Subtalar Joint Axis Rotational and Translational Motions During Closed Kinetic Chain Pronation and Supination In this three dimensional animation of the posterior, medial and dorsal view of the weightbearing foot skeleton during closed kinetic chain subtalar joint (STJ) pronation and supination, the STJ axis is noted to undergo significant internal rotation, plantarflexion and medial translation during during pronation. In addition, during STJ supination, the STJ axis undergoes external rotation