Frontal plane take-off step mechanics of long jumpers with and without a below the knee amputation

Frontal plane mechanics during the long jump take-off step are unknown for athletes with and without a transtibial amputation. This is an issue due to the importance of the knowledge for training and rehabilitation protocols or prosthetic design. In this study the take-off step of three long jumpers with and seven without a below the knee amputation (BKA) were analysed with regard to frontal plane mechanics. Three-dimensional motion capture (Vicon) and a force plate (Kistler) were used to capture kinematic and kinetic data. Inverse dynamic calculations (Dynamicus, Alaska) revealed differences in frontal plane center of mass kinematics and joint kinetics between groups. Specifically, athletes with BKA had lower medio-lateral ground reaction forces, lower frontal plane joint loads and an altered foot position pattern compared to non-amputee athletes.