Accuracy of Instrumented Mouthguards During Direct Jaw Impacts Seen in Boxing.

PURPOSE: Measuring head kinematics data is important to understand and develop methods and standards to mitigate head injuries in contact sports. Instrumented mouthguards (iMGs) have been developed to address coupling issues with previous sensors. Although validated with anthropomorphic test devices (ATDs), there is limited post-mortem human subjects (PMHS) data which provides more accurate soft tissue responses. This study evaluated two iMGs (Prevent Biometrics (PRE) and Diversified Technical Systems (DTS) in response to direct jaw impacts. METHODS: Three unembalmed male cadaver heads were properly fitted with two different boil-and-bite iMGs and impacted with hook (4 m/s) and uppercut (3 m/s) punches. A reference sensor (REF) was rigidly attached to the base of the skull, impact kinematics were transformed to the head center of gravity and linear and angular kinematic data were compared to the iMGs including Peak Linear Acceleration, Peak Angular Acceleration, Peak Angular Velocity, Head Injury Criterion (HIC), HIC duration, and Brain Injury Criterion. RESULTS: Compared to the REF sensor, the PRE iMG underpredicted most of the kinematic data with slopes of the validation regression line between 0.72 and 1.04 and the DTS overpredicted all the kinematic data with slopes of the regression line between 1.4 and 8.7. CONCLUSION: While the PRE iMG was closer to the REF sensor compared to the DTS iMG, the results did not support the previous findings reported with use of ATDs. Hence, our study highlights the benefits of using PMHS for validating the accuracy of iMGs since they closely mimic the human body compared to any ATD's mandible.

Biofidelity and Limitations of Instrumented Mouthguard Systems for Assessment of Rigid Body Head Kinematics.

Instrumented mouthguard systems (iMGs) are commonly used to study rigid body head kinematics across a variety of athletic environments. Previous work has found good fidelity for iMGs rigidly fixed to anthropomorphic test device (ATD) headforms when compared to reference systems, but few validation studies have focused on iMG performance in human cadaver heads. Here, we examine the performance of two boil-and-bite style iMGs in helmeted cadaver heads. Three unembalmed human cadaver heads were fitted with two instrumented boil-and-bite mouthguards [Prevent Biometrics and Diversified Technical Systems (DTS)] per manufacturer instructions. Reference sensors were rigidly fixed to each specimen. Specimens were fitted with a Riddell SpeedFlex American football helmet and impacted with a rigid impactor at three velocities and locations. All impact kinematics were compared at the head center of gravity. The Prevent iMG performed comparably to the reference system up to ~ 60 g in linear acceleration, but overall had poor correlation (CCC = 0.39). Prevent iMG angular velocity and BrIC generally well correlated with the reference, while underestimating HIC and overestimating HIC duration. The DTS iMG consistently overestimated the reference across all measures, with linear acceleration error ranging from 10 to 66%, and angular acceleration errors greater than 300%. Neither iMG demonstrated consistent agreement with the reference system. While iMG validation efforts have utilized ATD testing, this study highlights the need for cadaver testing and validation of devices intended for use in-vivo, particularly when considering realistic (non-idealized) sensor-skull coupling, when accounting for interactions with the mandible and when subject-specific anatomy may affect device performance.

A comparison of gelatine surrogates for wound track assessment.

