Relationships between clinical measures of static foot posture and plantar pressure during static standing and walking.

BACKGROUND: Information is limited about the relationships between clinical measures of static foot posture and peak plantar pressures under the medial column of the foot. The purpose was to examine these relationships during static standing and walking.

METHODS: A single-group exploratory design using correlation and regression was used to determine relationships. Ninety-two healthy volunteers participated. Clinical measures of static foot posture including arch index, navicular drop and navicular drift were obtained during static standing. Peak plantar pressures under the hallux, medial forefoot, medial midfoot, and medial rearfoot were obtained during standing and walking.

FINDINGS: Static foot posture was related to peak plantar pressures during standing and walking, but the strengths of relationships ranged from poor to fair. During standing, navicular drop was correlated (P≤0.05) with hallux (r=0.29) and medial forefoot (r=-0.17) pressures, while arch index (r=-0.17) and navicular drift (r=0.25) were correlated (P≤0.05) with hallux pressure. During walking, arch index, navicular drop and navicular drift were correlated (P≤0.05) with hallux and medial forefoot pressures (r range -0.30 to 0.41), while arch index (r=-0.15) and navicular drop (r=0.16) were correlated (P≤0.05) with medial midfoot pressure. Regression models predicted (P≤0.05) hallux (R(2)=0.08) and medial midfoot (R(2)=0.05) pressures during standing, and hallux (R(2)=0.18), medial forefoot (R(2)=0.07), and medial rearfoot (R(2)=0.05) pressures during walking.

INTERPRETATION: In healthy participants, lower arch foot postures are associated with greater pressures under the hallux and medial mid-foot and lower pressures under the medial forefoot, but the strength of these relationships may be only poor to fair.