Does disallowing body checking in non-elite 13- to 14-year-old ice hockey leagues reduce rates of injury and concussion? A cohort study in two Canadian provinces

Headgear use in girls' lacrosse-stakeholders not ready for change

Purpose

Mandating headgear for field players in girls' lacrosse to reduce head injuries, including concussion, has been heavily debated. However, research regarding the need and effectiveness of mandated headgear use in girls' lacrosse is still developing. Therefore, this qualitative study aimed to identify the need for and barriers to the development of mandated headgear use policies in girls' lacrosse in Ohio.

Methods

We conducted six virtual focus groups, three with concussion experts (clinicians and researchers) and three with girls' lacrosse stakeholders (high school players, parents, coaches, and officials). A focus group guide was developed to explore study participants' perceptions and opinions on concussion in girls' lacrosse, headgear use among players, and policies and policy development related to headgear use or a headgear mandate. We developed the codebook using an inductive and iterative approach based on focus group transcripts and used ATLAS.TI to code and analyze the transcript data.

Results

Concussion experts and stakeholders understood the potential consequences of concussion but did not perceive concussion as a pervasive problem in girls' lacrosse. The prevention of head and facial injuries was regarded as a potential benefit of headgear use. However, stakeholders expressed that the myriad of arguments discussed opposing mandated headgear use including increased aggressive play and/or targeting, concerns over changes in the game, and cost strongly outweighed the benefits. Finally, both concussion experts and stakeholders identified multiple organizations, including USA Lacrosse, who could act as facilitators and/or barriers to developing, enacting, and implementing headgear policies.

Conclusions

Concussion experts and stakeholders identified possible reasons for headgear use related to injury prevention but also identified several important barriers to the development of a headgear mandate for girls' lacrosse in Ohio.

Sport-related concussion research agenda beyond medical science: culture, ethics, science, policy

The Concussion in Sport Group guidelines have successfully brought the attention of brain injuries to the global medical and sport research communities, and has significantly impacted brain injury-related practices and rules of international sport. Despite being the global repository of state-of-the-art science, diagnostic tools and guides to clinical practice, the ensuing consensus statements remain the object of ethical and sociocultural criticism. The purpose of this paper is to bring to bear a broad range of multidisciplinary challenges to the processes and products of sport-related concussion movement. We identify lacunae in scientific research and clinical guidance in relation to age, disability, gender and race. We also identify, through multidisciplinary and interdisciplinary analysis, a range of ethical problems resulting from conflicts of interest, processes of attributing expertise in sport-related concussion, unjustifiably narrow methodological control and insufficient athlete engagement in research and policy development. We argue that the sport and exercise medicine community need to augment the existing research and practice foci to understand these problems more holistically and, in turn, provide guidance and recommendations that help sport clinicians better care for brain-injured athletes.

What is the Injury Incidence and Profile in Professional Male Ice Hockey? A Systematic Review

BACKGROUND

Professional male ice hockey is characterized by a congested in-season match schedule and by different scenarios where the whole body is exposed to great internal and external forces. Consequently, injuries occur from head to toe. However, there is a lack of data synthesis regarding the injury incidence and profile in this population.

PURPOSE

The aim of this study was to conduct a systematic review to quantify the injury incidence rates in professional male ice hockey.

STUDY DESIGN

Systematic Review.

METHODS

The electronic databases PubMed, CINAHL, Web of Science, ProQuest-Sport medicine & Education Index, and Pro-Quest Dissertation and Thesis were searched utilizing terms related to ice hockey and injuries. Studies were included if they provided the incidence of injury in professional male hockey players and reported injuries in terms of time lost. The modified Newcastle Ottawa Scale for cohort studies and the Strengthening the Reporting of Observational Studies in Epidemiology - Sports Injury and Illness Surveillance Statement were used to assess the methodological quality of the studies.

RESULTS

Eleven studies were included in the review. Match injury incidence ranged from 38 to 88.6 injuries/1000 hours of exposure, whereas training injury incidence varied from 0.4 to 2.6 injuries/1000 hours of exposure. Injuries of traumatic origin accounted for 76% to 96.6% of all injuries, with contusions and lacerations being the most common. Severe injuries accounted for 7.8% - 20% of all injuries. The lower extremities were the most susceptible to injury, comprising 27% to 53.7% of all reported injuries.

CONCLUSION

Professional male ice hockey players are exposed to a substantial risk of injury during competitions, with lower extremities being the most commonly affected body part. The majority of injuries are traumatic and severe injuries account for a notable portion of overall injury cases.

Physical Contact and Suspected Injury Rates in Female versus Male Youth Ice Hockey: A Video-Analysis Study

OBJECTIVE

Canada's national winter sport of ice hockey has high youth participation; however, research surrounding female ice hockey is limited and the injury burden remains high. This study compared rates of head contact (HC), body checking (BC; high-intensity player-to-player contact), and suspected concussion between female and male youth ice hockey.

DESIGN

Cross-sectional.

SETTING

Game video-recordings captured in Calgary, Canada.

PARTICIPANTS

Ten female (BC prohibited) and 10 male (BC permitted) U15 elite AA (13-14-year-old) game video-recordings collected in the 2021 to 22 seasons and 2020 to 21, respectively.

ASSESSMENT OF RISK FACTORS

An analysis of player-to-player physical contact and injury mechanisms using video-analysis.

MAIN OUTCOME MEASURES

Videos were analyzed in Dartfish video-analysis software and all physical contacts were coded based on validated criteria, including HCs (direct [HC1], indirect [HC2]), BC (levels 4-5 on a 5-point intensity scale), and video-identified suspected concussions. Univariate Poisson regression clustering by team-game offset by game-length (minutes) were used to estimate incidence rates and incidence rate ratios (IRR, 95% confidence intervals).

RESULTS

The female game had a 13% lower rate of total physical contacts (IRR = 0.87, 0.79-0.96) and 70% lower rate of BC (IRR = 0.30, 0.23-0.39). There were however no differences in the rates of direct HC (IRR = 1.04, 0.77-1.42) or suspected concussion (IRR = 0.42, 0.12-1.42) between the cohorts. Although prohibited in the female game, only 5.4% of HC1s and 18.6% of BC resulted in a penalty.

CONCLUSIONS

The rates of HC1s and suspected concussions were similar across youth ice hockey. BC rates were lower in the female game, yet still prevalent despite being prohibited.

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

OBJECTIVES

To examine factors associated with rates of game and practice-related concussion in youth ice hockey.

DESIGN

Five-year prospective cohort (Safe2Play).

SETTING

Community arenas (2013-2018).

PARTICIPANTS

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.

ASSESSMENT OF RISK FACTORS

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.

MAIN OUTCOME MEASUREMENTS

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).

MAIN RESULTS

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).

CONCLUSIONS

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.

Can Referees Assess Head Contact Penalties Correctly in Canadian Youth Ice Hockey? A Video Analysis Study

OBJECTIVE

To help address the high concussion burden in Canadian youth ice hockey, our primary objective was to examine the concurrent validity of youth ice hockey referees' ability to assess head contacts (HCs) and associated penalties using video analysis methods after implementation of the "zero tolerance for HC" policy by Hockey Canada.