The use of ordnance gelatine has been widespread in the field of ballistics as a simulant for soft tissue when assessing ballistic threats. However, the traditional method of preparing ordnance gelatine is time-consuming and requires precision to ensure that the final mold meets the required specifications. Furthermore, temperature control is necessary post-production, and there are limitations on its usage duration. To address these issues, manufacturers have developed pre-mixed, gelatine-like products that are stable at room temperature and require less preparation time. Nonetheless, it is uncertain whether these new products can perform in the same manner as the gold standard of ordnance gelatine. This study used five types of blocks, including ordnance gelatine (10% and 20%), Clear Ballistics (10% and 20%) and Perma-Gel (10%) and subjected them to 9 mm, 0.380 Auto fired from a universal receiver and a 5.56 × 45 mm ammunition fired by a certified firearms instructor. Delta-V and total energy dissipation were measured after each test using data collected from ballistic chronographs placed in front of and behind each block. High-speed video was recorded, and a cut-down analysis conducted. The findings revealed variations in energy dissipation and fissure formation within the block, with greater energy based on fissure formation observed in the ordnance gelatine. Additionally, the high-speed video showed the occurrence of secondary combustions occurring in the premixed gelatines.

Development of the NOCSAE Standard to Reduce the Risk of Commotio Cordis.

BACKGROUND: Commotio cordis, sudden cardiac death (SCD) caused by relatively innocent impact to the chest, is one of the leading causes of SCD in sports. Commercial chest protectors have not been demonstrated to mitigate the risk of these SCDs. METHODS: To develop a standard to assess chest protectors, 4 phases occurred. A physiological commotio cordis model was utilized to assess variables that predicted for SCD. Next, a surrogate model was developed based on data from the physiological model, and the attenuation in risk was assessed. In the third phase, this model was calibrated and validated. Finally, National Operating Committee on Standards for Athletic Equipment adopted the standard and had an open review process with revision of the standard over 3 years. RESULTS: Of all variables, impact force was the most robust at predicting SCD. Chest wall protectors which could reduce the force of impact to under thresholds were predicted to reduce the risk of SCD. The correlation between the experimental model and the mechanical surrogate ranged from 0.783 with a lacrosse ball at 30 mph to 0.898 with a baseball at 50 mph. The standard was licensed to National Operating Committee on Standards for Athletic Equipment which initially adopted the standard in January 2018, and finalized in July 2021. CONCLUSIONS: An effective mechanical surrogate based on physiological data from a well-established model of commotio cordis predicts the reduction in SCD with chest protectors. A greater reduction in force provides a great degree of protection from commotio cordis. This new National Operating Committee on Standards for Athletic Equipment standard for chest protectors should result in a significant reduction in the risk of commotio cordis on the playing field.

Longitudinal, prospective study of head impacts in male high school football players.

INTRODUCTION: Repetitive, subconcussive events may adversely affect the brain and cognition during sensitive periods of development. Prevention of neurocognitive consequences of concussion in high school football is therefore an important public health priority. We aimed to identify the player positions and demographic, behavioral, cognitive, and impact characteristics that predict the frequency and acceleration of head impacts in high school football players. METHODS: In this prospective study, three cohorts of adolescent male athletes (N = 53, 28.3% Hispanic) were recruited over three successive seasons in a high school American football program. Demographic and cognitive functioning were assessed at baseline prior to participating in football. Helmet sensors recorded impact frequency and acceleration. Each head impact was captured on film from five different angles. Research staff verified and characterized on-field impacts. Player-level Poisson regressions and year-level and impact-level linear mixed-effect models were used to determine demographic, behavioral, cognitive, and impact characteristics as predictors of impact frequency and acceleration. RESULTS: 4,678 valid impacts were recorded. Impact frequency positively associated with baseline symptoms of hyperactivity-impulsivity [ß(SE) = 1.05 impacts per year per unit of symptom severity (1.00), p = 0.01] and inattentiveness [ß(SE) = 1.003 impacts per year per T-score unit (1.001), p = 0.01]. Compared to quarterbacks, the highest acceleration impacts were sustained by kickers/punters [ß(SE) = 21.5 g's higher (7.1), p = 0.002], kick/punt returners [ß(SE) = 9.3 g's higher (4.4), p = 0.03], and defensive backs [ß(SE) = 4.9 g's higher (2.5), p = 0.05]. Impacts were more frequent in the second [ß(SE) = 33.4 impacts (14.2), p = 0.02)] and third [ß(SE) = 50.9 impacts (20.1), p = 0.01] year of play. Acceleration was highest in top-of-the-head impacts [ß(SE) = 4.4 g's higher (0.8), p<0.001]. CONCLUSION: Including screening questions for Attention-Deficit/Hyperactivity Disorder in pre-participation evaluations can help identify a subset of prospective football players who may be at risk for increased head impacts. Position-specific strategies to modify kickoffs and correct tackling and blocking may also reduce impact burden.

