A Systematic Review and Meta-Analysis on the Use of Repetitive Transcranial Magnetic Stimulation for Spasticity Poststroke

Accepted Manuscript A Systematic Review and Meta-Analysis on the Use of Repetitive Transcranial Magnetic Stimulation for Spasticity Post Stroke A. McIntyre, M. Mirkowski, S. Thompson, A.M. Burhan, T. Miller, R. Teasell PII:

S1934-1482(17)31359-X

DOI:

10.1016/j.pmrj.2017.10.001

Reference:

PMRJ 1999

To appear in:

PM&R

Received Date: 4 April 2016 Revised Date:

8 August 2017

Accepted Date: 9 October 2017

Please cite this article as: McIntyre A, Mirkowski M, Thompson S, Burhan A, Miller T, Teasell R, A Systematic Review and Meta-Analysis on the Use of Repetitive Transcranial Magnetic Stimulation for Spasticity Post Stroke, PM&R (2017), doi: 10.1016/j.pmrj.2017.10.001. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

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A Systematic Review and Meta-Analysis on the Use of Repetitive Transcranial Magnetic Stimulation for Spasticity Post Stroke

McIntyre A, 1Mirkowski M, 1Thompson S, 2,3Burhan AM, 1-,3Miller T, 1-3Teasell R

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Lawson Health Research Institute, Parkwood Institute, London, ON

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St. Joseph’s Health Care, Parkwood Institute, London, ON

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Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON

Corresponding author/reprints: Amanda McIntyre RN MSc BSc BScN Aging, Rehabilitation, and Geriatric Care, Rm. B3-123C Parkwood Institute 550 Wellington Road

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London, ON, N6C 0A7

Fax: 519-685-4036 Tel.: 519-685-4292 x41296

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[email protected]

Cover Title: rTMS for Spasticity Post Stroke # Figures: 3

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# Tables: 3 # Words: 3,971

Key Words: Stroke, rTMS, Repetitive Transcranial Magnetic Stimulation, Spasticity, Muscle Tone Conflict of Interest: Dr. Tom Miller and Dr. Robert Teasell have received funding from Allergan Canada Inc. to establish a Centre for Excellence in Spasticity at St. Joseph’s Health Care in London, Ontario.

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A Systematic Review and Meta-Analysis on the Use of Repetitive Transcranial Magnetic

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Stimulation for Upper Extremity Spasticity Post Stroke

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Cover Title: rTMS for Spasticity Post Stroke

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# Tables: 3

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# Words: 3,392

# Figures: 5

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Key Words: Stroke, rTMS, Repetitive Transcranial Magnetic Stimulation, Spasticity, Muscle Tone

Sources of Funding: None Declared.

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ABSTRACT

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Background: Spasticity is a common and potentially debilitating complication that develops after

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stroke, arising in approximately 30% of patients.

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Objective: To evaluate the effectiveness of repetitive transcranial magnetic stimulation (rTMS) in

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improving spasticity after stroke.

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Design: Meta-analysis and systematic review.

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Setting: N/A

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Patients: A total of 273 post-stroke (hemorrhagic=123, ischemic=150) participants were included

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with sample sizes ranging from 5 to 80. The majority of participants were male (66.0%) with a

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mean age ranging 55.0-64.6 years. Mean stroke duration ranged 6 months – 10 years.

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Methods: A literature search of multiple databases was conducted for articles published in English

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from January 1980 to April 2015 using select keywords. Studies were included if: 1) the population

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included was >50% stroke patients; 2) the sample size included ≥4 subjects; 3) the intervention

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applied was rTMS; and 4) upper extremity spasticity was assessed pre and post intervention.

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Randomized controlled trials (RCTs) were assessed for methodological quality using the

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Physiotherapy Evidence Database (PEDro) tool. All research designs were given a level of evidence

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according to a modified Sackett Scale.

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Main Outcome Measurements: Modified Ashworth Scale (MAS).

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Results: Ten studies met the inclusion criteria: two RCTs (PEDro scores 8-9) and eight pre-post

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studies. Meta-analyses of primarily uncontrolled pre-post studies found significant improvements in

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MAS for elbow (p<.001), wrist (p<.001), and finger flexors (p<.001). However, a meta-analysis of

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the two available RCTs failed to find a significant rTMS treatment effect on MAS for the wrist

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(standardized difference=.34, p=.30).

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Conclusions: There is limited available evidence to support the use of rTMS in improving spasticity

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post stroke. Despite the positive findings reported, better powered and appropriately controlled

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trials are necessary.

