探討半側偏癱腦性麻痺兒童的上肢動作計畫

Abstract

前言：腦性麻痺（簡稱腦麻）是兒童常見的動作障礙之一，起因為未成熟的大腦產生非進行性的損傷，而導致肢體受到不等程度的感覺動作損傷。其中，半側偏癱腦性麻痺佔整體腦麻約40%，典型症狀為身體半側受到影響，且上肢嚴重程度較大。然而，近年越來越多學者提出腦麻孩童整體動作表現不佳，不僅是因動作執行受損，動作計畫缺失也是潛在可能原因。動作計畫是指一個個體在執行動作之前，能根據目標預先計畫出動作過程的一項能力。然而，半側偏癱腦麻孩童的動作計畫表現尚未被全面性地了解。 目的：本研究目的如下（一）探討半側偏癱腦麻孩童的健側、患側手和年齡相配對的典型發展孩童的慣用、非慣用手的動作計畫表現差異。（二）探討半側偏癱腦麻孩童在不同情境下（單手、皆為任務手角色的雙手對稱、不對稱、一手任務一手輔助手角色的不對稱情境），和年齡相配對的典型發展孩童的動作計畫表現差異。（三）探討半側偏癱腦麻孩童的認知、動作表現與動作計畫表現之相關性。 方法：本研究有兩個階段，分別為設計杯瓶測驗（CBT）並進行試點研究，以及正式測驗。正式測驗共納入36位參與者，包含18位半側偏癱腦麻孩童（平均年齡10歲6個月±2歲2個月）以及18位年齡配對的典型發展孩童。認知、動作計畫表現和動作能力分別透過瑞文氏圖形推理測驗(RPM)、杯瓶測驗、鏡像動作評估（WTS）和墨爾本測驗（MA2）評估。 結果：混合重複測量變異數分析結果顯示半側偏癱腦麻孩童和典型發展孩童兩手的最終舒適效應（End-state-comfort, ESC），在單手和兩種不對稱情境下皆有顯著交互作用，而兩手的計畫時間（TIME）則是在單手和一手任務一手輔助手角色的不對稱情境有顯著交互作用。不論是最終舒適效應還是計劃時間，半側偏癱腦麻孩童的健側手與患側手都顯著的比典型發展孩童還要差，顯示出半側偏癱腦麻孩童的雙手都有某種程度的動作計畫損傷。此外，兩組孩童的最終舒適效應和計畫時間表現在不同情境都有顯著交互作用。半側偏癱腦麻孩童的患側手，在任務限制最多的不對稱情境中，表現出最多的最終舒適效應以及最短的計畫時間；而孩童的健側手，於雙手皆為任務手的雙手對稱情境，表現最少的最終舒適效應及顯著要長的計畫時間。另外，不論是健側手還是患側手，左側偏癱與右側偏癱的腦性麻痺孩童在最終舒適效應與計畫時間都沒有差異。皮爾森相關結果顯示，鏡像動作嚴重度和孩童雙手的動作計畫表現無相關，認知能力與雙手動作計畫時間呈現中度負相關，與最終舒適效應無關。而動作能力與患側手的最終舒適效應有中度正相關，與患側手計畫時間有中度負相關，而與孩童健側手的動作計畫表現沒有顯著相關。 結論：本研究透過更全面性的動作計畫任務，證實半側偏癱腦性麻痺孩童的雙手皆有某種程度的動作計畫損傷。此外，特別是當孩童的健側手在執行雙手對稱的任務時，容易因為受到患側手影響也使用了不佳的動作計畫策略，無法做出符合最終舒適效應的表現，而在雙手任務下，健側手的整體計畫時間也因為認知負荷較大，需要花費較單手任務下要長的計畫時間。有趣的是，兩種評估指標都顯示，一手任務一手輔助手角色的不對稱情境可以促進孩童的患側手有較佳的舒服姿勢以及較短的計畫時間表現。本研究亦發現半側偏癱腦麻孩童的認知能力和患側動作能力有可能影響其該側的動作計畫表現。因此，未來在研究以及臨床上，除了需要同時評估孩童兩手的動作計畫表現外，孩童本身的認知以及動作能力也須被考量，以利於提供更個人化且適切的治療方案。同時，治療師於臨床上使用雙手任務做介入時，也應更加謹慎，需提供患者明確的雙手動作指導或示範，才能確保將治療效果發揮到最大。