STUDY DESIGN

Cross-sectional study.

PARTICIPANTS

Certified Level II-III referees in Alberta, Canada.

INTERVENTION

A secured online survey with 60 videos (10 to 15 seconds) containing a player-to-player physical contact with or without a HC from elite U15 (ages 13 to 14) youth ice hockey games.

OUTCOME MEASURES

Survey questions were completed by all referees for each video, including (1). 'Did you see a player-to-player contact?', (2). 'Should a penalty be assessed?', and if yes, (3). 'Which player, penalty type, and penalty intensity?' Referee assessments were compared with a consensus agreement from 2 national and member (top level) gold standard referees for concurrent validity through percent agreement and sensitivity/specificity measures.

RESULTS

Complete-case analysis of 100 referees (131 recruited) showed an overall median agreement of 83.5% (sensitivity = 0.74; specificity = 0.69) with the gold standard. Agreement with the gold standard was highest for HC infractions [85.1% (sensitivity = 0.80; specificity = 0.69)], followed by HC penalty type (81.5%) and penalty intensity (53.7%).

CONCLUSIONS

Concurrent validity through percent agreement was high (>80%) compared with the gold standard for identifying both HC and other infractions; however, it was moderate for penalty intensity. Although knowledge of identifying HCs and penalties in this survey was acceptable, this study suggests in-game factors (eg, game management and positioning) may be a primary limitation for HC enforcement.

Persisting Concussion Symptoms from Bodychecking: Unrecognized Toll in Boys' Ice Hockey

OBJECTIVES

Youth hockey is a high-impact sport and can cause concussions with lasting effects. We hypothesized that important injury prevention information would accrue from longitudinal tracking of concussed players with persisting concussion symptoms (PCS).

METHODS

This case series comprised 87 consecutive concussed ice hockey players aged 10-18 including 66 males and 21 females referred to our Concussion Clinic from 1997 to 2017 and followed longitudinally by clinic visits and questionnaires.

RESULTS

PCS occurred in 70 (80.4%) of 87 concussed players and lasted 1-168 months in males and 3-26 months in females. Bodychecking was the most common concussion mechanism in 34 (39.1%) players and caused PCS in 24 (70.6%) with symptom duration 4.00 [2.75, 14.50] months (median [IQR]). The remaining 53 players had other concussion mechanisms with PCS in 86.8% (p = 0.113) with similar duration (p = 0.848).

CONCLUSIONS

This is the first longitudinal study of concussion with PCS in youth hockey and showed that symptoms can last for several years. Bodychecking was the commonest mechanism of prolonged disability from concussion in boys and girls' hockey with average PCS duration of 12.3 months but several years in some players. The injury prevention message is to raise the age of permitted bodychecking to 18 in boys' hockey from age 13 to 14 where it is currently. In this case series, this change could have prevented the majority of the bodycheck concussions and several years of suffering from PCS and is strong evidence for raising the permitted age for bodychecking in boys' ice hockey to age 18.

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

OBJECTIVES

To evaluate prevention strategies, their unintended consequences and modifiable risk factors for sport-related concussion (SRC) and/or head impact risk.

DESIGN

This systematic review and meta-analysis was registered on PROSPERO (CRD42019152982) and conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

DATA SOURCES

Eight databases (MEDLINE, CINAHL, APA PsycINFO, Cochrane (Systematic Review and Controlled Trails Registry), SPORTDiscus, EMBASE, ERIC0 were searched in October 2019 and updated in March 2022, and references searched from any identified systematic review.

ELIGIBILITY CRITERIA

Study inclusion criteria were as follows: (1) original data human research studies, (2) investigated SRC or head impacts, (3) evaluated an SRC prevention intervention, unintended consequence or modifiable risk factor, (4) participants competing in any sport, (5) analytic study design, (6) systematic reviews and meta-analyses were included to identify original data manuscripts in reference search and (7) peer-reviewed. Exclusion criteria were as follows: (1) review articles, pre-experimental, ecological, case series or case studies and (2) not written in English.

RESULTS

In total, 220 studies were eligible for inclusion and 192 studies were included in the results based on methodological criteria as assessed through the Scottish Intercollegiate Guidelines Network high ('++') or acceptable ('+') quality. Evidence was available examining protective gear (eg, helmets, headgear, mouthguards) (n=39), policy and rule changes (n=38), training strategies (n=34), SRC management strategies (n=12), unintended consequences (n=5) and modifiable risk factors (n=64). Meta-analyses demonstrated a protective effect of mouthguards in collision sports (incidence rate ratio, IRR 0.74; 95% CI 0.64 to 0.89). Policy disallowing bodychecking in child and adolescent ice hockey was associated with a 58% lower concussion rate compared with bodychecking leagues (IRR 0.42; 95% CI 0.33 to 0.53), and evidence supports no unintended injury consequences of policy disallowing bodychecking. In American football, strategies limiting contact in practices were associated with a 64% lower practice-related concussion rate (IRR 0.36; 95% CI 0.16 to 0.80). Some evidence also supports up to 60% lower concussion rates with implementation of a neuromuscular training warm-up programme in rugby. More research examining potentially modifiable risk factors (eg, neck strength, optimal tackle technique) are needed to inform concussion prevention strategies.

CONCLUSIONS

Policy and rule modifications, personal protective equipment, and neuromuscular training strategies may help to prevent SRC.

PROSPERO REGISTRATION NUMBER

CRD42019152982.

Consensus statement on concussion in sport: the 6th International Conference on Concussion in Sport-Amsterdam, October 2022

For over two decades, the Concussion in Sport Group has held meetings and developed five international statements on concussion in sport. This 6th statement summarises the processes and outcomes of the 6th International Conference on Concussion in Sport held in Amsterdam on 27-30 October 2022 and should be read in conjunction with the (1) methodology paper that outlines the consensus process in detail and (2) 10 systematic reviews that informed the conference outcomes. Over 3½ years, author groups conducted systematic reviews of predetermined priority topics relevant to concussion in sport. The format of the conference, expert panel meetings and workshops to revise or develop new clinical assessment tools, as described in the methodology paper, evolved from previous consensus meetings with several new components. Apart from this consensus statement, the conference process yielded revised tools including the Concussion Recognition Tool-6 (CRT6) and Sport Concussion Assessment Tool-6 (SCAT6, Child SCAT6), as well as a new tool, the Sport Concussion Office Assessment Tool-6 (SCOAT6, Child SCOAT6). This consensus process also integrated new features including a focus on the para athlete, the athlete's perspective, concussion-specific medical ethics and matters related to both athlete retirement and the potential long-term effects of SRC, including neurodegenerative disease. This statement summarises evidence-informed principles of concussion prevention, assessment and management, and emphasises those areas requiring more research.

Protective equipment in youth ice hockey: are mouthguards and helmet age relevant to concussion risk?

OBJECTIVES

To compare the incidence rates and odds of concussion between youth ice hockey players based on mouthguard use and helmet age.

