Risk Of Neck Injury Research Articles

Safety of active pre-collision seat rotation strategies for autonomous vehicles: injury risk evaluation of occupant’s neck

The development of autonomous driving technology has engendered new requirements for the safety of the occupants of autonomous vehicles. Different variants of seat configurations, including face-to-face rides and rotating seats, have been implemented in autonomous vehicles. Furthermore, pre-collision active seat rotation strategies have been proposed for the safety of the occupants of autonomous vehicles. However, further evaluations are required to determine whether the active seat rotation strategy could cause injuries to the occupants during a significantly rapid rotation process. In this study, two types of multi-rigid body seat-occupant models and a finite element model of the occupant’s cervical spine were designed. The validity of the multi-rigid body model for the seat occupant was verified through a frontal collision simulation test. Considering the influence of different seat types and rotation directions on the risk of neck injuries to the occupants, four simulations were conducted based on the condition that the seat rotated by 90° in 200 ms. The kinematic and biomechanical aspects of the risk of injuries to the occupant’s cervical spine during the active seat rotation strategy were assessed, and the essential causes of these injuries were discussed. The results indicate that, in the absence of leg baffles and foot supports, seat rotation toward the diagonal line of the seatbelt poses different degrees of risk of injuries to the cervical spine, platysma, sternocleidomastoid, common carotid artery, external jugular vein, and internal jugular vein. Therefore, the seats of highly or fully autonomous vehicles should be designed to prevent this scenario.

Neck Loads During Head-First Entries into Trampoline Dismount Foam Pits: Considerations for Trampoline Park Safety

Serious cervical spine injuries have been documented from falls into foam pits at trampoline parks. To address the lack of evidence on how foam pits should be designed for mitigating neck injury risk, this study aimed to quantify neck loads during head-first entry into varying foam pit designs. An instrumented Hybrid III anthropomorphic test device was dropped head-first from a height of up to 1.5 m into three differently constructed foam pits, each using a different mechanism to prevent direct contact between the falling person and the floor (foam slab, trampoline or net bed). Measured neck loads were compared to published injury reference values. In the simplest, foam-only pit design, increasing foam depth tended to reduce peak compressive force. At least one injury assessment reference metric was exceeded in all pit conditions tested for 1.5 m falls, most commonly the time-dependent neck compression criterion. The results highlight the importance of adequate foam depth in combination with appropriate pit design in minimizing injury risk. The risk of cervical spine injury may not be reduced sufficiently with current foam pit designs.

Development of Biomechanical Computational Models of Six-Year-Old Child Occupant with Different Sitting Postures and Application in the Study of Whiplash Injuries

<div class="section abstract"><div class="htmlview paragraph">With the development of intelligent cockpit, child occupants will engage in traffic operation in various sitting postures. Therefore, studying the mechanism and risk of whiplash injury of child occupants with different sitting postures has important application value for the research and development of child restraint system. In this study, the 120° and 135° sitting postures of six-year-old child occupant were developed based on the validated 105° sitting posture finite element model with detailed anatomical structure. The whiplash test in Euro NCAP was reconstructed to evaluate the influence of sitting posture angle on the risk of whiplash injury. In the three groups of simulation experiments, the Upper Neck Tension (Fz) was far less than the higher limit of Euro NCAP evaluation although the Fz value increased as the upper torso angle increases. However, the Upper Neck Shear (Fx) and Neck Injury Criterion (NIC) values from the 105° sitting posture exceeded the higher limit of Euro NCAP by 124% and 9%, respectively，increasing the risk of slight neck injury. Neck Protection Criteria (N<sub>km</sub>), NIC, cervical spine stress, and spinal cord stress from 120° sitting posture decreased by 23%, 42%, 56.9%, and 41.1%, respectively, compared with those parameters from the child standard sitting posture (105°). However, the Fx value from 120° sitting posture exceeded the higher limit by 101%; a slight risk of neck injury thus still exists. These assessment parameters from 135° sitting posture decreased by 60%, 50%, 77.6% and 43.6%, respectively, and the parameters were all lower than the higher limit of Euro NCAP. In addition, the maximum von Mises stress was mainly concentrated at the contact position between atlas and axial odontoid (105° and 120° postures) and the posterior arch of atlas with axial odontoid (135° postures). In conclusion, the risk of whiplash injury decreased with the increase of upper torso angle.</div></div>

