Effects of robot-assisted task-oriented upper limb motor training on neuroplasticity in stroke patients with different degrees of motor dysfunction: A neuroimaging motor evaluation index

Effects of training with a rehabilitation device (Rebless®) on upper limb function in patients with chronic stroke: A randomized controlled trial

BACKGROUND

Upper limb dysfunction is one of the most common sequelae of stroke and robotic therapy is considered one of the promising methods for upper limb rehabilitation.

OBJECTIVE

This study aimed to explore the clinical effectiveness of upper limb training using a rehabilitation robotic device (Rebless®) for patients with stroke.

METHODS

In this prospective, unblinded, randomized controlled trial, patients were randomly assigned to receive robotic training (experimental group, n = 15) or conventional therapy (control group, n = 15). Both groups received upper limb training lasting for 30 minutes per session with a total of 10 training sessions within 4 weeks. Motor function, functional evaluation, and spasticity were clinically assessed before and after the training. Cortical activation was measured using functional near-infrared spectroscopy at the 1st and 10th training sessions.

RESULTS

The experimental group demonstrated a significant improvement in the Fugl-Meyer assessment-upper extremity score and the modified Ashworth scale grade in elbow flexors. The cortical activity of the unaffected hemisphere significantly decreased after 10 training sessions in the experimental group compared with the control group.

CONCLUSIONS

The experimental group showed significant improvement in the Fugl-Meyer assessment-upper extremity score and spasticity of elbow flexors and had significantly decreased cortical activity of the unaffected hemisphere. Training with Rebless® may help patients with chronic stroke in restoring upper limb function and recovering the contralateral predominance of activation in motor function.

Upper limb motor assessment for stroke with force, muscle activation and interhemispheric balance indices based on sEMG and fNIRS

Introduction

Upper limb rehabilitation assessment plays a pivotal role in the recovery process of stroke patients. The current clinical assessment tools often rely on subjective judgments of healthcare professionals. Some existing research studies have utilized physiological signals for quantitative assessments. However, most studies used single index to assess the motor functions of upper limb. The fusion of surface electromyography (sEMG) and functional near-infrared spectroscopy (fNIRS) presents an innovative approach, offering simultaneous insights into the central and peripheral nervous systems.

Methods

We concurrently collected sEMG signals and brain hemodynamic signals during bilateral elbow flexion in 15 stroke patients with subacute and chronic stages and 15 healthy control subjects. The sEMG signals were analyzed to obtain muscle synergy based indexes including synergy stability index (SSI), closeness of individual vector (CV) and closeness of time profile (CT). The fNIRS signals were calculated to extract laterality index (LI).

Results

The primary findings were that CV, SSI and LI in posterior motor cortex (PMC) and primary motor cortex (M1) on the affected hemisphere of stroke patients were significantly lower than those in the control group (p < 0.05). Moreover, CV, SSI and LI in PMC were also significantly different between affected and unaffected upper limb movements (p < 0.05). Furthermore, a linear regression model was used to predict the value of the Fugl-Meyer score of upper limb (FMul) (R2 = 0.860, p < 0.001).

Discussion

This study established a linear regression model using force, CV, and LI features to predict FMul scale values, which suggests that the combination of force, sEMG and fNIRS hold promise as a novel method for assessing stroke rehabilitation.

Assessing the effectiveness of biofeedback therapy in the rehabilitation of limb motor dysfunction after stroke and the influencing factors of disease-related shame

OBJECTIVE

To evaluate the effectiveness of biofeedback therapy in the rehabilitation of limb motor dysfunction after stroke and the factors influencing disease-related shame.

METHODS

Medical records of 118 patients with limb motor dysfunction after stroke, treated in 521 Hospital of the Norinco Group from October 2019 to November 2022, were collected. The 56 patients in control group received conventional rehabilitation training, while the other 62 patients in observation group received electromyographic biofeedback therapy in addition to conventional treatment. The therapeutic effects of both groups were evaluated and compared after 4 weeks of treatment. Changes in FMA (Fugl-Meyer Motor Function Assessment Scale), mRS (Modified Rankin Scale), ADL (Activities of Daily Living Scale), and SSS (Stroke Stigma Scale) were compared before and after treatment. Multivariate logistic regression analysis was used to analyze the factors influencing disease-related shame after treatment. The effectiveness of risk factors in predicting disease-related shame was analyzed using receiver operating characteristic (ROC) curves.

RESULTS

Upon intervention, significant gains were noted in FMA and ADL scores, with reductions in mRS and SSS (P<0.0001). After 4 weeks, the observation group showed higher FMA and ADL scores and lower mRS and SSS (P<0.0001 for FMA and ADL; P<0.05 for mRS and SSS). Logistic regression identified age ≥60 (OR 8.045, P<0.001), income <4000 yuan (OR 0.187, P=0.002), and pretreatment ADL (OR 0.047, P<0.001) as predictors of disease-related shame. The AUC for age, household monthly income, and pretreatment ADL score were 0.595 (P=0.089), 0.608 (P=0.053), and 0.750 (P<0.001), respectively, demonstrating pretreatment ADL score as the most accurate predictor of disease-related shame.

