Smith, Aynsley M.

The purpose of this study was to assess the correlations of acceleration measurements between an instrumented hockey helmet and the Hybrid III headform and to determine whether collision with a broad surface affects the correlations between these data. A CCM Vector hockey helmet, instrumented with the Head Impact Telemetry System, was fitted onto an instrumented Hybrid III headform and dropped onto an inclined plate to simulate impacts in hockey. The helmet and headform were dropped from 0.15, 0.30, and 0.60 m at different orientations to create impacts to the vertex, occipital, right, left, and forehead surfaces. Peak linear and rotational acceleration magnitudes and head injury criteria were assessed for each system. Correlations were assessed with the Pearson correlation coefficient, and linear regression models were generated. Relative error was assessed, and results were compared with the Wilcoxon signed rank test. Peak acceleration magnitudes generally had strong mathematical correlations, although a 1:1 linear relationship for rotational acceleration data was not observed. Differences between helmet and head peak acceleration magnitudes were significant. The linear relationship varied according to the impact direction. Instrumented helmet and head data demonstrated a strong mathematical correlation, but measures of linear acceleration generally had better 1:1 agreement than rotational acceleration measures. There is some dependence in the relationship between the helmet and head data on the impact direction, with vertex strikes showing the weakest correlation. Although data generated from the helmet may be useful for interpreting head accelerations experienced by on-ice players, additional analysis of the time-series data should be performed to understand its full utility.

Background/aim To determine if Boys Bantam and Peewee and Girls U14 sustain fewer concussions, head hits, ‘other injuries’ and penalties in hockey tournaments governed by intensified fair play (IFP) than non-intensified fair play (NIFP). Methods A prospective comparison of IFP, a behaviour modification programme that promotes sportsmanship, versus control (non-intensified, NIFP) effects on numbers of diagnosed concussions, head hits without diagnosed concussion (HHWDC), ‘other injuries’, number of penalties and fair play points (FPPs). 1514 players, ages 11–14 years, in 6 IFP (N=950) and 5 NIFP (N=564) tournaments were studied. Results Two diagnosed concussions, four HHWDC, and six ‘other injuries’ occurred in IFP tournaments compared to one concussion, eight HHWDC and five ‘other injuries’ in NIFP. There were significantly fewer HHWDC in IFP than NIFP (p=0.018). However, diagnosed concussions, ‘other injuries’, penalties and FPPs did not differ significantly between conditions. In IFP, a minority of teams forfeited the majority of FPPs. Most diagnosed concussions, HHWDC, and other injuries occurred to Bantam B players and usually in penalised teams that forfeited their FPPs. Conclusions In response to significant differences in HHWDC between IFP and NIFP tournaments, the following considerations are encouraged: mandatory implementation of fair play in regular season and tournaments, empowering tournament directors to not accept heavily penalised teams, and introducing ‘no body checking’ in Bantam.

OBJECT Concussions typically resolve within several days, but in a few cases the symptoms last for a month or longer and are termed persistent postconcussive symptoms (PPCS). These persisting symptoms may also be associated with more serious brain trauma similar to subdural hematoma (SDH). The objective of this study was to investigate the head dynamic and brain tissue responses of injury reconstructions resulting in concussion, PPCS, and SDH. METHODS Reconstruction cases were obtained from sports medicine clinics and hospitals. All subjects received a direct blow to the head resulting in symptoms. Those symptoms that resolved in 9 days or fewer were defined as concussions (n = 3). Those with symptoms lasting longer than 18 months were defined as PPCS (n = 3), and 3 patients presented with SDHs (n = 3). A Hybrid III headform was used in reconstruction to obtain linear and rotational accelerations of the head. These dynamic response data were then input into the University College Dublin Brain Trauma Model to calculate maximum principal strain and von Mises stress. A Kruskal-Wallis test followed by Tukey post hoc tests were used to compare head dynamic and brain tissue responses between injury groups. Statistical significance was set at p < 0.05. RESULTS A significant difference was identified for peak resultant linear and rotational acceleration between injury groups. Post hoc analyses revealed the SDH group had higher linear and rotational acceleration responses (316 g and 23,181 rad/sec2, respectively) than the concussion group (149 g and 8111 rad/sec2, respectively; p < 0.05). No significant differences were found between groups for either brain tissue measures of maximum principal strain or von Mises stress. CONCLUSIONS The reconstruction of accidents resulting in a concussion with transient symptoms (low severity) and SDHs revealed a positive relationship between an increase in head dynamic response and the risk for more serious brain injury. This type of relationship was not found for brain tissue stress and strain results derived by finite element analysis. Future research should be undertaken using a larger sample size to confirm these initial findings. Understanding the relationship between the head dynamic and brain tissue response and the nature of the injury provides important information for developing strategies for injury prevention.

