A new probabilistic model: Theory, simulation and applications to sports and failure times data.

In applied sectors, data modeling/analysis is very important for decision-making and future predictions. Data analysis in applied sectors mainly relies on probability distributions. Data arising from numerous sectors such as engineering-related fields have complex structures. For such kinds of data having complex structures, the implementation of classical distributions is not a suitable choice. Therefore, researchers often need to look for more flexible models that might have the capability of capturing a high degree of kurtosis and increasing the fitting power of the classical models. Taking motivation from the above theory, to achieve these goals, we study a new probabilistic model, which we named a new beta power flexible Weibull (NBPF-Weibull) distribution. We derive some of the main distributional properties of the NBPF-Weibull model. The estimators for the parameters of the NBPF-Weibull distribution are derived. The performances of these estimators are judged by incorporating a simulation study for different selected values of the parameters. Three data sets are used to demonstrate the applicability of the NBPF-Weibull model. The first data set is observed from sports. It represents the re-injury rate of various football players. While the other two data sets are observed from the reliability zone. By adopting certain diagnostic criteria, it is proven that the NBPF-Weibull model repeatedly surpasses well-known classical and modified models.

The role of public policy in reducing moped and scooter injuries in South Carolina.

INTRODUCTION: Mopeds and electric scooters have grown in popularity in recent years. A South Carolina (SC) law was passed on November 19, 2018, aimed to regulate mopeds and scooters. This study aims to evaluate whether this SC law was associated with a decrease in the moped injury rate in a Level 1 Trauma Center. METHODS: A retrospective review of trauma registry data was used to identify a cohort of patients 14 years and older who came to a Level 1 trauma center for a moped/scooter accident between January 2014 - December 2022. The proportion of moped injuries before and after the passing of the law was calculated. The chi-square test and Wilcoxon Rank Sum test were used to compare differences in proportions for categorical factors and continuous factors, respectively. RESULTS: A total of 350 moped injury cases were identified. There was a significant decrease in the moped injury rate after the passing of the 2018 SC law (0.9 % vs 1.8 %, p<0.001). Additionally, those treated post-law implementation were significantly older (47.4 vs 43.2 years, p = 0.013) and more likely to be male (95.5 % vs 87.9 %, p = 0.025) than those treated pre-law. Patients treated post-law were significantly more likely to be uninsured (45.1 % vs 42.7 %, p = 0.009) and less likely to have commercial (16.2 % vs 20.1 %, p = 0.009), or government (29.7 % vs 35.6 %, p = 0.009) health insurance compared to those treated pre-law. There was no significant difference between the two groups in Glascow Coma Scale, Injury severity score, Trauma Injury Severity Score, or rate of fatalities. CONCLUSION: After the implementation of a SC law, we found that the local proportion of injuries due to moped and scooter accidents was significantly lower than pre-law proportions. These findings suggest that public policies aimed at increasing regulations for mopeds may decrease the rate of injury, but not severity, from moped use.

Acute occupational inhalation injuries-United States, 2011-2022.

BACKGROUND: Inhalation injuries due to acute occupational exposures to chemicals are preventable. National surveillance of acute inhalation exposures is limited. This study identified the most common acute inhalation exposure-related incidents by industry sector among US workers. METHODS: To characterize inhalation-related injuries and their exposures during April 2011-March 2022, state and federal records from the Occupational Safety and Health Administration (OSHA) Occupational Safety and Health Information System (OIS) accident database were analyzed. Industry-specific injury, hospitalization, and fatality rates were calculated. RESULTS: The most frequent acute inhalation incidents investigated by OSHA were caused by inorganic gases (52.9%) such as carbon monoxide (CO) or acids, bases, and oxidizing chemical agents (12.9%) such as anhydrous ammonia. The largest number of fatal and nonfatal injuries were reported in the manufacturing (28.6%) and construction (17.2%) sectors. CONCLUSIONS: Workers were affected by acute inhalation exposures in most industries. Using this surveillance, employers can recognize frequently-occurring preventable acute inhalation exposures by industry, such as inorganic gases in the manufacturing sector, and implement prevention measures. Training of workers on exposure characteristics and limits, adverse health effects, and use of protective equipment by exposure agent can prevent inhalation injuries.

Laparoscopic Cholecystectomy Versus Open Cholecystectomy in Acute Cholecystitis: A Literature Review.