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INTRODUCTION

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Stroke is considered to be the leading cause of adult disability, often causing motor

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impairment and contributing to long-term neurological disability.1 Spasticity and increased tone2 is

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a common and potentially debilitating complication that develops after stroke, arising in

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approximately 30% of patients, with a highly variable timing of onset.3 Spasticity is defined as a

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motor disorder characterized by a velocity dependent increase in tone, and is part of the upper

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motor neuron (UMN) syndrome. Spasticity management helps improve the quality of life of many

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stroke survivors.4 Current modalities to decrease tone in the UMN syndrome have been shown to

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improve function. Current modalities such as medications or botulinum toxin injections are able to

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decrease tone generally or locally; however, treating spasticity does not necessarily improve

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weakness or motor control. As recovery of motor function after stroke is usually incomplete, recent

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research has focused on novel neurorehabilitation techniques to enhance the beneficial effects of

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treatment aimed at motor recovery.5,6 Among these are various methods of cortical stimulation,

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which include interventional paired associative stimulation, transcranial direct current stimulation

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(tDCS), implanted epidural motor cortex stimulation, and repetitive transcranial magnetic

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stimulation (rTMS).7

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rTMS is a noninvasive therapeutic intervention involving the generation of a strong

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magnetic field by a powerful electrical coil that passes unimpeded through the skull to the cerebral

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cortex producing an electric current that painlessly stimulates the targeted brain area.8 A train of

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pulses is delivered to a particular cortical region at a given intensity, as well as frequency,

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modulating brain function by influencing cortical excitability1 and allowing for the improvement of

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motor performance through facilitation of adaptive brain plasticity.5 The effect of this stimulation

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on underlying neural tissue depends particularly on the frequency at which it is administered. Lower

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frequencies, generally those below 1 Hz, suppress motor cortex excitability and thus have an

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inhibitory effect on the stimulated cortex; conversely, higher frequencies lead to facilitation by

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increasing excitability.9 The results of rTMS may include changes in cortical or subcortical

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structures that are functionally connected to the site of direct stimulation, such that its effects are

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not limited to one region.7

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The rationale for using rTMS is based upon the plastic effects that it can have on disrupted physiological mechanisms. These disruptions include impaired intracortical inhibition and

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abnormally increased transcallosal inhibition from the healthy to the lesioned hemisphere.5 In an

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effort to limit the extent of the loss of function caused by a stroke, the non- or less-affected

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hemisphere may initially have a beneficial effect on the activity of the affected hemisphere;

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however, this can subsequently become detrimental and interfere with the recovery process.10

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Interventional approaches with rTMS are targeted at normalizing the interhemispheric imbalance

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between the affected and unaffected hemispheres. The therapeutic strategy involves delivering

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excitatory rTMS on the motor cortex of the lesioned hemisphere to upregulate cortical excitability

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in this area, thus increasing intracortical facilitation. Additionally, inhibitory stimulation may be

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applied to the contralesional hemisphere, thereby down-regulating the excitability it has over the

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ipsilesional motor cortex.5 The modulation of cortical excitability through rTMS may facilitate

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neuroplastic changes that potentially reestablish disrupted transcallosal inhibitory pathways

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between the primary motor areas of both hemispheres, thus leading to a restoration of

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interhemispheric balance and improved motor function.1 Therefore, rTMS serves as a promising

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complementary treatment used alongside traditional therapies to enhance motor neurorehabilitation

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in stroke patients. Given that this therapy is relatively novel, few studies have evaluated its

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effectiveness in improving spasticity. It was our objective to perform a systematic review and meta-

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analysis to evaluate the effectiveness of rTMS in improving upper extremity spasticity after stroke.

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METHODS

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Literature Search

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A literature search of multiple databases (i.e., Pubmed, CINAHL, Scopus, Cochrane, and

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EMBASE) was conducted for articles published between January 1980 and April 2015 in English.

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Selected keywords included: repetitive transcranial magnetic stimulation, rTMS, stroke,

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cerebrovascular accident, spasticity, upper limb, limb disorders, upper motor neuron syndrome,

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and movement disorders. Variations of keywords were individualized for each scientific database.

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The references of all retrieved articles were reviewed to ensure all relevant articles were included

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for data synthesis.

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Study Selection

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Studies were included if they satisfied the following four a priori inclusion criteria:

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the population included was >50% stroke patients;

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the sample size included four or more subjects;

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the intervention applied was rTMS; and

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upper extremity spasticity was assessed pre and post intervention

To determine if the study specifically applied rTMS, a physician (AB) trained in the

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administration of this therapy reviewed each article individually to verify that the methods were

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consistent with typical application. There were no specified criteria in terms of the intensity or

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duration of therapy. Studies assessing concomitant therapies (e.g., botulinum toxin,

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pharmacological drugs) were included for review. Only studies providing consistent rTMS

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protocols were included in the meta-analysis; studies providing concomitant therapy (i.e., botulinum

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toxin type A) were excluded from meta-analysis but still included for descriptive review. Studies

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were excluded if information on patient demographics, research design, intervention and/or results

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could not accurately be extracted from the article. Additionally, studies that assessed the effect of

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rTMS priming were excluded.

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Study Appraisal

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Two independent reviewers (AMc; ST) assessed randomized controlled trials (RCTs) for

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methodological quality using the Physiotherapy Evidence Database (PEDro) scoring system .11 The

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tool assesses 11 items on study quality that are answered using a ‘yes’ (score=1) or ‘no’ (score=0).

