Exposure to Head Impacts and Cognitive and Behavioral Outcomes in Youth Tackle Football Players Across 4 Seasons

Background: Few studies have examined white matter with diffusion tensor imaging in 8- to 12-year-old collision sport (CS) athletes. Hypothesis: Youth CS athletes will demonstrate change in brain fractional anisotropy (FA) after a season of CS compared with an age-matched noncollision sport (NCS) cohort, and the number, magnitude, and location of hits will correlate with changes in the brain determined via FA for CS athletes. Study Design: Prospective cohort study. Level of Evidence: Level 3. Methods: Thirty-five 8- to 12-year-old males in a youth tackle football league (CS) and 12 males from local swim teams (NCS) were recruited. Participants underwent brain magnetic resonance imaging with FA before and after the football season. Number, magnitude, and direction of head impacts were recorded for CS participants throughout the season. Results: A total of 1905 hits were recorded in the CS group for the season, 341 (17.9%) collected during 7 games and 1564 (82.1%) observed during 31 practices. No significant interaction between group (CS and NCS) and time (pre- and postseason) was observed for FA ( P > 0.05). Correlation analysis revealed a significantly positive and moderate relationship between increase of left cingulate cortex (CgC) FA from pre- to postseason and the total magnitude of lateral head impacts ( r = 0.40; P = 0.03). Conclusion: There was no significant change in FA measurement of white matter integrity in a cohort of 8- to 12-year-old males after a season of youth football, nor was any difference detected in FA between youth football players and an age-matched cohort of swimmers. There was a significant correlation between total magnitude of hits sustained by youth football players and an increase in FA in the left CgC; whether this is adaptive or pathologic remains unknown. Clinical Relevance: These data can be used within the body of knowledge to counsel patients regarding the known risks of youth tackle football regarding brain health.

Download Full-text

Subconcussive Head Impacts and Neurocognitive Function Over 3 Seasons of Youth Football

Journal of Child Neurology ◽

10.1177/08830738211004490 ◽

2021 ◽

pp. 088307382110044

Author(s):

Sean C. Rose ◽

Keith Owen Yeates ◽

Joseph T. Nguyen ◽

Patrick M. Ercole ◽

Natalie M. Pizzimenti ◽

...

Keyword(s):

Outcome Measures ◽

Social Adjustment ◽

Neuropsychological Testing ◽

Football Players ◽

Cumulative Impact ◽

Head Impacts ◽

Before And After ◽

History Of ◽

Tackle Football ◽

Neurobehavioral Outcomes

Objective: To determine the association between repetitive subconcussive head impacts and neurobehavioral outcomes in youth tackle football players. Methods: Using helmet-based sensors, we measured head impacts for 3 consecutive seasons of play in 29 male players age 9-11. Cumulative impact g’s were calculated. Players completed a battery of outcome measures before and after each season, including neuropsychological testing, vestibular-ocular sensitivity, and self- and parent-reported measures of symptoms and attention-deficit hyperactivity disorder (ADHD). Results: Average cumulative impact over 3 seasons was 13 900 g. High-intensity hits predicted worse change for self-reported social adjustment ( P = .001). Cumulative impact did not predict change in any of the outcome measures. History of ADHD, anxiety, and depression predicted worse change for self-reported symptoms and social adjustment, independent of head impacts. When players were stratified into 3 groups based on cumulative impact across all 3 seasons, differences in outcome measures existed prior to the start of the first season. These differences did not further increase over the course of the 3 seasons. Conclusion: Over 3 consecutive seasons of youth tackle football, we found no association between cumulative head impacts and neurobehavioral outcomes. Larger sample sizes and longer follow-up times would further assist in characterizing this relationship.

