A network-based response feature matrix as a brain injury metric

Conventional brain injury metrics are scalars that treat the whole head/brain as a single unit but do not characterize the distribution of brain responses. Here, we establish a network-based "response feature matrix" to characterize the magnitude and distribution of impact-induced brain strains. The network nodes and edges encode injury risks to the gray matter regions and their white matter interconnections, respectively. The utility of the metric is illustrated in injury prediction using three independent, real-world datasets: two reconstructed impact datasets from the National Football League (NFL) and Virginia Tech, respectively, and measured concussive and non-injury impacts from Stanford University. Injury predictions with leave-one-out cross-validation are conducted using the two reconstructed datasets separately, and then by combining all datasets into one. Using support vector machine, the network-based injury predictor consistently outperforms four baseline scalar metrics including peak maximum principal strain of the whole brain (MPS), peak linear/rotational acceleration, and peak rotational velocity across all five selected performance measures (e.g., maximized accuracy of 0.887 vs. 0.774 and 0.849 for MPS and rotational acceleration with corresponding positive predictive values of 0.938, 0.772, and 0.800, respectively, using the reconstructed NFL dataset). With sufficient training data, real-world injury prediction is similar to leave-one-out in-sample evaluation, suggesting the potential advantage of the network-based injury metric over conventional scalar metrics. The network-based response feature matrix significantly extends scalar metrics by sampling the brain strains more completely, which may serve as a useful framework potentially allowing for other applications such as characterizing injury patterns or facilitating targeted multi-scale modeling in the future.

Electric scooter injuries at Auckland City Hospital

AIM

Since the introduction of shared electric scooters to Auckland in October 2018, there have been multiple reports of injuries. We aim to examine the pattern of injuries sustained while riding electric scooters in patients presenting to hospital.

METHODS

We conducted a retrospective analysis of patients who presented to Auckland City Hospital Emergency Department (ED) between 15 October 2018 and 22 February 2019. Patients were firstly identified by ED staff and noted in a logbook, and secondly by searching the Trauma Registry database. Outcomes of interest were injuries, imaging, alcohol and helmet use, length of stay and interventions.

RESULTS

There were 180 patients identified. The median length of stay was 4.0 hours, interquartile range (IQR) 18.4 hours. One-third of patients were admitted or transferred. Common injuries were contusions, abrasions and lacerations (65.6%), fractures (41.7%) and head injuries (17.2%). One in five patients (22.2%) required an operation. Only three patients wore a helmet. Of all patients, 23.3% had consumed alcohol, and of those with head injuries; 41.9% had consumed alcohol.

CONCLUSION

This study highlights the significant number of electric scooter-related injuries, including severe head injuries. While the majority of presentations are categorised as minor trauma, these cases have placed additional demand on health system resources. This mode of transport would benefit from greater regulation, including a zero blood alcohol limit, night-time curfews, reduced speed limits and consideration of mandatory helmet use.

Shooting through windscreens: ballistic injury assessment using a surrogate head model-two case reports

A synthetic head model developed to reproduce military injuries was assessed in two different scenarios involving shooting through intermediate targets (a laminated vehicle windscreen in scenario 1 and a military helicopter windscreen in scenario 2) with 7.62 × 39-mm mild steel core (MSC) ammunition. The injury patterns resulting from the two scenarios were assessed by a military radiologist and a forensic pathologist with combat injury experience and found to be clinically realistic.

Adult moped-related injuries treated in U.S. emergency departments

Objective: Few studies have investigated U.S. emergency department (ED) moped-related injuries. Our objective was to determine the characteristics of moped crashes among adult riders and to identify associations between key variables.Methods: Data were obtained from the National Electronic Injury Surveillance System (NEISS) for 2002-2014. Descriptive and comparative analyses of the identified cases were performed.Results: Based on a probability sample of 2,453 cases, an estimated 108,229 U.S. adult moped-related ED visits occurred during the study period. Injuries increased 2.7-fold over time. Summer months and weekdays were the most common crash times. Three-fourths of injured riders were male, two-thirds were ages 23-59 years, and 77% were Caucasian. Among cases documented, one-half were helmeted, and almost two-thirds of crashes occurred at ≤20 mph. The predominant mechanism was a non-collision crash (60%). Skin-related and musculoskeletal diagnoses were most common. Almost one-fifth of patients were admitted or transferred. Regression analyses showed that males were less likely than females to be in crashes with multiple riders, and more likely to have used alcohol/drugs and to be in a crash with another motor vehicle (MVC). Older riders (≥40 years) were more likely than those younger to have used alcohol/drugs and to suffer torso injuries, and less likely to be in an MVC. As compared to other crash mechanisms, MVCs were more likely to involve injuries to the head/neck/face and torso. The likelihood of being admitted/transferred was higher for males, with increasing age, and for collision-related crashes. The higher likelihood of being admitted/transferred was also characterized by alcohol/drug use, by lower limb and torso injuries, and almost 8 times more likely for riders with serious head injuries.Conclusions: Moped injuries increased in all adult age groups during the study period. However, there were significant differences in contributing factors, crash mechanism, and outcomes by sex, race, and age. These findings suggest the need for targeted injury prevention interventions.

Underutilized strategies in traffic safety: Results of a nationally representative survey

Objective: Numerous strategies proven to be effective in reducing crash fatalities have been underutilized in the United States, including sobriety checkpoints; automated enforcement; lower blood alcohol concentration (BAC) limits; primary enforcement of safety belt and motorcycle helmet use laws; alcohol ignition interlock installations; drugged driving screening; lowered residential speed limits; and roundabout installations. If these strategies are implemented widely in every state, traffic fatalities could be reduced by at least 50%. A barrier to implementation is the perception by officials that the public is against them. The purpose of this study was to determine which of these underutilized measures would be favorable to the American public given that they are educated on the research of their effectiveness.Methods: A representative survey of 2,000 U.S. drivers was conducted in October 2018 with 30 questions about these underutilized strategies using the National Opinion Research Center's (NORC) AmeriSpeak® survey instrument. Our objective was to gauge the public's opinion of these strategies when they are aware of the research on their effectiveness.Results: Respondents were given a summary of the research on the effectiveness of these strategies and then asked whether they were in favor of them in their communities; 64.7% of the respondents were in favor of conducting sobriety checkpoints at least monthly; 68.2% were in favor of police using passive alcohol sensors at sobriety checkpoints; 60.3% of respondents were in favor of using speed and red light cameras for automated enforcement; 70.1% were in favor of a law that required all cars to have seat belt reminders that continuously chime until the seat belt is buckled, including for rear seat passengers; and 62.5% were in favor of raising the fine in their state for not using a seat belt from $25 to $100. Other results indicated public support for these strategies.Conclusions: The results indicate that when drivers in the United States are given facts about certain strategies to reduce crash fatalities, the majority are in favor of the underutilized strategies. This information could be useful to legislators and highway safety officials in their decisions to implement these strategies.

A six-year review of patients admitted to hospital with injuries related to quad bike use

AIM

To describe quad bike injury-related hospitalisations in the Midland region over a six-year period.

METHOD

A retrospective review of anonymised, prospectively-collected trauma registry data from 1 July 2012 to 30 June 2018 was undertaken. Cases include patients hospitalised with quad bike-related injuries. Non-major injuries are included to provide a clearer picture of the trauma burden.

RESULTS

Three hundred and forty-six injuries resulted in hospitalisation with 70.2% of events occurring on a farm. Males outnumbered females 3.7:1. Forty-six children (<16 years) were hospitalised, of which 23 were injured on-farm and seven on a road. Over six years there was an annual average increase of 7.3% for all events occurring on a farm, 2.6% for injuries occurring during a farming activity and 4.7% for off-farm recreational injuries.

