Factors Associated With Upper Extremity Functional Recovery Following Low-Frequency Repetitive Transcranial Magnetic Stimulation in Stroke Patients

Applications of Repetitive Transcranial Magnetic Stimulation to Improve Upper Limb Motor Performance After Stroke: A Systematic Review

BACKGROUND

Noninvasive brain stimulation (NIBS) is a promising technique for improving upper limb motor performance post-stroke. Its application has been guided by the interhemispheric competition model and typically involves suppression of contralesional motor cortex. However, the bimodal balance recovery model prompts a more tailored application of NIBS based on ipsilesional corticomotor function.

OBJECTIVE

To review and assess the application of repetitive transcranial magnetic stimulation (rTMS) protocols that aimed to improve upper limb motor performance after stroke.

METHODS

A PubMed search was conducted for studies published between 1st January 2005 and 1st November 2022 using rTMS to improve upper limb motor performance of human adults after stroke. Studies were grouped according to whether facilitatory or suppressive rTMS was applied to the contralesional hemisphere.

RESULTS

Of the 492 studies identified, 70 were included in this review. Only 2 studies did not conform to the interhemispheric competition model, and facilitated the contralesional hemisphere. Only 21 out of 70 (30%) studies reported motor evoked potential (MEP) status as a biomarker of ipsilesional corticomotor function. Around half of the studies (37/70, 53%) checked whether rTMS had the expected effect by measuring corticomotor excitability (CME) after application.

CONCLUSION

The interhemispheric competition model dominates the application of rTMS post-stroke. The majority of recent and current studies do not consider bimodal balance recovery model for the application of rTMS. Evaluating CME after the application rTMS could confirm that the intervention had the intended neurophysiological effect. Future studies could select patients and apply rTMS protocols based on ipsilesional MEP status.

Effects of cerebellar transcranial direct current stimulation on rehabilitation of upper limb motor function after stroke

Background

The cerebellum is involved in the control and coordination of movements but it remains unclear whether stimulation of the cerebellum could improve the recovery of upper limb motor function. Therefore, this study aimed to explore whether cerebellar transcranial direct current stimulation (tDCS) therapy could promote the recovery of upper limb motor function in patients who suffered a stroke.

Methods

In this randomized, double-blind, and sham-controlled prospective study, 77 stroke patients were recruited and randomly assigned to the tDCS group (n = 39) or the control group (n = 38). The patients received anodal (2 mA, 20 min) or sham tDCS therapy for 4 weeks. The primary outcome was the change in the Fugl-Meyer Assessment-Upper Extremity (FMA-UE) score from baseline to the first day after 4 weeks of treatment (T1) and 60 days after 4 weeks of treatment (T2). The secondary outcomes were the FMA-UE response rates assessed at T1 and T2. Adverse events (AEs) related to the tDCS treatment were also recorded.

Results

At T1, the mean FMA-UE score increased by 10.7 points [standard error of the mean (SEM) = 1.4] in the tDCS group and by 5.8 points (SEM = 1.3) in the control group (difference between the two groups was 4.9 points, P = 0.013). At T2, the mean FMA-UE score increased by 18.9 points (SEM = 2.1) in the tDCS group and by 12.7 points (SEM = 2.1) in the control group (the difference between the two groups was 6.2 points, P = 0.043). At T1, 26 (70.3%) patients in the tDCS group had a clinically meaningful response to the FMA-UE score compared to 12 (34.3%) patients in the control group (the difference between the two groups was 36.0%, P =0.002). At T2, 33 (89.2%) patients in the tDCS group had a clinically meaningful response to the FMA-UE score compared with 19 (54.3%) patients in the control group (the difference between the two groups was 34.9%, P = 0.001). There was no statistically significant difference in the incidence of adverse events between the two groups. In the subgroup analysis of different hemiplegic sides, the rehabilitation effect of patients with right hemiplegia was better than that of patients with left hemiplegia (P < 0.05); in the age subgroup analysis, different age groups of patients did not show a significant difference in the rehabilitation effect (P > 0.05).

Conclusion

Cerebellar tDCS can be used as an effective and safe treatment to promote recovery of upper limb motor function in stroke patients.

Trial registration

ChiCTR.org.cn, identifier: ChiCTR2200061838.

