Concussion Incidence Rates Research Articles

Time to Ring in the Body Checking, Head Contact, and Suspected Injury Rates in Youth Ringette: A Video-Analysis Study in Youth Ringette and Female Ice Hockey.

To compare physical contacts (PCs), including head contacts (HCs), suspected concussion, and nonconcussion injury incidence rates between youth ringette and female ice hockey. Cross-sectional. Alberta ice arenas. Players participating in 8 U16AA (ages 14-15 years) ringette and 8 U15AA (ages 13-14 years) female ice hockey games during the 2021 to 2022 season. Dartfish video-analysis software was used to analyze video recordings. Univariate Poisson regression analyses (adjusted for cluster by team-game, offset by game minutes) were used to estimate PCs (including HCs) and suspected injury (concussion and nonconcussion) and concussion-specific IRs and incidence rate ratios (IRRs) to compare sports. Proportions of all PCs that were body checks (level 4-5 trunk PC) and direct HCs (HC1) penalized were reported. Ringette had a 2.6-fold higher rate of body checking compared with hockey (IRR = 2.63, 95% CI: 1.59-4.37). Ringette also had a 2-fold higher rate of HC1 compared with hockey (IRR = 2.08, 95% CI: 1.37-3.16). A 3.4-fold higher rate of suspected injury was found in ringette (IRR = 3.37, 95% CI: 1.40-8.15). There was no significant difference in suspected concussion IRs in ringette compared with hockey (IRR = 1.93, 95% CI: 0.43-8.74). Despite being prohibited in both sports, only a small proportion of body checks (Ringette = 18%; Hockey = 17%) and HC1 (Ringette = 6%; Hockey = 6%) were penalized. Higher rates of body checking, HC1, and suspected injuries were found in ringette compared with female ice hockey. Body checking and HC1 were rarely penalized, despite rules disallowing them in both sports. Future research should consider other youth age groups.

Incidence and Prevalence of Concussion in Denmark from 1999-2018: A Nationwide Cohort Study.

Concussion is a common diagnosis in emergency rooms, yet contemporary incidence and prevalence estimates are sparse and rely on self-reported data. A nationwide cohort study was conducted to provide up-to-date information, covering the entire Danish population from 1999 to 2018. Hospital contacts with a concussion diagnosis, including emergency room visits, hospital admissions, and outpatient contacts, were retrieved from the Danish National Patient Registry (DNPR), and incidence rates were age-standardized and stratified. The 20-year prevalence was defined as the percentage of Danes alive in 2018 who had experienced a concussion since 1999. The diagnostic codes used were the ICD-10 code S06.0 and a local Danish code for 'observation for concussion' (DZ033D). Additional data on activities related to concussion injuries were obtained from the Accident Analysis Group at Odense University Hospital through DNPR. Findings from the study indicated that during the period 1999-2018, the total age-standardized concussion incidence rate increased by 10% to 308 per 100,000 person-years (95% confidence interval (CI): 304-313). Notable time trends included 1) a reduced sex difference from 40% to 6% (95% CI: 3%-9%), 2) a doubled incidence rate in children aged 0-1 and in seniors aged over 80, 3) an increased utilization of head imaging across all age groups, except children, 4) a decline in the proportion of traffic-related concussions, and 5) a prevalence of concussion of 4.9% (95% CI: 4.89% - 4.93%) in 2018. The increasing incidence of concussions among the elderly is concerning in light of an aging population, and warrants further investigation, as evidence-based preventive interventions for falls exist. Additionally, the increased utilization of head imaging across all age groups except children calls for attention toward avoidance of unnecessary radiation exposure. Despite a drop in traffic-related cases, concussions remain highly prevalent. In conclusion, these findings indicate that concussions are an important public health concern, necessitating ongoing surveillance, research, and targeted resource allocation to address concussion management and prevention effectively.

Head Contact and Suspected Concussion Rates in Youth Basketball: Time to Target Head Contact Penalties for Prevention.