Download Full-text

REPETITIVE HEAD IMPACTS IN YOUTH FOOTBALL: DESCRIPTION AND RELATIONSHIP TO WHITE MATTER STRUCTURE

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967119s00002 ◽

2019 ◽

Vol 7 (3_suppl) ◽

pp. 2325967119S0000

Author(s):

Kurt Nilsson

Keyword(s):

White Matter ◽

Football Players ◽

Average Weight ◽

Average Height ◽

Head Impacts ◽

Repetitive Head Impacts ◽

Number Magnitude ◽

Youth Football ◽

Total Magnitude ◽

Tackle Football

Background: A growing body of evidence has suggested that repetitive head impacts (RHIs) in collision sports produce changes in white matter tracts of athletes as detected by diffusion tensor imaging (DTI). Few studies have examined DTI in 8-12 year old collision sport (CS) athletes, compared them to non-collision sports (NCS) athletes, and correlated findings to accelerometry data. We sought to explore whether, after a single season of participation in youth football, 8-12 year old male CS athletes will: 1) have change in DTI fractional anisotropy (FA) of commonly injured brain regions, 2) have FA differences when compared to an age-matched NCS cohort, and 3) whether there is a correlation between FA and number, magnitude, and location of impacts. Methods: Thirty five 8-12 year old male participants in an organized youth tackle football league were recruited (CS) and matched with twelve 8-12 year old male participants in a local swim team (NCS). Each cohort underwent brain MRI with FA at 5 regions of interest (ROIs) before the youth football season and again immediately following the football season. CS participants’ helmets were instrumented with a force switch sensor to record number, magnitude, and direction of head impacts throughout a single season. Descriptive statistics were calculated for age, height, weight, FA values in all DTI ROIs (Anterior Corona Radiata (ACR), Cingulate Cortex (CgC), Genu of the Corpus Collosum (gCC), Posterior Limb of the Internal Capsule (pllC) and Splenium of the Corpus Collosum (SCC)), magnitude of head impact recorded by accelerometry by season, game and practice, number of hits by season, game and practice and by direction (top, side and rear). A mixed model (group by time) repeated measures MANOVA was conducted to determine if there were any differences in FA between the CS group and the NCS group from pre- to post-season. Correlation and regression analyses were carried out to determine if there was a relationship between the changes of FA from pre- to post-season and number and magnitude of head impacts in the CS group. Results: The average age of participants was: CS: 10.11 years, NCS: 10.17 years. The average height of participants was: CS: 56.89±4.06 inches; NCS: 59.92±5.00 inches (p=0.04). The average weight was: CS: 84.23±21.51 lbs; NCS: 84.75±24.04 lbs, (p>0.05). A total of 1905 hits were recorded for 34 participants in the CS group for the season, 341 (17.9% of total) collected during 7 games and 1564 (82.1% of total) observed during 31 practices. A total of 301 impacts (15.8% of total) with magnitude >= 80 g were collected. For brain ROIs investigated with FA, no significant interaction between group (CS and NCS) and time (pre to post season) was observed (p>0.05). Correlation analysis revealed a significantly positive and moderate relationship between increase of left CgC FA from pre to post season and the total magnitude of lateral head impacts (r=0.40, p=0.03). Conclusion: Our cohort of 8-12 year old male football players sustained fewer impacts when compared to prior accelerometry studies on youth football, although there was a larger number of higher force impacts recorded. There was no significant change in FA measurement of white matter integrity in our youth football players after a single football season, nor was there any difference detected in FA between youth football players and an age-matched cohort of swimmers. There was a significant correlation between total magnitude of hits sustained by youth football players during the season and an increase in FA in the left CgC. Whether this finding is adaptive or pathologic remains unclear. Significance: There is no evidence that 8-12 year old male football players sustain significant white matter changes after a single season of tackle football, although there is positive correlation of FA of the left cingulate gyrus to total magnitude of head impacts over the season.

Download Full-text

American Football: Watch Your Head!

Frontiers for Young Minds ◽

10.3389/frym.2021.652519 ◽

2021 ◽

Vol 9 ◽

Author(s):

Kelly Sarmiento ◽

Dana Waltzman

Keyword(s):

Young People ◽

Brain Injuries ◽

American Football ◽

Football Players ◽

Head Impacts ◽

Or Practice ◽

Tackle Football

Head impacts in American football may lead to brain injuries called concussions. To study head impacts in young people who play American football, we collected data using sensors in mouthguards worn by young American football players. The sensors counted the number of hits and bumps to the head (head impacts) that players of American tackle and flag football got during the football season. We found that tackle football players had about 15 times more head impacts during a game or practice than flag football players had, and 23 times more hard head impacts. Learning more about head impacts in young American football players can help scientists find ways to lower the chances of concussions and other injuries. That way, kids can enjoy the benefits of sports while keeping their brains safe.

