A systematic review of pre-injury anxiety disorder and post-concussion outcomes in youth and young adult athletes.

Pre-injury anxiety disorder may be a risk factor for poor outcomes following sportsrelated concussion. A systematic review was performed to characterize the relationship between pre-injury anxiety disorder and post-concussion symptom presentation and recovery time after sports-related concussions among children, adolescents, and young adults. A PRISMA-compliant literature search was conducted in Ovid MEDLINE, PsycINFO, EMBASE, and Scopus for articles published up to 25 January 2024. The initial query yielded 1358 unique articles. Articles that analyzed the relationship between pre-injury anxiety disorder and post-concussion symptoms and recovery time were included. A final cohort of 11 articles was extracted, comprising a total of 8390 study participants, of whom 921 had a history of pre-injury anxiety disorder. Pre-injury anxiety disorder was associated with prolonged time to return to sports activity and an increased incidence of physical, emotional, cognitive, and sleep-related symptoms. While the results of this review suggest an association between pre-injury anxiety disorder and post-concussion symptoms and recovery time, future studies should be more stringent regarding standardized anxiety disorder definitions, longitudinal assessment of post-concussion symptoms, anxiety disorder subtypes, and anxiety treatment history.

Head Impacts in Collegiate Rodeo Athletes: An Observational Study.

INTRODUCTION: Brain health has been a growing concern across a wide range of contact sports in the last three decades. While most of the early brain health research was focused on identifying and preventing concussions, newer research has found that an accumulation of repetitive head impacts (RHI) are more predictive of long-term brain health than the number of concussions sustained. Consequently, being able to assess RHI in sports despite the lack of outward symptoms has become paramount in promoting the long-term health of athletes. The sport of rodeo has long been regarded as one of the most dangerous contact sports. While some epidemiological research has been done on injury rates in rodeo that has largely backed up its dangerous reputation, no research has been done into RHI in rodeo athletes. METHODS: Head acceleration events (HAE) were measured in collegiate athletes competing in the "Roughstock" events of Bareback Riding, Saddle Bronc Riding and Bull Riding. HAE were recorded using impact monitoring mouthgaurds (iMG) and subsequently confirmed using video verification and submitted to statistical analysis. RESULTS: Rodeo has a high rate of HAE across all the Roughstock events. The Bull Riding experiences the highest magnitude HAE based on both linear and rotational acceleration. These events are primarily the result of the head impacting either the ground or the animal during the dismount phase of the ride. Bareback riding experiences the highest quantity of lower magnitude HAE which mainly result from whiplash-like movement of the head during the ride. CONCLUSIONS: Rodeo athletes experience a high volume of HAE that often reach concerning magnitude. A surprising amount of the HAE are the result not of impacts, but of the whiplash-like movement that is experienced during the rides.

The prevalence of Black/African American individuals in concussion literature: a systematic review and meta-analysis.

Introduction: Comprising approximately 13.6% of the United States population, Black/African American individuals are overrepresented in sports associated with a high risk of concussion. However, there has been a notable absence of systematic reviews examining whether concussion literature accurately reflects the participation and experiences of Black/African American individuals. Therefore, this study aims to systematically review the prevalence of Black/African American individuals compared to White individuals diagnosed with concussions in the literature. Methods: A systematic search was performed across four electronic databases: PubMed, MEDLINE (Ovid), Scopus and Web of Science. Articles were searched from inception to January 5, 2022. Prevalence data were extracted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A meta-analysis of proportions was conducted within hospital records and national survey data. Results: Among 447 identified studies, 11 were included, representing 1,839,901 individuals diagnosed with a concussion, with 73.6% identifying as White and 12.5% identifying as Black/African American. The mean proportion of Black/African American diagnosed with a concussion in hospital records (13.9%; 95% CI [12.8, 15.1]) exceeded that in national surveys (6.4%; 95% CI [3.5, 11.3]) but lower than sports-centered studies (16%). Discussion: These findings underscore the need to address racial disparities in healthcare within the broader context of social determinants of health and systemic inequities. By identifying gaps in the current research, this study lays the foundation for future investigation aimed at elucidating and addressing healthcare disparities.

Subsequent musculoskeletal injury after concussion in National Football League players.

OBJECTIVE: To assess whether National Football League (NFL) players diagnosed with a concussion have an increased risk of injury after return to football. METHODS: A retrospective cohort study analysed the hazard of subsequent time-loss lower extremity (LEX) or any musculoskeletal injury among NFL players diagnosed with a concussion in 2015-2021 preseason or regular season games compared with: (1) all non-concussed players participating in the same game and (2) players with time-loss upper extremity injury. Cox proportional hazards models were adjusted for number of injuries and concussions in the prior year, player tenure and roster position. Additional models accounted for time lost from participation after concussion. RESULTS: There was no statistical difference in the hazards of LEX injury or any musculoskeletal injury among concussed players compared with non-concussed players, though concussed players had a slightly elevated hazard of injury (LEX injury: HR=1.12, 95% CI 0.90 to 1.41; any musculoskeletal injury: HR=1.08, 95% CI: 0.89 to 1.31). When comparing to players with upper extremity injuries, the hazard of injury for concussed players was not statistically different, though HRs suggested a lower injury risk among concussed players (LEX injury: HR=0.78, 95% CI: 0.60 to 1.02; any musculoskeletal injury: HR=0.82, 95% CI: 0.65 to 1.04). CONCLUSION: We found no statistical difference in the risk of subsequent injury among NFL players returning from concussion compared with non-concussed players in the same game or players returning from upper extremity injury. These results suggest deconditioning or other factors associated with lost participation time may explain subsequent injury risk in concussed players observed in some settings after return to play.

