Background: Although high prevalence of anterior cruciate ligament injuries (ACL) in judokas has been reported, events preceding the injury have hardly been researched.
Objective: To determine the common situation and mechanism of the ACL injury in judo.
Methods: We investigated 43 cases of ACL injuries which had occurred during judo competition or practice. We used questionnaires with interviews conducted by one certified athletic trainer who has 20-year judo experience to obtain information regarding the situation and mechanism in which the ACL injury occurred.
Results: The number of the ACL injuries when the subject's grip style was different from the style of the opponent (i.e. kenka-yotsu style) (28 cases) was significantly greater than when the subject's grip style was the same as that of the opponent (i.e. ai-yotsu style)(15 cases)(P<0.001). The number of the ACL injury was significantly higher when the subject was attacked by the opponent than when counterattacked or when attempting the attack (P<0.001). In addition, being attacked with osoto-gari was revealed as the leading cause of the ACL injury incidence among the subjects (16.8%). Conclusions: Grip styles may be associated with the ACL injury occurrence in judo. In addition, direct contact due to the opponent's attack may be a common mechanism of the ACL injuries in judo.