MATERIALS AND METHODS

Within a 5-year longitudinal cohort (2013/2014 to 2017/2018) of male and female ice hockey players (ages 11-18; n=3330 players) in Alberta (Canada), we analysed the relationship of equipment and concussion in both a prospective cohort and nested case (concussion) control (acute musculoskeletal injury) approach. The prospective cohort included baseline assessments documenting reported mouthguard use (yes/sometimes, no use), helmet age (newer/<2 years old, older/≥2 years old) and important covariables (weight, level of play, position of play, concussion history, body checking policy), with weekly player participation throughout the season. The nested case-control component used injury reports to document equipment (mouthguard use, helmet age) and other information (eg, mechanism and type of injury) for the injury event. Multivariable mixed effects negative binomial regression (prospective cohort, incidence rate ratios (IRRs)) and multivariable mixed effects logistic regression (nested case-control, odds ratios (OR)) examined the association between equipment and concussion.

RESULTS

Players who reported wearing a mouthguard had a 28% lower concussion rate (IRR=0.72, 95% CI 0.56 to 0.93) and 57% lower odds of concussion (OR=0.43, 95% CI 0.27 to 0.70) compared with non-wearers. There were no associations in the concussion rate (IRR=0.94, 95% CI 0.75 to 1.15) and odds (OR=1.16, 95% CI 0.73 to 1.86) between newer and older helmets.

CONCLUSIONS

Wearing a mouthguard was associated with a lower concussion rate and odds. Policy mandating use should be considered in youth ice hockey. More research is needed to identify other helmet characteristics (eg, quality, fit) that could lower concussion risk.

A video analysis examination of the frequency and type of head impacts for player positions in youth ice hockey and FE estimation of their impact severity

This research employed head impact frequency and frequency of estimated strain to analyse the influence of player position on brain trauma in U15 and U18 youth ice hockey. The methods involved a video analysis of 30 U15 and 30 U18 games where frequency, type of head impact event, and player position during impact was recorded. These impacts were then simulated in the laboratory using physical reconstructions and finite element modelling to determine the brain strains for each impact category. U15 forwards experienced significantly higher head impact frequencies (139) when compared to defenceman (50), with goalies showing the lowest frequency (6) (p < 0.05). U18 forwards experienced significantly higher head impact frequencies (220) when compared to defenceman (92), with goalies having the least frequent head impacts (4) (p < 0.05). The U15 forwards had a significantly higher frequency of head impacts at the very low and med strains and the U18s had higher frequency of head impacts for the very low and low level strains (p < 0.05). Game rule changes and equipment innovation may be considered to mitigate the increased risk faced by forwards compared to other positions in U15 and U18 youth ice hockey.

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

OBJECTIVE

Ringette and female ice hockey are high participation sports in Canada. Despite policies disallowing body checking, both sports have high injury and concussion rates. This study aimed to compare physical contact (PC), head contact (HC), and suspected injury and concussion incidence rates (IRs) in female varsity ringette and ice hockey.

DESIGN

Cross-sectional.

SETTING

Canadian ice arenas.

PARTICIPANTS

Eighteen Canadian female university ringette and ice hockey tournament/playoff games in the 2018-2019/2019-2020 seasons.

ASSESSMENT OF RISK FACTORS

Game video-recordings were analyzed using Dartfish video-analysis software to compare both sports.

MAIN OUTCOME MEASURES

Univariate Poisson regression analyses (adjusted for cluster by team, offset by game-minutes) were used to estimate PC, HC, and suspected injury IRs and incidence rate ratios (IRRs) to compare rates across sports. Proportions of body checks (level 4-5 trunk PC) and direct HC (HC 1 ) penalized were reported.

RESULTS

Analyses of 36 team-games (n = 18 ringette, n = 18 hockey) revealed a 19% lower rate of PCs in ringette than ice hockey {IRR = 0.81 [95% confidence interval (CI), 0.73-0.90]}, but a 98% higher rate of body checking [IRR = 1.98 (95% CI, 1.27-3.09)] compared to ice hockey. Ringette had a 40% higher rate of all HC 1 s [IRR = 1.40 (95% CI, 1.00-1.96)] and a 3-fold higher rate of suspected injury [IRR = 3.11 (95% CI, 1.13-8.60)] than ice hockey. The proportion of penalized body checks and HC 1 s were low across sports.

CONCLUSIONS

Body checking and HC 1 rates were significantly higher in ringette compared to ice hockey, despite rules disallowing both, and very few were penalized. These findings will inform future injury prevention research in ringette and female ice hockey.

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

OBJECTIVE

To examine the association between self-reported and parent-reported attention problems and hyperactivity and rates of injury and concussion in Canadian youth ice hockey players.

DESIGN

Secondary analyses of 2 prospective cohort studies.

SETTING

Canadian youth ice hockey teams.

PARTICIPANTS

Ice hockey players (ages 11-17 years) were recruited by team, over 4 seasons (2011-2016). A combined 1709 players contributing 1996 player-seasons were analyzed (257 players participated in more than one season).

ASSESSMENT OF RISK FACTORS

Data were collected from preseason baseline questionnaires, including child and parent proxy forms of the Behavior Assessment System for Children, second edition.

MAIN OUTCOME MEASURES

Injury and concussion rates and incidence rate ratios (IRR) comparing players with and without self-identified or parent-identified attention problems and hyperactivity, adjusted for covariates (ie, body checking policy, previous injury/concussion, and age) and a random effect for team, were estimated using multiple multilevel negative binomial regression.

RESULTS

When analyzed continuously, rates of concussion increased with higher self-reported and parent-reported measures of attention problems [IRR SELF = 1.025; 95% confidence interval (CI): 1.011-1.040; IRR PARENT = 1.032; 95% CI: 1.008-1.057]. Self-reported hyperactivity was significantly associated with concussion (IRR = 1.021; 95% CI: 1.007-1.035), but parent-reported hyperactivity was not (IRR = 1.005; 95% CI: 0.983-1.028). A T score ≥ 60 cutoff combining attention problems and hyperactivity scores (an estimate of probable attention-deficit hyperactivity disorder) was not significantly associated with rates of injury or concussion.

CONCLUSIONS

Attention problems and hyperactivity may place youth ice hockey players at increased risk of concussion and injury. Preseason assessments could identify players for targeted concussion education and risk reduction strategies.

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

OBJECTIVES

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

METHODS

This 5-year longitudinal cohort included U-15 ice hockey players playing in leagues where policy allowed body checking. Years of body checking experience were classified based on national/local body checking policy. All ice hockey game-related injuries were identified using a validated injury surveillance methodology. Players with a suspected concussion were referred to a study sport medicine physician. Multiple multilevel Poisson regression analysis was performed, adjusting for important covariates and a random effect at a team level (offset by game exposure hours), to estimate injury and concussion incidence rate ratios (IRRs).

RESULTS

In total, 1647 players participated, contributing 1842 player-seasons (195 players participating in two seasons). Relative to no body checking experience, no significant differences were found in the adjusted IRRs for game-related injury for players with 1 year (IRR=1.06; 95% CI: 0.77 to 1.45) or 2+ years (IRR=1.16; 95% CI: 0.74 to 1.84) body checking experience. Similarly, no differences were found in the rates of concussion for players with 1 year (IRR=0.92; 95% CI: 0.59 to 1.42) or 2+ years (IRR=0.69; 95% CI: 0.38 to 1.25) body checking experience.

