Effects of different helmet-mounted devices on pilot's neck injury under simulated ejection.

The helmet plays an important role in protection of pilot's head and enhances the pilot's capabilities and performance significantly with the use of mounted devices such as the Night Vision Goggle (NVG). However, the use of helmet-mounted devices might increase the risk of injury due to the increased helmet weight and change in the centre of gravity of head. In this study, four helmets with different combinations of mounted devices were modelled in a validated human head-neck multi-body model to analyse their effects on the pilot's neck injury during simulated ejection. The probability of neck injury was evaluated and predicted using the Nij neck injury criteria and human injury risk curves, considering the tolerance of injury for upper and lower cervical segment. It was demonstrated that the helmet-mounted devices would increase the compression force and bending moment on cervical spine, especially for the lower cervical segments with higher Nij. In the cases with Night Vision Goggle, Nij of the lower cervical segment reached 0.54, which exceeded the requirement in aviation filed. For the cases with Visor, excessive extension occurred, resulting in a high Nij. The simulation results of this study could provide a reference for helmet and mounted devices design and offer a proposal for the protection of pilots during ejection.

The implementation of a neck strengthening exercise program in elite rugby union: A team case study over one season.

OBJECTIVES: To investigate the effect of a neck strengthening program on maximal isometric neck strength and incidence of head and neck injuries including concussion, and to evaluate the acceptability and feasibility of the program within one professional men's rugby union team over one season. DESIGN: Pre- and post-intervention study. METHODS: A phased neck strengthening program was implemented in one rugby union team (n = 26 Forward Group; n = 13 Back Group) throughout the 2020 Super Rugby season, with maximal isometric neck strength measured at each training phase. Strength changes were analysed using one-way, repeated measures analysis of variance and paired samples t-test. Injury data from 2019 to 2020 were compared using incidence rate ratios (IRR). Player and staff surveys, reported as percentage of agreement, assessed program acceptability and feasibility. RESULTS: Forward Group's neck flexors (p < 0.001), left-lateral flexors (p = 0.04) and flexor/extensor ratio (p < 0.001) and Back Group's neck flexors (p = 0.01) significantly improved across the season, with uncertain evidence to support the reduction of head and neck injuries (IRR:0.86 (0.23-2.56) and concussion (IRR:0.63 (0.06-3.34) between seasons. Survey responses revealed high percentages of agreement for the program's acceptability and feasibility. CONCLUSIONS: Targeted sport-specific neck exercises have the potential to increase the maximal isometric neck strength of professional rugby players and may assist in reducing head and neck injuries including concussion.

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

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

Targeting rule implementation decreases neck injuries in high school football: a national injury surveillance study.

OBJECTIVES: Neck injuries in football are attributed to helmet-to-helmet contact with youth players being at greatest risk. In 2014, the National Federation of State High School Associations (NFHS) implemented rules defining illegal contact against a defenseless player above the shoulders to reduce head and neck injuries in football players. This study evaluates whether rule implementation decreased rates of high school football neck injuries presenting to the emergency department (ED) pre-rule implementation (2009-2013) to post-rule implementation (2015-2019). METHODS: Data were queried from the National Electronic Injury Surveillance System for high school football players 14 to 18 years old diagnosed with a neck injury from 1 January 2009 to 31 December 2019. Narratives in the data were reviewed for mechanism of injury, setting, loss of consciousness (LOC), and type of injury. RESULTS: Between 2009 and 2019, an estimated 47,577 high school football neck injuries were diagnosed in EDs across the United States. 52.0% of neck injuries were sustained during competition compared to 48.0% during practice. A statistically significant (P = 0.004) decrease in neck injuries was realized from pre-rule implementation to post-rule implementation with averages of 5,278 and 3,481 injuries per year, respectively. Helmet-to-helmet neck injuries significantly (P = 0.04) decreased from pre- to post-rule implementation with averages of 851 and 508 injuries per year, respectively. Neck injuries sustained via other mechanisms were not affected by the 2014 rule implementation. CONCLUSION: This study is the first to identify a decrease in overall and helmet-to-helmet related neck injuries diagnosed in the ED following the 2014 NFHS targeting rule implementation. These findings add to the growing literature regarding the importance and efficacy of rule implementation in reducing sports-related neck injuries.

