Concussion Rates Research Articles

Concussion Characteristics in the National Hockey League Before and After the Introduction of Rule 48

A rule prohibiting a direct hit to the lateral side of the head (ie, Rule 48-Illegal Check to the Head) was introduced in the National Hockey League (NHL) in the 2010-2011 season and refined in the 2011-2012 season to widen the application to include direct contact to all areas of the head. To compare the incidence and proportion of concussions that occurred following hits to the head before and after the implementation of Rule 48. This retrospective cohort study used a before and after design to evaluate concussions among NHL players in regular season games. Data from the 4 seasons preceding the implementation of Rule 48 (2006-2007 to 2009-2010) were compared with data from 5 seasons following its implementation (2014-2015 to 2018-2019). Data were analyzed from October 31, 2021, to November 30, 2022. The incidence and relative proportion of concussion characteristics and mechanisms before and after the introduction of Rule 48. In the analysis of 688 concussions for NHL seasons spanning 2006 to 2010 (n = 231) and 2014 to 2019 (n = 457), there was an overall increase in the incidence of concussion between the 2 time frames, although the incidence of concussions due to hits to the lateral aspect of the head decreased from 1.6/100 games to 1.0/100 games (estimated difference, 0.6/100 games [90% credible interval (CrI), 0.30/100 games to 0.90/100 games). There was also a reduction of 18.8 (90% CrI, 13.0-23.7) percentage points in the proportion of concussions due to hits to the lateral aspect of the head from 80 of 231 concussions (34.6%) to 61 of 457 concussions (13.3%). The incidence of concussions following hits to the head from body checks using the shoulder, arm, and glove was similar before and following the implementation of Rule 48. However, the proportion was reduced 14.7 percentage points from 113 of 231 concussions (48.9%) before to 149 of 457 concussions (32.6%) after implementation of Rule 48 (90% CrI of the difference, 8.9-20.7 percentage points). The findings of this cohort study of NHL players suggest that after the introduction of Rule 48, the incidence rate and proportion of concussions from contact to the lateral aspect of the head decreased, as did the proportion of concussions following direct hits to the head.

Differences in injury and concussion rates in a cohort of Canadian female and male youth Rugby Union: a step towards targeted prevention strategies

ObjectiveTo examine differences in match and training musculoskeletal injury and concussion rates and describe mechanisms of concussion while considering previous playing experience in female and male Canadian high school Rugby...

Risk Factors for Concussion in Under 18, Under 22 and Professional Men's Rugby Union: A Video Analysis of 14,809 Tackles

ObjectiveThis study aimed to identify the risk factors for tackle-related concussion observed in matches involving under (U) 18, U 22 and professional men’s Rugby Union players through video analysis.Study DesignDescriptive epidemiology study.MethodsTwenty Rugby Union matches each for high school (U18), university/college (U22) and professional (Elite) were randomly selected from 202 matches in the 2018/2019 season. Both one-on-one and tackles involving multiple tacklers were analyzed for the 60 matches. The 28 categorical and continuous variables (e.g., tackle characteristics and duration before the tackle) were applied as risk factors to a least absolute shrinkage and selection operator (Lasso) regression analysis. To identify high-risk situations, a simulation model with coefficients obtained from the Lasso regression was used. Statistical analysis was conducted according to tackle direction.ResultsA total of 14,809 tackles and 41 concussions involving 1800 players were included in the analyses. The incidence rate of concussions (injuries/1000 tackles) was greater in Elite players (4.0) compared with U18 (1.9) and U22 (2.4) players. The factors most highly associated with concussions were head-in-front tackles (where the tackler’s head is placed forward, impeding a ball carrier’s forward movements, 11.26/1000 tackles), and were more often observed among U18 players. A simulation model predicted that the highest risk tackle situation in Elite players was a head-in-front, side-on tackle below the hip of the ball carrier (predicted incidence rate 18.07/1000 tackles).ConclusionThe risk factors associated with concussion need to be assessed cautiously. Avoiding head-in-front, side-on tackles to the lower extremities of a ball carrier should be considered to reduce injury risks.

Incidence of Concussions in Elite Female Water Polo: A Retrospective Analysis.