A Computational Framework for Human-Centric Vehicular Crashworthiness Design and Decision-Making Under Uncertainty

Abstract Government agencies, globally, strive to minimize the likelihood and frequency of human death and severe injury on road transport systems. From an engineering design standpoint, the minimization of these road accident effects on occupants becomes a critical design goal. This necessitates the quantification and management of injury risks on the human body in response to several vehicular impact variables and their associated uncertainties for different crash scenarios. In this paper, we present a decision-based, robust design (RD) framework to quantify and manage the impact-based injury risks on occupants for different computational model-based car crash scenarios. The key functionality offered is the designer's capability to conduct robust concept exploration focused on managing the selected impact variables and associated uncertainties, such that injury risks are controlled within acceptable levels. The framework's efficacy is tested for near-side impact scenarios with impact velocity and angle of impact as the critical variables of interest. Two injury criteria, namely, head injury criterion (HIC) and lateral neck injury criteria (Lateral Nij) are selected to quantitatively measure the head and neck injury risks in each crash simulation. Using the framework, a RD problem is formulated to determine the combination of impact variables that best satisfies the injury goals defined. The framework and associated design constructs are generic and support the formulation and decision-based robust concept exploration of similar problems involving models under uncertainty. Our focus in this paper is on the framework rather than the results per se.

National Athletic Trainers' Association Position Statement: Reducing Intentional Head-First Contact Behavior in American Football Players.

To provide evidence-based recommendations for reducing the prevalence of head-first contact behavior in American football players with the aim of reducing the risk of head and neck injuries. In American football, using the head as the point of contact is a persistent, well-documented, and direct cause of catastrophic head and cervical spine injury. Equally concerning is that repeated head-impact exposures are likely to result from head-first contact behavior and may be associated with long-term neurocognitive conditions such as dementia, depression, and chronic traumatic encephalopathy. The National Athletic Trainers' Association proposes 14 recommendations to help the certified athletic trainer, allied health care provider, coach, player, parent, and broader community implement strategies for reducing the prevalence of head-first contact in American football.

The ultimate guide to posture: A review

Postural alignment is the composite of the position of all joint and limbs of the body at any given movement. Optimal alignment is a prerequisite for optimal movement function. Postural control is the ability to control of the body’s position in space for stability and orientation. Postural orientation is the ability to maintain normal alignment relationships between the various body segments and between the body and environment. Methodology: The author conducted a comprehensive search of open access articles of major scientific databases including PuBMed, Scopus, Web of Science, shodhganga, Google Scholar etc. Ten significant scientific studies were found relating to the ultimate guide to posture. Five studies were selected based on inclusion criteria. Results Helps reduce the risk of neck injuries and back pain. Minimizes fatigue and pain from aching joints. Prevents improper spinal alignment, which can lead to headaches and discomfort. Improves your self-esteem. Conclusions: A faulty idea of correct posture can be cured by including the patient to accept a new and satisfactory pattern and then by teaching him how to assume it and make it habitual by repeated voluntary effort.

Cervical Muscle Activation Characteristics and Head Kinematics in Males and Females Following Acoustic Warnings and Impulsive Head Forces.

