Sinha Nirvik, Dewald Julius P A, Yang Yuan
Annu Int Conf IEEE Eng Med Biol Soc. 2024 Jul;2024:1-4. doi: 10.1109/EMBC53108.2024.10781597.
The goal of this study was to explore whether the stretch reflex-induced muscle activity is correlated with the expression of the flexion synergy and, therefore, can serve as a quantitative indicator of post-stroke motor impairment. Eleven stroke participants stroke were recruited for this study. Their forearm was connected to a robotic device that applied continuous position perturbations to the paretic elbow joint. The magnitude of EMG activity of the spastic biceps brachii was measured. The expression of the flexion synergy was determined using the increase of synergistic elbow flexion torque when subjects were gradually lifting their paretic arm with two derived measures: normalized flexion synergy area (NFSA) and the mean slope of the expression of flexion synergy (ΔFS). Significant positive correlations were found between spastic biceps EMG (predictor variable) and the flexion synergy expression (response variables), i.e., NFSA (ρ = 0.89, p < 0.001) and ΔFS (ρ = 0.73, p = 0.01). This result indicates that the perturbation-induced EMG activity can serve as a sensitive indicator of post-stroke motor impairments related to the expression of spasticity and flexion synergy and demonstrates that these motor impairments may be mechanistically linked.
本研究的目的是探讨牵张反射诱发的肌肉活动是否与屈曲协同运动的表达相关，从而能否作为中风后运动障碍的定量指标。本研究招募了11名中风患者。他们的前臂连接到一个机器人设备上，该设备对患侧肘关节施加连续的位置扰动。测量痉挛性肱二头肌的肌电图（EMG）活动幅度。当受试者逐渐抬起患侧手臂时，使用两种衍生测量方法来确定屈曲协同运动的表达：归一化屈曲协同运动面积（NFSA）和屈曲协同运动表达的平均斜率（ΔFS），即协同性肘关节屈曲扭矩的增加。在痉挛性肱二头肌肌电图（预测变量）与屈曲协同运动表达（反应变量）之间发现了显著的正相关，即NFSA（ρ = 0.89，p < 0.001）和ΔFS（ρ = 0.73，p = 0.01）。这一结果表明，扰动诱发的肌电图活动可作为与痉挛和屈曲协同运动表达相关的中风后运动障碍的敏感指标，并表明这些运动障碍可能在机制上存在联系。
