Injuries in Full-Scale Vehicle Side Impact Moving Deformable Barrier and Pole Tests Using Postmortem Human Subjects

OBJECTIVE

To conduct near-side moving deformable barrier (MDB) and pole tests with postmortem human subjects (PMHS) in full-scale modern vehicles, document and score injuries, and examine the potential for angled chest loading in these tests to serve as a data set for dummy biofidelity evaluations and computational modeling.

METHODS

Two PMHS (outboard left front and rear seat occupants) for MDB and one PMHS (outboard left front seat occupant) for pole tests were used. Both tests used sedan-type vehicles from same manufacturer with side airbags. Pretest x-ray and computed tomography (CT) images were obtained. Three-point belt-restrained surrogates were positioned in respective outboard seats. Accelerometers were secured to T1, T6, and T12 spines; sternum and pelvis; seat tracks; floor; center of gravity; and MDB. Load cells were used on the pole. Biomechanical data were gathered at 20 kHz. Outboard and inboard high-speed cameras were used for kinematics. X-rays and CT images were taken and autopsy was done following the test. The Abbreviated Injury Scale (AIS) 2005 scoring scheme was used to score injuries.

RESULTS

MDB test: male (front seat) and female (rear seat) PMHS occupant demographics: 52 and 57 years, 177 and 166 cm stature, 78 and 65 kg total body mass. Demographics of the PMHS occupant in the pole test: male, 26 years, 179 cm stature, and 84 kg total body mass. Front seat PMHS in MDB test: 6 near-side rib fractures (AIS = 3): 160-265 mm vertically from suprasternal notch and 40-80 mm circumferentially from center of sternum. Left rear seat PMHS responded with multiple bilateral rib fractures: 9 on the near side and 5 on the contralateral side (AIS = 3). One rib fractured twice. On the near and contralateral sides, fractures were 30-210 and 20-105 mm vertically from the suprasternal notch and 90-200 and 55-135 mm circumferentially from the center of sternum. A fracture of the left intertrochanteric crest occurred (AIS = 3). Pole test PMHS had one near-side third rib fracture. Thoracic accelerations of the 2 occupants were different in the MDB test. Though both occupants sustained positive and negative x-accelerations to the sternum, peak magnitudes and relative changes were greater for the rear than the front seat occupant. Magnitudes of the thoracic and sternum accelerations were lower in the pole test.

CONCLUSIONS

This is the first study to use PMHS occupants in MDB and pole tests in the same recent model year vehicles with side airbag and head curtain restraints. Injuries to the unilateral thorax for the front seat PMHS in contrast to the bilateral thorax and hip for the rear seat occupant in the MDB test indicate the effects of impact on the seating location and restraint system. Posterolateral locations of fractures to the front seat PMHS are attributed to constrained kinematics of occupant interaction with torso side airbag restraint system. Angled loading to the rear seat occupant from coupled sagittal and coronal accelerations of the sternum representing anterior thorax loading contributed to bilateral fractures. Inward bending initiated by the distal femur complex resulting in adduction of ipsilateral lower extremity resulted in intertrochanteric fracture to the rear seat occupant. These results serve as a data set for evaluating the biofidelity of the WorldSID and federalized side impact dummies and assist in validating human body computational models, which are increasingly used in crashworthiness studies.

Differences in long-term medical consequences depending on impact direction involving passenger cars

OBJECTIVE

There is limited knowledge of the long-term medical consequences for occupants injured in car crashes in various impact directions. Thus, the objective was to evaluate whether injuries leading to permanent medical impairment differ depending on impact direction.

METHODS

In total, 36,743 injured occupants in car crashes that occurred between 1995 and 2011 were included. All initial injuries (n = 61,440) were classified according to the Abbreviated Injury Scale (AIS) 2005. Injured car occupants were followed for at least 3 years to assess permanent medical impairment. The data were divided into different groups according to impact direction and levels of permanent impairment. The risk of permanent medical impairment was established for different body regions and injury severity levels, according to AIS.

RESULTS

It was found that almost 12% of all car occupants sustained a permanent medical impairment. Given an injury, car occupants involved in rollover crashes had the highest overall risk to sustain a permanent medical impairment. Half of the head injuries leading to long-term consequences occurred in frontal impacts. Far-side occupants had almost the same risk as near-side occupants. Occupants who sustained a permanent medical impairment from cervical spine injuries had similar risk in all impact directions (13%) except from rollover (17%). However, these injuries occurred more often in rear crashes. Most of the injuries leading to long-term consequences were classified as minor injuries by AIS for all impact directions.

CONCLUSIONS

Studying crash data from a perspective of medical impairment is important to identify injuries that might not be prioritized only considering the AIS but might lead to lower quality of life for the occupant and also costs for society. These results can be used for road transport system strategies and for making priority decisions in vehicle design.

Occurrence of serious injury in real-world side impacts of vehicles with good side-impact protection ratings

OBJECTIVE

The Insurance Institute for Highway Safety (IIHS) introduced its side impact consumer information test program in 2003. Since that time, side airbags and structural improvements have been implemented across the fleet and the proportion of good ratings has increased to 93% of 2012-2014 model year vehicles. Research has shown that drivers of good-rated vehicles are 70% less likely to die in a left-side crash than drivers of poor-rated vehicles. Despite these improvements, side impact fatalities accounted for about one quarter of passenger vehicle occupant fatalities in 2012. This study is a detailed analysis of real-world cases with serious injury resulting from side crashes of vehicles with good ratings in the IIHS side impact test.

METHODS

NASS-CDS and Crash Injury Research and Engineering Network (CIREN) were queried for occupants of good-rated vehicles who sustained an Abbreviated Injury Scale (AIS) ≥ 3 injury in a side-impact crash. The resulting 110 cases were categorized by impact configuration and other factors that contributed to injury. Patterns of impact configuration, restraint performance, and occupant injury were identified and discussed in the context of potential upgrades to the current IIHS side impact test.

RESULTS

Three quarters of the injured occupants were involved in near-side impacts. For these occupants, the most common factors contributing to injury were crash severities greater than the IIHS test, inadequate side-airbag performance, and lack of side-airbag coverage for the injured body region. In the cases where an airbag was present but did not prevent the injury, occupants were often exposed to loading centered farther forward on the vehicle than in the IIHS test. Around 40% of the far-side occupants were injured from contact with the struck-side interior structure, and almost all of these cases were more severe than the IIHS test. The remaining far-side occupants were mostly elderly and sustained injury from the center console, instrument panel, or seat belt. In addition, many far-side occupants were likely out of position due to events preceding the side impact and/or being unbelted.

CONCLUSION

Individual changes to the IIHS side impact test have the potential to reduce the number of serious injuries in real-world crashes. These include impacting the vehicle farther forward (relevant to 28% of all cases studied), greater test severity (17%), the inclusion of far-side occupants (9%), and more restrictive injury criteria (9%). Combinations of these changes could be more effective.

New Methodology for an Expert-Designed Map From International Classification of Diseases (ICD) to Abbreviated Injury Scale (AIS) 3+ Severity Injury

OBJECTIVE

There has been a longstanding desire for a map to convert International Classification of Diseases (ICD) injury codes to Abbreviated Injury Scale (AIS) codes to reflect the severity of those diagnoses. The Association for the Advancement of Automotive Medicine (AAAM) was tasked by European Union representatives to create a categorical map classifying diagnoses codes as serious injury (Abbreviated Injury Scale [AIS] 3+), minor/moderate injury (AIS 1/2), or indeterminate. This study's objective was to map injury-related ICD-9-CM (clinical modification) and ICD-10-CM codes to these severity categories.

METHODS

Approximately 19,000 ICD codes were mapped, including injuries from the following categories: amputations, blood vessel injury, burns, crushing injury, dislocations/sprains/strains, foreign body, fractures, internal organ, nerve/spinal cord injury, intracranial, laceration, open wounds, and superficial injury/contusion. Two parallel activities were completed to create the maps: (1) An in-person expert panel and (2) an electronic survey. The panel consisted of expert users of AIS and ICD from North America, the United Kingdom, and Australia. The panel met in person for 5 days, with follow-up virtual meetings to create and revise the maps. Additional qualitative data were documented to resolve potential discrepancies in mapping. The electronic survey was completed by 95 injury coding professionals from North America, Spain, Australia, and New Zealand over 12 weeks. ICD-to-AIS maps were created for: ICD-9-CM and ICD-10-CM. Both maps indicated whether the corresponding AIS 2005/Update 2008 severity score for each ICD code was AIS 3+, 1/2, or indeterminable. Though some ICD codes could be mapped to multiple AIS codes, the maximum severity of all potentially mapped injuries determined the final severity categorization.

RESULTS

The in-person panel consisted of 13 experts, with 11 Certified AIS specialists (CAISS) with a median of 8 years and an average of 15 years of coding experience. Consensus was reached for AIS severity categorization for all injury-related ICD codes. There were 95 survey respondents, with a median of 8 years of injury coding experience. Approximately 15 survey responses were collected per ICD code. Results from the 2 activities were compared, and any discrepancies were resolved using additional qualitative and quantitative data from the in-person panel and survey results, respectively.

CONCLUSIONS

Robust maps of ICD-9-CM and ICD-10-CM injury codes to AIS severity categories (3+ versus <3) were successfully created from an in-person panel discussion and electronic survey. These maps provide a link between the common ICD diagnostic lexicons and the AIS severity coding system and are of value to injury researchers, public health scientists, and epidemiologists using large databases without available AIS coding.

Estimated injury risk for specific injuries and body regions in frontal motor vehicle crashes

OBJECTIVE

Injury risk curves estimate motor vehicle crash (MVC) occupant injury risk from vehicle, crash, and/or occupant factors. Many vehicles are equipped with event data recorders (EDRs) that collect data including the crash speed and restraint status during a MVC. This study's goal was to use regulation-required data elements for EDRs to compute occupant injury risk for (1) specific injuries and (2) specific body regions in frontal MVCs from weighted NASS-CDS data.

METHODS

Logistic regression analysis of NASS-CDS single-impact frontal MVCs involving front seat occupants with frontal airbag deployment was used to produce 23 risk curves for specific injuries and 17 risk curves for Abbreviated Injury Scale (AIS) 2+ to 5+ body region injuries. Risk curves were produced for the following body regions: head and thorax (AIS 2+, 3+, 4+, 5+), face (AIS 2+), abdomen, spine, upper extremity, and lower extremity (AIS 2+, 3+). Injury risk with 95% confidence intervals was estimated for 15-105 km/h longitudinal delta-Vs and belt status was adjusted for as a covariate.

