Biomechanics of the Foot

INTRODUCTION

Relationship between lower extremity injury and muscle activation response and balance ability in ballet dancers

Among ballet dancers’ related injuries, ankle and foot injuries account for about 35%-55%. Previous studies have found that the dancers with injured feet may be good in balance on single leg standing, but with fair ballet performance skills. We used motion analysis, foot pressure plates and electromyography to record basic classical ballet movement (the first and the fifth basic movements, tiptoes, split jumps, and attitude) of the subjects to investigate the relationship between the balance ability and jumping performance and injury history. The results of the study showed that ankle injury history was highly correlated to medio-lateral balance ability, so it was suggested that the dancers should perform muscle and balance control training based on specific ballet movements.

Measurement of Medial Foot Arch of Children Aged 3 to 6

There are several causes of lower extremity injuries, among which is the hyper- or hypo- medial foot arch. Currently, the most common method to assess of medial foot arch is 2-dimensional measurement. The first purpose of this study is to use two digital camaras and mirror image method to construct a three-dimensional foot model, and to measure the development of medial foot arch of the children aged 3 to 6 by 3-dimensional descriptive method. The second purpose is to investigate the relationship between the medial foot arch and foot pressure distribution and joint force of lower extremities when children walk. The results of the study will help us to understand development of foot arch in young children and the role it plays in walking.