To compare game events, head contact (HC) rates, and suspected concussion incidence rates (IRs) in boys' and girls' youth basketball. Cross-sectional. Canadian club basketball teams (U16-U18). Players from 24 boys' and 24 girls' Canadian club basketball teams during the 2022 season. Recorded games were analyzed using Dartfish video analysis software to compare sexes. Poisson regression analyses were used to estimate HCs [direct (HC1) and indirect (HC2)], suspected concussion IRs, and IR ratios (IRRs). Game event, court location, and HC1 fouls were reported. Division 1 HC rates did not differ between boys (n = 238; IR = 0.50/10 player-minutes; 95% confidence interval [CI], 0.43-0.56) and girls (n = 220; IR = 0.46/10 player-minutes; 95% CI, 0.40-0.52). Division 2 boys experienced 252 HCs (IR = 0.53/10 player-minutes; 95% CI, 0.46-0.59); girls experienced 192 HCs (IR = 0.40/10 player-minutes; 95% CI, 0.35-0.46). Division 2 boys sustained higher HC1 IRs compared with Division 2 girls (IRR = 1.42; 95% CI, 1.15-1.74). Head contacts, rates did not differ between boys and girls in either Division. Suspected concussion IRs were not significantly different for boys and girls in each Division. Head contacts occurred mostly in the key for boys and girls in each Division. Despite illegality, HC1 penalization ranged from 3.9% to 19.7%. Head contact mechanisms varied across Divisions and sexes. Despite current safety measures, both HCs and suspected concussions occur in boys' and girls' basketball. Despite the illegality and potential danger associated with HC, only a small proportion of direct HCs were penalized and therefore targeting greater enforcement of these contacts may be a promising prevention target.

An Urgent Call for Concussion Incidence Measures in Para Sport for Athletes with Vision Impairment: A Narrative Review.

Concussion in para athletes with vision impairment (VI) is poorly understood. Recently published studies have suggested that athletes with VI may be more likely to sustain sport-related concussions compared to non-disabled athletes and athletes with other impairment types. There is a critical need for objective concussion incidence measures to determine concussion injury rates and risks more accurately. The aim of this review was to examine the limited available evidence of concussion incidence rates across six different para sports for athletes with VI and encourage the future collection of concussion incidence data and the adoption of injury prevention strategies in VI para sport. A literature search was conducted using four unique databases, which formed the basis of this narrative review. Injury prevention strategies such as modifying sport rules, introducing protective equipment, and incorporating additional safety measures into the field of play have been introduced sporadically, but the effectiveness of most strategies remains unknown. More prospective, sport-specific research examining mechanisms of injury and risk factors for concussion injuries in athletes with VI in both training and competition is needed. This research will help inform the development of targeted injury prevention strategies to reduce the likelihood of concussion for athletes with VI.

Incidence of concussion and associated risk factors in collegiate soccer: findings from the NCAA-DoD CARE consortium

ABSTRACT This retrospective cohort study aims to examine concussion incidence rates (IR) in collegiate soccer players and compare IRs based on risk factors including sex, competition level, games/practices, history of concussion, and playing position. Collegiate soccer players were recruited (n = 2,471) from 23 institutions from the NCAA-DoD Concussion Assessment, Research, and Education (CARE) Consortium. Incidence rates for concussion per 1000 athlete exposures (AEs) were calculated across the 2015–16/2016–17 seasons. Incidence rates (IR) comparing risk factor groups were also calculated. A total of 162 concussions occurred during the study, for an IR of 0.08/1000 AEs. Females were more likely to have a concussion than males overall (IR = 1.47) and were more likely to have a concussion in games (IR = 1.42) and practices (IR = 2.91). Concussions were more likely during competition compared to practice (IR = 2.53), and less likely in Division III, compared to Divisions I and II, χ2 = 6.5, p > .05. In the concussed group, male sex was associated with 2.47 times higher odds of playing defender and 2.29 times higher odds of a collision mechanism. Results confirm previous findings that females and game exposures have higher concussion IR than males and practice exposures. Findings also supported sex differences in IRs based on exposure type, position, and mechanism.

