1st Joint ESMAC-GCMAS Meeting - Análise de Marcha

O-48
TRACKING DYNAMIC FOOT PRESSURE PATTERNS IN YOUNG CHILDREN
WITH SPASTIC CEREBRAL PALSY
Nancy Lennon, MS, PT, Scott Coleman, MS, Christopher Church, MPT, John Henley, PhD,
Theresa Angeli, MPT, Freeman Miller, MD.
The duPont Hospital for Children, Wilmington DE, 19805
Summary
A trend of improving foot valgus during the early stages of walking, similar to typical
development, is seen in children with cerebral palsy (CP). As they grow, children with CP
develop a wide variety of foot pressure patterns and do not follow trends seen in normal
development. Most patterns of foot varus or valgus that emerge at age 4 can be predicted from
physical exam and gait observational measures at age 2.
Introduction
The natural history of dynamic foot posture is not documented for children with cerebral palsy.
Our Gait Laboratory is collecting foot pressure data on a large sample of young children with
CP to provide this information. During the first year of the study we reported that pes valgus is
present in newly walking children with CP and that this valgus tends to diminish over the first
several months of walking 1 . This early trend is similar to that seen in the foot pressure patterns
of typically developing children 1 . This ongoing research in the Gait Lab is expected to describe
the natural history of foot deformity in children with CP from the onset of walking through
adolescence.
Clinical Significance
Understanding the natural history of dynamic foot posture in children with CP will lead to
more appropriate interventions. Predicting which children will develop serious foot deformities
allows intervention at an early stage, prevents progression of deformities, and reduces the
surgical burden to the child.
Methods
A total of 72 children with CP have participated in our larger study to date. The current
analysis includes a subset of 16 children followed every 6 months for two years (+/- 4 months).
A brief physical exam was performed and a portion of the GMFM was administered
(dimension D) at each visit. Mean age at visit one was 31 months and at visit four was 51
months. Mean GMFM(dimension D) at visit one was 54% and at visit four was 67%. Dynamic
foot pressure measurements were collected at each visit using the F-Scan measurement system
(Boston, MA). A coronal plane pressure index (CPPI) was utilized to identify dynamic foot
valgus or varus pressure patterns during walking 2 . This measurement defines the ratio of
medial to lateral pressure impulses in the midfoot and forefoot regions. A trend analysis was
performed on the foot pressure data using CPPI across time as the variable of interest.
Multiple regression analysis was performed using CPPI at visit four as the outcome variable
and a group of 10 physical exam, gross motor, and simple gait measures from visit one as the
predictors (forefoot ab/adduction, spasticity, dorsiflexion, hip ER, GMFM, trans-malleolar
axis, popliteal angle, foot progression angle in gait, CPPI, and medial midfoot impulse
variability).
Results
Figure 1 displays the group mean CPPI at each visit. The initial reduction in valgus seen
between visits one and two is significant. The trend of diminishing valgus does not persist
across all four visits, as children begin to develop different pressure patterns of varus or valgus
with growth.
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