Eight Weeks of Self-Resisted Neck Strength Training Improves Neck Strength in Age-Grade Rugby Union Players: A Pilot Randomized Controlled Trial.

BACKGROUND: Greater neck strength is associated with fewer head and neck injuries. Neck-strengthening programs are commonly burdensome, requiring specialist equipment or significant time commitment, which are barriers to implementation. HYPOTHESIS: Completing a neck-strengthening program will increase isometric neck strength in age-group rugby players. STUDY DESIGN: A pilot randomized controlled exercise intervention study. LEVEL OF EVIDENCE: Level 2. METHODS: Twenty-eight U18 (under 18) male regional age-group rugby union players were randomized (intervention n =15/control n = 13). An 8-week exercise program was supervised during preseason at the regional training center. Control players continued their "normal practice," which did not include neck-specific strengthening exercises. The 3-times weekly trainer-led intervention program involved a series of 15-second self-resisted contractions, where players pushed maximally against their own head, in forward, backward, left, and right directions. OUTCOME MEASURE: Peak isometric neck strength (force N) into neck flexion, extension, and left and right side flexion was measured using a handheld dynamometer. RESULTS: Postintervention between-group mean differences (MDs) in isometric neck strength change were adjusted for baseline strength and favored the intervention for total neck strength (effect size [ES] = 1.2, MD ± 95% CI = 155.9 ± 101.9 N, P = 0.004) and for neck strength into extension (ES = 1.0, MD ± 95% CI = 59.9 ± 45.4 N, P = 0.01), left side flexion (ES = 0.7, MD ± 95% CI = 27.5 ± 26.9 N, P = 0.05), and right side flexion (ES = 1.3, MD ± 95% CI = 50.5 ± 34.4 N, P = 0.006). CONCLUSION: This resource-efficient neck-strengthening program has few barriers to implementation and provides a clear benefit in U18 players' neck strength. While the present study focused on adolescent rugby players, the program may be appropriate across all sports where head and neck injuries are of concern and resources are limited. CLINICAL RELEVANCE: Greater neck strength is associated with fewer head and neck injuries, including concussion. Performing this neck exercise program independently, or as part of a whole-body program like Activate, an interactive guide for players and coaches, could contribute to lower sports-related head and neck injuries.

Injury Reduction Programs for Reducing the Incidence of Sport-Related Head and Neck Injuries Including Concussion: A Systematic Review.

BACKGROUND: Sport-related head and neck injuries, including concussion, are a growing global public health concern with a need to explore injury risk reduction strategies such as neck exercises. OBJECTIVES: To systematically review the literature to investigate: (1) the relationship between neck strength and sport-related head and neck injuries (including sport-related concussion (SRC); and (2) whether neck exercise programs can reduce the incidence of (a) sport-related head and neck injuries; and (b) SRC. METHODS: Five databases (Ovid MEDLINE, CINAHL, EMBASE, SPORTDiscus, and Web of Science) and research lists of included studies were searched using a combination of medical subject headings and keywords to locate original studies which reported the association between incidence of head and/or neck injury and neck strength data, or included a neck exercise intervention either in isolation or as part of a more comprehensive exercise program. RESULTS: From an initial search of 593 studies, six were included in this review. A narrative synthesis was performed due to the heterogeneity of the included studies. The results of two observational studies reported that higher neck strength, but not deep neck flexor endurance, is associated with a lower risk of sustaining a SRC. Four intervention studies demonstrated that injury reduction programs that included neck exercises can reduce the incidence of sport-related head and neck injuries including SRC. CONCLUSION: Consideration should be given towards incorporating neck exercises into injury reduction exercise programs to reduce the incidence of sport-related head and neck injuries, including SRC. SYSTEMATIC REVIEW REGISTRATION: PROSPERO (registration number: 194217).

Head and Neck Injuries and Electronic Scooter Use in the United States.