Characterization of Mild Traumatic Brain Injury Cohort With Photophobia From the Defense and Veterans Eye Injury and Vision Registry.

INTRODUCTION: Photophobia is a common visual symptom following mild traumatic brain injury (mTBI), which can adversely affect the military readiness and performance of service members (SMs). We employed the Defense and Veterans Eye Injury and Vision Registry (DVEIVR) to identify and describe a cohort of SMs diagnosed with photophobia post-mTBI. The objective of this study was to characterize comorbid conditions and symptoms in an mTBI cohort with photophobia, to assess their co-occurrence, to describe the persistence of photophobia, and to assess the effectiveness of utilization of currently available International Statistical Classification of Diseases and Related Health Problems (ICD) codes in reporting photophobia in this cohort. MATERIALS AND METHODS: The DVEIVR database was searched to identify a cohort of SMs experiencing photophobia after mTBI. Photophobia and other potentially related conditions and symptoms, both coded and descriptive, which were abstracted directly from the medical records of SMs, were found within DVEIVR. The presence of the conditions and symptoms comorbid with photophobia was characterized on both patient and encounter levels. Analysis of co-occurrence of photophobia with these conditions or symptoms was performed on the encounter level using co-occur package in the statistical program R. Persistence of photophobia up to 1 year since the injury was assessed. The utilization of currently available ICD codes for photophobia was analyzed. RESULTS: A total of 639 SMs exhibiting photophobia after mTBI were identified in DVEIVR. Headaches, including migraines, were the most frequently experienced comorbidity affecting 92% of the SMs in the cohort. The second most frequent complaint was dizziness and/or vertigo (53%) followed by nausea (42%), blurry vision (31%), and irritation and discomfort in the eye (17%). In all, 20% of encounters with photophobia had a complaint of headaches, followed by 8.3% of photophobia encounters co-occurring with dizziness and vertigo, 5.7%-with nausea, 4.5%-with blurred vision, and 2.1%-with subjective sensations in the eye. All comorbidities co-occurred with photophobia at probabilities higher than by chance alone. The percentage of mTBI SMs experiencing photophobia declined to 20% at 30 days after the injury, 17% at 3 months, 12% at 6 months, and 7% at 12 months post-injury, respectively. The use of currently available ICD codes for photophobia was very low-only 27.1% of the cohort had at least 1 ICD code recorded in their medical records. CONCLUSIONS: The results of this study support the idea that there is a strong relationship between photophobia and headache after an mTBI. Additional research is warranted to better understand this relationship and its causes so that clinical management improves. The results of this study show a precipitous decline in the numbers of cases of photophobia after mTBI over the first 30 days and a longer-term persistence up to a year in a minority of cases, which is consistent with other research in this field. Various ICD codes, which are currently used to code for photophobia, along with other vision conditions, were not widely used to document photophobia symptoms. It is important to adopt a dedicated ICD code for photophobia to improve the surveillance, data collection, and analysis of this condition.

Safe2Play in youth ice hockey: injury profile and risk factors in a 5-year Canadian longitudinal cohort study.

INTRODUCTION: Ice hockey is a popular global sport with growing participation for boys and girls yet remains a high-risk sport for injury. While the evidence for some risk factors, such as bodychecking policy is well established, other risk factors such as player sex have been understudied. The objectives of this study were to examine factors associated with rates of game-related injury, game-related injury resulting in >7 days of time-loss, and practice-related injury in youth ice hockey. MATERIALS AND METHODS: Safe2Play was a five-year prospective cohort study (2013-2018). All injuries were identified using validated injury surveillance methodology. Multilevel Poisson regression (adjusting for cluster by team and including multiple imputation of missing covariates) was used to estimate incidence rate ratios (IRRs) for player sex, age group, bodychecking policy, year of play, level of play, weight, previous injury within last 12 months, previous lifetime concussion history, and position. RESULTS: A total of 4418 male and female ice hockey players (representing 6584 player-seasons) participating in under-13 (ages 11-12), under-15 (ages 13-14) and under-18 (ages 15-17) age groups were recruited. There were 1184 game-related and 182 practice-related injuries. Factors associated with game-related injury included female sex (IRR = 1.57; 95% CI: 1.18-2.08), previous injury (IRR = 1.46; 95% CI: 1.26-1.70) and lifetime concussion history (IRR = 1.41; 95% CI: 1.23-1.62). Goaltenders had a lower rate of injury (IRR = 0.54; 95% CI: 0.40-0.72) relative to forwards, as did players exposed to policy disallowing bodychecking in games (IRR = 0.44; 95% CI: 0.35-0.55). Female sex (IRR = 1.90; 95% CI: 1.10-3.28) and lifetime concussion history were also significantly associated with practice-related injury (IRR = 1.53; 95% CI: 1.08-2.18). CONCLUSIONS: Based on data from a large 5-year Canadian youth ice hockey longitudinal cohort, several factors associated with injury were identified. Future injury prevention strategies should consider age, sex, previous concussion and injury history, and body checking leagues. Future research in female youth ice hockey including female-only leagues should be a priority to inform prevention strategies in this understudied population.