CONCLUSION

Despite continued public debate and education on the safe use of quad bikes, injuries severe enough to require hospitalisation continue to occur. Children continue to be injured, both as riders and passengers. Ageing farmers are a developing area for concern. While workplace safety garners most of the safety attention, two other areas also deserve injury prevention consideration; injuries that occur on-farm but not during farming activities and those occurring off-farm to recreational riders.

[Equestrian related injuries and pathologies]

Equestrian sports are widely practiced in Switzerland as hobbies. Horses are imposing and unpredictable. As a result, traumatisms associated with horseback riding are common and cause serious injuries. Cranial traumatisms are among the most frequently encountered injuries and are associated with high rates of hospitalization and mortality. Helmet use decreases the severity of intracranial lesions. Close contact with horses can lead to the development of infectious diseases and respiratory allergies. Although infrequent in Europe, these infections occur sporadically and should be known by general practitioners. Finally, horse's allergens sensitization is frequent in allergic patients with or without direct contact with horses.

[Analysis of the frequency of polytraumatized patients in motorcycle accidents in the pediatric publication attended in the Pediatric Hospital of Sinaloa between the years 2015 and 2017]

OBJECTIVES

Determine the frequency of polytraumatized pediatric patients involved in motorcycle accidents treated at the Pediatric Hospital of Sinaloa between 2015 and 2017, as well as to determine the frequency of traumatic brain injuries, thoracic, abdominal, limb injuries, days of hospital stay and mortality.

MATERIAL AND METHODS

The selected population were patients under 18 years of age who were involved in motorcycle accidents treated at the Pediatric Hospital of Sinaloa in a period between January 1st, 2015 and December 31, 2017.

RESULTS

The most affected gender was the male with the most frequent age of 14 years, accidents occurred more frequently on Fridays and Saturdays at night. July was the month with the highest frequency of accidents. The number of accidents increased every year. Most of the injured were passengers, 98.4% did not use safety equipment, the most frequent injury was head injury, followed by injuries in lower extremities, upper chest trauma and less frequent abdominal traumatism.

DISCUSSION

There is a progressive increase in motorcycle accidents where the pediatric population is involved, the use of helmet is almost zero, most of the patients presented with head trauma, this study serves to see the current situation, as well as being the basis for Subsequent studies and conduct more campaigns for the prevention of motorcycle accidents and encourage the use of helmet in pediatric patients.

Development of a subject-specific guide system for Low-Intensity Focused Ultrasound (LIFU) brain stimulation

Low-Intensity Focused Ultrasound (LIFU) has recently been considered as a promising neuromodulation technique because it can noninvasively stimulate the brain with a high spatial resolution. As spatial resolution is improved, there is a growing demand for developing more accurate and convenient guide systems. Therefore, in the present study, we have developed and prototyped a 3D printed wearable subject-specific helmet for LIFU stimulation that is guaranteed to be accurate. The spatial relationship between the target position and the full-width at half-maximum (FWHM) of acoustic pressure of the transducer, i.e. focal volume, was compared using the conventional image-guided navigation system. According to the distribution of positional errors, the target position was located well within the focal volume.

Local All-Age Bicycle Helmet Ordinances in the United States: A Review and Analysis

Bicycle helmets protect against head injury. Mandatory helmet laws likely increase their use. Although 21 states and Washington, DC have mandatory helmet laws for youth (variously defined) bicyclists, no U.S. state has a mandatory helmet law that applies to all ages; however, some localities have all-age helmet laws for bicyclists. This study abstracted local helmet laws applicable to all-ages to examine their elements.

Validation of a three-dimensional visual target acquisition system for evaluating the performance effects of head supported mass

Night vision goggles (NVGs) enable aircrew to complete missions in the cover of night, but dramatically increase and alter the distribution of mass borne by the head. Our novel approach to visual target acquisition, based on Fitts' Law, was used to assess differences across three different performance metrics between low (L) and high (H) head supported mass (HSM) conditions. Fifteen healthy male participants completed time-optimal and reciprocal visual target acquisitions between target pairs arranged in four different movement trajectories. A significant interaction effect was found and subsequent post hoc analysis revealed that participants required more time to acquire the 20 mm target in the H-HSM condition. In the H-HSM condition participants had a higher error index during target acquisition and required more time to move off the target. Our approach demonstrates great promise in distinguishing performance decrements associated with the use of helmeted systems that include NVGs.

Gender Differences in Dry-EEG Manifestations During Acute and Insidious Normobaric Hypoxia

INTRODUCTION: Prior research suggests there may be gender differences with regards to hypoxia resilience. Our study was designed to determine whether there were differences between genders in neuronal electrical activity at simulated altitude and whether those changes correlated with cognitive and aviation performance decrements.METHODS: There were 60 student Naval Aviators or Flight Officers who completed this study (30 women, 30 men). Participants were exposed to increasing levels of normobaric hypoxia and monitored with dry EEG while flying a fixed-base flight simulation. Gender differences in brainwave frequency power were quantified using MATLAB. Changes in flight and cognitive performance were analyzed via simulation tasks and with a cognitive test validated under hypoxia.RESULTS: Significant decreases in theta and gamma frequency power occurred for women compared to men with insidious hypoxic exposures to 20K, with an average frequency power decrease for women of 19.4% compared to 9.3% for men in theta, and a 42.2% decrease in gamma for women compared to 21.7% for men. Beta frequency power correlated highest between genders, with an average correlation coefficient of r = 0.95 across seven channels.DISCUSSION: Results of this study suggest there is identifiable brain wave suppression for both men and women with hypoxic exposure and, moreover, there are significant differences in this suppression between genders. Beta frequency power was most sensitive for both genders and highly correlative compared to other brainwave frequencies. The implications of these findings are important considerations for next-generation aviation helmets, which may employ this technology as an early warning mechanism.Rice GM, Snider D, Drollinger S, Greil C, Bogni F, Phillips J, Raj A, Marco K, Linnville S. Gender differences in dry-EEG manifestations during acute and insidious normobaric hypoxia. Aerosp Med Hum Perform. 2019; 90(4):369-377.

Motorized scooter injuries in the era of scooter-shares: A review of the national electronic surveillance system

INTRODUCTION

There has been a spike in recent news regarding motorized scooter injuries due to the expansion of scooter sharing companies. Given the paucity of literature on this topic, the purpose of our study was to describe and quantify emergency department encounters associated with motorized scooter related injuries.

METHODS

The National Electronic Injury Surveillance System (NEISS) was queried for motorized scooter related injuries from 2013 to 2017. Patient demographics, diagnosis, injury location, narrative description of incident, and disposition data were collected from emergency department encounters.

RESULTS

There were an estimated 32,400 motorized scooter injuries from 2013 to 2017. The estimated incidence did not change significantly over time with 1.9 cases per 100,000 in 2013 and 2.6 cases per 100,000 in 2017. A 77.0% increase in scooter injuries was noted for millennials from 2016 to 2017. Head injuries were the most common body area injured (27.6%). Fractures or dislocations (25.9%) were the most common diagnosis. The most common site of fracture was the wrist and lower arm (35.4%). There were no deaths. Major orthopaedic injury and concussion were the strongest independent predictors of hospital admission.

CONCLUSIONS

Head injuries were the most commonly injured body part, while fractures or dislocations were the most common diagnosis. These results highlight the importance of using protective equipment while riding motorized scooters, and lay a foundation for future policies requiring helmet use.