Assessment of a Perfusion and Ventilation Method for Detecting Lung and Liver Injury in a Cadaveric Model.

Surgical simulation models have been developed using post-mortem human subjects (PMHS). These models involve the pressurization and ventilation of the PMHS to create a more realistic environment for training and the practice of surgical procedures. The overall objective of this study was to determine the feasibility of a previously developed surgical simulation model to detect soft tissue injuries during a ballistic impact to the torso. One of the main limitations of using PMHS for the assessment of soft tissue injuries in the field of injury biomechanics is the lack of physiological blood flow. To overcome this limitation, the assessment of the surgical simulation model for use in injury biomechanics applications was conducted based on data collected from behind armor blunt trauma (BABT) case studies. Documented injuries in real-world cases included anterior lung contusion, posterior lung contusion, and liver contusion. These real-world injuries were compared to those seen post-impact in the PMHS using pathological and histological techniques. Discussion of limitations and future work is presented.

Dynamic Response of the Thoracolumbar and Sacral Spine to Simulated Underbody Blast Loading in Whole Body Post Mortem Human Subject Tests.

Fourteen simulated underbody blast impact sled tests were performed using a horizontal deceleration sled with the aim of evaluating the dynamic response of the spine in under various conditions. Conditions were characterized by input (peak velocity and time-to-peak velocity for the seat and floor), seat type (rigid or padded) and the presence of personnel protective equipment (PPE). A 50% (T12) and 30% (T8) reduction in the thoracic spine response for the specimens outfitted with PPE was observed. Longer duration seat pulses (55 ms) resulted in a 68-78% reduction in the magnitude of spine responses and a reduction in the injuries at the pelvis, thoracic and lumbar regions when compared to shorter seat pulses (10 ms). The trend analysis for the peak Z (caudal to cranial) acceleration measured along the spine showed a quadratic fit (p < 0.05), rejecting the hypothesis that the magnitude of the acceleration would decrease linearly as the load traveled caudal to cranial through the spine during an Underbody Blast (UBB) event. A UBB event occurs when an explosion beneath a vehicle propels the vehicle and its occupants vertically. Further analysis revealed a relationship (p < 0.01) between peak sacrum acceleration and peak spine accelerations measured at all levels. This study provides an initial analysis of the relationship between input conditions and spine response in a simulated underbody blast environment.

Incidence of law enforcement officer fatalities related to motor vehicle accidents.

A recent FBI report indicates that motor vehicle accidents (MVA) account for 71% of accidental law enforcement officer (LEO) fatalities. To better understand the factors surrounding these fatalities, a review of cases reported to the Officer Down Memorial Page (ODMP) was conducted. A total of 738 MVA fatalities over ten years were included in this analysis. When comparing younger (<34 years) to older officers (≥ 35 years), there was a statistically significant difference with more younger officers reported to have been going at a high rate of speed at the time of the accident (p = 0.011) and were involved more often in single car accidents (p = 0.0207). The data also indicated a fatality rate of 5.4 fatalities per 100,000 officers annually; twice that of other professionals involving high speed operations. Even given the downward trend of MVA fatalities, policy changes and training to help reduce these number of fatalities is warranted.

Size as an Important Determinant of Chest Blow-induced Commotio Cordis.