Cholecystectomy is a common surgical procedure performed worldwide for acute cholecystitis. Acute cholecystitis occurs when the cystic duct is obstructed by a gallstone, which causes gallbladder distension and subsequent inflammation of the gallbladder. Acute cholecystitis is characterized by pain in the right upper quadrant, anorexia, nausea, fever, and vomiting. Cholecystectomy is the treatment of choice for acute cholecystitis. The two commonly performed types of cholecystectomies are open cholecystectomy and laparoscopic cholecystectomy. However, the approach of choice widely fluctuates with regard to various factors such as patient history and surgeon preference. It is imperative to understand the variations in outcomes of different approaches and how best they fit an individual patient when deciding the technique to be undertaken. This article reviews several studies and compares the two techniques in terms of procedure, mortality rate, complication rate, bile leak/injury rate, conversion rate, and bleeding rate.

The effects of high-velocity hamstring muscle training on injury prevention in football players.

Background: Explosive and fast body movements, sprints, jumps and quick changes of direction, which are characteristic of the football training, place considerable strain on the hamstring muscles. Due to the high occurrence of hamstring injuries, new preventive strategies are required that focus on high-velocity training. The purpose was to assess the effectiveness of high-velocity elastic-band training in reducing the occurrence of hamstring injuries in football players. Methods: Male football players from 15 teams (n = 319) playing in national competitions participated in this study. The players were involved in a 5-week exercise period in either the intervention group (INT) or the control group (CON), with a follow-up period of ∼4 months where hamstring injuries and exposure time were recorded. The INT group had two to three sessions per week of elastic-band training with low-load, high-velocity leg curls while lying prone; the CON group performed self-paced football-specific drills. Results: The incidence rate of hamstring injuries was 6.5% in the INT group (8 out of 123 players) and 9.2% in the CON group (18 out of 196 players). Although the INT group showed almost 1/3 reduction in hamstring injury incidence compared to the CON group, the difference was not statistically significant (p > 0.05). Moreover, no differences (p > 0.05, odds ratio [OR] = trivial-to-small) in distribution between the groups were found in hamstring injury characteristics (leg dominance and mechanism) except for the distribution of injuries that occurred during matches or training (p = 0.036; OR = 6.14, moderate). Conclusion: The program of high-velocity elastic-band training did not prove to be effective in preventing hamstring muscle injuries in football players despite displaying some positive indications that could be considering when creating injury prevention programs.

Descriptive Epidemiology of Game-Related Youth Flag Football Injuries.

CONTEXT: Flag football is promoted as a safer alternative to tackle football. This may be 1 reason why participation rates have risen by 39% over the past 3 years. Despite rising participation, epidemiologic research on sport-specific injuries and associated relative risk is lacking. OBJECTIVE: To prospectively document the epidemiology of injuries in youth flag football. DESIGN: Descriptive epidemiology study. SETTING: Regional and national youth flag football tournaments. PATIENTS OR OTHER PARTICIPANTS: Athletes (N = 1939; 1744 boys and 195 girls), ages 6 to 12 years. An athletic trainer prospectively monitored the athletes for sport-related injury and exposures. MAIN OUTCOME MEASURE(S): Athlete risks of injury and injury rates were calculated overall and by sex. Injury characteristics were reported for the total population and by sex. RESULTS: Forty-seven injuries to unique individuals were recorded in 1939 athletes with a total of 9228 athlete-exposures (AEs). The overall risk of injury was 2.4% (95% CI = 1.79%, 3.21%), with an overall injury rate of 5.1 per 1000 AEs (95% CI = 3.75, 6.77). Of the 47 injuries, 36 occurred in boys (8365 AEs), and 11 occurred in girls (863 AEs). A higher risk in girls was evidenced by both the injury risk ratio (2.73; 95% CI = 1.41, 5.30) and injury rate ratio of 2.96 (95% CI = 1.51, 5.82). The most common injury sites were the head/face/neck (n = 15, 31.9%), followed by the ankle/foot (n = 9, 19.1%). The most frequent types of injury were contusion (55.3%), sprain/subluxation (14.9%), and general trauma (10.6%); 74.5% of all injuries resulted from direct impact. CONCLUSIONS: Although the competition injury rate for youth flag football was lower than the values from studies reporting comparable tackle football data, the frequencies by body part, type, and mechanism were similar. Given that most injuries were related to some form of impact and predominantly contusions, adopting minimal protective equipment or padding may reduce the numbers of these injuries.

