學童扁平足盛行率之調查與矯正輔具對步態之評估

The investigation of flatfoot prevalence in school children and the orthotic effect on gait performance

鍾孟容

指導教授 ： 王茂駿

國立清華大學/工學院/工業工程與工程管理學系/博士(2009年)

摘要

扁平足是常見的兒童足部問題，本研究目的為調查台灣兒童扁平足盛行率、建立人體計測資料庫和評估矯正鞋墊對於扁平足兒童在生理和心理反應之影響。
本研究分成兩個階段進行。第一階段招募1024位兒童參與足部篩檢與人體計測等實驗，藉由三次元人體測量儀、數位捲尺和足印採集器來收集足部尺寸資料，並透過專業醫生來進行足部問題診斷。其研究結果指出扁平足盛行率隨著年齡的增加而逐漸下降，平均年齡5至13歲兒童的盛行率約28%，且男孩(35%)的盛行率高於女孩(20%)。此外，兒童過重及肥胖的比率約為20%，且肥胖的兒童具有較高的扁平足盛行率、較大的足部尺寸以及較小的足寬站坐改變量。而扁平足的兒童則是具有較低的足部高度尺寸和較大的足長站坐改變量。
第二階段的研究在於了解不同矯正鞋具的設計對於扁平足兒童在下肢運動學、動力學、肌肉活動度和主觀心理感受等反應的影響。本研究將21位受試者(5至11歲)分為實驗組和對照組，實驗組為9位扁平足兒童(足弓指標大於3)，對照組為12位正常足兒童。在實驗組合方面，實驗組須進行四項實驗組合，分別為赤腳、穿鞋、穿SMO (Supra-Malleolar Orthosis) 和穿UCBL (University of California Biomechanics Laboratory) 鞋墊；對照組則進行赤腳和穿鞋兩項實驗組合。
研究結果顯示扁平足兒童在行走時具有較大的關節角度變化、較高的肌肉活動度、較低的垂直地面反作用力和較晚的垂直和內外地面反作用力第一波峰出現時間。在矯正鞋墊評估方面，SMO和UCBL皆能減少膝關節和踝關節變化角度、降低脛前肌的肌肉活動度和提早內外地面反作用力第一波峰出現時間。此外，SMO更具有減少髖關節和增加垂直地面反作用力的功能。本研究結果指出，雖然SMO具有較多的改善功效，但卻容易造成較高的不舒適度，因此，若能改善SMO的舒適性，將會更有助於扁平足患者的穿戴和行走。

關鍵字

扁平足 ； 步態 ； 矯正鞋墊 ； 足部尺寸

並列摘要

Flatfoot is one of the most common foot pathology for children. This study aims to investigate the prevalence of flatfoot for Taiwanese children, the anthropometric database of children with and without flatfoot, as well as the effect of the two different types of commonly used orthoses on objective and subjective responses.
Two experiments are included. In the first stage, the prevalence of flatfoot and the anthropometric database of school children in Taiwan have been established. A total of 1024 school children (549 boys and 475 girls) with age 5 to 13 years old participated in this study. Fifteen foot dimensions were measured using a 3D coordinate measuring probe, digital tape measure and Harris mat imprint. The results show that the prevalence of flatfoot for 5 to 13 years old children was 28% with a decreasing trend with age. The prevalence of flatfoot was 35% in boys and 20% in girls. The percent of overweight and obese children was 20%. Obese children have a higher frequency of flatfoot, greater foot dimensions, and less change in foot breadth between weight-bearing and non-weight-bearing conditions than normal weight children. Children with flatfoot have lower foot height and greater foot length change than children with normal feet.
In the second stage, through the laboratory experiments, the effect of different orthotic design on the kinematics, kinetics and muscle activity of lower extremity, as well as the rating of perceived exertion were evaluated. Two groups of children with age of 5 to 11 years old were recruited: nine children with flatfoot (arch index above 0.3) and twelve children with normal foot. Flatfoot group has four experiment conditions: the barefoot, shoe-only, Supra-Malleolar Orthosis (SMO), and University of California Biomechanics Laboratory (UCBL) orthosis conditions; while normal foot group has only two experiment conditions: barefoot and shoe-only conditions.
The findings show that children with flatfoot tend to walk with the greater joint motions and higher muscle activities of lower extremity, as well as lower vertical ground reaction force (GRF) and longer durations of the first peak forces of vertical and medical-lateral GRFs than those of normal foot children. For the orthotic evaluation, the results indicate that both the SMO and UCBL orthoses can successfully reduce the joint motion of knee and ankle, the mean muscle activity of tibialis anterior, as well as facilitate the occurrence of the first medial-lateral GRF. In addition, the SMO can further reduce the range of hip flexion and increase the vertical GRF. Although the SMO has more positive impact on gait performance than the UCBL orthosis, but it will cause higher discomfort in ankle and lateral forefoot areas. Therefore, the comfort of SMO should be improved, so that it would become more suitable for flatfoot children to use.

並列關鍵字

Flatfoot ； Gait ； Orthosis ； Anthropometry

參考文獻

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