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The first item is a measure of external validity and is not used in calculating the final score; thus,

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the maximum score that can be achieved is 10. All research designs were given a level of evidence

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according to a modified Sackett Scale (Table 1).12 Insert Table 1 about here.

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Data Synthesis

Data extracted from the studies included author(s), year, country of origin, subject and

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treatment characteristics (e.g., age, gender, stroke onset), study design, intervention/control

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protocol, outcome measure pre-treatment and post-treatment scores, and adverse effects. The mean

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and standard deviation (median and interquartile range, as necessary) at baseline and follow-up was

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extracted for all available spasticity outcome measures. To approximate an effect size, medians

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were considered to be equal to means when the interquartile range was deemed to represent a

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normal distribution; to obtain associated standard deviations, interquartile ranges were divided by

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1.35. Four meta-analyses were completed using Comprehensive Meta-Analysis software (version 2,

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Biostat Inc., Englewood, NJ, 2005). Pooled analyses were conducted using a fixed or random

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effects model when there was little or great heterogeneity, respectively.

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Ashworth scale (MAS) was assessed. Using the baseline (pre-treatment) and follow-up (post-

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treatment) means with standard deviations, a pooled mean difference (plus standard error and 95%

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confidence interval, CI) between baseline and post-intervention was calculated. If a pre- or post-

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test mean did not have an accompanying standard deviation, a p value or Cohen’s d value was used

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instead.

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Outcome Measure

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The MAS was designed to assess muscle tone and evaluate an individual’s level of spasticity. The MAS uses a six-point classification scale ranging from 0 to 4 where 0 indicates no

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increase in muscle tone, 1 indicates a slight increase in muscle tone, manifested by a catch and

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release or by minimal resistance at the end of the range of motion when the affected part(s) is/are

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moved in flexion or extension, 1+ indicates a slight increase in muscle tone, manifested by a catch,

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followed by minimal resistance throughout the remainder (less than half) of the ROM, 2 indicates

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more marked increase in muscle tone through most of the ROM, but affected part(s) easily moved,

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3 indicates considerable increase in muscle tone, passive movement difficult, and 4 indicates that

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the affected part(s) is(are) rigid in flexion or extension.13 The MAS has been validated as an

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assessment tool for the evaluation of spasticity post stroke.14 Results from other outcome measures

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were reported in the included studies, such as those that evaluated motor functioning. However,

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since the objective of this study was to evaluate change in spasticity, these measures were not

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considered when interpreting findings.

RESULTS

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Study Selection and Quality

For this systematic review and meta-analysis, the literature search yielded 350 studies; the selection process is presented in Figure 1. In total, ten studies published from 2008 to 2015 met

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inclusion criteria (Figure 1) including one RCT,4 one cross-over RCT,15 and eight pre-post

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studies.16,17-23 The methodological quality for both RCTs was excellent, with scores ranging 8-9 on

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the PEDro scale, and providing level 1a evidence. The eight pre-post studies were rated as level 4

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evidence (Table 2).

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Insert Figure 1 and Table 2 about here.

Patient Characteristics Table 2 presents patient characteristics for each of the studies involved. A total of 273 poststroke (hemorrhagic=123, ischemic=150) participants were included in all ten studies; however,

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sample sizes ranged considerably from 5 to 80 participants. The majority of participants were male

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(66.0%) with a mean age ranging 55.0-64.6 years; Yamada et al.16 did not report on participants’

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gender. While Mally and Dinya17 and Yamada et al.22 did not report which side their participants’

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hemisphere was affected, among the other studies, hemispheres were affected on the left and right

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sides in 58 and 60 participants, respectively. The mean stroke duration ranged 6 months - 10.0

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years.

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Study Design

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A description of the study design and methodology for each article is reported in Table 3. The RCTs by Barros-Galvao et al.4 and Etoh et al.15 compared an intervention group (receiving

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rTMS) to a sham control group. In both studies, individuals receiving active treatment received 1

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Hz to the unaffected hemisphere for ten sessions; however, Barros-Galvao et al.4 delivered rTMS at

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1,500 pulses whereas Etoh et al.15 delivered rTMS at 240 pulses. Both studies provided their active

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and control participants with physiotherapy and/or occupational therapy (0.5-2 hours).

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The eight pre-post studies followed similar treatment regimens whereby rTMS was

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delivered to all enrolled participants. Four of these studies were led by the author Kakuda18-20,23 with

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almost identical treatment protocols. In all four studies, 22 sessions of motor rTMS (1,200 pulses, 1

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Hz) as well as 1 hour of occupational therapy and 1 hour of self-training were applied to the

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unaffected hemisphere. Two of their studies provided concomitant therapy to participants. Kakuda

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et al.19 administered 100 mg daily Levadopa to participants for four weeks pre rTMS until four

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weeks post rTMS. Kakuda et al.18 injected botulinum toxin type A (maximum 240 U) into muscles

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of the affected limb four weeks before rTMS. Two pre-post studies were led by Yamada.16,22

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Yamada et al.22 applied contralesional rTMS (1 Hz, 2,400 pulses), occupational therapy, self-

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training, and botulinum toxin type A to individuals over 15 days. The study by Yamada et al.16 was

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the only one to apply rTMS to both the contralesional (1 Hz) and ipsilesional (10 Hz) hemispheres

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in all patients, in addition to occupational therapy and self-training over 15 days. The remaining

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pre-post study by Mally and Dinya17 applied motor rTMS (100 pulses; 1 Hz) to the unaffected

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and/or affected hemisphere for 14 sessions; stimulation sites were determined by testing the effect

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of one pulse rTMS to the affected/unaffected hemisphere and visualizing for movement in the

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paretic side prior to treatment.

