Modulation of sensorimotor cortex by repetitive peripheral magnetic stimulation

Cortical Mechanisms Underlying Effects of Repetitive Peripheral Magnetic Stimulation on Dynamic and Static Postural Control in Patients with Chronic Non-Specific Low Back Pain: A Double-Blind Randomized Clinical Trial

INTRODUCTION

Patients with chronic non-specific low back pain (CNLBP) often experience impaired postural control, contributing to pain recurrence. Although repetitive peripheral magnetic stimulation (rPMS) combined with core muscle training (CMT) could improve postural control, its neural mechanism remains unclear. This study aims to investigate the postural control-related cortical mechanism of the effect of rPMS on patients with CNLBP.

METHODS

This unicentric, prospective, randomized, double-blind, controlled trial was conducted in a public hospital from May to December 2023. A total of 40 patients (27 females and 13 males, mean age 29.38 ± 7.72) with CNLBP were randomly assigned to either the rPMS group (real rPMS with CMT) or the sham-rPMS group (sham-rPMS with CMT) for 12 sessions over 4 weeks. The rPMS was applied to the lumbar paravertebral multifidus muscle on the painful side. Pain and disability were quantified using the visual analog scale (VAS) and Oswestry dysfunction index (ODI) pre- and post-intervention. Furthermore, the sway area and velocity of the center of pressure (COP) were measured using a force platform. The cortical activities in 6 regions of interest during 4 tasks (standing with eyes open/closed on a stable/unstable plane) were recorded by functional near-infrared spectroscopy (fNIRS) pre- and post-intervention. The repeated measure ANOVA was applied for statistical analysis. Spearman's correlation was used to determine the relationships between variables.

RESULTS

After the intervention, the rPMS group showed decreased pain intensity (p = 0.001) and sway area (unstable eyes-closed task) (p = 0.046) compared to the sham-rPMS group. Additionally, the rPMS group exhibited increased activation in left primary motor cortex (M1) (p = 0.042) and reduced in left supplementary motor area (SMA) (p = 0.045), whereas the sham-rPMS group showed no significant changes. The increased activation of left M1 was negatively correlated to the reduction of pain intensity (r = - 0.537, p = 0.018) and sway area (r = - 0.500, p = 0.029) under the static balancing task. Furthermore, there was a positive correlation between sway velocity and VAS (r = 0.451, p = 0.046) post-rPMS intervention.

CONCLUSION

Repetitive peripheral magnetic stimulation combined with core muscle training demonstrated better analgesic effects and postural control improvements, compared to sham-stimulation. This may be attributed to the increased activation of the left primary motor cortex.

CLINICAL TRIAL REGISTRATION

The trial was registered on ClinicalTrials.gov (ChiCTR2300070943).

Synergistic efficacy of repetitive peripheral magnetic stimulation on central intermittent theta burst stimulation for upper limb function in patients with stroke: a double-blinded, randomized controlled trial

BACKGROUND

Non-invasive techniques such as central intermittent theta burst stimulation (iTBS) and repetitive peripheral magnetic stimulation (rPMS) have shown promise in improving motor function for patients with stroke. However, the combined efficacy of rPMS and central iTBS has not been extensively studied. This randomized controlled trial aimed to investigate the synergistic effects of rPMS and central iTBS in patients with stroke.

METHOD

In this study, 28 stroke patients were randomly allocated to receive either 1200 pulses of real or sham rPMS on the radial nerve of the affected limb, followed by 1200 pulses of central iTBS on the ipsilesional hemisphere. The patients received the intervention for 10 sessions over two weeks. The primary outcome measures were the Fugl-Meyer Assessment-Upper Extremity (FMA-UE) and the Action Research Arm Test (ARAT). Secondary outcomes for activities and participation included the Functional Independence Measure-Selfcare (FIM-Selfcare) and the Stroke Impact Scale (SIS). The outcome measures were assessed before and after the intervention.

RESULTS

Both groups showed significant improvement in FMA-UE and FIM-Selfcare after the intervention (p < 0.05). Only the rPMS + iTBS group had significant improvement in ARAT-Grasp and SIS-Strength and activity of daily living (p < 0.05). However, the change scores in all outcome measures did not differ between two groups.

CONCLUSIONS

Overall, the study's findings suggest that rPMS may have a synergistic effect on central iTBS to improve grasp function and participation. In conclusion, these findings highlight the potential of rPMS as an adjuvant therapy for central iTBS in stroke rehabilitation. Further large-scale studies are needed to fully explore the synergistic effects of rPMS on central iTBS.

TRIAL REGISTRATION

This trial was registered under ClinicalTrials.gov ID No.NCT04265365, retrospectively registered, on February 11, 2020.

Sensory Stimulation of the Triceps Surae Muscle Complex Modulates Spinal Reflex Responses-A Comparison between Tapotement Massage and Repetitive Peripheral Magnetic Stimulation (rPMS)

BACKGROUND

The reduction of muscular hypertonia is important in the treatment of various diseases or rehabilitation. This study aims to test the efficacy of a 5 Hz mechanical muscle stimulation (tapotement massage) in comparison to a 5 Hz repetitive peripheral magnetic stimulation (rPMS) on the neuromuscular reflex response.

METHODS

In a randomized control trial, 15 healthy volunteers were administered with either 5 Hz rPMS, tapotement massage, or rPMS sham stimulation. The posterior tibial nerve was stimulated with rPMS and sham stimulation. The Achilles tendon was exposed to a mechanically applied high-amplitude 5 Hz repetitive tendon tapotement massage (rTTM). The tendon reflex (TR) was measured for the spinal response of the soleus muscle.

RESULTS

After rPMS, there was a reduction of the TR response (-9.8%, p ≤ 0.034) with no significant changes after sham stimulation. Likewise, TR decreased significantly (-17.4%, p ≤ 0.002) after Achilles tendon tapotement intervention.

CONCLUSIONS

These findings support the hypothesis that both afferent 5 Hz sensory stimulations contributed to a modulation within the spinal and/or supraspinal circuits, which resulted in a reduction of the spinal reflex excitability. The effects could be beneficial for patients with muscle hypertonia and could improve the functional results of rehabilitation programs.

