A kinematic model of the human ankle.
The spatial gross motion of the foot with respect to the shank is modelled as rotations about two fixed ankle axes: the upper ankle rotation axis (plantar flexion/dorsiflexion) and the subtalar rotation axis (inversion/eversion). The positions of the axes are determined by externally visible bony landmarks of the lower leg, and are measured for a living subject. The model input data are the plantar flexion/dorsiflexion and inversion/eversion rotation angles; the model output is a 4 X 4 transformation matrix which quantitatively describes the relative position of a foot coordinate system with respect to a shank coordinate system.
D000843:Ankle Joint / Q000502:physiology*; D006801:Humans; D008433:Mathematics; D008954:Models, Biological; D009068:Movement; D012399:Rotation