Rotational equilibrium across the subtalar joint axis

A review of the rotational forces, or moments, acting across the subtalar joint axis during relaxed bipedal stance is presented. The concept of rotational equilibrium about the subtalar joint axis is used to explain some of the biomechanical differences between feet that stand in the neutral and maximally pronated subtalar joint positions. In addition, the mechanical basis of treatment of sinus tarsi syndrome with foot orthoses using the concepts of subtalar joint axis moments rotational equilibrium of the subtalar joint is presented.