Functional Repetitive Neuromuscular Magnetic Stimulation (frNMS) Targeting the Tibialis Anterior Muscle in Children with Upper Motor Neuron Syndrome: A Feasibility Study

Non-invasive neurostimulation as an adjunctive intervention to task-specific motor training is an approach to foster motor performance in patients affected by upper motor neuron syndrome (UMNS). Here, we present first-line data of repetitive neuromuscular magnetic stimulation (rNMS) in combination with personalized task-specific physical exercises targeting the tibialis anterior muscle to improve ankle dorsiflexion (functional rNMS (frNMS)). The main objective of this pilot study was to assess the feasibility in terms of adherence to frNMS, safety and practicability of frNMS, and satisfaction with frNMS. First, during 10 training sessions, only physical exercises were performed (study period (SP) A). After a 1 week break, frNMS was delivered during 10 sessions (SPC). Twelve children affected by UMNS (mean age 8.9 ± 1.6 years) adhered to 93% (SPA) and 94% (SPC) of the sessions, and omittance was not related to the intervention itself in any case. frNMS was safe (no AEs reported in 88% of sessions, no AE-related discontinuation). The practicability of and satisfaction with frNMS were high. Patient/caregiver-reported outcomes revealed meaningful benefits on the individual level. The strength of the ankle dorsiflexors (MRC score) clinically meaningfully increased in four participants as spasticity of ankle plantar flexors (Tardieu scores) decreased in four participants after SPC. frNMS was experienced as a feasible intervention for children affected by UMNS. Together with the beneficial effects achieved on the individual level in some participants, this first study supports further real-world, large-scale, sham-controlled investigations to investigate the specific effects and distinct mechanisms of action of frNMS.

Addressing gross motor function by functional repetitive neuromuscular magnetic stimulation targeting to the gluteal muscles in children with bilateral spastic cerebral palsy: benefits of functional repetitive neuromuscular magnetic stimulation targeting the gluteal muscles

Background

Impaired selective motor control, weakness and spasticity represent the key characteristics of motor disability in the context of bilateral spastic cerebral palsy. Independent walking ability is an important goal and training of the gluteal muscles can improve endurance and gait stability. Combining conventional physical excercises with a neuromodulatory, non-invasive technique like repetitive neuromuscular magnetic stimulation probably enhances effects of the treatment. This prospective study aimed to assess the clinical effects of repetitive neuromuscular magnetic stimulation in combination with a personalized functional physical training offered to children and adolescents with bilateral spastic cerebral palsy.

Methods

Eight participants Gross Motor Function Classification System level II and III (10.4 ± 2y5m; 50% Gross Motor Function Classification System level II) received a personalized intervention applying functional repetitive neuromuscular magnetic stimulation (12 sessions within 3 weeks; 12,600 total stimuli during each session). At baseline and follow up the following assessments were performed: 10-m-walking-test, 6-min-walking-test, GMFM-66. Six weeks after the end of treatment the patient-reported outcome measure Gait Outcome Assessment List was completed.

Results

GMFM-66 total score improved by 1.4% (p = 0.002), as did scoring in domain D for standing (1.9%, p = 0.109) and domain E for walking, jumping and running (2.6%, p = 0.021). Gait speed or distance walked during 6 min did not improve from baseline to follow up. Patient-reported outcome showed improvement in 4 patients in altogether 14 ratings. Caregiver-reported outcome reported benefits in 3 participants in altogether 10 ratings.

Conclusion

Repetitive neuromuscular magnetic stimulation promises to be a meaningful, non-invasive treatment approach for children and adolescents with bilateral spastic cerebral palsy that could be offered in a resource-efficient manner to a broad number of patients. To further investigate the promising effects of repetitive neuromuscular magnetic stimulation and its mechanisms of action, larger-scaled, controlled trials are needed as well as comprehensive neurophysiological investigations.

The effects of combined high-frequency repetitive transcranial magnetic stimulation and cervical nerve root magnetic stimulation on upper extremity motor recovery following stroke

Introduction

Upper limb motor impairments after stroke cause patients partial or total loss of the capability of performing daily living, working, and social activities, which significantly affects the quality of life (QoL) of patients and brings a heavy burden to their families and society. As a non-invasive neuromodulation technique, transcranial magnetic stimulation (TMS) can act not only on the cerebral cortex, but also on peripheral nerves, nerve roots, and muscle tissues. Previous studies have shown that magnetic stimulation on the cerebral cortex and peripheral tissues has a positive effect on the recovery of upper limb motor function after stroke, however, few studies have reported the combination of the two.

Objective

This study was to investigate whether high frequency repetitive transcranial magnetic stimulation (HF-rTMS) combined with cervical nerve root magnetic stimulation more effectively ameliorates upper limb motor function in stroke patients. We hypothesized that the combination of the two can achieve a synergistic effect and further promotes functional recovery.

Methods

Sixty patients with stroke were randomly divided into four groups and received real or sham rTMS stimulation and cervical nerve root magnetic stimulation consecutively before other therapies, once daily over five fractions per week for a total of 15 times. We evaluated the upper limb motor function and activities of daily living of the patients at the time of pre-treatment, post-treatment, and 3-month follow up.

Results

All patients completed study procedures without any adverse effects. The upper limb motor function and activities of daily living improved in patients of each group were improved after treatment (post 1) and 3 months after treatment (post 2). Combination treatment was significantly better than single treatments alone or sham.

Conclusion

Both rTMS and cervical nerve root magnetic stimulation effectively promoted upper limb motor recovery in patients with stroke. The protocol combining the two is more beneficial for motor improvement and patients can easily tolerate it.

Clinical trial registration

https://www.chictr.org.cn/, identifier ChiCTR2100048558.

Repetitive peripheral magnetic stimulation for impairment and disability in people after stroke

BACKGROUND

Repetitive peripheral magnetic stimulation (rPMS) is a non-invasive treatment method that can penetrate to deeper structures with painless stimulation to improve motor function in people with physical impairment due to brain or nerve disorders. rPMS for people after stroke has proved to be a feasible approach to improving activities of daily living and functional ability. However, the effectiveness and safety of this intervention for people after stroke remain uncertain. This is an update of the review published in 2019.

OBJECTIVES

To assess the effects of rPMS for improving activities of daily living and functional ability in people after stroke.

SEARCH METHODS

We searched the Cochrane Stroke Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL), in the Cochrane Library; MEDLINE; Embase; the Cumulative Index to Nursing and Allied Health Literature (CINAHL); PsycINFO; the Allied and Complementary Medicine Database (AMED); OTseeker: Occupational Therapy Systematic Evaluation of Evidence; the Physiotherapy Evidence Database (PEDro); Ichushi-Web; and six ongoing trial registries on 5 October 2021. We screened reference lists and contacted experts in the field. We placed no restrictions on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) conducted to assess the therapeutic effect of rPMS for people after stroke. The following comparisons were eligible for inclusion: 1) active rPMS only compared with 'sham' rPMS (a very weak form of stimulation or a sound only); 2) active rPMS only compared with no intervention; 3) active rPMS plus rehabilitation compared with sham rPMS plus rehabilitation; and 4) active rPMS plus rehabilitation compared with rehabilitation only.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion in the review. The same review authors assessed methods and risk of bias, undertook data extraction, and evaluated the certainty of the evidence using the GRADE approach. We contacted trial authors to request unpublished information if necessary. Any disagreements were resolved through discussion.