Effectiveness of Injury Prevention Programs With Core Muscle Strengthening Exercises to Reduce the Incidence of Hamstring Injury Among Soccer Players: A Systematic Review and Meta-Analysis.

CONTEXT: Muscles in the hamstring group are frequently injured in sporting activities. Injury prevention programs (IPPs), including eccentric training of the hamstrings, have proven to be of great value in decreasing the injury rate of hamstring muscles. OBJECTIVE: To examine the effectiveness of IPPs that include core muscle strengthening exercises (CMSEs) in reducing hamstring injury rates. DATA SOURCES: This systematic review with meta-analysis was based upon the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A systematic search was conducted for relevant studies published from 1985 to 2021 using the following databases: Cochrane Library, MEDLINE, AMED, PubMed, Web of Science, and Physiotherapy Evidence Database (PEDro). STUDY SELECTION: The initial electronic search found 2694 randomized controlled trials (RCTs). After removing duplicate entries, 1374 articles were screened by their titles and abstracts, and 53 full-text records were assessed, of which 43 were excluded. The remaining 10 articles were reviewed in detail, from which 5 studies met our inclusion criteria and were included in the current meta-analysis. STUDY DESIGN: Systematic review and meta-analysis of RCTs. LEVEL OF EVIDENCE: Level 1a. DATA EXTRACTION: Two researchers independently completed the abstract review and performed full-text reviews. A third reviewer was consulted to reach a consensus if any discrepancies were noted. Details were recorded about the participants, methodological aspects, eligibility criteria, intervention data, and outcome measures, including age; number of subjects in the intervention/control group; number of injuries in each group; and the duration, frequency, and intensity of the training conducted in the intervention. RESULTS: The pooled results of 4728 players and 379,102 exposure hours showed 47% hamstring injury reduction per 1000 h of exposure in the intervention group compared with the control group with an injury risk ratio of 0.53 (95% CI [0.28, 0.98], P = 0.04). CONCLUSION: The results indicate that CMSEs incorporated with IPPs reduce susceptibility and risk of hamstring injuries in soccer players.

Spinal injury rates and specific causation in motor vehicle collisions.

Motor vehicle collisions (MVCs) are a leading cause of acute spinal injuries. Chronic spinal pathologies are common in the population. Thus, determining the incidence of different types of spinal injuries due to MVCs and understanding biomechanical mechanism of these injuries is important for distinguishing acute injuries from chronic degenerative disease. This paper describes methods for determining causation of spinal pathologies from MVCs based on rates of injury and analysis of the biomechanics require to produce these injuries. Rates of spinal injuries in MVCs were determined using two distinct methodologies and interpreted using a focused review of salient biomechanical literature. One methodology used incidence data from the Nationwide Emergency Department Sample and exposure data from the Crash Report Sample System supplemented with a telephone survey to estimate total national exposure to MVC. The other used incidence and exposure data from the Crash Investigation Sampling System. Linking the clinical and biomechanical findings yielded several conclusions. First, spinal injuries caused by an MVC are relatively rare (511 injured occupants per 10,000 exposed to an MVC), which is consistent with the biomechanical forces required to generate injury. Second, spinal injury rates increase as impact severity increases, and fractures are more common in higher-severity exposures. Third, the rate of sprain/strain in the cervical spine is greater than in the lumbar spine. Fourth, spinal disc injuries are extremely rare in MVCs (0.01 occupants per 10,000 exposed) and typically occur with concomitant trauma, which is consistent with the biomechanical findings 1) that disc herniations are fatigue injuries caused by cyclic loading, 2) the disc is almost never the first structure to be injured in impact loading unless it is highly flexed and compressed, and 3) that most crashes involve predominantly tensile loading in the spine, which does not cause isolated disc herniations. These biomechanical findings illustrate that determining causation when an MVC occupant presents with disc pathology must be based on the specifics of that presentation and the crash circumstances and, more broadly, that any causation determination must be informed by competent biomechanical analysis.

Trends in pediatric baseball and softball injuries presenting to emergency departments.

