Investigating the landing kinetics factors and preparatory knee muscle activation in female handball players with and without dynamic knee valgus while performing single leg landing

Abstract Study aim: to examine the differences in landing kinetics factors (LKF) to assess the whole body stability and preparatory muscle activation (PMA) in female handball players with and without dynamic knee valgus. Material and methods: Twenty-four professional female handball players (11 with (DKV) and 13 without (Control) dynamic knee valgus) were asked to perform three trials of a single-leg landing. LKF and surface EMG were recorded. Initial contact knee valgus angle (IC KVA), vertical ground reaction force (vGRF), confidence ellipse area of center of pressure (CEA), time to stability (TTS) and EMG from 100 ms prior to ground contact were used in the data analyses. Results: Multivariate analyzing of LKF showed significant differences between two groups (p = 0.001) while for PMA the result was not significant (p = 0.361). Conclusion: Altered landing mechanism considered as a predictor of non-contact knee injuries such as ACL rupture. Therefore according to current study it seems important to focus on reducing valgus angle in designing injury prevention program.