Evaluation of a novel bicycle helmet concept in oblique impact testing

BACKGROUND

A novel bicycle helmet concept has been developed to mitigate rotational head acceleration, which is a predominant mechanism of traumatic brain injury (TBI). This WAVECEL concept employs a collapsible cellular structure that is recessed within the helmet to provide a rotational suspension. This cellular concept differs from other bicycle helmet technologies for mitigation of rotational head acceleration, such as the commercially available Multi-Directional Impact Protection System (MIPS) technology which employs a slip liner to permit sliding between the helmet and the head during impact. This study quantified the efficacy of both, the WAVECEL cellular concept, and a MIPS helmet, in direct comparison to a traditional bicycle helmet made of rigid expanded polystyrene (EPS).

METHODS

Three bicycle helmet types were subjected to oblique impacts in guided vertical drop tests onto an angled anvil: traditional EPS helmets (CONTROL group); helmets with a MIPS slip liner (SLIP group); and helmets with a WAVECEL cellular structure (CELL group). Helmet performance was evaluated using 4.8 m/s impacts onto anvils angled at 30°, 45°, and 60° from the horizontal plane. In addition, helmet performance was tested at a faster speed of 6.2 m/s onto the 45° anvil. Five helmets were tested under each of the four impact conditions for each of the three groups, requiring a total of 60 helmets. Headform kinematics were acquired and used to calculate an injury risk criterion for Abbreviated Injury Score (AIS) 2 brain injury.

RESULTS

Linear acceleration of the headform remained below 90 g and was not associated with the risk of skull fracture in any impact scenario and helmet type. Headform rotational acceleration in the CONTROL group was highest for 6.2 m/s impacts onto the 45° anvil (7.2 ± 0.6 krad/s²). In this impact scenario, SLIP helmets and CELL helmets reduced rotational acceleration by 22% (p = 0003) and 73% (p < 0.001), respectively, compared to CONTROL helmets. The CONTROL group had the highest AIS 2 brain injury risk of 59 ± 8% for 6.2 m/s impacts onto the 45° anvil. In this impact scenario, SLIP helmets and CELL helmets reduced the AIS 2 brain injury risk to 34.2% (p = 0.001) and 1.2% (p < 0.001), respectively, compared to CONTROL helmets.

DISCUSSION

Results of this study are limited to a narrow range of impact conditions, but demonstrated the potential that rotational acceleration and the associated brain injury risk can be significantly reduced by the cellular WAVECEL concept or a MIPS slip liner. Results obtained under specific impact angles and impact velocities indicated performance differences between these mechanisms. These differences emphasize the need for continued research and development efforts toward helmet technologies that further improve protection from brain injury over a wide range a realistic impact parameters.

Bicycle helmet wearing is associated with closer overtaking by drivers: A response to Olivier and Walter, 2013

There is a body of research on how driver behaviour might change in response to bicyclists' appearance. In 2007, Walker published a study suggesting motorists drove closer on average when passing a bicyclist if the rider wore a helmet, potentially increasing the risk of a collision. Olivier and Walter re-analysed the same data in 2013 and claimed helmet wearing was not associated with close vehicle passing. Here we show how Olivier and Walter's analysis addressed a subtly, but importantly, different question than Walker's. Their conclusion was based on omitting information about variability in driver behaviour and instead dividing overtakes into two binary categories of 'close' and 'not close'; we demonstrate that they did not justify or address the implications of this choice, did not have sufficient statistical power for their approach, and moreover show that slightly adjusting their definition of 'close' would reverse their conclusions. We then present a new analysis of the original dataset, measuring directly the extent to which drivers changed their behaviour in response to helmet wearing. This analysis confirms that drivers did, overall, get closer when the rider wore a helmet. The distribution of overtaking events shifted just over one-fifth of a standard deviation closer to the rider - a potentially important behaviour if, as theoretical frameworks suggest, near-misses and collisions lie on a continuum. The paper ends by considering wider issues surrounding this topic and suggests public health research might be best served by shifting focus to risk elimination rather than harm mitigation.

Identifying high-risk built environments for severe bicycling injuries

INTRODUCTION

This study is aimed at filling part of the knowledge gap on bicycling safety in the built environment by addressing two questions. First, are built environment features and bicyclist injury severity correlated; and if so, what built environment factors most significantly relate to severe bicyclist injuries? Second, are the identified associations varied substantially among cities with different levels of bicycling and different built environments?

METHODS

The generalized ordered logit model is employed to examine the relationship between built environment features and bicyclist injury severity.

RESULTS

Bicyclist injury severity is coded into four types, including no injury (NI), possible injury (PI), evident injury (EI), and severe injury and fatality (SIF). The findings include: (a) higher percentages of residential land and green space, and office or mixed use land are correlated with lower probabilities of EI and SIF; (b) land use mixture is negatively correlated with EI and SIF; (c) steep slopes are positively associated with bicyclist injury severity; (d) in areas with more transit routes, bicyclist injury is less likely to be severe; (e) a higher speed limit is more likely to correlate with SIF; and (f) wearing a helmet is negatively associated with SIF, but positively related to PI and EI. Practical applications: To improve bicycle safety, urban planners and policymakers should encourage mixed land use, promote dense street networks, place new bike lanes in residential neighborhoods and green spaces, and office districts, while avoiding steep slopes. To promote bicycling, a process of evaluating the risk of bicyclists involving severe injuries in the local environment should be implemented before encouraging bicycle activities.

Assessing the level of radiation experienced by anesthesiologists during transfemoral Transcatheter Aortic Valve Implantation and protection by a lead cap

OBJECTIVE

Transfemoral Transcatheter Aortic Valve Implantation (TAVI) has become a standard therapy for patients with aortic valve stenosis. Fluoroscopic imaging is essential for TAVI with the anesthesiologist's workplace close to patient's head side. While the use of lead-caps has been shown to be useful for interventional cardiologists, data are lacking for anesthesiologists.

METHODS

A protective cap with a 0.35 lead-equivalent was worn on 15 working days by one anesthesiologist. Six detectors (three outside, three inside) were analyzed to determine the reduction of radiation. Literature search was conducted between April and October 2018.

RESULTS

In the observational period, 32 TAVI procedures were conducted. A maximum radiation dose of 0.55 mSv was detected by the dosimeters at the outside of the cap. The dosimeters inside the cap, in contrast, displayed a constant radiation dose of 0.08 mSv.

CONCLUSION

The anesthesiologist's head is exposed to significant radiation during TAVI and it can be protected by wearing a lead-cap.

Injuries Associated With Standing Electric Scooter Use

IMPORTANCE

Since September 2017, standing electric scooters have proliferated rapidly as an inexpensive, easy mode of transportation. Although there are regulations for safe riding established by both electric scooter companies and local governments, public common use practices and the incidence and types of injuries associated with these standing electric scooters are unknown.

OBJECTIVE

To characterize injuries associated with standing electric scooter use, the clinical outcomes of injured patients, and common use practices in the first US metropolitan area to experience adoption of this technology.

DESIGN, SETTING, AND PARTICIPANTS

This study of a case series used retrospective cohort medical record review of all patients presenting with injuries associated with standing electric scooter use between September 1, 2017, and August 31, 2018, at 2 urban emergency departments associated with an academic medical center in Southern California. All electric scooter riders at selected public intersections in the community surrounding the 2 hospitals were also observed during a 7-hour observation period in September 2018.

MAIN OUTCOMES AND MEASURES

Incidence and characteristics of injuries and observation of riders' common use practices.