Introduction: Unilateral cerebral palsy (UCP) is the most common type of CP, and the unilateral impairment is due to non-progressive damage of the immature brain. Recent evidence suggests that motor planning deficits are also a possible underlying cause of compromised motor performance. Motor planning refers to the ability to anticipate the result of a task before motor execution. This ability plays an extremely important role in daily living. However, the outputs of motor planning performance of children with UCP have not been fully explored. Objective: This study aimed to develop a comprehensive task (1) to investigate the differences in the motor planning performance of the less-affected/more-affected hands of children with UCP compared with those of age-matched typically developing (TD) children, (2) to investigate the differences in the motor planning performance of children with UCP in different conditions (unimanual cup, bimanual symmetric cup–cup, bimanual asymmetric cup–cup, and bimanual asymmetric cup–bottle tasks) compared with that of age-matched TD children, and (3) to investigate the relationship between cognition, upper extremity motor performance and motor planning performance in children with UCP. Method: This study was conducted in two stages. The first was the development and pilot test of the Cup–Bottle Test (CBT), and the second was the formal test. In all, 18 children with UCP (mean age 10y 6 mo ± 2y 2mo) and 18 age-matched TD children were recruited for this study. Cognition, motor planning performance and motor ability were assessed by RPM, CBT, the Wood and Teuber Scale (WTS), and the Melbourne Assessment 2 (MA2). For purposes one and two, two-way mixed repeated-measures ANOVA was conducted to compare the end-state-comfort (ESC) and planning duration (TIME) differences of the UCP and TD groups. For purpose three, Pearson correlation was used to analyze the relationship between cognition, motor planning performance and upper extremity motor ability in the UCP group. Results: For ESC, significant differences were found between Group and Hand in the unimanual cup task and bimanual asymmetric cup–cup / cup–bottle tasks. For TIME, significant differences were found between Group and Hand in the unimanual cup task and bimanual asymmetric cup–bottle tasks. In both ESC and TIME, the UCP group showed poorer planning performance than that of the TD group in both hands for each condition. In addition, the two-way mixed RM ANOVA on ESC showed significant differences between Group and Condition in both hands (Dominant: p = 0.001; Non-Dominant: p = 0.012), and also revealed a significant interaction between Group and Condition in the dominant hands on TIME (p = 0.002). The post-hoc tests showed that the more-affected hand of children with UCP had the largest ESC percentage and shortest duration in the bimanual asymmetric cup–bottle task compared to the other conditions. On the other hand, the less-affected hand of children with UCP had the worst ESC in the bimanual asymmetric cup–bottle task compared to other conditions and longer planning durations in the bimanual conditions than in the unimanual condition. In addition, right and left UCP had no difference in ESC and TIME, regardless of less- or more-affected hand. In the UCP group, the Pearson correlation showed that WTS was not related to ESC or TIME in either hand, RPM was moderately negatively correlated with the TIME of both hands (rdominant = -0.534, p = 0.023, rnon-dominant = -0.566, p = 0.014), and had nothing to do with the ESC. However, there was a moderate positive correlation between MA2 and ESC of the more-affected hand (r = 0.579–0.685, all p < 0.05), and a moderate negative correlation between MA2 and TIME was found (r = -0.180 to -0.640, all p < 0.05). No significant correlation was found between MA2 and the performance of planning in the less-affected hand. Conclusion: This study demonstrates that both hands of children with UCP have deficits in motor planning. In addition, the simultaneous measurement of the ESC and TIME clearly indicated motor planning differences between the UCP and TD children. In addition, the cognition and motor ability of the more-affected hand may affect the performance of motor planning on that side. This study highlights the importance of considering both hands and the motor ability of the extremities for motor planning in evaluation so as to provide more personalized and tailored treatments. Clinical therapists should also be cautious when using bimanual tasks in interventions and provide patients with clear instructions or demonstrations to ensure the maximum therapeutic effect.