Current evidence for concussions is mixed in water polo players. Surveys suggest rates as high as 36%, whereas surveillance studies at international competitions often fail to report them at all. The goal of this study was to examine the incidence of concussions in elite female water polo players from surveillance tools implemented longitudinally. Retrospective chart analysis of 10 years spanning between 2012 and 2022. National teams or professional sports. Female players from the Canadian senior national water polo teams that participated in international competitions and trained more than 10 hours per week in a competitive environment. Included player position, recurrence, and time loss before full return to play. Prevalence of concussion diagnosis. Forty-three concussions were identified over the 10 years observed at a median count of 3 concussions per year. Cumulative days lost spanned between 25 and 348 days per team*year. Altogether, this produced a median rate of 14.3 injuries per 100 player*years. Goalkeepers in the sample suffered the highest rates of concussion (25.8%), compared with players in other positions (22.8% of centers and 16.7% of drivers). This study found evidence for prevalence of concussions in elite female water polo players. Improved guidelines preceded a significant reduction in time loss after the year 2017. This adds to a body of knowledge suggesting that improved surveillance methods are needed to detect and care for concussions in this population.

Are Sex Differences in Collegiate and High School Sports-Related Concussion Reflected in the Guidelines? A Scoping Review.

Background: Sport-related concussion (SRC) is a common sport injury. Females are participating in sports at increasing rates, and there is growing awareness that female athletes may be more vulnerable to SRC. Objectives: We aimed to identify sex differences in epidemiology, clinical manifestation and assessment of SRC and examine how these relate to the 6th International Conference on Concussion in Sport (ICCS). Methods: We conducted a scoping review of the Medline database and identified 58 studies examining the effects of sex on SRC in collegiate and high school athletes that were written in English and published in a peer-reviewed journal between March 2012 and March 2022. Results: We found that female athletes suffer higher rates of concussion in sex-comparable sports, in particular soccer. Female athletes experience more somatic symptoms-headache/migraine/sleep disturbance-and may take longer to recover from concussion. Sex differences were also identified regarding some aspects of sideline concussion assessment with the Sport Concussion Assessment Tool. Conclusions: Females are at greater risk and experience SRC differently than males; this is mostly likely due to a combination of biomechanical factors, differences in neck musculature and hormonal and social factors. Sex differences are not widely addressed by the 6th ICSS, which informs many sports' concussion protocols.

Clustering Of Sport-Related Concussion Rates By Season Segment In National Collegiate Athletic Association Sports: Findings From The NCAA Injury Surveillance Program Between 2013/14-2018/19

Clustering Of Sport-Related Concussion Rates By Season Segment In National Collegiate Athletic Association Sports: Findings From The NCAA Injury Surveillance Program Between 2013/14-2018/19

Is All Publicity Good Publicity? A Sentiment Analysis of Media Regarding Concussions in the NFL and its Effects on Viewership

With the increase in the rate of concussions within the National Football League (NFL), as well as an increase in studies finding the long-term effects of these concussions, there has been growing interest garnered by the media on the NFL’s concussion protocol. Other studies would suggest that these portrayals by the media, if negative, would impact the league's viewership; however, with no research done on the topic, this claim was unsupported. To determine this relationship, this study conducts a sentiment analysis using MeaningCloud Software on statements made within the years 2017 through 2021 regarding NFL concussions/concussion protocol, which was then compared to the average viewership of its corresponding season. Throughout the entirety of the years analyzed, MeaningCloud analyzed that 49 of the 99 statements about NFL concussions/concussion protocol were deemed to have negative polarity (49.5%), while only 24 had positive polarity (24.24%), conveying a very large disparity in the media coverage. These results disagreed with the current ideals that negative portrayals can impact enjoyment (therefore viewership), and could speak to the strength of the NFL’s business model.

Estimating the Relationship Between the Symptom-Free Waiting Period and Injury Rates After Return-to-Play from Concussion: A Simulation Analysis Using CARE Consortium Data.

