Relationships between Foot Type and Dynamic Rearfoot Frontal Plane Motion
Foot posture has been implicated in
biomechanical dysfunction of the lower limb
and a variety of overuse injuries [1-3] . Many static
measures have been developed to describe
foot posture and subsequently investigated
as possible predictors of dynamic rearfoot
motion [4,5] . Measures have included frontal
plane calcaneal angle, (frequently referred to
as rearfoot angle), medial arch angle and arch
height, however, none has consistently been
found to be accurate predictors of dynamic
rearfoot motion for stance phase [4-8] . The
clinical and research benefits of having an
a continuum relative to pes planus or cavus
position and the ease of application of the
model.
Measurement of the rearfoot includes a
combination of transverse and frontal plane
assessments including talar head palpation,
curvature above and below the malleolus and
frontal plane position of the calcaneus. The
forefoot measurements combine transverse
and sagittal plane measurements including
prominence of a talonavicular bulge, forefoot
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Pedorthic Footcare Association | www.pedorthics.org
easily performed static measurement capable
of predicting dynamic function are significant,
potentially assisting in improved accuracy of
clinical screening and orthotic prescription,
and standardization of functional foot type for
research.
The six item Foot Posture Index, (FPI), uses
a validated criterion-based observational
measurement of the forefoot and rearfoot in a
static position [9] . The reference system differs
from previously described classification systems
due to the number of observations recorded,
the inclusion of multi-segment and multiplanar
measurements evaluating foot position on
transverse plane position and sagittal plane
congruence of the medial longitudinal arch.
A score is allocated to each measure to give
a total overall score indicative of foot posture
with reference values provided for classification
purposes [9] .
Previous research assessing the capacity of the
FPI to predict dynamic function has assessed
three-dimensional inversion/eversion of the
ankle joint complex during the midstance of
walking and midfoot motion measured via
@Shutterstock.com/Maridav
Background