The Development and the Biomechanical and Physiological Effects of the Feet

• Main Authors: Chia-Hsin Chen, 陳嘉炘
• Other Authors: Gwo-Jaw Wang
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/58633473325973654507

博士 === 高雄醫學大學 === 醫學研究所博士班 === 95 === The purpose of this prospective study was to investigate the foot evolution in children, flatfoot definition and flatfoot incidence. The factors , such as body mass index, gender, age, district, were studied. Running and jumping performance and the clinical effects on flatfoot children were analyzed. The relationship between ankle positions and women with stress urine incontinence was also investigated. Furthermore, the effects of mechanical load on tendons or ligaments were studied. The assessment of foot morphology by using footprints is common. Medial longitudinal arch (MLA) has been used as a main reference to diagnose flatfoot. To measure foot types, contact area, pressure, and force variables, we used an EMED ST-4 capacitance mat transducer. These parameters with maximum pressure diagrams were analyzed by using Novel-Ortho software (version 0.87). The relationships between foot parameters and gender, body height or body weight were investigated. Flatfoot definition could be done by analyzing footprints. Therefore, we studied the flatfoot prevalence related to BMI, gender, places and physical activities. To assess pelvic floor muscle (PMF) activity in women with stress urinary incontinence, an adjustable ankle platform was used. PMF activity was measured with an intravaginal probe. In the force study, fibroblast showed gene expression under different mechanical loading by using Flexcell○R Tension Plus TM System. The changes of fiber morphology in stress deprived were measured. The results showed that sexual dimorphism in foot parameters. Girls had smaller foot length, width and heel width and boys had larger subarch angle, foot progressive angle, medial tarsal angle and anterior plantar angle. Subarch angle indicated well correlated to medial longitudinal arch and was used to define the flatfoot. When the degrees of the subarch angle were greater than 153.5°, a flatfoot was defined. From the results, foot length and width, heel angle and pressure indices were larger in non-flatfoot children. However, hallux angle, progressive angle and anterior plantar angle were larger in flatfoot groups. Higher flatfoot prevalence was also presented in obese children. Children with BMI greater than 95 percentile showed 3.58 times more than those with BMI between 15~85 percentile. Flatfoot prevalence in boys was 2.42 times than that in girls. The prevalence in urban students was 4.2 times than that in rural students. Obese or flatfoot students showed poorer physical fitness. Women with flatfeet might have the tendency of urine stress incontinence in this study. Furthermore, mechanical loading could promote fibroblast gene expression in vitro and human ligaments with stress deprived deteriorated into poor morphologies. The traditional method of acquiring ink footprint is a simple method measurement, but time-consuming, laborious and messy. Capacitance footprint is an easier way to overcome the disadvantages of obtaining ink footprints. In this study, foot data are useful for feet functional assessment and foot parameters can be applied in orthotic manipulation for flat feet in children. Reduced body weight and suitable orthoses to correct their flat feet may increase their jumping and running abilities. On the other hand, intrinsic muscle training in foot plantar area and reduced duration of footwear would get great benefit to reduce the flatfoot incidence in children. Women with flatfoot may have higher stress urine incontinence. From this study, we also assume that suitable mechanical loading might have promoted tendon or ligament function; however, overload or unload presented negative effects. Novel treatments with mechanical load are expected for the flatfoot children in the future.