A key component of return-to-play (RTP) from sport-related concussion is the symptom-free waiting period (SFWP), i.e., the period during which athletes must remain symptom-free before permitting RTP. Yet, the exact relationship between SFWP and post-RTP injury rates is unclear. We design computational simulations to estimate the relationship between the SFWP and rates of repeat concussion and non-concussion time-loss injury up to 30 days post-RTP for male and female collegiate athletes across 13 sports. We leverage N = 735 female and N = 1,094 male post-injury trajectories from the National Collegiate Athletic Association-Department of Defense Concussion Assessment, Research, and Education Consortium. With a 6-day SFWP, the mean [95% CI] rate of repeat concussion per 1,000 simulations was greatest in ice hockey for females (20.31, [20.16, 20.46]) and American football for males (24.16, [24.05, 24.28]). Non-concussion time-loss injury rates were greatest in field hockey for females (153.66, [152.59, 154.74]) and wrestling for males (247.34, [246.20, 248.48]). Increasing to a 13-day SFWP, ice hockey for females (18.88, [18.79, 18.98]) and American football for males (23.16, [23.09, 24.22]) exhibit the greatest decrease in repeat concussion rates across all sports within their respective sexes. Field hockey for females (143.24, [142.53, 143.94]) and wrestling for males (237.73, [236.67, 237.90]) exhibit the greatest decrease in non-concussion time-loss injury rates. Males receive marginally smaller reductions in injury rates for increased SFWP compared to females (OR=1.003, p ≤0.002). Longer SFWPs lead to greater reductions in post-RTP injury rates for athletes in higher risk sports. Moreover, SFWPs should be tailored to sport-specific post-RTP injury risks.

Effect of the 2018 NCAA Kickoff Rule Change on Concussion Rates in Collegiate Football: Results From a Division 1 Conference.

Kickoff plays in American football are associated with an increased risk of concussion compared with other play types. In 2018, the National Collegiate Athletic Association (NCAA) Football Rules Committee altered the kickoff rules so a fair catch inside the 25-yard line results in a touchback, with the ensuing drive starting on the 25-yard line. The intention was to decrease the number of kickoff returns with a corresponding decrease in the rate of concussions on kickoff plays. To determine whether the 2018 rule changes had the intended effects in an NCAA Division 1 Conference. Cohort study; Level of evidence, 3. The study population included football athletes in the NCAA Pacific-12 (Pac-12) Conference. Data on the total number of plays, punts, kickoffs, touchbacks, and fair catches were obtained for all in-conference games from the 2016 to 2021 seasons. The number of game concussions and the play type were provided by each conference institution. Incidence of concussions occurring during kickoff plays before (2016-2017) and after (2018-2021) the rule change were compared with a difference-in-difference analysis using Poisson general linear models. There were 242 concussions in 108,774 total plays in the study period, with an overall concussion rate of 2.2 per 1000 plays. The percentage of touchbacks increased significantly from 45% to 51% (P < .001) and the percentage of fair catches increased from 1% to 7% (P < .001) from before to after the rule change. Kickoffs accounted for 6% of plays both before and after the rule change and 11% of concussions before and 14% after the change. The mean annual concussion rate (per 1000 plays) on kickoffs was 3.42 before and 5.31 after the rule change (rate difference: 1.89; 95% confidence interval, -1.22 to 5.01). Touchbacks and fair catches increased after the kickoff rule change, but there was not a corresponding decrease in concussions during kickoff plays as anticipated. Concussions occurring during other football plays remained stable.

Head Impact Exposure in Female Collegiate Soccer by Activity Type

Soccer, one of the most popular sports in the world, has one of the highest rates of sports-related concussions. Additionally, soccer players are frequently exposed to nonconcussive impacts from intentionally heading the ball, a fundamental component of the sport. There have been many studies on head impact exposure in soccer, but few focus on soccer practices or practice activities. This study aimed to characterize the frequency and magnitude of head impacts in National Collegiate Athletic Association Division I female soccer practice activities using a custom-fit instrumented mouthpiece. Sixteen players were instrumented over the course of 54 practice sessions. Video analysis was performed to verify all mouthpiece-recorded events and classify practice activities. Category groupings of practice activities include technical training, team interaction, set pieces, position-specific, and other. Differences in head impact rates and peak resultant kinematics were observed across activity types and category groupings. Technical training had the highest impact rate compared to other category groupings. Impacts occurring during set piece activities had the highest mean kinematic values. Understanding drill exposure can help inform coaches on training plans aimed to reduce head impact exposure for their athletes.