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The site of rTMS application was the location in which the largest motor-evoked potential

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could be elicited in the first dorsal interosseous muscle of the unaffected upper limb. In all studies,

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with the exception of that by Mally and Dinya,17 the intensity of stimulation was set at 90% of

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motor threshold.

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Insert Table 3 about here.

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Eight studies reported that there were no adverse effects as a result of the rTMS

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intervention.4,15,16,18,20-23 The remaining two studies did not report any information on whether

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participants experienced adverse effects post intervention.17,19

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Effectiveness

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Elbow

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The results from each study are reported in Table 3. With the exception of Mally and

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Dinya17 who assessed upper and lower extremity spasticity, the remaining studies examined only

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spasticity in the elbow, wrist, and fingers. Four studies15,16,18,20 assessed change in elbow spasticity

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using the MAS; three of the studies16,18,20 reported significant improvement post intervention and

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this improvement was maintained at 4-week follow-up.18 However, the cross-over RCT by Etoh et

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al.15 found no significant improvement in elbow spasticity post intervention or at 4-week follow-up.

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For the meta-analysis, a fixed effects model was used due to little heterogeneity between the two

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studies included (Q = 1.75; I2 = 42.9; df = 1). The standard difference in means was significant from

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baseline to post intervention demonstrating a treatment effect on wrist MAS scores (p=.032; Figure

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2).

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Insert Figure 2 about here.

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Wrist Nine studies4,15,16,18-23 assessed change in wrist spasticity using the MAS. Etoh et al.15 and

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Kakuda et al.19 reported no improvement in wrist spasticity post intervention or at 4-week follow-

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up. However, the remaining seven studies reported significant improvement post intervention.4,16,18-

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al.22 reported that while both of their treatment groups improved, there were no significant between-

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group differences in improvement (rTMS only vs. rTMS + botulinum toxin type A). Six studies4,20-

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meta-analysis, a fixed effects model was used due to little heterogeneity between the studies

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included (Q =11.206; I2 = 55.4; df = 5). The standard difference in means was significant from

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baseline to post intervention demonstrating a treatment effect on wrist MAS scores (p<.001; Figure

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3). To examine the contribution of only the two RCTs, a separate meta-analysis was conducted

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comparing the treatment to sham; a fixed effects model (Q = 1.021; I2 = 2.1; df = 1) demonstrated

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that the standard difference in means was not significant from baseline to post intervention (p=.300;

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Figure 4).

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This effect was maintained at four-week follow-up in two studies.18,19 Interestingly, Yamada et

Eight studies15,16,18-23 examined change in finger spasticity using the MAS. Six studies

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Fingers

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Insert Figure 3 and 4 about here.

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were included in the meta-analysis of rTMS on wrist spasticity as measured by the MAS. For the

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reported improvement post intervention16,18-22 and three studies at 4-week follow-up.15,18,19 Five

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studies20-23 were included in the meta-analysis of rTMS on finger spasticity as measured by the

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MAS. A fixed effects model was used due to little heterogeneity between the studies included for

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this analysis (Q = 3.392; I2 = 0; df = 4). The standard difference in means was significant from

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baseline to post intervention demonstrating a treatment effect on finger MAS scores (p<.001;

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Figure 5).

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Mally and Dinya17 measured change in upper extremity spasticity (predominately fingers) using an outcome measure created by the authors (i.e., “Score of Spasticity”) whereby the rating

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system was similar to that of the MAS but rated on a scale of 0-3 instead of 0-4. The authors

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reported significant improvement in upper extremity spasticity post intervention, and at 1- and 3-

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month follow-up for all groups (except for group D at 3 month follow-up; see Table 3). Insert Figure 5 about here.

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DISCUSSION

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This systematic review and meta-analysis aimed to evaluate the effectiveness of rTMS in

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improving spasticity post stroke. In an assessment of its effect on elbow flexors, three level 4 pre-

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post studies demonstrated improvement post intervention but this was different than the one level 1a

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cross-over RCT reporting no improvement; however, the meta-analysis demonstrated a significant

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treatment effect immediately post intervention (p<.001). Similarly, while one level 4 study reported

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improvement at 4-week follow-up, the level 1a cross-over RCT found no improvement. Regarding

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wrist flexors, the results from the first meta-analysis (four level 4 studies and one level 1a RCT)

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found a significant improvement post intervention; however, the meta-analysis of only the two

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RCTs did not show significant improvement. Non-meta-analytic data (two level 4 studies)

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supported significant improvement at 4-week follow-up as well. For finger flexors, the second

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meta-analysis (four level 4 studies) found a significant improvement in spasticity post intervention;

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this improvement was shown to be maintained at 4-week follow-up by two level 4 studies and one

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level 1a cross-over RCT.