MAIN RESULTS

We included four trials (three parallel-group RCTs and one cross-over trial) involving a total of 139 participants. This result was unchanged from the review published in 2019. Blinding of participants and physicians was well reported in three trials, with no information on whether personnel were blinded in one trial. We judged the overall risk of bias across trials as low. Only two trials (with 63 and 18 participants, respectively) provided sufficient information to be included in the meta-analysis. We found no clear effect of rPMS on activities of daily living at the end of treatment (mean difference (MD) -3.00, 95% confidence interval (CI) -16.35 to 10.35; P = 0.66; 1 trial; 63 participants; low-certainty evidence) and at the end of follow-up (MD -2.00, 95% CI -14.86 to 10.86; P = 0.76; 1 trial; 63 participants; low-certainty evidence) when comparing rPMS plus rehabilitation versus sham rPMS plus rehabilitation. We found no statistical difference in improvement of upper limb function at the end of treatment (MD 2.00, 95% CI -4.91 to 8.91; P = 0.57; 1 trial; 63 participants; low-certainty evidence) and at the end of follow-up (MD 4.00, 95% CI -2.92 to 10.92; P = 0.26; 1 trial; 63 participants; low-certainty evidence) when comparing rPMS plus rehabilitation versus sham rPMS plus rehabilitation. We observed a decrease in spasticity of the elbow at the end of follow-up (MD -0.41, 95% CI -0.89 to 0.07; 1 trial; 63 participants; low-certainty evidence) when comparing rPMS plus rehabilitation versus sham rPMS plus rehabilitation. In terms of muscle strength, rPMS treatment was not associated with improved muscle strength of the ankle dorsiflexors at the end of treatment (MD 3.00, 95% CI -2.44 to 8.44; P = 0.28; 1 trial; 18 participants; low-certainty evidence) when compared with sham rPMS. No studies provided information on lower limb function or adverse events, including death. Based on the GRADE approach, we judged the certainty of evidence related to the primary outcome as low, owing to the small sample size of the studies.

AUTHORS' CONCLUSIONS

There is insufficient evidence to permit the drawing of any conclusions about routine use of rPMS for people after stroke. Additional trials with large sample sizes are needed to provide robust evidence for rPMS after stroke.

The Facial Skin Blood Flow Change of Stroke Patients with Facial Paralysis after Peripheral Magnetic Stimulation: A Pilot Study

Background: Facial paralysis (FP) is a common symptom after stroke, which influences the quality of life and prognosis of patients. Recently, peripheral magnetic stimulation (PMS) shows potential effects on peripheral and central nervous system damage. However, the effect of PMS on FP after stroke is still unclear. Methods: In this study, we applied PMS on the facial nerve of nine stroke patients with FP. At the same time, laser speckle contrast imaging (LSCI) was used to explore the facial skin blood flow (SkBF) in 19 healthy subjects and nine stroke patients with FP before and after the PMS intervention. The whole face was divided into 14 regions to compare the SkBF in different sub-areas. Results: In baseline SkBF, we found that there were no significant differences in the SkBF between the left and right faces in the healthy subjects. However, there was a significant difference in the SkBF between the affected and unaffected faces in Region 7 (Chin area, p = 0.046). In the following five minutes after the PMS intervention (Pre_0–5 min), the SkBF increased in Region 5 (p = 0.014) and Region 7 (p = 0.046) and there was an increasing trend in Region 3 (p = 0.088) and Region 6 (p = 0.069). In the five to ten minutes after the intervention (Post_6–10 min), the SkBF increased in Region 5 (p = 0.009), Region 6 (p = 0.021) and Region 7 (p = 0.023) and there was an increasing trend in Region 3 (p = 0.080) and left and right whole face (p = 0.051). Conclusions: These pilot results indicate that PMS intervention could increase facial skin blood flow in stroke patients with FP. A further randomized controlled trial can be performed to explore its possible clinical efficacy.

Effect of High-Frequency Repetitive Peripheral Magnetic Stimulation on Motor Performance in Intracerebral Haemorrhage: A Clinical Trial

OBJECTIVES

The aim of the randomized, double-blind, sham-controlled trial was to explore the efficacy and safety of HF-rPMS synchronosly applied to the axilla (stimulating the brachial plexus) and the popliteal fossa (stimulating the tibial nerve and common peroneal nerve) in patients with intracerebral hemorrhage on rehabilitation of motor functions.

MATERIALS AND METHODS

Patients with intracerebral haemorrhage in the early period were recruited and randomly assigned to the HF-rPMS group or the sham rPMS group. The two synchrous coils of magnetic stimulation in the two groups were respectively applied to the axilla and the popliteal fossa of the affected limb. But the sham group received the ineffective rPMS and only heard the sound as occured in the HF-rPMS group. Clinical outcomes included the change of Fugl-Meyer Assessment (FMA) scale and Medical Research Council (MRC) scale before and after HF-rPMS.

RESULTS

Of 76 eligible patients, 30 were included and only 26 patients completed this study. The diferences on the improvement of the upper extremity FMA (P=0.012), the lower extremity FMA (P=0.001), the proximal MRC of upper extremity (p = 0.043), the proximal MRC of lower extremity (p= 0.004) and the distal MRC scores of lower extremity (p= 0.008) between the the HF-rPMS group and sham rPMS group were statistically signifcant.

CONCLUSIONS

Synchrous HF-rPMS intervention at the axilla and the popliteal fossa significantly improved motor function and proximal muscle strength of upper and lower limb of patients in acute or early subacute phase of intracerebral hemorrhage.

Implicit Body Representation of the Hand Enlarged by Repetitive Peripheral Magnetic Stimulation within the Boundary of a Real Hand

Deafferentation induced by local anesthesia causes a larger perceived area than the real area of the mouth, which, in the perspective of body representation, belongs to implicit body representation. In this study, we applied repetitive peripheral magnetic stimulation (rPMS) on the motor branch of the radial nerve of participants’ non-dominant-side forearm to induce extension movements of wrist and fingers. This intervention was supposed to increase proprioception to the brain and had an enlargement effect on implicit body representation of the hand in our hypothesis. A total of 39 participants were randomly allocated to the real rPMS group (n = 19) or the sham rPMS group (n = 20). Implicit representation of the hand was measured by a simplified paradigm based on the proposal of Longo and Haggard that depicted perceived locations of fingertips and metacarpophalangeal joints of participants’ occluded hand, in which they showed that implicit body representation of the hand was smaller than the real hand. We compare the main effect of real rPMS vs. sham rPMS and its interaction effect with time by setting four timepoints—before stimulation, right after stimulation, 10 min after stimulation and 20 min after stimulation—to demonstrate the possible short-lasting effect. Results showed that real rPMS had a short-lasting enlargement effect on implicit representation of the hand in general, which was significant especially on the ulnar side of fingers. What is more, the enlarged implicit body representation of the hand was still within the boundary of a real hand, which might indicate the identification role of a real body part.

