2011-08-012024-05-13https://scholars.lib.ntu.edu.tw/handle/123456789/648698摘要：研究背景與目的：力量(force)的產生與控制是順利進行日常生活活動非常重要的神經肌肉控制機制。出力程度控制不良為導致中風患者動作障礙的重要原因，肌電生物回饋儀(EMG biofeedback)是其學習出力程度控制經常被建議使用的有利工具。基於動作技巧學習理論，不同出力目標的變異練習比相同出力目標的固定練習更能促進動作技巧學習。肌電生物回饋儀非常適合進行變異練習之出力程度控制訓練，然而目前的研究尚未對其療效提出有利的證據。近代神經科學研究顯示，動作訓練伴隨的大腦重組和神經再塑是中風患者動作功能恢復的基礎。肌電生物回饋儀輔助之出力程度控制訓練所誘發的神經再塑令人好奇。利用穿顱磁刺激(Transcranial Magnetic Stimulation，TMS)探討運動訓練促使動作功能恢復的神經塑性與機制，有利於尋找安全、有效的治療參數。本研究利用肌電生物回饋儀進行變異練習之脛前肌出力程度控制訓練，探討對慢性中風患者平衡及行走相關功能的療效與伴隨的穿顱磁刺激誘發之神經興奮性變化。研究設計與方法：單盲設計之隨機分組控制實驗。所有受試者被隨機分配於三組：變異練習(variable practice)、固定練習(constant practice)和控制組。預計收案60人，每組20人。每位受試者均接受30分鐘、每週三次、共六週的脛前肌肌電生物回饋儀訓練。變異練習組分別以當次最大肌電量的100%、75%、50%及25%為隨機訓練目標。固定練習組以當次最大肌電量為訓練目標。控制組每次盡全力做最大收縮之偽肌電生物回饋儀訓練。每位受試者接受訓練前、後、訓練後二週和六週共四次評估。評估項目為與平衡及行走相關的動作功能，包括脛前肌出力錯誤率、脛前肌肌力、踝關節背屈活動角度、小腿後肌痙攣(Calf muscle spasticity)、電腦動態平衡儀之動態平衡、行走速度、計時起走測驗(Timed Up and Go test, TUGT)及六分鐘行走測驗(Six-minute Walking test, SMWT)與穿顱磁刺激誘發之神經興奮性，包括脛前肌運動誘發電位(Motor evoked potentials, MEPs)之閾值(MEP threshold)、潛伏期(MEP latency)與徵召曲線(recruitment curve)。以SPSS 13.0進行統計分析。預期效果與臨床應用：預期三組受試者在訓練後身體位移的距離、行走速度與神經興奮性皆有明顯變化。然而，只有變異練習組具有在平衡與行走時出力程度控制的能力及伴隨的脛前肌運動誘發電位徵召曲線變化。<br> Abstract: Background: Force generation and force level control are important neuromuscular control mechanism for successful execution of movement for our daily activities. Impaired force level control is a major deficit of motor control in people with stroke. Electromyograghic biofeedback (EMG biofeedback) has been suggested by researchers and clinicians to be a useful and effective tool for enhancing control of force level during motor skill learning for people with stroke. Based on the concept of motor-skill learning, practice with variable force levels may be more effective than practice with a constant force level to enhance movement performance. The EMG biofeedback provides a suitable tool for such practice of force level control and hence for motor skill learning. However, research literatures thus far have yet to provide convincing evidences to support this claim. Neural imaging studies have shown corresponding brain reorganization and neural plasticity following physical practice of movement skills in people with stroke. It is curious whether EMG biofeedback augmented physical practice of motor skills enhances brain reorganization. Using brain mapping techniques, in particular, the transcranial magnetic stimulation (TMS), we could investigate neural plasticity accompanying motor function changes induced by physical training, and hence may help to develop safer and more effective training parameters. The purpose of this study is to examine the effects of variable practiced EMG biofeedback training emphasized on force level control of the ankle muscle on balance and gait performance and the corresponding changes of corticospinal excitability using TMS in people with chronic stroke. Study Design and Methods: This study is a single-blind randomized controlled trial. Sixty participants will be recruited and randomly assigned to one of the three groups: constant practice, variable practice and control group. Each participant receives 3 days per week for a total of 6 weeks of EMG biofeedback assisted force level control training of the Tibialis Anterior (TA) muscle. For the variable practice group, the participants will practice exertion of force output levels at 100%, 75%, 50%, and 25% of maximal TA muscle strength with EMG feedback. For the constant practice group, the goal of force level control training is 100% of maximal strength. The control group participants will practice maximal TA muscle control without EMG feedback. Balance and gait-related motor functions, such as TA force control error, TA strength, ankle range of motion, calf muscle spasticity, walking speed, Timed Up and Go test, Six-minute Walking test, and dynamic balance test and corticospinal excitability including threshold, latency, and recruitment curve of TA motor evoked (MEP) potentials will be evaluated at baseline, post-training, two weeks after training and six weeks after training. SPSS 13.0 will be used for statistical analysis. Anticipated results: We anticipate that all three groups of participants may demonstrate changes in maximal weight shift amplitude, gait speed and corticospinal excitability. However, only the variable practice group will demonstrate ability to modify and vary force level control during balance and gait tasks, and reveal corresponding changes in recruitment curve of TA MEP.PharmacovigilanceActive SurveillanceRisk Signal DetectionDrug Risk Management