comparison of knee kinematic factors between ball and rocket athletes in predictable and unpredictable cutting maneuvers

Purpose: anterior cruciate ligament injury is one of the most severe knee injuries that often has a non-contact mechanism and follows an incorrect knee joint alignment. the present study aimed to compare the effect of predictable and unpredictable cutting direction on knee joint kinematics in ball and racket athletes. methods: the present study was quasi-experimental, and the subjects included 48 female adolescent athletes from badminton (n=12), table tennis (n=12), basketball (n=12), and handball (n=12). after the initial evaluations, the cutting maneuver was performed in predictable and unpredictable ways and recorded by a three-dimension motion analysis. also, 1-way anova and post hoc tests were used to compare the kinematic parameters of the knee between the ball and racket athletes. results: the results of the statistical test showed a significant difference in the kinematic parameters of knee flexion (p=0.003), knee valgus (p=0.001), and tibia rotation (p=0.001) between the ball (basketball and handball) and racket athletes (badminton and table tennis) in the predictable cutting. but in the unpredictable cutting, there were no significant differences in the kinematic parameters of the knee flexion (p=0.86), knee valgus (p=0.56), and tibia rotation (p=0.18). conclusion: the results indicated that ball athletes showed an increased kinematic risk factor such as decreased knee flexion, increased knee valgus, and tibia rotation more than rocket athletes. therefore, injury prevention programs are more critical in ball athletes.