PURPOSE: Commotio cordis is sudden cardiac death caused by a relatively innocent blow to the left chest wall. Adolescents account for the majority of the cases; whether this is due to the higher frequency of adolescents playing ball sports or whether there is some maturational reduction of risk is not known. METHODS: In a swine model of commotio cordis, the effect of body weight/size (directly related to age) to the susceptibility of chest impact-induced ventricular fibrillation (VF) is examined. METHODS: Ball impacts were delivered at escalating velocities from 48.3 to 96.9 km·h (30-60 mph) to 128 swine ranging in weight from 5 to 54 kg. RESULTS: VF occurred in 29% of impacts to the smallest animals compared with 34% in the 14- to 239-kg group, 27% in the 24- to 33.9-kg group, 30% in 34- to 43-kg group, and 15% in the 44- to 54-kg animals. The highest-weight group was associated with a significantly lower incidence of VF compared with other weights (P = 0.002). In a multivariate logistic regression analysis, controlling for repeated measures, four variables predicted VF: body weight (P = 0.0008), velocity (P < 0.0001), distance from the center of the heart, (P < 0.0001), and peak left ventricular pressure induced by the blow (P = 0.0007). CONCLUSIONS: In this experimental model, animals weighing <44 kg seem to have a similar susceptibility to commotio cordis, whereas animals weighing ≥44 kg have a lower susceptibility. An increase in size of the individual, rather than reduced play of ball sports, is the likely reason for the decreased commotio cordis incidence in older individuals.

A Molecular Method to Detect Wound Cells in Bloodstains Resultant of Sharp Force Injuries for Crime Scene Reconstruction.

Previous research by the authors on an animal model showed that bloodstains can contain additional information about their somatic origin in the form of wound cells. Bloodstains produced by a gunshot wound to the head were distinguished from bloodstains produced by a gunshot wound to the chest by testing the stains for a brain microRNA marker. In this study, the effectiveness of the technique was examined on blood drops shed externally from a stab wound to the liver of rat carcasses. Specifically, investigations were conducted on the liver microRNA marker, rno-mir-122-3p, with the QIAGEN miScript System, and PCR analysis. Between the two stabbing methods used, 67% of the scalpel blades and 57% of the blood drops tested positive for rno-mir-122-3p; however, other samples tested negative giving inconclusive results as to the wound-of-origin. The amount of the liver cells in the bloodstains appeared to be related to the extent of trauma.

Injuries sustained during contact with law enforcement: An analysis from US trauma centers.

BACKGROUND: Injuries sustained by civilians from interaction with police are a polarizing contemporary sociopolitical issue. Few comprehensive studies have been published using national hospital-based data. The aim of this study was to examine the epidemiology of these injuries to better understand this mechanism of injury. METHODS: Patients entered into the National Trauma Data Bank (NTDB) (January 2007 to December 2012) with E-codes E970.0 to E976.0 (International Classification of Diseases, Ninth Revision, Clinical Modification), identifying injuries associated with law enforcement in the course of legal action, were enrolled. Patients' demographics, injury characteristics, procedures, and outcomes were collected and analyzed. Patients injured by other civilians (E960.0-E968.0) were used for comparison. RESULTS: Of 4,146,428 patients in the NTDB, 7,203 (0.17%) were injured during interaction with police. The numbers of patients in consecutive study years were 858, 1,103, 1,148, 1,274, 1,316, and 1,504. The incidence of these injuries was stable over time (0.17-0.18%) (p = 0.129). Patients had a median age of 31 years (range, 0-108), and 94.3% were male. Median injury severity score was 9 (interquartile range [IQR], 4-17). The most common mechanism of injury was gunshot wound (44%).Patients were white, 43%; black, 30%; Hispanic, 17%; Asian, 1%; and Other, 9%. As a proportion of the total race-specific NTDB trauma population, there was an average of 1.13 white patients, 2.71 Hispanic patients, and 3.83 black patients per 1,000. Mechanism, injury severity score, and outcomes did not vary by race. Compared to patients injured by civilians, patients injured by police are more likely to be white (43% vs 25%, p < 0.001) and injured by gunshot wounds (44% vs 32%, p < 0.001). CONCLUSIONS: Based on data from trauma centers across the United States, the rate of injuries sustained during interactions with police has been stable over time. Gunshot wounds are the most common mechanism of injury. Proportionally, black patients are the most frequently injured race. When compared to patients injured by civilians, however, patients injured by police are more likely to be white. This study provides a step toward a better understanding of police-associated injuries. LEVEL OF EVIDENCE: Prognostic/epidemiologic study, level III.