Mild traumatic brain injury caused by workplace violence in a US workers' compensation system.

OBJECTIVES: Approximately 81% of traumatic brain injury cases are considered to be mild (mTBI), but few studies have reviewed mTBI caused by workplace violence (WPV). This study aimed to (1) determine the incidence of mTBI secondary to WPV in a statewide workers' compensation system using International Classification of Disease codes and (2) analyse and compare factors associated with return-to-work outcomes between WPV mTBI cases versus other mechanisms. METHODS: Using a retrospective cohort of claims data from the California Workers' Compensation Information System during 2015-2019, cases with a return-to-work date were classified as WPV if the injury description contained keywords such as assault, gunpoint, harassed, intimidated, punch, threat, robbery, violent or verbal abuse. RESULTS: Of the 14 089 mTBI claims analysed in this study, 11.2% were caused by WPV. When comparing WPV to non-WPV claims, the variables with statistically significant (p≤0.001) differences were age, income, industry and job class. There were no significant differences between groups for leave duration. In a linear mixed model, the variable of interest (WPV) was not associated with recovery duration after adjusting for other factors. CONCLUSION: To our knowledge, this is the first study to examine WPV mTBI claims in the USA. The findings suggest that the public administration, education and healthcare and social services industries are at higher risk for WPV mTBI. WPV and job class were the only modifiable factors in the model and therefore should be the focus of additional research.

Migraine epidemiology in collegiate student-athletes: Findings from the Concussion Assessment, Research, and Education (CARE) Consortium.

OBJECTIVE: This cross-sectional study evaluated de-identified data from the National Collegiate Athletic Association-Department of Defense Grand Alliance from 2014 to 2020 to determine the prevalence of migraine and migraine medication and to describe differences in migraine prevalence by sex, race, and sport. BACKGROUND: Epidemiological studies can help identify underdiagnosed and undertreated populations. Understanding migraine prevalence in collegiate student-athletes is essential for positive healthcare outcomes including development of prevention and treatment plans. METHODS: From a concussion baseline assessment, participant's self-reported demographics (e.g., age, sex, sport), migraine diagnosis (i.e., yes/no), and migraine medication usage (e.g., yes/no, type) determined prevalence of migraine and medication use in collegiate student-athletes. RESULTS: Migraine was reported in 5.6% (2617/47,060; 95% confidence interval [CI] 5.4%-5.8%) of the student-athletes, with higher prevalence in females, 7.5% (1319/17,628; 95% CI 7.1%-7.9%), than males, 4.6% (1298/28,116; 95% CI 4.4%-4.9%). Medication usage was reported by 36.2% (947/2617; 95% CI 34.3%-38.0%) of individuals with migraine. Migraine reporting differed by race, with Caucasian reporting highest (5.9%; 1990/33,913; 95% CI 5.6%-6.1%) and Asian the lowest (2.7%; 55/2027; 95% CI 2.1%-3.5%). Women's sports, including golf, gymnastics, and lacrosse, and men's diving and squash had higher migraine reporting than other sports. CONCLUSION: Caucasian females reported higher rates than other groups and sport influenced rates of migraine diagnosis.

Pediatric sport and nonsport concussions presenting to emergency departments: injury circumstances, characteristics, and clinical management.

OBJECTIVE: The aim of this study was to compare injury circumstances, characteristics, and clinical management of emergency department (ED) presentations for sports-related concussion (SRC) and non-SRC. METHODS: This multicenter prospective observational study identified patients 5-17 years old who presented to EDs within 24 hours of head injury, with one or more signs or symptoms of concussion. Participants had a Glasgow Coma Scale score of 13-15 and no abnormalities on CT (if performed). Data were stratified by age: young children (5-8 years), older children (9-12 years), and adolescents (13-17 years). RESULTS: Of 4709 patients meeting the concussion criteria, non-SRC accounted for 56.3% of overall concussions, including 80.9% of younger child, 51.1% of older child, and 37.0% of adolescent concussions. The most common mechanism of non-SRC was falls for all ages. The most common activity accounting for SRC was bike riding for younger children, and rugby for older children and adolescents. Concussions occurring in sports areas, home, and educational settings accounted for 26.2%, 21.8%, and 19.0% of overall concussions. Concussions occurring in a sports area increased with age, while occurrences in home and educational settings decreased with age. The presence of amnesia significantly differed for SRC and non-SRC for all age groups, while vomiting and disorientation differed for older children and adolescents. Adolescents with non-SRC were admitted to a ward and underwent CT at higher proportions than those with SRC. CONCLUSIONS: Non-SRC more commonly presented to EDs overall, with SRC more common with increasing age. These data provide important information to inform public health policies, guidelines, and prevention efforts.

