台灣學齡前發展遲緩兒童具有扁平足的比例較正常兒童高很多，然而大多數發展遲緩的成因多為原因不明。本研究目的是要瞭解發展遲緩兒童之足印分析結果與靜態平衡能力表現的相關性。以足印分析克拉克氏角度 (Clarke＇s angle)檢測足弓高度以評估扁平足的嚴重程度。本研究使用平衡測量儀Biodex BalanceSystem (BBS) 的電腦化系統來測試靜態平衡反應，以重心的前後、內外位移路徑與總位移路徑的平衡穩定指數 (stability index,SI) 來代表平衡反應能力，提供不明原因發展遲緩兒童靜態站立平衡能力表現的數據。研究選取五至六歲30位原因不
明型的發展遲緩兒童為研究對象。探討發展遲緩兒童足弓高度與靜態站立平衡控制能力的相關性。實驗的結果發現：一、發展遲緩兒童的足弓高度與靜態平衡反應是沒有顯著相關，並且足弓是正常足或扁平足的發展遲緩兒童，在靜態平衡的表現上是沒有差異的。二、單腳站立靜態平衡測試中，重心的前後位移變化情形與總位移變化情形呈高度相關性。重心的前後位移變化與內外位移變化無關。

Preschool children with developmental delay (DD) had a higher percentage of flat foot compared to their healthy counterparts. The resons for such high incidence of that foot in DD remains unknown. The purpose of this study was to explore therelationship between arch heights and static balance in 30 children with DD. Their arch height was measured using a
Clarke’s footprint angle method, while balance measures (overall stability index, anterior/posterior stability index, and medial/lateral stability index) were quantified using the Biodex Balance System (BBS). The results showed that no significant relationship was found between
foot arch height and static balance. In sum, there was no change in static balance ability in developmentally delayed children with and without flatfoot. The antero/posterior center of gravity sway during one-legged standing was highly correlated with the total center of gravity
sway, whereas the anterior-posterior center of gravity sway was not correlated with the medial/lateral sway.