Head impact exposure from match participation in women’s rugby league over one season of domestic competition

Abstract Objectives: To quantify the magnitude, frequency, duration and distribution of head impact exposure in a women’s rugby league competition. Design: Prospective cohort study. Methods: Twenty-one players had a wireless impact measuring device (X2Biosystems XPatch) behind their right ear during match participation. Head impact data were collected and downloaded for analysis. Median peak linear and rotational accelerations and impact locations between player positions were assessed using a Friedman repeated measures ANOVA on ranks with a Wilcoxon signed-rank test for post hoc analysis with a Bonferroni correction. Results: A total of 1,659 impacts to the head >10g were recorded (range 10g to 91g) over the nine competition matches. There was a mean of 184 ±18 impacts per-match resulting in a mean of 14 ±12 impacts per-player per-match. The No. 8 prop recorded a mean of 29 ±27 impacts per-match, the No. 12 second-row forward recorded the highest median peak resultant linear acceleration (16g) per-match and the No. 11 second-row forward recorded the highest median peak resultant rotational acceleration (3,696 rad/s2). Conclusion: Our cohort of 21 female rugby league athletes were exposed to repetitive sub-concussive head impact exposure with an average of 14 impacts per-player per-match. Forwards were exposed to more impacts per-match than backs and these impacts were of higher magnitude. Most impacts occurred on the side of the head and were sustained during the second half of the game. Clinicians, coaches and players should be aware of the rates and magnitude of head impacts in female rugby league athletes. Keywords: Head impact; rugby league; peak linear acceleration; peak rotational acceleration