Concussion-Related Biomarker Variations in Retired Rugby Players and Implications for Neurodegenerative Disease Risk: The UK Rugby Health Study.

The health and well-being of retired rugby union and league players, particularly regarding the long-term effects of concussions, are of major concern. Concussion has been identified as a major risk factor for neurodegenerative diseases, such as Alzheimer's and Amyotrophic Lateral Sclerosis (ALS), in athletes engaged in contact sports. This study aimed to assess differences in specific biomarkers between UK-based retired rugby players with a history of concussion and a non-contact sports group, focusing on biomarkers associated with Alzheimer's, ALS, and CTE. We randomly selected a sample of male retired rugby or non-contact sport athletes (n = 56). The mean age was 41.84 ± 6.44, and the mean years since retirement from the sport was 7.76 ± 6.69 for participants with a history of substantial concussions (>5 concussions in their career) (n = 30). The mean age was 45.75 ± 11.52, and the mean years since retirement was 6.75 ± 4.64 for the healthy controls (n = 26). Serum biomarkers (t-tau, RBP-4, SAA, Nf-L, and retinol), plasma cytokines, and biomarkers associated with serum-derived exosomes (Aß42, p-tau181, p-tau217, and p-tau231) were analyzed using validated commercial ELISA assays. The results of the selected biomarkers were compared between the two groups. Biomarkers including t-tau and p-tau181 were significantly elevated in the history of the substantial concussion group compared to the non-contact sports group (t-tau: p < 0.01; p-tau181: p < 0.05). Although between-group differences in p-tau217, p-tau231, SAA, Nf-L, retinol, and Aß42 were not significantly different, there was a trend for higher levels of Aß42, p-tau217, and p-tau231 in the concussed group. Interestingly, the serum-derived exosome sizes were significantly larger (p < 0.01), and serum RBP-4 levels were significantly reduced (p < 0.05) in the highly concussed group. These findings indicate that retired athletes with a history of multiple concussions during their careers have altered serum measurements of exosome size, t-tau, p-tau181, and RBP-4. These biomarkers should be explored further for the prediction of future neurodegenerative outcomes, including ALS, in those with a history of concussion.

Association of Sport Helmet Status on Concussion Presentation and Recovery in Male Collegiate Student-Athletes.

Sporting helmets contain force attenuating materials which reduce traumatic head injury risk and may influence sport-related concussion (SRC) sequelae. The purpose of this study was to examine the association of sport helmet status with SRC-clinical presentation and recovery trajectories in men's collegiate athletes. Sport helmet status was based on the nature of sports being either helmeted/non-helmeted. 1070 SRCs in helmeted (HELM) sports (Men's-Football, Ice Hockey, and Lacrosse), and 399 SRCs in non-helmeted (NOHELM) sports (Men's-Basketball, Cheerleading, Cross Country/Track & Field, Diving, Gymnastics, Soccer, Swimming, Tennis, and Volleyball) were analyzed. Multivariable negative binomial regression models analyzed associations between sport helmet status and post-injury cognition, balance, and symptom severity, adjusting for covariate effects (SRC history, loss of consciousness, anterograde/retrograde amnesia, event type). Kaplan-Meier curves evaluated median days to: initiation of return to play (iRTP) protocol, and unrestricted RTP (URTP) by sport helmet status. Log-rank tests were used to evaluate differential iRTP/URTP between groups. Two independent multivariable Weibull accelerated failure time models were used to examine differential iRTP and URTP between groups, after adjusting for aforementioned covariates and symptom severity score. Overall, the median days to iRTP and URTP was 6.3 and 12.0, respectively, and was comparable across NOHELM- and HELM-SRCs. Post-injury symptom severity was lower (Score Ratio 0.90, 95%CI 0.82, 0.98), and cognitive test performance was higher (Score Ratio 1.03, 95%CI 1.02, 1.05) in NOHELM-compared to HELM-SRCs. Estimated time spent recovering to iRTP/URTP was comparable between sport helmet status groups. Findings suggest that the grouping of sports into helmeted and non-helmeted show slight differences in clinical presentation but not recovery.

Avenues for prevention using the epidemiology of sport-related concussion from a large high school surveillance study.