OBJECTIVE: To quantify electric scooter injuries encountered in United States emergency departments, focusing on the head and neck, to understand the safety impact of these scooters to improve safe usage. STUDY DESIGN: Retrospective cross-sectional study from January 2009 to December 2019 of patients presenting to United States emergency departments with electric scooter injuries collected from a national database. About 2,823 cases of injuries were related to electric scooter use from January 2009 to December 2019. Stratified weighted counts and incidence rates were estimated for injury characteristics. Piecewise linear regression quantified the yearly change in incidence of injuries before and after introduction of rideshare programs. RESULTS: The estimated national total of electric scooter cases from 2009 to 2019 was 103,943 (95% CI: 79,650-128,237). Incidence grew in 2019 to 8.63 cases per 100,000 person-years from 4.46 in 2018 to 2.42 in 2017. Head and neck injuries represented 28.5% of total injuries (weighted estimate = 29,610). The most common age group of head and neck injuries before 2018 was ≤17 years, but injuries in 18- to 44-year-olds grew significantly to become the most injured group in 2018 to 2019 (P < .001). From 2009 to 2017, incidence of head and neck injuries fell by 0.02 cases per 100,000 person-years, but cases grew by 1.22 cases per 100,000 person-years post-2017 (P < .001). CONCLUSION: Injuries following the launch of rideshare electric scooter programs increased significantly, especially in patients 18 to 44 years of age. Head and neck injuries represent many of these injuries. User safety education must be addressed to prevent injury as programs become more pervasive in the United States. LEVEL OF EVIDENCE: 2 Laryngoscope, 131:E2784-E2789, 2021.

Rule Modifications to Reduce Checking-Related Injuries in High School Boys' Lacrosse.

CONTEXT: The National Federation of State High School Associations previously implemented 2 lacrosse rule modifications: Rule 5.4 in the 2012-2013 academic year to heighten the penalty for a head or neck hit to the head, face, or neck (HFN) and Rule 5.3.5 in the 2013-2014 academic year to minimize body checking. OBJECTIVE: To determine if the rates of overall injury, HFN injuries, and concussions due to intentional contact (checking) differed for boys' high school lacrosse players after Rule 5.4 and 5.3.5 modifications were enacted. DESIGN: Descriptive epidemiology study. SETTING: Web-based online surveillance system. PATIENTS OR OTHER PARTICIPANTS: Boys' high school lacrosse players during the 2008-2009 to 2016-2017 seasons whose teams involved athletic trainers participating in the High School Reporting Information Online sports injury-surveillance system. INTERVENTION(S): Rule 5.4 in the 2012-2013 academic year increased the penalty for any intentional hits to the HFN, and Rule 5.3.5 in the 2013-2014 year eliminated body checking to a player in a defenseless position. MAIN OUTCOME MEASURE(S): Overall, HFN, and concussion injury rate ratios (IRRs) by checking mechanism; overall and checking-related injury ratios by competitions and practices. RESULTS: A decrease was shown in checking-related HFN injuries (IRR = 0.29, 95% CI = 0.13, 0.65) and checking-related concussions (IRR = 0.29, 95% CI = 0.12, 0.70) during practices in the seasons after both rule modifications were imposed, but no decreases occurred in any checking-related injuries during competitions. By injury mechanism, no decreases were evident after the Rule 5.4 modification. When both rule modifications (Rules 5.4 and 5.3.5) were enacted together, concussion rates due to delivering body checks (IRR = 0.51, 95% CI = 0.29, 0.91) and overall injury risk due to being body checked (IRR = 0.72, 95% CI = 0.53, 0.97) decreased. CONCLUSIONS: When both Rule 5.4 and 5.3.5 modifications were in effect, concussion and overall injury risks decreased for the body checker and the player being body checked, respectively.

Examining ski area padding for head and neck injury mitigation.

OBJECTIVES: The injury mitigation capabilities of foam, ski-area padding was examined for headfirst impacts. DESIGN AND METHODS: A custom-made pendulum impactor system was constructed using an instrumented, partial 50th-percentile-male Hybrid-III anthropomorphic testing device (ATD). For each test, the ATD was raised 1.0m, released, and swung into a 20-cm diameter wooden pole. Test trials were conducted with the wooden pole covered by ski area padding (five conditions of various foam types and thicknesses) or unpadded. Linear (linear acceleration and HIC15) and angular (angular velocity, angular acceleration, and BrIC) kinematics were examined and used to estimate the likelihood of severe brain injury. Cervical spine loads were compared to the injury assessment reference values for serious injury. Further tests were conducted to examine the changes produced by the addition of a snowsport helmet. RESULTS: 38 test trials were recorded with a mean (±sd) impact speed of 4.2 (±0.03) m/s. Head, resultant linear acceleration, HIC15, and associated injury likelihoods were tempered by ski area padding at the impact speed tested. Ski area padding did not reduce brain injury likelihood from rotational kinematics (p>0.05 for all comparisons) or reduce the cervical spine compression below injury assessment reference values. The addition of a helmet did not reduce significantly the likelihoods of brain or cervical spine injury. CONCLUSIONS: At the impact speed tested, ski area padding provided limited impact protection for the head (for linear kinematics) but did not protect against severe brain injuries due to rotational kinematics or serious cervical spine injuries.

