Head Impact Biomechanics Differ Between Girls and Boys Youth Ice Hockey Players

Background: Body checking is the most common injury mechanism in ice hockey. Rule changes have sought to mitigate body checking exposure among youth players. In 2011, USA Hockey changed the legal body checking age from Pee Wee (11/12-year-olds) to Bantam (13/14-year-olds). Interestingly, Bantam players with checking experience during Pee Wee had a lower concussion risk relative to Bantam players without checking experience in a sample of Canadian youth hockey players. Understanding the head impact biomechanics underlying these findings could further elucidate the consequences of this rule change. Purpose: To determine the association between Pee Wee checking exposure and head impact biomechanics in a cohort of Bantam players. Methods: We prospectively collected data on Bantam ice hockey players during the 2006/07-2009/10 seasons and the 2012-2013 season. The 2006/07-2009/10 cohort (n= 61, age=13.9±0.5 years, height=168.2±8.7 cm, mass=59.9±10.4 kg) was allowed to body check (BC) as a Pee Wee player. The 2012-2013 cohort (n=15, age=13.3±0.4 years, height=167.5±7.4 cm, mass=57.5±8.6 kg) was not permitted to body check (NBC) as a Pee Wee player. Over the course of each season, head impacts were measured using in-helmet accelerometers. Only head impacts with linear acceleration ≥10 g were included in our analysis. Main outcome measures were mean linear acceleration (g) and rotational acceleration (rad/s2). Levene’s tests assessed equality of variance between groups. We employed mixed effects models to assess group differences in mean linear and rotational acceleration between BC and NBC groups. Results: The BC and NBC groups did not differ in height (t74=0.28, p=0.78) or mass (t74=0.84, p=0.40). When assessing group differences in head impact biomechanics, the NBC experienced significantly greater linear acceleration (F1,74=4.36, p=0.04) and greater rotational acceleration (F1,74=21.2, p<0.001) relative to the BC group. On average, the NBC group experienced 23.1 ± 0.87 g linear acceleration and 1993.5 ± 68.4 rad/s2 rotational acceleration compared to the BC group, which experienced 21.2 ± 0.30 g linear acceleration and 1615.9 ± 45.2 rad/s2 rotational acceleration. Conclusions: Bantam ice hockey players without body checking experience during their Pee Wee years experienced greater average linear and rotational acceleration relative to players with Pee Wee body checking experience. While removing body checking from Pee Wee ice hockey may reduce short-term injury risk, these athletes may demonstrate more high-risk head impact biomechanics when legally allowed to body check. Future research should continue to examine the influence of policy changes on head impact biomechanics and injury risk in youth ice hockey. [Figure: see text]

Download Full-text

Does Cervical Muscle Strength in Youth Ice Hockey Players Affect Head Impact Biomechanics?

Clinical Journal of Sport Medicine ◽

10.1097/jsm.0b013e31822c8a5c ◽

2011 ◽

Vol 21 (5) ◽

pp. 416-421 ◽

Cited By ~ 50

Author(s):

Jason P Mihalik ◽

Kevin M Guskiewicz ◽

Stephen W Marshall ◽

Richard M Greenwald ◽

J Troy Blackburn ◽

...

Keyword(s):

Muscle Strength ◽

Head Impact ◽

Ice Hockey ◽

Cervical Muscle ◽

Head Impact Biomechanics ◽

Impact Biomechanics ◽

Hockey Players

Download Full-text

Player aggression affects head impact biomechanics in youth ice hockey players

British Journal of Sports Medicine ◽

10.1136/bjsports-2012-092101.52 ◽

2013 ◽

Vol 47 (5) ◽

pp. e1.48-e1

Author(s):

Jason P Mihalik ◽

Kevin M Guskiewicz ◽

Stephen W Marshall

Keyword(s):

Head Impact ◽

Ice Hockey ◽

Head Impact Biomechanics ◽

Impact Biomechanics ◽

Hockey Players

Download Full-text

Effect of On-ice General Aerobic Fitness on Head Impact Biomechanics in Youth Hockey Players

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000401172.95295.c1 ◽

2011 ◽

Vol 43 (Suppl 1) ◽

pp. 426

Author(s):

Jason P. Mihalik ◽

Kevin M. Guskiewicz ◽

Stephen W. Marshall ◽

Robert C. Cantu ◽

J. Troy Blackburn ◽

...

Keyword(s):

Aerobic Fitness ◽

Head Impact ◽

Head Impact Biomechanics ◽

Impact Biomechanics ◽

Hockey Players ◽

Youth Hockey

Download Full-text

Validation of a Helmet-Based System to Measure Head Impact Biomechanics in Ice Hockey

Medicine & Science in Sports & Exercise ◽

10.1249/mss.0b013e3182a32d0d ◽

2014 ◽

Vol 46 (1) ◽

pp. 115-123 ◽

Cited By ~ 46

Author(s):

Mari A. Allison ◽

Yun Seok Kang ◽

John H. Bolte ◽

Matthew R. Maltese ◽

Kristy B. Arbogast

Keyword(s):

Head Impact ◽

Ice Hockey ◽

Head Impact Biomechanics ◽

Impact Biomechanics

Download Full-text

Safe-Play Knowledge, Aggression, and Head-Impact Biomechanics in Adolescent Ice Hockey Players

Journal of Athletic Training ◽

10.4085/1062-6050-51.5.04 ◽

2016 ◽

Vol 51 (5) ◽

pp. 366-372 ◽

Cited By ~ 14

Author(s):

Julianne D. Schmidt ◽

Alice F. Pierce ◽

Kevin M. Guskiewicz ◽

Johna K. Register-Mihalik ◽

Derek N. Pamukoff ◽

...

