A patient who has worn down the lateral side of their shoe's heel and sole likely exhibits which foot function?

Wearing down the lateral side of a shoe's heel and sole typically indicates that the patient is exhibiting rear foot varus. This condition occurs when the hindfoot is inverted, leading the person to bear weight more on the lateral aspect of the foot during walking or running. As a result, the lateral side of the shoe experiences more wear than the medial side, manifesting as an uneven wear pattern.

In a situation of rear foot varus, the foot alignment causes compensatory mechanisms in the gait, imparting increased stress on the lateral aspects of the footwear. This pattern of wear is indicative of the alignment of the foot and how it interacts with the ground during various activities, confirming that the foot’s orientation plays a significant role in the wear patterns of footwear.

The other options each describe different positions or conditions of the foot, which would lead to different wear patterns on shoes, but none would result in the specific wear pattern seen in this case.