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Spasticity is a complex disorder, encompassing a considerably diverse variety of symptoms,

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which can have a negative impact on the quality of life of stroke survivors.24 Available therapies to

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date include physiotherapy modalities as well as pharmacologic agents such as botulinum toxin.

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While the latter has demonstrated effectiveness in a post-stroke population,25 additional, non-

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pharmacological novel approaches are necessary since no one treatment appears to be completely

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effective for all patients. The use of rTMS as a therapeutic tool in stroke recovery is relatively new,

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and has been reported to be of benefit in the rehabilitation of post-stroke aphasia and

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hemineglect.10,26 Within the confines of the included studies’ limitations, this systematic review and

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meta-analysis revealed that rTMS may be beneficial in improving spasticity post stroke.

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The limitations of included studies are similar to those reported by other systematic reviews and meta-analyses published on rTMS. From a methodological standpoint, the primary limitation

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among eight studies was the use of a pre-post research design. Since the majority of studies were

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uncontrolled, the authors’ conclusions are subject to some bias and open to interpretation. In the

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current review, two studies18,22 employed rTMS concomitantly with either botulinum toxin type A18

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or Levadopa19 without a control group. This is especially significant as botulinum toxin type A has

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been shown to significantly and independently improve spasticity as measured using the MAS.25

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Therefore, the positive findings reported by Kakuda et al.18 and Yamada et al.22 may have resulted

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from the botulinum toxin type A, the rTMS or both. A complex, rigorous research design such as a

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multiple-armed RCT can overcome this problem by separating out the individual as well as additive

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effects of combination therapies. Regardless, it is important to note that significant treatment effects

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were demonstrated by the meta-analyses which excluded groups receiving concomitant therapies.

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From a rehabilitation perspective, increased intensity and frequency of rehabilitation

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sessions has been shown to positively benefit motor outcomes.27 The underlying assumption is that

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to induce long-term effects, highly intense sessions that are frequent and of long duration are

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necessary. From a neuromodulation perspective, this viewpoint holds true as well. To induce

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neuroplastic effects, high pulse counts and a long duration are required. On average, the total

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number of minutes of rTMS applied to participants in these studies ranged 400-480 minutes over

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two weeks and the pulse count ranged 100-2,400 per session. Since rehabilitation is a long-term

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process often lasting months to years, these diverse rTMS protocols may be suboptimal in their

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current form. Future trials should consider evaluating the dose-response relationship between rTMS

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and improvement in spasticity. Considering the mechanism by which rTMS is hypothesized to be effective, all but one

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study included for review utilized rTMS at 1 Hz to inhibit the contralesional hemisphere. An rTMS

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frequency of 1 Hz on the contralesional side is likely to help restore interhemispheric

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excitation/inhibition balance thereby facilitating motor recovery.26 The re-balance of inter-

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hemispheric cortical excitability and its impact on spasticity is unknown. Excitability-increasing

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high frequency rTMS of ipsilesional M1 or excitability-decreasing low frequency rTMS of

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contralesional M1 is thought to improve motor abilities in stroke patients.26,28 The positive clinical

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signs of spasticity include enhanced stretch reflex, increased tone, and exaggerated tendon reflexes,

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whereas the negative signs include loss of dexterity and slowness of movement and control of

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muscles and limb segments. The negative symptoms in the UMN syndrome (i.e., weakness) are due

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to disruption of the pathways between the supraspinal and the motor subsystems. The influence of

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rTMS may improve the hemispheric balance of excitation and inhibition, thereby reducing tone, as

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measured by the Ashworth scale.

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Conceptually, a potentially more efficacious protocol for future studies may involve

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providing bi-hemispheric stimulation to patients whereby the contralesional hemisphere is inhibited

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via 1 Hz and the ipsilesional hemisphere is activated via HF TMS 10 Hz. This type of protocol was

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tested in just one study16 on post-stroke spasticity. Future studies should consider designing RCTs

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which compare uni- versus bi-hemispheric stimulation. Typical rTMS has been reported to be weak

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and have only short-term effects lasting 30 minutes. Another evolving neuroplastic paradigm

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involves theta-burst stimulation (TBS) which is a method for rapid, controllable, consistent, and

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long-lasting stimulation.29 A pilot study by Huang and Rothwell30 demonstrated 50 Hz TBS to be

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safe and effective in targeting neurons in the motor cortex. Additional studies should be conducted

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which examine TBS for spasticity post stroke.

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The current study is not without its own limitations. It is confined by its inclusion criteria which excluded non-English trials. Therefore, studies published in alternate languages were not

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included in the analysis.