OBJECTIVE: Epidemiology provides fundamental opportunities to protect student-athlete health. The goal of this study was to describe the epidemiology of sport-related concussion (SRC) across 8 years (2015/2016-2022/2023) and compare boys' and girls' sports for SRC incidence and SRC mechanisms. METHODS: This was a retrospective cohort study performed using a statewide high school head injury surveillance system of high school student-athletes (n = 2,182,128; boys, n = 1,267,389; girls, n = 914,739). Exposures of interest included study year and boys and girls in comparable sports. Clinical incidence was calculated by dividing SRC counts in each sport by the number of participants per 100 player-seasons and presented with 95% CIs. The 2019/2020 and 2020/2021 data were included in the analysis, however caution is warranted due to the COVID-19 pandemic. Clinical incidence ratios (CIRs) were estimated for sex-comparable sports, and significance was determined if 95% CIs excluded 1.00. The authors compared mechanism of injury in boys' and girls' comparable sports with chi-square analyses (p < 0.05). RESULTS: Among 25,482 total SRCs, the overall clinical incidence of SRC for all boys and girls was 1.17 (95% CI 1.15-1.18) per 100 player-seasons across all years. Across all years, the overall clinical incidence in boys' sports was 1.34 (95% CI 1.32-1.36) per 100 player-seasons, and 0.93 (95% CI 0.91-0.95) per 100 player-seasons in girls' sports. Boys' sports with the highest clinical incidence included football, ice hockey, and wrestling. Girls' sports with the highest clinical incidence included basketball, soccer, lacrosse, competitive cheer, and gymnastics. Girls consistently had higher SRC rates relative to boys for baseball/softball, basketball, and soccer (CIR range 1.65 [95% CI 1.41-1.93] to 3.32 [95% CI 2.67-4.16]). Girls had lower SRC in lacrosse in 2015/2016 (CIR 0.63, 95% CI 0.40-0.97); no difference in 2016/2017-2020/2021, but had higher clinical incidence in 2021/2022 (CIR 1.69, 95% CI 1.18-2.44) relative to boys. In boys the most common mechanism of SRC occurred from person-to-person contact (n = 8752, 62.8%), whereas girls commonly sustained SRC from person-to-object contact (n = 2369, 33.4%) and from person-to-person contact (n = 2368, 33.4%). There were significant associations between boys' versus girls' sports and mechanism of injury within baseball/softball (χ2 = 12.71, p = 0.005); basketball (χ2 = 36.47, p < 0.001); lacrosse (χ2 = 185.15, p < 0.001); and soccer (χ2 = 122.70, p < 0.001). CONCLUSIONS: These findings can help understand the potential impact of interventions aimed at preventing or reducing SRC. Including girls' sports within this study extends research for a largely underrepresented group.

Sport-related concussions in baseball and softball: do mechanisms of injury affect recovery?

OBJECTIVE: Baseball and softball pose unique risks for sport-related concussion (SRC). Although these are not collision sports, concussions in baseball and softball can nonetheless involve high-speed impacts. In a regional, single-institution cohort of baseball and softball athletes who sustained an SRC, the current study sought to 1) describe the mechanisms of injury that led to SRC, and 2) compare initial symptom burden and recovery metrics across mechanisms, including time to return to learn (RTL), time to symptom resolution, and time to return to play (RTP) by mechanism of injury. METHODS: A retrospective cohort study was performed of baseball and softball athletes 12 to 23 years old who sustained an SRC between November 2017 and April 2022. Mechanisms of injury were divided into two categories: 1) contact mechanism (i.e., what initiated contact with the injured player, such as head-to-ball), and 2) player mechanism (i.e., the action the injured player was performing at the time of injury, such as fielding). The recovery outcomes of time to RTL, symptom resolution, and RTP were compared between mechanisms using bivariate analysis and multivariable regression analysis, controlling for sex, age, time to present to concussion clinic, and initial total symptom score. RESULTS: The sample included 58 baseball and softball players (60.3% female, mean age 16.0 ± 1.9 years). Most SRCs (62.1%) occurred during competition. Head-to-ball (50.0%) was the most common contact mechanism, followed by head-to-head/body (31.0%) and head-to-wall/ground/equipment (17.2%). Fielding (63.8%) was the most common player mechanism, followed by drills (20.7%) and running (13.8%). SRCs sustained in practice had significantly longer RTL (median 10.0 [interquartile range (IQR) 3.3-16.3] vs 4.0 [IQR 2.0-8.0] days; U = 421.5, p = 0.031) and symptom resolution (37.0 [IQR 18.0-90.0] vs 14.0 [IQR 7.0-41.0] days; U = 406.5, p = 0.025) compared with SRCs sustained in competition. Multivariable regression analysis revealed that head-to-wall/ground/equipment contact mechanism was associated with longer RTL (ß = 0.30, 95% CI 0.07-0.54, p = 0.013). CONCLUSIONS: The current study found that SRCs in baseball and softball occurred more often in competition than in practice. Head-to-ball and fielding were the most common contact and player mechanisms, respectively. SRCs sustained in practice were associated with longer time to RTL and symptom resolution, and head-to-wall/ground/equipment was associated with longer RTL in multivariable regression analysis. These results provide empirical data to improve concussion safety in baseball/softball.

Elucidating differences in concussion subtype symptomatology in sports-related versus non-sports-related concussions: a retrospective cohort study.