Sex, head and neck posture, and cervical muscle preparation are contributing factors in the severity of head and neck injuries. However, it is unknown how these factors modulate the head kinematics. In this study, twenty-four (16 male and 8 female) participants experienced 50 impulsive forces to their heads with and without an acoustic warning. Female participants demonstrated a 71 ms faster (p = 0.002) muscle activation onset compared to males after warning. The magnitude of muscle activation was not significant between sexes. Females exhibited 21% (p < 0.008) greater peak angular velocity in all force directions and 18% (p < 0.04) greater peak angular acceleration in sagittal plane compared to males. Females exhibited 15% (p = 0.03) greater peak linear acceleration compared to males only in sagittal flexion. Preparation attenuated head kinematics significantly (p < 0.03) in 11 out of 18 investigated head kinematics for both sexes. A warning eliciting a startle response 420 ms prior to the impact resulted in significant attenuation of all measured head kinematics in sagittal extension (p < 0.037). In conclusion, both sex and warning type were significant factors in head kinematics. These data provide insight into the complex relationship of muscle activation and sex, and may help identify innovative strategies to reduce head and neck injury risk in sports.

Influential crash conditions leading to injury differences experienced by female and male drivers

IntroductionRobust occupant protection is critical for the longevity and quality of life of the diverse driving population. Studies have shown that the vehicle crash testing process has greatly assisted in decreasing the severity of injuries experienced by occupants. However, female occupants are not equitably accounted for in the current testing processes while experiencing a significantly increased risk of higher severity injuries compared to male occupants in comparable crash conditions. Given the increased safety concern for female occupants, it is critical to investigate the conditions that result in injuries occurring in specific locations in cases of female occupants compared to male occupants. MethodsIn this study, an investigation is made to uncover potential influential crash conditions that lead to injury location differences experienced by female and male drivers using a novel linked dataset of emergency medical services and crash data. Logistic regression methods were used to develop robust analyses. ResultsThe results revealed that female and male drivers experience injuries in different locations to a significant degree depending upon vehicle model year, airbag deployment, and driver age when considering all crash types. The results included the finding that as vehicle model year increases, neck injury risk decreases for male drivers while it increases for female drivers. ConclusionsThis study highlighted the crash conditions and vehicle components that lead to different injury outcomes for female and male drivers. From a policy perspective, the results emphasize the importance of including both representative female and male anthropometry in vehicle testing and design. From a practitioner and research perspective, this study provides the data needed to understand the components of vehicle design that must be further considered to provide optimal occupant protection for the entire driving population, leading to more equitable, positive long-term health outcomes for all drivers.

A high-fidelity human cervical muscle finite element model for motion and injury studies

Abstract Active muscle response is a key factor in the motion and injury of the human head and neck. Due to the limitations of experimentation and the shortcomings of previous finite element models, the influence of material parameters of cervical muscle on motions of the head and neck during a car crash have not been comprehensively investigated. In the present work, a model of the cervical muscle in a 50th-percentile adult male was constructed. The muscles were modelled using solid finite elements, with a nonlinear-elastic and viscoelastic material and a Hill material modelling the passive and active parts of each muscle, respectively. The head dynamic responses of the model were validated using results obtained from volunteer sled tests. The influence of the material parameters of a muscle on head and neck motions were determined. Our key finding was that the greater the stiffness and the contraction strength of the neck muscles, the smaller the rotation angle of the head and the neck, and, hence, the lower the risk of head and neck injury to occupants in a car crash.

Using Wearable Technology to Measure the Association Between Neck Posture and Pain During Urologic Open and Robotic Surgery.

Purpose: Chronic neck pain is the most prevalent work-related musculoskeletal injury among surgeons. Urologists may be at higher risk of neck injury due to extended time spent operating in deep anatomical structures during open surgery. Our goal was to use wearable technology to quantify the relationship between neck posture and pain during open and robotic surgery. Materials and Methods: Urologic attendings and residents who spent at least 1 day per week performing surgery for >6 hours took part in this study. Neck posture was measured in real time during surgery using inertial measurement devices attached at the occipital protuberance and seventh cervical vertebrae. Self-reported neck pain scores were obtained throughout their workday. Results: Thirty participants and 202 hours of surgery were included in the study (21 attendings, 9 residents). There was a significant association between neck posture and pain (p = 0.04). Surgeons performing open procedures spent on average 147 minutes with their head in neck flexion postures of 30° or greater compared with 68 minutes for those performing robotic procedures (p = 0.007). Surgeons performing open procedures reported a mean change in neck pain of 2.0 on the numeric analogue scale, compared with 1.3 for those performing robotic procedures (p = 0.04). Conclusions: Real-time measurements of neck flexion during urologic surgery shows that greater duration and higher degree of neck flexion were associated with increased neck pain. Raising awareness about ergonomics in the operating room during residency will enable future generations of surgeons to make conscious decisions regarding their neck posture in surgery.

