Sex Differences In Head Injuries Among Collegiate Soccer Players

Abstract

Some of the highest rates of head injuries and concussion among all contact/collision sports are observed in soccer; yet, the multifactorial determinants of head injuries among players remain relatively undefined. PURPOSE: To examine sex-differences in the rate and the severity (lost days of participation, resultant concussions) of head injuries among collegiate soccer players between 2004 and 2009, while controlling for several covariables previously linked to injury occurrence. METHODS: Data from the National Collegiate Athletic Association Injury Surveillance System (NCAA-ISS) were used to calculate injury incidence density (ID) per 1000 athletic exposures (AE). The rate ratio (RR), along with the 95% Wald confidence interval (CI), compared ID among female, relative to male soccer players. Multivariable logistic regression and multivariable negative binomial regression modeling then tested the relation between sex and head injury incidence and severity while controlling for contact, setting, and competition level. RESULTS: Between 2004 and 2009, the sex-specific rate of soccer-related head injuries was 0.87 per 1000 AEs in women and 0.71 per 1000 AEs in men (RR = 1.23, 95% CI = [1.08, 1.41]). The rate of head injuries due to player-to-player contact was comparable between women and men (RR=0.95, 95% CI=[0.81, 1.11]); however, the rate of injury due to contact with apparatus was nearly 2 ½ -fold higher (RR=2.46, 95% CI = [1.76, 3.44]) and the rate due to contact with a playing surface was over two-fold higher (RR=2.29, 95% CI = [1.34, 3.91]) in women than in men. We also observed a significant joint effect between sex and contact in our regression models, with a particularly notable antagonistic interaction observed while modeling head injuries. CONCLUSION: Among female players, head contact with a ball, a goal post, or the playing surface may be especially deleterious compared with head contact with another player.