The Minnesota Hockey Education Program (HEP) has three components: skill development, coaching excellence, and Fair Play. The purpose of this paper, however, is to discuss Fair Play, its implementation, success, challenges, and propose a feasible solution. The data collected on Fair Play points earned and decreases in specific penalties suggests positive outcomes attributable to Fair Play, an evidence based program that emphasizes sportsmanship. Closer inspection reveals uneven implementation manifested by: (i) a failure to mandate that invitational tournaments be governed by Fair Play, (ii) not publicizing the influence Fair Play has on determining positioning for end of the season standings, and (iii) the inability to continually promote Fair Play to the continuous turnover of players, parents, and coaches. Annual attrition of a generation of hockey players, parents, and coaches involved when Fair Play was launched contributes to the current lack of awareness about the program. This situation was occurring at the same time we became aware that the prevalence of injuries, such as concussion, had escalated. The less than optimal status of the Fair Play program is not attributed to a lack of effort, but to the fact that volunteer organizations may lack the necessary infrastructure to disseminate information adequately and continuously. A potential solution to the Fair Play knowledge gap is a volunteer safety parent for each team. This parent would be responsible for safety information dissemination (CDC, HUDD, and Fair Play manuals), tracking Fair Play points, ensuring they are posted on the websites, and politely reminding coaches to introduce or review the appropriate on-ice skills training for safety zones, giving and receiving checks, and Head’s Up Don’t Duck (HUDD).

A significant issue in research on the epidemiology of injury relates not to the numerator (injury), but to the denominator: exposure time. Most hockey injury studies “assume” equivalent playing time. This assumption is not problematic for large investigations designed to establish differences in concussion rates between levels of participation. However, the assumption is a serious issue when investigators are testing differences in rules, coaching programs, skills training, and behavioral interventions. Because players are at higher risk for injuries when fatigued, individual exposure time is important. Until recently, analyzing individual playing times for ice hockey teams has been a daunting task, as it involved the hand-written recording of times using a grid and check marks. During the 2011–2012 season, a computer-based program, Time on Ice (TOI), was used to expedite the accurate recording of individual exposure, including shorthanded and power-play situations. The purpose of using TOI software in this study was to ensure that its results were in agreement with the exposure times recorded manually using a paper-and-pencil grid. Preliminary results from six games (12 records of data) showed that exposure time ranged from 6.3 to 26.4 min when using manual recording and 8.3 to 33.2 min when using TOI. These methods were concluded to be in agreement. Now that software has been developed exclusively for the task of tracking time on ice, it is recommended that exposure time be measured when injuries such as concussion are being evaluated and causation is being determined. The Sport Performance Analyzer TOI system is commercially available.

Following the death of a youth hockey coach in a fight with a parent in 2000, the Mayo Clinic Sports Medicine Center and Minnesota Hockey collaborated to implement a three-component Hockey Education Program (HEP). HEP was initiated in 2003 to ensure youth players develop sportsmanship, skills, and a Fair Play approach to the game. Another goal was to decrease attrition of players, coaches, and officials. Coaching Excellence, a component of HEP, is based on 25 years of youth sport research. The HEP manuals Coaches Who Never Lose and Sports and Your Child contain the philosophy, objectives, and guidelines to ensure implementation of HEP components across players, coaches, and parents. The Skill Development component emphasizes learning age-appropriate hockey skills though skill progression. Increasing the practice-to-game ratio to 3–4 practices per game greatly increases the maximum time players skate with the puck during developmental years. Pre- and post-season Skills Challenges allow coaches, players, and parents to gauge improvement, and structure practices to address identified skill deficits. The Fair Play (FP) component emphasizes sportsmanship. Teams earn a FP point each game if they incur less than a preset number of penalty minutes. A coach receiving a game misconduct or a parent∕spectator asked to leave the game will cause the team to forfeit their FP point. FP points are factored into league standings across the state. This past season, 17 678 records of game data were obtained and 25 % (4420) were randomly selected for analysis. The data analysis permits comparison across seasons and changes are made accordingly. Based on four years of data, most Minnesota youth hockey games are played in a sportsmanlike manner. Checking from behind and head contact penalties have decreased since the penalty minutes for these dangerous infractions were increased.