RESULTS

Overall, belted occupants had lower estimated risks compared to unbelted occupants and the risk of injury increased as longitudinal delta-V increased. Belt status was a significant predictor for 13 specific injuries and all body region injuries with the exception of AIS 2+ and 3+ spine injuries. Specific injuries and body region injuries that occurred more frequently in NASS-CDS also tended to carry higher risks when evaluated at a 56 km/h longitudinal delta-V. In the belted population, injury risks that ranked in the top 33% included 4 upper extremity fractures (ulna, radius, clavicle, carpus/metacarpus), 2 lower extremity fractures (fibula, metatarsal/tarsal), and a knee sprain (2.4-4.6% risk). Unbelted injury risks ranked in the top 33% included 4 lower extremity fractures (femur, fibula, metatarsal/tarsal, patella), 2 head injuries with less than one hour or unspecified prior unconsciousness, and a lung contusion (4.6-9.9% risk). The 6 body region curves with the highest risks were for AIS 2+ lower extremity, upper extremity, thorax, and head injury and AIS 3+ lower extremity and thorax injury (15.9-43.8% risk).

CONCLUSIONS

These injury risk curves can be implemented into advanced automatic crash notification (AACN) algorithms that utilize vehicle EDR measurements to predict occupant injury immediately following a MVC. Through integration with AACN, these injury risk curves can provide emergency medical services (EMS) and other patient care providers with information on suspected occupant injuries to improve injury detection and patient triage.

Assessment of Bilateral Thoracic Loading on the Near-Side Occupant Due to Occupant-to-Occupant Interaction in Vehicle Crash Tests

OBJECTIVE

This study aims, by means of the WorldSID 50th percentile male, to evaluate thoracic loading and injury risk to the near-side occupant due to occupant-to-occupant interaction in combination with loading from an intruding structure.

METHOD

Nine vehicle crash tests were performed with a 50th percentile WorldSID male dummy in the near-side (adjacent to the intruding structure) seat and a THOR or ES2 dummy in the far-side (opposite the intruding structure) seat. The near-side seated WorldSID was equipped with 6 + 6 IR-Traccs (LH and RH) in the thorax/abdomen enabling measurement of bilateral deflection. To differentiate deflection caused by the intrusion, and the deflection caused by the neighboring occupant, time history curves were analyzed. The crash tests were performed with different modern vehicles, equipped with thorax side airbags and inflatable curtains, ranging from a compact car to a large sedan, and in different loading conditions such as car-to-car, barrier, and pole tests. Lateral delta V based on vehicle tunnel acceleration and maximum residual intrusion at occupant position were used as a measurement of crash severity to compare injury measurements.

RESULT

In the 9 vehicle crash tests, thoracic loading, induced by the intruding structure as well as from the far-side occupant, varied due to the size and structural performance of the car as well as the severity of the crash. Peak deflection on the thoracic outboard side occurred during the first 50 ms of the event. Between 70 to 150 ms loading induced by the neighboring occupant occurred and resulted in an inboard-side peak deflection and viscous criterion. In the tests where the target vehicle lateral delta V was below 30 km/h and intrusion less than 200 mm, deflections were low on both the outboard (20-40 mm) and inboard side (10-15 mm). At higher crash severities, delta V 35 km/h and above as well as intrusions larger than 350 mm, the inboard deflections (caused by interaction to the far-side occupant) were of the same magnitude or even higher (30-70 mm) than the outboard deflections (30-50 mm).

CONCLUSION

A WorldSID 50th percentile male equipped with bilateral IR-Traccs can detect loading to the thorax from a neighboring occupant making injury risk assessment feasible for this type of loading. At crash severities resulting in a delta V above 35 km/h and intrusions larger than 350 mm, both the inboard deflection and VC resulted in high risks of Abbreviated Injury Scale (AIS) 3+ injury, especially for a senior occupant.

Risk of permanent medical impairment (RPMI) in car crashes correlated to age and gender

OBJECTIVE

As fatalities from car crashes decrease, focus on medical impairment following car crashes becomes more essential. This study assessed the risk of permanent medical impairment based on car occupant injuries. The aim was to study whether the risk of permanent medical impairment differs depending on age and gender.

METHODS

In total, 36,744 injured occupants in car crashes that occurred between 1995 and 2010 were included. All initial injuries (n = 61,440) were classified according to the Abbreviated Injury Scale (AIS) 2005. If a car occupant still had residual symptoms 3 years after a crash, the case was classed as a permanent medical impairment. In total, 5,144 injuries led to permanent medical impairment. The data were divided into different groups according to age and gender as well as levels of permanent impairment. The risk of permanent medical impairment was established for different body regions and injury severity levels, according to the AIS.

RESULTS

The cervical spine was the body region that had the highest number of diagnoses, and occupants who sustained injuries to the upper and lower extremities had the highest risk of medical impairment for both genders. Females aged 60 and above had a higher risk of permanent medical impairment from fractures in the extremities compared to males in the same age group and younger females. Females aged 44 or younger had a higher risk of permanent medical impairment from whiplash-associated disorders (WAD) than males in the same age group. Minor and moderate injuries (AIS 1-2) had a higher risk of permanent medical impairment among older car occupants compared to younger ones.

CONCLUSIONS

Differences in long-term outcome were dependent on both gender and age. Differences between age groups were generally greater than between genders. The vast majority of permanent medical impairments resulted from diagnoses with a low risk of fatality. The results emphasize the impact of age and gender in long-term consequences from car crashes. They could be used when designing safety technology in cars as well as to improve health care by contributing to better allocation of rehabilitation resources following trauma.

A prospective study of children aged <16 years in motor vehicle collisions in Norway: severe injuries are observed predominantly in older children and are associated with restraint misuse

OBJECTIVE

The implementation of the compulsory wearing of seat belts (SBs) for children and improvements in child restraint systems have reduced the number of deaths and severe injuries among children involved in motor vehicle (MV) collisions (MVCs). Establishing the characteristics predictive of such injuries may provide the basis for targeted safety campaigns and lead to a further reduction in mortality and morbidity among children involved in MVCs. This study performed a multidisciplinary investigation among child occupants involved in MVCs to elucidate injury mechanisms, evaluate the safety measures used and determine the characteristics that are predictive of injury.

METHODS

A prospective study was conducted of all child occupants aged <16 years involved in severe MVCs in south-eastern Norway during 2009-2013. The exterior and interior of the MVs were investigated and the injured children were medically examined. Supplementary information was obtained from witnesses, the crash victims, police reports, medical records and reconstructions. Each case was reviewed by a multidisciplinary team to assess the mechanism of injury.

RESULTS

In total, 158 child occupants involved in 100 MVCs were investigated, of which 27 (17%) exhibited Abbreviated Injury Scale (AIS) scores of 2+ injuries and 15 (9%) exhibited AIS 3+ injuries. None of the children died. Of those with AIS 2+ injuries (n=27), 89% (n=24) were involved in frontal impact collisions and 11% (3/27) were involved in side impacts. Multivariate analysis revealed that restraint misuse, age, the prevailing lighting conditions and ΔV were all independently correlated with AIS 2+ injuries. Safety errors were found in 74% (20/27) of those with AIS 2+ injuries and 93% (14/15) of those with AIS 3+ injuries. The most common safety error was misuse of restraints, and in particular loose and/or improperly positioned SBs.

CONCLUSION

The risk of injury among child occupants is significantly higher when the child occupants are exposed to safety errors within the interior of the vehicle. Future campaigns should focus on the prevention of restraint misuse and unsecured objects in the passenger compartment or boot.

Effect of weight, height and BMI on injury outcome in side impact crashes without airbag deployment

A comprehensive analysis is performed to evaluate the effect of weight, height and body mass index (BMI) of occupants on side impact injuries at different body regions. The accident dataset for this study is based on the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) for accident year 2000-08. The mean BMI values for driver and front passenger are estimated from all types of crashes using NASS database, which clearly indicates that mean BMI has been increasing over the years in the USA. To study the effect of BMI in side impact injuries, BMI was split into three groups namely (1) thin (BMI<21), (2) normal (BMI 24-27), (3) obese (BMI>30). For more clear identification of the effect of BMI in side impact injuries, a minimum gap of three BMI is set in between each adjacent BMI groups. Car model years from MY1995-1999 to MY2000-2008 are chosen in order to identify the degree of influence of older and newer generation of cars in side impact injuries. Impact locations particularly side-front (F), side-center (P) and side-distributed (Y) are chosen for this analysis. Direction of force (DOF) considered for both near side and far side occupants are 8 o'clock, 9 o'clock, 10 o'clock and 2 o'clock, 3 o'clock and 4 o'clock respectively. Age <60 years is also one of the constraints imposed on data selection to minimize the effect of bone strength on the occurrence of occupant injuries. AIS2+ and AIS3+ injury risk in all body regions have been plotted for the selected three BMI groups of occupant, delta-V 0-60kmph, two sets (old and new) of car model years. The analysis is carried with three approaches: (a) injury risk percentage based on simple graphical method with respect to a single variable, (b) injury distribution method where the injuries are marked on the respective anatomical locations and (c) logistic regression, a statistical method, considers all the related variables together. Lower extremity injury risk appears to be high for thin BMI group. It is found that BMI does not have much influence on head injuries but it is influenced more by the height of the occupant. Results of logistic analysis suggest that BMI, height and weight may have significant contribution towards side impact injuries across different body regions.

A few seconds to have an accident, a long time to recover: consequences for road accident victims from the ESPARR cohort 2 years after the accident

OBJECTIVE

The aim of the present study was to describe the consequences of a road accident in adults, taking account of the type of road user, and to determine predictive factors for consequences at 2 years.

DESIGN

Prospective follow-up study.

METHODS

The cohort was composed of 1168 victims of road traffic accidents, aged ≥16 years. Two years after the accident, 912 victims completed a self-administered questionnaire. Weighted logistic regression models were implemented to compare casualties still reporting impact related to the accident versus those reporting no residual impact. Five outcomes were analysed: unrecovered health status, impact on occupation or studies, on familial or affective life, on leisure or sport activities and but also the financial difficulties related to the accident.

RESULTS

46.1% of respondents were motorised four-wheel users, 29.6% motorised two-wheel (including quad) users, 13.3% pedestrians (including inline skate and push scooter users) and 11.1% cyclists. 53.3% reported unrecovered health status, 32.0% persisting impact on occupation or studies, 25.2% on familial or affective life, 46.9% on leisure or sport activities and 20.2% still had accident-related financial difficulties. Type of user, adjusted on age and gender, was linked to unrecovered health status and to impact on leisure or sport activities. When global severity (as measured by NISS) was integrated in the previous model, type of user was also associated with impact on occupation or studies. Type of user was further associated with impact on occupation or studies and on leisure or sport activities when global severity and the sociodemographic data obtained at inclusion were taken into account. It was not, however, related to any of the outcomes studied here, when the models focused on the injured body region. Finally, type of road user did not seem, on the various predictive models, to be related to financial difficulties due to the accident or to impact on familial or affective life.

CONCLUSIONS

Overall, victims were affected by their accident even 2 years after it occurred. The severity of lesions induced by the accident was the main predictive factor. However, considering lesion as intermediary factors between the accident and the recovery status at 2 year post-accident, impact on health status was lower for cyclists than M4W users or M2W users.

