Relationship between Hip and Knee Strength and Knee Valgus Angle during Drop Jump in Elite Female Athletes

Purpose: The purpose of this study was to investigate the relationship between hip and knee strength with knee valgus angle during drop jump in elite female athletes. Methods: Forty female athletes (mean ± SD age, 21.5 ± 1.99 years; height, 169.08 ± 8.25 cm; body mass, 61.05 ± 10.06 kg) participated in this study. Isometric hip and knee muscles strength were evaluated using standard clinical procedures and a handheld dynamometer. Knee valgus angle was assessed using a 6-camera motion analysis system during a drop jump task. Pearson correlation analyses were performed to determine the relationship between hip and knee muscles strength and knee valgus angle at initial contact (P≤0.05). Results: Hip abductor strength and knee flexor-extensor ratio were found to be negatively correlated with knee valgus angle (r = –0.229, P = 0.04 and r = –0.446, P = 0.002, respectively). Conclusion: No relationship between measure of hip external rotation strength and knee valgus angle was observed (P = 0.39). Strength training of the hip and knee musculature may still need to be addressed in prevention programs, but it also should be combined with teaching proper