Use of a Novel, Portable, LED-Based Capillary Refill Time Simulator within a Disaster Triage Context.

Introduction A simple, portable capillary refill time (CRT) simulator is not commercially available. This device would be useful in mass-casualty simulations with multiple volunteers or mannequins depicting a variety of clinical findings and CRTs. The objective of this study was to develop and evaluate a prototype CRT simulator in a disaster simulation context. METHODS: A CRT prototype simulator was developed by embedding a pressure-sensitive piezo crystal, and a single red light-emitting diode (LED) light was embedded, within a flesh-toned resin. The LED light was programmed to turn white proportionate to the pressure applied, and gradually to return to red on release. The time to color return was adjustable with an external dial. The prototype was tested for feasibility among two cohorts: emergency medicine physicians in a tabletop exercise and second year medical students within an actual disaster triage drill. The realism of the simulator was compared to video-based CRT, and participants used a Visual Analog Scale (VAS) ranging from "completely artificial" to "as if on a real patient." The VAS evaluated both the visual realism and the functional (eg, tactile) realism. Accuracy of CRT was evaluated only by the physician cohort. Data were analyzed using parametric and non-parametric statistics, and mean Cohen's Kappas were used to describe inter-rater reliability. RESULTS: The CRT simulator was generally well received by the participants. The simulator was perceived to have slightly higher functional realism (P=.06, P=.01) but lower visual realism (P=.002, P=.11) than the video-based CRT. Emergency medicine physicians had higher accuracy on portrayed CRT on the simulator than the videos (92.6% versus 71.1%; P<.001). Inter-rater reliability was higher for the simulator (0.78 versus 0.27; P<.001). CONCLUSIONS: A simple, LED-based CRT simulator was well received in both settings. Prior to widespread use for disaster triage training, validation on participants' ability to accurately triage disaster victims using CRT simulators and video-based CRT simulations should be performed. Chang TP , Santillanes G , Claudius I , Pham PK , Koved J , Cheyne J , Gausche-Hill M , Kaji AH , Srinivasan S , Donofrio JJ , Bir C . Use of a novel, portable, LED-based capillary refill time simulator within a disaster triage context. Prehosp Disaster Med. 2017;32(4):451-456.

The Interaction of Intramuscular Ketorolac (Toradol) and Concussion in a Rat Model.

The purpose of this study was to examine the interaction of a single dose of Toradol and head impact in an in vivo rat model for sport-related concussion using a validated rat concussion model. Thirty-five Sprague-Dawley rats were placed into one of four groups: (1) Control, (2) Impact Only, (3) Toradol Only, (4) Impact and Toradol. Animals in the impact groups were subjected to a single head impact. Animals in the Toradol group received a single intramuscular injection of Toradol prior to impact. We examined magnetic resonance imaging, serum S100-B and cognitive function using a Morris Water Maze. In the control group, latency decreased significantly from day 0 (74.9 s) to 24 h (57.4 s) after anesthesia. There was no statistically significant difference between time zero and 24 h after impact in the Impact only or Impact and Toradol group. Our findings indicate that there were no differences between cognitive ability, MRI findings or S100B in rats that were administered a single dose of Toradol and subjected to a single impact and rats that were subjected to a single impact only. In both impact groups there were transient changes in cognitive ability as measured by the Morris Water Maze.

