what-when-how
In Depth Tutorials and Information
Figure 3.5
Heel eversion as a component of pronation
sustentaculum tali, rising up underneath the sustentaculum tali to directly
oppose eversion. The vertical peak in arch height should be close to the
talonavicular joint, which is highly mobile and a central feature of lowering
of the medial arch of the foot. The arch support should continue anteriorly
under the first metatarsal but cease proximal to the metatarsal head. This
ensures there is sufficient room for the first metatarsal to plantarflex as
the hallux dorsiflexes in late stance.
A less common but important consideration is the use of a lateral arch
support. Between the calcaneus and fifth metatarsal head there is a subtle
arch which is often neglected because it is far less visible than the more
obvious medial arch of the foot. To truly maximize contact with and
control of foot motion, however, all points of articulation should be
addressed. A rise in the orthosis between the plantar calcaneal tubercle
and the midshaft of the fifth metatarsal head will prevent the lateral arch
lowering. Since all rear- and midfoot movements are coupled, neglecting
this site can mean that good orthotic design features at the heel and