Injuries and Overuse Syndromes in Rink Hockey Players.

Rink Hockey is a high-speed low-contact sport with a widely recognized injury potential. Played with a hard ball by players wearing little or no protective gear, the rates of concussions and head injuries are of high interest. In this study, we reviewed and investigated injuries sustained by 108 German National League rink hockey players. We conducted an epidemiological cross-sectional study to determine sport-specific injuries and injury patterns in female and male rink hockey players. Data were collected by a standardized questionnaire. A total of 108 players participated in the study. The combined rate of injuries were 9.4/1000 athlete exposures. There was no significant difference between injury rates during games and practice. A sexspecific difference was not detected. Head injuries were the most frequent type (20.8 % of all injuries). Concussions made up 7 % of all head injuries with a rate of 0.76/1000 athlete exposure. Ball contact was the cause for 31 % of injuries, while player contact generated 26.2 % of all injuries. High rates of ball-contact-related injuries resulted in time loss and medical consultations. Head injuries were frequent, however did not result in significant time loss as compared to other injuries. The use of protective gear should be recommended.

Factors Associated With Concussion Rates in Youth Ice Hockey Players: Data From the Largest Longitudinal Cohort Study in Canadian Youth Ice Hockey.

To examine factors associated with rates of game and practice-related concussion in youth ice hockey. Five-year prospective cohort (Safe2Play). Community arenas (2013-2018). Four thousand eighteen male and 405 female ice hockey players (6584 player-seasons) participating in Under-13 (ages 11-12), Under-15 (ages 13-14), and Under-18 (ages 15-17) age groups. Bodychecking policy, age group, year of play, level of play, previous injury in the previous year, lifetime concussion history, sex, player weight, and playing position. All game-related concussions were identified using validated injury surveillance methodology. Players with a suspected concussion were referred to a study sport medicine physician for diagnosis and management. Multilevel Poisson regression analysis including multiple imputation of missing covariates estimated incidence rate ratios (IRRs). A total of 554 game and 63 practice-related concussions were sustained over the 5 years. Female players (IRR Female/Male = 1.79; 95% CI: 1.26-2.53), playing in lower levels of play (IRR = 1.40; 95% CI: 1.10-1.77), and those with a previous injury (IRR = 1.46; 95% CI: 1.13, 1.88) or lifetime concussion history (IRR = 1.64; 95% CI: 1.34-2.00) had higher rates of game-related concussion. Policy disallowing bodychecking in games (IRR = 0.54; 95% CI: 0.40-0.72) and being a goaltender (IRR Goaltenders/Forwards = 0.57; 95% CI: 0.38-0.87) were protective against game-related concussion. Female sex was also associated with a higher practice-related concussion rate (IRR Female/Male = 2.63; 95% CI: 1.24-5.59). In the largest Canadian youth ice hockey longitudinal cohort to date, female players (despite policy disallowing bodychecking), players participating in lower levels of play, and those with an injury or concussion history had higher rates of concussion. Goalies and players in leagues that disallowed bodychecking had lower rates. Policy prohibiting bodychecking remains an effective concussion prevention strategy in youth ice hockey.

Poster 380: Decreased concussion incidence following revised contact rules; An updated epidemiology of NFL concussions from 2017-2022

