We describe the characteristics of the medial longitudinal arch (MLA) of th
e right foot in 19 healthy men while sitting/partial bodyweight, standing/f
ull bodyweight, and during the stance phase of walking. Three measurements
were selected as representative of the MLA, including: height of the arch,
length of the arch, and supranavicular angle. Mean Values were calculated i
n three dimensions for each measure in the sitting and standing conditions
and for the minimum value of each measure in the walking condition. Pattern
s measured during walking had high association (r = 0.999) and could be rel
ated to phases of stance. In the stationary conditions, the MLA varied sign
ificantly (P < 0.001). No significant relationship of arch height, arch len
gth, or supranavicular angle was found between sitting and standing or betw
een stationary and walking conditions. It was concluded that none of the st
atic variables could be used to predict others and that static measures of
the MLA do not predict the dynamic motion of the MLA. The MLA may not be a
reasonable indicator of behavior or motion of the foot.