Shape Approximation and Size Difference of the Upper Part of the Talus: Implication for Implant Design of the Talar Component for Total Ankle Replacement

Figure 3

Establishment of the coordinate system ((a) front view and (b) top view of three-dimensional (3D) illustration) and geometry parameters of the talar trochlea ((c) front view and (c) top view of two-dimensional (2D) illustration. Parameters included the radius of the lateral sphere (), the radius of the medial sphere (), the distance between sphere origins (), the height () of the plane , the position of planes and ( and ), and the angles between the fitting planes to the horizontal or sagittal plane (, , , and )).

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