Importance of the cervical capsular joint cartilage geometry on head and facet joint kinematics assessed in a Finite element neck model

Finite element human neck models (NMs) aim to predict neck response and injury at the tissue level; however, contemporary models are most often assessed using global response such as head kinematics. Additionally, many NMs are developed from subject-specific imaging with limited soft tissue resolution in small structures such as the facet joints in the neck. Such details may be critical to enable NMs to predict tissue-level response. In the present study, the capsular joint cartilage (CJC) geometry in a contemporary NM was enhanced (M50-CJC) based on literature data. The M50-CJC was validated at the segment and full neck levels and assessed using relative facet joint kinematics (FJK), capsular ligament (CL) and intervertebral disc (IVD) strains, a relative vertebral rotation assessment (IV-NIC) and head kinematics in frontal and rear impact. The validation ratings at the segment level increased from 0.60 to 0.64, with improvements for modes of deformation associated with the facet joints, while no difference was noted at the head kinematic level. The improved CJC led to increased FJK rotation (188%) and IVD strain (152.2%,) attributed to the reduced facet joint gap. Further enhancements of the capsular joint representation or a link between the FJK and CL injury risk are recommended. Enhancements at the tissue level demonstrated a large effect on the IVD strain, but were not apparent in global metrics such as head kinematics. This study demonstrated that a biofidelic and detailed geometrical representation of the CJC contributes significantly to the predicted joint response, which is critical to investigate neck injury risk at the tissue level.

Biomechanical Analysis of Serious Neck Injuries Resulting from Judo.

To establish a basis for initial diagnosis and for proposing preventive measures for the serious neck injuries occasionally experienced by judo practitioners, the biomechanical mechanisms of these injuries were analyzed. Two male judo experts repeatedly threw an anthropomorphic test device (POLAR dummy) using three throwing techniques (Seoi-nage, Osoto-gari, and Ouchi-gari). The dummy’s kinematic data were captured using a high-speed digital camera, and the load and moment of the neck were measured with load cells. The neck injury criterion (Nij) and beam criterion were also calculated. In Seoi-nage, the anterior and parietal regions of the dummy’s head contacted the tatami (judo mat). Subsequently, most of the body weight was applied, with the neck experiencing the highest compression. However, in Osoto-gari and Ouchi-gari, the occipital region of the dummy’s head contacted the tatami. Significantly higher values of both Nij (median 0.68) and beam criterion (median 0.90) corresponding to a 34.7% to 37.1% risk of neck injury with an abbreviated injury scale score ≥2 were shown in Seoi-nage than in either Ouchi-gari or Osoto-gari. In judo, when thrown by the Seoi-nage technique, serious neck injuries can occur as a result of neck compression that occurs when the head contacts the ground.

Development of a detailed human neck finite element model and injury risk curves under lateral impact