BACKGROUND: Millions of youth participate in baseball and softball in the United States and these youth account for a large number of pediatric sports injuries. This study sought to characterize annual, seasonal, and age-related trends in pediatric softball and baseball injuries presenting to the Emergency Department (ED). METHODS: The National Electronic Injury Surveillance System (NEISS) database was retrospectively examined for all softball and baseball injuries from 2010 to 2019 involving pediatric patients aged 7-21 years. Patients were classified by age as children (ages 7-13), adolescents (ages 14-18), or young adults (ages 19-21). Case narratives were used to assign mechanisms of injury. National injury estimates were calculated using statistical weights provided by the Consumer Product Safety Commission. RESULTS: An estimated 1,372,573 pediatric softball and baseball ED visits occurred from 2010 to 2019. The mean age of the patient population was 13.6 years old (95% CI = 13.5-13.8 years), and baseball athletes were younger than softball athletes (13.2 years and 14.3 years) (p < 0.01). Moreover, baseball athletes hit by the bat were younger than their softball counterparts (11.8 years and 13.4 years). Most baseball and softball injuries were the result of being hit by the ball (52.8% and 54.2%) or sliding into a base (13.1% and 15.8%). The annual number of injuries decreased during the studied time period by 41.1% for baseball injuries and by 38.3% for softball injuries. The annual number of injuries related to all injury mechanisms decreased over the studied time period for both sports, with the exception of baseball throwing injuries, which increased by 8.6%. Baseball and softball injuries were both most likely to be present to the ED on Sunday (16.3% and 17.9%) and during the Spring (53.2% and 55.3%). CONCLUSION: Safety guidelines should focus on reducing the prevalence of injuries acquired by younger baseball and softball players during practice and educating coaches and players on existing pitch count guidelines.

High rate of muscle injury despite no changes in physical, physiological and psychophysiological parameters in a professional football team during a long-congested fixture period.

This study aimed to analyse match availability, participation, and muscle injury incidence and to compare the effect of time intervals between matches (3-4 versus 6-7 days) on physical, physiological, and psychophysiological parameters in a professional football team during a prolonged congested fixture period. Thirteen professional male football players (29.2 ± 4.8 years old; 78.5 ± 8.3 kg; 179.3 ± 8.8 cm;) participated. Data were collected during 17 consecutive weeks for 35 official matches separated by an average interval of ≤ 3.5 days. Results showed a player availability of 84.8 ± 16.1% while match participation was 68.8% ± 6.4%. Muscle injury incidence was 19.0/ 1,000 hours of match exposure. These injuries occurred after individual players participated in sequences of 8.3 ± 3.3 consecutive matches with intervals of 3.8 ± 0.8 days. No differences were observed in physical performance or in fatigue-related parameters irrespective of the time interval between matches. A high player availability rate was observed. No differences were observed in physical, physiological, and psychophysiological indices of performance when comparing shorter and longer time intervals between consecutive matches.Prolonged exposure to fixture congestion resulted in an high risk of incurring muscle injury.

Comparisons of musculoskeletal injuries among three different modalities of Taekwondo (Kyorugi, Poomsae, and Shibum): a one-year follow-up prospective epidemiologic study.

The purpose of the study was to report the injury rates and characteristics (body location, type, mechanism, and severity) of musculoskeletal injuries in Kyorugi, Poomsae, and Shibum. A total of 137 Korean collegiate Taekwondo players - Kyorugi (n = 44), Poomsae (n = 46), and Shibum (n = 47) - were prospectively studied in 2019. Injury rates per 1,000 athlete-exposures (AEs) and time-exposures (TEs) during training and competition were calculated. Additionally, body location, type, mechanism, and severity of injury were analysed. The highest injury rate was recorded in Poomsae (172.0/1,000 AEs and 79.5/1,000 TEs) followed by Kyorugi (47.1/1,000 AEs and 25.9/1,000 TEs) and Shibum (57.5/1,000 AEs and 17.0/1,000 TEs). The frequently injured body location was the thigh (Kyorugi = 17%; Poomsae = 25%; Shibum = 18%). The common injury types were muscle cramps/spasms in Kyorugi (33%) and Poomsae (59%), and sprain in Shibum (41%). The common injury mechanisms were gradual onset in Kyorugi (40%) and Shibum (49%), and non-contact trauma in Poomsae (91%). Regarding the severity, the number of days from the injury onset to recovery > 1 week were higher in the order of Kyorugi (78%), Shibum (54%), and Poomsae (28%). Our data provide preliminary evidence that different injury prevention strategies should be applied to each modality of Taekwondo.