INCIDENCE AND CLINICAL MANIFESTATIONS OF CONCUSIONS IN ADOLESCENT AND PRE-ADOLESCENT ATHLETES PRACTICING OLYMPIC SPORTS

Background: Concussion is a frequent and sometimes severe complication of sport activity. The incidence in the USA is estimated at 538/100.000 person/year, while in Brazil there is no published estimate at that regard. The aim of our study was to evaluate the concussion incidence rate in adolescents and preadolescents athletes who practice different types of Olympic sports. Methods: This is a cross-sectional, retrospective study, which included volleyball, basketball, artistic gymnastics and judo adolescents (15-19 years old) and preadolescent (11-15 years old) athletes. An on line survey was sent to them by their coaches, and they were free to answer or not the questions. The central question was if they have had Traumatic Brain Injury/concussion in the last 12 months. If the answer was yes, then they had to respond to a questionnaire with several additional questions related to this concussion. Results: 66 athletes answered the survey; 23 out of 66 reported a concussion in the last 12 months. The overall incidence of concussion was 34.8%. The incidence per type of sport was 31,5% for volleyball, 20% for basketball, 57,1% for judo and 66,6% for artistic gymnastic. Those differences were not statistically significant, although there was a clear trend indicating the risk is higher for gymnastic and judo. There was no difference regarding the incidence according to gender or age distribution (adolescent versus preadolescents). The most frequent post-concussion symptoms were headache/migraine (73.9%), head pressure (26.1%), dizziness (13%), neck pain (13%) and changes in balance (13%). 12 out of the 23 (52.2%) athletes reporting a concussion had two or more symptoms (up to 8 symptoms). Conclusion: Our study showed that the incidence rate of sport concussions in our country is very high, at least in the universe of adolescent and preadolescent athletes. To our knowledge, this is the first report of concussion incidence in Brazil. It indicates that educational and medical measures should be employed as soon as possible, possibly under the lead of sport medicine specialists, in order to prevent or to deal with this complication in a standardized way.

Higher Rates of Head Contacts, Body Checking, and Suspected Injuries in Ringette Than Female Ice Hockey: Time to Ring in Opportunities for Prevention.

Ringette and female ice hockey are high participation sports in Canada. Despite policies disallowing body checking, both sports have high injury and concussion rates. This study aimed to compare physical contact (PC), head contact (HC), and suspected injury and concussion incidence rates (IRs) in female varsity ringette and ice hockey. Cross-sectional. Canadian ice arenas. Eighteen Canadian female university ringette and ice hockey tournament/playoff games in the 2018-2019/2019-2020 seasons. Game video-recordings were analyzed using Dartfish video-analysis software to compare both sports. Univariate Poisson regression analyses (adjusted for cluster by team, offset by game-minutes) were used to estimate PC, HC, and suspected injury IRs and incidence rate ratios (IRRs) to compare rates across sports. Proportions of body checks (level 4-5 trunk PC) and direct HC (HC 1 ) penalized were reported. Analyses of 36 team-games (n = 18 ringette, n = 18 hockey) revealed a 19% lower rate of PCs in ringette than ice hockey {IRR = 0.81 [95% confidence interval (CI), 0.73-0.90]}, but a 98% higher rate of body checking [IRR = 1.98 (95% CI, 1.27-3.09)] compared to ice hockey. Ringette had a 40% higher rate of all HC 1 s [IRR = 1.40 (95% CI, 1.00-1.96)] and a 3-fold higher rate of suspected injury [IRR = 3.11 (95% CI, 1.13-8.60)] than ice hockey. The proportion of penalized body checks and HC 1 s were low across sports. Body checking and HC 1 rates were significantly higher in ringette compared to ice hockey, despite rules disallowing both, and very few were penalized. These findings will inform future injury prevention research in ringette and female ice hockey.

Are Self-Reported and Parent-Reported Attention Problems and Hyperactivity Associated With Higher Rates of Concussion in Youth Ice Hockey Players?

To examine the association between self-reported and parent-reported attention problems and hyperactivity and rates of injury and concussion in Canadian youth ice hockey players. Secondary analyses of 2 prospective cohort studies. Canadian youth ice hockey teams. Ice hockey players (ages 11-17 years) were recruited by team, over 4 seasons (2011-2016). A combined 1709 players contributing 1996 player-seasons were analyzed (257 players participated in more than one season). Data were collected from preseason baseline questionnaires, including child and parent proxy forms of the Behavior Assessment System for Children, second edition. Injury and concussion rates and incidence rate ratios (IRR) comparing players with and without self-identified or parent-identified attention problems and hyperactivity, adjusted for covariates (ie, body checking policy, previous injury/concussion, and age) and a random effect for team, were estimated using multiple multilevel negative binomial regression. When analyzed continuously, rates of concussion increased with higher self-reported and parent-reported measures of attention problems [IRR SELF = 1.025; 95% confidence interval (CI): 1.011-1.040; IRR PARENT = 1.032; 95% CI: 1.008-1.057]. Self-reported hyperactivity was significantly associated with concussion (IRR = 1.021; 95% CI: 1.007-1.035), but parent-reported hyperactivity was not (IRR = 1.005; 95% CI: 0.983-1.028). A T score ≥ 60 cutoff combining attention problems and hyperactivity scores (an estimate of probable attention-deficit hyperactivity disorder) was not significantly associated with rates of injury or concussion. Attention problems and hyperactivity may place youth ice hockey players at increased risk of concussion and injury. Preseason assessments could identify players for targeted concussion education and risk reduction strategies.