RESULTS

Two hundred forty-nine patients (145 [58.2%] male; mean [SD] age, 33.7 [15.3] years) presented to the emergency department with injuries associated with standing electric scooter use during the study period. Two hundred twenty-eight (91.6%) were injured as riders and 21 (8.4%) as nonriders. Twenty-seven patients were younger than 18 years (10.8%). Ten riders (4.4%) were documented as having worn a helmet, and 12 patients (4.8%) had either a blood alcohol level greater than 0.05% or were perceived to be intoxicated by a physician. Frequent injuries included fractures (79 [31.7%]), head injury (100 [40.2%]), and contusions, sprains, and lacerations without fracture or head injury (69 [27.7%]). The majority of patients (234 [94.0%]) were discharged home from the emergency department; of the 15 admitted patients, 2 had severe injuries and were admitted to the intensive care unit. Among 193 observed electric scooter riders in the local community in September 2018, 182 (94.3%) were not wearing a helmet.

CONCLUSIONS AND RELEVANCE

Injuries associated with standing electric scooter use are a new phenomenon and vary in severity. In this study, helmet use was low and a significant subset of injuries occurred in patients younger than 18 years, the minimum age permitted by private scooter company regulations. These findings may inform public policy regarding standing electric scooter use.

The potential of vehicle and road infrastructure interventions in fatal bicyclist accidents on Swedish roads-What can in-depth studies tell us?

Objective: The objective of this article is to describe the characteristics of fatal crashes with bicyclists on Swedish roads in rural and urban areas and to investigate the potential of bicycle helmets and different vehicle and road infrastructure interventions to prevent them. The study has a comprehensive approach to provide road authorities and vehicle manufacturers with recommendations for future priorities. Methods: The Swedish Transport Administration's (STA) in-depth database of fatal crashes was used for case-by-case analysis of fatal cycling accidents (2006-2016) on rural (n = 82) and urban (n = 102) roads. The database consists of information from the police, medical journals, autopsy reports, accident analyses performed by STA, and witness statements. The potential of helmet use and various vehicle and road infrastructure safety interventions was determined retrospectively for each case by analyzing the chain of events leading to the fatality. The potential of vehicle safety countermeasures was analyzed based on prognoses on their implementation rates in the Swedish vehicle fleet. Results: The most common accident scenario on rural roads was that the bicyclist was struck while cycling along the side of the road. On urban roads, the majority of accidents occurred in intersections. Most accidents involved a passenger car, but heavy trucks were also common, especially in urban areas. Most accidents occurred in daylight conditions (73%). Almost half (46%) of nonhelmeted bicyclists would have survived with a helmet. It was assessed that nearly 60% of the fatal accidents could be addressed by advanced vehicle safety technologies, especially autonomous emergency braking with the ability to detect bicyclists. With regard to interventions in the road infrastructure, separated paths for bicyclists and bicycle crossings with speed calming measures were found to have the greatest safety potential. Results indicated that 91% of fatally injured bicyclists could potentially be saved with known techniques. However, it will take a long time for such technologies to be widespread. Conclusions: The majority of fatally injured bicyclists studied could potentially be saved with known techniques. A speedy implementation of important vehicle safety systems is recommended. A fast introduction of effective interventions in the road infrastructure is also necessary, preferably with a plan for prioritization.

Comparison of head impact exposure in practice drills among multiple youth football teams

Objective

Limiting contact in football practice can reduce the number of head impacts a player receives, but further research is needed to inform the modification of optimal drills that mitigate head impact exposure (HIE) while the player develops the skills needed to safely play the game. This study aimed to compare HIE in practice drills among 6 youth football teams and to evaluate the effect of a team on HIE.

Methods

On-field head impact data were collected from athletes (ages 10–13 years) playing on 6 local youth football teams (teams A–F) during all practices using the Head Impact Telemetry System. Video was recorded and analyzed to verify and assign impacts to a specific drill. Drills were identified as follows: dummy/sled tackling, half install, install, install walk through, multiplayer tackle, Oklahoma, one-on-one, open field tackling, other, passing, position skill work, scrimmage, special teams, tackling drill stations, and technique. HIE was quantified in terms of impacts per player per minute (ppm) and peak linear and rotational head acceleration. Generalized linear models were used to assess differences in head impact magnitude and frequency among drills as well as among teams within the most common drills.

Results

Among 67 athlete-seasons, a total of 14,718 impacts during contact practices were collected and evaluated in this study. Among all 6 teams, the mean linear (p < 0.0001) and rotational (p < 0.0001) acceleration varied significantly among all drills. Open field tackling had significantly (p < 0.001) higher mean linear acceleration than all other drills. Multiplayer tackle had the highest mean impact rate (0.35 ppm). Significant variations in linear acceleration and impact rate were observed among teams within specific drills. Team A had the highest mean linear acceleration in install, one-on-one, and open field tackling and the highest mean impact rate in Oklahoma and position skill work. Although team A spent the greatest proportion of their practice on minimal- or no-player versus player contact drills (27%) compared to other teams, they had the highest median (20.2g) and 95th percentile (56.4g) linear acceleration in practice.

Conclusions

Full-speed tackling and blocking drills resulted in the highest HIE. Reducing time spent on contact drills relative to minimal or no contact drills may not lower overall HIE. Instead, interventions such as reducing the speed of players engaged in contact, correcting tackling technique, and progressing to contact may reduce HIE more effectively.

Bicycle helmet use and facial injuries

Data sourcesPubMed/Medline, Google Scholar and Cochrane Library databasesStudy selectionTwo reviewers independently selected studies. Observational studies involving patients >16 years comparing facial injuries in those wearing and not wearing cycle helmets were included. Studies were excluded if they examined the effects of helmet legislation, reported facial injuries with other injuries, compared different types of helmet or were wholly paediatric studies.Data extraction and synthesisSelection, reporting, attrition and detection bias of studies were assessed. Data were extracted on the incidence of all facial injuries reported in helmet users and non-helmet users by two reviewers independently. Odds ratios (OR) were extracted for facial injuries and facial fractures and meta-analysis conducted.ResultsThis review suggests that bicycle helmets may offer a protective benefit against facial fractures. However, it is noted that previous analyses have shown that this protection is not uniform across the face and that the upper and middle face may be protected.ConclusionsThis review suggests that bicycle helmets may offer a protective benefit against facial fractures. However, it is noted that previous analyses have shown that this protection is not uniform across the face and that the upper and middle face may be protected.

Injury prevalence and safety habits of boda boda drivers in Moshi, Tanzania: A mixed methods study

BACKGROUND

Traffic crashes are a major cause of global morbidity and mortality disproportionately affecting low- and middle-income countries (LMICs). Motorcycle taxi (boda boda) drivers are particularly vulnerable because they are exposed to traffic risks with limited safety equipment. This study aims to characterize injury prevalence and safety habits among boda boda drivers, as well as ways to improve road traffic safety in LMICs.

METHODS

A cross-sectional mixed methods study was conducted with 300 boda boda drivers between 24 March and 3 April 2014 in urban Moshi, Tanzania. A convenience sample of participants was drawn from 25 of 58 registered boda boda stands and 2 of 31 unregistered stands. Data were analyzed using R, and content thematic analysis was performed and agreed upon by three investigators. Logistic regression models were used to evaluate the association between boda boda characteristics and injury risk.

RESULTS

In total, 300 drivers participated, of whom 148 (49.3%) had experienced a crash during their lifetime, and 114 (77.0%) sustained at least one injury. Only 27 of those injured (23.4%) were hospitalized. Of all participants, 220 (73.3%) reported consistent helmet usage, despite 285 participants (95.0%) agreeing that helmet usage reduces injury severity. From the 280 helmets observed, 231 (82.5%) were either damaged or fit improperly. Having a cracked helmet was associated with higher risk of being involved in a traffic crash. Owning a helmet with a proper fit was associated with reduced risk for a traffic crash (OR = 0.06) and road traffic injuries (OR = 0.07). A thematic analysis of boda boda drivers' suggestions to increase road safety identified four intervention areas: 1) roadway infrastructure and traffic regulation, 2) road user attitudes and safe driving behaviors, 3) education and training, and 4) law enforcement.

