Influence of sensory input on plantar pressure distribution

The sensory feedback control system plays a central role in human locomotion. However, few studies have been published discussing the influence of sensory input at the plantar surface of the foot on the kinematics and kinetics of locomotion. The purpose of this study was to examine the effect of changes in sensory input at the plantar surface of the foot on the pressure distribution measured at the plantar surface of the foot. Three pairs of specially made socks with sand at the plantar surface of the foot and one pair of normal socks were used to simulate different sensory inputs. Pressure distribution at the plantar surface of the foot was measured using an emed system for 10 subjects for each of the four sensory input conditions during walking and running on a treadmill. The results showed significant and substantial changes in pressure in selected areas for changes in sensory input. The pressure increased in the midfoot area and decreased in the toe area with increasing sensory inputs. These results are similar to results of a previous study where similar changes were found in a comparison between comfortable and uncomfortable shoes. RELEVANCE: Pressure distribution is increasingly used in clinical assessments. However, the factors influencing the pressure distribution pattern are only partially understood. One factor may be the sensory input into the foot. It is important to understand this influence in order to provide appropriate interpretation of the pressure distribution data.