Participation in high school girls’ lacrosse is increasing, commensurate with concerns of risks for head impacts. Wearable sensors coupled with video analysis have characterized the incidence of head impacts in girls’ lacrosse. However, due to high sensor measurement error, the true incidence of game-related impacts remains unclear.
Purpose: Characterize the incidence of impacts in girls’ high school lacrosse using video analysis.
Methods: Forty participants volunteered in 16 games during the 2019 lacrosse season. All games were filmed using a digital camera affixed to a tripod to capture impacts. Descriptive statistics were reported for all video-identified game-related impacts (VIGI), including impact rates (IR) and 95% confidence intervals (CI).
Results: There were 208 VIGI, for 297 player-games (IR=.70 impacts/player-game, CI: 0.61, 0.80). Overall, midfielders had the most impacts (n=88, 42.3%) followed by attackers (n=79, 38%) and defenders (n=41, 19.7%). The most common impact mechanisms were player (n=105, 50.5%), stick (n=88, 42.3%), and ground (n=13, 6.3%) contact. Most impacts occurred during offense-defense transitions (n=44, 21.2%) and settled game play (n=39, 18.8%), defending (n=33, 15.9%) and shooting (n= 34, 16.3%). Of all impacts, 29 (13.9%) were direct head impacts (IR=.10, CI: 0.06, 0.13). The most common head impact mechanisms were contact with stick (n=24, 82.8%), ground (n=4, 13.8%), and ball (n=1, 3.4%). The most common game play impact characteristics were shooting (n=7, 24.1%), settled game play (n=7, 24.1%), offense-defense transitions (n=4, 13.8%) and defending (n=4, 13.8%). A penalty was called by the referee for 17 (58.6%) head impacts.
Conclusion: The incidence of overall VIGI was considerably greater than previously reported studies using a sensor driven approach to identify and subsequently verify impacts using video. However, the rate of head impacts was lower, but similarly stick and ground contact remained the most common mechanisms despite their prohibition in the sport. Our findings reinforce the need for rule enforcement of prohibited game play behaviors. Prospective video analysis of head impacts in girls’ lacrosse may assist with characterizing impacts and their incidence, especially as the sport shifts toward the intervention of headgear.