Influence of foot type and orthotics on static and dynamic postural control

Context: The effects of custom-molded foot orthotics on neuromuscular processes are not clearly understood. Objective: To examine these effects on postural control in subjects with different foot types. Design: Between-groups, repeated-measures design. Setting: Athletic training laboratory. Subjects: 30 healthy subjects assigned to groups by foot type: planus (n = 11), rectus (n = 12), or cavus (n = 7). Interventions: Custom-fit semirigid orthotics. Main Outcome Measures: Static postural control was measured on a force plate. Dynamic postural control was measured using the Star Excursion Balance Test. Both measurements were assessed with and without orthotics at baseline and 2 weeks later. Results: For static postural control, a significant condition-by-group interaction was found. Subjects with cavus feet had a decreased center-of-pressure velocity while wearing orthotics. For dynamic postural control, a significant condition-by-direction-by-group interaction was found. Subjects with cavus feet had increased reach distances in 3 of 8 directions while wearing orthotics. Conclusions: Custom orthotics were associated with some improvements in static and dynamic postural control in subjects with cavus feet.