Surface Contact Features, Impact Obliquity, and Preimpact Rotational Motion in Concussive Helmet-to-Ground Impacts: Assessment via a New Impact Test Device.

This paper reports the development of a test device for replicating unique features of concussion-causing helmet-to-ground impacts. Helmet-to-ground impacts are characterized by an oblique impact velocity vector, preimpact rotational motion of the helmeted head, and an impact into a compliant frictional surface of unknown effective mass. No helmet assessment testing program replicates these impact characteristics, yet they influence brain injury risk and therefore may influence helmet design priorities. To replicate these mechanics, the carriage of a drop tower was modified by the addition of a curvilinear bearing track and a hinged torso-neck fixture to which a helmeted head of a Hybrid III anthropomorphic test device was mounted. Preimpact rotational motion of the head was imparted by forcing a link arm to follow the curvilinear path as the carriage fell under gravity. At impact, the rotating helmeted head struck a vertically mounted surface. The ground impact features of head kinematics are illustrated by comparing rear impacts into a rigid, low-friction surface against those into a compliant frictional surface simulating turf. With the rigid, low-friction surface, the head experienced a change in rotational rate of approximately 40 rad/s, which corresponded to a peak rotational acceleration of approximately αy = - 4000 rad/s2. In contrast, peak rotational acceleration with the compliant frictional surface was approximately αy = - 1000 rad/s2 while the helmet was in contact with the surface. Neck loads were significantly greater with the compliant frictional surface. Translational head acceleration was less sensitive to the surface characteristics, with the peak of the anterior-posterior component essentially unchanged.

Neck injury mechanisms in train collisions: Dynamic analysis and data mining of the driver impact injury.

Human necks are vulnerable in train collision accidents. To design a safer cab workspace, the driver neck injury mechanism should be investigated first. In this study, this issue is addressed by investigating how neck injuries are influenced by the cab workspace dimensions. The driver-console-seat dynamic models are developed to quantify the neck injuries. The three-pivot head-neck-upper torso model is used to evaluate the relative rotation angle between head and upper torso (ß+γ). The injury mechanism with the larger (ß+γ) value results in more severe neck injuries. The decision tree model is established to explore the most important cab workspace dimensional parameter. The driver submarining posture (the driver exhibits the tendency of sliding down from the seat after contacting the console) generates more (ß+γ) value than the flipping over behavior (the driver contacts the console and the upper body continues to move over the top of the console). Four neck injury mechanisms are classified, in which the chest-first impact mechanisms are more dangerous than the knee-first impact mechanisms. The distance between the console edge and knee bolster has the greatest effect on the neck injury. This parameter determines the injury mechanism type as it influences the first contact region of the driver. The distance between the console and seat and the pedal height are the secondary dominant attributes. These three parameters should be considered preferentially for establishing driver protection measures.

A decade of head, neck and facial cricket injury hospitalisations in Victoria, Australia: From 2007/08 to 2016/17.

OBJECTIVES: To present an epidemiological profile of hospital-treated head, neck and facial cricket injuries from 2007/08 to 2016/17 in Victoria, Australia. DESIGN: Retrospective analysis of emergency department and hospital admission data. METHODS: An analysis of Victorian hospital-treated head, neck and facial cricket injuries of all cricket participants over 5 years old between July 2007 and June 2017. RESULTS: Over the decade, 3907 head, neck, facial (HNF) cricket injuries were treated in Victorian hospitals. The number of HNF cricket injuries substantially increased in the 2014/15 season from 367 to 435 injuries and remained over 400 in the subsequent years. More injuries were reported for male compared to female participants, 3583 compared to 324 injuries. When adjusted for participation in competitive cricket, the injury incidence rate was 1.3 per 1000 participants for males and 0.4 per 1000 participants for females. The 10-14year age group most frequently required hospital treatment. Open wounds were the most common type of injury (1166, 29.8%) and the main mechanism for HNF cricket injury for this decade was hit/struck/crush (3361, 86.0%). CONCLUSIONS: This study provides a novel and current insight of the incidence and details of HNF injuries among cricket participants in Victoria over a decade. It is evident that males and younger participants, regardless of gender, have a higher risk of sustaining a HNF injury. This study provides a solid evidence base for stakeholders in developing strategies to minimise head, neck and facial injuries to make cricket a safe sport for all.