Feasibility of dance therapy using telerehabilitation on trunk control and balance training in patients with stroke: A pilot study

BACKGROUND

This randomized controlled trial aimed to investigate the effects of dance therapy using telerehabilitation on trunk control and balance training in patients with stroke and compare them with the effects of conventional treatment.

METHODS

We enrolled 17 patients with subacute or chronic stroke who were randomly assigned to either an experimental or a control group. In addition to conventional physical therapy, the experimental group (n = 9) participated in 40-minute, non-face-to-face, dance-therapy sessions and the control group (n = 8) received conventional physical therapy. The primary outcome measures were the Trunk Impairment Scale (TIS) scores to assess trunk control and balance function between the 2 groups as a measure of change from baseline to after the intervention.

RESULTS

We found that the TIS scores of the patients in the experimental group significantly improved (P = .017). The TIS results indicated non-inferiority within a predefined margin for dance therapy using telerehabilitation (difference = -0.86, 95% confidence interval [CI] = -2.21 to 0.50).

CONCLUSION

Dance therapy using telerehabilitation significantly improved the TIS scores in the experimental group and was not inferior to conventional rehabilitation treatment when compared in a non-inferiority test. The remote dance program may therefore have similar effects to those of conventional treatment regarding trunk-control improvement in patients with stroke.

Synergistic Effects of Scalp Acupuncture and Repetitive Transcranial Magnetic Stimulation on Cerebral Infarction: A Randomized Controlled Pilot Trial

This study investigated the synergistic effects of scalp acupuncture (SA) and repetitive transcranial magnetic stimulation (rTMS), known to be effective for cerebral infarction. This outcome-assessor-blinded, randomized controlled clinical trial included a per-protocol analysis to compare the efficacy of SA and electromagnetic convergence stimulation (SAEM-CS) and single or no stimulation. The trial was conducted with 42 cerebral infarction patients (control group, 12; SA group, 11; rTMS group, 8; SAEM-CS group, 11). All patient groups underwent two sessions of CSRT per day. SA, rTMS, and SAEM-CS were conducted once per day, 5 days per week, for 3 weeks. The primary outcome was evaluated using the Fugl–Mayer assessment (FMA). FMA Upper Extremity, FMA total, MBI, and FIM scores significantly increased in the rTMS group compared with the control group. Additionally, FMA Upper Extremity, FMA total, MBI and FIM scores significantly increased in the rTMS group compared with the SAEM-CS group. However, there were no significant changes in the SA or SAEM-CS groups. In conclusion, low-frequency rTMS in the contralesional hemisphere may have long-term therapeutic effects on upper extremity motor function recovery and improvements in activities of daily living. SAEM-CS did not show positive synergistic effects of SA and rTMS.

Effects and safety of combined rTMS and action observation for recovery of function in the upper extremities in stroke patients: A randomized controlled trial

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) modulates cortical excitability and facilitates motor learning to improve motor recovery after stroke. Action observation (AO) therapy effectively facilitates physical training for motor memory formation.

OBJECTIVE

To compare the effectiveness of rTMS alone with that of combined rTMS and AO for the functional recovery of upper extremity function in subacute stroke patients and to verify the safety of the interventions.

METHODS

The present study was a prospective, randomized controlled trial involving subacute unilateral stroke patients. In total, 22 patients were randomly assigned to 2 groups: the trial group (rTMS with AO) and the control group (rTMS alone). Both groups received 1 Hz rTMS (intensity: 120% of resting motor threshold; rMT) over the contralesional primary motor cortex for 20 minutes on 10 consecutive days. Trial group received rTMS while watching a video of 5 different complex hand movements. The functional parameters were the Brunnstrom stage, Fugl-Meyer assessment (FMA) score of the upper extremity, Manual Function Test (MFT) score, and grip power. The following motor evoked potential (MEP) parameters were recorded from the abductor pollicis brevis muscle: rMT, latency, and amplitude. Both parameters were measured before and after the 2 week intervention.

RESULTS

After the 2 week trial, the total FMA and MFT scores were significantly improved in both groups, but the MFT subscores of hand motor function and grip power were significantly improved in the combination therapy group only. In contrast, the changes (Δ) of FMA, MFT, grip power test, and MEP outcomes were not significantly different between the 2 groups. No adverse events or complications were reported.

CONCLUSIONS

Distal upper extremity function, as measured by MFT and grip power, was improved after rTMS and AO in combination. The combination of rTMS with AO may be applied safely to improve upper extremity function after stroke.