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CONCLUSION

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There is limited available evidence to date to support the use of rTMS in improving

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spasticity post stroke. Despite the positive findings reported by several studies, they are not without

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their own significant methodological limitations. The effectiveness of rTMS for use in stroke

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rehabilitation should be verified further; thus, additional better powered, high-quality RCTs are

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needed. Furthermore, its use in combination with other tone-reducing modalities, such as botulinum

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toxin, requires exploration.

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REFERENCES

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3.

Thibaut A, Chatelle C, Ziegler E, Bruno MA, Laureys S, Gosseries O. Spasticity after stroke: physiology, assessment and treatment. Brain Inj 2013;27(10):1093-105.

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322 323

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therapy to reduce upper-limb spasticity in patients with stroke: a randomized controlled

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Hao Z, Wang D, Zeng Y, Liu M. Repetitive transcranial magnetic stimulation for

improving function after stroke. Cochrane 2013;5:CD008862.

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Kobayashi M, Pascual-Leone A. Transcranial magnetic stimulation in neurology. Lancet

Neurol 2003;2(3):145-56.

340 341

Talelli P, Rothwell J. Does brain stimulation after stroke have a future? Curr Opin Neurol 2006;19(6):543-50.

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Lefaucheur JP. Stroke recovery can be enhanced by using repetitive transcranial magnetic

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Hummel FC, Cohen LG. Non-invasive brain stimulation: a new strategy to improve

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Hoyer EH, Celnik PA. Understanding and enhancing motor recovery after stroke using

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Moseley AM, Herbert RD, Sherrington C, Maher CG. Evidence for physiotherapy practice: a survey of the Physiotherapy Evidence Database (PEDro). Aus J Physio 2002;48(1):43-9.

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teach EBM. Toronto, Ontario: Elsevier Churchill Livingstone; 2005.

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Bohannon RW, Smith MB. Interrater reliability of a modified Ashworth scale of muscle spasticity. Phys Ther 1987;67(2):206-7.

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Straus SE RW, Glasziou P, Haynes RB. Evidencebased medicine: How to practice and

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Blackburn M, van Vliet P, Mockett SP. Reliability of measurements obtained with the modified Ashworth scale in the lower extremities of people with stroke. Phys Ther

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2002;82(1):25-34.

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Etoh S, Noma T, Ikeda K, et al. Effects of repetitive trascranial magnetic stimulation on repetitive facilitation exercises of the hemiplegic hand in chronic stroke patients. J Rehab

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Med 2013;45(9):843-7.

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Yamada N, Kakuda W, Kondo T, Shimizu M, Mitani S, Abo M. Bihemispheric repetitive

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transcranial magnetic stimulation (rTMS). Brain Res Bull 2008;76(4):388-95.

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Mally J, Dinya E. Recovery of motor disability and spasticity in post-stroke after repetitive

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Kakuda W, Abo M, Momosaki R, et al. Combined therapeutic application of botulinum toxin type A, low-frequency rTMS, and intensive occupational therapy for post-stroke

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spastic upper limb hemiparesis. Eur J Phys Rehab Med 2012;48(1):47-55. 19.

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approach for upper limb hemiparesis after stroke. Int J Neurosci 2011b;121(7):373-8.

365 366

Kakuda W, Abo M, Kobayashi K, et al. Combination treatment of low-frequency rTMS and

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Kakuda W, Abo M, Kobayashi K, et al. Low-frequency repetitive transcranial magnetic

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stimulation and intensive occupational therapy for poststroke patients with upper limb

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parameters. Int J Neurosci 2015;125(1):25-31.

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transcranial magnetic stimulation and intensive occupational therapy in post-stroke patients

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Kakuda W, Abo M, Kobayashi K, et al. Anti-spastic effect of low-frequency rTMS applied

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Ward AB. A literature review of the pathophysiology and onset of post-stroke spasticity.

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380

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abobotulinumtoxinA in clinical trials for adult upper limb spasticity. Amer J Phys Med

384

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Lefaucheur JP, André-Obadia N, Antal A, et al. Evidence-based guidelines on the

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therapeutic use of repetitive transcranial magnetic stimulation (rTMS). Clin

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training intensity on locomotor performance in individuals with chronic stroke. J Neurol

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386

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Rossini PM, Burke D, Chen R, et al. Non-invasive electrical and magnetic stimulation of the brain, spinal cord, roots and peripheral nerves: Basic principles and procedures for

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399

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SC

398

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400

Table 1: Modified Sackett Scale

401 Description

1a

More than one randomized controlled trial (PEDro score ≥6)

1b

One randomized controlled trial (PEDro score ≥6)

2

Randomized controlled trial (PEDro score <6), prospective controlled trials, cohort studies

3

Case-control

4

Case series, pre-post or post-test

5

Observational, case report or clinical consensus

Conflicting

In the absence of evidence, agreement by a group of experts on the appropriate treatment

M AN U

SC

RI PT

Level

course

AC C

EP

TE D

402

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21

Research Country

Year Kondo et al.

