Clinical biomechanics of the peritalar joint.

The peritalar joint includes the articulations between the talus and calcaneus and the talus and navicular. Motion between the talus and calcaneus is described most often as rotation about an axis that points medially, anteriorly, and superiorly. This motion is considered to be triplanar, with inversion, plantar flexion, and adduction occurring together, whereas eversion, dorsiflexion, and abduction are associated. Similar motions have been described between the talus and navicular. Foot deformity, such as a pes planus or a pes cavus foot type, and hindfoot or midfoot joint fusion can alter the biomechanics of the peritalar joint.