The Injury Rate in NBA Players Did Not Increase Following Return to Play After the COVID-19 Stay-at-Home Order.

OBJECTIVE: The purpose of this study was to investigate the injury rate in NBA players following return to play during the post-COVID-19 shutdown 2019-2020 NBA season. METHODS: This study was a retrospective review of all NBA players who were placed on the injury report during the preseason and first 4 weeks of the regular season as well as playoffs from the 2017-2018 through 2020-2021 NBA seasons. The data were compiled using publicly available injury reports. All injuries were recorded, and injury rates were calculated per 1000 athletic exposures. Risk ratio with 95% confidence intervals compared injury rates between the 2 cohorts. RESULTS: Over the course of the study period, 399 injuries were reported. The highest injury rate per athletic exposure was observed to have occurred during the first month of the regular season in the 2 seasons prior to the COVID-19 pandemic. There was no significant difference in the average number of games missed before and after the pandemic for the preseason (P = .95), first month of regular season (P = .62), and playoffs (P = .69). There was no significant difference in the rate of injury when comparing injury rates before and after the pandemic for the preseason (P = .25), first month of the regular season (P = .11), and playoffs (P = .3). CONCLUSION: The rate of injury in NBA players following the COVID-19 pandemic was not significantly higher than 2 recent past NBA seasons.

Causal effects, workload and injury risk: The importance of specifying the research question.

OBJECTIVES: To illustrate why the research question determines whether and how sport medicine investigators should adjust for workload when interested in interventions or causal risk factors for injury. DESIGN: Theoretical conceptualization. METHODS: We use current concepts of causal inference to demonstrate the advantages and disadvantages of adjusting for workload through different analytic approaches when evaluating causal effects on injury risk. RESULTS: When a risk factor of interest changes workload, including workload in the regression will cause bias. When workload represents time-at-risk (e.g. games played, minutes run), including workload as an offset in Poisson regression provides a comparison of injury rates (injuries per unit time). This is equivalent to including log(workload) as an independent variable with the coefficient fixed to 1. If workload is included as an independent variable instead of an offset, using log(workload) rather than workload is more consistent with theory. This practice is similar to the principles of allometric scaling. When workload represents a combination of both time-at-risk and intensity, such as with session ratings of perceived exertion, the optimal analytical strategy may require modeling time-at-risk and intensity separately rather than as one factor. CONCLUSIONS: Whether to account for recent workload or not, and how to account for recent workload, depends on the research question and the causal assumptions, both of which should be explicitly stated.

Do Injury Rates in Position Players Who Convert to Pitchers in Professional Baseball Differ From Players Who Have Always Been Pitchers?

BACKGROUND: There are some professional baseball players who begin their career as a position player and later convert to a pitcher; injury rates in these players are unknown. PURPOSE: To compare injury rates of professional baseball players who started their career as position players and converted to pitchers with a control group of pitchers who have been only pitchers throughout their professional career. HYPOTHESIS: Injury rates would be lower in the conversion players. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: All players who began their professional baseball career as position players and converted to pitchers between 2011 and 2018 were included. All injuries that occurred after they converted to pitchers were included. The conversion players were matched 1 to 1 with a control group of pitchers who entered professional baseball as pitchers and never changed position. Injury rates were compared between groups. The performance between groups was also compared. RESULTS: Overall, 221 players were identified who converted from position players to pitchers. There were significantly more injuries per year in the control pitcher group (0.8 ± 0.9) than in the conversion pitcher group (0.7 ± 0.9; P = .015). Injuries in the control group resulted in 61 ± 112 days missed per injury, while injuries in the conversion player group resulted in 54 ± 102 days missed per injury (P = .894). Injury characteristics differed between groups. However, in both groups, most of the injuries were related to pitching or throwing, were noncontact or gradual overuse injuries, and involved the upper extremity. Converted pitchers had lower pitcher usage, with fewer games and innings pitched (P < .001), with significantly worse statistics for walks plus hits per inning pitched (P = .018). CONCLUSION: Professional baseball players who convert from position players to pitchers are injured at lower rates than control pitchers. Conversion pitchers have lower pitcher usage, which may contribute to their reduced injury rates.

Epidemiology of Sports-Related Injuries and Associated Risk Factors in Adolescent Athletes: An Injury Surveillance.