CONCLUSION

Our study demonstrates boda boda drivers' safety behaviors and identifies four intervention areas that can be leveraged to increase overall road traffic safety. Unfortunately, while boda boda drivers are aware of ways to improve safety, adherence to safety habits remains low. Successful multi-sectoral interventions are needed to improve road safety for boda boda drivers in Tanzania.

Cranial orthosis after cochlear implantation in an infant: Helmet modifications

We present an infant with bilateral sensorineural hearing loss caused by bacterial meningitis, and moderate/severe plagiocephaly requiring simultaneous treatment of cochlear implantation for hearing loss and cranial orthosis for plagiocephaly. A helmet modification was created, so that the infant was able to be treated for his plagiocephaly while bilateral cochlear implants were in place, bringing attention to serve needs of those patients requiring cochlear implant and cranial orthosis concurrently. While this case was the first time such a modification was required, which was due to the young age at implantation, the occurrence of the concurrent need may increase as we continue to push the boundaries of early implantation.

Do Infield Softball Masks Effectively Reduce Facial Fracture Risk?

Infield softball masks are intended to reduce facial fracture risk, but are rarely worn. The objective of this study was to evaluate the effectiveness of infield masks’ ability to attenuate facial fracture risk over a range of designs and materials. To simulate batted ball impacts, a customized pitching machine was used to propel softballs at 24.6 ± 0.51 m/s. The balls impacted locations centered over the maxilla and zygoma bones of a FOCUS headform. The FOCUS headform was attached to a 50th percentile Hybrid III neck and secured to a slider table. Facial fracture risk of each facial bone was compared between masks and impact locations using peak resultant forces. Analysis of these data showed that the mask material and the distance between the mask and the impacted facial bone were key factors in determining a mask’s performance. The effectiveness of masks varied. It was found that a metal mask with a separation distance ≥ 35 mm away from the maxilla and ≥ 25 mm away from the zygoma best reduced facial fracture risk for these test configurations. Plastic masks performed worse because they excessively deformed allowing ball contact with the face. This study assesses various mask designs for their ability to reduce facial fracture and suggests design recommendations based on the impact configurations tested.

Effectiveness of wearing a bicycle helmet for impacts against the front of a vehicle and the road surface

OBJECTIVE

To assess the effect of wearing a bicycle helmet using an adult headform in terms of the head injury criterion (HIC) when the frontal and lateral parts of the helmet impact a vehicle body and also when the frontal part of the helmet impacts the road surface.

METHODS

The adult headform was made to impact the hood, windscreen, roof top, and roof side rail of a vehicle body at an impact velocity of 35 km/h, which is a common head-to-vehicle impact velocity in real-world cyclist-vehicle collisions, in which the vehicle impacts the cyclist at 40 km/h. For the road surface impact experiments, we set a drop height of 1.5 m (impact velocity of 20 km/h).

RESULTS

Helmet usage helped to reduce the HIC when the frontal and lateral parts of the helmet impacted vehicle parts other than the hood. The HIC reduction for the frontal impact was greater than that for the lateral impact. Moreover, the higher the stiffness index of the vehicle structure, the greater was the HIC reduction. However, helmet usage was ineffective for reducing skull fracture risk (HIC 2558) when the lateral part of the helmet impacted stiffer parts of the vehicle, such as the roof side rail close to the B-pillar. Helmet usage helped to reduce the HIC by 91% when the frontal part of the helmet impacted the road surface.

CONCLUSIONS

Wearing a helmet reduces skull fracture risk when the frontal and lateral parts of the helmet impact vehicle parts (excluding the hood) at 35 km/h and the road surface at 20 km/h. However, when the lateral part of the helmet impacts the B-pillar, the helmet cannot effectively reduce the skull fracture risk at these real-world velocities.

Comparison of Head Impact Exposure Between Concussed Football Athletes and Matched Controls: Evidence for a Possible Second Mechanism of Sport-Related Concussion

Studies of football athletes have implicated repetitive head impact exposure in the onset of cognitive and brain structural changes, even in the absence of diagnosed concussion. Those studies imply accumulating damage from successive head impacts reduces tolerance and increases risk for concussion. Support for this premise is that biomechanics of head impacts resulting in concussion are often not remarkable when compared to impacts sustained by athletes without diagnosed concussion. Accordingly, this analysis quantified repetitive head impact exposure in a cohort of 50 concussed NCAA Division I FBS college football athletes compared to controls that were matched for team and position group. The analysis quantified the number of head impacts and risk weighted exposure both on the day of injury and for the season to the date of injury. 43% of concussed athletes had the most severe head impact exposure on the day of injury compared to their matched control group and 46% of concussed athletes had the most severe head impact exposure for the season to the date of injury compared to their matched control group. When accounting for date of injury or season to date of injury, 72% of all concussed athletes had the most or second most severe head impact exposure compared to their matched control group. These trends associating cumulative head impact exposure with concussion onset were stronger for athletes that participated in a greater number of contact activities. For example, 77% of athletes that participated in ten or more days of contact activities had greater head impact exposure than their matched control group. This unique analysis provided further evidence for the role of repetitive head impact exposure as a predisposing factor for the onset of concussion. The clinical implication of these findings supports contemporary trends of limiting head impact exposure for college football athletes during practice activities in an effort to also reduce risk of concussive injury.

Characteristics and risk factors of bike-related accidents: Preliminary analysis

BACKGROUND

The growing popularity of cycling not only enhances self-efficacy, physical well-being and improves quality of life, but it also leads to the increasing number of bike-related injuries.

OBJECTIVES

The aim of this study was to characterize the population of cyclists in Poland, assess the occurrence of safety behaviors among them and to precise the risk factors for bike accidents. Additionally, we analyzed bike-related injuries.

MATERIAL AND METHODS

The survey was based on a 39-item questionnaire created for this study. We collected data concerning the demographical status of respondents, their cycling preferences, attitude toward safety behaviors during cycling, and the characteristics of bike-related injuries. Our research covered 729 people who declared themselves as cyclists (302 women - average age: 31.5 ±10.3 years; 427 men - average age: 32.6 ±10.7 years).

RESULTS

In the study, 71.3% of the interviewees declared that they did not always wear helmets. Women more often than men claimed that they did not always use head protection (p < 0.001). Among 729 people, 277 suffered from bike-related injuries. In this group, we noted 870 accidents that resulted in 1,671 different injuries. In our study, wearing helmets did not influence the region of trauma nor its type (p < 0.05). We noted 811 injuries of the upper extremities and 541 of the lower extremities.

CONCLUSIONS

Young men constitute the main group of cyclists in Poland. The risk factors for bike-related accidents in our study proved to be: educational level (secondary education and incomplete higher education), number of children (having at least 3 children), frequency of using a bike (the more often, the more injuries), type of bike used (mountain bikes and fold-up bikes), and frequency of using a helmet (using helmets was correlated with a higher rate of injuries). The upper and lower extremities were the most common location of injuries.

Bone Conduction as a Viable Alternative to Current Communications Systems in Fighter Cockpits

INTRODUCTION

Effective voice communication is essential when operating aircraft. Because of the loud operating environment in fighter cockpits, it has been a challenge to provide effective communication while simultaneously protecting the hearing sense. The objective of this study was to determine the feasibility of using bone conducting transducers (BCT) in place of legacy communications systems in fighter cockpits.

