Friday, April 14th 3pm refreshments prior
003 CSB
Carl G. Mattacola, PhD, ATC
Associate Professor - Director
Division of Athletic Training
University of Kentucky
Title: Effect of Foot Orthotics on Star Excursion Balance Test Reach Distances in Subjects with
Chronic Ankle Instability
Objective: Our purpose was to determine the effects of four weeks of foot orthotic use on a
unilateral stance dynamic balance task in subjects with chronic ankle instability (CAI). Dynamic
postural control testing using the Star Excursion Balance Test (SEBT) has been used previously to
detect differences between healthy and CAI groups. Orthotic intervention following lateral ankle
sprain has demonstrated improvements in static postural control tasks. To our knowledge, there has
been no research investigating the effects of foot orthotic intervention in a CAI population. Design
and Setting: This study was a multiple test occasion repeated measures design. Eight 2 x 2 x 2
repeated measures ANOVAs were used to determine if differences exist. Independent variables
were limb (unstable, stable), week (1, and 4), condition (orthotic, no orthotic). Subjects: Twenty
subjects with self-reported CAI (24.15±7.73 years, 12 females, 8 males) were recruited from the
University of Kentucky general population. Measurements: Subjects reported for three test
occasions (1 familiarization session and two test sessions).
Orthotic fitting was completed at the first session and subjects wore orthotics for 4 weeks between
sessions 2 and 3. Six practice trials of the SEBT, and three test trials of the SEBT were completed
at each session. Subjects performed the test with and without orthotics during sessions 2 and 3 and
the order of testing was counterbalanced. SEBT reach distances in each direction and trial were
averaged and normalized as a percentage of each subject’s leg length. Results: A significant time
by orthotic interaction was observed in the posterolateral direction demonstrating that at time 2 the
orthotic condition was significantly higher than all other conditions. A time by limb by orthotic
interaction was observed in the medial direction demonstrating that at time 2, the unstable limb
with orthotic reach distances were significantly greater than all other instability conditions. A
significant main effect for the orthotic condition was demonstrated in all directions. Subjects were
able to reach a greater distance with orthotics than without.
Conclusion: Application of custom made semi-rigid foot orthotics resulted in improvements in
reach distance for the SEBT for both extremities in a CAI group. Likewise, orthotic intervention
resulted in improvements in the posterolateral, medial, and lateral directions when a semi-rigid
orthotic was employed for the unstable ankle. Orthotic intervention resulted in improved reach
distances for single limb assessment using the SEBT.