Head Injury Assessment in the Elite Level Rugby Union in Japan: Review of 3 Seasons.

Head Injury Assessment (HIA) is the screening tool for head injury during a rugby game. The purpose of this study was to investigate the epidemiology of HIA in the Japan Rugby Top League (JRTL). The incidences of HIA, defined concussion (per 1,000 player-hours) and repeated concussions were evaluated in three seasons (2016-17, 2017-18, 2018-19; total 360 games). The HIA incidence rates were 12.7 (95% confidence interval 9.5-15.9), 20.8 (16.8-24.9), and 25.0 (20.5-29.5) in each season. HIA-1 criteria 2, which is applied for suspected concussion cases, was performed for 46 cases in the 2016-17 season, 81 cases in the 2017-18 season, and 88 cases in the 2018-19 season. The concussion incidence rates were significantly greater in the 2017-18 season (9.6/1000 player-hours, 95% confidence interval 6.8-12.4) and the 2018-19 season (14.4, 11-17.8) compared to the 2016-17 season (4.8, 2.8-6.8). The number of repeated concussion cases in the same season was 1 in the 2016-17 season and 4 in both the 2017-18 and 2018-19 seasons. This study confirmed significantly higher HIA and concussion incidence rates over time. Although the HIA system might have been established in the three seasons in JRTL, comprehensive management needs to be improved to prevent repeated concussions.

No association found between body checking experience and injury or concussion rates in adolescent ice hockey players

ObjectivesTo compare rates of injury and concussion among U-15 (ages 13–14 years) ice hockey players playing in leagues allowing body checking, but who have a varying number of years of...

Head Games: A Systematic Review and Meta-analysis Examining Concussion and Head Impact Incidence Rates, Modifiable Risk Factors, and Prevention Strategies in Youth Tackle Football.

The aims were to (1) examine the rates and mechanisms of concussion and head impact in youth football (high school level or younger); (2) identify modifiable risk factors for concussion and head impact; and (3) evaluate the effectiveness of prevention strategies in tackle football at any level. Nine databases (CINAHL Plus with Full Text; Cochrane Central Register of Controlled Trials; EMBASE; ERIC; Ovid MEDLINE(R) and Epub Ahead of Print, In-Process & Other Non-Indexed Citations and Daily; ProQuest Dissertations & Theses Global Database; PsycINFO; Scopus; and SPORTDiscus with Full Text) were searched using the search strategy focusing on four main concepts: concussion/head impact, tackle football, modifiable risk factors, and primary prevention. Two reviewers completed title, abstract, and full-text screening as well as risk of bias assessment (using the Downs and Black checklist), with a third author available to resolve any disagreements. After removing duplicates, 1911 articles were returned. Fifty-eight articles were included in the review and 20 in the meta-analysis. The overall combined rates of concussion (including game and practice-related concussion) based on the meta-analysis were 0.78 concussions/1000 athlete exposures [95% confidence interval (CI) 0.67-0.89] for high school football (ages 13-19) and 1.15 concussions/1000 athlete exposures (95% CI 0.89-1.41) for minor football players (ages 5-15). There is evidence that contact training and practice contact restrictions have reduced the rate of head impacts and concussion. Heads Up Football (an intervention focused on coach education and contact training) has been shown to reduce the rate of concussion by 32% and head impacts by 38% amongst high school football players. Limiting contact practices in high schools to 2days per week reduced practice head impacts per player-season by 42%, and limiting full contact in practice to 75min per week in the second week of the season and 60min in week 3 and beyond resulted in a 54% decrease in the practice-related concussion rate (p = 0.003). This review identified a critical need for interventions to address the high rates of concussion and head impact in youth football. To date, contact training and contact restrictions have the strongest evidence supporting their effectiveness at reducing these rates. Future research should use consistent concussion definitions and validated injury surveillance systems, and ensure complete reporting of participant characteristics and sampling details. Prospero ID CRD42020193775.

