The Effect Corrective Exercise With and Without Visual Feedback on Lower Extremity Biomechanics and Dynamic Balance in Adolescent Female Athletes With Dynamic Knee Valgus: A Pilot Study

This study aimed to compare the effectiveness of corrective-plyometric training with and without visual feedback on landing biomechanics and dynamic balance in adolescent female athletes with dynamic knee valgus (DKV).

A total of 26 adolescent female athletes were randomly divided into feedback (n=10), exercise (n=8), and control (n=8) groups. Six weeks of training with and without visual feedback were prescribed for feedback and exercise groups, respectively. Biomechanical data were measured at initial contact (IC) and maximum knee flexion (MAX) using 8 motion analysis cameras (Vicon) and a Kistler force plate. Y-balance test was employed to evaluate dynamic balance.

Based on the between-group outcomes, knee flexion-extension moment at IC (P=0.026), hip internal rotation angle at IC (P=0.016), and MAX (P=0.028) significantly changed during double-leg landing. Ankle dorsiflexion angle (P=0.05), tibial external rotation angle (P=0.012), and anterior-posterior ground reaction force (P=0.05) at IC, maximum tibial external rotation angle between IC to MAX (P=0.042), and hip internal rotation angle at MAX (P=0.022) significantly changed during single-leg landing test. Y-balance significant improvements were recorded in anterior (P=0.000), posteromedial directions (P=0.000), and composite (P=0.023).

Corrective-plyometric exercises without visual feedback effectively improve landing biomechanics and dynamic balance in adolescent female athletes with DKV.