Correlation Between Euro NCAP Pedestrian Test Results and Injury Severity in Injury Crashes with Pedestrians and Bicyclists in Sweden

Pedestrians and bicyclists account for a significant share of deaths and serious injuries in the road transport system. The protection of pedestrians in car-to-pedestrian crashes has therefore been addressed by friendlier car fronts and since 1997, the European New Car Assessment Program (Euro NCAP) has assessed the level of protection for most car models available in Europe. In the current study, Euro NCAP pedestrian scoring was compared with real-life injury outcomes in car-to-pedestrian and car-tobicyclist crashes occurring in Sweden. Approximately 1200 injured pedestrians and 2000 injured bicyclists were included in the study. Groups of cars with low, medium and high pedestrian scores were compared with respect to pedestrian injury severity on the Maximum Abbreviated Injury Scale (MAIS)-level and risk of permanent medical impairment (RPMI). Significant injury reductions to both pedestrians and bicyclists were found between low and high performing cars. For pedestrians, the reduction of MAIS2+, MAIS3+, RPMI1+ and RPMI10+ ranged from 20-56% and was significant on all levels except for MAIS3+ injuries. Pedestrian head injuries had the highest reduction, 80-90% depending on level of medical impairment. For bicyclist, an injury reduction was only observed between medium and high performing cars. Significant injury reductions were found for all body regions. It was also found that cars fitted with autonomous emergency braking including pedestrian detection might have a 60-70% lower crash involvement than expected. Based on these results, it was recommended that pedestrian protection are implemented on a global scale to provide protection for vulnerable road users worldwide.

Comparing the effects of age, BMI and gender on severe injury (AIS 3+) in motor-vehicle crashes

BACKGROUND

The effects of age, body mass index (BMI) and gender on motor vehicle crash (MVC) injuries are not well understood and current prevention efforts do not effectively address variability in occupant characteristics.

OBJECTIVES

(1) Characterize the effects of age, BMI and gender on serious-to-fatal MVC injury. (2) Identify the crash modes and body regions where the effects of occupant characteristics on the numbers of occupants with injury is largest, and thereby aid in prioritizing the need for human surrogates that represent different types of occupant characteristics and adaptive restraint systems that consider these characteristics.

METHODS

Multivariate logistic regression was used to model the effects of occupant characteristics (age, BMI, gender), vehicle and crash characteristics on serious-to-fatal injuries (AIS 3+) by body region and crash mode using the 2000-2010 National Automotive Sampling System (NASS-CDS) dataset. Logistic regression models were applied to weighted crash data to estimate the change in the number of annual injured occupants with AIS 3+ injury that would occur if occupant characteristics were limited to their 5th percentiles (age≤17 years old, BMI≤19kg/m(2)) or male gender.

RESULTS

Limiting age was associated with a decrease in the total number of occupants with head [8396, 95% CI 6871-9070] and thorax injuries [17,961, 95% CI 15,960-18,859] across all crash modes, decreased occupants with spine [3843, 95% CI 3065-4242] and upper extremity [3578, 95% CI 1402-4439] injuries in frontal and rollover crashes and decreased abdominal [1368, 95% CI 1062-1417] and lower extremity [4584, 95% CI 4012-4995] injuries in frontal impacts. The age effect was modulated by gender with older females more likely to have thorax and upper extremity injuries than older males. Limiting BMI was associated with 2069 [95% CI 1107-2775] fewer thorax injuries in nearside crashes, and 5304 [95% CI 4279-5688] fewer lower extremity injuries in frontal crashes. Setting gender to male resulted in fewer occupants with head injuries in farside crashes [1999, 95% CI 844-2685] and fewer thorax [5618, 95% CI 4212-6272], upper [3804, 95% CI 1781-4803] and lower extremity [2791, 95% CI 2216-3256] injuries in frontal crashes. Results indicate that age provides the greater relative contribution to injury when compared to gender and BMI, especially for thorax and head injuries.

CONCLUSIONS

Restraint systems that account for the differential injury risks associated with age, BMI and gender could have a meaningful effect on injury in motor-vehicle crashes. Computational models of humans that represent older, high BMI, and female occupants are needed for use in simulations of particular types of crashes to develop these restraint systems.

A study of bicyclist kinematics and injuries based on reconstruction of passenger car-bicycle accident in China

Like pedestrians, bicyclists are vulnerable road users, representing a population with a high risk of fatal and severe injuries in traffic accidents as they are unprotected during vehicle collisions. The objective of this study is to investigate the kinematics response of bicyclists and the correlation of the injury severity with vehicle impact speed. Twenty-four car-bicyclist cases with detailed information were selected for accident reconstruction using mathematical models, which was implemented in the MADYMO program. The dynamic response of bicyclists in the typical impact configuration and the correlation of head impact conditions were analyzed and discussed with respect to the head impact speed, time of head impact and impact angle of bicyclists to vehicle impact speed. Furthermore, the injury distribution of bicyclists and the risk of head injuries and fractures of lower limbs were investigated in terms of vehicle impact speed. The results indicate that wrap-around distance (WAD), head impact speed, time of head impact, head impact angle, and throw-out distance (TOD) of the bicyclists have a strong relationship with vehicle impact speed. The vehicle impact speed corresponding to a 50% probability of head AIS 2+ injuries, head AIS 3+ injuries, and lower limb fracture risk for bicyclists is 53.8km/h, 58.9km/h, and 41.2km/h, respectively. A higher vehicle impact speed produces a higher injury risk to bicyclist. The results could provide background knowledge for the establishment or modification of pedestrian regulations considering bicyclist protection as well as being helpful for developing safety measures and protection devices for bicyclists.

Health status recovery at one year in children injured in a road accident: a cohort study

Despite the frequency of traumatic injuries due to road accidents and potential importance of identifying children at risk of impaired recovery one year after a road accident, there is a lack of data on long-term recovery of health status, except in children with severe traumatic brain injury. The aim of the present study was to evaluate predictive factors of recovery in children one year after road traffic injuries. The prospective cohort study was composed of children aged <16 years, admitted to public or private sector hospitals in the Rhône administrative area of France following a road accident. Recovery of health status one year after the accident and information concerning quality of life and the consequences of the accident for the child or family 1 year after the accident were collected by questionnaire, usually completed by the parents. Victims were in majority male (64.6%) and had mild or moderate injuries (81.9% with Maximum Abbreviated Injury Scale (M-AIS) <3). One year after the accident, 75.0% of the mild-to-moderate and 34.8% of the severe cases estimated health status as fully recovered. After adjustment, severity score (M-AIS≥3) and lower limb injury (AIS>1) were associated with incomplete recovery of health status: weighted odds ratio (ORw), 4.3 [95% confidence interval (95% CI), 1.3-14.6] and ORw, 6.5 [95% CI, 1.9-21.7], respectively. Recovery status correlated significantly with quality of life physical scores (r=0.46), especially body pain (r=0.48) and role/social-physical (r=0.50) and, to a lesser extent, quality of life psychosocial scores (r=0.21). In a cohort of children injured in a road accident, those with high injury severity score and those with lower limb injuries are less likely to recover full health status by 1 year. Impaired health status was associated with a lower physical quality of life score at 1 year.

Trauma Whipple: do or don’t after severe pancreaticoduodenal injuries? An analysis of the National Trauma Data Bank (NTDB)

BACKGROUND

Pancreaticoduodenectomy for trauma (PDT) is a rare procedure, reserved for severe pancreaticoduodenal injuries. Using the National Trauma Data Bank (NTDB), our aim was to compare outcomes of PDT patients to similarly injured patients who did not undergo a PDT.

METHODS

Patients with pancreatic or duodenal injuries treated with PDT (ICD-9-CM 52.7) were identified in the NTDB 2008–2010 Research Data Sets. We excluded those who underwent delayed PDT (>4 days). The PDT group (n = 39) was compared to patients with severe combined pancreaticoduodenal injuries (grade 4 or 5) who did not undergo PDT (non-PDT group, n = 38). Patients who died in the emergency department or did not undergo a laparotomy were excluded. Our primary outcome was death. Secondary outcomes were intensive care unit length of stay (LOS), hospital LOS, and total ventilator days. A multivariate model was used to determine predictors of in-hospital mortality within each group and in the overall cohort.

RESULTS

The non-PDT group had a significantly lower systolic blood pressure and Glasgow Coma Scale values at baseline and more severe duodenal, pancreatic, and liver injuries. There were no significant differences in outcomes between the two groups. The Injury Severity Score was the only independent predictor of mortality among PDT patients [odds ratio (OR) 1.12, 95 % confidence interval (CI) 1.01–1.24] and in the entire cohort (OR 1.06, 95 % CI 1.01–1.12). The operative technique did not influence any of the outcomes.

CONCLUSIONS

Compared to non-PDT, PDT did not result in improved outcomes despite a lower physiologic burden among PDT patients. More conservative procedures for high-grade injuries of the pancreaticoduodenal complex may be appropriate.

Safety of the Japanese K-car in a real-world low-severity frontal collision

OBJECTIVE

Kei-cars (K-cars), which are a tiny 660 cc mini-car class 3.4 m long or less, 1.48 m wide or less, and 2.00 m high or less, have become popular in Japan. To evaluate the safety of K-car drivers in frontal collisions, we retrospectively compared the severity of injuries suffered by drivers between K-cars and standard vehicles involved in frontal collisions in which at least one injury occurred.

MATERIALS AND METHODS

From in-depth data provided by the Institute for Traffic Accident Research and Data Analysis from 1993 to 2010, records for 1379 drivers aged 36.8 ± 15.6 years were collected for analysis.

RESULTS

Of the 1379 drivers, 1115 subjects were in standard vehicles and 264 were in K-cars. The mean delta V of the struck vehicle was 28.6 ± 15.6 km/h. After classifying the subjects according to seat belt use and air bag deployment, the background of the drivers and delta V, the injury severity scores (ISSs) and Abbreviated Injury Scale (AIS) scores were compared for all body regions. Under similar conditions, no significant differences in severity of injuries of the drivers were found between K-cars and standard vehicles.

CONCLUSIONS

Although we are generally concerned that drivers of small vehicles suffer more severe injuries, our results suggest that, for real-world accidents, K-cars provide similar safety for drivers involved in frontal collisions as standard vehicles in low delta V impact conditions.

[Measuring trauma severity using the 1998 and 2005 revisions of the abbreviated injury scale]

OBJECTIVES

This study aims to compare injury and trauma severity as measured by the 1998 and 2005 revisions of the Abbreviated Injury Sca le and to determine the mortality in the Injury Severity Score and the New Injury Severity Score in both versions.

METHOD

This cross-sectional retrospective study analyzed injuries of trauma patients from three university hospitals in Sao Paulo, Brazil. Each injury was coded using the Abbreviated Injury Scale 1998 and 2005. The statistical tests applied were the Wilcoxon, McNemar-Bowker, Kappa, and Z tests.

RESULTS

Comparing the two versions resulted in significant disagreement regard ing the scores of certain body regions. With the 2005 version, injury and trauma severity levels were significantly decreased, and the mortality was higher at lower scores.

CONCLUSION

Injury and trauma severity were decreased and the percentage mortality was changed when the 2005 revision of the Abbreviated Injury Scale was used.