CONCLUSIONS

Electromyographic biofeedback therapy has a significant effect on the rehabilitation of stroke patients, especially on motor recovery and activities of daily living. Age, monthly family income and pre-treatment ADL scores are key factors influencing disease-related shame.

Effects of transcranial magnetic stimulation on dynamic functional networks in stroke patients as assessed by functional near-infrared spectroscopy: a randomized controlled clinical trial

Studies have shown that there is heterogeneity in the efficacy bewteen the low-frequency (LF) and high-frequency (HF) repetitive transcranial magnetic stimulation (rTMS), but the neural mechanisms underlying the differences in efficacy remain unclear. This study aimed to investigate the specific effects of LF- and HF-rTMS on cortial functional network and the process of neural regulation. A total of sixty-eight patients with hemiplegic motor impairment after stroke were randomly allocated to one of three groups: the LF-rTMS, HF-rTMS, and sham groups. Tissue concentrations of oxyhaemoglobin and deoxyhaemoglobin oscillations in cerebral cortex regions were measured by functional near-infrared spectroscopy (fNIRS) in the resting and rTMS states. Four specific time-windows were divided from the trial duration to observe dynamic changes in cortical haemodynamic responses. Compared with sham, LF-rTMS significantly induced the activation of the contralesional superior frontal cortex and premotor cortex, and continuously regulated ipsilesional hemisphere functional networks in stroke patients. However, HF-rTMS did not induce a significant neurovascular coupling response. Our study provided evidence that LF- and HF-rTMS interventions induced different neurovascular coupling responses and demonstrated the cortical functional network change process of rTMS in specific time-windows. These findings may help to understand the differences in the efficacy of rTMS modalities.

Upper limb intelligent feedback robot training significantly activates the cerebral cortex and promotes the functional connectivity of the cerebral cortex in patients with stroke: A functional near-infrared spectroscopy study

Background

Upper limb intelligence robots are widely used to improve the upper limb function of patients with stroke, but the treatment mechanism is still not clear. In this study, functional near-infrared spectroscopy (fNIRS) was used to evaluate the concentration changes of oxygenated hemoglobin (oxy-Hb) and deoxyhemoglobin (deoxy-Hb) in different brain regions and functional connectivity (FC) of the cerebral cortex in patients with stroke.

Method

Twenty post-stroke patients with upper limb dysfunction were included in the study. They all received three different types of shoulder joint training, namely, active intelligent feedback robot training (ACT), upper limb suspension training (SUS), and passive intelligent feedback robot training (PAS). During the training, activation of the cerebral cortex was detected by fNIRS to obtain the concentration changes of hemoglobin and FC of the cerebral cortex. The fNIRS signals were recorded over eight ROIs: bilateral prefrontal cortices (PFC), bilateral primary motor cortices (M1), bilateral primary somatosensory cortices (S1), and bilateral premotor and supplementary motor cortices (PM). For easy comparison, we defined the right hemisphere as the ipsilesional hemisphere and flipped the lesional right hemisphere in the Nirspark.

Result

Compared with the other two groups, stronger cerebral cortex activation was observed during ACT. One-way repeated measures ANOVA revealed significant differences in mean oxy-Hb changes among conditions in the four ROIs: contralesional PFC [F_{(2, 48)} = 6,798, p < 0.01], ipsilesional M1 [F_{(2, 48)} = 6.733, p < 0.01], ipsilesional S1 [F_{(2, 48)} = 4,392, p < 0.05], and ipsilesional PM [F_{(2, 48)} = 3.658, p < 0.05]. Oxy-Hb responses in the contralesional PFC region were stronger during ACT than during SUS (p < 0.01) and PAS (p < 0.05). Cortical activation in the ipsilesional M1 was significantly greater during ACT than during SUS (p < 0.01) and PAS (p < 0.05). Oxy-Hb responses in the ipsilesional S1 (p < 0.05) and ipsilesional PM (p < 0.05) were significantly higher during ACT than during PAS, and there is no significant difference in mean deoxy-Hb changes among conditions. Compared with SUS, the FC increased during ACT, which was characterized by the enhanced function of the ipsilesional cortex (p < 0.05), and there was no significant difference in FC between the ACT and PAS.

Conclusion

The study found that cortical activation during ACT was higher in the contralesional PFC, and ipsilesional M1 than during SUS, and showed tighter cortical FC between the cortices. The activation of the cerebral cortex of ACT was significantly higher than that of PAS, but there was no significant difference in FC. Our research helps to understand the difference in cerebral cortex activation between upper limb intelligent feedback robot rehabilitation and other rehabilitation training and provides an objective basis for the further application of upper limb intelligent feedback robots in the field of stroke rehabilitation.