A novel Cervical Spine Protection device for reducing neck injuries in contact sports: design concepts and preliminary in vivo testing.

Head and neck injuries are common in contact sports such as American football. Different mechanisms can produce such injuries, including compressive impact forces on the crown of the helmet with the neck in a flexed chin-down position. The aim of this paper was developing and testing a novel Cervical Spine Protection Device (CSPD) designed to keep the neck within its safe physiological range. The cervical spine range of motion (ROM) of ten participants was measured under four conditions: free; wearing a football gear; wearing the CSPD; and wearing the CSPD underneath the gear. The CSPD was tested in terms of passive and active restraint of head motion, and for its capability to improve endurance time of the neck extensor muscles. Wearing the CSPD resulted in a significant 40-60% reduction in ROM across the three anatomical planes, and in increased endurance of the neck extensor muscles (FREE: 114 ± 57 s; CSPD: 214 ± 95 s; p = 0.004). In quasi-static loading conditions the CSPD was capable of keeping the neck within its physiological range, thus it may be used to decrease the risk of severe injuries due to dangerous chin-down positions.

Head and Neck Injuries Associated With Cell Phone Use.

Importance: As cell phones gain more influence in daily life, they also become potentially more hazardous. Injuries resulting from cell phone use have long been reported largely in the context of driving-related incidents, but other mechanisms of injury have been underreported. Objective: To assess the incidence, types, and mechanisms of head and neck injuries associated with cell phone use. Design, Setting, and Participants: Retrospective cross-sectional study using data from a national database of individuals with head and neck injuries related to cell phone use who presented to emergency departments in the United States between January 1998 and December 2017. Main Outcomes and Measures: Incidence, types, and mechanisms of injury related to cell phone use in the US population. Results: A reported total of 2501 patients (1129 [55.0%] female, 795 [38.8%] white, and 772 [37.6%] aged 13-29 years) presented with injuries of the head and neck related to cell phone use; the estimated weighted national total was 76 043 patients (42 846 females [56.3%], 34 894 [45.9%] white, and 29 956 [39.4%] aged 13-29 years). The most commonly reported subsites of injuries in the head and neck region included the head (33.1% of estimated total); face, including eyelid, eye area, and nose (32.7%); and neck (12.5%). The most common injury diagnoses included laceration (26.3% of estimated total), contusion/abrasion (24.5%), and internal organ injury (18.4%). Age group distributions showed that most injuries associated with cell phone user distraction occurred among individuals aged 13 to 29 years (60.3%; Cramer V = 0.29). In addition, those younger than 13 years were significantly more likely to sustain direct mechanical injury from a cell phone (82.1%) than to have a cell phone use-associated injury (17.9%) (Cramer V = 0.305), whereas a cell phone use-associated injury was more likely than a direct mechanical injury to occur among those aged 50 to 64 years (68.2% vs 31.8%; Cramer V = 0.11) and those older than 65 years (90.3% vs 9.7%; Cramer V = 0.29). Conclusions and Relevance: Cell phone-related injuries to the head and neck have increased steeply over the recent 20-year period, with many cases resulting from distraction. Although the disposition of most cases is simple, some injuries bear a risk of long-term complications. Many of these injuries occurred among those aged 13 to 29 years and were associated with common activities, such as texting while walking. These findings suggest a need for patient education about injury prevention and the dangers of activity while using these devices.

Responses of the scaled pediatric human body model in the rear- and forward-facing child seats in simulated frontal motor vehicle crashes.