Vertebral fractures in motor vehicle accidents - a medical and technical analysis of 33,015 injured front-seat occupants

Spinal injuries pose a considerable risk to life and quality of life. In spite of improvements in active and passive safety of motor vehicles, car accidents are regarded as a major cause for vertebral fractures. The purpose of this study was to evaluate the current incidence of vertebral fractures among front-seat occupants in motor vehicle accidents, and to identify specific risk factors for sustaining vertebral fractures in motor vehicle accidents. Data from an accident research unit were accessed to collect collision details, preclinical data, and clinical data. We included all data on front-seat occupants. Hospital records were retrieved, and radiological images were evaluated. We analysed 33,015 front-seat occupants involved in motor vehicle accidents over a 24-year period. We identified 126 subjects (0.38%) with cervical spine fractures, 78 (0.24%) with thoracic fractures, and 99 (0.30%) with lumbar fractures. The mean relative collision speeds were 48, 39, and 40 kph in subjects with cervical, thoracic, and lumbar spine fractures, respectively, while it was 17.3 kph in the whole cohort. Contrary to the overall cohort, these patients typically sustained multiple hits rather than simple front collisions. Occupants with vertebral fractures frequently showed numerous concomitant injuries; for example, additional vertebral fractures. The incidence of vertebral fractures corresponded with collision speed. Safety belts were highly effective in the prevention of vertebral fractures. Apart from high speed, complex injury mechanisms as multiple collisions or rollovers were associated with vertebral fractures. Additional preventive measures should focus on these collision mechanisms.

Standardisierte Bewertung von Unfallverletzten: Anforderungen an die bildgebende Diagnostik

INTRODUCTION

Evaluation of trauma systems requires a complete and exact injury classification. The purpose of this study was the introduction of the Abbreviated injury scale (AIS) for radiological trauma scoring. The development of these easy to use coding tools is essential for prompt quality management of trauma.

MATERIAL AND METHODS

Standardized radiological injury description using a modified Abbreviated injury scale in combination with a Microsoft Excel spreadsheet allows an immediate calculation of the probability of survival according to TRISS methodology.

RESULTS

Computed tomography is the main instrument for injury scoring in trauma care. Postmortem scanning provides a direct feedback for trauma teams especially in case when autopsy is not possible.

CONCLUSION

Computed tomography enables in combination with a standardized injury description exact trauma scoring. Quality management of trauma care depends on a valid and reliable calculation of the probability of survival using TRISS.

To TQIP or not to TQIP? That is the question

The Trauma Quality Improvement Program (TQIP) reports a feasible mortality prediction model. We hypothesize that our institutional characteristics differ from TQIP aggregate data, questioning its applicability. We conducted a 2-year (2008 to 2009) retrospective analysis of all trauma activations at a Level 1 trauma center. Data were analyzed using TQIP methodology (three groups: blunt single system, blunt multisystem, and penetrating) to develop a mortality prediction model using multiple logistic regression. These data were compared with TQIP data. Four hundred fifty-seven patients met TQIP inclusion criteria. Penetrating and blunt trauma differed significantly at our institution versus TQIP aggregates (61.9 vs 7.8%; 38.0 vs 92.2%, P < 0.01). There were more firearm mechanisms of injury and less falls compared with TQIP aggregates (28.9 vs 4.2%; 8.5 vs 34.8%, P < 0.01). All other mechanisms were not significantly different. Variables significant in the TQIP model but not found to be predictors of mortality included Glasgow Coma Score motor 2 to 5, systolic blood pressure greater than 90 mmHg, age, initial pulse rate in the emergency department, mechanism of injury, head Abbreviated Injury Score, and abdominal Abbreviated Injury Score. External benchmarking of trauma center performance using mortality prediction models is important in quality improvement for trauma patient care. From our results, TQIP methodology from the pilot study may not be applicable to all institutions.

Injury prediction in a side impact crash using human body model simulation

BACKGROUND

Improved understanding of the occupant loading conditions in real world crashes is critical for injury prevention and new vehicle design. The purpose of this study was to develop a robust methodology to reconstruct injuries sustained in real world crashes using vehicle and human body finite element models.

METHODS

A real world near-side impact crash was selected from the Crash Injury Research and Engineering Network (CIREN) database. An average sedan was struck at approximately the B-pillar with a 290 degree principal direction of force by a lightweight pickup truck, resulting in a maximum crush of 45 cm and a crash reconstruction derived Delta-V of 28 kph. The belted 73-year-old midsized female driver sustained severe thoracic injuries, serious brain injuries, moderate abdominal injuries, and no pelvic injury. Vehicle finite element models were selected to reconstruct the crash. The bullet vehicle parameters were heuristically optimized to match the crush profile of the simulated struck vehicle and the case vehicle. The Total Human Model for Safety (THUMS) midsized male finite element model of the human body was used to represent the case occupant and reconstruct her injuries using the head injury criterion (HIC), half deflection, thoracic trauma index (TTI), and pelvic force to predict injury risk. A variation study was conducted to evaluate the robustness of the injury predictions by varying the bullet vehicle parameters.

RESULTS

The THUMS thoracic injury metrics resulted in a calculated risk exceeding 90% for AIS3+ injuries and 70% risk of AIS4+ injuries, consistent with her thoracic injury outcome. The THUMS model predicted seven rib fractures compared to the case occupant's 11 rib fractures, which are both AIS3 injuries. The pelvic injury risk for AIS2+ and AIS3+ injuries were 37% and 2.6%, respectively, consistent with the absence of pelvic injury. The THUMS injury prediction metrics were most sensitive to bullet vehicle location. The maximum 95% confidence interval width for the mean injury metrics was only 5% demonstrating high confidence in the THUMS injury prediction.

CONCLUSIONS

This study demonstrates a variation study methodology in which human body models can be reliably used to robustly predict injury probability consistent with real world crash injury outcome.

Light-vehicle occupancy and severe injury by vehicle and crash type

PURPOSE

This study investigated the number of occupants involved and severely injured in light-vehicle crashes by vehicle and crash type.

METHODS

1994-2010 NASS-CDS data were analyzed to estimate the risk of severely injured occupants involved in motor vehicle crashes. Crashes were grouped by front, side, rear, and rollovers. The effect of occupancy and vehicle type was investigated. Light vehicles were less than 4536 kg with model year 1994+. The annual number of Maximum Abbreviated Injury Scale (MAIS) 4+F injuries was estimated and the risk was determined using all occupants with known injury (MAIS 0-6+F).

RESULTS

There were 21,869 MAIS 4+F injuries annually, with 62.7 percent involving passenger cars, 15.9 percent sport utility vehicles (SUVs), 15.3 percent trucks, and 6.1 percent vans. In 36.6 percent of van crashes, MAIS 4+F occurred when there were 4+ occupants and 13.0 percent with 7+ occupants in the vehicle. Overall, 12.8 percent of severely injured were in crashes involving 4+ occupants and 1.4 percent with 7+ occupants. In addition, 30.1 percent of MAIS 4+F occurred in rollovers and only 5.8 percent of crashes were rollovers. Rollovers had the highest injury risks, irrespective of the number of occupants. There was a trend for an increased fraction of injury in frontal crashes and a lower fraction in rollovers. There were high risks in side and rear crashes with 5+ occupants.

CONCLUSIONS

On average, there were 1.35 occupants involved in a crash per vehicle. Severely injured occupants were uncommon in 5+ occupancy vehicles. There was a trend for increased injury risks with occupancy. The risk was 1.65 times higher in vehicles with 7+ occupants compared to those with a driver only.

A comparison of KABCO and AIS injury severity metrics using CODES linked data

OBJECTIVE

The research objective is to compare the consistency of distributions between crash assigned (KABCO) and hospital assigned (Abbreviated Injury Scale, AIS) injury severity scoring systems for 2 states. The hypothesis is that AIS scores will be more consistent between the 2 studied states (Maryland and Utah) than KABCO.

METHODS

The analysis involved Crash Outcome Data Evaluation System (CODES) data from 2 states, Maryland and Utah, for years 2006-2008. Crash report and hospital inpatient data were linked probabilistically and International Classification of Diseases (CMS 2013) codes from hospital records were translated into AIS codes. KABCO scores from police crash reports were compared to those AIS scores within and between the 2 study states.

RESULTS

Maryland appears to have the more severe crash report KABCO scoring for injured crash participants, with close to 50 percent of all injured persons being coded as a level B or worse, and Utah observes approximately 40 percent in this group. When analyzing AIS scores, some fluctuation was seen within states over time, but the distribution of MAIS is much more comparable between states. Maryland had approximately 85 percent of hospitalized injured cases coded as MAIS = 1 or minor. In Utah this percentage was close to 80 percent for all 3 years. This is quite different from the KABCO distributions, where Maryland had a smaller percentage of cases in the lowest injury severity category as compared to Utah.

CONCLUSIONS

This analysis examines the distribution of 2 injury severity metrics different in both design and collection and found that both classifications are consistent within each state from 2006 to 2008. However, the distribution of both KABCO and Maximum Abbreviated Injury Scale (MAIS) varies between the states. MAIS was found to be more consistent between states than KABCO.

A real-life based evaluation method of deployable vulnerable road user protection systems

OBJECTIVE

The aim of this study was to develop a real-life-based evaluation method, incorporating vulnerable road user (VRU) full-body loading to a vehicle with a deployable protection system in relevant test setups, and use this method to evaluate a prototype pedestrian and cyclist protection system.

METHODS

Based on accident data from severe crashes, the most common scenarios were selected and developed into 5 test setups, 2 for pedestrians and 3 for bicyclists. The Polar II pedestrian anthropomorphic test device was used, either standing or on a standard bicycle. These test setups could then be used to evaluate real-life performance of a prototype protection system, regarding both positioning and protection, for vulnerable road users. The protection system consisted of an active hood and a windshield airbag and was mounted on a large passenger car with a conventional hood-type front end. Injury evaluation criteria were selected for head, neck, and chest loading derived from occupant frontal and side impact test methods.

RESULTS

The protection system managed to be fully deployed, obtaining the intended position in time-that is, before VRU body contact-in all test setups, and head protection potential was not negatively influenced by the preceding thoracic impact. Head loading resulted in head injury criterion (HIC) values ranging up to 4400 for the standard car, and all HIC values were below 650 with the protection system. The risk of severe (Abbreviated Injury Scale [AIS] 3+) head injury decreased from 85% to 100% in 3 test setups (mainly to the windscreen frame), to less than a 20% risk in all setups. In general, there were larger differences between structures impacted than between the pedestrian and cyclist setup. Neck loading was maintained at an acceptable level or was slightly decreased by the protection system, and chest loading was decreased from high values in 2 test setups in which the cyclist was impacted laterally with chest impact mainly to the hood area.

CONCLUSIONS

A test method was developed to evaluate a more real-life-based test condition, as a complement to current component test methods. Being real-life based, including full-body loading, it is suggested as a complementary test method to the more simplified legal and rating component tests. Together these test methods will provide a more thorough evaluation of a protection system. The evaluated protection system performed well regarding both positioning and protection, indicating a capability to obtain the intended position in time with the potential to prevent the most common severe upper-body injuries of a pedestrian or cyclist in typical real-life accidents, without introducing negative side effects.

