The impact of transcranial direct current stimulation (tDCS) combined with modified constraint-induced movement therapy (mCIMT) on upper limb function in chronic stroke: a double-blind randomized controlled trial

<i>Purpose</i>: This pilot double-blind sham-controlled randomized trial aimed to determine if the addition of anodal tDCS on the affected hemisphere or cathodal tDCS on unaffected hemisphere to modified constraint-induced movement therapy (mCIMT) would be superior to constraints therapy alone in improving upper limb function in chronic stroke patients. <i>Methods</i>: Twenty-one patients with chronic stroke were randomly assigned to receive 12 sessions of either (i) anodal, (ii) cathodal or (iii) sham tDCS combined with mCIMT. Fugl–Meyer assessment (FMA), motor activity log scale (MAL), and handgrip strength were analyzed before, immediately, and 1 month (follow-up) after the treatment. Minimal clinically important difference (mCID) was defined as an increase of ≥5.25 in the upper limb FMA. <i>Results</i>: An increase in the FMA scores between the baseline and post-intervention and follow-up for active tDCS group was observed, whereas no difference was observed in the sham group. At post-intervention and follow-up, when compared with the sham group, only the anodal tDCS group achieved an improvement in the FMA scores. ANOVA showed that all groups demonstrated similar improvement over time for MAL and handgrip strength. In the active tDCS groups, 7/7 (anodal tDCS) 5/7 (cathodal tDCS) of patients experienced mCID against 3/7 in the sham group. <i>Conclusion</i>: The results support the merit of association of mCIMT with brain stimulation to augment clinical gains in rehabilitation after stroke. However, the anodal tDCS seems to have greater impact than the cathodal tDCS in increasing the mCIMT effects on motor function of chronic stroke patients.Implications for RehabilitationThe association of mCIMT with brain stimulation improves clinical gains in rehabilitation after stroke.The improvement in motor recovery (assessed by Fugl–Meyer scale) was only observed after anodal tDCS.The modulation of damaged hemisphere demonstrated greater improvements than the modulation of unaffected hemispheres.

研究目的：本项先导性双盲假对照随机试验旨在探究，在改良强制性运动疗法（modified constraint-induced movement therapy, mCIMT）基础上联合患侧半球阳极经颅直流电刺激（anodal tDCS）或健侧半球阴极经颅直流电刺激（cathodal tDCS），是否相较于单纯约束诱导运动疗法，能更有效地改善慢性脑卒中患者的上肢功能。
研究方法：21例慢性脑卒中患者被随机分配接受12次治疗，分组为：(i) 阳极经颅直流电刺激联合改良强制性运动疗法、(ii) 阴极经颅直流电刺激联合改良强制性运动疗法，以及(iii) 假刺激经颅直流电刺激（sham tDCS）联合改良强制性运动疗法。分别于治疗前、治疗即刻及治疗后1个月（随访期）对患者的Fugl-Meyer评估量表（Fugl–Meyer assessment, FMA）评分、运动活动日志量表（motor activity log scale, MAL）得分以及握力进行评估分析。本研究将最小临床重要差异（minimal clinically important difference, mCID）定义为上肢FMA评分升高≥5.25分。
研究结果：研究观察到，活性经颅直流电刺激组患者的基线至干预后及随访期的FMA评分均有所升高，而假刺激组未出现此类变化。在干预后及随访期，与假刺激组相比，仅阳极经颅直流电刺激组的FMA评分得到显著改善。方差分析（analysis of variance, ANOVA）结果显示，所有组的MAL评分及握力均随时间呈现相似程度的改善。在活性经颅直流电刺激组中，阳极经颅直流电刺激组7/7例、阴极经颅直流电刺激组5/7例患者达到了最小临床重要差异，而假刺激组仅3/7例患者达到该标准。
研究结论：本研究结果证实，改良强制性运动疗法联合脑刺激可增强脑卒中后康复的临床获益。但相较于阴极经颅直流电刺激，阳极经颅直流电刺激在增强改良强制性运动疗法对慢性脑卒中患者运动功能的改善效果方面，似乎具有更显著的作用。
康复启示：改良强制性运动疗法联合脑刺激可提升脑卒中后康复的临床获益。仅在接受阳极经颅直流电刺激的患者中，观察到运动功能恢复（通过Fugl-Meyer量表评估）得到改善。对受损大脑半球的经颅直流电刺激调控，相较于对未受损半球的调控，能带来更显著的康复改善。