METHODS

A military flight helmet was modified and outfitted with BCT and air-conducting speakers. BCT were independently tested against air-conducting speakers using a clinical audiometer under three conditions: without earplugs, with earplugs, and with earplugs in the presence of 100-dB broad-spectrum noise. Three test subjects were given an audiological examination using tones of varying intensity ranging from 100 Hz to 8000 Hz. The lowest hearable intensity indicated by button press was recorded for each frequency.

RESULTS

In the presence of 100-dB ambient noise, bone conducting transducers performed better than air-conducting speakers at all frequencies. Hearability of BCT by audiogram was, on average, 10-20% lower intensity (dB) than air-conducting speakers.

DISCUSSION

Currently, USAF pilots wear two layers of hearing protection; i.e., the helmet's integrated earcup and some form of ear plug (e.g., foam earplug or custom-molded earbud). Our results suggest that bone conducting audio transducers may be better for layered hearing protection than air-conducting speakers when used with foam earplugs. Given the cost, complexity, and non-interoperability of custom-molded earphones, helmet-integrated bone conducting transducers and foam earplugs may be a better option for sustained airborne operations.Bradke BS, White Z, Poston J. Bone conduction as a viable alternative to current communications systems in fighter cockpits. Aerosp Med Hum Perform. 2018; 89(10):927-930.

Applying the health action process approach to bicycle helmet use and evaluating a social marketing campaign

BACKGROUND

Bicycle injuries are of concern in Canada. Since helmet use was mandated in 1996 in the province of British Columbia, Canada, use has increased and head injuries have decreased. Despite the law, many cyclists do not wear a helmet. Health action process approach (HAPA) model explains intention and behaviour with self-efficacy, risk perception, outcome expectancies and planning constructs. The present study examines the impact of a social marketing campaign on HAPA constructs in the context of bicycle helmet use.

METHOD

A questionnaire was administered to identify factors determining helmet use. Intention to obey the law, and perceived risk of being caught if not obeying the law were included as additional constructs. Path analysis was used to extract the strongest influences on intention and behaviour. The social marketing campaign was evaluated through t-test comparisons after propensity score matching and generalised linear modelling (GLM) were applied to adjust for the same covariates.

RESULTS

400 cyclists aged 25-54 years completed the questionnaire. Self-efficacy and Intention were most predictive of intention to wear a helmet, which, moderated by planning, strongly predicted behaviour. Perceived risk and outcome expectancies had no significant impact on intention. GLM showed that exposure to the campaign was significantly associated with higher values in self-efficacy, intention and bicycle helmet use.

CONCLUSION

Self-efficacy and planning are important points of action for promoting helmet use. Social marketing campaigns that remind people of appropriate preventive action have an impact on behaviour.

Pattern and spectrum of tornado injury and its geographical information system distribution in Yancheng, China: a cross-sectional study

OBJECTIVES

Few studies of tornado injuries have considered differences related to damage levels and Enhanced-Fujita (EF) scale ratings. This study aimed to evaluate the pattern, spectrum and geographical distribution of injuries related to the Yancheng tornado and provide guidelines for effective emergency medical strategies.

SETTING

The study was conducted at three hospitals which treated patients with injuries related to the tornado in Yancheng, China.

PARTICIPANTS

We obtained the records of 451 patients with tornado-related injuries. Of these, 401 valid trauma medical records were included; 50 other records were excluded for insufficient information. Informed consent was obtained from all patients by telephone.

MAIN OUTCOME MEASURES

We analysed patients' injury sites and types and used the abbreviated injury scale (AIS) to standardise injury severity. Geographical information system and non-parametric tests were used to analyse the effects of geographical factors on casualties.

RESULTS

Women, middle-aged/elderly individuals (age>45 years) and children/adolescents (<18 years) accounted for 51.62%, 77.30% and 12.47% of injured patients, respectively. This caused a dumbbell-shaped age distribution. Head (46.63%), body surface (39.90%) and lower-limb (29.43%) injuries were common, as were soft-tissue injuries (90.77%), fractures (38.90%) and organ damage (19.70%). Minor injuries (AIS=1) were common (60.85%), whereas critical/fatal injuries (AIS≥5) were very rare (2.50%). Although the densities of injury varied among damage levels and EF ratings for different areas, area-wise differences in injury severity (AIS scores) were not significant (p>0.05).

CONCLUSION

We recommend the use of helmets to prevent head injuries caused by tornadoes and suggest prioritising the treatment of high-risk head and multiple-organ injuries. Additionally, medical rescuers should follow the 'same quality and different quantity' principle: the injured in all affected areas should receive equal attention, but numbers of medical personnel should be allocated based on the level of effects from the tornado.

Developing an Acoustic Sensing Yarn for Health Surveillance in a Military Setting

Overexposure to high levels of noise can cause permanent hearing disorders, which have a significant adverse effect on the quality of life of those affected. Injury due to noise can affect people in a variety of careers including construction workers, factory workers, and members of the armed forces. By monitoring the noise exposure of workers, overexposure can be avoided and suitable protective equipment can be provided. This work focused on the creation of a noise dosimeter suitable for use by members of the armed forces, where a discrete dosimeter was integrated into a textile helmet cover. In this way the sensing elements could be incorporated very close to the ears, providing a highly representative indication of the sound level entering the body, and also creating a device that would not interfere with military activities. This was achieved by utilising commercial microelectromechanical system microphones integrated within the fibres of yarn to create an acoustic sensing yarn. The acoustic sensing yarns were fully characterised over a range of relevant sound levels and frequencies at each stage in the yarn production process. The yarns were ultimately integrated into a knitted helmet cover to create a functional acoustic sensing helmet cover prototype.

Evaluation of possible head injuries ensuing a cricket ball impact

BACKGROUND AND OBJECTIVE

The aim of this research is to study the behaviour of a human head during the event of an impact of a cricket ball. While many recent incidents were reported in relation to head injuries caused by the impact of cricket balls, there is no clear information available in the published literature about the possible threat levels and the protection level of the current protective equipment. This research investigates the effects of an impact of a cricket ball on a human head and the level of protection offered by the existing standard cricket helmet.

METHOD

An experimental program was carried out to measure the localised pressure caused by the impact of standard cricket balls. The balls were directed at a speed of 110 km/h on a 3D printed head model, with and without a standard cricket helmet. Numerical simulations were carried out using advanced finite element package LS-DYNA to validate the experimental results.

RESULTS

The experimental and numerical results showed approximately a 60% reduction in the pressure on the head model when the helmet was used. Both frontal and side impact resulted in head acceleration values in the range of 225-250 g at a ball speed of 110 km/h. There was a 36% reduction observed in the peak acceleration of the brain when wearing a helmet. Furthermore, numerical simulations showed a 67% reduction in the force on the skull and a 95% reduction in the skull internal energy when introducing the helmet.

CONCLUSIONS

(1) Upon impact, high localised pressure could cause concussion for a player without helmet. (2) When a helmet was used, the acceleration of the brain observed in the numerical results was at non-critical levels according to existing standards. (3) A significant increase in the threat levels was observed for a player without helmet, based on force, pressure, acceleration and energy criteria, which resulted in recommending the compulsory use of the cricket helmet. (4) Numerical results showed a good correlation with experimental results and hence, the numerical technique used in this study can be recommended for future applications.