OBJECTIVE: Postconcussive symptom questionnaires (PCSQs) are often used in concussion patient assessment, yet there is a lack of knowledge as to whether symptom subtype prevalence is dependent on the mechanism of injury (MOI). These subtypes can be defined as cognitive, atlanto-occipital/cervical spine, autonomic, balance, low energy/fatigue/sleep, emotional changes, eyes, and somatic. Using an institutional PCSQ that quantitatively addressed these subtypes, this retrospective study aimed to provide insight into differences in subtype symptomatology between sports-related (SR) and non-sports-related (NSR) injuries. METHODS: Consecutive concussion patients with Glasgow Coma Scale (GCS) score ≥ 13 and ≥ 16 years of age who were treated at a concussion clinic affiliated with an academic level I trauma center in the United States between December 2009 and January 2020 were eligible for inclusion. The authors extracted data on MOI, comorbidities, habits, prior injuries, and PCSQ results. Multivariate analysis of covariance was then conducted to determine the correlations between subtype scores and MOI while considering covariates. RESULTS: Of the 194 patients remaining after applying inclusion and exclusion criteria, analysis included 91 patients in the SR group consisting of 54 (59%) males with mean ± SD (range) age of 20.9 ± 7.3 (16-58) years and 103 patients in the NSR group consisting of 38 (37%) males with mean age of 39.2 ± 14.8 (17-71) years. Demographic characteristics differed significantly between groups. Estimated marginal mean scores were significantly lower in the SR injury group compared to the NSR injury group (with comparing main effects) for the cognitive (p < 0.001), autonomic (p < 0.000), balance (p < 0.025), energy (p < 0.006), emotional (p < 0.000), and total score (p < 0.001) subtypes. Multivariate tests identified three comorbidities that contributed to differences in subtype scores between groups: migraines (p < 0.012), vertigo (p < 0.004), and anxiety (p < 0.038). No significant results were found for the remaining comorbidities of (but not limited to) depression, neuropsychiatric disorders, seizures, syncope, sleep disorder, or none. CONCLUSIONS: The findings indicate that patients who sustain a concussion via an NSR injury present with more severe symptoms but similar concussion subtype frequency as those presenting with SR concussion. This suggests that the MOI may correlate more closely to symptom severity than concussion subtype composition, although larger patient populations with more definitive control of MOI are needed to further elucidate these claims.

Concussions in ice hockey: mixed methods study including assessment of concussions on games missed and cap hit among National Hockey League players, systematic review, and concussion protocol analysis.

OBJECTIVE: Concussions can occur at any level of ice hockey. Incidence estimates of concussions in ice hockey vary, and optimal prevention strategies and return-to-play (RTP) considerations have remained in evolution. The authors performed a mixed-methods study with the aim of elucidating the landscape of concussion in ice hockey and catalyzing initiatives to standardize preventative mechanisms and RTP considerations. METHODS: The authors performed a five-part mixed-methods study that includes: 1) an analysis of the impact of concussions on games missed and income for National Hockey League (NHL) players using a publicly available database, 2) a systematic review of the incidence of concussion in ice hockey, 3) a systematic review of preventative strategies, 4) a systematic review of RTP, and 5) a policy review of documents from major governing bodies related to concussions in sports with a focus on ice hockey. The PubMed, Embase, and Scopus databases were used for the systematic reviews and focused on any level of hockey. RESULTS: In the NHL, 689 players had 1054 concussions from the 2000-2001 to 2022-2023 seasons. A concussion led to a mean of 13.77 ± 19.23 (range 1-82) games missed during the same season. After cap hit per game data became available in 2008-2009, players missed 10,024 games due to 668 concussions (mean 15.13 ± 3.81 per concussion, range 8.81-22.60 per concussion), with a cap hit per game missed of $35,880.85 ± $25,010.48 (range $5792.68-$134,146.30). The total cap hit of all missed games was $385,960,790.00, equating to $577,635.91 per concussion and $25,724,052.70 per NHL season. On systematic review, the incidence of concussions was 0.54-1.18 per 1000 athlete-exposures. Prevention mechanisms involved education, behavioral and cognitive interventions, protective equipment, biomechanical studies, and policy/rule changes. Rules prohibiting body checking in youth players were most effective. Determination of RTP was variable. Concussion protocols from both North American governing bodies and two leagues mandated that a player suspected of having a concussion be removed from play and undergo a six-step RTP strategy. The 6th International Conference on Concussion in Sport recommended the use of mouthguards for children and adolescents and disallowing body checking for all children and most levels of adolescents. CONCLUSIONS: Concussions in ice hockey lead to substantial missed time from play. The authors strongly encourage all hockey leagues to adopt and adhere to age-appropriate rules to limit hits to the head, increase compliance in wearing protective equipment, and utilize high-quality concussion protocols.

Motor vehicle collision characteristics and hospitalization outcomes associated with mild traumatic brain injury and concomitant whiplash injury.

