Figure 1

Diagram of the three modifications to the foot protocol. A) Definitions of the four rigid segments according to relevant anatomical landmarks (full list in Leardini et al. [10]). X and Z axes (solid arrows) of the anatomical reference frames are shown together with corresponding transverse planes (dash-dot triangles), including the new one for the Phalanx. B) Definition of the improved frontal-plane angle of the calcaneus with respect to the shank, according to the position of the additional marker HL. C) Scheme for the calculation of the planar MLA angle in the sagittal plane of the foot, where CAp is the projection of the CA marker on the ground.