Evidence

Age

N

Males Females Design

(PEDro)

Japan

10

Pre-Post

Level 4

8

Brazil

20

RCT

Level 1a (9)

13

2

Barros Galvao et al. 2014 Yamada et al.

Japan

80

Pre-Post

Level 4

50

Yamada et al.

Japan

8

Pre-Post

Level 4

Japan

18

RCT cross-

Level 1a (8)

2013 Kakuda et al.

over Japan

14

Pre-Post

Japan

39

Pre-Post

2012 Kakuda et al. 2011a

Left

mean ± SD (mo)

Hem

57.4 ± 8.1

86.0 ± 52.8

7

3

3

7

E: 57.4 ± 12.0

E: 47.8 ± 43.2

3

17

10

10

C: 64.6 ± 6.8

C: 58.9 ± 27.2

E: 62.9 ± 10.2

E: 62.0 ± 51.7

41

39

N/R

N/R

C: 57.2 ± 15.2

C: 48.0 ± 29.8

Isch

Right

N/R

62.8 ± 4.9

84.3 ± 87.2

4

4

5

3

14

4

59.7 ± 11.0

29.9 ± 18.8

5

13

8

10

Level 4

10

4

54.9 ± 9.2

87.1 ± 48.2

9

5

5

6

Level 4

30

9

56.5 ± 16.0

50.3 ± 37.8

23

16

23

16

AC C

Etoh et al.

Affected Side

N/R

EP

2013

30

TE D

2014

7

Stroke Type

mean ± SD (yr)

M AN U

2015

Stroke Onset

SC

Author,

RI PT

Table 2. Study Subject Characteristics

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22

Kakuda et al.

Japan

5

Pre-Post

Level 4

3

2

61.0 ± 4.5

Japan

15

Pre-Post

Level 4

10

5

55.0 ± 17.0

Hungary

64

Pre-Post

Level 4

37

27

57.6 ± 10.8

64.0 ± 57.0

4

1

3

2

57.0 ± 55.0

9

6

9

6

120.0 ± 76.8

18

46

N/R

N/R

Kakuda et al.

Mally &

SC

2010

RI PT

2011b

Dinya 2008

M AN U

Note: C=control group; E=experimental group; Hem=hemorrhagic; Isch=ischemic; Mo=month; N=number; N/R=not reported; NS=non-stroke;

AC C

EP

TE D

PEDro=physiotherapy evidence database; S=stroke; SD=standard deviation; Yr=year

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Table 3. Study protocol, outcome measures and results for all included studies Motor rTMS Intervention Protocol Control

Pulses; No. Frequency

Intensity Sessions

Kondo et

Contralesional

1 Hz

al. 2015

Contralesional

1 Hz

Galvao et

Rehab/Session

90%

2,400; 12, 40 min

120 min OT +

RMT

sessions over 15

120 min self

days Barros

Outcome

90%

1,500; 10 sessions

RMT

at 3/wk

None

30 min PT

Sham

1 Hz

90%

2,400; 12 , 40 min

RMT

MAS

Elbow

Post rTMS

MAS

Wrist Fingers +

Elbow

+

Post sham

--

Post BGD

+

4-week rTMS

+

4-week sham

--

4-week BGD

--

rTMS

sessions over 15

120 min self +

without

days

botulinum toxin

botulinum

type A

toxin type

Post rTMS only

A

Post BGD

MAS Post rTMS/ botulinum toxin type A

Elbow

+

Wrist Fingers

Post rTMS

120 min OT +

AC C

al. 2014

Contralesional

EP

TE D

al. 2014

Yamada et

Results

Protocol

SC

Target

M AN U

Year

Additional

RI PT

Author,

Wrist Fingers ++

++

++

++

--

+

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24

Bihemispheric

al. 2013

1 Hz contra

90%

2,000 each; 10, 40

120 min OT +

10 Hz ips

RMT

min sessions over

120 min self

2013

Kakuda et

Contralesional

1 Hz

al. 2012

90%

240; 10, 40 min

60-120 min

RMT

sessions over 14

voluntary

days

PT/OT

90%

1,200; 22, 20 min

RMT

sessions over 15 days

Sham

SC

1 Hz

M AN U

Contralesional

60 min OT +

None

60 min self +

botulinum toxin

Contralesional

1 Hz

al. 2011a

TE D

type A

Kakuda et

90%

1,200; 22, 20 min

60 min OT +

RMT

sessions over 15

60 min self +

None

1 Hz

90%

1,200; 22, 20 min

AC C

al. 2011b

Contralesional

EP

days

Kakuda et

RMT

60 min OT +

MAS Post rTMS

15 days Etoh et al.