Fatal Injuries of Law Enforcement/Correctional Officers Attacked with Sharp-Edged Weapons.

According to the National Law Enforcement Memorial Fund, there were 117 law enforcement fatalities in the United States in 2015. Assaults with sharp-edged weapons have resulted in a total of over 400 fatalities in the United States. The goal of the current research was to examine sharp-edged weapon assaults against law enforcement and correctional agents that resulted in a fatal outcome. A total of twelve autopsy reports were reviewed from across the United States. Four cases involved law enforcement officers, seven involved correctional officers, and one was an off-duty border officer. The male-to-female ratio was 11:1. A total of 70.2% of the wounds analyzed were stab wounds (n = 85), and 29.8% of the wounds were slash wounds (n = 36). Based on this review, the neck, shoulder, and chest regions were the most vulnerable to single fatal stab/slash wounds. Multiple stab/slash wounds often resulted in exsanguination. The use of body armor was only noted in one case.

Ultrasound characteristics of bruises and their correlation to cutaneous appearance.

OBJECTIVE: The primary objective of this study was to compare the cutaneous size of a bruise on gross exam to the subcutaneous depth and height of the hematoma ascertained by ultrasound. The hypothesis was that there would be little correlation between the area of the bruise on cutaneous exam and the height when measured with ultrasound. METHODS: Adult and pediatric patients with bruising were prospectively identified in the emergency department. Photographs and ultrasound images were collected of the bruises and epidemiologic information collected from the patients. The cutaneous area of the bruise was compared with the sonographic characteristics. RESULTS: The subcutaneous depth and height of the hematomas defined by ultrasound did not correlate with the cutaneous area. CONCLUSIONS: The cutaneous appearance of a bruise gives little indication of the depth and size of the subcutaneous bruise. Ultrasound can add information regarding these parameters.

Evaluation of bone surrogates for indirect and direct ballistic fractures.

The mechanism of injury for fractures to long bones has been studied for both direct ballistic loading as well as indirect. However, the majority of these studies have been conducted on both post-mortem human subjects (PMHS) and animal surrogates which have constraints in terms of storage, preparation and testing. The identification of a validated bone surrogate for use in forensic, medical and engineering testing would provide the ability to investigate ballistic loading without these constraints. Two specific bone surrogates, Sawbones and Synbone, were evaluated in comparison to PMHS for both direct and indirect ballistic loading. For the direct loading, the mean velocity to produce fracture was 121 ± 19 m/s for the PMHS, which was statistically different from the Sawbones (140 ± 7 m/s) and Synbone (146 ± 3 m/s). The average distance to fracture in the indirect loading was .70 cm for the PMHS. The Synbone had a statistically similar average distance to fracture (.61 cm, p=0.54) however the Sawbones average distance to fracture was statistically different (.41 cm, p<0.05). Fractures patterns were found to be comparable to the PMHS for tests conducted with Synbones, however the input parameters were slightly varied to produce similar results. The fractures patterns with the Sawbones were not found to be as comparable to the PMHS. An ideal bone surrogate for ballistic testing was not identified and future work is warranted.

A biomechanical evaluation of skull-brain surrogates to blunt high-rate impacts to postmortem human subjects.

The field of forensic injury biomechanics is an emerging field. Biomechanically validated tools may assist interdisciplinary teams of investigators in assessing mechanisms of blunt head trauma resulting in skull fractures. The objective of this study is to assess the biofidelity of spherical, frangible skull-brain (SB) surrogates. Blunt impacts were conducted at 20 m/s, using an instrumented 103 g rigid impactor, to the temporo-parietal region of four defleshed cephalic postmortem human subjects (PMHS). Force-deformation response, fracture tolerance, and fracture patterns were recorded for comparison to spherical skull-brain surrogates. Three brain substitutes were assessed: 10% gelatin, lead shot with Styrofoam and water. Force-deformation response of the skull-brain surrogates was similar to defleshed PMHS up to the point of fracture; however, none of the surrogates fractured at tolerance levels comparable to the PMHS. Fracture patterns of the skull-brain surrogates were linear and radiating, while PMHS fractures were all depressed, comminuted.