Predicting work-related disability and medical cost outcomes: a comparison of injury severity scoring methods

INTRODUCTION

Acute work-related trauma is a leading cause of death and disability among U.S. workers. Occupational health services researchers have described the pressing need to identify valid injury severity measures for purposes such as case-mix adjustment and the construction of appropriate comparison groups in programme evaluation, intervention, quality improvement, and outcome studies. The objective of this study was to compare the performance of several injury severity scores and scoring methods in the context of predicting work-related disability and medical cost outcomes.

METHODS

Washington State Trauma Registry (WTR) records for injuries treated from 1998 to 2008 were linked with workers' compensation claims. Several Abbreviated Injury Scale (AIS)-based injury severity measures (ISS, New ISS, maximum AIS) were estimated directly from ICD-9-CM codes using two software packages: (1) ICDMAP-90, and (2) Stata's user-written ICDPIC programme (ICDPIC). ICDMAP-90 and ICDPIC scores were compared with existing WTR scores using the Akaike Information Criterion, amount of variance explained, and estimated effects on outcomes. Competing risks survival analysis was used to evaluate work disability outcomes. Adjusted total medical costs were modelled using linear regression.

RESULTS

The linked sample contained 6052 work-related injury events. There was substantial agreement between WTR scores and those estimated by ICDMAP-90 (kappa=0.73), and between WTR scores and those estimated by ICDPIC (kappa=0.68). Work disability and medical costs increased monotonically with injury severity, and injury severity was a significant predictor of work disability and medical cost outcomes in all models. WTR and ICDMAP-90 scores performed better with regard to predicting outcomes than did ICDPIC scores, but effect estimates were similar. Of the three severity measures, maxAIS was usually weakest, except when predicting total permanent disability.

CONCLUSIONS

Injury severity was significantly associated with work disability and medical cost outcomes for work-related injuries. Injury severity can be estimated using either ICDMAP-90 or ICDPIC when ICD-9-CM codes are available. We observed little practical difference between severity measures or scoring methods. This study demonstrated that using existing software to estimate injury severity may be useful to enhance occupational injury surveillance and research.

Detecting active pelvic arterial haemorrhage on admission following serious pelvic fracture in multiple trauma patients

BACKGROUND

The early diagnosis of pelvic arterial haemorrhage is challenging for initiating treatment by transcatheter arterial embolization (TAE) in multiple trauma patients. We use an institutional algorithm focusing on haemodynamic status on admission and on a whole-body CT scan in stabilized patients to screen patients requiring TAE. This study aimed to assess the effectiveness of this approach.

METHODS

This retrospective cohort study included 106 multiple trauma patients admitted to the emergency room with serious pelvic fracture [pelvic abbreviated injury scale (AIS) score of 3 or more].

RESULTS

Of the 106 patients, 27 (25%) underwent pelvic angiography leading to TAE for active arterial haemorrhage in 24. The TAE procedure was successful within 3h of arrival in 18 patients. In accordance with the algorithm, 10 patients were directly admitted to the angiography unit (n=8) and/or operating room (n=2) for uncontrolled haemorrhagic shock on admission. Of the remaining 96 stabilized patients, 20 had contrast media extravasation on pelvic CT scan that prompted pelvic angiography in 16 patients leading to TAE in 14. One patient underwent a pelvic angiography despite showing no contrast media extravasation on pelvic CT scan. All 17 stabilized patients who underwent pelvic angiography presented a more severely compromised haemodynamic status on admission, and they required more blood products during their initial management than the 79 patients who did not undergo pelvic angiography. The incidence of unstable pelvic fractures was however comparable between the two groups. Overall, haemodynamic instability and contrast media extravasation on the CT-scan identified 26 out of the 27 patients who required subsequent pelvic angiography leading to TAE in 24.

CONCLUSIONS

An algorithm focusing on haemodynamic status on arrival and on the whole-body CT scan in stabilized patients may be effective at triaging multiple trauma patients with serious pelvic fractures.

The benefits and tradeoffs for varied high-severity injury risk thresholds for advanced automatic crash notification systems

OBJECTIVES

The objectives of this study are to (1) characterize the population of crashes meeting the Centers for Disease Control and Prevention (CDC)-recommended 20% risk of Injury Severity Score (ISS)>15 injury and (2) explore the positive and negative effects of an advanced automatic crash notification (AACN) system whose threshold for high-risk indications is 10% versus 20%.

METHODS

Binary logistic regression analysis was performed to predict the occurrence of motor vehicle crash injuries at both the ISS>15 and Maximum Abbreviated Injury Scale (MAIS) 3+ level. Models were trained using crash characteristics recommended by the CDC Committee on Advanced Automatic Collision Notification and Triage of the Injured Patient. Each model was used to assign the probability of severe injury (defined as MAIS 3+ or ISS>15 injury) to a subset of NASS-CDS cases based on crash attributes. Subsequently, actual AIS and ISS levels were compared with the predicted probability of injury to determine the extent to which the seriously injured had corresponding probabilities exceeding the 10% and 20% risk thresholds. Models were developed using an 80% sample of NASS-CDS data from 2002 to 2012 and evaluations were performed using the remaining 20% of cases from the same period.

RESULTS

Within the population of seriously injured (i.e., those having one or more AIS 3 or higher injuries), the number of occupants whose injury risk did not exceed the 10% and 20% thresholds were estimated to be 11,700 and 18,600, respectively, each year using the MAIS 3+ injury model. For the ISS>15 model, 8,100 and 11,000 occupants sustained ISS>15 injuries yet their injury probability did not reach the 10% and 20% probability for severe injury respectively. Conversely, model predictions suggested that, at the 10% and 20% thresholds, 207,700 and 55,400 drivers respectively would be incorrectly flagged as injured when their injuries had not reached the AIS 3 level. For the ISS>15 model, 87,300 and 41,900 drivers would be incorrectly flagged as injured when injury severity had not reached the ISS>15 injury level.

CONCLUSIONS

This article provides important information comparing the expected positive and negative effects of an AACN system with thresholds at the 10% and 20% levels using 2 outcome metrics. Overall, results suggest that the 20% risk threshold would not provide a useful notification to improve the quality of care for a large number of seriously injured crash victims. Alternately, a lower threshold may increase the over triage rate. Based on the vehicle damage observed for crashes reaching and exceeding the 10% risk threshold, we anticipate that rescue services would have been deployed based on current Public Safety Answering Point (PSAP) practices.

Evaluation of near-side oblique frontal impacts using THOR with SD3 shoulder

OBJECTIVE

Within the EC Seventh Framework project THORAX, the Mod-Kit THOR was upgraded with a new thorax and shoulder. The aim of this study was to investigate whether the THOR ATD met a set of prerequisites to a greater extent than Hybrid III and by that measure whether the dummy could serve as a potential tool for future evaluation of serious head and chest injuries in near-side oblique frontal impacts.

METHOD

A small-overlap/oblique sled system was used to reflect occupant forces observed in oblique frontal crashes. The head and thoracic response from THOR was evaluated for 3 combinations: belt only with no deformation of the driver's side door (configuration A), belt only in combination with a predeformed door (configuration B), and prepretensioning belt and driver airbag (PPT+DAB) in combination with a predeformed door (configuration C). To evaluate head injury risk, the head injury criterion (HIC) and brain injury criteria (BrIC) were used. For evaluation of the thoracic injury risk, 3 injury criteria proposed by the THORAX project were evaluated: Dmax, DcTHOR, and strain (dummy rib fractures).

RESULTS

Unlike Hybrid III, the THOR with SD3 shoulder interacted with the side structure in a near-side oblique frontal impact. HIC values for the 3 test configurations corresponded to a 90% (A) and 100% (B and C) risk of Abbreviated Injury Scale (AIS) 2+ head injury, and BrIC values resulted in a 100% risk of AIS 2+ head injury in configurations A and B. In C the risk was reduced to 75%. The AIS 2+ thoracic injury risks based on Dmax were similar (14-18%) for all tests. Based on DcTHOR, AIS 2+ injury risk increased from 29 to 53% as the predeformed door side was introduced (A to B), and the risk increased, to 64%, as a PPT+DAB was added (C). Considering the AIS 2+ injury risk based on strain, tests in A resulted in an average of 3 dummy rib fractures (17%). Introducing the predeformed door (B) increased the average of dummy fractures to 5 (39%), but in C the average number of dummy rib fractures decreased to 4 (28%).

CONCLUSIONS

THOR with an SD3 shoulder should be the preferred ATD rather than the Hybrid III for evaluating head and thorax injuries in oblique frontal impacts. Thoracic interaction with the predeformed door was not well captured by the 3D IR-Traccs; hence, use of deflection as an injury predictor in oblique loading is insufficient for evaluating injury risk in this load case. However, injury risk evaluation may be performed using the strain measurements, which characterize loading from seat belt and airbag as well as the lateral contribution of the structural impact in the loading condition used in this study.

Factors that influence chest injuries in rollovers

OBJECTIVES

The design of countermeasures to reduce serious chest injuries for belted occupants involved in rollover crashes requires an understanding of the cause of these injuries and of the test conditions to assure the effectiveness of the countermeasures. This study defines rollover environments and occupant-to-vehicle interactions that cause chest injuries for belted drivers.

METHODS

The NASS-CDS was examined to determine the frequency and crash severity for belted drivers with serious (Abbreviated Injury Scale [AIS] 3+) chest injuries in rollovers. Case studies of NASS crashes with serious chest injuries sustained by belted front occupants were undertaken and damage patterns were determined. Vehicle rollover tests with dummies were examined to determine occupant motion in crashes with damage similar to that observed in the NASS cases. Computer simulations were performed to further explore factors that could contribute to chest injury. Finite element model (FEM) vehicle models with both the FEM Hybrid III dummy and THUMS human model were used in the simulations.

RESULTS

Simulation of rollovers with 6 quarter-turns or less indicated that increases in the vehicle pitch, either positive or negative, increased the severity of dummy chest loadings. This finding was consistent with vehicle damage observations from NASS cases. For the far-side occupant, the maximum chest loadings were caused by belt and side interactions during the third quarter-turn and by the center console loading during the fourth quarter-turn. The results showed that the THUMS dummy produced more realistic kinematics and improved insights into skeletal and chest organ loadings compared to the Hybrid III dummy.

CONCLUSIONS

These results suggest that a dynamic rollover test to encourage chest injury reduction countermeasures should induce a roll of at least 4 quarter-turns and should also include initial vehicle pitch and/or yaw so that the vehicle's axis of rotation is not aligned with its inertial roll axis during the initial stage of the rollover.

