Pronation Part II – What is pronation II

Pronation and flat feet are often confused because many pronators have collapsed arches when weight bearing. In other words, when people stand and pronate, their arches often flatten out, which can be misinterpreted as “flat feet.” Before we discuss the difference between the two, we must first discuss the subtalar neutral position of the ankle, and forefoot varus.

When a foot is placed in subtalar neutral, the axis of the tibia, talus, and calcaneus are in line and perpendicular to the ground. In this position, the ankle is neither pronated nor supinated. Once the foot is placed in subtalar neutral, the person’s inherent anatomical structure of the bones determines where the rest of the foot falls. More often than not, when patients are placed in subtalar neutral, the ball of the foot is elevated off the ground (forefoot varus*), as seen in the video. Once that happens, in order to stand and bear weight, the ball of the foot must come down. This is the reason why most people pronate! When the ball of the foot comes down, pronation occurs as the midfoot rotates medially (inward).

Since the degree of pronation is based on how far the ball of the foot comes off the ground when the ankle is put in subtalar neutral (i.e., how far the ball of the foot must come down to reach the ground), people with varying arch heights can still pronate. On the other hand, someone could have anything between high or low arches but not pronate at all. It all depends on where the rest of the foot falls after the ankle is placed into a subtalar neutral position.

*Forefoot varus is an angled position of the bones in the forefoot when compared to the heel, where the bones on the inside of the forefoot rest higher than those on an outside, resulting in an oblique angle.

Key takeaway:

• Pronation is not the same as flat feet! It all depends on where your foot naturally positions itself once subtalar neutral is achieved.