定量膝屈曲步行腦性麻痺患者穿著踝足部矯具之步態波形差異

Abstract

背景與目的: 踝足部矯具 (ankle-foot orthoses,AFO) 是常常被指定給腦性麻痺患者穿戴的步態矯正工具，對於步態的改善具有一定的療效，已有許多研究利用步態分析去比較各種不同的AFO在腦性麻痺患者的運動學及力動學表現上的不同，主要比較的變數包括時空參數，以及動力學參數曲線特定事件峰值，普遍認為AFO對踝關節運動的改善有幫助，但過去的研究大部分顯示AFO對於下肢近端關節的影響沒有明顯的差異；此研究將運用主成分分析法來定量並比較具有膝屈曲痙攣性腦性麻痺患者穿著不同AFO前後所得到的動力學參數波形差異特徵。 方法:本研究募集九位雙側痙攣性腦性麻痺的小孩，在站立期呈現的膝屈曲角度至少大於十度，共紀錄受測者只穿鞋(shoes only, SHOE)、穿著關節式踝足部矯具(hinged ankle-foot orthoses, HAFO)和固定式踝足部矯具(solid ankle-foot orthoses, SAFO)三種狀態走路時的運動學和力動學資料，經由計算獲得各受測者兩側的關節角度、力矩和功率分別進行主成分分析，為了凸顯狀態之間的差異，所以彼此兩兩進行分析程序，共分成三個組別進行主成分分析和比較：組別一:只穿鞋和穿著關節式踝足部矯具(SHOE-HAFO)、組別二: 只穿鞋和穿著固定式踝足部矯具(SHOE-SAFO)、組別三:穿著關節式和固定式踝足部矯具(HAFO-SAFO)，最後再經由統計分析比較不同狀態間獲得的主成分分數差異。 結果:由具有顯著差異的主成分中可觀察到，SAFO相較於不穿AFO和穿著HAFO，明顯減少了站立期踝背屈、膝屈曲和髖屈曲角度，但HAFO相對於不穿AFO和穿著SAFO在站立後半期有較大的功率吸收和釋放，HAFO相對於不穿AFO也增加了站立期的踝蹠屈肌力矩。 結論:主成分分析可以有效的由少數幾個主成分特徵描述複雜的資料結構，尤其是在具有高同質性的單個或多個狀態，更可以突顯其變異。此外，主成分分析更考慮了整個時間，而不是單一時間點，可以以另一個角度客觀且全面性的去探討整個資料差異。本研究結果顯示，SAFO除了減少踝關節的背屈，也可以改善近端關節的屈曲，而HAFO可以提供較正常的踝關節活動，但無法改善膝屈曲的步態。故針對具膝屈曲痙攣性腦性麻痺患者，本研究建議穿著SAFO，對膝屈曲改善效果較佳。

Objective: Ankle-foot orthoses (AFOs) are designed to correct the abnormal gait pattern in patients with celebral palsy. There were many studies which used gait analysis to test various types of AFOs for CP patients in their kinematics and kinetics performance. Many studies thought of AFOs as treatment intervention could improve pathological joint movement especially for ankle joint. But most of past studies concluded that AFOs can not improve knee and hip joints in the lower extremity. This study would use principal component analysis(PCA) to quantify the dynamic gait waveform and compare different types of AFOs for cerebral palsy with crouch gait. Methods: Nine spastic diplegic cerebral palsy patients with flexed knee gait (seven boys and two girls) anticipated in this study. Patients were recruited in this study, including those who had greater knee flexion angle (more than 10 degrees) in stance phase. There were three conditions including shoes only (SHOE), hinged ankle-foot orthoses (HAFO), and solid ankle-foot orthoses (SAFO) to test the biomechanical effects of AFOs. We collected kinematic and kinetic data to calculate joint angles, moments, joint powers, and use principal component analysis to analyze critical gait parameters. For enhancing comparisons between different orthotic conditions, All participants were separated into three groups depending on the pair of the orthotic intervention: (a) group 1: SHOE -HAFO (b) group 2: SHOE-SAFO (c) group 3: HAFO-SAFO. Results: There were some significant differences between groups in the joint angles. The SAFOs condition decreased ankle dorsiflexion angle, knee flexion angle and hip flexion angle when comparing with the SHOE and the HAFOs conditons. But HAFOs condition revealed more power absorption as well as power generation in the late stance phase when comparing with the SHOE and the SAFOs conditions. And the HAFOs condition also increased ankle plantar flexion moment in stance phase when comparing with the SHOE condition. Conclusion: The characteristic of the Principal component analysis could use fewer data to describe complex data structure effectively, especially in high homogeneous one or more conditions. Besides, principal component analysis considered the whole time period, not single gait event. The use of the PCA could analyze more objective and comprehensive in our study. And our study showed that SAFOs could decrease ankle dorsiflexion, knee flexion joint and hip flexion angle during gait. Although HAFOs could improve ankle joint angle, there were no significant improvement on knee flexion gait pattern. For spastic diplegic cerebral palsy patients with crouch gait, the results supported solid ankle-foot orthosis as effective treatments for patients with couch gait pattern.