CONCLUSIONS

Among ice hockey players aged 13-14 years participating in leagues permitting body checking, the adjusted rates of all injury and concussion were not significantly different between those that had body checking experience and those that did not. Based on these findings, no association was found between body checking experience and rates of injury or concussion specifically in adolescent ice hockey.

Does Increasing the Severity of Penalties Assessed in Association With the "Zero Tolerance for Head Contact" Policy Translate to a Reduction in Head Impact Rates in Youth Ice Hockey?

OBJECTIVE

The risk of concussion is high in Canadian youth ice hockey. Aiming to reduce this burden, in 2011, Hockey Canada implemented a national "zero tolerance for head contact (HC)" policy mandating the penalization of any player HC. In 2018 to 2020, Hockey Canada further amended this HC policy including stricter enforcement of severe HCs. This study aimed to compare HC rates, head impact location, and HC enforcement prepolicy, postpolicy, and after policy amendments in elite U15 Canadian youth ice hockey.

DESIGN

This is a prospective cohort study.

SETTING

A collection of events with the video camera located at the highest point near center ice in public ice hockey arenas in Calgary, Alberta.

PARTICIPANTS

A convenience sample of 10 AA U15 games prepolicy (2008-2009), 8 games postpolicy (2013-2014), and 10 games after policy amendments (2020-2021).

INDEPENDENT VARIABLES

An analysis of 3 cohort years regarding the HC-policy implementation and amendments.

MAIN OUTCOME MEASURES

Using Dartfish video-analysis software, all player contacts and HCs [direct (HC1), indirect (eg, boards, ice) (HC2)] were tagged using validated criteria. Univariate Poisson regression clustering by team-game offset by game length (minutes) was used to estimate incidence rates (IR) and incidence rate ratios (IRR) between cohorts.

RESULTS

With additional rule modifications, a 30% reduction in HC1s emerged (IRR 2013-2020 = 0.70, 95% CI, 0.51-0.95). Since the HC-policy implementation, HC1s decreased by 24% (IRR 2008-2020 = 0.76, 95% CI, 0.58-0.99). The proportion of HC1s penalized was similar across cohorts (P 2008-2009 = 14.4%; P 2013-2014 = 15.5%; P 2020-2021 = 16.2%).

CONCLUSIONS

The HC-policy amendments have led to decreased HC1 rates. However, referee enforcement can further boost the HC-policy effectiveness. These findings can help future referee training and potential rule modifications to increase player safety nationally.

Evaluating the Effect of Policy Prohibiting Body Checking on Physical Contacts in U15 and U18 Youth Ice Hockey Leagues

OBJECTIVE

To compare physical contacts (PCs) and head contacts (HCs) in nonelite U15 (ages 13-14) and U18 (ages 15-17) ice hockey players in body checking (BC) and non-BC leagues.

DESIGN

Cohort video analysis study.

SETTING

Ice hockey arenas in Calgary, Canada.

PARTICIPANTS

Players from 13 BC and 13 non-BC games at the nonelite U15 and U18 levels (n = 52 total games).

ASSESSMENT OF RISK FACTORS

Games were videotaped and analyzed to compare PC variables between leagues allowing and prohibiting BC.

MAIN OUTCOME MEASURES

Validated methodology for PC type (trunk PC and other types of PC with limb/stick/head), intensity (low and high intensity), and HC. Incidence rate ratios (IRRs) were estimated using Poisson regression (controlling for cluster by team game and offset by player minutes) to compare the incidence of PCs in BC and non-BC games.

RESULTS

The rate of trunk PCs was lower in the non-BC leagues for both U15 (IRR = 0.50, 99% confidence interval [CI]: 0.43-0.58) and U18 (IRR = 0.56, 99% CI: 0.46-0.67) players. This was most significant for BC contacts (U15: IRR = 0.18, 99% CI: 0.11-0.29; U18: IRR = 0.16, 99% CI: 0.08-0.34), although also significant for body contacts (U15: IRR = 0.54, 99% CI: 0.46-0.64; U18: IRR = 0.58, 99% CI: 0.48-0.70), other PCs, (U15: IRR = 0.60, 99% CI: 0.45-0.78; U18: IRR = 0.71, 99% CI: 0.58-0.88), and HCs (U15: IRR = 0.40, 99% CI: 0.22-0.71; U18: IRR = 0.37, 99% CI: 0.25-0.57).

CONCLUSIONS

The incidence of BC was 82% lower in the U15 and 84% lower in U18 levels not allowing BC, with lower HC and other PC rates also in non-BC leagues. These findings demonstrate high adherence with BC policy change in youth ice hockey.

EFFECTS OF NEUROMUSCULAR TREATMENT ON POSTURAL BALANCE IN ATHLETES RECOVERING FROM THE ANKLE INJURY

ABSTRACT Introduction: Posture is directly related to body balance, and both have great importance in movement. Body posture is affected by several human body factors in space, and neuromuscular athletes’ rehabilitation methods should be designed for an optimal return of postural stability. Objective: Explore the effects of neuromuscular treatment on postural balance rehabilitation of athletes’ ankle injuries. Methods: 20 athletes with functional ankle instability were randomized into experimental and control groups. The experimental group received neuromuscular treatment. The control group maintained standard muscle strength and joint activity rehabilitation exercises. The effects of two rehabilitative procedures were compared by Cumberland ankle instability assessment questionnaire, T-type agility test, and Sargent vertical jump test. Results: Agility after exercise was significantly lower than those before exercise by 0.8 versus 1s; there was no significant difference between the two groups before the experiment. Agility test results of the experimental group were significantly lower than those of the control group (2s). Sargent's vertical jump test results were significantly different from those before the exercise (P < 0.01). Conclusion: The postural balance showed good recovery with the neuromuscular treatment and the rehabilitation method of the athletes after the ankle injury. Evidence Level II; Therapeutic Studies - Investigating the result.

Injuries in Canadian high school boys’ collision sports: insights across football, ice hockey, lacrosse, and rugby

Background

Collision sport participation rates among high school youth in Canada are high. While participation is beneficial for physical and mental well-being, the rates of injury in these sports are high.

Aims

This study aims to compare injury rates and profiles across four common youth collision sports (ice hockey, tackle football, lacrosse, rugby).

Methods

Data from a cross-sectional questionnaire of 2029 high school youth were used to identify male collision sport participants to be included in this secondary analysis (n = 360).

Results

Of the 2029 students who completed the questionnaire, 360 participated in collision-based sports [Ages: 14 (5%), 15 (41%), 16 (25%), 17 (26%), 18 (3%)]. The rates of injury ranged from 12.7 injuries/100 participants/year (rugby) to 33.1 injuries/100 participants/year (ice hockey). Concussion rates ranged from 12.4 (football) to 15.8 (ice hockey) concussions/100 participants/year. Similarities existed in the profile of injuries between sports, with most injuries occurring due to contact with another player (range 57.0% to 87.5%). Injuries to the head (33.3%), wrist/hand (16.0%), shoulder (12.8%), and knee (12.0%) were the most prevalent injury type. Substantial differences in previous playing experience existed between sports.