Effects of Repetitive Peripheral Magnetic Stimulation through Hand Splint Materials on Induced Movement and Corticospinal Excitability in Healthy Participants

Repetitive peripheral magnetic stimulation (rPMS) is a non-invasive neuromodulation technique. Magnetic fields induced by rPMS pass through almost all materials, and it has clinical applications for neurorehabilitation. However, the effects of rPMS through clothing and orthosis on induced movement and corticospinal excitability remain unclear. The aim of this study was to determine whether rPMS induces movement and enhances corticospinal excitability through hand splint materials. rPMS was applied directly to the skin (L0) and through one (L1) or two (L2) layers of splint material in 14 healthy participants at 25-Hz, 2-s train per 6 s for a total of 20 min. rPMS was delivered to the forearm with the stimulus intensity set to 1.5-times the train intensity-induced muscle contractions under the L0 condition. We recorded induced wrist movements during rPMS and motor-evoked potentials of the extensor carpi radialis pre- and post-application. The results showed that rPMS induced wrist movements in L0 and L1, and it facilitated corticospinal excitability in L0 but not in L1 and L2. This suggests that rPMS can make electromagnetic induction on periphery even when applied over clothing and orthosis and demonstrates the potential clinical applications of this technique for neurorehabilitation.

Time course changes in corticospinal excitability during repetitive peripheral magnetic stimulation combined with motor imagery

Repetitive peripheral magnetic stimulation (rPMS) induces proprioceptive afferents and facilitates corticospinal excitability. Short-term sessions of rPMS combined with motor imagery (MI) enhance corticospinal excitability more than rPMS alone. However, it is not clear how long the intervention of rPMS combined with MI would be needed to facilitate corticospinal excitability. Therefore, we investigated the time course change in corticospinal excitability during the combination of rPMS and MI. Thirteen healthy volunteers participated in a 20-min intervention under the following three experimental conditions on different days: rPMS, MI, and rPMS combined with MI (rPMS + MI). In the rPMS and rPMS + MI, the participants were delivered rPMS, which was 25 Hz, 2 s/train at 1.5 × of the train intensity induced muscle contractions, through the wrist extensor muscles. In the MI and rPMS + MI, the participants repeatedly imagined wrist movements for 2 s. Motor evoked potentials (MEPs) were recorded from the extensor carpi radialis (ECR) and flexor carpi radialis (FCR) muscles every 5 min for each condition. The MEP amplitudes of the ECR after > 10 min of intermittent rPMS combined with MI were greater than baseline. The MEP amplitude of the ECR in rPMS + MI was greater than that in rPMS condition after 20 min of intervention. The present results suggest that over 10 min of intermittent rPMS combined with MI facilitates corticospinal excitability, and that the effect of rPMS combined with MI on corticospinal excitability might be greater than that of rPMS alone.

Effect of repetitive peripheral magnetic stimulation combined with motor imagery on the corticospinal excitability of antagonist muscles

OBJECTIVE

Repetitive peripheral magnetic stimulation (rPMS) combined with motor imagery facilitates the corticospinal excitability of the agonist muscles. However, the effects of rPMS combined with motor imagery on the corticospinal excitability of the antagonist muscles are unclear. This is an important aspect for applying rPMS in neurorehabilitation for sensorimotor dysfunction. Therefore, we investigated the real-time changes of corticospinal excitability of antagonist muscles during rPMS combined with motor imagery.

METHODS

Fourteen healthy volunteers underwent four different experimental conditions: rest, rPMS, motor imagery, and rPMS combined with motor imagery (rPMS + motor imagery). In the rPMS and rPMS + motor imagery conditions, rPMS (25 Hz, 1600 ms/train, 1.5× of the motor threshold) was delivered to the dorsal side of the forearm. In motor imagery and rPMS + motor imagery, the participant imagined wrist extension movements. Transcranial magnetic stimulation was delivered to record motor-evoked potentials of the antagonist muscle during experimental interventions.

RESULTS

The motor-evoked potential (normalized by rest condition) values indicated no difference between rPMS, motor imagery, and rPMS + motor imagery.

CONCLUSION

These results suggest that rPMS combined with motor imagery has no effect on the corticospinal excitability of the antagonist muscles and highlight the importance of investigating the effects of rPMS combined with motor imagery at the spinal level.

Modulation of the Corticomotor Excitability by Repetitive Peripheral Magnetic Stimulation on the Median Nerve in Healthy Subjects

Objective: We aimed to examine the effects of repetitive peripheral nerve magnetic stimulation (rPNMS) on the excitability of the contralateral motor cortex and motor function of the upper limb in healthy subjects.

Methods: Forty-six healthy subjects were randomly assigned to either a repetitive peripheral nerve magnetic stimulation group (n = 23) or a sham group (n = 23). The repetitive peripheral nerve magnetic stimulation group received stimulation using magnetic pulses at 20 Hz, which were applied on the median nerve of the non-dominant hand, whereas the sham group underwent the same protocol without the stimulation output. The primary outcome was contralateral transcranial magnetic stimulation (TMS)-induced corticomotor excitability for the abductor pollicis brevis of the stimulated hand in terms of resting motor threshold (rMT), the slope of recruitment curve, and peak amplitude of motor evoked potential (MEP), which were measured at baseline and immediately after each session. The secondary outcomes were motor hand function including dexterity and grip strength of the non-dominant hand assessed at baseline, immediately after stimulation, and 24 h post-stimulation.

Results: Compared with the sham stimulation, repetitive peripheral nerve magnetic stimulation increased the peak motor evoked potential amplitude immediately after the intervention. The repetitive peripheral nerve magnetic stimulation also increased the slope of the recruitment curve immediately after intervention and enhanced hand dexterity after 24 h. However, the between-group difference for the changes was not significant. The significant changes in hand dexterity and peak amplitude of motor evoked potential after repetitive peripheral nerve magnetic stimulation were associated with their baseline value.

Conclusions: Repetitive peripheral nerve magnetic stimulation may modulate the corticomotor excitability together with a possible lasting improvement in hand dexterity, indicating that it might be helpful for clinical rehabilitation.

