Epidemiology of injuries in juniors participating in top-level karate competition: a prospective cohort study.

BACKGROUND: Karate is a popular combat semi-contact sport among juniors, but there are only few studies available on the epidemiology of injuries in karate junior athletes. AIM: The aims of this study were to determine the incidence and pattern of injuries in top-level karate competition for athletes aged 16 to 20 years, and to compare injury rates between age groups (ie, under 18-year-old [U18] and under 21-year-old [U21]) and genders, following the introduction of new weight categories.
METHODS: A prospective injury surveillance was undertaken at four consecutive World Karate Championships (2009 to 2015), following the same protocols used in previous investigations.
RESULTS: During the four championships, a total of 257 injuries were recorded, with an incidence of 41.4/1,000 athlete exposures (AEs, 95% CI 36.4 to 46.3). The injury rate was significantly lower for females with a rate ratio 0.63 (95% CI 0.48 to 0.82). Most of the injuries were minor ones: contusions (n=100), followed by abrasions (n=63) and epistaxis (n=62). Only 10% of the injuries were time-loss injuries (injury incidence rates 4.2/1,000 AEs; 95% CI 2.7 to 6.1). Face injuries represented 69.6% of the injuries, most of them were minor ones (light abrasions 24.5%, epistaxis 24.1%, contusion 16.7%). Change of rules (raising the number of weight categories from three to five) reduced injury incidence in the U21 category.
CONCLUSIONS: The total injury rate in junior competitions is lower compared with elite adult athletes and higher compared with younger elite athletes. Time-loss injuries are rare. The implementation of the new competition categories in U21 karate has been associated with a significant reduction in injury rate. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.