Does reducing the height of the tackle through law change in elite men’s rugby union (The Championship, England) reduce the incidence of concussion? A controlled study in 126 games

ObjectivesMost concussions in rugby union occur during tackles. We investigated whether legislation to lower maximum tackle height would change tackle behaviour, and reduce concussion incidence rate.MethodsIn an observational evaluation using...

Content analysis of concussion education for coaches of youth and high school sport

ABSTRACT Objective Describe the extent to which concussion education provided to coaches of US high school and youth sport is inclusive of information necessary for them to engage in target behaviors related to the prevention, identification and management of concussion. Methods Sport organizations included in the sample were US state high school governing bodies and national governing bodies (NGBs) for youth sports with the highest concussion incidence rates. The concussion education resources made available online for coaches by these organizations were coded for content relevant to concussion prevention, identification and management. Results All but one state high school governing body required coach concussion education, two NGBs required coach education, seven recommended it and only one did not require or recommend it. All educational materials covered at least 84% (n = 16/19) of the relevant knowledge domains. Discussion Existing concussion education for coaches is addressing most, but not all, topics that may help coaches engage in concussion prevention, identification and management. Additional program development work is warranted to augment educational content related to coach communication about concussion safety with athletes and parents. Content appropriateness notwithstanding, further research is needed to understand the acceptability, efficacy, and implementation of concussion education for coaches.

Concussion Burden, Recovery, and Risk Factors in Elite Youth Ice Hockey Players.

To examine rates of concussion and more severe concussion (time loss of greater than 10 days) in elite 13- to 17-year-old ice hockey players. This is a prospective cohort study (Alberta, Canada). Bantam (13-14 years) and Midget (15-17 years) male and female elite (top 20% by division of play) youth ice hockey players participated in this study. Players completed a demographic and medical history questionnaire and clinical test battery at the beginning of the season. A previously validated injury surveillance system was used to document exposure hours and injury during one season of play (8 months). Players with a suspected ice hockey-related concussion were referred to the study sport medicine physicians for assessment. Time loss from hockey participation was documented on an injury report form. Overall, 778 elite youth ice hockey players (659 males and 119 females; aged 13-17 years) participated in this study. In total, 143 concussions were reported. The concussion incidence rate (IR) was 17.60 concussions/100 players (95% CI, 15.09-20.44). The concussion IR was 1.31 concussions/1000 player-hours (95% CI, 1.09-1.57). Time loss of greater than 10 days was reported in 74% of cases (106/143), and 20% (n = 28) had time loss of greater than 30 days. Concussion is a common injury in elite youth ice hockey players. In this study population, a large proportion of concussions (74%) resulted in a time loss of greater than 10 days, possibly reflecting more conservative management or longer recovery in youth athletes.

Incidence reporting via online high school concussion surveillance by certified athletic trainers and school nurses, 2015\u20132018

BackgroundThere is an increasing concern over adolescent concussions in sports due to risks of long-term negative effects. This study analyzed data over three school years on reported concussion incidence rates by season, high school grade levels and gender, and reported symptoms by school nurses versus athletic trainers, from New Jersey student-athlete concussion data available from an online school-based surveillance system.MethodsSchool nurses and athletic trainers reported 300 concussions within five days from when each occurred over three school years, 2015–2018, in team sports and physical education in New Jersey high schools. Analysis was further conducted on symptoms and number of symptoms reported by school nurses versus school athletic trainers for each documented student-athlete concussion. Estimated concussion incidence rates were calculated using state agency verified school enrollment data.FindingsConcussions most commonly occurred during fall, followed by spring, then winter. Concussion incidence rates ranged from 6.3/1000 (4.99, 7.55) – 9.1/1000 (7.27, 10.98) students over the three school years of the study. Athletic trainers completed 86% of the reports while nurses completed 11% (position or title of 3%, or n = 7, were not disclosed); the values were similar when considering only fall pre-season and regular season sports (88, 10, 2%, respectively). On average, across the three school years, athletic trainers reported about 3.5 symptoms per report while nurses reported 2.7 (values in fall seasons only were 3.7 and 3.1, respectively.)ConclusionsCertified athletic trainers, compared to school nurses, more often completed concussion report forms and reported more symptoms per injured student, perhaps due partly to closer contact and immediate care provided after injury. Additionally, this study had a higher concussion incidence rate during fall sports seasons compared to winter and spring. Future research can further improve our understanding of concussions among adolescent student-athletes to better inform concussion identification, management and recovery protocols.