Repetitive Peripheral Magnetic Stimulation of Wrist Extensors Enhances Cortical Excitability and Motor Performance in Healthy Individuals

Repetitive peripheral magnetic stimulation (rPMS) may improve motor function following central nervous system lesions, but the optimal parameters of rPMS to induce neural plasticity and mechanisms underlying its action remain unclear. We examined the effects of rPMS over wrist extensor muscles on neural plasticity and motor performance in 26 healthy volunteers. In separate experiments, the effects of rPMS on motor evoked potentials (MEPs), short-interval intracortical inhibition (SICI), intracortical facilitation (ICF), direct motor response (M-wave), Hoffmann-reflex, and ballistic wrist extension movements were assessed before and after rPMS. First, to examine the effects of stimulus frequency, rPMS was applied at 50, 25, and 10 Hz by setting a fixed total number of stimuli. A significant increase in MEPs of wrist extensors was observed following 50 and 25 Hz rPMS, but not 10 Hz rPMS. Next, we examined the time required to induce plasticity by increasing the number of stimuli, and found that at least 15 min of 50 and 25 Hz rPMS was required. Based on these parameters, lasting effects were evaluated following 15 min of 50 or 25 Hz rPMS. A significant increase in MEP was observed up to 60 min following 50 and 25 Hz rPMS; similarly, an attenuation of SICI and enhancement of ICF were also observed. The maximal M-wave and Hoffmann-reflex did not change, suggesting that the increase in MEP was due to plastic changes at the motor cortex. This was accompanied by increasing force and electromyograms during wrist ballistic extension movements following 50 and 25 Hz rPMS. These findings suggest that 15 min of rPMS with 25 Hz or more induces an increase in cortical excitability of the relevant area rather than altering the excitability of spinal circuits, and has the potential to improve motor output.

Electroencephalography Mu Rhythm Changes and Decreased Spasticity After Repetitive Peripheral Magnetic Stimulation in Patients Following Stroke

Background: Spasticity is common among patients with stroke. Repetitive peripheral magnetic stimulation (rPMS) is a painless and noninvasive therapy that is a promising approach to reducing spasticity. However, the central mechanism of this therapy remains unclear. Changes in cortical activity and decreased spasticity after rPMS intervention require further exploration. The aim of this study was to explore the electroencephalography (EEG) mu rhythm change and decrease in spasticity after rPMS intervention in patients with stroke. Materials and methods: A total of 32 patients with spasticity following stroke were recruited in this study and assigned to the rPMS group (n = 16) or sham group (n = 16). The modified Ashworth scale, modified Tardieu scale, and Fugl-Meyer assessment of the upper extremity were used to assess changes in upper limb spasticity and motor function. Before and after the rPMS intervention, EEG evaluation was performed to detect EEG mu rhythm changes in the brain. Results: After one session of rPMS intervention, spasticity was reduced in elbow flexors (p < 0.05) and wrist flexors (p < 0.05). Upper limb motor function measured according to the Fugl-Meyer assessment was improved (p < 0.05). In the rPMS group, the power of event-related desynchronization decreased in the mu rhythm band (8-12 Hz) in the contralesional hemisphere (p < 0.05). Conclusions: The results indicate that rPMS intervention reduced spasticity. Cortical activity changes may suggest this favorable change in terms of its neurological effects on the central nervous system.

Repetitive peripheral magnetic stimulation combined with intensive physical therapy for gait disturbance after hemorrhagic stroke: an open-label case series

In this pilot study, we aimed to determine the safety and feasibility of a 15-day protocol consisting of in-hospital repetitive peripheral magnetic stimulation (rPMS) combined with intensive physical therapy for the recovery of the gait disturbance in chronic stroke patients with lower limb hemiparesis. Seven hemorrhagic stroke patients with lower limb hemiparesis and gait disturbance (age: 50-78; time from onset of stroke: 7-107 months) were enrolled. rPMS was applied to the muscles of the paretic lower limb with a parabolic coil. A train of stimuli at a frequency of 20 Hz was applied for 3 s followed by a 27-s rest interval. Therapy with rPMS was performed with eighty such trains of stimuli (total 4800 pulses). Following rPMS therapy, 120 min of physical therapy was administrated daily. Each patient received this combination treatment over fifteen consecutive days, with the walking function of all participants assessed before and after the intervention. The proposed treatment protocol resulted in significant improvements in the walking speed, ambulation ability, and balance ability, but showed no significant effects on the endurance capacity, step length, and spasticity. No rPMS-related side effects were noted. Our protocol consisting of rPMS and intensive physical therapy appears well tolerated and feasible for therapy in hemorrhagic stroke patients with gait disturbance. Further large-scale studies are required to confirm its efficacy.

Dose-response of rPMS for upper Limb hemiparesis after stroke

INTRODUCTION

Repetitive peripheral magnetic stimulation (rPMS) therapy is an innovative and minimally invasive neurorehabilitative technique and has been shown to facilitate neural plasticity. However, there is at present no research that clarifies the dose-response of rPMS therapy on the recovery of upper limb hemiparesis after stroke. This trial aims to clarify the dose-response of rPMS therapy combined with intensive occupational therapy (OT) for chronic stroke patients with moderate to severe upper limb hemiparesis.

METHODS AND ANALYSIS

This multicenter, prospective, assessor-blinded, randomized controlled study with 3 parallel groups will be conducted from January 20, 2020 to September 30, 2022. Fifty patients will be randomly assigned in a ratio of 1:2:2 to the control group, the group receiving daily 2400 pulses of rPMS, or the group receiving daily 4800 pulses of rPMS, respectively. From the day after admission (Day 1), rPMS therapy and intensive OT will be initiated. The primary outcome is the change in the motor function of the affected upper extremity (Fugl-Meyer Assessment) between the time of admission (Day 0) and the day after 2 weeks of treatment (Day 14). Secondary outcomes will include the changes in spasticity, active range of motion, motor evoked potential, and activity of daily living.

ETHICS AND DISSEMINATION

The study was approved by the Jikei University Certified Review Board for all institutions (reference number: JKI19-020). Results of the primary and secondary outcomes will be published in a peer-reviewed journal and presented at international congresses. The results will also be disseminated to patients.

TRIAL REGISTRATION NUMBER

jRCTs032190191.

Repetitive peripheral magnetic stimulation for impairment and disability in people after stroke

BACKGROUND

Repetitive peripheral magnetic stimulation (rPMS) is a non-invasive treatment method that can penetrate to deeper structures with painless stimulation to improve motor function in people with physical impairment due to brain or nerve disorders. rPMS for people after stroke has proved to be a feasible approach to improving activities of daily living and functional ability. However, the effectiveness and safety of this intervention for people after stroke currently remain uncertain. This is an update of the review published in 2017.

OBJECTIVES

To assess the effects of rPMS in improving activities of daily living and functional ability in people after stroke.

