Article Text
Abstract
Background Studies investigating biomechanical risk factors for knee injuries in sport specific tasks are needed.
Objective To investigate association between change of direction (COD) biomechanics and knee injury risk among youth team sports.
Design Prospective cohort study.
Setting Youth basketball and floorball.
Participants 258 female and male players (aged 12–21).
Assessment of Risk Factors COD biomechanics were analysed using 3D-motion analysis. The COD test consisted of a quick ball pass before and after a high-speed 180° pivot turn on the force plates.
Following variables were analysed
Peak vertical ground reaction force (N/kg), peak trunk lateral flexion angle (degree), peak knee flexion angle (degree), peak knee valgus angle (degree), peak knee flexion moment (Nm/kg), peak knee abduction moment (Nm/kg), and peak knee internal and external rotation moments (Nm/kg). Mean of three trials was used. Injuries and exposure were registered for 12 months.
Main Outcome Measurements New acute non-contact knee injury.
Results The complete data was obtained from 109 female and 149 male basketball (n=130) and floorball (n=128) players. A total of 18 new non-contact knee injuries were registered (0.3 injuries/1000 h of exposure). Female players sustained 14 knee injuries and male players 4. A higher rate of knee injuries was observed in females compared with males (incidence rate ratio 6.2, 95% CI 2.1–21.7). Eight ACL injuries were registered (all in female players). Females displayed significantly larger peak knee valgus angles compared with male (mean for female and male, respectively: 13.9 and 2.0 degree). No significant associations between biomechanical variables and knee injury risk were found.
Conclusions Female players were at increased risk of knee and ACL injury compared with males. Female players performed the 180-degree pivot turn with significantly larger knee valgus compared with male. However, none of the investigated variables were associated with knee injury risk in youth basketball and floorball players.