BACKGROUND: Flat foot in children is a common deformity in which the medial longitudinal arch is reduced or eliminated.
OBJECTIVES: The objective of this article was to compare flat foot and healthy children on the displacement of the center of pressure and walking parameters in children with two common orthoses (functional foot orthosis and medical shoe).
STUDY DESIGN: Comparative study.
METHODS: This study included 30 children with flat foot and 20 healthy children as a control group. The step length and width, walking velocity, symmetry, and center of pressure (CoP) displacements were recorded and compared for three conditions: functional foot orthosis and regular shoe, a medical shoe and barefoot.
RESULTS: The results from the CoP displacements showed that the regular shoe with functional foot orthosis caused a significant decrease in the level of displacement of the CoP in flat foot children. The findings indicated a significant improvement in symmetry of steps and walking speed with the functional foot orthosis in comparison to the medical shoe in flat foot children.
CONCLUSION: The CoP displacement was decreased and the percentage of gait symmetry and walking speed were increased by the use of regular shoes with a functional foot orthosis in comparison to the medical shoes.
CLINICAL RELEVANCE: An orthopaedic shoe can be expensive, and in particular heavy with most children reluctant to wear it. This study focussed on the CoP displacement and selected gait parameters with an orthopaedic shoe and functional foot orthosis, and showed that a combined prescription of a functional foot orthosis and with regular shoes may be a useful alternative for children with moderate flat foot.
KEYWORDS: Center of pressure; flexible flat foot; functional foot orthosis; gait; medical shoe
BACKGROUND: Flexible flat foot is described as a reduction in the height of the medial longitudinal arch and may occur from abnormal foot pronation. A foot orthosis is thought to modify and control excessive pronation and improve arch height.
OBJECTIVE: To compare the immediate effect of three types of orthoses on foot mobility and the arch height index in subjects with flexible flat feet.
STUDY DESIGN: A quasi-experimental study.
METHOD: The dorsal arch height, midfoot width, foot mobility and arch height index were assessed in 20 participants with flexible flat feet (mean age = 23.2 ± 3 years) for three different foot orthosis conditions: soft, semi-rigid and rigid University of California Biomechanics Laboratory (UCBL).
RESULTS: Maximum midfoot width at 90% with arch mobility in the coronal plane was shown in the semi-rigid orthosis condition. The semi-rigid orthosis resulted in the highest mean foot mobility in 90% of weight bearing, and the rigid orthosis (UCBL) had the lowest mean foot mobility. The soft orthosis resulted in foot mobility between that of the rigid and the semi-rigid orthosis. UCBL orthosis showed the highest arch height index, and the semi-rigid orthosis showed the lowest mean arch height index.
CONCLUSION: Due to its rigid structure and long medial-lateral walls, the UCBL orthosis appears to limit foot mobility. Therefore, it is necessary to make an orthosis that facilitates foot mobility in the normal range of the foot arch. Future studies should address the dynamic mobility of the foot with using various types of foot orthoses.
CLINICAL RELEVANCE: Although there are many studies focussed on flat foot and the use of foot orthoses, the mechanism of action is still unclear. This study explored foot mobility and the influence of foot orthoses and showed that a more rigid foot orthosis should be selected based on foot mobility.
KEYWORDS: Foot orthosis; arch height index; foot mobility magnitude