Keyword(s):

Sports Medicine ◽

Mixed Model ◽

Linear Acceleration ◽

Head Impact ◽

Female Adolescent ◽

Ice Hockey ◽

Impact Frequency ◽

Mixed Model Analysis ◽

Impact Biomechanics ◽

Hockey Players

Context: Addressing safe-play knowledge and player aggression could potentially improve ice hockey sport safety. Objectives: To compare (1) safe-play knowledge and aggression between male and female adolescent ice hockey players and (2) head-impact frequency and severity between players with high and low levels of safe-play knowledge and aggression during practices and games. Design: Cohort study. Setting: On field. Patients or Other Participants: Forty-one male (n = 29) and female (n = 12) adolescent ice hockey players. Intervention(s): Players completed the Safe Play Questionnaire (0 = less knowledge, 7 = most knowledge) and Competitive Aggressiveness and Anger Scale (12 = less aggressive, 60 = most aggressive) at midseason. Aggressive penalty minutes were recorded throughout the season. The Head Impact Telemetry System was used to capture head-impact frequency and severity (linear acceleration [g], rotational acceleration [rad/s2], Head Impact Technology severity profile) at practices and games. Main Outcome Measure(s): One-way analyses of variance were used to compare safe play knowledge and aggression between sexes. Players were categorized as having high or low safe-play knowledge and aggression using a median split. A 2 × 2 mixed-model analysis of variance was used to compare head-impact frequency, and random-intercept general linear models were used to compare head-impact severity between groups (high, low) and event types (practice, game). Results: Boys (5.8 of 7 total; 95% confidence interval [CI] = 5.3, 6.3) had a trend toward better safe-play knowledge compared with girls (4.9 of 7 total; 95% CI = 3.9, 5.9; F1,36 = 3.40, P = .073). Less aggressive male players sustained significantly lower head rotational accelerations during practices (1512.8 rad/s2, 95% CI = 1397.3, 1637.6 rad/s2) versus games (1754.8 rad/s2, 95% CI = 1623.9, 1896.2 rad/s2) and versus high-aggression players during practices (1773.5 rad/s2, 95% CI = 1607.9, 1956.3 rad/s2; F1,26 = 6.04, P = .021). Conclusions: Coaches and sports medicine professionals should ensure that athletes of all levels, ages, and sexes have full knowledge of safe play and should consider aggression interventions for reducing head-impact severity among aggressive players during practice.

Download Full-text

Head Impact Biomechanics in Youth Flag Football: A Prospective Cohort Study

The American Journal of Sports Medicine ◽

10.1177/03635465211026643 ◽

2021 ◽

pp. 036354652110266

Author(s):

Landon B. Lempke ◽

Rachel S. Johnson ◽

Rachel K. Le ◽

Melissa N. Anderson ◽

Julianne D. Schmidt ◽

...

Keyword(s):

Mixed Model ◽

Linear Acceleration ◽

Cross Sectional Study ◽

Head Impact ◽

Rotational Acceleration ◽

Event Type ◽

Level Of Evidence ◽

Cross Sectional ◽

Head Impact Biomechanics ◽

Impact Biomechanics

Background: Youth flag football participation has rapidly grown and is a potentially safer alternative to tackle football. However, limited research has quantitatively assessed youth flag football head impact biomechanics. Purpose: To describe head impact biomechanics outcomes in youth flag football and explore factors associated with head impact magnitudes. Study Design: Cross-sectional study; Level of evidence, 3. Methods: We monitored 52 player-seasons among 48 male flag football players (mean ± SD; age, 9.4 ± 1.1 years; height, 138.6 ± 9.5 cm; mass, 34.7 ± 9.2 kg) across 3 seasons using head impact sensors during practices and games. Sensors recorded head impact frequencies, peak linear ( g) and rotational (rad/s2) acceleration, and estimated impact location. Impact rates (IRs) were calculated as 1 impact per 10 player-exposures; IR ratios (IRRs) were used to compare season, event type, and age group IRs; and 95% CIs were calculated for IRs and IRRs. Weekly and seasonal cumulative head impact frequencies and magnitudes were calculated. Mixed-model regression models examined the association between player characteristics, event type, and seasons and peak linear and rotational accelerations. Results: A total of 429 head impacts from 604 exposures occurred across the study period (IR, 7.10; 95% CI, 4.81-10.50). Weekly and seasonal cumulative median head impact frequencies were 1.00 (range, 0-2.63) and 7.50 (range, 0-21.00), respectively. The most frequent estimated head impact locations were the skull base (n = 96; 22.4%), top of the head (n = 74; 17.2%), and back of the head (n = 66; 15.4%). The combined event type IRs differed among the 3 seasons (IRR range, 1.45-2.68). Games produced greater IRs (IRR, 1.24; 95% CI, 1.01-1.53) and peak linear acceleration (mean difference, 5.69 g; P = .008) than did practices. Older players demonstrated greater combined event–type IRs (IRR, 1.46; 95% CI, 1.12-1.90) and increased head impact magnitudes than did younger players, with every 1-year age increase associated with a 3.78 g and 602.81-rad/s2 increase in peak linear and rotational acceleration magnitude, respectively ( P≤ .005). Conclusion: Head IRs and magnitudes varied across seasons, thus highlighting multiple season and cohort data are valuable when providing estimates. Head IRs were relatively low across seasons, while linear and rotational acceleration magnitudes were relatively high.

Download Full-text