FOOT PRESSURE DISTRIBUTION DURING WALKING AND SHUFFLING

The insensate foot is vulnerable to tissue damage from areas of repetitive, excessive pressures. It has been previously stated that a shuffling gait with short steps would increase the period of foot flat and thus minimize any excessive local plantar pressures. This theory was quantitatively evaluated with a portable, in-shoe pressure data-acquisition system. Seven pressure sensors were located in the left and right insoles under the metatarsal heads, hallux, and posterior and anterior heels. Plantar pressure data were acquired from ten able-bodied subjects during four minutes of continuous shuffling and walking at a metronome-controlled cadence. Peak pressures, foot-to-floor contact durations, and pressure-time integrals under each sensor during shuffling and walking were analyzed and compared. Peak pressures were decreased at all sensor sites during a shuffling gait. The greatest decreases were noted at the first and second metatarsals (up to 57.8%) and hallux (up to 63.2%). A 41.6% decrease in overall summated peak plantar pressures during shuffling was found. Foot-to-floor contact durations during shuffling were increased from 22.0% to 76.9% at all 14 sensor locations. Pressure-time integrals during shuffling were increased at the heels (up to 78.9%) and decreased at the metatarsal heads and great toes (up to 26.7%). There was a 3.3% increase in the overall summated pressure-time integral during shuffling. Our findings are consistent with the hypothesis that a shuffling gait increases the period of foot flat and the area of weight bearing, resulting in lower peak plantar pressures on any one area.