Twardowski, Casey P.

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.

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.