Objectives: The incidence of concussions in football, and the media attention that followed, has garnered scientific investigation, prompted technological advances in protective gear, and altered the rules of the game, including the NFL’s “Targeting” rule, which began in 2018. In previously studied seasons, certain positions, such as offensive skill players, had higher rates of concussions while defensive secondary and offensive line players suffered the greatest number of concussions, but the severity of these concussions has not been reported. The advent of the “Targeting” rule has been shown to reduce concussions in collegiate football leagues, but its effect on NFL and professional-level players is unknown. The objectives of this retrospective study were to describe the epidemiology of concussions among professional football players in the NFL during the last five seasons, determine changes in incidence over the study period, and characterize positional differences in rate and games missed. Methods: The current study was a descriptive epidemiological study that retrospectively reviewed all concussions that occurred in the five NFL seasons from the 2017-2018 season through the 2021-2022 season that resulted in at least one game missed. Total concussions, total games missed due to concussion, and average games missed per concussion were extracted from publicly available injury reports and were cross-referenced with publicly available sources. Concussion rates were calculated per 1,000 athletic exposures (AEs). A sub-analysis was performed by year, game unit, position type, and game week. Results: In 1,216 regular season games in the five NFL seasons, there were a total of 368 concussions for a rate of 0.30 concussions per game and 7.04 concussions per 1,000 AEs. More concussions were concentrated in the last one-third of the regular season. There was a statically significant decrease (38%; p&lt;0.05) in total concussions between the 2017-2018 season (102 total concussions) and the four seasons between 2018-2019 and 2021-2022 (average of 73.8 concussions per year). During the five seasons, there were 1,014 games missed due to concussion, an average of 2.76 games missed per concussion, and 0.056 games missed due to concussion per 1,000 AEs. Following the 2017-2018 season, there was a 53% decrease in the total games missed due to concussion (Figure 1b) and a 38% decrease in the average games missed per concussion (Figure 1c). Descriptively, both offensive and defensive units had decreased concussion rates and average games missed per concussion in the four seasons after 2017 (Figure 2). Defensive backs (10.46 per 1,000 AEs) and tight ends (10.69 per 1,000 AEs) had the highest concussion rates. The defensive line had the highest average games missed per concussion at 3.97 (Table 1). Conclusions: The introduction of the “Targeting” rule in the NFL beginning in the 2018 season correlated with a decrease in total concussions per year, total games missed per concussion, and games missed per concussion. Both offensive and defensive units experienced similar reductions in concussion incidence and severity. Overall, the updated epidemiology of NFL concussions suggests that efforts to protect professional football players from concussions have been successful, however, players continue to experience concussions that require them to miss multiple games. [Table: see text]

Paper 60: Effect of Mouthguard Type on Severity of Concussion During Game-Related College Football Competition. A 16-Season Prospective Study

Objectives: Prior studies have either claimed or disputed the role of mouthguard protection in reducing the incidence of concussion. Other than investigating a decrease in concussion rate, no long term studies have specifically compared the effect of type of mouthguard protection on the severity of concussion. The increasing incidence of head trauma in sport, the potential for long-term traumatic brain injury, and concerns of rising medical costs, dictate a focus on variables that may influence concussion severity in contact sports. Therefore, this study quantified the effect of mouthguard type on severity of concussion during game-related college football competition. Methods: 40 universities were evaluated over 16 competitive seasons (2006-2021) across all Football Bowl Subdivision (FBS) conferences. Mouthguard type was divided into two groups based on dentist- fitted and self-fitted (generic/boil and bite). Outcomes of interest included concussion severity (simple: 0-10 days time loss, complex: &gt; 10 days time loss), injury category, player position, injury situation, injury mechanism, elective imaging, and playing surface. Data were subject to multivariate analyses of variance (MANOVA) and Wilks’ λ criteria using GLM procedures, and expressed as incidence rates (lR) per 10 game season. Results: Of the 2,332 games documented, 9,563 total injuries were reported, resulting in 708 (589 simple, 119 complex) concussion cases, consisting of 653 player-to-player contacts and 55 player-to- surface impacts. MANOVA indicated significant main effects of mouthguard type by concussion severity ( F1,705 = 3.587; P = .028), player position by team ( F2,705 = 3.551; P = .029), player position by skill position ( F8,699 = 2.373; P = .016), and injury mechanism ( F6,701 = 4.467; P &lt; .001). Post hoc analyses indicated a significantly lower ( P = .023) incidence of complex concussions [1.3, (95% CI, 0.9-1.6) vs 2.1 (1.7-2.5)], with a significantly higher ( P = 0.014) occurrence of simple concussions [8.7, (95% CI, 8.4-9.1) vs 7.9 (7.5- 8.3)] while wearing dentist-fitted versus self-fitted mouthguards, respectively. Although significantly greater ( P &lt;.05) incidences of concussion were documented across offensive teams [4.3, (95% CI, 3.8- 4.8) vs 3.3 (2.9-3.8)], quarterbacks [0.9, (95% CI, 0.6-1.2) vs 0.3 (0.2-0.6)], and players tackled above the waist [2.8, (95% CI, 2.4-3.3) vs 1.7 (1.4-2.1)] than observed across other teams and injury mechanisms while wearing dentist-fitted as compared to self-fitted mouthguards, respectively. The majority of these cases, however, were diagnosed as simple concussions. Of the 1,150 games (49.3%) played on a 3-layer artificial turf (≥9.0 lbs/ft2) infill system and 1,182 games (50.7%) played on natural grass, surface-related concussions on artificial turf (n = 26; 3.7% of total concussions; 21 simple, 5 complex concussions) and natural grass (n = 30; 4.2 % of total concussions; 23 simple, 7 complex concussions) were minimal and less severe on both surfaces than often perceived. Conclusions: The significantly lower incidence of complex concussions documented with dentist-fitted mouthguards during college football competition may reflect greater shock absorption and redistribution of energy during head impact due to more optimal fit and fabrication when compared to self-fitted mouth protection, translating to less severity of trauma and more expedient return to play. This longitudinal study directly compares and addresses type of mouthguards as they relate specifically to concussion severity. Although findings of this study may be generalizable only to this level of football competition, further research is warranted into lower levels of competition, e.g., high school, youth football, where the use of self-fitted mouthguards is prevalent.

