Distribution of plantar pressure on the second metatarsal head during walking.

BACKGROUND AND PURPOSE Although high pressure occurs on the second metatarsal head during waking, the distribution of this plantar pressure has not been reported. The purpose of the study was to analyze the distribution of plantar pressure on the second to the fourth metatarsal heads during walking in healthy adults. METHODS Plantar pressure was measured at the second and adjacent metatarsal heads by 2.54 mm x 2.54 mm transducers during walking in 72 healthy adults (32 women and 40 men). Data at the instant of peak pressure were analyzed using spatial statistics. The length and width of 90% predicted peak pressure (PPP), and anterior and posterior extents to 80, 70, 60, and 50% PPP were regressed by peak pressure, body height, body weight, gender, and foot length of the subjects. RESULTS The distribution parameters of plantar pressure decreased proportionally from the second to the fourth metatarsal heads, and were different from the first metatarsal head. The distribution parameters were inversely correlated to peak pressure. Besides peak pressure, the length and width of 90% PPP, and anterior extent to 80% PPP could be predicted by body weight. The anterior extent to 70% PPP could be predicted by foot length. The posterior extent to 80, 70, 60, and 50% PPP could be predicted by body height of the subjects. CONCLUSIONS Besides peak pressure, the distribution of plantar pressure was correlated with body weight, body height, and foot length at different areas on the second metatarsal head in normal adults.