The present study aimed to determine the epidemiology of sport-related injuries in amateur and professional adolescent athletes and the incidence of different risk factors on those injuries. Four hundred ninety-eight athletes aged 14 to 21 voluntarily participated in this prospective injury surveillance, conducted from 1 January 2019 to 31 December 2019. The information collected included: personal data, sports aspects, characteristics of the injuries, and lifestyle. Forty point four percent of the participants suffered an injury in 2019 (39% of them in a previously injured area). The average injury rate was 2.64 per 1000 h. Soccer presented the highest rate (7.21). The most common injuries were: lumbar muscle strains (12.24%), ankle sprains (11.98%), and bone fractures (9.31%). Ankles (36.12%), knees (19.32%), and shoulders (6.47%) concentrated the highest number of injuries. Fifty-nine point twenty-eight percent of the injuries occurred during practices, and 40.72% during competition or peri-competition. Higher injury rates were associated (in this order) with the following factors: (a) Greater number of hours of practice per week. (b) Not performing warm-ups. (c) Using inadequate sports facilities. (d) Being aged 14-17. (e) Not performing physical preparation. (f) Inappropriate training load. (g) Not performing injury-preventive activities. (h) Performing sports technique without the supervision of one sports coach. (i) Inadequate sports equipment. In conclusion, since most injury risk factors are modifiable, it is imperative to implement strategies to reduce amateur and professional adolescent athletes' injury rates.

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.

Rear-seat occupant demographics in rear impacts: Analysis of NASS-CDS.

PURPOSE: This study analyzes field accidents to identify rear-occupant exposure and injury by crash types. Occupant demographics and injury were assessed by body region and crash severity to understand rear-occupant injury mechanisms in rear crashes. METHODS: The exposure and serious-to-fatal injury was determined by crash type for non-ejected second- and third- row occupants in 1994+ MY vehicles using 1994-2015 NASS-CDS. Selected occupant demographics and serious injury distributions were assessed over a range of delta V for rear crashes. RESULTS: Rear crashes accounted for 8.7% of exposed and 5.4% of serious-to-fatally injured rear-seat occupants. On average, rear-seat occupants were 14.3 ± 1.5 years old (median 10.3, 90th CI 0.08-29.6), weighed 44.7 ± 2.6 kg (median 44.4, 90th CI 7.9-81.7) and were 130.3 ± 4.1 cm tall (median 141.4, 90th CI 67.3-178.4). With serious injury, the average rear occupant was 18.1 ± 5.8 years old (median 13.1, 90th CI 0.0-47.2), weighed 42.6 ± 10.7 kg (median 31.4, 90th CI 7.0-82.4) and was 120.6 ± 15.4 cm tall (median 145.4, 90th CI 48.8-174.1). More than 72% of rear-seat occupants were in delta V less than 24 km/h. Less than 2% were in delta V 48 km/h or greater. The overall rate of serious-to-fatally injured (MAIS 3 + F) was 0.73% ± 0.37%. For serious-to-fatally injured rear-seat occupants, the average delta V was 37.4 ± 3.1 km/h (median 29.8, 90th CI 28.6-62.1). None were involved in delta Vs less than 24 km/h, about 78% were in a delta V between 24-48 km/h and 22% were in a delta V of 48 km/h or greater. Head and chest were most commonly injured, irrespective of crash severity. CONCLUSIONS: The height and weight of a 10-year old and 5th Hybrid III ATD are representative of the average rear-seat occupant involved in rear crashes based on NASS-CDS. Crash tests with a delta V of between 30 and 37 km/h represent the typical collision causing serious-to-fatal injury.

Effect of ABTS and conventional seats on occupant injury in rear impacts: Analysis of field and test data.

