dummies with post mortem human subject (PMHS) responses in full-scale vehicle tests.

Methods: Tests were conducted according to the FMVSS-214 protocols and using the U.S.

The Large Omnidirectional Child (LODC) ATD: Biofidelity Comparison with the Hybrid III 10 Year Old.

When the Hybrid III 10-year old (HIII-10C) anthropomorphic test device (ATD) was adopted into Code of Federal Regulations (CFR) 49 Part 572 as the best available tool for evaluating large belt-positioning booster seats in Federal Motor Vehicle Safety Standard (FMVSS) No. 213, NHTSA stated that research activities would continue to improve the performance of the HIII-10C to address biofidelity concerns. A significant part of this effort has been NHTSA's in-house development of the Large Omnidirectional Child (LODC) ATD.

Biomechanical Responses of PMHS Subjected to Abdominal Seatbelt Loading.

Past studies have found that a pressure based injury risk function was the best predictor of liver injuries due to blunt impacts. In an effort to expand upon these findings, this study investigated the biomechanical responses of the abdomen of post mortem human surrogates (PMHS) to high-speed seatbelt loading and developed external response targets in conjunction with proposing an abdominal injury criterion. A total of seven unembalmed PMHS, with an average mass and stature of 71 kg and 174 cm respectively were subjected to belt loading using a seatbelt pull mechanism, with the PMHS seated upright in a freeback configuration.

Age and sex alone are insufficient to predict human rib structural response to dynamic A-P loading.

Thoracic injuries from motor vehicle crashes (MVCs) are common in children and the elderly and are associated with a high rate of mortality for both groups. Rib fractures, in particular, are linked to high mortality rates which increase with the number of fractures sustained. Anthropomorphic test devices (ATDs) and computational models have been developed to improve vehicle safety, however these tools are constructed based on limited physical datasets.

The effect of age on the structural properties of human ribs.

Traumatic injury from motor vehicle crashes is a major cause of morbidity and mortality in the United States. The thorax is particularly at risk in motor vehicle crashes and is studied extensively by the injury biomechanics community. Unfortunately, most samples used in such research generally do not include children or the very elderly, despite the common occurrence of thorax injuries at both ends of the age spectrum.

Development of brain injury criteria (BrIC).

Rotational motion of the head as a mechanism for brain injury was proposed back in the 1940s. Since then a multitude of research studies by various institutions were conducted to confirm/reject this hypothesis. Most of the studies were conducted on animals and concluded that rotational kinematics experienced by the animal's head may cause axonal deformations large enough to induce their functional deficit.

The response of pediatric ribs to quasi-static loading: mechanical properties and microstructure.

Traumatic injury is a major cause of death in the child population. Motor vehicle crashes account for a large portion of these deaths, and a considerable effort is put forth by the safety community to identify injury mechanisms and methods of injury prevention. However, construction of biofidelic anthropomorphic test devices and computational models for this purpose requires knowledge of bone properties that is difficult to obtain.

Comparison of cervical vertebrae rotations for PMHS and BioRID II in rear impacts.

Objective: The objectives of this study are to propose a new instrumentation technique for measuring cervical spine kinematics, validate it, and apply the instrumentation technique to postmortem human subjects (PMHS) in rear impact sled tests so that cervical motions can be investigated.

Methods: First, a new instrumentation and dissection technique is proposed in which instrumentation (3 accelerometers, 3 angular rate sensors) capable of measuring the detailed intervertebral kinematics are installed on the anterior aspects of each vertebral body with minimal muscular damage. The instrumentation was validated by conducting 10 km/h rear impact tests with 2 PMHS in a rigid rolling chair.

Evaluation of the internal and external biofidelity of current rear impact ATDs to response targets developed from moderate-speed rear impacts of PMHS.

The goal of this study is to evaluate both the internal and external biofidelity of existing rear impact anthropomorphic test devices (BioRID II, RID3D, Hybrid III 50th) in two moderate-speed rear impact sled test conditions (8.5g, 17 km/h; 10.5g, 24 km/h) by quantitatively comparing the ATD responses to biomechanical response targets developed from PMHS testing in a corresponding study.

Biomechanical responses of PMHS in moderate-speed rear impacts and development of response targets for evaluating the internal and external biofidelity of ATDS.

The objectives of this study were to obtain biomechanical responses of post mortem human subjects (PMHS) by subjecting them to two moderate-speed rear impact sled test conditions (8.5g, 17 km/h; 10.5g, 24 km/h) while positioned in an experimental seat system, and to create biomechanical targets for internal and external biofidelity evaluation of rear impact ATDs.