Download Full-text

Examining Play Counts and Measurements of Injury Incidence in Youth Football

Journal of Athletic Training ◽

10.4085/1062-6050-52.7.06 ◽

2017 ◽

Vol 52 (10) ◽

pp. 955-965 ◽

Cited By ~ 4

Author(s):

Zachary Y. Kerr ◽

Susan W. Yeargin ◽

Aristarque Djoko ◽

Sara L. Dalton ◽

Melissa M. Baker ◽

...

Keyword(s):

Outcome Measure ◽

Age Groups ◽

Injury Rate ◽

Football Players ◽

Injury Incidence ◽

Injury Rates ◽

Head Impacts ◽

Youth Football ◽

Rate Ratios ◽

Age Range

Context: Whereas researchers have provided estimates for the number of head impacts sustained within a youth football season, less is known about the number of plays across which such impact exposure occurs.Objective: To estimate the number of plays in which youth football players participated during the 2013 season and to estimate injury incidence through play-based injury rates.Design: Descriptive epidemiology study.Setting: Youth football.Patients or Other Participants: Youth football players (N = 2098; age range, 5−15 years) from 105 teams in 12 recreational leagues across 6 states.Main Outcome Measure(s): We calculated the average number of athlete-plays per season and per game using independent-samples t tests to compare age groups (5–10 years old versus 11–15 years old) and squad sizes (<20 versus ≥20 players); game injury rates per 1000 athlete-exposures (AEs) and per 10 000 athlete-plays; and injury rate ratios (IRRs) with 95% confidence intervals (CIs) to compare age groups.Results: On average, youth football players participated in 333.9 ± 178.5 plays per season and 43.9 ± 24.0 plays per game. Age groups (5- to 10-year-olds versus 11- to 15-year-olds) did not differ in the average number of plays per season (335.8 versus 332.3, respectively; t2086.4 = 0.45, P = .65) or per game (44.1 versus 43.7, respectively; t2092.3 = 0.38, P = .71). However, players from smaller teams participated in more plays per season (373.7 versus 308.0; t1611.4 = 8.15, P < .001) and per game (47.7 versus 41.4; t1523.5 = 5.67, P < .001). Older players had a greater game injury rate than younger players when injury rates were calculated per 1000 AEs (23.03 versus 17.86/1000 AEs; IRR = 1.29; 95% CI = 1.04, 1.60) or per 10 000 athlete-plays (5.30 versus 4.18/10 000 athlete-plays; IRR = 1.27; 95% CI = 1.02, 1.57).Conclusions: A larger squad size was associated with a lower average number of plays per season and per game. Increasing youth football squad sizes may help reduce head-impact exposure for individual players. The AE-based injury rates yielded effect estimates similar to those of play-based injury rates.

Download Full-text

Brain trauma exposure for American tackle football players 5 to 9 and 9 to 14 years of age

Journal of Biomechanics ◽

10.1016/j.jbiomech.2021.110689 ◽

2021 ◽

pp. 110689

Author(s):

J. Cournoyer ◽

C. Karton ◽

D. Koncan ◽

M.D. Gilchrist ◽

R.C. Cantu ◽

...

Keyword(s):

Trauma Exposure ◽

Brain Trauma ◽

Football Players ◽

Tackle Football

Download Full-text

A Qualitative Study of Youth Football Coaches’ Perception of Concussion Safety in American Youth Football and Their Experiences With Implementing Tackling Interventions

International Sport Coaching Journal ◽

10.1123/iscj.2020-0004 ◽

2020 ◽

pp. 1-9

Author(s):

Kelly Sarmiento ◽

Dana Waltzman ◽

Kelley Borradaile ◽

Andrew Hurwitz ◽

Kara Conroy ◽

...