SEARCH METHODS

On 7 January 2019, we searched the Cochrane Stroke Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL), in the Cochrane Library; MEDLINE; Embase; the Cumulative Index to Nursing and Allied Health Literature (CINAHL); PsycINFO; the Allied and Complementary Medicine Database (AMED); Occupational Therapy Systematic Evaluation of Evidence (OTseeker); the Physiotherapy Evidence Database (PEDro); ICHUSHI Web; and six ongoing trial registries. We screened reference lists, and we contacted experts in the field. We placed no restrictions on the language or date of publication when searching electronic databases.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) conducted to assess the therapeutic effect of rPMS for people after stroke. Comparisons eligible for inclusion were (1) active rPMS only compared with 'sham' rPMS (a very weak form of stimulation or a sound only); (2) active rPMS only compared with no intervention; (3) active rPMS plus rehabilitation compared with sham rPMS plus rehabilitation; and (4) active rPMS plus rehabilitation compared with rehabilitation only.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion. The same review authors assessed methods and risk of bias, undertook data extraction, and used the GRADE approach to assess the quality of evidence. We contacted trial authors to request unpublished information if necessary. We resolved all disagreements through discussion.

MAIN RESULTS

We included four trials (three RCTs and one cross-over trial) involving 139 participants. Blinding of participants and physicians was well reported within all trials. We judged the overall risk of bias across trials as low. Only two trials (with 63 and 18 participants, respectively) provided sufficient information to be included in the meta-analysis. We found no clear effect of rPMS on activities of daily living at the end of treatment (mean difference (MD) -3.00, 95% confidence interval (CI) -16.35 to 10.35; P = 0.66; 1 trial; 63 participants; low-quality evidence) and at the end of follow-up (MD -2.00, 95% CI -14.86 to 10.86; P = 0.76; 1 trial; 63 participants; low-quality evidence) when comparing rPMS plus rehabilitation versus sham plus rehabilitation. We found no statistical difference in improvement of upper limb function at the end of treatment (MD 2.00, 95% CI -4.91 to 8.91; P = 0.57; 1 trial; 63 participants; low-quality evidence) and at the end of follow-up (MD 4.00, 95% CI -2.92 to 10.92; P = 0.26; 1 trial; 63 participants; low-quality evidence) when comparing rPMS plus rehabilitation versus sham plus rehabilitation. We observed a significant decrease in spasticity of the elbow at the end of follow-up (MD -0.48, 95% CI -0.93 to -0.03; P = 0.03; 1 trial; 63 participants; low-quality evidence) when comparing rPMS plus rehabilitation versus sham plus rehabilitation. In terms of muscle strength, rPMS treatment was not associated with improved muscle strength of the ankle dorsiflexors at the end of treatment (MD 3.00, 95% CI -2.44 to 8.44; P = 0.28; 1 trial; 18 participants; low-quality evidence) when compared with sham rPMS. No studies provided information on lower limb function or adverse events, including death. Based on the GRADE approach, we judged the quality of evidence related to the primary outcome as low, owing to the small sample size of the studies.

AUTHORS' CONCLUSIONS

Available trials provided insufficient evidence to permit any conclusions about routine use of rPMS for people after stroke. Additional trials with large sample sizes are needed to provide robust evidence for rPMS after stroke.

The effects of mechanical tactile stimulation on corticospinal excitability and motor function depend on pin protrusion patterns

Somatosensory stimulation modulates corticospinal excitability. Mechanical tactile stimulation (MS) activates cortical activity depending on tactile stimulation patterns. In this study, we examined whether the effects of mechanical tactile stimulation on corticospinal excitability and motor function depend on different pin protrusions patterns. This single-blind study included 18 healthy subjects. Two types of MS interventions were used: repetitive global stimulus (RGS) intervention was used to stimulate the finger by using 24 pins installed on a finger pad, and sequential stepwise displacement stimulus (SSDS) intervention was used to stimulate the finger by moving a row of 6 pins between the left and right sides on the finger pad. MS interventions were applied to the right index finger for 20 min (stim on/stim off, 1 s/5 s) at a frequency of 20 Hz. After RGS intervention, motor evoked potentials (MEPs) by transcranial magnetic stimulation were observed to be significantly smaller than pre-intervention MEPs; however, motor function using the grooved pegboard task remained unchanged. After SSDS intervention, MEPs were significantly larger and motor function significantly improved compared with pre-intervention values. Our results demonstrated that MS intervention can modulate corticospinal excitability and motor function and that the effects of MS intervention depend on MS intervention patterns.

Coupling Magnetically Induced Electric Fields to Neurons: Longitudinal and Transverse Activation

We present a theory and computational models to couple the electric field induced by magnetic stimulation to neuronal membranes. Based on the characteristics of magnetically induced electric fields and the modified cable equation that we developed previously, quasipotentials are derived as a simple and accurate approximation for coupling of the electric fields to neurons. The conventional and modified cable equations are used to simulate magnetic stimulation of long peripheral nerves by circular and figure-8 coils. Activation thresholds are obtained over a range of lateral and vertical coil positions for two nonlinear membrane models representing unmyelinated and myelinated straight axons and also for undulating myelinated axons. For unmyelinated straight axons, the thresholds obtained with the modified cable equation are significantly lower due to transverse polarization, and the spatial distributions of thresholds as a function of coil position differ significantly from predictions by the activating function. However, the activation thresholds of unmyelinated axons obtained with either cable equation are very high and beyond the output capabilities of conventional magnetic stimulators. For myelinated axons, threshold values are similar for both cable equations and within the range of magnetic stimulators. Whereas the transverse field contributes negligibly to the activation thresholds of myelinated fibers, axonal undulation can significantly increase or decrease thresholds depending on coil position. The analysis provides a rigorous theoretical foundation and implementation methods for the use of the cable equation to model neuronal response to magnetically induced electric fields. Experimentally observed stimulation with the electric fields perpendicular to the nerve trunk cannot be explained by transverse polarization and is likely due to nerve fiber undulation and other geometrical inhomogeneities.

Differential Effects of Sustained Manual Pressure Stimulation According to Site of Action

Sustained pressure stimulation of the body surface has been used in several physiotherapeutic techniques, such as reflex locomotion therapy. Clinical observations of global motor responses and subsequent motor behavioral changes after stimulation in certain sites suggest modulation of central sensorimotor control, however, the neuroanatomical correlates remain undescribed. We hypothesized that different body sites would specifically influence the sensorimotor system during the stimulation. We tested the hypothesis using functional magnetic resonance imaging (fMRI) in thirty healthy volunteers (mean age 24.2) scanned twice during intermittent manual pressure stimulation, once at the right lateral heel according to reflex locomotion therapy, and once at the right lateral ankle (control site). A flexible modeling approach with finite impulse response basis functions was employed since non-canonical hemodynamic response was expected. Subsequently, a clustering algorithm was used to separate areas with differential timecourses. Stimulation at both sites induced responses throughout the sensorimotor system that could be mostly separated into two anti-correlated subsystems with transient positive or negative signal change and rapid adaptation, although in heel stimulation, insulo-opercular cortices and pons showed sustained activation. In direct voxel-wise comparison, heel stimulation was associated with significantly higher activation levels in the contralateral primary motor cortex and decreased activation in the posterior parietal cortex. Thus, we demonstrate that the manual pressure stimulation affects multiple brain structures involved in motor control and the choice of stimulation site impacts the shape and amplitude of the blood oxygenation level-dependent response. We further discuss the relationship between the affected structures and behavioral changes after reflex locomotion therapy.

