VIDEO ANALYSIS OF HEAD IMPACT SITUATIONS DURING BLIND FOOTBALL GAMES IN TOKYO 2020 PARALYMPIC

S. Tsutsumi¹, J. Sasadai², N. Maeda¹, S. Arima¹, T. Tashiro¹, K. Kaneda¹, M. Yoshimi¹, R. Mizuta¹, H. Ishihara¹, H. Esaki¹, K. Tsuchida¹, T. Terada¹, M. Komiya¹, A. Suzuki², Y. Urabe¹

¹Hiroshima University, Hiroshima, Japan, ²Sports Medical Center, Japan Institute of Sports Sciences (JISS), Tokyo, Japan

Background: Blind football is known as the highest injury rate among all competitions in the past paralympic games (Willick et al., 2013; Derman et al., 2018). In addition, head and neck injuries account for approximately 25% of acute injuries (Webborn et al., 2016). However, few studies have actually focused on head impact for blind football and the lack of specific measures is problematic.

Purpose: To investigate the situations of head impact in blind football games and to clarify basic information for the construction of preventive measures.

Methods: 17 official match videos of the Tokyo 2020 Paralympic games (except for 1 drawn) were obtained from the International Paralympic Committee’s official channel on YouTube (https://www.youtube.com/c/paralympics). The analysis was conducted by three physiotherapists with expertise in para-sports. Prior to this analysis, a pilot test was conducted using actual match videos. Head-to-head impact was defined as a situation in which the head (including the face) made impact with a player or equipment, and head-to-head impact was counted as two cases. The unit of one player participating in one match was defined as athlete-exposure (AE), and the head impact exposure per AE was calculated (Dick et al., 2007). The analysis items were "time of occurrence" (first half/second half), "offensive or defensive situation", "playing situation" (dribbling/scrambling for the ball/kicking/off-the-ball), "playing area" (inside or outside of the penalty area), "impact objects" (opponent/teammate/equipment), "occurring the falls" (presence/absence), "impacted head areas" (front/crown/side/back/face). Statistical analysis was performed by chi-square test and residual analysis with subtests to compare each item with the results of the games (win/loss). Statistical significance was set at p<0.05%.

Results: A total of 827 head impacts were observed, 414 by the winning team and 413 by the losing team, for a total of 48.6 per game. Head impact exposure was 3.84/AE. There were significant differences between the winning and losing teams in "playing area," "occurring the falls," and "impacted head area" (p<0.05). Residual analysis showed that the losing team had a significantly higher rate of impact in the penalty area, with falls, and impact with the back of the head (p<0.05). There were no significant differences in "time of occurrence," "offensive or defensive situation," "playing situation," and "impact objects”.

Conclusions: The head impact exposure of this study was higher than healthy football players (3.19/AE) (Huber et al., 2021). It means that visual impairment may increase head impact frequency. Impacts to the back of the head have been reported to be more likely to cause concussion than other areas (Brennan et al., 2017). Furthermore, the losing team had a higher frequency of head impact in the penalty area and of head impact intense enough to cause falls, suggesting that the competition level is related with occurrence of dangerous head impact.

Implications: This is the first study examining the head impact characteristics during blind football game. These results would be useful information for athletes to prevent head injuries.

Funding acknowledgements: We have no funding acknowledgement in this study.

Keywords:
Blind football
Paralympic game
Head impact

Topics:
Sport & sports injuries

Did this work require ethics approval? Yes

Institution: Graduate school of Biomedical and Health Sciences, Hiroshima University

Committee: Ethical Committee for Epidemiology of Hiroshima University

Ethics number: E-1459