Safety and Efficacy of Accelerated Repetitive Transcranial Magnetic Stimulation Protocol in Elderly Depressed Unipolar and Bipolar Patients

OBJECTIVE

Major depressive disorder (MDD) is a prevalent condition in older adults. Although antidepressant drugs are commonly prescribed, efficacy is variable, and older patients are more prone to side effects. Repetitive transcranial magnetic stimulation (rTMS) is an alternative therapy used increasingly in the treatment of MDD. Even though recent studies have shown efficacy of rTMS in elderly depressed patients, the safety and efficacy of accelerated rTMS has not been studied in this population.

METHODS

Data were retrospectively analyzed for adults with treatment-resistant depression (N = 73, n = 19 ≥60years, n = 54 <60 years) who underwent an accelerated protocol of 30 sessions (2 sessions per day) of left dorsolateral prefrontal cortex high-frequency (20 Hz) rTMS.

RESULTS

There were statistically significant improvements in depression and anxiety symptoms from baseline to post-treatment in both age groups, but those 60years and older showed statistically greater improvement in depression and anxiety symptom scores (p = 0.01) than those less than 60. There were significantly more responders (p = 0.001) and remitters (p = 0.023) in the older group. The age groups did not differ significantly in clinical and demographic characteristics or severity of current depressive episode, although baseline anxiety was less severe in those 60years and older. Unipolar and bipolar patients had a similar clinical response, and treatment appeared to be well tolerated by all patients.

CONCLUSION

Our results suggest that accelerated rTMS protocol is a safe and effective treatment for unipolar and bipolar depressed subjects, including older adults.

Repetitive Transcranial Magnetic Stimulation Enhances Recovery in Central Cord Syndrome Patients

Objective

To investigate the effect of repetitive transcranial magnetic stimulation (rTMS) on neurological and functional recovery in patients with central cord syndrome (CCS) involving the upper extremities between the treated and non-treated sides of the treated group and whether the outcomes are comparable to that of the untreated control group.

Methods

Nineteen CCS patients were treated with high-frequency (20 Hz) rTMS over the motor cortex for 5 days. The stimulation side was randomly selected, and all the subjects received conventional occupational therapy during the rTMS-treatment period. Twenty CCS patients who did not receive rTMS were considered as controls. Clinical assessments, including those by the International Standard for Neurological Classification of Spinal Cord Injury, the Jebsen-Taylor Hand Function Test, and the O'Connor Finger Dexterity Test were performed initially and followed up for 1 month after rTMS treatment or 5 weeks after initial assessments.

Results

The motor scores for upper extremities were increased and the number of improved cases was greater for the treated side in rTMS-treated patients than for the non-treated side in rTMS-treated patients or controls. The improved cases for writing time and score measured on the Jebsen-Taylor Hand Function Test were also significantly greater in number on the rTMS-treated side compared with the non-treated side and controls. There were no adverse effects during rTMS therapy or the follow-up period.

Conclusion

The results of the application of high-frequency rTMS treatment to CCS patients suggest that rTMS can enhance the motor recovery and functional fine motor task performance of the upper extremities in such individuals.

Changes in Intracortical Excitability of Affected and Unaffected Hemispheres After Stroke Evaluated by Paired-Pulse Transcranial Magnetic Stimulation

OBJECTIVE

To assess the altered pattern of intracortical excitability of the affected and unaffected hemispheres in stroke patients using paired-pulse transcranial magnetic stimulation (TMS).

METHODS

We evaluated intracortical inhibition (ICI) and intracortical facilitation (ICF) in both hemispheres at acute and subacute stages of 103 stroke patients using paired-pulse TMS. The patients were divided into two groups: mild-to-moderate patients whose motor evoked potential (MEP) was recorded in the affected hemisphere; and severe patients whose MEP was not recorded in the affected hemisphere.

RESULTS

In mild-to-moderate patients, the value of ICI in the affected hemisphere was increased from 70.3% to 77.9% and the value of ICI in the unaffected hemisphere was decreased from 74.8% to 70.3% with eventual progression in acute to subacute stages of stroke. In severe patients, the value of ICI in the unaffected hemisphere was increased from 65.4% to 75.6%. The changes in ICF were not significantly different in this study.