Keyword(s):

Head Injuries ◽

Young Age ◽

Long Term Effects ◽

Head Impacts ◽

Football Coaches ◽

Youth Athletes ◽

Risks And Benefits ◽

Youth Football ◽

Tackle Football

Due in part to concern about the potential long-term effects of concussion and repetitive head injuries in football, some programs have implemented tackling interventions. This paper explores youth football coaches’ perception of football safety and their experiences implementing these interventions aimed at athlete safety. Using a qualitative approach, coaches were interviewed by means of a semi-structured protocol that covered: (a) demographics; (b) background and experiences with contact sports; (c) perceived concussion risks and benefits of youth football; (d) experiences with tackling technique; (e) experiences with mouth guard sensors; and (f) personal sources of training related to football safety. Most coaches felt that learning tackling at a young age helped prepare them for their playing later in life and believed that youth should begin playing tackle football at a young age. Coaches were mixed regarding their concerns about the risk for concussion and subconcussive head impacts. Still, most were receptive to changes in rules and policies aimed at making football safer. Findings from this study demonstrate that youth football coaches are important stakeholders to consider when implementing changes to youth football. Understanding coach perceptions and experiences may inform future efforts aimed to educate coaches on rules and policies to make the game safer for youth athletes.

Download Full-text

Association Between Antemortem FLAIR White Matter Hyperintensities and Neuropathology in Brain Donors Exposed to Repetitive Head Impacts

Neurology ◽

10.1212/wnl.0000000000013012 ◽

2021 ◽

pp. 10.1212/WNL.0000000000013012

Author(s):

Madeline Uretsky ◽

Sylvain Bouix ◽

Ronald J. Killiany ◽

Yorghos Tripodis ◽

Brett Martin ◽

...

Keyword(s):

White Matter ◽

White Matter Hyperintensities ◽

Microvascular Disease ◽

Head Impact ◽

American Football ◽

Football Players ◽

Head Impacts ◽

Repetitive Head Impacts ◽

Pathological Correlation ◽

Daily Function

Background and Objectives:Late neuropathologies of repetitive head impacts from contact sports can include chronic traumatic encephalopathy (CTE) and white matter degeneration. White matter hyperintensities (WMH) on fluid attenuated inversion recovery (FLAIR) MRI scans are often viewed as microvascular disease from vascular risk, but might have unique underlying pathologies and risk factors in the setting of repetitive head impacts. We investigated the neuropathological correlates of antemortem WMH in brain donors exposed to repetitive head impacts. The association between WMH, and repetitive head impact exposure and informant-reported cognitive and daily function were tested.Methods:This imaging-pathological correlation study included symptomatic deceased men exposed to repetitive head impacts. Donors had antemortem FLAIR scans from medical records and were without evidence of CNS neoplasm, large vessel infarcts, hemorrhage, and/or encephalomalacia. WMH were quantified using log-transformed values for total lesion volume (TLV), calculated using the lesion prediction algorithm from the Lesion Segmentation Toolbox. Neuropathological assessments included semi-quantitative ratings of white matter rarefaction, cerebrovascular disease, p-tau severity (CTE stage, dorsolateral frontal cortex), and Aβ. Among football players, years of play was a proxy for repetitive head impact exposure. Retrospective informant-reported cognitive and daily function were assessed using the Cognitive Difficulties Scale (CDS) and Functional Activities Questionnaire (FAQ). Regression models controlled for demographics, diabetes, hypertension, and MRI resolution. Statistical significance was defined as p<0.05.Results:The sample included 75 donors: 67 football players and 8 non-football contact sport athletes and/or military veterans. Dementia was the most common MRI indication (64%). Fifty-three (70.7%) had CTE at autopsy. Log-TLV was associated with white matter rarefaction (OR=2.32, 95% CI=1.03,5.24, p=0.04), arteriolosclerosis (OR=2.38, 95% CI=1.02,5.52, p=0.04), CTE stage (OR=2.58, 95% CI=1.17,5.71, p=0.02), and dorsolateral frontal p-tau severity (OR=3.03, 95% CI=1.32,6.97, p=0.01). There was no association with Aβ. More years of football play was associated with log-TLV (b=0.04, 95% CI=0.01,0.06, p=0.01). Greater log-TLV correlated with higher FAQ (unstandardized beta=4.94, 95% CI=0.42,8.57, p=0.03) and CDS scores (unstandardized beta=15.35, 95% CI=-0.27,30.97, p=0.05).Discussion:WMH might capture long-term white matter pathologies from repetitive head impacts, including those from white matter rarefaction and p-tau, in addition to microvascular disease. Prospective imaging-pathological correlation studies are needed.Classification of Evidence:This study provides Class IV evidence of associations between FLAIR white matter hyperintensities, and neuropathological changes (white matter rarefaction, arteriolosclerosis, p-tau accumulation), years of American football play, and reported cognitive symptoms in symptomatic brain donors exposed to repetitive head impacts.

