A total of 31,655 tackles in 48 professional rugby league matches were coded from video for height and direction of tackle on the ball carrier. Injuries were recorded by team medical staff for injury date, time, site, type, mechanism, severity, and player position. Tackle-related injuries were most frequently the result of two tacklers being involved in tackling the ball carrier from the side at shoulder or midtorso body levels. The ball carrier had a higher injury rate when tackled from behind his visual field at shoulder height and in the fourth quarter of matches. Tacklers had a higher risk of injury when tackling from the side of the ball carrier, as the first tackler, and in the third quarter of matches. Coaches should focus on practicing correct technique during tackling with two or more tacklers and when tackling in the ball carrier's blind vision area.
OBJECTIVEDirect impact with the head and the inertial loading of the head have been postulated as major mechanisms of head-related injuries, such as concussion.METHODSThis descriptive observational study was conducted to quantify the head impact acceleration characteristics in under-9-year-old junior rugby union players in New Zealand. The impact magnitude, frequency, and location were collected with a wireless head impact sensor that was worn by 14 junior rugby players who participated in 4 matches.RESULTSA total of 721 impacts > 10g were recorded. The median (interquartile range [IQR]) number of impacts per player was 46 (IQR 37–58), resulting in 10 (IQR 4–18) impacts to the head per player per match. The median impact magnitudes recorded were 15g (IQR 12g–21g) for linear acceleration and 2296 rad/sec2 (IQR 1352–4152 rad/sec2) for rotational acceleration.CONCLUSIONSThere were 121 impacts (16.8%) above the rotational injury risk limit and 1 (0.1%) impact above the linear injury risk limit. The acceleration magnitude and number of head impacts in junior rugby union players were higher than those previously reported in similar age-group sports participants. The median linear acceleration for the under-9-year-old rugby players were similar to 7- to 8-year-old American football players, but lower than 9- to 12-year-old youth American football players. The median rotational accelerations measured were higher than the median and 95th percentiles in youth, high school, and collegiate American football players.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.