Advanced neck finite element modeling and development of neck injury criteria are important for the design of optimal neck protection systems in automotive and other environments. They are also important in virtual tests. The objectives of the present study were to develop a detailed finite element model (FEM) of the human neck and couple it to the existing head model, validate the model with kinematic data from legacy human volunteer and human cadaver impact datasets, and derive lateral impact neck injury risk curves using survival analysis from the upper and lower neck forces and moments. The detailed model represented the anatomy of a young adult mid-size male. It included all the cervical and first thoracic vertebrae, intervening discs, upper and lower spinal ligaments, bilateral facet joints, and passive musculature. Material properties were obtained from literature. Frontal, oblique, and lateral impacts to the distal end of the model was applied based on human volunteer and human cadaver experimental data. Corridor and cross-correlation methods were used for validation. The CORrelation and Analysis (CORA) score was used for objective assessments. Forces and moments were obtained at the occipital condyles (OC) and T1, and parametric survival analysis was used to derive injury risk curves to define human neck injury tolerance to lateral impact. The Brier Score Metric (BSM) was used to determine the hierarchical sequence among the injury metrics. The CORA scores for the lateral, frontal, and oblique impact loading conditions were 0.80, 0.91, and 0.87, respectively, for human volunteer data, and the mean score was 0.7 for human cadaver lateral impacts. Injury risk curves along with ±95% confidence intervals are given for all the four biomechanical metrics. The OC shear force was the optimal metric based on the BSM. A force of 1.5 kN was associated with the 50% probability level of AIS3+ neck injury. As a first step, the presented risk curves serve as human tolerance criteria under lateral impact, hitherto not available in published literatures, and they can be used in virtual testing and advancing restraint systems for improving human safety.

Cervical spine range of motion and joint position sense in elite male cricketers: An observational study

OBJECTIVE: The aims of the current study were to (1) establish baseline data for cervical range of motion (CROM) and joint position sense (JPS) in elite male cricketers, (2) determine whether these players had differences when compared to healthy adults, and (3) establish a reference set of values for future investigations. MATERIALS AND METHODS: Design: Repeated measures, observational study. Participants: Thirty-one elite cricketers, aged 18–35 years. Setting: Cricket New South Wales at the Sydney Cricket Ground, Sydney, Australia. Outcome measures: Cervical rotation was measured with a CROM device and JPS using the joint position error (JPE) laser method with two protocols: repositioning to straight ahead and to 80% of maximum rotation. RESULTS: Mean right and left rotation were less than healthy normals by 6.5° (P 4.5° repositioning to straight ahead, which is 11% greater than the general population and 87% had JPE >4.5° when repositioning to 80% rotation. Postseason, deficits in CROM were unchanged. Fewer players (22%) had JPE >4.5° when repositioning to straight ahead however JPE when repositioning to 80% of rotation increased 1° for both directions (P CONCLUSIONS: Contrary to the authors' hypothesis, preliminary findings from this study demonstrated that elite male cricketers in this cohort had deficits in CROM and JPS, compared to normal healthy adults. This has clinical implications for the use of physical therapies targeting JPS and restoring CROM pre- and post-head and neck injury. Therapists should account for preexisting, baseline asymmetries in the range of motion and JPE in male cricketers. Further research needs to validate these findings across adolescent and female cricketers and explore the interaction between cervical spine parameters, cricket biomechanics, and head or neck injury risk.

Técnica quirúrgica para la corrección simultánea del prolapso de órganos pélvicos y la incontinencia urinaria recidivada mediante laparoscopia

IntroductionLaparoscopic sacral colpopexy (LSC) is the gold standard treatment for apical pelvic organ prolapse (POP). Artificial urinary sphincter (AUS) has a high success rate in treating recurrent stress urinary incontinence (SUI). ObjectiveTo describe the first simultaneous LSC and AUS implantation through a vesicovaginal approach to the bladder neck. Material and methodsOperation is performed through a transperitoneal approach. The rectovaginal space is created and the posterior mesh is fixed. The vesicovaginal and both laterovesical spaces are dissected. The vesicovaginal space is connected to both lateral spaces. This is main step of the procedure because it let us place the cuff around the bladder neck in a non-blind fashion. The anterior mesh is fixed to the vagina. The anterior side of the bladder neck is dissected and the cuff implanted. Both meshes are fixed to the promontory. Pressure-regulating balloon is inserted, the pump is placed in the labia majora and the components are connected. Peritoneum is closed. ResultsSurgical time was 180 minutes, bladder catheter was removed at 5th postoperative day, hospital stay was 5 days. The AUS was activated 6 weeks after surgery. No perioperative complications occurred. After 12 months the patient is pad-free and prolapse was objectively and subjectively cured. ConclusionsVesicovaginal dissection is a shared step in this technique of LSC and AUS implantation. This approach could minimize the risk of bladder neck injury. We propose this technique in selected cases of prolapse and recurrent SUI.