Optimising the management of severe Traumatic Brain Injury in the military maritime environment

Severe Traumatic Brain Injury (sTBI) is a devastating cause of morbidity and mortality, especially among those aged less than 45 years. Advances in clinical practice continue to focus on preventing primary injury through developing ballistic head and eye protection, and through minimising secondary brain injury (secondary prevention). Managing sTBI is challenging in well-developed, well-resourced healthcare systems. Achieving management aims in the military maritime environment poses even greater challenges. Strategies for the management of sTBI in the maritime environment should be in keeping with current best evidence. Provision of specialist interventions for sTBI in military maritime environments may require alternative approaches matched to the skills of the staff and environmental restrictions.

Long-term medical consequences for child occupants 0 to 12 years injured in car crashes

OBJECTIVE

There is limited knowledge of the long-term medical consequences for children injured in car crashes. Thus, in the event of injury, the aim of the study was to specify patterns and risks of injuries resulting in permanent medical impairment of children (0-12 years) for different body regions and injury severity levels, according to Abbreviated Injury Scale (AIS). The aim was also to compare the impairment outcome with adults.

METHODS

Data were obtained from the Folksam insurance company, including reported car crashes from 1998 to 2010 with at least one injured child 0-12 years of age. In all, 2619 injured children with 3704 reported medical diagnoses were identified. All injuries were classified according to the AIS 2005 revision. If the child had not recovered within 1 year postinjury an assessment of permanent medical impairment (PMI) was made by one or several medical specialists.

RESULTS

In all, 55 children sustained 59 injuries resulting in PMI of which 75 percent were at AIS 1 or AIS 2. The head and cervical spine were the body regions sustaining the most injuries resulting in PMI. Sixty-eight percent of all injuries resulting in PMI were AIS 1 injuries to the cervical spine, with the majority occurring in frontal or rear impacts. Given an injury to the cervical spine, the risk of injuries resulting in PMI was 3 percent, and older children (≥6 years) had a significantly higher risk (3% versus 1%) than younger children. The head was the second most commonly injured body region with injuries resulting in PMI (12/59), which were predominantly AIS 2+. In addition, mild traumatic brain injuries at AIS 1 were found to lead to PMI. Whereas for children the injuries leading to PMI were primarily limited to the head and cervical spine, adults sustained injuries that led to PMI from a more diverse distribution of body regions.

CONCLUSION

The pattern of injuries resulting in permanent medical impairment is different for children and adults; therefore, safety priorities for children need to be based on child data. The majority of those injuries leading to PMI were at lower AIS levels. Furthermore, AIS 1 cervical spine and AIS 1+ head injuries should be given priority concerning mitigation of long-term consequences for children.

The impact of traumatic pelvic fractures on sporting activity and quality of life

BACKGROUND

Pelvic fractures (PFX) reflect high-energy trauma with high mortality and morbidity.

AIM

We attempted to determine: whether there is a decrease in levels of sporting and physical activity in patients with operatively-treated PFX; risk factors for decreased sporting activity; any correlation between sporting activity and quality of life in this group.

METHODS

Retrospective demographics on mechanism of injury, fracture type, associated injury and injury severity score, as well as prospective documentation of the level and frequency of sporting activity, were collected from adult patients treated operatively for a PFX between 2007 and 2010, using a specifically designed questionnaire. Quality of life before and after injury was also recorded using the EuroQol-5D health-outcome tool.

RESULTS

80 patients without pre-existing musculoskeletal disability were enrolled. The mean age was 44.9 years (18-65). The mean follow-up was 30.5 months (12-39). A decrease in level and frequency of sporting activity was observed. It was associated with lower-extremity associated injuries, but not with injury severity score, PFX severity, PFX type, age, or timing of follow-up. Sporting activity before injury predicted higher levels of sporting participation after injury. Decreased sporting activity after injury was associated with decreased EuroQol-SD score.

CONCLUSIONS

Patients should be counselled on the likelihood of a reduction in sporting activities after surgically treated PFX. A larger multi-centre study is needed to further expand on the evidence of the true impact of PFX and its associated injuries on sporting activity.

Motor vehicle crash-related injury causation scenarios for spinal injuries in restrained children and adolescents

OBJECTIVE

Motor vehicle crash (MVC)-related spinal injuries result in significant morbidity and mortality in children. The objective was to identify MVC-related injury causation scenarios for spinal injuries in restrained children.

METHODS

This was a case series of occupants in MVCs from the Crash Injury Research and Engineering Network (CIREN) data set. Occupants aged 0-17 years old with at least one Abbreviated Injury Scale (AIS) 2+ severity spinal injury in vehicles model year 1990+ that did not experience a rollover were included. Unrestrained occupants, those not using the shoulder portion of the belt restraint, and those with child restraint gross misuse were excluded. Occupants with preexisting comorbidities contributing to spinal injury and occupants with limited injury information were also excluded. A multidisciplinary team retrospectively reviewed each case to determine injury causation scenarios (ICSs). Crash conditions, occupant and restraint characteristics, and injuries were qualitatively summarized.

RESULTS

Fifty-nine cases met the study inclusion criteria and 17 were excluded. The 42 occupants included sustained 97 distinct AIS 2+ spinal injuries (27 cervical, 22 thoracic, and 48 lumbar; 80 AIS-2, 15 AIS-3, 1 AIS-5, and 1 AIS-6), with fracture as the most common injury type (80%). Spinal-injured occupants were most frequently in passenger cars (64%), and crash direction was most often frontal (62%). Mean delta-V was 51.3 km/h±19.4 km/h. The average occupant age was 12.4±5.3 years old, and 48% were 16- to 17-year-olds. Thirty-six percent were right front passengers and 26% were drivers. Most occupants were lap and shoulder belt restrained (88%). Non-spinal AIS 2+ injuries included those of the lower extremity and pelvis (n=56), head (n=43), abdomen (n=39), and thorax (n=36). Spinal injury causation was typically due to flexion or lateral bending over the lap and or shoulder belt or child restraint harness, compression by occupant's own seat back, or axial loading through the seat pan. Nearly all injuries in children<12 years occurred by flexion over a restraint, whereas teenage passengers had flexion, direct contact, and other ICS mechanisms. All of the occupants with frontal flexion mechanism had injuries to the lumbar spine, and most (78%) had associated hollow or solid organ abdominal injuries.

CONCLUSIONS

Restrained children in nonrollover MVCs with spinal injuries in the CIREN database are most frequently in high-speed frontal crashes, of teenage age, and have vertebral fractures. There are age-specific mechanism patterns that should be further explored. Because even moderate spinal trauma can result in measurable morbidity, future efforts should focus on mitigating these injuries.

Crash characteristics and injury patterns of restrained front seat occupants in far-side impacts

OBJECTIVE

The study was conducted to determine the association between vehicle-, crash-, and demographic-related factors and injuries to front seat far-side occupants in modern environments.

METHODS

Field data were obtained from the NASS-CDS database for the years 2009-2012. Inclusion factors included the following: adult restrained front outboard-seated occupants, no ejection or rollovers, and vehicle model years less than 10 years old at the time of crash. Far-side crashes were determined by using collision deformation classification. Injuries were scored using the Abbreviated Injury Scale (AIS). Injuries (MAIS 2+, MAIS 3+, M denotes maximum score) were examined based on demographics, change in velocity, vehicle type, direction of force, extent zone, collision partner, and presence of another occupant in the front seat. Only weighted data were used in the analysis. Injuries to the head and face, thorax, abdomen, pelvis, and upper and lower extremity regions were studied. Odds ratios and upper and lower confidence intervals were estimated from multivariate analysis.

RESULTS

Out of 519,195 far-side occupants, 17,715 were MAIS 2+ and 4,387 were MAIS 3+ level injured occupants. The mean age, stature, total body mass, and body mass index (BMI) were 40.7 years, 1.7 m, 77.2 kg, and 26.8 kg/m2, respectively. Of occupants with MAIS 2+ injuries, 51% had head and 19% had thorax injuries. Of occupants with MAIS 3+ injuries, 50% had head and 69% had thorax injuries. The cumulative distribution of changes in velocities at the 50th percentile for the struck vehicle for all occupants and occupants with MAIS 2+ and MAIS 3+ injuries were 19, 34, and 42 km/h, respectively. Furthermore, 73% of MAIS 2+ injuries and 86% of MAIS 3+ injuries occurred at a change in velocity of 24 km/h or greater. Odds of sustaining MAIS 2+ and MAIS 3+ injuries increased with each unit increase in change in velocity, stature, and age, with one exception. Odds of sustaining injuries were higher with the presence of an occupant in the front seat at the MAIS 3+ level, although it was reversed at the lower level. The extent zone of 3+ increased the odds compared to the extent zones of 1 to 2 at both MAIS 2+ and MAIS 3+ injuries. Odds ratios and confidence intervals are given.

CONCLUSIONS

The findings are as follows: head and thorax are the more frequently injured body regions, and the prevalence of cranium injuries is similar at both injury severities; thoracic injuries are more prevalent at the MAIS 3+ level; the presence of another front seat occupant plays a role in MAIS 3+ trauma; injuries continue to occur at changes in velocity representative of side impact environments; and mean demographic factors are close to mid-size automotive anthropometry, indicating the need to pursue this line of study. Because data were gathered from only 4 years, it would be important to include additional NASS-CDS database years, rescore injuries from previous years, and analyze other international databases to reinforce these findings for advancing safety for far-side occupants.

Developing a burn injury severity score (BISS): adding age and total body surface area burned to the injury severity score (ISS) improves mortality concordance

BACKGROUND

There is limited research validating the injury severity score (ISS) in burns. We examined the concordance of ISS with burn mortality. We hypothesized that combining age and total body surface area (TBSA) burned to the ISS gives a more accurate mortality risk estimate.

METHODS

Data from the Royal Perth Hospital Trauma Registry and the Royal Perth Hospital Burns Minimum Data Set were linked. Area under the receiver operating characteristic curve (AUC) measured concordance of ISS with mortality. Using logistic regression models with death as the dependent variable we developed a burn-specific injury severity score (BISS).

RESULTS

There were 1344 burns with 24 (1.8%) deaths, median TBSA 5% (IQR 2-10), and median age 36 years (IQR 23-50). The results show ISS is a good predictor of death for burns when ISS≤15 (OR 1.29, p=0.02), but not for ISS>15 (ISS 16-24: OR 1.09, p=0.81; ISS 25-49: OR 0.81, p=0.19). Comparing the AUCs adjusted for age, gender and cause, ISS of 84% (95% CI 82-85%) and BISS of 95% (95% CI 92-98%), demonstrated superior performance of BISS as a mortality predictor for burns.

CONCLUSION

ISS is a poor predictor of death in severe burns. The BISS combines ISS with age and TBSA and performs significantly better than the ISS.