Bicycle helmets are protective against facial injuries, including facial fractures: a meta-analysis

Cycling is a popular activity. However there are risks associated with cycling, including facial injury. Helmets are often worn to prevent head injury. Evidence for their protection against facial injury is limited. This meta-analysis investigated the effect of bicycle helmets on the incidence of facial injury. The PubMed/MEDLINE, Google Scholar, and Cochrane Library databases were searched. Studies included were observational and involved adult participants. Paediatric studies, studies on helmet legislation, and those combining facial injuries with other injury types were excluded. The studies were evaluated by two reviewers. Risk of bias was assessed using the RevMan bias assessment tool. Odds ratios (OR) were extracted for facial injuries and facial fractures. Two meta-analyses were performed using these categories. Nine of the 102 studies identified were included. Helmets were protective against facial injury (OR 0.69, 95% confidence interval 0.63-0.75, P<0.0001). Five studies reported facial fracture rates; helmets were protective against these also (OR 0.79 95% confidence interval 0.70-0.90, P=0.0003). There are no randomized controlled trials on this topic and the number of studies available is small. Bicycle helmets offer protection against facial injuries and this should be considered by cyclists when deciding whether or not to use one.

Fit, stability and comfort assessment of custom-fitted bicycle helmet inner liner designs, based on 3D anthropometric data

Research has demonstrated that a better-fitted bicycle helmet offers improved protection to the rider during an impact. Nowadays, bicycle helmets in the market that range in size from small/medium to medium/large might not fit the diverse range of human head shapes and dimensions. 3D scanning was used to create 3D head shape databases of 20 participants who volunteered for the study. We developed new custom-fitted helmet inner liners, based on the 3D head shape of two sub-groups of participants, to map their head sizes and contours closely to the conventional Medium (M) and Large (L) sizes as described in from AS/NZS 2512.1: 2009. The new custom-fitted helmet was compared with the helmet available in the market place in a dynamics stability test and from participants' subjective feedback. A significant reduction in the angle of helmet rotation on the headform in the lateral direction was recorded for the custom-fitted helmet. A Wilcoxon signed-rank test was conducted to evaluate participants' feedback on the helmets according to different area definitions. The overall fit and comfort and the top region of the new helmet were significantly improved. However, no difference was found at the significant level of 0.05 for the front and rear region of the new helmet.

Comparisons between Shikoro-type helmet with no hood and typical fire protective helmets with hood in a hot and humid environment

The purpose of this study was to evaluate physiological and subjective responses while wearing the Shikoro-type helmet for firefighters when compared to typical helmets. Eight firefighters conducted a 30-min exercise at a 5 km h^-1 in three helmet conditions at an air temperature of 32 °C with 70%RH. The results showed that no significant differences in rectal, mean skin temperature and physiological strain index among the three conditions were found during exercise and recovery. Skin temperatures on the cheek, ear and neck during exercise were significantly lower for the Shikoro-type condition (p < 0.05), but forehead temperature was greater for the Shikoro-type helmet when compared to the other conditions (p < 0.05). Statistical differences in thermal sensation and thermal comfort for overall and local body regions were not found among the three conditions. These results imply that the Shikoro-type helmet had local advantages in reducing skin temperatures on the face and neck. Practitioner Summary: Firefighters wear their helmet with its hood to protect the head and neck but a Shikoro type helmet has no fire protective hood. This study aimed to evaluate the comfort function of Shikoro helmet along with typical helmets. The results demonstrated thermal benefits of the Shikoro helmet on the head.

Neck Kinematics and Electromyography While Wearing Head Supported Mass During Running

BACKGROUND

Advanced combat helmets (ACH) coupled with night-vision goggles (NVG) are required for tactical athletes during training and service. Head and neck injuries due to head supported mass (HSM) are a common occurrence in military personnel. The current study aimed to investigate the effects of HSM on neck muscle fatigue that may lead to chronic stress and injury of the head and neck.

METHODS

Subjects wore an ACH and were affixed with electromagnetic sensors to obtain kinematic data, as well as EMG electrodes to obtain muscle activations of bilateral sternocleidomastoid, upper trapezius, and paraspinal muscles while running on a treadmill. Subjects performed a 2-min warmup at a walking pace, a 5-min warmup jog, running at a pace equal to 90% maximum heart rate until absolute fatigue, and lastly a 2-min cooldown at a walking pace. Kinematic and EMG data were collected over each 2-min interval. Days later, the same subjects wore the same ACH in addition to the NVG and performed the same protocol as the first session.

RESULTS

This study showed significant differences in muscle activation of the right upper trapezius [F(1,31) = 10.100] and both sternocleidomastoid [F(1,31) = 12.280] muscles from pre-fatigue to absolute fatigue. There were no significant differences noted in the kinematic variables.

DISCUSSION

This study suggests that HSM can fatigue bilateral neck flexors and rotators, as well as fatigue the neck extensors and rotators on the contralateral side of the mounted NVG.Hanks MM, Sefton JM, Oliver GD. Neck kinematics and electromyography while wearing head supported mass during running. Aerosp Med Hum Perform. 2018; 89(1):9-13.

Under-reporting bicycle accidents to police in the COST TU1101 international survey: Cross-country comparisons and associated factors

Police crash reports are often the main source for official data in many countries. However, with the exception of fatal crashes, crashes are often underreported in a biased manner. Consequently, the countermeasures adopted according to them may be inefficient. In the case of bicycle crashes, this bias is most acute and it probably varies across countries, with some of them being more prone to reporting accidents to police than others. Assessing if this bias occurs and the size of it can be of great importance for evaluating the risks associated with bicycling. This study utilized data collected in the COST TU1101 action "Towards safer bicycling through optimization of bicycle helmets and usage". The data came from an online survey that included questions related to bicyclists' attitudes, behaviour, cycling habits, accidents, and patterns of use of helmets. The survey was filled by 8655 bicyclists from 30 different countries. After applying various exclusion factors, 7015 questionnaires filled by adult cyclists from 17 countries, each with at least 100 valid responses, remained in our sample. The results showed that across all countries, an average of only 10% of all crashes were reported to the police, with a wide range among countries: from a minimum of 0.0% (Israel) and 2.6% (Croatia) to a maximum of a 35.0% (Germany). Some factors associated with the reporting levels were type of crash, type of vehicle involved, and injury severity. No relation was found between the likelihood of reporting and the cyclist's gender, age, educational level, marital status, being a parent, use of helmet, and type of bicycle. The significant under-reporting - including injury crashes that do not lead to hospitalization - justifies the use of self-report survey data for assessment of bicycling crash patterns as they relate to (1) crash risk issues such as location, infrastructure, cyclists' characteristics, and use of helmet and (2) strategic approaches to bicycle crash prevention and injury reduction.

Face shield design against blast-induced head injuries

Blast-induced traumatic brain injury has been on the rise in recent years because of the increasing use of improvised explosive devices in conflict zones. Our study investigates the response of a helmeted human head subjected to a blast of 1 atm peak overpressure, for cases with and without a standard polycarbonate (PC) face shield and for face shields comprising of composite PC and aerogel materials and with lateral edge extension. The novel introduction of aerogel into the laminate face shield is explored and its wave-structure interaction mechanics and performance in blast mitigation is analysed. Our numerical results show that the face shield prevented direct exposure of the blast wave to the face and help delays the transmission of the blast to reduce the intracranial pressures (ICPs) at the parietal lobe. However, the blast wave can diffract and enter the midface region at the bottom and side edges of the face shield, resulting in traumatic brain injury. This suggests that the bottom and sides of the face shield are important regions to focus on to reduce wave ingress. The laminated PC/aerogel/PC face shield yielded higher peak positive and negative ICPs at the frontal lobe, than the original PC one. For the occipital and temporal brain regions, the laminated face shield performed better than the original. The composite face shield with extended edges reduced ICP at the temporal lobe but increases ICP significantly at the parietal lobe, which suggests that a greater coverage may not lead to better mitigating effects.

