The common mechanisms of anterior cruciate ligament injuries in judo: a retrospective analysis.

Background: Although high prevalence of anterior cruciate ligament injuries (ACL) in judokas has been reported, there has been very little research concerning events preceding the injury.

Objective: To determine the common situations and mechanisms of ACL injury in judo.

Methods: A total of 43 cases of ACL injuries that had occurred during judo competition or practice were investigated, using questionnaires with interviews conducted by a single certified athletic trainer who has 20 years of judo experience to obtain information regarding the situation and mechanism in which the ACL injury occurred.

Results: The number of ACL injuries when the participant's grip style was different from the style of the opponent (ie, kenka-yotsu style) (28 cases) was significantly greater than when the participant's grip style was the same as that of the opponent (ie, ai-yotsu style) (15 cases; p<0.001). The number of ACL injuries was significantly higher when the participant 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 ACL injury incidence among the participants (16.8%).

Conclusions: Grip style may be associated with ACL injury occurrence in judo. In addition, direct contact due to the opponent's attack may be a common mechanism for ACL injuries in judo.