Discussion

The high rate of injury and concussion reported across each of these sports highlights the need for the introduction of primary prevention strategies in these sports aimed to reduce the risk of injury.

Repeated mild traumatic brain injuries in mice cause age- and sex-specific alterations in dendritic spine density

Mild traumatic brain injuries (mTBI) plague the human population and their prevalence is increasing annually. More so, repeated mTBIs (RmTBI) are known to manifest and compound neurological deficits in vulnerable populations. Age at injury and sex are two important factors influencing RmTBI pathophysiology, but we continue to know little about the specific effects of RmTBI in youth and females. In this study, we directly quantified the effects of RmTBI on adolescent and adult, male and female mice, with a closed-head lateral impact model. We report age- and sex-specific neurobehavioural deficits in motor function and working memory, microglia responses to injury, and the subsequent changes in dendritic spine density in select brain regions. Specifically, RmTBI caused increased footslips in adult male mice as assessed in a beam walk assay and significantly reduced the time spent with a novel object in adolescent male and female mice. RmTBIs caused a significant reduction in microglia density in male mice in the motor cortex, but not female mice. Finally, RmTBI significantly reduced dendritic spine density in the agranular insular cortex (a region of the prefrontal cortex in mice) and increased dendritic spine density in the adolescent male motor cortex. Together, the data provided in this study sheds new light on the heterogeneity in RmTBI-induced behavioural, glial, and neuronal architecture changes dependent on age and sex.

Relationships between aggression, sensation seeking, brain stiffness, and head impact exposure: Implications for head impact prevention in ice hockey

OBJECTIVES

The objectives of this study were to (1) examine the relationship between the number of head impacts sustained in a season of men's collegiate club ice hockey and behavioral traits of aggression and sensation seeking, and (2) explore the neural correlates of these behaviors using neuroimaging.

DESIGN

Retrospective cohort study.

METHODS

Participants (n = 18) completed baseline surveys to quantify self-reported aggression and sensation-seeking tendencies. Aggression related to playing style was quantified through penalty minutes accrued during a season. Participants wore head impact sensors throughout a season to quantify the number of head impacts sustained. Participants (n = 15) also completed baseline anatomical and magnetic elastography neuroimaging scans to measure brain volumetric and viscoelastic properties. Pearson correlation analyses were performed to examine relationships between (1) impacts, aggression, and sensation seeking, and (2) impacts, aggression, and sensation seeking and brain volume, stiffness, and damping ratio, as an exploratory analysis.

RESULTS

Number of head impacts sustained was significantly related to the number of penalty minutes accrued, normalized to number of games played (r = .62, p < .01). Our secondary, exploratory analysis revealed that number of impacts, sensation seeking, and aggression were related to stiffness or damping ratio of the thalamus, amygdala, hippocampus, and frontal cortex, but not volume.

CONCLUSIONS

A more aggressive playing style was related to an increased number of head impacts sustained, which may provide evidence for future studies of head impact prevention. Further, magnetic resonance elastography may aid to monitor behavior or head impact exposure. Researchers should continue to examine this relationship and consider targeting behavioral modification programs of aggression to decrease head impact exposure in ice hockey.

Basketball vs. Hockey-The Changing Face of Sport-Related Injuries in Canada

OBJECTIVE

To characterize and compare the incidence of basketball-related, soccer-related, and hockey-related injuries over a 10-year period.

DESIGN

Cohort analysis of sport-related injuries using multiple Ontario healthcare databases.

SETTING

Emergency department visits in Ontario, Canada.

PATIENTS

Any patient who sustained musculoskeletal injuries sustained while playing basketball, soccer, or hockey between 2006 and 2017 were identified.

ASSESSMENT OF RISK FACTORS

Sport of injury, age, sex, rurality index, marginalization status, and comorbidity score.

MAIN OUTCOME MEASURES

Annual Incidence Density Rates of injury were calculated for each sport, and significance of trends was analyzed by assessing overlap of 95% confidence intervals.

RESULTS

One lakhs eighty five thousand eighty hundred sixty-eight patients (median age: 16 years, interquartile range 13-26) received treatment for sport-related injuries (basketball = 55 468; soccer = 67 021; and hockey = 63 379). The incidence of basketball-related and soccer-related injuries increased from 3.4 (3.3-3.5) to 5.6 (5.5-5.7) and 4.4 (4.3-4.5) to 4.9 (4.8-5) per 10 000 person years, respectively, whereas the incidence of hockey-related injuries decreased from 4.7 (4.6-4.8) to 3.7 (3.6-3.8). Patients with basketball injuries were more marginalized (3.01 ± 0.74) compared with patients with soccer and hockey injuries (2.90 ± 0.75 and 2.72 ± 0.69, respectively).

CONCLUSIONS

Accurate regional epidemiologic information regarding sports injuries can be used to guide policy development for municipal planning and sport program development. The trends and demographic patterns described highlight general and sport-specific injury patterns in Ontario. Populations with the highest incidence of injury, most notably adolescents and men older than 50, may represent an appropriate population for injury risk prevention.

Prevalence of Suspected Concussions Among K-12 Students in Utah: Findings From Utah's Student Injury Reporting System

BACKGROUND

To inform prevention strategies, this study provides incidence, factors, and actions taken when a suspected concussion occurred in K-12 schools in Utah.

METHODS

Data were collected using Utah's Student Injury Reporting System (SIRS) from the academic years 2011-2012 to 2018-2019. SIRS is a unique online system that tracks injuries that occur in the school setting among K-12 students in Utah. Descriptive statistics were computed to characterize students with a suspected concussion. Chi-square (χ² ) analysis looking at characteristics by school level was also conducted.

RESULTS

Over 63,000 K-12 students in Utah sustained an injury at school during the study period. Suspected concussions comprised 10% of all injuries. The prevalence of concussions was highest among males (60.6%) and elementary school students (42.6%) and most often occurred outdoors (57.6%) or on a playground/playfield (33.9%), and in sports- and recreation-related activities (75.1%) (specifically contact sports, 24.0%). Most students with a suspected concussion were absent 1 day or less from school (71.4%) but about 68% were seen by a medical professional. Further, there were differences by school level. Females and students playing contact sports had a higher percentage of suspected concussions as school level increased, whereas males and concussions sustained during school hours had a lower percentage of suspected concussions as school level increased.

CONCLUSIONS

SIRS enables schools in Utah to identify groups at risk for concussion, as well as activities most commonly associated with these injuries, within the school environment. Using this information, schools may implement targeted prevention strategies to protect students.

National Athletic Trainers' Association Position Statement: Reducing Intentional Head-First Contact Behavior in American Football Players

OBJECTIVE

To provide evidence-based recommendations for reducing the prevalence of head-first contact behavior in American football players with the aim of reducing the risk of head and neck injuries.

BACKGROUND

In American football, using the head as the point of contact is a persistent, well-documented, and direct cause of catastrophic head and cervical spine injury. Equally concerning is that repeated head-impact exposures are likely to result from head-first contact behavior and may be associated with long-term neurocognitive conditions such as dementia, depression, and chronic traumatic encephalopathy.

