Plantar Pressure Distribution in Patients with Flexible Flatfoot: Measured by Platform System and In-Shoe System

功能性扁平足病患之足底壓力分布：雙元足底壓力測試系統

鄧筑文(Alice Chu Wen Tang) ； 吳和穆(Ho Mu Wu) ； 陳智光(Chih-Kuang Chen) ； 鄧復旦(Simon Fuk Tan Tang)

《台灣復健醫學雜誌》 45卷2期 (2017/12) Pp. 57-65

https://doi.org/10.6315/2017.45(2)02

摘要

Flatfoot is characterized with insufficiency of the medial longitudinal arch and flexible flatfoot is the most predominant type which leads to numerous clinical problems. This study aimed at investigating the plantar pressure distribution in flexible flatfoot patients with platform system and in-shoe system. Nineteen flexible flatfoot patients and fifteen normal subjects were recruited. Foot Function Index (FFI) was used for subjective symptoms report, and higher scores indicated worse clinical condition. Plantar pressure were assessed with Emed-X system and Pedar in-shoe system. Student independent-t test was used for statistical analysis, and statistical significance was set at p＜0.05. The results showed that the total score of FFI was significantly higher in flexible flatfoot patients. Emed-X system revealed that there were significantly greater contact area, peak pressure, foot maximum force and force-time integral in the medial midfoot area in flexible flatfoot patients. While Pedar in shoe system showed that there was significant decrease of peak pressure in lateral rearfoot. In conclusion, the findings of Emed-X system confirmed the crucial change of medial midfoot in flexible flatfoot patients, while the findings of Pedar in-shoe system illustrated the alteration of lateral rearfoot. These biomechanic features can be further applied in the orthosis design.

關鍵字

flatfoot ； plantar pressure ； emed ； pedar in-shoe

並列摘要

扁平足之特點為內側縱足弓支撐性不佳，而功能性扁平足又是扁平足中盛行率最高的足型。本篇研究旨在調查扁平足患者與正常足型者於足底接觸面積(contact area)，足底最高壓力(peak pressure)，最大足底受力(foot maximum force)，以及衝力（force-time integral）等足底生物力學參數之差異。共19 位功能性扁平足患者與15 位正常足型者參與本研究。臨床症狀以足部功能指數(functional foot index)量化，越高分代表功能越差; 而足部力學參數使用兩種足底壓力測試方法，包括平台測試系統(Emed-X system) 以及鞋內感測系統（Pedar in-shoe system）。應用t-test 為統計方法，定義p＜0.05 為有意義。結果顯示，扁平足患者具較高的足部功能指數(functional foot index)。而平台測試系統(Emed-X system)結果顯示，扁平足患者在足部中內側具較高的足底接觸面積(contact area)，足底最高壓力(peak pressure)，最大足底受力(foot maximum force)，以及衝力（force-time integral）。鞋內感測系統（Pedar in-shoe system）則顯示扁平足患者在足外後側具較低的足底最高壓力(peak pressure)。結論：平台測試系統(Emed-X system)呈現了扁平足患者在足內側的生物力學改變，而鞋內感測系統（Pedar in-shoe system）則描繪出足外側相對應的改變。此生物力學特性可進一步應用於未來的足部輔具製作。

並列關鍵字

扁平足(flatfoot) ； 足底壓力(plantar pressure) ； 足底壓力平台測試系統(emed) ； 鞋內感測系統(pedar in-shoe)

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