The Epidemiology of Sport-Related Concussion: What the Rehabilitation Clinician Needs to Know.

Sport-related concussion is common in full-contact and collision sports. Epidemiology studies use different types of surveillance systems and concussion definitions. Concussion incidence rates vary across age, sex, sport, and level of competition. Incidence rates are increasing, likely due to higher rates of reporting following improved knowledge and increased regulations. In this review, we summarize 7 key concepts related to concussion epidemiology: concussion definition, changes in concussion knowledge, reliability and accuracy of injury surveillance systems, conservative management and return to play, reliability of self-report, incidence of concussion across levels of play, and understanding the behaviors of players, coaches, and medical personnel from a multidisciplinary management perspective. J Orthop Sports Phys Ther 2019;49(11):768-778. doi:10.2519/jospt.2019.9105.

Sex-Based Differences in the Incidence of Sports-Related Concussion: Systematic Review and Meta-analysis.

The incidence of sports-related concussion in females has been increasing in recent years. To conduct a meta-analysis on sex-based differences in concussion incidence in various sports and to determine the effects of study design (retrospective vs prospective), setting (competition vs practice), and population (university and above vs high school and below) via a meta-regression. PubMed (Medline), EMBASE, and Cochrane Library databases were searched from January 2000 to January 2018. Studies reporting sports-related concussion incidence data for both males and females (age ≥10 years) were included. Systematic review with meta-analysis and meta-regression. Level 4. The rate ratio was calculated as the concussion rate in females/males. Data were pooled using the DerSimonian-Laird random-effects model. Thirty-eight studies met the eligibility criteria and were included in the meta-analysis. Soccer and basketball demonstrated significantly higher incidence of concussions in females compared with males (rate ratio [95% CI], 1.76 [1.43-2.16] and 1.99 [1.56-2.54], respectively; P < 0.01). Sex-based differences in concussion incidence rates for baseball/softball, ice hockey, lacrosse, swimming/diving, and track and field were not statistically significant. In the meta-regression analysis, there were no significant effects on the rate ratio when evaluating study design, setting, and population. Concussion incidence rates were significantly higher in females than in males for soccer and basketball.

Trends in United States High School Soccer Concussion Reporting from 2012–2017

Abstract Purpose The purpose of this study was to provide updated high school soccer concussion incidence rates by gender and event type. It was hypothesized more soccer injuries occur in females, during games, and that females would have higher injury rates and risk. Methods This study used data from the Rank One Health Injury Surveillance Database (ROH ISD) between 2012–17, from 1,999 high schools in student-athletes ages 14 to 18. This study examined high school soccer concussion incidence rate reporting by Athletic Trainers (ATCs). Injury rates per 1,000 Athletic Exposures, injury rate ratios (IRRs), and risk ratios (RR) were calculated by event type. All 95% confidence intervals (CIs) not containing 1.0 were considered statistically significant. Results A total of 6,669 concussions with an average age of 15.62 (SD=1.26) were reported by ATCs in high school soccer from 2012-17. More concussions occurred in games (4,527; 67.9%) than practices (2,142; 32.1%). During games, males (3.49/1,000 AEs) had lower rates than females (7.78/1,000 AEs). During practice, males (0.52/1,000 AEs) had lower rates than females (0/97/1,000 AEs). Injury risk ratio was higher in games than practices for males (RR=6.71; 95% CI=6.67, 6.75) and females (RR=8.11; 95% CI=8.08, 8.14). Conclusion This study marks the largest epidemiological high school soccer concussion incidence investigation to date. The findings from this study provide updated high school soccer concussion incidence rates and provide further evidence of differences in injury rates when comparing practices and games.