CONCLUSIONS

The National Athletic Trainers' Association proposes 14 recommendations to help the certified athletic trainer, allied health care provider, coach, player, parent, and broader community implement strategies for reducing the prevalence of head-first contact in American football.

Body checking in non-elite adolescent ice hockey leagues: it is never too late for policy change aiming to protect the health of adolescents

OBJECTIVES

The objective of this study is to evaluate the effect of policy change disallowing body checking in adolescent ice hockey leagues (ages 15-17) on reducing rates of injury and concussion.

METHODS

This is a prospective cohort study. Players 15-17 years-old were recruited from teams in non-elite divisions of play (lower 40%-70% by division of play depending on year and city of play in leagues where policy permits or prohibit body checking in Alberta and British Columbia, Canada (2015-18). A validated injury surveillance methodology supported baseline, exposure-hours and injury data collection. Any player with a suspected concussion was referred to a study physician. Primary outcomes include game-related injuries, game-related injuries (>7 days time loss), game-related concussions and game-related concussions (>10 days time loss).

RESULTS

44 teams (453 player-seasons) from non-body checking and 52 teams (674 player-seasons) from body checking leagues participated. In body checking leagues there were 213 injuries (69 concussions) and in non-body checking leagues 40 injuries (18 concussions) during games. Based on multiple multilevel mixed-effects Poisson regression analyses, policy prohibiting body checking was associated with a lower rate of injury (incidence rate ratio (IRR): 0.38 (95% CI 0.24 to 0.6)) and concussion (IRR: 0.49; 95% CI 0.26 to 0.89). This translates to an absolute rate reduction of 7.82 injuries/1000 game-hours (95% CI 2.74 to 12.9) and the prevention of 7326 injuries (95% CI 2570 to 12083) in Canada annually.

CONCLUSIONS

The rate of injury was 62% lower (concussion 51% lower) in leagues not permitting body checking in non-elite 15-17 years old leagues highlighting the potential public health impact of policy prohibiting body checking in older adolescent ice hockey players.

Sport participation and injury rates in high school students: A Canadian survey of 2029 adolescents

INTRODUCTION

The objective of this study is to examine sport and recreational (S&R) activity participation and injury rates (IR) in high school students (ages 14-19).

METHODS

High school students (N = 24 schools, n = 2,029; 958 male, 1,048 female, 23 identified 'other' or missing; ages 14-19) in Alberta completed a web-based survey during class (October 2018-March 2019). Students identified their top three sports for participation in the past year. Primary outcome measures included IR for (a) any S&R-related injury, (b) most serious S&R-related injury resulting in medical attention, and (c) most serious injury resulting in restriction from S&R for at least one day.

RESULTS

In total, 1763/2029 (86.89%) respondents [861/958 (89.87%) male, 886/1048 (84.54%) female, 16/23 (69.57%) identifying as 'other' or missing] participated in an S&R activity in the past year. Top sports for male participation were basketball (33.08%; 95% CI 27.67-39.00), ice hockey (20.46%; 95% CI 14.87-27.47), and soccer (19.42%; 95% CI 15.67-23.80). Top sports for female participation were dance (22.52%; 95% CI 17.98-27.82), basketball (18.32%; 95% CI 14.32-23.14), and badminton (17.84%; 95% CI 13.35-23.43). Of the 1,971 students completing the S&R injury question, 889 reported at least one injury during the past year [(IR = 45.10 injuries/100 students/year (95% CI 39.72-50.61)]. The medical attention IR was 29.09 injuries/100 students/year (95% CI 24.49-34.17) and time loss IR was 36.00 injuries/100 students/year (95% CI 30.47-41.93).

CONCLUSIONS

High school student S&R IRs are high with 29% of adolescents reporting at least one medical attention injury within the past year. Injury prevention strategies targeting youth are necessary. Practical Application: Participation in S&R activities has multiple physical, psychological, and health benefits for adolescents, but some S&R activities also have greater risks of injury. This study informs the next sports to target for implementation of optimal prospective surveillance and injury prevention strategies among high school aged students.

Reality Check 2: The Cost-Effectiveness of Policy Disallowing Body Checking in Non-Elite 13- to 14-Year-Old Ice Hockey Players

Sport-related injuries are the leading cause of injury in youth and are costly to the healthcare system. When body checking is disallowed in non-elite levels of Bantam (ages 13–14 years) ice hockey, the injury rate is reduced, but the impact on costs is unknown. This study compared rates of game injuries and costs among non-elite Bantam ice hockey leagues that disallow body checking to those that did not. Methods: An economic evaluation was conducted alongside a prospective cohort study comparing 608 players from leagues where body checking was allowed in games (Calgary/Edmonton 2014–2015, Edmonton 2015–2016) with 396 players from leagues where it was not allowed in games (Vancouver, Kelowna 2014–2015, Calgary in 2015–2016). The effectiveness measure was rate of game injuries per 1000 player-hours. Costs were estimated based on associated healthcare use within the publicly funded healthcare system as well as privately paid healthcare costs. Probabilistic sensitivity analysis was conducted using bootstrapping. Results: Disallowing body checking reduced the rate of injuries by 4.32 per 1000 player-hours (95% CI −6.92, −1.56) and reduced public and total healthcare system costs by $1556 (95% CI −$2478, −$559) and $1577 (95% CI −$2629, −$500) per 1000 player-hours, respectively. These finding were robust in over 99% of iterations in sensitivity analyses in the public healthcare and the total healthcare system perspectives. There was no statistically significant difference in privately paid healthcare costs (−$65 per 1000 player-hours (95% CI −$220, $99)). Interpretation: Disallowing body checking in non-elite 13–14-year-old ice hockey nationally would prevent injuries and reduce public healthcare costs.

An Economic Evaluation of Disallowing Body Checking in 11- to 12-Year-Old Ice Hockey Leagues

Background:

After a national policy change in 2013 disallowing body checking in Pee Wee ice hockey games, the rate of injury was reduced by 50% in Alberta. However, the effect on associated health care costs has not been examined previously.

Hypothesis:

A national policy removing body checking in Pee Wee (ages 11-12 years) ice hockey games will reduce injury rates, as well as costs.

Study Design:

Cost-effectiveness analysis alongside cohort study.

Level of Evidence:

Level 3.

Methods:

A cost-effectiveness analysis was conducted alongside a cohort study comparing rates of game injuries in Pee Wee hockey games in Alberta in a season when body checking was allowed (2011-2012) with a season when it was disallowed after a national policy change (2013-2014). The effectiveness measure was the rate of game injuries per 1000 player-hours. Costs were estimated based on associated health care use from both the publicly funded health care system and privately paid health care cost perspectives. Probabilistic sensitivity analysis was conducted using bootstrapping.

Results:

Disallowing body checking significantly reduced the rate of game injuries (−2.21; 95% CI [−3.12, −1.31] injuries per 1000 player-hours). We found no statistically significant difference in public health care system (−$83; 95% CI [−$386, $220]) or private health care costs (−$70; 95% CI [−$198, $57]) per 1000 player-hours. The probability that the policy of disallowing body checking was dominant (with both fewer injuries and lower costs) from the perspective of the public health care system and privately paid health care was 78% and 92%, respectively.