The quantification of liver anatomical changes and assessment of occupant liver injury patterns

Liver injuries can be significant in vehicle crashes. In this study, the liver anatomy was quantified in both adult and pediatric populations as a function of gender and age. Five anatomical liver measurements were determined using CT scans of 260 normal livers. These measurements include the area and volume, and the length, width, and girth of the liver (IRB HUM00041441). To characterize geometrical shape, an inscribed sphere and circumscribed ellipsoid were fitted on the measurements. In the pediatric population the liver area and volume continuously increased with age. When normalized by patient weight, volume measurements show a decrease in volume with age, suggesting that the liver occupies a smaller proportion of the body with age. In the adult population, liver measurements varied with gender. The superior and inferior locations of the liver were also recorded with respect to the spine. The lower portion was at the L3 in small children and at L2 as children approached puberty. It stayed in that area through the 60+ group, offering more ribcage protection. Liver injury patterns were also assessed in crash occupants. Seventy-two occupants with moderate to severe (AIS 2+) liver injuries were investigated. A new methodology was presented and consisted of quantifying blood volumes. The results were compared to overall liver volume and injury scales. No clear distinction on the injury pattern was observed by age group. Liver injuries were more commonly associated with AIS 2+ thoracic injuries in adults than in children. Most injuries occurred in the right lobe.

Assessing injury severity in bicyclists involved in traffic accidents to more effectively prevent fatal bicycle injuries in Japan

The objective of this study was to clarify the relationship between injury severity in bicyclists involved in traffic accidents and patient outcome or type of vehicle involved in order to propose effective measures to prevent fatal bicycle injuries. Hospital records were reviewed for all patients from 2007 to 2010 who had been involved in a traffic accident while riding a bicycle and were subsequently transferred to the Shock Trauma Center of Dokkyo Medical University Koshigaya Hospital. Patient outcomes and type of vehicle that caused the injury were examined. The mechanism of injury, Abbreviated Injury Scale (AIS) score, and Injury Severity Score (ISS) of the patient were determined. A total of 115 patients' records were reviewed. The mean patient age was 47.1 ± 27.4 years. The average ISS was 23.9, with an average maximum AIS (MAIS) score of 3.7. The ISS, MAIS score, head AIS score, and chest AIS score were well correlated with patient outcome. The head AIS score was significantly higher in patients who had died (mean of 4.4); however, the ISS, MAIS score, and head AIS score did not differ significantly according to the type of vehicle involved in the accident. The mean head AIS scores were as high as 2.4 or more for accidents involving any type of vehicle. This study provides useful information for forensic pathologists who suspect head injuries in bicyclists involved in traffic accidents. To effectively reduce bicyclist fatalities from traffic accidents, helmet use should be required for all bicyclists.

Observational study of child restraining practice on Norwegian high-speed roads: restraint misuse poses a major threat to child passenger safety

OBJECTIVE

Restraint misuse and other occupant safety errors are the major cause of fatal and, severe injuries among child passengers in motor vehicle collisions. The main objectives of the present, study were to provide estimates of restraining practice among children younger than 16 years, traveling on Norwegian high-speed roads, and to uncover the high-risk groups associated with, restraint misuse and other safety errors.

METHODS

A cross-sectional observational study was performed in conjunction with regular traffic, control posts on high-speed roads. The seating and restraining of child occupants younger than 16, years were observed, the interior environment of the vehicles was examined, and a structured, interview of the driver was conducted according to a specific protocol.

RESULTS

In total, 1260 child occupants aged 0-15 years were included in the study. Misuse of restraints, was observed in 38% of cases, with this being severe or critical in 24%. The presence of restraint, misuse varied significantly with age (p<0.001), with the frequency being highest among child, occupants in the age group 4-7 years. The most common error in this group was improperly routed, seat belts. The highest frequency of severe and critical errors was observed among child occupants in, the age group 0-3 years. The most common errors were loose or improperly routed harness straps and, incorrect installations of the child restraint system. Moreover, 24% of the children were seated in, vehicles with heavy, unsecured objects in the passenger compartment and/or the trunk that were, likely to move into the compartment upon impact and cause injury. No totally unrestrained children, were observed.

CONCLUSIONS

This study provides a detailed description of the characteristics of restraint misuse and, the occupant's exposure to unsecured objects. Future education and awareness campaigns should, focus on children aged <8 years. The main challenges are to ensure correct routing and tightness of, harness straps and seat belts, correct installation of child restraints, and avoidance of premature, graduation from child restraints to seat belts only. Information campaigns should also advocate the use, of chest clips and address the potential risks of hard, heavy objects in the passenger compartment and, the importance of the placement and strapping of heavy objects in the trunk.

The relationship between vehicle roof crush and head, neck and spine injury in rollover crashes

BACKGROUND

It is well established that rollover crashes are associated with a higher risk of serious injury and death than other types of crashes. Some of the most serious injuries that can result from a rollover crash are those to the head, neck and spine. The mechanism of injury to these body parts in a rollover is a matter of dispute in the literature. Some authors have concluded that the magnitude of vehicle roof deformation or vertical roof crush resulting from a rollover crash is not causally associated with head and neck injury severity, while others offer support for a causal association between roof crush and the degree of injury. A better understanding of the cause of serious injuries resulting from rollover crashes is important for improving injury prevention.

METHODS

This study utilized data from the National Automotive Sampling System--Crashworthiness Data System (NASS-CDS) for the years 1997 through 2007. Both cross-sectional and matched case-control designs along with a new composite injury metric termed the Head, Neck and Spine New Injury Severity Score (HNS-NISS) were used to analyze these data.

RESULTS

The cross-sectional analysis demonstrated a 64% (95% CI: 26-114%) increase in the odds of a life-threatening injury as estimated by the HNS-NISS with every 10 cm of increased roof crush. The results of the matched case-control analysis demonstrated a 44% (95% CI: 8-91%) increase in the odds of sustaining any injury to the head, neck or spine with every 10 cm increase in roof crush.

CONCLUSION

These results lend statistical support to a causal association between roof crush and head, neck and spine injury severity. Though they do not constitute definitive proof, they do contradict previously published theories suggesting that roof deformation is unrelated to such injuries.

Injury incidence rates of cyclists compared to pedestrians, car occupants and powered two-wheeler riders, using a medical registry and mobility data, Rhône County, France

PURPOSE

In France, the bicycle's modal share is stabilizing after a decline; in some of France's major cities, it has even increased since the 1990s. It is hence relevant to improve the knowledge of the injury risk associated with cycling, compared with other means of transport such as car, walking and powered two-wheeler (PTW) riding.

METHODS

The injury incidence rates were estimated by the ratio between accident data and mobility (exposure) data. Two accident data sources were used: police data and hospital-based data (outpatients and inpatients) from the Rhône road trauma Registry. This provides four injury categories: all-injury, hospitalization, serious-injury and fatal-injury. Exposure data were estimated from a regional household travel survey (RTS), using three measures of mobility: number of trips, distance traveled and time spent traveling. The survey was carried out from November 2005 to April 2006, on weekdays, outside school and public holidays; this seasonality was corrected using the 2007-2008 national household travel survey (NTS) that covered an entire year. Only information involving accidents and trips in, and residents of, the Rhône County (1.6 million inhabitants, including the city Lyon) were included in our study. Trends of injury rates were also evaluated in Greater Lyon, using previous travel surveys.

RESULTS

The PTW riders had the highest all-injury, hospitalization, serious-injury and fatal-injury rates, followed by cyclists, and lastly by pedestrians and car occupants. The rates between men and women seemed similar among pedestrians and among car occupants. For car occupants, pedestrians and cyclists, the age group 18-25 years had higher all-injury rate compared with the age group 25-65 years. On the contrary, the age group≥65 years seemed to have higher hospitalization and serious-injury rates, compared with the age group 25-65 years. For cyclists, the injury rates seemed higher in non-dense areas than in dense areas. Between 1996-1997 and 2005-2006 and with regards to time spent traveling, the all-injury, serious-injury and fatal-injury rates seemed to have decreased for car occupants and cyclists.

CONCLUSION

The higher risk for PTW riders is confirmed and quantified; it is very high. Decrease in injury rates seems more marked for cyclists; this may indicate the "safety in numbers" effect. Countermeasures for improving road safety could be implemented, especially for vulnerable road user types. However, they will not be sufficient to fill in the gap between the much higher risk for PTW riders and that of car occupants. Exposure-based injury rates can be a tool for monitoring and evaluating the effectiveness of policies and programs, and for comparisons between countries.

Transfusion of red blood cells in patients with a prehospital Glasgow Coma Scale score of 8 or less and no evidence of shock is associated with worse outcomes

BACKGROUND

Red blood cell transfusion practices vary, and the optimal hemoglobin for patients with traumatic brain injury has not been established.

METHODS

A retrospective review of data collected prospectively as part of a randomized, controlled trial involving emergency medical service agencies within the Resuscitation Outcomes Consortium was conducted. In patients with a Glasgow Coma Scale (GCS) score of 8 or less without evidence of shock (defined by a systolic blood pressure [SBP] < 70 or SBP of 70 to 90 with a heart rate ≥108), the association of red blood cell transfusion with 28-day survival, adult respiratory distress syndrome-free survival, Multiple Organ Dysfunction Score (MODs), and 6-month Extended Glasgow Outcome Scale (GOSE) score was modeled using multivariable logistic regression with robust SEs adjusting for age, sex, injury severity (Injury Severity Score [ISS]), initial GCS score, initial SBP, highest field heart rate, penetrating injury, fluid use, study site, and hemoglobin (Hgb) level.

RESULTS

A total of 1,158 patients had a mean age of 40, 76% were male, and 98% experienced blunt trauma. The initial mean GCS score was 5, and the initial mean SBP was 134. The mean head Abbreviated Injury Scale (AIS) score was 3.5. A categorical interaction of red blood cell transfusion stratified by initial Hgb showed that when the first Hgb was greater than 10 g/dL, volume of packed red blood cell was associated with a decreased 28-day survival (odds ratio, 0.83; 95% confidence interval [CI], 0.74-0.93; p < 0.01) and decreased adult respiratory distress syndrome-free survival (odds ratio, 0.82; 95% CI, 0.74-0.92; p < 0.01). When the initial Hgb was greater than 10, each unit of blood transfused increased the MODs by 0.45 (coefficient 95% CI, 0.19-0.70; p < 0.01).

CONCLUSION

In patients with a suspected traumatic brain injury and no evidence of shock, transfusion of red blood cells was associated with worse outcomes when the initial Hgb was greater than 10.

LEVEL OF EVIDENCE

Therapeutic study, level III.

Development of a robust mapping between AIS 2+ and ICD-9 injury codes

Motor vehicle crashes result in millions of injuries and thousands of deaths each year in the United States. While most crash research datasets use Abbreviated Injury Scale (AIS) codes to identify injuries, most hospital datasets use the International Classification of Diseases, version 9 (ICD-9) codes. The objective of this research was to establish a one-to-one mapping between AIS and ICD-9 codes for use with motor vehicle crash injury research. This paper presents results from investigating different mapping approaches using the most common AIS 2+ injuries from the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS). The mapping approaches were generated from the National Trauma Data Bank (NTDB) (428,637 code pairs), ICDMAP (2500 code pairs), and the Crash Injury Research and Engineering Network (CIREN) (4125 code pairs). Each approach may pair given AIS code with more than one ICD-9 code (mean number of pairs per AIS code: NTDB=211, ICDMAP=7, CIREN=5), and some of the potential pairs are unrelated. The mappings were evaluated using two comparative metrics coupled with qualitative inspection by an expert physician. Based on the number of false mappings and correct pairs, the best mapping was derived from CIREN. AIS and ICD-9 codes in CIREN are both manually coded, leading to more proper mappings between the two. Using the mapping presented herein, data from crash and hospital datasets can be used together to better understand and prevent motor vehicle crash injuries in the future.