Does cerebellar non-invasive brain stimulation affect corticospinal excitability in healthy individuals? A systematic review of literature and meta-analysis

Numerous studies have indicated that non-invasive brain stimulation (NIBS) of the cerebellum could modulate corticospinal excitability (CSE) in young healthy individuals. However, there is no systematic review and meta-analysis that clarifies the effects of cerebellar NIBS on CSE. The aim of this study was to provide a meta-analytic summary of the effects of cerebellar NIBS on CSE. Seven search engines were used to identify any trial evaluating CSE before and after one session of cerebellar NIBS in healthy individuals up to June 2018. Twenty-six studies investigating the corticospinal responses following cerebellar NIBS were included. Meta-analysis was used to pool the findings from included studies. Effects were expressed as mean differences (MD) and the standard deviation (SD). Risk of bias was assessed with the Cochrane tool. Meta-analysis found that paired associative stimulation (PAS) with 2 ms interval, a combination of PAS with 21.5 ms interval and anodal transcranial direct current stimulation, and repetitive transcranial magnetic stimulation with a frequency of < 5 Hz increase CSE (P _PAS2 < 0.00001, P _{PAS21.5 +a-tDCS} = 0.02, P _rTMS = 0.04). However, continuous theta burst stimulation, a combination of PAS with 25 ms interval and anodal transcranial direct current stimulation, and PAS with a 6 ms interval decreased CSE (P _PAS6 < 0.00001, P _cTBS < 0.00001, P _{PAS25 +a-tDCS} = 0.003). The results of this review show that cerebellar NIBS techniques are a promising tool for increasing CSE.

Paired Associative Electroacupuncture and Transcranial Magnetic Stimulation in Humans

Pairing transcutaneous electric nerve stimulation (TENS) and transcranial magnetic stimulation (TMS) with specific stimulus-intervals induces associative motor plasticity at the primary motor cortex (M1). Electroacupuncture (EA) is an established medical technique in the eastern countries. This study investigates whether EA paired with TMS induces distinct M1 motor plasticity. Fifteen healthy, right-handed subjects (aged 23.6 ± 2.0 years, eight women) were studied. Two-hundred and twenty-five pairs of TMS of the left M1 preceded by right EA at acupoint “Neiguan” [Pericardium 6 (PC6), located 2 decimeters proximal from the wrist wrinkle] were respectively applied with the interstimulus interval (ISI) of individual somatosensory evoked potential (SSEP) N20 latency plus 2 ms (N20+2) and minus 5 ms (N20-5) with at least 1-week interval. The paired stimulation was delivered at a rate of 0.25 Hz. Sham TMS with a sham coil was adopted to examine the low-frequency EA influence on M1 in eleven subjects. M1 excitability was assessed by motor-evoked potential (MEP) recruitment curve with five TMS intensity levels, short-interval intracortical inhibition (SICI), intracortical facilitation (ICF) and cerebellar inhibition (CBI) at the abductor pollicis brevis (APB) muscle of the right hand before and after the EA-M1 paired associative stimulation (PAS). In addition, median nerve SSEPs and H-reflex were respectively measured to monitor somatosensory and spinal excitability. The MEP showed significantly facilitated after the sham EA-M1 PAS while tested with 80% of the TMS intensity producing on average 1 mV amplitude (i.e., MEP_{1 mV}) in the resting APB muscle. It was also facilitated while tested with 90% MEP_{1 mV} irrespective of the stimulation conditions. The SSEP showed a higher amplitude from the real EA-M1 PAS compared to that from the sham EA-M1 PAS. No significant change was found on SICI, ICF, CBI and H-reflex. Findings suggest that repetitive low frequency EA paired with real TMS did not induce spike-timing dependent motor plasticity but EA paired with sham TMS induced specific M1 excitability change. Complex sensory afferents with dispersed time locked to the sensorimotor cortical area could hamper instead of enhancing the induction of the spike-timing dependent plasticity (STDP) in M1.

Cortical and Subcortical Contributions to Neuroplasticity after Repetitive Transspinal Stimulation in Humans

The objectives of this study were to establish cortical and subcortical contributions to neuroplasticity induced by noninvasive repetitive transspinal stimulation in human subjects free of any neurological disorder. To meet our objectives, before and after 40 minutes of transspinal stimulation we established changes in tibialis anterior (TA) motor-evoked potentials (MEPs) in response to paired transcranial magnetic stimulation (TMS) pulses at interstimulus intervals (ISIs) consistent with I-wave periodicity. In order to establish to what extent similar actions are exerted at the spinal cord and motor axons, changes in soleus H-reflex and transspinal evoked potential (TEP) amplitude following transspinal and group Ia afferent conditioning stimulation, respectively, were established. After 40 min of transspinal stimulation, the TA MEP consecutive peaks of facilitation produced by paired TMS pulses were significantly decreased supporting for depression of I-waves. Additionally, the soleus H-reflex and ankle TEP depression following transspinal and group Ia afferent conditioning stimulation was potentiated at intervals when both responses interacted at the spinal cord and nerve axons. These findings support the notion that repetitive transspinal stimulation decreases corticocortical inputs onto corticospinal neurons and promotes a surround inhibition in the spinal cord and nerve axons. This novel method may be a suitable neuromodulation tool to alter excitability at cortical and subcortical levels in neurological disorders.

Effects of Repetitive Peripheral Magnetic Stimulation on Patients With Acute Low Back Pain: A Pilot Study

Objective

To investigate the effects of real repetitive peripheral magnetic stimulation (rPMS) treatment compared to sham rPMS treatment on pain reduction and functional recovery of patients with acute low back pain.

Methods

A total of 26 patients with acute low back pain were randomly allocated to the real rPMS group and the sham rPMS group. Subjects were then administered a total of 10 treatment sessions. Visual analogue scale (VAS) was assessed before and after each session. Oswestry Disability Index (ODI) and Roland-Morris Disability Questionnaire (RMDQ) were employed to assess functional recovery at baseline and after sessions 5 and 10.