A-39 A Comparison of Concussion Reporting between the Olympic and Paralympic Games

Abstract Purpose Research has established that the Paralympic Games have a higher injury rate than the Olympic Games, but less is known about how concussion rates may differ between these two populations. Concussions in Paralympic athletes are more difficult to accurately diagnose due to the lack of robust concussion guidelines specific to para athletes. This literature review sought to compare reporting of concussion symptoms and incidence between the Paralympic and Olympic Games since 2010. Data Selection: Searches of Google Scholar, PubMed, and ResearchGate were performed to identify Paralympic and Olympic injury and surveillance study data. Hand-searching citation lists yielded additional results. Articles were included if they reported head injury and/or concussion data. Results Fourteen articles were included that provided injury surveillance study data from 2010 to 2022. Data on head injury and concussion incidence and diagnosis were extracted and reviewed. Between 2010 and 2018, higher concussion rates were reported in Olympic athletes, possibly due to the lack of concussion-specific injury questions for Paralympic athletes. When concussion-specific injury questions for Paralympic athletes were implemented in 2018, data suggests that Paralympic athletes sustained more concussions than Olympic athletes. Additionally, the review suggested potential under-reporting of concussions in Paralympic athletes, despite symptoms, suggesting incidence may be higher than reported. Conclusions Higher concussion rates in the Paralympic Games and possible under-reporting of concussions highlights the need for improved identification and evaluation of concussions in Paralympic athletes. Establishing robust guidelines for the identification, evaluation, and management of concussions for para athletes is critical to increase their safety.

Prevention strategies and modifiable risk factors for sport-related concussions and head impacts: a systematic review and meta-analysis

ObjectivesTo evaluate prevention strategies, their unintended consequences and modifiable risk factors for sport-related concussion (SRC) and/or head impact risk.DesignThis systematic review and meta-analysis was registered on PROSPERO (CRD42019152982) and conducted...

Sports Participation and Sports-Related Neurologic Injuries in Pediatric Patients With Arachnoid Cysts.

