The effect of fatigue on dynamic stability of patients with flat foot during walking

Pes planus can affect dynamic stability during walking, but there is little information about the effect of pes planus on dynamic stability in these patients, so the aim of this study was to assess the effect of fatigue on dynamic stability in patients with pes planus.

10 subjects with pes planus and 10 healthy subjects participated in this study. Data were collected by vicon motion anlaysis system with 4 cameras and 2 kistler forceplates. Fatigue protocol including 12 minutes of running performed and dynamic stability and spatio-temporal data were recorded before and after protocol. Dependent and independent t-test were used to analyze data at the set point of 0.05. Result; vertical excursion of centre of mass (COM) was significantly greater in pes planus compared to healthy group (p=0.01). After exhusting protocol, frontal excursion of centre of mass (COM) and step width was significantly greater in pes planus (p=0.03).

Fatigue reduces the dynamic stability of subjects with flat feet, which is associated with increased vertical and lateral displacement of the center of mass and increased step width. After exhaustion, subjects with flat feet are unstable on frontal plan these movements may increase the risk of injury, so these movements should be performed with greater caution.