Ice hockey is a fast-paced, aggressive sport whose participants are subject to relatively high rates of injury. Although there is a growing emphasis on the epidemiology of ice hockey research and its application towards reducing injuries, the literature has never been organized into an accessible database. Ice hockey is played in North America, Europe, Scandinavia, the U.K., and several other non-English speaking countries, yet injury reports not written in English are often ignored in review articles. The purpose of this project was to synthesize the existing world literature on ice hockey injuries into a framework of epidemiologic criteria, accessible in an organized, retrievable library. An extensive search of the following databases was done: MEDLINE, BIOSIS, EMBASE, NTIS, CURRENT CONTENTS, DISSERTATION ABSTRACTS, SPORT DISCUS, CINAHL, and WEB OF SCIENCE. Key words used were “ice hockey” and “injuries,” and the search range was 1966 to July 2007. Endnote X (Thompson Corp., Stamford, CT) was used for reference compilation. Eight hundred sixty seven documents were catalogued, from 27 countries in 8 languages. Documents were first categorized by type, including injury (226), equipment (45), case reports (94), review articles (294), editorials (39), or as focusing on the physiological, psychological, or medical aspects of ice hockey (169). Documents were then subdivided by study type and whether they were prospective (117) or retrospective (109). Further subdivisions beyond these levels were based on the inclusion of certain critical epidemiological criteria, including exposure time, a clear definition of “injury,” and the level of play, among others. This comprehensive database should make future ice hockey research more efficient, as well as promote sound epidemiology and a more global perspective.

Abstract Following the death of a youth hockey coach in a fight with a parent in 2000, the Mayo Clinic Sports Medicine Center and Minnesota Hockey collaborated to implement a three-component Hockey Education Program (HEP). HEP was initiated in 2003 to ensure youth players develop sportsmanship, skills, and a Fair Play approach to the game. Another goal was to decrease attrition of players, coaches, and officials. Coaching Excellence, a component of HEP, is based on 25 years of youth sport research. The HEP manuals Coaches Who Never Lose and Sports and Your Child contain the philosophy, objectives, and guidelines to ensure implementation of HEP components across players, coaches, and parents. The Skill Development component emphasizes learning age-appropriate hockey skills though skill progression. Increasing the practice-to-game ratio to 3–4 practices per game greatly increases the maximum time players skate with the puck during developmental years. Pre- and post-season Skills Challenges allow coaches, players, and parents to gauge improvement, and structure practices to address identified skill deficits. The Fair Play (FP) component emphasizes sportsmanship. Teams earn a FP point each game if they incur less than a preset number of penalty minutes. A coach receiving a game misconduct or a parent/spectator asked to leave the game will cause the team to forfeit their FP point. FP points are factored into league standings across the state. This past season, 17 678 records of game data were obtained and 25 % (4420) were randomly selected for analysis. The data analysis permits comparison across seasons and changes are made accordingly. Based on four years of data, most Minnesota youth hockey games are played in a sportsmanlike manner. Checking from behind and head contact penalties have decreased since the penalty minutes for these dangerous infractions were increased.

Abstract Ice hockey is a fast-paced, aggressive sport whose participants are subject to relatively high rates of injury. Although there is a growing emphasis on the epidemiology of ice hockey research and its application towards reducing injuries, the literature has never been organized into an accessible database. Ice hockey is played in North America, Europe, Scandinavia, the U.K., and several other non-English speaking countries, yet injury reports not written in English are often ignored in review articles. The purpose of this project was to synthesize the existing world literature on ice hockey injuries into a framework of epidemiologic criteria, accessible in an organized, retrievable library. An extensive search of the following databases was done: MEDLINE, BIOSIS, EMBASE, NTIS, CURRENT CONTENTS, DISSERTATION ABSTRACTS, SPORT DISCUS, CINAHL, and WEB OF SCIENCE. Key words used were “ice hockey” and “injuries,” and the search range was 1966 to July 2007. Endnote X (Thompson Corp., Stamford, CT) was used for reference compilation. Eight hundred sixty seven documents were catalogued, from 27 countries in 8 languages. Documents were first categorized by type, including injury (226), equipment (45), case reports (94), review articles (294), editorials (39), or as focusing on the physiological, psychological, or medical aspects of ice hockey (169). Documents were then subdivided by study type and whether they were prospective (117) or retrospective (109). Further subdivisions beyond these levels were based on the inclusion of certain critical epidemiological criteria, including exposure time, a clear definition of “injury,” and the level of play, among others. This comprehensive database should make future ice hockey research more efficient, as well as promote sound epidemiology and a more global perspective.