CONCLUSION

We conclude that the unaffected hemisphere was more disinhibited than the affected hemisphere in acute phase of mild-to-moderate stroke, and the affected hemisphere was more disinhibited in the subacute stage. The unaffected hemisphere was inhibited in severe cases in acute-to-subacute phases of stroke. This finding facilitates appropriate neuromodulation of acute-to-subacute phases in mild-to-severe stroke patients.

Low-Frequency Repetitive Transcranial Magnetic Stimulation for Stroke-Induced Upper Limb Motor Deficit: A Meta-Analysis

Background and Purpose

This meta-analysis aimed to evaluate the therapeutic potential of low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) over the contralesional hemisphere on upper limb motor recovery and cortex plasticity after stroke.

Methods

Databases of PubMed, Medline, ScienceDirect, Cochrane, and Embase were searched for randomized controlled trials published before Jun 31, 2017. The effect size was evaluated by using the standardized mean difference (SMD) and a 95% confidence interval (CI). Resting motor threshold (rMT) and motor-evoked potential (MEP) were also examined.

Results

Twenty-two studies of 1 Hz LF-rTMS over the contralesional hemisphere were included. Significant efficacy was found on finger flexibility (SMD = 0.75), hand strength (SMD = 0.49), and activity dexterity (SMD = 0.32), but not on body function (SMD = 0.29). The positive changes of rMT (SMD = 0.38 for the affected hemisphere and SMD = −0.83 for the unaffected hemisphere) and MEP (SMD = −1.00 for the affected hemisphere and SMD = 0.57 for the unaffected hemisphere) were also significant.

Conclusions

LF-rTMS as an add-on therapy significantly improved upper limb functional recovery especially the hand after stroke, probably through rebalanced cortical excitability of both hemispheres. Future studies should determine if LF-rTMS alone or in conjunction with practice/training would be more effective.

Clinical Trial Registration Information

This trial is registered with unique identifier CRD42016042181.

Effects of virtual reality intervention on upper limb motor function and activity of daily living in patients with lesions in different regions of the brain

[Purpose] This study aimed to investigate whether a virtual reality (VR) intervention has an influence in improving the motor function and activities of daily living (ADLs) in patients with lesions in different regions of the brain. [Subjects and Methods] Eleven subjects with hemiplegic stroke were recruited in this study, which was conducted from January to February, 2017. They received a VR intervention once a day for 30 min, 5 times a week for 4 weeks. The Fugl-Meyer Assessment (FMA) and the Korean version of the Modified Barthel Index (K-MBI) were used to assess the post-stroke patients’ motor function and ADLs, respectively. [Results] There were significant differences in pre- and post-test outcomes of the Arm and Coordination and Speed (CS) in the FMA and K-MBI in the middle cerebral artery group (MCAG). Moreover, there were significant differences in all sub-tests of FMA and K-MBI in the Basal ganglia group (BGG). In addition, there were significant differences in the pre-test outcomes of Arm and pre- and post-test outcomes of Hand in the FMA between the two groups. [Conclusion] This study revealed that VR intervention improved the upper limb motor function and ADLs of post-stroke patients, especially those in the BGG.

Role of the Contralesional vs. Ipsilesional Hemisphere in Stroke Recovery

Following a stroke, the resulting lesion creates contralateral motor impairment and an interhemispheric imbalance involving hyperexcitability of the contralesional hemisphere. Neuronal reorganization may occur on both the ipsilesional and contralesional hemispheres during recovery to regain motor functionality and therefore bilateral activation for the hemiparetic side is often observed. Although ipsilesional hemispheric reorganization is traditionally thought to be most important for successful recovery, definitive conclusions into the role and importance of the contralesional motor cortex remain under debate. Through examining recent research in functional neuroimaging investigating motor cortex changes post-stroke, as well as brain-computer interface (BCI) and transcranial magnetic stimulation (TMS) therapies, this review attempts to clarify the contributions of each hemisphere toward recovery. Several functional magnetic resonance imaging studies suggest that continuation of contralesional hemisphere hyperexcitability correlates with lesser recovery, however a subset of well-recovered patients demonstrate contralesional motor activity and show decreased functional capability when the contralesional hemisphere is inhibited. BCI therapy may beneficially activate either the contralesional or ipsilesional hemisphere, depending on the study design, for chronic stroke patients who are otherwise at a functional plateau. Repetitive TMS used to excite the ipsilesional motor cortex or inhibit the contralesional hemisphere has shown promise in enhancing stroke patients' recovery.