Figure 6

Right (R) and left (L) hip extension, knee flexion, thigh extension and trunk orientation angles at take-off for the data-tracking (T) and predictive simulations (A-free, K-free, H-free, A-K-free, H-K-free, H-A-free, A-K-H-free). Full knee extension = 0° and knee flexion is negative; thigh aligned vertically with pelvis corresponds to hip flexion–extension = 0°, and hip flexion is positive and hip extension is negative. Thigh and trunk segment angles are defined relative to the vertical axis of the global coordinate system. Negative thigh and trunk segment angles (clockwise rotations) correspond to extension and forward inclination, respectively. These are consistent with the model’s definitions.