Numata H, et al. - The correlation between knee valgus angle and non-contact anterior cruciate ligament (ACL) injury in young female athletes was examined here, through the coronal-plane two-dimensional (2D) kinematic analyses of single-leg landing. It was concluded that dynamic knee valgus served as a potential risk factor for non-contact ACL injury in female high school athletes. A complete comprehension of the risk factors that increase dynamic knee valgus would aid in formulating a more appropriate training and interventional strategies to prevent injuries in at-risk athletes.

Methods

• The enrollment consisted of 291 female high school athletes newly recruited in basketball and handball clubs.
• An assessment was performed of the dynamic knee valgus during single-leg drop jumps via 2D coronal images at hallux–ground contact and at maximal knee valgus.
• Follow-up was for 3 years in the case of ACL injury.
• Twenty-eight (9.6%) of 291 athletes reported ACL rupture, including 27 non-contact ACL injuries.
• A comparison was pursued of the injured group of 27 knees with non-contact ACL injury with a control group of 27 randomly selected uninjured knees.
• The link between initial 2D movement analysis results and subsequent ACL injury was determined.

Results

• Dynamic knee valgus was found to be substantially greater in the injured group compared to the control group at hallux–ground contact (2.1 ± 2.4 vs. 0.4 ± 2.2 cm, P = 0.006) and at maximal knee valgus (8.3 ± 4.3 vs. 5.1 ± 4.1 cm, P = 0.007).