Conclusion:

Given the significant reduction in injuries, combined with lower public health care system and private costs in the large majority of iterations in the probabilistic sensitivity analysis, our findings support the policy change disallowing body checking in ice hockey in 11- and 12-year-old ice hockey leagues.

Factors Associated With Clinical Recovery After Concussion in Youth Ice Hockey Players

Background:

The identification of factors associated with clinical recovery in youth after sports-related concussion could improve prognostication regarding return to play (RTP).

Purpose:

To assess factors associated with clinical recovery after concussion in youth ice hockey players.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

Participants were part of a larger longitudinal cohort study (the Safe to Play study; N = 3353). Included were 376 ice hockey players (age range, 11-17 years) from teams in Calgary and Edmonton, Canada, with 425 physician-diagnosed ice hockey–related concussions over 5 seasons (2013-2018). Any player with a suspected concussion was referred to a sports medicine physician for diagnosis, and a Sport Concussion Assessment Tool (SCAT) form was completed. Time to clinical recovery was based on time between concussion and physician clearance to RTP. Two accelerated failure time models were used to estimate days to RTP clearance: model 1 considered symptom severity according to the SCAT3/SCAT5 symptom evaluation score (range, 0-132 points), and model 2 considered responses to individual symptom evaluation items (eg, headache, neck pain, dizziness) of none/mild (0-2 points) versus moderate/severe (3-6 points). Other covariates were time to physician first visit (≤7 and >7 days), age group (11-12, 13-14, and 15-17 years), sex, league type (body checking and no body checking), tandem stance (modified Balance Error Scoring System result ≥4 errors out of 10), and number of previous concussions (0, 1, 2, and ≥3).

Results:

The complete case analysis (including players without missing covariates) included 329 players (366 diagnosed concussions). The median time to clinical recovery was 18 days. In model 1, longer time to first physician visit (>7 days) (time ratio [TR], 1.637 [95% confidence interval (CI), 1.331-1.996]) and greater symptom severity (TR, 1.016 [95% CI, 1.012-1.020]) were significant predictors of longer clinical recovery. In model 2, longer time to first physician visit (TR, 1.698 [95% CI, 1.399-2.062]), headache (moderate/severe) (TR, 1.319 [95% CI, 1.110-1.568]), and poorer tandem stance (TR, 1.249 [95% CI, 1.052-1.484]) were significant predictors of longer clinical recovery.

Conclusion:

Medical clearance to RTP was longer for players with >7 days to physician assessment, poorer tandem stance, greater symptom severity, and moderate/severe headache at first visit.

Incidence of Head Contacts, Penalties, and Player Contact Behaviors in Youth Ice Hockey: Evaluating the “Zero Tolerance for Head Contact” Policy Change

Background:

To reduce the risk of concussion in youth ice hockey, Hockey Canada implemented a national “zero tolerance for head contact” (HC) policy in 2011. A previous cohort study revealed higher concussion rates after this implementation in players aged 11 to 14 years. However, it is unknown whether the elevated risk was due to higher HC rates or factors such as increased concussion awareness and reporting.

Purpose:

To compare the rates of primary and secondary HCs and HC policy enforcement in elite U15 ice hockey leagues (players <15 years) before (2008-2009) and after (2013-2014) the zero-tolerance policy change.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A total of 32 elite U15 games before (n_2008-2009 = 16; 510 players) and after (n_2013-2014 = 16; 486 players) HC policy implementation were video recorded. Videos were analyzed with validated criteria for identifying HC types (primary/direct contact by players [HC1], secondary/indirect contact via boards, glass, or ice surface [HC2]) and other player-to-player contact behavior. Referee-assessed penalties were cross-referenced with the official Hockey Canada casebook, and penalty types were displayed using proportions. Univariate Poisson regression (adjusted for cluster by team game, offset by game length [minutes]) was used to estimate HC incidence rates (IRs) and incidence rate ratios (IRRs) between cohorts.

Results:

A total of 506 HCs were analyzed, 261 before HC policy implementation (IR, 16.6/100 team minutes) and 245 after implementation (IR, 15.5/100 team minutes). The HC1 rate (IRR, 1.05; 95% CI, 0.86-1.28) and HC2 rate (IRR, 0.74; 95% CI, 0.50-1.11) did not significantly differ before versus after implementation. Only 12.0% and 13.6% of HC1s were penalized pre- and postimplementation, respectively. Before implementation, HC1s were commonly penalized as roughing or elbowing penalties (59%), while after implementation, HC1s were penalized with the HC penalty (76%), and only 8% as roughing or elbowing.

Conclusion:

Despite implementation of the “zero tolerance for HC” policy, there was no difference in the rate of HC1s and HC2s or the proportion of HC1 penalized from before to after implementation. This research is instrumental in informing Hockey Canada’s future referee training and rule enforcement modifications.

Fewer US Adolescents Playing Football and Public Health: A Review of Measures to Improve Safety and an Analysis of Gaps in the Literature

Physical activity during adolescence is associated with positive health outcomes, yet only 26% of US middle and high school students report daily physical activity. Moreover, the number of high school students playing a sport is declining, with the largest decline in football. One reason for this decline in playing football may be increased attention to the risk of head injury. For public health, the decline is alarming because football offers a physical activity opportunity for millions of young people every year. In response, efforts have been made to institute measures to enhance the safety of football. The objective of this topical review was to review these measures and the data supporting their effectiveness. We conducted a search of scientific literature supplemented by a web search to identify safety measures. We used the Indiana University library electronic database, PubMed, and web browser searches with specific search terms. In addition to peer-reviewed studies, we searched news stories and reports from sport-related organizations. We summarized the measures and evaluations of effectiveness and categorized the measures by type (game rules, practice guidelines, equipment innovations, strategic initiatives) and target age group (elementary/middle school, high school, college, professional). We found that attempts are being made to improve the safety of football at all levels. However, many measures lack scientific evidence to support their effectiveness. Therefore, researchers need to systematically evaluate safety measures. By implementing evidence-based interventions, we can balance the public health risk of playing football versus the public health risk of continued declines in participation.

Padded Headgear does not Reduce the Incidence of Match Concussions in Professional Men's Rugby Union: A Case-control Study of 417 Cases

Concussion is the most common match injury in rugby union. Some players wear padded headgear, but whether this protects against concussion is unclear. In professional male rugby union players, we examined: (i) the association between the use of headgear and match concussion injury incidence, and (ii) whether wearing headgear influenced time to return to play following concussion. Using a nested case-control within a cohort study, four seasons (2013-2017) of injury data from 1117 players at the highest level of rugby union in England were included. Cases were physician-diagnosed concussion injuries. Controls were other contact injuries (excluding all head injuries). We determined headgear use by viewing video footage. Sixteen percent of cases and controls wore headgear. Headgear use had no significant effect on concussion injury incidence (adjusted odds ratio=1.05, 95% CI: 0.71-1.56). Median number of days absent for concussion whilst wearing headgear was 8 days, compared with 7 days without headgear. Having sustained a concussion in the current or previous season increased the odds of concussion more than four-fold (odds ratio=4.55, 95% CI: 3.77-5.49). Wearing headgear was not associated with lower odds of concussions or a reduced number of days' absence following a concussion.