Currently, there is no consensus recommendation regarding the safety of sports participation for pediatric patients with arachnoid cysts (ACs). To prospectively survey patients with ACs to define the risk of sports-associated neurologic injury in untreated and treated patients. A prospectively administered survey was given to all patients diagnosed with an AC who presented to a single pediatric neurosurgery clinic between December 2010 and December 2021. Data were recorded on demographic information, imaging characteristics, treatment, sports participation, and presence of sports-related neurologic injury. The type and date of surgery for the AC were noted if surgery was performed. Of the 303 patients with completed surveys, 189 patients participated in sports, and 94 patients had prospective data available. There was no significant difference in cyst location or Galassi score between patients who did and did not participate in contact vs noncontact sports and those who did and did not experience a concussion. A cumulative total of 2700.5 seasons of sports were played (2499.7 in untreated and 200.8 in treated patients). There were 44 sports-related concussions among 34 patients: 43 in untreated patients and 1 in a treated patient. For all participants, the concussion rate was 16.3 per 1000 seasons of all sports and 14.8 per 1000 seasons of contact sports. The concussion rate after AC treatment was 4.9 per 1000 seasons of all sports. Three patients experienced sports-related AC rupture or hemorrhage, none of which required surgery or resulted in lasting neurologic symptoms or deficits. The rates of sports-related concussion and cyst rupture in patients with AC in both treated and untreated populations were low. We advocate for a generally permissive posture toward sports participation in this population.

Free-fall drop test with interchangeable surfaces to recreate concussive ice hockey head impacts

Ice hockey has one of the highest concussion rates in sport. During collisions with other players, helmets offer limited protection. Various test protocols exist often requiring various types of laboratory equipment. A simplified test protocol was developed to facilitate testing by more researchers, and modifications to certification standards. Measured kinematics (acceleration vs. time trace shape, peak accelerations, and impact duration) of a Hybrid III headform dropped onto different surfaces were compared to published laboratory representations of concussive impacts. An exemplary comparison of five different helmets, ranging from low (US$50) to high cost (US$300), covering a range of helmet and liner designs, was also undertaken. Different impact conditions were created by changing the impact surface (Modular Elastomer Programmer pad, or 24 to 96 mm of EVAZOTE-50 foam with a Young's modulus of ~ 1 MPa), surface orientation (0 or 45°), impact site, and helmet make/model. With increasing impact surface compliance, peak accelerations decreased and impact duration increased. Impacts onto a 45° anvil covered with 48 mm of foam produced a similar response to reference concussive collisions in ice hockey. Specifically, these impacts gave similar acceleration vs. time trace shapes, while normalized pairwise differences between reference and measured peak acceleration and impact duration, were less than 10% (difference/maximum value), and mean (± SD) of accelerations and duration fell within the interquartile range of the reference data. These results suggest that by modifying the impact surface, a free-fall drop test can produce a kinematic response in a helmeted headform similar to the method currently used to replicate ice hockey collisions. A wider range of impact scenarios, i.e., fall onto different surfaces, can also be replicated. This test protocol for ice hockey helmets could facilitate simplified testing in certification standards and research.

Salt diet Induces Neuroinflammatory Response, Microbiome Dysregulation and Associated with Long-term Anxiety Following Repetitive Closed Head Injury. (S28.003)