Objective: The study presents the first-ever endeavor at developing 18-, 24-, 30-, 36-, 42-, and 48-month-old pediatric finite element models from the 6-year-old PIPER human body model as a baseline and comparing their responses systematically in rear-facing and forward-facing simulations across similar boundary conditions.Methods: A 6-year-old PIPER model was scaled down to create anthropometric models of the 18-, 24-, 30-, 36-, 42-, and 48-month-old child using the PIPER scaling tool. The models were installed on a convertible car seat (rear-facing and forward-facing configurations) installed with a 3-point lap-shoulder belt in the rear outboard seat of a 2012 Toyota Camry vehicle model finite element model and setup for full-frontal crash simulation (24 G, 120 ms pulse).Results: The forward-facing models showed higher head resultant accelerations for 24-, 36-, 42-, and 48-month-old models (reduction for rear-facing seats ranging from 10% to 32%). For the 18- and 30-month-old models, the maximum head acceleration showed similar values (difference of less than 10%). Upper neck forces and moments were consistently lower for rear-facing models compared to forward-facing. The neck forces were reduced by 83%-90% and the neck moments were reduced by 63%-85% in the rear-facing models compared to their respective forward-facing configurations. The reduction in head injury criterion (HIC36) for rear-facing models ranged from 14% to 51%. The neck injury criterion (Nij) for all forward-facing models was 6 to 9 times the values of their rear-facing counterpart.Conclusions: The study shows the potential benefit of rear-facing orientation compared to forward-facing for children up to 4 years of age in a controlled environment.

Helmet use and bicycle-related trauma injury outcomes.

Background: It is essential to identify factors that predict helmet use, so as to mitigate the injury and mortality from bicycle accidents.Objective: To examine the relationship between helmet use and the bicycle-related trauma injury outcomes among bicyclists with head/neck injury in the US.Methods: Data from the 2002-2012 National Trauma Data Bank were used, including all trauma bicycle riders involved in bicycle-related accidents whose primary reason for the hospital or Intensive Care Unit stay was head or neck injury. Using multiple logistic regression, the association between helmet use, Injury severity score (ISS), length of stay in hospital (HLOS) and Intensive Care Unit (ICULOS), and mortality was examined.Results: Of the 76,032 bicyclists with head/neck injury, 22% worn helmets. The lowest was among Blacks, Hispanics, and <17 years old. Wearing a helmet significantly reduces injury severity, HLOS, ICULOS, and mortality (i.e total and in-hospital). Males had a severe injury, longer HLOS, ICULOS, and higher mortality than female. Blacks and Hispanics had longer HLOS and ICULOS and higher total mortality than Whites, but had a similar chance for in-hospital mortality.Conclusions: More effort is needed to enhance helmet use among at-risk bicycle riders, which may reduce injury severity, HLOS, ICULOS, and mortality.

Biomechanical study of the thyroid cartilage: A model of bi-digital strangulation.

The presence of fracture on neck elements is an indication of violence. Both the hyoid bone and the larynx can be damaged by a strangulation mechanism. Thyroid cartilage, more specifically, may present lesions in response to this mechanical stress. These lesions result in fractures at the bases of the horns of the thyroid cartilage. This study focuses on the thyroid cartilage behavior in cases of bi-digital strangulation, using an anthropometric and biomechanical approach. To develop a biomechanical model, we performed an anthropometric study taking into account 14 distances measurements as well as 3 measurements of angles. These measures allowed us to determine a significant sexual dimorphism between individuals. Then, we define 6 morphologies models, composed of 3 females and 3 males individuals. In order to visualize the ossification of the cartilage, each model has been tested with bone properties. Strangulation cases were simulated by applying an imposed velocity of 0.4m/s then 1m/s. We observed different behaviors of the thyroid cartilage according to the sex and the morphology.

Helmet use is associated with higher Injury Severity Scores in alpine skiers and snowboarders evaluated at a Level I trauma center.