Comparative outcome of bomb explosion injuries versus high-powered gunshot injuries of the upper extremity in a civilian setting

BACKGROUND

Explosion injuries to the upper extremity have specific clinical characteristics that differ from injuries due to other mechanisms.

OBJECTIVES

To evaluate the upper extremity injury pattern of attacks on civilian targets, comparing bomb explosion injuries to gunshot injuries and their functional recovery using standard outcome measures.

METHODS

Of 157 patients admitted to the hospital between 2000 and 2004, 72 (46%) sustained explosion injuries and 85 (54%) gunshot injuries. The trauma registry files were reviewed and the patients completed the DASH Questionnaire (Disabilities of Arm, Shoulder and Hand) and SF-12 (Short Form-12) after a minimum period of 1 year.

RESULTS

Of the 157 patients, 72 (46%) had blast injuries and 85 (54%) had shooting injuries. The blast casualties had higher Injury Severity Scores (47% vs. 22% with a score of > 16, P = 0.02) and higher percent of patients treated in intensive care units (47% vs. 28%, P = 0.02). Although the Abbreviated Injury Scale score of the upper extremity injury was similar in the two groups, the blast casualties were found to have more bilateral and complex soft tissue injuries and were treated surgically more often. No difference was found in the SF-12 or DASH scores between the groups at follow up.

CONCLUSIONS

The casualties with upper extremity blast injuries were more severely injured and sustained more bilateral and complex soft tissue injuries to the upper extremity. However, the rating of the local injury to the isolated limb is similar, as was the subjective functional recovery.

Should uncooperative trauma patients with suspected head injury be intubated?

In trauma patients with a suspicion for traumatic brain injury (TBI), a head computed tomography (CT) scan is imperative. However, uncooperative patients often cannot undergo imaging without sedation and may need to be intubated. Our hypothesis was that among mildly injured trauma patients, in whom there is a suspicion of a head injury, uncooperative patients have higher rates of TBI and intubation should be considered to obtain a CT scan. We found that uncooperative patients intubated for diagnostic purposes were more likely to have moderate to severe TBI than nonintubated patients (21.4 vs. 8.4%, P < 0.0001) and uncooperative behavior leading to intubation was an independent predictor of TBI (odds ratio, 2.5; 95% confidence interval, 1.5 to 4.5). Of patients with brain injury, intubated patients more often had a head abbreviated injury scale score of 4 (20.8 vs. 7.9%, P = 0.04). Uncooperative intubated patients had longer hospital stays (3.6 vs. 2.6 days, P = 0.003) and higher mortality (0.9 vs. 0.2%, P = 0.02) than nonintubated patients. Uncooperative behavior may be an early warning sign of TBI and the trauma surgeon should consider intubating uncooperative trauma patients if there is suspicion for brain injury based on the mechanism of their trauma.

Effects of BMI on the risk and frequency of AIS 3+ injuries in motor-vehicle crashes

OBJECTIVE

Determine the effects of BMI on the risk of serious-to-fatal injury (Abbreviated Injury Scale ≥ 3 or AIS 3+) to different body regions for adults in frontal, nearside, farside, and rollover crashes.

DESIGN AND METHODS

Multivariate logistic regression analysis was applied to a probability sample of adult occupants involved in crashes generated by combining the National Automotive Sampling System (NASS-CDS) with a pseudoweighted version of the Crash Injury Research and Engineering Network database. Logistic regression models were applied to weighted data to estimate the change in the number of occupants with AIS 3+ injuries if no occupants were obese.

RESULTS

Increasing BMI increased risk of lower-extremity injury in frontal crashes, decreased risk of lower-extremity injury in nearside impacts, increased risk of upper-extremity injury in frontal and nearside crashes, and increased risk of spine injury in frontal crashes. Several of these findings were affected by interactions with gender and vehicle type. If no occupants in frontal crashes were obese, 7% fewer occupants would sustain AIS 3+ upper-extremity injuries, 8% fewer occupants would sustain AIS 3+ lower-extremity injuries, and 28% fewer occupants would sustain AIS 3+ spine injuries.

CONCLUSIONS

Results of this study have implications on the design and evaluation of vehicle safety systems.

Impact speed and a pedestrian's risk of severe injury or death

This study estimates the risk of severe injury or death for pedestrians struck by vehicles using data from a study of crashes that occurred in the United States in years 1994-1998 and involved a pedestrian struck by a forward-moving car, light truck, van, or sport utility vehicle. The data were weighted to correct for oversampling of pedestrians who were severely injured or killed. Logistic regression was used to adjust for potential confounding related to pedestrian and vehicle characteristics. Risks were standardized to represent the average risk for a pedestrian struck by a car or light truck in the United States in years 2007-2009. Results show that the average risk of a struck pedestrian sustaining an injury of Abbreviated Injury Scale 4 or greater severity reaches 10% at an impact speed of 17.1miles per hour (mph), 25% at 24.9mph, 50% at 33.0mph, 75% at 40.8mph, and 90% at 48.1mph. The average risk of death reaches 10% at an impact speed of 24.1mph, 25% at 32.5mph, 50% at 40.6mph, 75% at 48.0mph, and 90% at 54.6mph. Risks varied by age. For example, the average risk of death for a 70-year-old pedestrian struck at any given speed was similar to the average risk of death for a 30-year-old pedestrian struck at a speed 11.8mph faster.

The practicality of including the systemic inflammatory response syndrome in the definition of polytrauma: experience of a level one trauma centre

BACKGROUND

The systemic inflammatory response syndrome (SIRS) has been advocated as a significant predictor of outcome in trauma. Recent trauma literature has proposed SIRS as a surrogate for physiological derangements characteristic of polytrauma with some authors recommending its inclusion into the definition of polytrauma. The practicality of daily SIRS collection outside of specifically designed prospective trials is unknown. The purpose of this study was to assess the availability of SIRS variables and its appropriateness for inclusion into a definition of polytrauma. We hypothesised SIRS variables would be readily available and easy to collect, thus represent an appropriate inclusion into the definition of polytrauma.

METHOD

A prospective observational study of all trauma team activation patients over 7-months (August 2009 to February 2010) at a University affiliated level-1 urban trauma centre. SIRS data (temperature>38°C or <36°C; Pulse >90 bpm; RR>20/min or a PaCO(2)<32 mmHg; WCC>12.0×10(9)L(-1), or <4.0×10(9)L(-1), or the presence of >10 immature bands) collected from presentation, at 24 h intervals until 72 h post injury. Inclusion criteria were all patients generating a trauma team activation response age >16.

RESULTS

336 patients met inclusion criteria. In 46% (155/336) serial SIRS scores could not be calculated due to missing data. Lowest rates of missing data observed on admission [3% (11/336)]. Stratified by ISS>15 (132/336), in 7% (9/132) serial SIRS scores could not be calculated due to missing data. In 123 patients ISS>15 with complete data, 81% (100/123) developed SIRS. For Abbreviated Injury Scale (AIS)>2 in at least 2 body regions (64/336) in 5% (3/64) serial SIRS scores could not be calculated, with 92% (56/61) of patients with complete data developing SIRS. For Direct ICU admissions [25% (85/336)] 5% (4/85) of patients could not have serial SIRS calculated [mean ISS 15(±11)] and 90% (73/81) developed SIRS at least once over 72 h.

CONCLUSION

Based on the experience of our level-1 trauma centre, the practicability of including SIRS into the definition of polytrauma as a surrogate for physiological derangement appears questionable even in prospective fashion.

An investigation on the head injuries of adult pedestrians by passenger cars in China

OBJECTIVE

To investigate the relative likelihood of pedestrian head injuries based on person, vehicular, and environmental factors in China.

METHODS

A team was established to collect passenger car-pedestrian accident cases occurring between 2006 and 2011 in Beijing, Shanxi Province, and Chongqing, China. Some key variables for person-, vehicle-, and environment-related factors on head injuries were analyzed using multivariate logistic regression analysis to determine relative risk/likelihood. Pedestrians were classified according to injury outcome and age. Pedestrian head injuries were scored using the Abbreviated Injury Scale (AIS).

RESULTS

A total of 285 vehicle-pedestrian crashes were collected and analyzed: 30 in Beijing, 20 in Shanxi Province, and 235 in Chongqing. The distribution in age and road type by study location differed. The injury outcome, head injury severity, and head contact site were different among 4 age groups. The variables including head contact site and impact speed were the common determinants for head injury severity. A higher pedestrian fatality risk was associated with age over 46, impact speeds over 40 km/h, and higher likelihoods of the victim's head striking the windscreen frame/A pillar and of the victim sustaining a head injury. Similarly, a higher risk of head injury was associated with being female, age over 60, impact speeds over 40 km/h, and a likelihood of the victim's head striking the vehicle rather than the ground. Impact speeds of over 40 km/h and head contact site on windscreen frame/A pillar retained a strong association with severe head injury (AIS 5-6) rate.

CONCLUSIONS

Pedestrian age, vehicle impact speed, and head contact site were common pertinent factors for the risk of pedestrian head injury and the risk of death. Further studies would be valuable to fully characterize vehicle-pedestrian crashes in China and to develop targeted injury prevention strategies based on surveillance results.

A structured autopsy-based audit of 370 firearm fatalities: Contribution to inform policy decisions and the probability of the injured arriving alive at a hospital and receiving definitive care

The objectives of this autopsy-based audit of firearm-related fatalities were to acquire data to inform policy decisions and to assess the probability of the injured arriving alive at a hospital and receiving definitive care.

EVALUATED VARIABLES

Demographics; co-morbidities; location and intention of the injury; toxicology; types of firearms; Abbreviated Injury Scale; Injury Severity Score (ISS); transfer means and time; and location of death.

RESULTS

Of a total of 370 fatalities, 85.7% were male. The median age was 38 (9-95) years. Suicides (47%) and assaults (45.1%) were the most common underlying intentions. The most seriously injured regions were the head (44.5%), thorax (25.7%), abdomen (10.7%), and spine (5.7%). Of the 370 total subjects, 4.9% had an ISS<16 and 59.5% had an ISS≤74; both groups were classified as potentially preventable deaths. The majority (84%) died at the scene, and only 9.8% left the emergency department alive for further treatment. Multivariate analyses documented that postmortem ISS is an independent factor that predicts the probability of the injured reaching a hospital alive and receiving definitive care. Individuals injured in greater Athens and those most seriously injured in the face, abdomen or spine had significantly greater chances of reaching a hospital alive and receiving definitive care, whereas those injured by a shotgun and the positive toxicology group were significantly less likely to. In conclusion, this study provides data to inform policy decisions, calls for a surveillance network and establishes a baseline for estimating the probability regarding the location of firearm-related deaths.