OBJECTIVE: Few large studies have investigated the factors and outcomes related to concomitant injuries occurring alongside mild traumatic brain injury (mTBI) after motor vehicle collisions (MVCs). Thus, the objective of this study was to assess whether MVC characteristics predict which patients with mTBI will have concomitant whiplash injury, and whether concomitant whiplash injury affects care utilization for these patients. METHODS: This retrospective cohort study included 22,213 patients with mTBI after MVC identified from the American College of Surgeons Trauma Quality Programs dataset. A hierarchical logistic regression model was constructed to investigate patient and MVC factors associated with concomitant whiplash injury. Propensity score matching on whiplash status, in conjunction with a multivariable logistic regression model, assessed if concomitant whiplash affected odds of hospitalization. In the subgroup of patients who were hospitalized, associations with hospital length of stay (LOS) and discharge disposition were investigated. RESULTS: The median (IQR) age was 34 (24-51) years, with a median Glasgow Coma Scale score at presentation of 15 (15-15). Patients with concomitant whiplash were older (median 36 years vs 34 years, p = 0.03) and had higher rates of hospitalization (75% vs 64%, p < 0.001). In the hierarchical model for associations with concomitant whiplash injury, patients with blood alcohol content (BAC) greater than the federal driving limit had lower odds of concomitant whiplash (OR 0.63, 95% CI 0.49-0.81) along with those who had airbag deployment (OR 0.80, 95% CI 0.68-0.95), but seatbelt use was associated with greater odds (OR 1.41, 95% CI 1.16-1.71). After matching, concomitant whiplash was independently associated with increased odds of hospitalization (OR 1.67, 95% CI 1.40-1.99) while seatbelt use was associated with decreased odds (OR 0.88, 95% CI 0.81-0.95). Among hospitalized patients, concomitant whiplash was not associated with hospital LOS or discharge disposition. CONCLUSIONS: MVC characteristics such as alcohol consumption and airbag deployment were protective toward development of concomitant whiplash for mTBI patients, while seatbelt use was associated with higher risk. Concomitant whiplash increases the odds of hospitalization for mTBI patients but does not affect hospital LOS or discharge disposition, while seatbelt use is associated with lower rates of hospitalization and a more favorable hospital course. These findings provide context to injury patterns and care provision after a common mechanism of injury.

Examining for gender differences in return to learn following sport-related concussion in high school student athletes.

OBJECTIVE: Prior studies have investigated associations between gender, symptom resolution, and time to return to play following sport-related concussion (SRC). However, there is a notable gap in research regarding the association between gender and return to learn (RTL) in adolescents. Therefore, this study 1) compared the patterns of RTL between boys and girls who are high school student athletes, and 2) evaluated the possible association between gender and time to RTL after adjusting for covariates. METHODS: A retrospective cohort study of a prospective surveillance program that monitored concussion recovery of athletes in high schools throughout the state of Maine between February 2015 and January 2023 was performed. The primary independent variable was gender, dichotomized as boys and girls. The primary outcome was time to RTL, defined by the number of days for an athlete to return to school without accommodations. Mann-Whitney U-tests were used to compare RTL between the boys and girls. Each athlete's RTL status was dichotomized (i.e., returned vs had not returned) at several time points following injury (i.e., 1, 2, 3, and 4 weeks), and chi-square tests were performed to compare the proportions who achieved RTL between groups. Multivariable linear regression analyses were performed to evaluate the predictive value of gender on RTL. Covariates included age, number of previous concussions, history of learning disability or attention-deficit disorder or attention-deficit/hyperactivity disorder, history of a psychological condition, history of headaches or migraines, initial Sport Concussion Assessment Tool (SCAT3/SCAT5) score, and days to evaluation. RESULTS: Of 895 high school athletes, 488 (54.5%) were boys and 407 (45.5%) were girls. There was no statistically significant difference in median [IQR] days to RTL between genders (6.0 [3.0-11.0] vs 6.0 [3.0-12.0] days; U = 84,365.00, p < 0.375). A greater proportion of boys successfully returned to learn without accommodations by 3 weeks following concussion (93.5% vs 89.4%; χ2 = 4.68, p = 0.030), but no differences were found at 1, 2, or 4 weeks. A multivariable model predicting days to RTL showed that gender was not a significant predictor of RTL (p > 0.05). Longer days to evaluation (ß = 0.10, p = 0.021) and higher initial SCAT3/SCAT5 scores (ß = 0.15, p < 0.001) predicted longer RTL. CONCLUSIONS: In a cohort of high school athletes, RTL did not differ between boys and girls following SRC. Gender was not a significant predictor of RTL. Longer days to evaluation and higher initial symptom scores were associated with longer RTL.

SCAT5 baseline values, test-retest reliability, and reliable change metrics in high school athletes.

OBJECTIVE: In the United States, more than 1 million sport-related concussions afflict children annually, with many cases undetected or unreported. The Sport Concussion Assessment Tool (SCAT) is widely used to detect concussions in high school, collegiate, and professional sports. The objective of this study was to establish baseline values for the SCAT version 5 (SCAT5) in high school athletes. METHODS: Baseline SCAT5 evaluations were conducted in students (ages 14-19 years) from 19 high schools in central Illinois who were participating in various school-sponsored sports. The SCAT5 evaluations were retrospectively extracted from the electronic medical record system for analysis. Statistical analyses included the Wilcoxon rank-sum test for continuous variables and the chi-square test for categorical variables, considering significance at p < 0.05. Test-retest reliability at < 6 months, 10-14 months, and 16-20 months was computed using intraclass correlation and Spearman's rho (ρ). Reliable change indices are provided using the Iverson formula. RESULTS: A total of 2833 unique athletes were included, and the average age was 15.5 ± 1.14 (SD) years. There were 721 female (25.5%) and 2112 male (74.5%) athletes. Students ≥ 15 years old had more prior concussions (p < 0.001), and male athletes were more frequently hospitalized for head injury (p = 0.013). Female athletes exhibited a significantly higher prevalence of mood disorders (14.7% vs 4.6%, p < 0.001), whereas attention-deficit/hyperactivity disorder was more common in male athletes (5.2% vs 13.2%, p < 0.001). Symptom number and severity were significantly greater in female athletes (3.17 ± 4.39 vs 2.08 ± 3.49, p < 0.001; 5.47 ± 9.21 vs 3.52 ± 7.26, p < 0.001, respectively), with mood-related symptoms representing the largest differences. Female athletes and students ≥ 15 years old performed better on most cognitive assessments. Female athletes and students < 15 years old performed better on the modified Balance Error Scoring System (p < 0.001). Test-retest reliability was poor to moderate for most assessment components. Reliable change index cutoff values differed slightly by sex, with female athletes often having a greater cutoff value. CONCLUSIONS: This study underscores the variability of SCAT5 baseline values influenced by age, sex, and medical history among adolescent athletes. It provides a robust dataset, delineating baseline values stratified by sex and age within this demographic. Additionally, the results provide enhanced guidance to clinicians for interpretation of change and reliability of baselines.