BACKGROUND: There is uncertainty regarding the efficacy of ski helmets in preventing traumatic injury. We investigated the relationship between helmet use, injury types, and injury severity among skiers and snowboarders. METHODS: The trauma registry at a Northeast American College of Surgeons Level I trauma center was queried by International Classification of Diseases Codes-9th or 10th Revision for skiing and snowboarding injury between 2010 and 2018. The primary exposure was helmet use and primary outcome was severe injury (Injury Severity Score >15). We performed univariate and multivariable logistic regression to assess for injury types and severity associated with helmet use. RESULTS: Seven hundred twenty-one patients (65% helmeted, 35% unhelmeted) met inclusion criteria. Helmet use doubled during the study period (43% to 81%, p < 0.001), but the rate of any head injury did not significantly change (49% to 43%, p = 0.499). On multivariable regression, helmeted patients were significantly more likely to suffer severe injury (odds ratio [OR], 2.01; 95% confidence interval [CI], 1.30-3.11), intracranial hemorrhage (OR, 1.81; 95% CI, 1.10-2.96), chest injury (OR, 1.66; 95% CI, 1.05-2.61), and/or lumbosacral spine injury (OR, 1.84; 95% CI, 1.04-3.25) than unhelmeted patients. Helmeted patients were half as likely to suffer cervical spine injury (OR, 0.51; 95% CI, 0.30-0.89) and a third as likely to sustain skull fracture and/or scalp laceration (OR, 0.30; 95% CI, 0.14-0.64). More patients who hit a stationary object were helmeted compared with those who fell from standing height onto snow (70% vs. 56% respectively, p < 0.001). After adjustment, hitting a stationary object was the injury mechanism most significantly associated with severe injury (OR, 2.80; 95% CI, 1.79-4.38). CONCLUSION: Helmeted skiers and snowboarders evaluated at a Level I trauma center were more likely to suffer severe injury, including intracranial hemorrhage, as compared with unhelmeted participants. However, they were less likely to sustain skull fractures or cervical spine injuries. Helmeted patients were also more likely to hit a stationary object. Our findings reinforce the importance of safe skiing practices and trauma evaluation after high-impact injury, regardless of helmet use. LEVEL OF EVIDENCE: Prognostic and epidemiological, level IV.

Alpine Skiing Injuries.

CONTEXT:: Alpine skiing is a popular sport worldwide but has significant risk for injury. The epidemiology of skiing-related injuries has been described, which has led to the identification of risk factors for specific types of injuries. EVIDENCE ACQUISITION:: Pertinent literature from peer-reviewed publications was reviewed. STUDY DESIGN:: Clinical review. LEVEL OF EVIDENCE:: Level 5. RESULTS:: The adoption of international standards for ski-boot-binding systems has changed the profile of skiing-related injuries over time, as has the widespread use of helmets. An understanding of mechanisms of injury, risk factors, and preventative measures may decrease the incidence of skiing-related injuries. CONCLUSION:: Advances in standards for skiing equipment have been effective at decreasing both the frequency and severity of skiing-related injuries, but additional efforts are required to improve the safety of the sport.

Comparación biomecánica de la autoextracción con y sin collarín cervical: estudio de simulación / Self-extraction with and without a cervical collar: a biomechanical simulation study

Objetivos: Comparar la autoextracción (AE) frente a la AE con collarines en sujetos con bajo riesgo de lesión cervical. Método: Estudio de simulación mediante análisis biomecánico con sensores inerciales, determinando la desalineación de la columna cervical durante la AE con y sin collarines cervicales. Resultados: El desequilibrio fue 3,12 (DE 34,62) grados mayor con el collarín STIFNECK (SN) (IC al 95% de -15,33 a 21,57; p =0,7234) que con AE y también 5,95 (DE 31,76) grados mayor con collarín X-COLLAR (XC) (IC al 95% de -10,98 a 22,87; p = 0,4654) que con AE. Cuando comparamos la AE con los diferentes tipos de collarines, observamos que con el collarín XC se produjeron 2,83 (DE 12,10) grados de desalineación más que con el collarín SN (IC al 95% de -3,62 a 9,27; p = 0,3650). Conclusiones: La desalineación de la columna cervical mediante la AE es similar a la provocada cuando se aplican collarines cervicales

Objective: To compare self-extraction with and without a cervical collar in subjects at low risk of cervical spine injuries. Methods: Simulation study analyzing biomechanical data from inertial sensors to detect misalignment of the cervical spine during self-extraction with and without a cervical collar. Results: Misalignment was a mean (SD) 3.12 (34.62) degrees greater during self-extraction with a Stiffneck collar in place (95% CI, -15.33 to 21.57 degrees; P=.7234) than during extraction without a collar. Misalignment was also greater, by 5.95 (31.76) degrees, with an X-collar in place (95% CI, -10.98 to 22.87; P=.4654) than without a collar. The between-collar comparison of differences showed that misalignment was 2.83 (12.10) degrees greater with the X-collar (95% CI, -3.62 to 9.27 degrees; P=.3650). Conclusion: Misalignment of the cervical spinal column is similar during self-extraction with or without a cervical collar in place