Can Low-intensity Electromyographic Biofeedback Training on Tibialis Anterior Improve Strength and Balance in Chronic Stroke?

低劑量生物回饋儀訓練是否能增加中風患者的脛前肌肌力及站立平衡能力?

蔡佩玲(Peih-Ling Tsaih) ； 胡名霞(Ming-Hsia Hu) ； 石佑翎(Yu-Ling Shih) ； 林光華(Kwan-Hwa Lin)

《物理治療》 31卷4期 (2006/08) Pp. 227-236

摘要

背景與目的：本研究探討低劑量及低頻率之肌電生物回饋儀訓練對慢性中風患者脛前肌肌力及平衡能力改善的效果。方法：本研究為單盲設計之隨機分組控制實驗。十八位慢性中風患者被隨機分配於100%、50%漸減回饋組和對照組。訓練組接受每週二天、每天二十次肌肉用力、共持續六週的肌電生物回饋儀訓練患側脛前肌肌力。100%回饋組每次肌肉用力都給回饋；50%漸減回饋組其回饋頻率由100%漸減至5%，總回饋頻率為50%。每位受試者均接受訓練前三天內、完成六週訓練當日、訓練後二週和訓練後六週共四次評估。評估內容為手握測力器測量之脛前肌肌力及電腦動態平衡儀之平衡測量。結果：低劑量及低回饋頻率之肌電生物回饋儀訓練對中風患者脛前肌肌力在訓練後有改善的趨勢。三組之足底壓力中心到達前方目標區之花費時間隨著時間變化而有明顯改善。結論：低劑量及低回饋頻率肌電生物回饋儀訓練對慢性中風患者患側脛前肌肌力及平衡能力無明顯改善效果。建議臨床上仍需使用較高劑量之肌電生物回饋儀訓練。未來研究需增加受試者人數及嚴謹操控回饋方式以探討低頻率肌電生物回饋儀訓練對中風患者動作學習效果。脛前肌肌力之肌電生物回饋儀訓練似乎可增加慢性中風患者重心往前方位移之能力。

關鍵字

肌電生物回饋儀 ； 回饋頻率 ； 平衡 ； 動作學習 ； 中風

並列摘要

Background and Purposes: The purpose of this study was to investigate if low-intensity and reduced frequency of electromyographic (EMG) biofeedback training on the tibialis anterior (TA) muscle of the affected side can improve TA strength and standing balance in chronic stroke. Methods: This was a single blind randomized control trial. Eighteen subjects (11 males), aged 41 to 86 years (66.33±12.04 years), were randomly assigned to the three groups with equal numbers (control, 50% faded feedback and 100% feedback). In feedback groups, subjects practiced 20 trials of active ankle dorsiflexion on the affected side with EMG biofeedback during each training session twice a week for six weeks (totally 240 trials, approximately 108 minutes of training). Feedback was provided either after each trial (for the 100% feedback group) or faded (from 100% to 5% with an overall 50% feedback frequency for the 50% faded feedback group). The control group did not receive additional training in addition to their regularly scheduled treatment. All subjects were evaluated at the pre-training, post-training, 2 weeks follow-up and 6 weeks follow-up test. The variables were TA strength using the PowerTrack Ⅱ hand-held dynamometer (Jtech Medical Industries) and the standing balance using the Smart Balance Master system (NeuroCom Int. Inc.). Results: MANOVA for repeated measures failed to detect significant main effects between groups for either the TA strength or the standing balance. However, there was a trend toward improvement of TA strength at two weeks follow-up in the 50% faded group. Significant improvement was detected on the time to reach anterior target (p＜0.03) in all groups from pre-training to post-training. Conclusions: Our study failed to demonstrate significant effects of low-intensity and reduced EMG biofeedback frequency training in increasing TA strength on the affected side of the chronic stroke subjects. Based on the comparison of literature findings and our results, high-intensity training may be important for improving muscle strength by EMG biofeedback. Further study with increased training intensity and rigorous feedback schedule manipulation may be indicated to draw a more definite conclusion regarding the effects of EMG biofeedback training on TA muscle function in chronic stroke subjects.

並列關鍵字

EMG biofeedback ； Feedback frequency ； Balance ； Motor learning ； Stroke