Trends in US High School Football Concussion Reporting, 2012-2017

Objectives: Football has been a sport with high concussion rates when examined independently (Rosenthal et al., 2014). Accurately describing injury trends in high school sports is necessary to identify student-athletes at the greatest risk of injury and where potential injury reduction interventions should be focused. With increased reported high school concussion injuries and associated state legislative requirements, increased incidence rates are needed. The purpose of this study was to provide updated high-school football concussion incidence rates. Methods: Data Source and Study Period This study used data from the Rank One Health Injury Surveillance Database (ROH ISD). Data for the current study were analyzed across 6 calendar years (2012 through 2017) from 1,999 high schools. Data from the current study examined high school football concussion data in males ages 14 to 18. The ROH ISD consists of a convenience sample of participating schools from 2012 to 2017. Exposure and injury data represent a convenience sample of US high schools. For the current study, only data provided across all 1,999 high schools were included. All 1,999 high schools included in the current study logged practice and game participation events for each individual athlete participating in football at the respective high school and athletic exposures (AEs) are an accurate representation of rostered athletes participating in either practices or games by age and calendar year. The ROH ISD was deemed Category 4 IRB exempt. Statistical Analysis Injury counts, practice exposures, game exposures, and distributions by event type (practice or game), age, and injury mechanism were examined. Injury rates per 1,000 AEs and injury rate ratios (IRRs) were calculated by event type. Injury proportion ratios (IPRs) were used to examine differences by calendar year. Risk ratios (RRs) were calculated to compare event type by calendar year. All 95% confidence intervals (CIs) not containing 1.0 were considered statistically significant. Results: 997,308 male student-athletes participated in high school football. ATs recorded a total of 14,103 concussions in high school football from a total of 235,134 total injuries across all high school sports. High school football concussions accounted for 6% of all injuries in high school sports from 2012-2017. More concussions occurred in games (51.8%) than practices (48.2%). Decreases were found in annual injury rates for practices in high school football student-athletes from 2012 to 2016 with an increase in 2017. Decreases were found in annual injury rates for games from 2012 to 2016 with an increase in 2017. IPR decreased by year from 2012 to 2016 (with an increase in 2017. IRR and RR comparisons for games versus practices were significant from 2012 to 2017 (Table 1). Conclusion: This study marks the largest epidemiological high school football concussion incidence investigation to date. The findings from this study provide updated high school football concussion incidence rates and provide further evidence of differences in injury rates when comparing practices and games. The higher rates of concussions occurring in games relative to practices emphasize prior trends of injury risk relative to the level of competition. Overall, results highlight a decline in injury rates over time and lower rates of injury compared to prior high school football epidemiological concussion studies. [Table: see text]

Effect of Playing and Training at Altitude on Concussion Incidence in Professional Football.

Background:Despite the increased attention to sports-related concussion, the literature lacks information about the environmental factors that contribute to concussion incidence. Previous investigators have noted a decreased rate of concussion in football games played at higher altitude.Purpose/Hypothesis:The purpose of this study was to investigate whether the protective effects of altitude on concussion rate, as described by previous investigators, were due to acute effects of altitude exposure or chronic adaptations to training at altitude. Our hypothesis was that these protective effects are not attributable to relative cerebral edema that occurs in conditions of altitude-associated hypobaric hypoxia, known as the “slosh effect,” but rather result from long-term adaptations to training at altitude.Study Design:Descriptive epidemiology study.Methods:Athletes from the 2012, 2013, 2014, and 2015 National Football League (NFL) seasons were included in this analysis of publicly available data. Concussion rates were subdivided into 4 groups: (1) low-altitude teams playing below 644 feet (low-low), (2) low-altitude teams playing above 644 feet (low-high), (3) high-altitude teams playing below 644 feet (high-low), and (4) high-altitude teams playing above 644 feet (high-high).Results:Away teams had a significantly higher rate of concussion (0.32 concussions per exposure) compared with their home team counterparts (0.27 concussions per exposure; P = .03). Teams training and playing at high altitude had a 28% decreased concussion rate, which was significantly lower compared with concussion incidence rates for overall, low-low, and high-low groups (P < .05). In comparison, teams that trained at altitude but played below 644 feet had the highest rate of concussion, at 0.36 concussions per exposure (P < .05).Conclusion:These data indicate that living and training at altitude may have a protective effect on concussion rate, as evidenced by the significant reduction in the high-high group and the lack of an effect in the low-high group. However, teams from low altitude playing at high altitude did not have a statistically significant reduction in concussion rate. These results show that the slosh theory does not completely explain the effects of altitude on concussion incidence rate in the NFL. Further analyses are needed to investigate the true cause of altitude-induced protection in the NFL.