Download Full-text

Baseline profiles of auditory, vestibular, and visual functions in youth tackle football players

Concussion ◽

10.2217/cnc-2019-0008 ◽

2019 ◽

Vol 4 (4) ◽

pp. CNC66

Author(s):

Travis White-Schwoch ◽

Jennifer Krizman ◽

Kristi McCracken ◽

Jamie K Burgess ◽

Elaine C Thompson ◽

...

Keyword(s):

Scoring System ◽

Normative Data ◽

Football Players ◽

Published Data ◽

Frequency Following Response ◽

Youth Athletes ◽

Concussion Management ◽

Tackle Football ◽

Balance Error Scoring System ◽

Balance Error

Aim: Neurosensory tests have emerged as components of sport-related concussion management. Limited normative data are available in healthy, nonconcussed youth athletes. Patients & methods/results: In 2017 and 2018, we tested 108 youth tackle football players immediately before their seasons on the frequency-following response, Balance Error Scoring System, and King-Devick test. We compared results with published data in older and/or and nonathlete populations. Performance on all tests improved with age. Frequency-following response and Balance Error Scoring System results aligned with socioeconomic status. Performance was not correlated across neurosensory domains. Conclusion: Baseline neurosensory functions in seven 14-year-old male tackle football players are consistent with previously published data. Results reinforce the need for individual baselines or demographic-specific norms and the use of multiple neurosensory measures in sport-related concussion management.

Download Full-text

In-season variations in head impact exposure among youth football players

Neurology ◽

10.1212/01.wnl.0000550621.28386.81 ◽

2018 ◽

Vol 91 (23 Supplement 1) ◽

pp. S1.3-S2

Author(s):

Jillian Urban ◽

Mirellie Kelley ◽

Mark Espeland ◽

Elizabeth Davenport ◽

Christopher T. Whitlow ◽

...

Keyword(s):

Head Impact ◽

Cumulative Exposure ◽

Football Players ◽

Sample Mean ◽

Head Impacts ◽

Youth Football ◽

Single Number ◽

Practice Time ◽

Time Frames ◽

Season Variations

Sport-related head impacts are of increasing concern as early evidence has demonstrated a relationship between subconcussive head impact exposure (HIE) experienced in contact sports, such as football, and changes in pre-to post-season imaging and cognitive measures. Cumulative HIE is often measured with a single number that amounts to the total exposure measured over the season and does not give any indication as to how the exposure was accumulated, nor how it varies during the season. Therefore, the objective of this study was to compare HIE during preseason, the first and second halves of the regular season, and playoffs in a sample of youth football players (n = 119, ages 9–13). Athletes were divided into 1 of 4 exposure groups based on quartiles computed from the distribution of risk-weighted cumulative exposure (RWECP). The mean 95th percentile linear and rotational accelerations and impacts per session in practices and games were compared across 4 exposure groups and time frames using mixed effects models. Within games, the sample mean 95th percentile linear and rotational accelerations ranged from 47.2 g and 2,331.3 rad/s2 during preseason to 52.1 g and 2,533.4 rad/s2 during the second half of regular season. Mean impacts per practice increased from preseason to the second half of regular season and declined into playoffs among all exposure groups; however, the variation between time frames was not greater than 2 impacts per practice. Time of season had a significant effect on mean 95th percentile linear and rotational acceleration in games (both p = 0.01) but not on practice accelerations or impacts/session. Mean 95th percentile accelerations for games showed significant interaction effects between exposure group and season segment (linear p = 0.05 and rotational p = 0.04). The results of this study improve our understanding of in-season variations in youth football HIE and may inform important opportunities for future interventions.

Download Full-text