Results

Real rPMS treatment showed significant pain reduction immediately after each session. Sustained and significant pain relief was observed after administering only one session in the real rPMS group. Significant functional improvement was observed in the real rPMS group compared to that in the sham rPMS group after sessions 5 and 10 based on ODI and after session 5 based on RMDQ.

Conclusion

Real rPMS treatment has immediate effect on pain reduction and sustained effect on pain relief for patients with acute low back pain compared to sham rPMS.

Effects of Repetitive Peripheral Magnetic Stimulation Over Vastus Lateralis in Patients After Hip Replacement Surgery

Objective

To investigate the effects of repetitive peripheral magnetic stimulation (rPMS) on the vastus lateralis (VL) in the early stage after hip replacement surgery.

Methods

Twenty-two patients who underwent hip replacement after proximal femur fracture were included in this study. After hip surgery, the experimental group was applied with 15 sessions of 10 Hz rPMS over the VL 5 times per week for 3 weeks, while the control group took sham stimulation. All patients were also given conventional physical therapy. The VL strength was measured with the root mean square (RMS) value of the VL with surface electromyography technique. The ratio of RMS values between fractured and unfractured legs and tandem stand test were used to assess standing balance. Usual gait speed was measured to evaluate gait function. Pain in two groups was assessed with visual analog scale (VAS).

Results

Both RMS value of the VL and the ratio of RMS values after rPMS were significantly improved (p<0.05). Also, tandem standing time and usual gait speed in rPMS group were dramatically increased (p<0.05). However, no significant difference in VAS was found between the two groups after 3 weeks.

Conclusion

rPMS on the VL improved muscle strength, standing balance and gait function in the early stage after hip surgery. Therefore, rPMS could be applied to patients who cannot take electrical stimulation due to pain and an unhealed wound.

Repetitive peripheral magnetic stimulation for activities of daily living and functional ability in people after stroke

BACKGROUND

Repetitive peripheral magnetic stimulation (rPMS) is a form of therapy that creates painless stimulation of deep muscle structures to improve motor function in people with physical impairment from brain or nerve disorders. Use of rPMS for people after stroke has been identified as a feasible approach to improve activities of daily living and functional ability. However, no systematic reviews have assessed the findings of available trials. The effect and safety of this intervention for people after stroke currently remain uncertain.

OBJECTIVES

To assess the effect of rPMS for improving activities of daily living and functional ability in people after stroke.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (August 2016), the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 8) in the Cochrane Library (August 2016), MEDLINE Ovid (November 2016), Embase Ovid (August 2016), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) in Ebsco (August 2016), PsycINFO Ovid (August 2016), the Allied and Complementary Medicine Database (AMED) Ovid (August 2016), Occupational Therapy Systematic Evaluation of Evidence (OTseeker) (August 2016), the Physiotherapy Evidence Database (PEDro) (October 2016), and ICHUSHI Web (October 2016). We also searched five ongoing trial registries, screened reference lists, and contacted experts in the field. We placed no restrictions on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) conducted to assess the therapeutic effect of rPMS for people after stroke. Comparisons eligible for inclusion were (1) active rPMS only compared with 'sham' rPMS (a very weak form of stimulation or a sound only); (2) active rPMS only compared with no intervention; (3) active rPMS plus rehabilitation compared with sham rPMS plus rehabilitation; and (4) active rPMS plus rehabilitation compared with rehabilitation only.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion. The same review authors assessed methods and risk of bias and extracted data. We contacted trial authors to ask for unpublished information if necessary. We resolved all disagreements through discussion.

MAIN RESULTS

We included three trials (two RCTs and one cross-over trial) involving 121 participants. Blinding of participants and physicians was well reported in all trials, and overall risk of bias was low. We found no clear effect of rPMS on activities of daily living at the end of treatment (mean difference (MD) -3.00, 95% confidence interval (CI) -16.35 to 10.35; low-quality evidence) and at the end of follow-up (MD -2.00, 95% CI -14.86 to 10.86; low-quality evidence). Investigators in one study with 63 participants observed no statistical difference in improvement of upper limb function at the end of treatment (MD 2.00, 95% CI -4.91 to 8.91) and at the end of follow-up (MD 4.00, 95% CI -2.92 to 10.92). One trial with 18 participants showed that rPMS treatment was not associated with improved muscle strength at the end of treatment (MD 3.00, 95% CI -2.44 to 8.44). Another study reported a significant decrease in spasticity of the elbow at the end of follow-up (MD -0.48, 95% CI -0.93 to -0.03). No studies provided information on lower limb function and death. Based on the GRADE approach, we judged the certainty of evidence related to the primary outcome as low owing to the small sample size of one study.

AUTHORS' CONCLUSIONS

Available trials provided inadequate evidence to permit any conclusions about routine use of rPMS for people after stroke. Additional trials with large sample sizes are needed to determine an appropriate rPMS protocol as well as long-term effects. We identified three ongoing trials and will include these trials in the next review update.

Modulation of the sensorimotor system by sustained manual pressure stimulation

In Vojta physiotherapy, also known as reflex locomotion therapy, prolonged peripheral pressure stimulation induces complex generalized involuntary motor responses and modifies subsequent behavior, but its neurobiological basis remains unknown. We hypothesized that the stimulation would induce sensorimotor activation changes in functional magnetic resonance imaging (fMRI) during sequential finger opposition. Thirty healthy volunteers (mean age 24.2) underwent two randomized fMRI sessions involving manual pressure stimulation applied either at the right lateral heel according to Vojta, or at the right lateral ankle (control site). Participants were scanned before and after the stimulation when performing auditory-paced sequential finger opposition with their right hand. Despite an extensive activation decrease following both stimulation paradigms, the stimulation of the heel specifically led to an increase in task-related activation in the predominantly contralateral pontomedullary reticular formation and bilateral posterior cerebellar hemisphere and vermis. Our findings suggest that sustained pressure stimulation of the foot is associated with differential short-term changes in hand motor task-related activation depending on the stimulation. This is the first evidence for brainstem modulation after peripheral pressure stimulation, suggesting that the after-effects of reflex locomotion physiotherapy involve a modulation of the pontomedullary reticular formation.

Magnetic stimulation at Neiguan (PC6) acupoint increases connections between cerebral cortex regions

Stimulation at specific acupoints can activate cortical regions in human subjects. Previous studies have mainly focused on a single brain region. However, the brain is a network and many brain regions participate in the same task. The study of a single brain region alone cannot clearly explain any brain-related issues. Therefore, for the present study, magnetic stimulation was used to stimulate the Neiguan (PC6) acupoint, and 32-channel electroencephalography data were recorded before and after stimulation. Brain functional networks were constructed based on electroencephalography data to determine the relationship between magnetic stimulation at the PC6 acupoint and cortical excitability. Results indicated that magnetic stimulation at the PC6 acupoint increased connections between cerebral cortex regions.