Comparison of two fixation methods for arthrodesis of the calcaneocuboid joint: a biomechanical study.

BACKGROUND: The traditional fixation for a calcaneocuboid (CC) arthrodesis in triple arthrodesis is with a 6.5-mm cancellous screw. This procedure can be technically challenging. Fixation with a locking compression plate (LCP) may be easier to perform while achieving compression perpendicular to the fusion site. The purpose of this study was to compare the load to failure and the stiffness for each fixation method. METHODS: Five matched-pair cadaver feet had an arthrodesis of the CC joint. For each matched pair, one was fixed with a screw and the other with an LCP. Surface bead markers were applied. Each specimen was then secured to a material testing machine through the calcaneus. The plantar surface of the cuboid faced the hydraulic ram to simulate weightbearing. A force was applied while the specimen was recorded with a high-resolution camera. The endpoint was maximal force at 2-mm separation between the calcaneus and cuboid measured along a horizontal axis. RESULTS: The average force to failure and the average stiffness in the screw group were significantly less than the LCP group (P < .05). The screw construct failed in pullout from the cuboid; the LCP construct failed by plastic deformation of the plate. CONCLUSION: Calcaneocuboid joint fixation with the LCP withstood a higher load until failure and demonstrated greater stiffness than with a 6.5-mm cancellous lag screw. CLINICAL RELEVANCE: The use of LCP fixation can be considered as an alternative to oblique lag screw fixation for CC arthrodesis in a triple arthrodesis. It remains to be determined if LCP fixation leads to better clinical outcomes.

Review of Canine Deaths While in Service in US Civilian Law Enforcement (2002-2012).

BACKGROUND: Working dogs have been proven effective in multiple military and law enforcement applications. Similar to their human counterparts, understanding mortality while still in service can help improve treatment of injuries, and improve equipment and training, to potentially reduce deaths. This is a retrospective study to characterize mortality of working dogs used in civilian law enforcement. METHODS: Reported causes of death were gathered from two working dog and law enforcement officer memorial websites. RESULTS: Of the 867 civilian law enforcement dogs reported to these memorial websites from 2002 to 2012 with reported causes of death while in service, the deaths of 318 were categorized as traumatic. The leading reported causes of traumatic death or euthanasia include trauma as a result of a vehicle strike, 25.8% (n=82); heatstroke, 24.8% (n=79); and penetrating ballistic trauma, 23.0% (n=73). CONCLUSION: Although the information gathered was from online sources, this study casts some light on the risks that civilian law enforcement dogs undergo as part of the tasks to which they are assigned. These data underscore the need for a comprehensive database for this specialized population of working dogs to provide the robust, reliable data needed to develop prevention and treatment strategies for this valuable resource.

Intravenously administered nanoparticles increase survival following blast trauma.

Explosions account for 79% of combat-related injuries, leading to multiorgan hemorrhage and uncontrolled bleeding. Uncontrolled bleeding is the leading cause of death in battlefield traumas as well as in civilian life. We need to stop the bleeding quickly to save lives, but, shockingly, there are no treatments to stop internal bleeding. A therapy that halts bleeding in a site-specific manner and is safe, stable at room temperature, and easily administered is critical for the advancement of trauma care. To address this need, we have developed hemostatic nanoparticles that are administered intravenously. When tested in a model of blast trauma with multiorgan hemorrhaging, i.v. administration of the hemostatic nanoparticles led to a significant improvement in survival over the short term (1 h postblast). No complications from this treatment were apparent out to 3 wk. This work demonstrates that these particles have the potential to save lives and fundamentally change trauma care.