<h3>Objective:</h3> Investigate the effects of salt diet on neuroinflammatory response, behavior, and microbiome dysregulation following repetitive closed head injury model. <h3>Background:</h3> Concussions continue to be a prominent public health concern, with an estimated 1.6–3.8 million incidences annually in the United States. Younger populations are experiencing the highest rates of concussion and nearly all athletic endeavors have some risk of concussive injury. Concerns surrounding the potential risks of long-term cognitive and medical outcomes made adolescent traumatic brain injury (TBI) a central focus of public attention. Coupled to these events, recent clinical studies have shown that lifestyle factors, including salt diet, constitute additional risk affecting TBI consequences and neuropathophysiological outcomes. However, the impact of salt diet on the pathophysiology of TBI and whether it exacerbates post-injury outcomes is still largely unknown. <h3>Design/Methods:</h3> We investigated if the exposure to a high salt diet (HSD) would alter hemodynamics, behavior, innate immune response and microbiome diversity after repetitive mild closed head injury in adolescent mice. Mice were injured with a three hit model (3HD) and then maintained on a HSD or standard diet (STD) for 12 weeks. <h3>Results:</h3> We found that HSD didn’t change systolic and diastolic blood pressure, and heart rate compared with STD group. HSD group was associated with worsening anxiety-like behavior at 12 weeks post diet administration. HSD induced microgliosis and proinflammatory microglial transcriptomic signature including upregulation in interferon gamma, Interferon beta, T cells proliferation pathways. Consistently, we found upregulation of proinflammatory Tumor necrotic factor (TNF) in brain compared to Sham-HSD and TBI-STD groups. HSD was the main driver of microbiome dysregulation in both TBI and Sham groups. We found that Eubacterium xylanophilum and Lachnospiraceae bacterium associated with an anxiety phenotype following injury at 12 weeks post diet administration. <h3>Conclusions:</h3> Salt diet associated with increasing risk of worsening anxiety and exacerbating chronic neuroinflammation post repetitive head injury. <b>Disclosure:</b> Dr. Izzy has received publishing royalties from a publication relating to health care. Taha Yahya has nothing to disclose. Dr. Cao has nothing to disclose. Mr. Albastaki has nothing to disclose. Dr. Waed has nothing to disclose. Ms. Chopra has nothing to disclose. Miss EKWUDO has nothing to disclose. Miss Kurdeikaite has nothing to disclose. Ms. Moraes Verissimo has received personal compensation for serving as an employee of Brigham and Women’s Hospital. Ms. Moraes Verissimo has received personal compensation for serving as an employee of Brigham and Women’s Hospital and Harvard Medical School. Ms. Moraes Verissimo has received personal compensation for serving as an employee of Von Medical, Inc.. Ms. Moraes Verissimo has received personal compensation for serving as an employee of Nova Southeastern University. Ms. Moraes Verissimo has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Montachem Company. Dr. Cox has received personal compensation for serving as an employee of Anaerobe Systems. The institution of Dr. Cox has received research support from Infectious Disease Society. The institution of Dr. Cox has received research support from BrightFocus Foundation. Dr. Cox has received intellectual property interests from a discovery or technology relating to health care. Dr. Zafonte has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for MYOMO. Dr. Zafonte has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Kisbee. Dr. Zafonte has received personal compensation in the range of $500-$4,999 for serving as an Editor, Associate Editor, or Editorial Advisory Board Member for Frontiers in Neurology. The institution of Dr. Zafonte has received research support from NIDILRR. The institution of Dr. Zafonte has received research support from NIH. The institution of Dr. Zafonte has received research support from FPHS study. Dr. Zafonte has received publishing royalties from a publication relating to health care. Michael J. Whalen has nothing to disclose.

Epidemiological analysis of pediatric baseball and softball concussions in United States emergency departments

PurposeTo evaluate the epidemiology of concussions in pediatric baseball and softball players. We hypothesized that head-to-ball injuries would be the most common cause of concussions. MethodsThe National Electronic Injury Surveillance System (NEISS) database was used to gather data. Concussions occurring during baseball and softball participation in pediatric patients (4–17 years old) from 2012 to 2021 was gathered. Concussion mechanisms were grouped into 5 categories: head-to-player, head-to-ball, head-to-surface (ground, walls, railings), head-to-bat, and unknown. Linear regression models were used to assess changes in yearly concussion rates over the study period. Results from these models were reported using parameter estimates and the estimated Pearson correlation coefficient. ResultsA weighted total of 54,978 baseball and softball related concussion injuries were analyzed. The average weighted age of our cohort at the time of injury was 13.1 years, with 54.1% (n = 29,761) of concussions occurring in males. The national estimated incidence of concussion injuries decreased non-significantly over the study period (slope estimate = −311 concussions/year, r = −0.625, p-value = 0.054). The majority of weighted national estimate concussions were due to head-to-ball injuries (n = 34,650; 63.0%), followed by head-to-player (n = 8501; 15.5%), head-to-surface (n = 5347; 9.7%), and head-to-bat (n = 5089; 9.3%). On sub-analysis, individuals were grouped into 3 age brackets: 4–8, 9–13, and 14–17 years. The most common mechanism of concussions in children of all ages was head-to-ball. The incidence of head-to-player and head-to-surface injuries increased throughout each age group, while head-to-bat decreased. ConclusionThe incidence of concussions in pediatric baseball and softball athletes has been decreasing non-significantly over our 10-year study period. The most common mechanism of concussions in our study was head-to-ball injuries.