PURPOSE: This study addressed the potential effect of higher seat stiffness with ABTS (All-Belt-to-Seat) compared to conventional seats in rear impacts. It analyzed field accidents and sled tests over a wide range in delta V and estimated the change in number of injured occupants if front-seats were replaced with stiffer ABTS. METHODS: The rear-impact exposures and serious-to-fatal injury rates were determined for 15+ year old non-ejected drivers and right-front passengers in 1994+ model year vehicles using 1994-2015 NASS-CDS. More than 50 rear sled tests were analyzed using conventional and ABTS seats. An injury risk was calculated for selected ATD biomechanical responses. The results obtained with the ABTS and conventional seats were compared for matched tests based on head restraint position, ATD size and initial position and delta V. The change in risk was used to estimate the change in injury in the field by adjusting the injury rate by delta V. RESULTS: On average, front seat occupants were 39 years old, weighed 78 kg and were 171 cm tall. About 29.3% of serious-to-fatally injured (MAIS 3 + F) front seat occupants were involved in delta Vs less than 24 km/h and about 28.4% in a delta V of 48 km/h or greater. The average biomechanical response and injury risk in sled tests were higher with an ABTS seat than with a conventional seat. The average maximum injury risk was assessed by delta V groups for conventional and ABTS seats. The relative risk of ABTS to conventional seats was 1.34 in less than 16 km/h, 1.69 in 16-24 km/h, 1.65 in 24-32 km/h, 1.33 in 32-40 km/h, 5.77 in 40-48 km/h and 48.24 in the 56-64 km/h delta V category. The estimated relative risk was 11.90 in 48-56 km/h and 34.11 in 64+ km/h. The number of serious-to-fatally injured occupants was estimated to increase by up to 6.88-times if stiffer ABTS seats replaced conventional seats. CONCLUSIONS: The field data indicate that the 50th percentile male Hybrid III size is representative of an average occupant involved in rear crashes. ABTS seats used in this study are stiffer than conventional seats and increase ATD responses and injury risks over a wide range of crash severities.

Muskuloskeletal injuries in mountain running races: A 5 seasons study.

INTRODUCTION: Mountain running races have grown in popularity in the recent years. Nonetheless, there are few studies on injuries and injury rates. Moreover, these studies have focused on long-distance events such as ultramarathons (>42 km). Therefore, the aim of the present study was to examine the severity, type, and body location of musculoskeletal injuries during 20-42 km mountain running races. In addition, the injury rates in this type of races were examined. METHODS: Data on injuries were collected during 36 mountain running races over 5 consecutive seasons from 2015 to 2019. The participants reported all musculoskeletal injuries on a standardized injury report form. The results were presented as the number of injuries per 1000 h exposure and per 1000 participants. RESULTS: Twenty eight injuries were reported. Most injuries occurred in the ankle (32%) followed by the knee (14%) and foot/toe (11%). The number of injuries represented an overall injury rate of 1.6 injuries per 1000 h running and 5.9 injuries per 1000 runners. The case fatality rate was 0. CONCLUSIONS: The incidence of musculoskeletal injuries during 20-42 km mountain running races is low. In addition, the majority of injuries experienced by runners are minor in nature and located in lower extremities, mainly the ankles.

Epidemiology of Boys' Club Lacrosse Injuries During the 2018 Summer Lacrosse Season.

CONTEXT: In the past 10 years, participation in boys' youth and high school lacrosse has increased by 33%. Among many club teams and tournaments, athletes may not have access to medical coverage. Additionally, these athletes face a higher volume of play than in traditional scholastic sport settings. OBJECTIVE: To describe the injury characteristics of boys' nonscholastic youth and high school club lacrosse athletes over the course of a summer season. DESIGN: Descriptive epidemiology study. PATIENTS OR OTHER PARTICIPANTS: Boys' nonscholastic youth and high school lacrosse athletes, aged 8 to 18 years, who competed in tournaments. MAIN OUTCOME MEASURE(S): Athletic trainers at tournaments were given standardized injury report forms to document patient encounters. These reports were then entered into the Datalys Injury Surveillance Tool. RESULTS: Over the summer tournament season, 233 injuries were reported in 109 342 athlete-exposures (AEs) for an injury rate of 2.13 per 1000 AEs (95% confidence interval = 1.87, 2.42). The most frequently injured body parts were the head and/or face (n = 51, 22%), arm and/or elbow (n = 34, 15%), and hand and/or wrist (n = 29, 12%). The most common diagnoses were contusions (n = 63, 27%), concussions (n = 44, 19%), fractures (n = 39, 17%), and sprains (n = 35, 15%). The most often injured position was midfielder (n = 65, 41%), followed by defense (n = 48, 30%), attack (n = 36, 23%), and goalkeeper (n = 9, 6%). The concussion rate was 0.4 per 1000 AEs (95% confidence interval = 0.28, 0.52). CONCLUSIONS: The injury rate experienced by boys' nonscholastic club lacrosse athletes was similar to the rates of their high school counterparts as well as school-sponsored football and wrestling athletes. Because of the risk of injury, athletic training services should be available for youth and high school club lacrosse tournaments.