Reconstruction of head impacts in FIS World Cup alpine skiing

INTRODUCTION

Prior to the 2013/2014 season, the International Ski Federation (FIS) increased the helmet testing speed from 5.4 to 6.8 m/s for alpine downhill, super-G and giant slalom. Whether this increased testing speed reflects head impact velocities in real head injury situations on snow is unclear. We therefore investigated the injury mechanisms and gross head impact biomechanics in seven real head injury situations among World Cup (WC) alpine skiers.

METHODS

We analysed nine head impacts from seven head injury videos from the FIS Injury Surveillance System, throughout nine WC seasons (2006-2015) in detail. We used commercial video-based motion analysis software to estimate head impact kinematics in two dimensions, including directly preimpact and postimpact, from broadcast video. The sagittal plane angular movement of the head was also measured using angle measurement software.

RESULTS

In seven of nine head impacts, the estimated normal to slope preimpact velocity was higher than the current FIS helmet rule of 6.8 m/s (mean 8.1 (±SD 0.6) m/s, range 1.9±0.8 to 12.1±0.4 m/s). The nine head impacts had a mean normal to slope velocity change of 9.3±1.0 m/s, range 5.2±1.1 to 13.5±1.3 m/s. There was a large change in sagittal plane angular velocity (mean 43.3±2.9 rad/s (range 21.2±1.5 to 64.2±3.0 rad/s)) during impact.

CONCLUSION

The estimated normal to slope preimpact velocity was higher than the current FIS helmet rule of 6.8 m/s in seven of nine head impacts.

Aerodynamic study of time-trial helmets in cycling racing using CFD analysis

The aerodynamic drag of three different time-trial cycling helmets was analyzed numerically for two different cyclist head positions. Computational Fluid Dynamics (CFD) methods were used to investigate the detailed airflow patterns around the cyclist for a constant velocity of 15 m/s without wind. The CFD simulations have focused on the aerodynamic drag effects in terms of wall shear stress maps and pressure coefficient distributions on the cyclist/helmet system. For a given head position, the helmet shape, by itself, obtained a weak effect on a cyclist's aerodynamic performance (<1.5%). However, by varying head position, a cyclist significantly influences aerodynamic performance; the maximum difference between both positions being about 6.4%. CFD results have also shown that both helmet shape and head position significantly influence drag forces, pressure and wall shear stress distributions on the whole cyclist's body due to the change in the near-wake behavior and in location of corresponding separation and attachment areas around the cyclist.

Neck Injury Response in High Vertical Accelerations and its Algorithmical Formalization to Mitigate Neck Injuries

Tank Automotive Research, Development and Engineering Center (TARDEC) conducted a comprehensive analysis of data collected during the evaluation of head and neck impact during injurious and non-injurious loading. This evaluation included impact velocity, helmet to roof clearance, and neck angle using a fully instrumented Hybrid III head and neck assembly. The results of this effort were compared against post mortem human subject (PMHS) data from similar testing conducted in conjunction with the Warrior Injury Assessment Manikin (WIAMan) program. The results identified the most severe helmet to roof clearance and neck angles. TARDEC used this knowledge as the foundation for continued research into head and neck impact injury mitigation through the use of passive technology and interior vehicle design.

Head impact exposure measured in a single youth football team during practice drills

OBJECTIVE This study evaluated the frequency, magnitude, and location of head impacts in practice drills within a youth football team to determine how head impact exposure varies among different types of drills. METHODS On-field head impact data were collected from athletes participating in a youth football team for a single season. Each athlete wore a helmet instrumented with a Head Impact Telemetry (HIT) System head acceleration measurement device during all preseason, regular season, and playoff practices. Video was recorded for all practices, and video analysis was performed to verify head impacts and assign each head impact to a specific drill. Eleven drills were identified: dummy/sled tackling, install, special teams, Oklahoma, one-on-one, open-field tackling, passing, position skill work, multiplayer tackle, scrimmage, and tackling drill stations. Generalized linear models were fitted to log-transformed data, and Wald tests were used to assess differences in head accelerations and impact rates. RESULTS A total of 2125 impacts were measured during 30 contact practices in 9 athletes (mean age 11.1 ± 0.6 years, mean mass 44.9 ± 4.1 kg). Open-field tackling had the highest median and 95th percentile linear accelerations (24.7 g and 97.8 g, respectively) and resulted in significantly higher mean head accelerations than several other drills. The multiplayer tackle drill resulted in the highest head impact frequency, with an average of 0.59 impacts per minute per athlete, but the lowest 95th percentile linear accelerations of all drills. The front of the head was the most common impact location for all drills except dummy/sled tackling. CONCLUSIONS Head impact exposure varies significantly in youth football practice drills, with several drills exposing athletes to high-magnitude and/or high-frequency head impacts. These data suggest that further study of practice drills is an important step in developing evidence-based recommendations for modifying or eliminating certain high-intensity drills to reduce head impact exposure and injury risk for all levels of play.

Investigation of spatial resolution improvement by use of a mouth-insert detector in the helmet PET scanner

The dominant factor limiting the intrinsic spatial resolution of a positron emission tomography (PET) system is the size of the crystal elements in the detector. To increase sensitivity and achieve high spatial resolution, it is essential to use advanced depth-of-interaction (DOI) detectors and arrange them close to the subject. The DOI detectors help maintain high spatial resolution by mitigating the parallax error caused by the thickness of the scintillator near the peripheral regions of the field-of-view. As an optimal geometry for a brain PET scanner, with high sensitivity and spatial resolution, we proposed and developed the helmet-chin PET scanner using 54 four-layered DOI detectors consisting of a 16 × 16 × 4 array of GSOZ scintillator crystals with dimensions of 2.8 × 2.8 × 7.5 mm³. All the detectors used in the helmet-chin PET scanner had the same spatial resolution. In this study, we conducted a feasibility study of a new add-on detector arrangement for the helmet PET scanner by replacing the chin detector with a segmented crystal cube, having high spatial resolution in all directions, which can be placed inside the mouth. The crystal cube (which we have named the mouth-insert detector) has an array of 20 × 20 × 20 LYSO crystal segments with dimensions of 1 × 1 × 1 mm³. Thus, the scanner is formed by the combination of the helmet and mouth-insert detectors, and is referred to as the helmet-mouth-insert PET scanner. The results show that the helmet-mouth-insert PET scanner has comparable sensitivity and improved spatial resolution near the center of the hemisphere, compared to the helmet-chin PET scanner.

Bicycle Helmets Save More than Heads: Experience from a Pediatric Level I Trauma Hospital

We studied pediatric bicycle accident victims (age ≤ 15 years) who were treated at our pediatric Level I trauma center during a 10-year period. Demographic data, injury severity, hospital course, and hospital cost data were collected. We compared the children who were helmeted to those who were unhelmeted. Our study cohort consisted of 516 patients. Patients were mostly male (70.2%) and white (84.7%); the median age was nine years. There were 101 children in the helmet group and 415 children in the unhelmeted group. Helmeted children were more likely to have private insurance (68.3% vs 35.9%, P < 0.001). Unhelmeted children were more likely to sustain multiple injuries (40% vs 25.7%, P = 0.008), meet our trauma activation criteria (45.5% vs 16.8%, P < 0.001), and be admitted to the hospital (42.4% vs 14.9%, P < 0.001). Helmeted children were less likely to sustain brain injuries (15.8% vs 25.8%, P = 0.037), skull fractures (1% vs 10.8%, P = 0.001), and facial fractures (1% vs 6%, P = 0.040). Median hospital costs were more expensive in the unhelmeted group. Helmet usage was suboptimal. Although most children sustained relatively minor injuries, the unhelmeted children had more injuries and higher costs than those who used helmets. Injury prevention programs are warranted.