Article

When taking molds for foot orthoses, it is accepted practice to position the
subtalar joint in its neutral position. However, foot orthoses have no contact
with the talus, and this leads to a hypothesis that as long as there is
correction available to appropriately align the forefoot relative to the hindfoot
when taking a mold, changes in subtalar joint angles do not lead to significant
alterations in the plantar surface shapes of the molds taken. This study tested
this presumption with 20 subjects between 22 and 46 years old. During
non-weight-bearing casting, the subtalar joints were aligned at positions of 4
degrees of eversion, 2 degrees of eversion, 2 degrees of inversion, and in
neutral. At each orientation, forces were applied over the forefoot such that the
metatarsal heads were aligned with the rearfoot. Digital scanning was used to
analyze the shape of each negative mold. There were significant changes in
projection volume in different subtalar joint orientations. However, the changes
in arch heights, navicular height, and protrusion were insignificant and very
small. It is therefore suggested that as long as the forefoot and hindfoot are
appropriately aligned, variations in the orientation of the subtalar joint would
be acceptable.

Langue : ANGLAIS