842 FO10 – The incidence and proportion of head acceleration events (HAEs) >20g in Professional women’s rugby union matches using instrumented mouthguards (iMGs)

Background Concussion is the most common injury in women's rugby union, although limited research has investigated head acceleration events (HAEs) using instrumented mouthguards (iMGs). Objective Describe and compare the incidence of HAEs and the proportion of tackles and carries resulting in HAEs in elite level women's rugby union using iMGs and video analysis. Design Prospective cohort. Setting Professional rugby players from one women's competition (Farah Palmer Cup). Participants Ninety-three professional female rugby union players across 643 player-matches. Main Outcome Measurements Incidence rates were calculated as the number of HAEs (as recorded by iMGs) per player-hour. Proportions were calculated as the percentage of tackles and ball-carries resulting in an HAE. Values are reported across a range of peak linear acceleration thresholds with 95% confidence intervals (CI) for the Poisson distribution. Results The incidence (CI) of HAEs per player-hour for forwards vs backs was 2.18 (0.00–5.00) vs 1.75 (0.00–5.00) between 20–40g (p=0.002), 0.22 (0.00–1.00) vs 0.26 (0.00–2.00) between 40–60g (p<0.001), and 0.04 (0.00–1.00) vs 0.05 (0.00–1.00) >60g (p=0.747). The proportion (CI) for tackles vs ball-carries to result in a HAE was 10.29% (5.00–17.00%) vs 8.56% (3.00–15.00%) for HAE >20g (p=0.022), 1.36% (0.00–4.00%) vs 1.26% (0.00–4.00%) for HAE >40g (p=0.733) and 0.22% (0.00–1.00%) vs 0.23% (0.00–1.00%) for HAE >60g (p=0.934). Conclusions Forwards experienced a significantly higher rate of HAEs across a range of PLA magnitudes. A small proportion of tackles and ball-carries result in a HAE >20g, which can be used to identify and reduce high magnitude events.