Active & Safe Central: using a mixed-methods design and the RE-AIM framework to evaluate a sport and recreational injury prevention resource for practitioners in Canada

OBJECTIVES

An online, evidence-based resource was created to support the development of sport and recreational injury prevention programmes. The resource, called Active & Safe Central (www.activesafe.ca), provides evidence-based information across the public health approach for a number of sport and recreational activities. The objective of this project was to evaluate the perceived usefulness of Active & Safe Central as an educational tool.

DESIGN

A mixed-methods study design, guided by the RE-AIM (reach, effectiveness, adoption, implementation and maintenance) framework, was used to evaluate Active & Safe Central.

SETTING

Data were collected using an online survey, available to all users of the site, and focus groups (n=2) that took place in Vancouver and Toronto, Canada.

PARTICIPANTS

Survey respondents (n=87) were recruited online, including parents, coaches, youth and adult athletes, and teachers. Focus group participants (n=16) were key stakeholders and end users, recruited from academia, local health sectors, sport and recreational organisations, and not-for-profit injury prevention organisations.

RESULTS

Post launch, there were 1712 users visiting the website 2306 times (sessions), with the majority representing new users, over returning users (87.5% and 12.5%, respectively). There were 6340 page visits, with the most popular pages including soccer, playgrounds and ice hockey. Active & Safe Central was reported as a credible source of evidence-based sport and recreational information and that the site would be recommended to others. Information collected from focus group participants was used to inform necessary adaptations to the online platform, including critical navigation issues, visualisations and interactivity. The major themes that emerged from focus group and survey data included increased awareness of injury prevention recommendations and that the recommendations would be used in one's own sporting activity and/or practice.

CONCLUSIONS

The results of the evaluation suggest the tool is a useful resource for sport and recreational injury information that has significant potential to impact prevention practice.

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

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; (c) personal relevance risks, safety, and benefits of youth football; (d) experiences with tackling technique; (e) experiences with mouth guard sensors; and (f) opinions on disseminating information on 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.

Future Directions in Sports-Related Concussion Management

This article focuses on 3 concepts that continue to be investigated in the search for the holy grail of concussion-a valid diagnostic test. Imaging advances are discussed with optimism that functional MRI and diffusion tensor imaging may be available clinically. Biomarkers and the use of genetic tests are covered. Sideline accelerometer use may help steer discussions of head trauma risk once technology exists to accurately estimate acceleration of the brain. In the meantime, strategies including allowing athletes to be substituted out of games for an evaluation and video review in elite sports can improve recognition of sports-related concussion.

Microglia dynamics in adolescent traumatic brain injury

Repetitive, mild traumatic brain injuries (RmTBIs) are increasingly common in adolescents and encompass one of the largest neurological health concerns in the world. Adolescence is a critical period for brain development where RmTBIs can substantially impact neurodevelopmental trajectories and life-long neurological health. Our current understanding of RmTBI pathophysiology suggests key roles for neuroinflammation in negatively regulating neural health and function. Microglia, the brain’s resident immune population, play important roles in brain development by regulating neuronal number, and synapse formation and elimination. In response to injury, microglia activate to inflammatory phenotypes that may detract from these normal homeostatic, physiological, and developmental roles. To date, however, little is known regarding the impact of RmTBIs on microglia function during adolescent brain development. This review details key concepts surrounding RmTBI pathophysiology, adolescent brain development, and microglia dynamics in the developing brain and in response to injury, in an effort to formulate a hypothesis on how the intersection of these processes may modify long-term trajectories.

Sexually Dimorphic Behavioral and Genetic Outcomes Associated With Administration of TA65 (A Telomerase Activator) Following Repetitive Traumatic Brain Injury: A Pilot Study

Children and adolescents have the highest rates of traumatic brain injury (TBI), with mild TBI (mTBI) accounting for most of these injuries. This demographic also often suffers from post-injury symptomologies that may persist for months. Telomere length (TL) has previously been used as a marker for outcomes following repetitive mild TBI (RmTBI) and it may be possible that telomere elongation can reduce post-traumatic behavioral impairments. Telomerase activator-65 (TA-65) is a telomerase small-molecule activator purified from the root of Chinese herbs that has been anecdotally reported to have anti-aging and life-extending potential. We hypothesized that RmTBI would shorten TL but administration of TA-65 would reverse RmTBI-induced telomere shortening and behavioral deficits. Male and female Sprague-Dawley rats were orally administered TA-65 or a placebo substance for 30 consecutive days [postnatal day (P) 25–55]. Following the injury protocol (mTBIs on P33, 36, and 40), rats went through a behavioral test battery designed to examine symptomologies commonly associated with mTBI (balance and motor coordination, exploratory behavior, short-term working memory, and anxiety- and depressive-like behaviors). TL in ear and brain tissue (prefrontal cortex and hippocampus) and relative expression of TERT and Tep1 via qPCR were assessed 15 days following the last injury. We observed a heterogenous response between males and females, with TA65 administration resulting in increased mRNA expression of TERT and Tep1 in female rats that experienced RmTBI, which was accompanied by some functional recovery on motor behavior and footslips in the beam walk task and depressive-like behavior in the forced swim task.

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

Objectives

Most concussions in rugby union occur during tackles. We investigated whether legislation to lower maximum tackle height would change tackle behaviour, and reduce concussion incidence rate.

Methods

In an observational evaluation using a prospective cohort design, 12 elite men’s teams played in two competitions during the 2018/2019 season. The Championship (90 games) retained standard Laws of Rugby for the tackle; the Championship Cup (36 games) used revised laws—the maximum tackle height was lowered from the line of the shoulders on the ball carrier to the line of the armpits. Videos of tackles were analysed for ball carrier and tackler behaviour. Injury data were collected using standardised methods.

Results

In the lowered tackle height setting, there was a significantly lower proportion of tackles; (1) in which ball carriers (rate ratio (RR) 0.83, 95% CI 0.79 to 0.86) and tacklers (RR 0.80, 95% CI 0.76 to 0.84) were upright, (2) in which the tackler’s initial contact was to the ball carrier’s head or neck (RR 0.70, 95% CI 0.58 to 0.84) and (3) in which initial contact was above the line of the ball carrier’s armpit (RR 0.84, 95% CI 0.80 to 0.88). Concussion incidence rate did not differ between conditions (RR 1.31, 95% CI 0.85 to 2.01). Unexpectedly, compared with the standard tackle height setting, tacklers in the lowered tackle height setting were themselves concussed at a higher rate as measured by; (1) incidence (RR 1.90, 95% CI 1.05 to 3.45) and (2) concussions per 1000 tackles (2.09, 95% CI 1.15 to 3.80).

Conclusions

Legislating to lower the height of the tackle meant that tacklers made contact with the ball carrier’s head and neck 30% less often. This did not influence concussion incidence rates. Tacklers in the lowered tackle height setting suffered more concussions than did tacklers in the standard tackle height setting.