The Incidence and Propensity of Head Acceleration Events in a Season of Men's and Women's English Elite-Level Club Rugby Union Matches.

OBJECTIVES: To describe and compare the incidence and propensity of head acceleration events (HAEs) using instrumented mouthguards (iMG) by playing position in a season of English elite-level men's and women's rugby union matches. METHODS: iMG data were collected for 255 men and 133 women from 1,865 and 807 player-matches, respectively, and synchronised to video-coded match footage. Head peak resultant linear acceleration (PLA) and peak resultant angular acceleration (PAA) were extracted from each HAE. Mean incidence and propensity values were calculated across different recording thresholds for forwards and backs in addition to positional groups (front row, second row, back row, half backs, centres, back three) with 95% confidence intervals (CI) estimated. Significance was determined based on 95% CI not overlapping across recording thresholds. RESULTS: For both men and women, HAE incidence was twice as high for forwards than backs across the majority of recording thresholds. HAE incidence and propensity were significantly lower in the women's game compared to the men's game. Back-row and front-row players had the highest incidence across all HAE thresholds for men's forwards, while women's forward positional groups and men's and women's back positional groups were similar. Tackles and carries exhibited a greater propensity to result in HAE for forward positional groups and the back three in the men's game, and back row in the women's game. CONCLUSION: These data offer valuable benchmark and comparative data for future research, HAE mitigation strategies, and management of HAE exposure in elite rugby players. Positional-specific differences in HAE incidence and propensity should be considered in future mitigation strategies.

Playing surface and sport contact status modulate time to lower extremity musculoskeletal injury at a greater level than concussion history among collegiate student-athletes.

OBJECTIVES: While previous investigations have demonstrated a positive correlation between previous concussion and risk of subsequent lower extremity musculoskeletal injury (LEMSKI), the effect of sport- and patient-specific factors on time to injury has not been thoroughly described. This study's main objective was to evaluate the relationship between prior concussion and time to LEMSKI among a population of collegiate student-athletes. Secondary objectives were to evaluate the relationship between playing surface, sport contact status, and biologic sex on time to LEMSKI. We hypothesized that those with previous concussions, those competing on synthetic surfaces, and those competing in collision sports would experience decreased latency to LEMSKI overall. METHODS: A retrospective observational analysis of National Collegiate Athletic Association (NCAA) Division I student-athletes was conducted utilizing a mixed linear model analysis with contrasts. Inclusion criteria included participation in the Pac-12 Health Analytics Program with a documented LEMSKI between 2017 and 2020. Exclusion criteria included concurrent concussion and LEMSKI, injury resulting in serious morbidity or mortality, and incomplete medical record. Participants were classified by whether they sustained a concussion prior to LEMSKI in each athletic season. RESULTS: Of 1179 athletes included, 1140 had no previous concussion and 37 had a previous concussion. There was no observed effect of previous concussion (F â€‹= â€‹0.038; p â€‹= â€‹0.846) on time to LEMSKI overall. Student-athletes competing on constructed surfaces sustained a subsequent LEMSKI 14.5 days sooner (SE â€‹= â€‹5.255; p â€‹= â€‹0.045), and those competing on organic surfaces sustained a subsequent LEMSKI 23.5 days sooner (SE â€‹= â€‹4.018; p â€‹< â€‹0.001) in the season than those competing on synthetic surfaces. Contact sport student-athletes sustained a subsequent LEMSKI 52.1 days sooner than collision sport student-athletes (SE â€‹= â€‹5.248; p â€‹< â€‹0.001), and limited contact sport student-athletes sustained a subsequent LEMSKI 42.29 days sooner than collision sport student-athletes (SE â€‹= â€‹4.463; p â€‹< â€‹0.001). There was no observed effect of biologic sex (F â€‹= â€‹0.602; p â€‹= â€‹0.438) on time to LEMSKI overall. CONCLUSION: There was no observed impact of concussion on time on LEMSKI overall in this collegiate athletic population. Contact sports were associated with decreased time to LEMSK, while synthetic surfaces were associated with increased time to LEMSKI in this population. There was no observed impact of biologic sex on time to LEMSKI. LEVEL OF EVIDENCE: Case-control, level of evidence III.