Restraint systems considering occupant diversity and pre-crash posture

Objective Use volunteer data and parametric finite element (FE) human body models to investigate how restraint systems can be designed to adapt to a diverse population and pre-crash posture changes induced by active safety features. Methods Four FE human models were generated by morphing the midsize male GHBMC simplified model into geometries representing a midsize male, midsize female, short obese female (BMI 40 kg/m2), and large obese male (BMI 40 kg/m2) based on statistical skeleton and body shape geometry models. Each human model was positioned in a generic vehicle driver environment using two occupant pre-crash postures based on volunteer test results including one resulting from 1-g abrupt braking events. Improved restraint designs were manually developed for each occupant model in a 56 km/h frontal crash condition by adding a knee airbag, adjusting the shoulder belt load limit, steering column force, and driver airbag properties (tethers, inflation, and vent size). The improved designs were then tested at both pre-crash postures. Injury risks for the head, neck, chest, and lower extremities were analyzed. Results Human size and shape dominated the occupant injury measures, while the pre-crash-braking induced posture had minimal effects. Some of the safety concerns observed for large occupants include head strike-through the airbag and a conflict between head and chest injuries, which were mitigated by a stiffer restraint system with properly-tuned driver airbag. Chest injuries were a prominent safety concern for female occupants, mitigated by a softer seatbelt and smaller airbag size near the chest. Obese occupants exhibited a higher likelihood of lower extremity injuries indicating a need for a knee airbag. A diverse set of improved restraint designs were effective in lowering injury risks, indicating that restraint adaptability is necessary for accounting for occupant diversity. Conclusions This study investigated the effects of occupant size and shape variability, posture, and restraint design on injury risk for high-speed frontal crashes. More forward initial postures due to active safety features may decrease head, neck, and lower extremity injury risk, but may also increase chest injury risk. Safety concerns observed for large occupants include head strike-through and a conflict between head and chest injuries. Obese occupants had higher knee-thigh-hip injury risk. New restraints that adapt to occupant size and body shape may improve crash safety for all occupants. Further investigation is needed to confirm and extend the findings of this study.

A comprehensive assessment of bus rollover crashes: integration of multibody dynamic and finite element simulation methods

Rollover crashes have the highest fatality rate and exhibit complex and unpredictable mechanisms in terms of vehicle-ground and vehicle-occupant interactions. The objective of this study is to evaluate the tilt table and modified dolly rollover (MDR) crash tests in terms of how these crash tests can represent those interactions and compare their results with two real-world rollover crashes. An application of combined dynamic and finite element (FE) simulations was presented to assess the cutaway bus rollover crash. First, the numerical models were validated against the experimental MDR test. Then, two real-world rollover crashes were simulated in PC-Crash to find the kinematics of the bus prior to the first vehicle-to-roof impact phase. Next, the impact phase of these real-world crashes was simulated using LS-DYNA and the results were compared with the two rollover crash tests. The FE simulations were conducted using a 2-point belted 50th Hybrid III FE model. The results of this study indicate that the common impact mechanism among these rollover scenarios was the impact between the bus’s roof corner (roof connection to the sidewall) and ground which caused lateral deformation patterns. Furthermore, unlike passenger cars where the vertical roof deformation can cause severe injuries in rollover crashes, the intrusion of the bus’s passenger compartment was not identified as a main source of injury. In addition, the highest head, neck, and chest injury risk were predicted during the MDR simulation where the ATD was partially ejected through the side window. Lastly, possible future works and limitations were explained.

Should airbags be deactivated for wheelchair-seated drivers?

