Fig. 4

Early swing discrete summary metrics: Lower-limb dynamics. These plots highlight the differences in lower-limb motion between transfemoral prosthesis user falls versus recoveries, with healthy control recovery data included as a reference. Peak thigh and knee flexion in the ipsilateral (tripped/sound-side) step were calculated from perturbation to first ipsilateral foot-strike. Peak thigh flexion in contralateral (prosthetic-side) step was calculated from first ipsilateral foot-strike to first contralateral foot-strike or fall, whichever index occurred first. An “x” in a marker indicates the prosthesis user did not foot-off prior to falling. Capital letters above each plot correspond to letters that are marked in Fig.  3 for reference