Article

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.
CI - (c) The International Society for Prosthetics and Orthotics 2014.

Langue : ANGLAIS