Pronation and Supination

Throughout the Gait Cycle, as the foot alternates between a mobile adapter and a rigid lever, it does so using the motions of pronation and supination respectively.

These motions are created within the Sub-Talar Joint; the joint formed between the upper surface of the Calcaneus (heel bone) and the underside of the Talus (keystone of the Medial Longditudinal Arch).

The motions are created by the combination of movement in three planes, as shown in the diagrams below. They are opposing motions and cannot occur together.

You can feel these movements by doing the following:

• Stand without shoes with feet approximately hip width apart;
• Keeping the length of your foot in contact with the ground roll your feet inward, so that the ankles get closer together and the medial arch lowers – This action is the motion of Pronation;
• Still keeping the base of your foot in contact with the ground, roll yout feet back to where you started, and then roll outward, in the opposite direction. You will feel as through you are standing on the outside of your feet. This action is the motion of Supination.