Dominant Vs Non Dominant Leg Differences In Jump Landing From Different Directions In Active Females

Side-to-side differences in jump landing may be associated with injury specifically single-leg landing on the dominant leg (DL) may have a higher risk of knee injury compared to the non-dominant leg (NL). Previous studies (Kernozek, 2005) have reported differences in knee valgus angle at peak vertical ground reaction forces (VGRF) with minimal data at the ankle joint. PURPOSE: To determine differences in the external knee joint valgus moment at peak VGRF and ankle joint angle at initial contact during jump landing in active women, between DL and NL. METHODS: Kinematic and kinetic data were collected on 8 athletic females for single-legged jumps from different directions (0°, 30°, 60°, 90°) for both DL and NL. Kinematic marker trajectories and ground reaction forces were collected using an 8-camera Vicon system and an AMTI force plate. RESULTS: There was a greater plantarflexion angle at landing on average in the NL compared to the DL at all angles. (Average differences: 0° = 2.5°, 30° = 3°, 60° = 3.3°, 90° = 2°). The difference in the frontal plane external knee moment (Nmm/kg) between the NL and DL ranged between a 12%-33% difference. 90° had the largest difference (NL: 37.3 Nmm/kg, DL: 101.3 Nmm/kg) CONCLUSIONS: A larger plantarflexion angle at contact in the NL may suggest a softer landing due to the potential increase in dorsiflexion range of motion during landing. Larger frontal plane knee moments (valgus/varus) were found at 90° with the DL having a larger moment. This finding contributes to a better understanding of the role of limb dominance during movement execution in active females and provides theoretical support for sports training and rehabilitation.