Objective Field data have shown significant benefit from driver airbag for occupant protection in frontal crashes. However, vehicle modifiers almost always permanently deactivate airbags for wheelchair-seated drivers. The objective of this study was to conduct sled tests and computational simulations to answer whether driver airbags should be deactivated for drivers seated in wheelchairs. Methods Five sled tests were conducted under a 48-kph 20-g frontal crash pulse all with driver airbag. Seat-belt fit (good, poor, and unbelted), airbag deployment time (proper and late), and occupant size (midsize male and small female HIII ATDs) were varied in the tests. The 2006 Chrysler Town-and-Country minivan was selected as the nominal vehicle environment, and a surrogate wheelchair with a docking securement system was used for all sled tests. ATD injury measures for the head, neck, chest, and lower extremities were recorded in each test, and were used for validating a set of MADYMO models. Parametric studies with a total of 28 MADYMO simulations were then conducted to investigate the airbag effects on occupant injury risks with varied occupant size, belt fit, and impact angle (0, 15, and 30 deg). Results The sled tests showed potential safety concerns for wheelchair-seated drivers with a poor belt fit or without a belt. Specifically, the unbelted midsize male ATD sustained high femur forces and the small female ATD with poor belt fit sustained high chest deflections. The parametric simulations showed that airbag generally improved the protection for wheelchair-seated drivers. It is especially useful for unbelted wheelchair-seated drivers, and is also helpful for reducing the head and neck injury risks regardless of the belt condition, occupant size, and impact angle. Conclusions This is the first study using sled tests and computational simulations to investigate the effects of airbag deployment on injury risks of wheelchair-seated drivers. Overall, the results showed little basis for concern that the energy of deploying a driver airbag in today’s vehicles will cause serious-to-fatal injuries to drivers seated in wheelchairs. The results of this study therefore support the idea that driver airbags generally offer tangible safety benefits for a wide range of wheelchair-seated drivers in frontal crashes.

Relationship between head and neck injuries and helmet use in fatal motorcycle and moped crashes in Denmark

Abstract Motorcycle- and moped crashes are prevalent in motorised societies and carry a significant risk of serious injury. Whereas helmet use has reduced the frequency and severity of head injuries, the association between helmet use and neck injury risk is less clear. In the present retrospective study, we examined the relationship between helmet use and various types of head and neck injuries resulting from fatal motorcycle and moped crashes during a 20-year period. Eighty-three cases were included of whom 56 were analysed in detail based on their confirmed use/non-use of helmet. Intracranial haemorrhage was the most common finding, followed by CNS disruption and skull fracture. There was a significantly lower prevalence of skull vault fractures and epidural haemorrhage in the helmeted cases. Injuries to the brainstem and cervical spine fracture/dislocation were more common in the helmeted cases, although this was likely a function of higher speeds among motorcycle riders rather than an effect of helmet use per se. Further investigation of these findings require additional detailed information regarding the nature and severity of the crash, as well as helmet use and type, in order to assess non-confounded associations with the anatomical distribution, type and severity of observed head and neck injuries.

FEM-based Methodology for Crash Severity Estimation in Frontal Crash Scenarios

With the technological development of forward-looking sensors, researchers are exploring their use not only for advanced driver assistance systems but also to gain important pre-crash information. Based on this pre-crash information, if the occupant motion inside the vehicle structure can be predicted for the oncoming crash scenario, then an optimal restraint strategy can be planned before the crash. This paper introduces a two-step FEM simulation based methodology for predicting the occupant severity in head-on crash scenarios. In the first step, we simulate the vehicle level model with different impact positions and relative approach angles. The results of these simulations, linear velocities in the longitudinal and lateral direction and angular velocities (roll, pitch, and yaw) during in-crash phase are the loading conditions for next simulation step (occupant level). This step simulates the motion of the driver in different crash scenarios. In this paper, we investigate the head, neck, and chest injury risks from vehicle-to-vehicle crash both traveling at 50 kilometers per hour. Prediction of the head injury criterion, identifying the cases where additional deployment of side-airbags and discussion of injury criteria with contour plots are the main outcome of this paper.