None

RI PT

Yamada et

None

Elbow

Wrist Fingers

+

+

+

Elbow Wrist

Fingers

Post rTMS

--

--

--

Post sham

--

--

--

4-week BGD

--

--

+

Elbow

Wrist

Fingers

++

++

++

+

+

+

Elbow

Wrist Fingers

MAS

MAS Post rTMS/ botulinum toxin type A 4-week FU MAS Post rTMS

++

++

4-week FU

+

+

MAS

Elbow

Wrist Fingers

sessions over 15

60 min self +

Post rTMS/Levadopa

--

--

days

Levadopa

4-week FU

--

--

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Contralesional

1 Hz

al. 2010

90%

1,200; 22, 20 min

60 min OT +

RMT

sessions over 15

60 min self

days Mally &

Bihemispheric

30%

100; 2 sessions per

2.3T

day for 1 wk

None

MAS Post rTMS

None

M AN U

SC

Dinya 2008

1 Hz

None

RI PT

Kakuda et

a

Spasticity

Elbow

Wrist

Fingers

++

+

+

b

A

B

C

D

Post rTMS

++ ++ ++ +

1 month

++ ++ ++ +

3 month

++ ++ ++ - -

Note. + = statistically significant improvement at p<.05; ++ = statistically significant improvement at p<.01; - - = No significant difference at p>.05 a

Score of Spasticity – outcome created by the authors whereby 0=none, 1=slight, 2=fingers in flexion and passive extension to elbow difficult, 3=expressive flexion

b

A, B, C, D, refer to groups A) movement produced when stimulation was applied to both sides simultaneously, B) stimulation of either side produced no movements, C)

TE D

stimulation of contralateral hemisphere induced movement, and D) stimulation of ipsilateral hemisphere induced movement.

AC C

EP

BGD = Between-Group Difference; Contra = FU = Follow-up; OT = occupational therapy; PT = physical therapy; RMT = resting motor threshold

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Figure Captions

RI PT

Figure 1. Study Selection Process Figure 2. Meta-analysis of two uncontrolled studies assessing within-group improvements in MAS of the elbow flexors from baseline to post intervention

SC

Figure 3. Meta-analysis of five uncontrolled studies assessing within-group improvements in MAS of the wrist flexors from baseline to post

M AN U

intervention

Figure 4. Meta-analysis of two RCTs assessing between-group improvements in MAS of the wrist flexors from baseline to post intervention Figure 5. Meta-analysis of four uncontrolled studies assessing within-group improvements in MAS of the finger flexors from baseline to

AC C

EP

TE D

post intervention

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Records identified through database searching (n = 350)

Additional records identified through other sources (n = 0)

SC

Identification

PRISMA 2009 Flow Diagram

M AN U

Records screened (n = 341)

Records excluded (n = 328)

Full-text articles assessed for eligibility (n = 13)

Full-text articles excluded, based on not satisfying inclusion criteria (n = 3)

TE D EP AC C

Included

Eligibility

Screening

Records after duplicates removed (n = 341)

Studies included in qualitative synthesis (n = 10)

Studies included in quantitative synthesis (meta-analysis) (n = 10)

From: Moher D, Liberati A, Tetzlaff J, Altman DG, The PRISMA Group (2009). Preferred Reporting Items for Systematic Reviews and MetaAnalyses: The PRISMA Statement. PLoS Med 6(6): e1000097. doi:10.1371/journal.pmed1000097

For more information, visit www.prisma-statement.org.

Study name

Statistics for each study Std diff in means

Standard error

Variance

Lower limit

Upper limit

RI PT

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Std diff in means and 95% CI

Z-Value

p-Value

0.000

0.471

0.222

-0.924

0.924

0.000

1.000

0.733

0.291

0.085

0.163

1.303

2.520

0.012

0.531

0.247

0.061

0.046

1.016

2.145

SC

Etoh et. al 2013 Kakuda et al. 2010

0.032

AC C

EP

TE D

M AN U

-1.00

-0.50

0.00

0.50

1.00

Statistics for each study Std diff Standard in means error

Variance

Lower limit

Upper limit

Std diff in means and 95% CI

Z-Value p-Value

SC

Study name

0.693

0.352

0.124

0.003

1.384

1.969

0.049

Barros Galvao et al. 2014

1.441

0.451

0.204

0.556

2.326

3.192

0.001

M AN U

Kondo et al. 2015

Yamada et al. 2014

0.849

0.189

0.036

0.478

1.220

4.487

0.000

Kakuda et al. 2011a

0.329

0.164

0.027

0.007

0.651

2.002

0.045

Kakuda et al. 2010

0.667

0.285

0.081

0.107

1.226

2.336

0.020

0.333

0.111

-0.653

0.653

0.000

1.000

0.165

0.027

0.286

0.932

3.701

0.000

EP

TE D

0.000 0.609

AC C

Etoh et al. 2013

RI PT

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-3.00

-1.50

0.00

1.50

3.00

Statistics for each study Std diff Standard in means error

Variance

Lower limit

Upper limit

Std diff in means and 95% CI

Z-Value p-Value

0.665

0.459

0.211

-0.235

1.566

1.448

Etoh et al. 2013

0.000

0.471

0.222

-0.924

0.924

0.000

0.341

0.329

0.108

-0.304

0.986

1.037

TE D EP

0.148

1.000

M AN U

Barros Galvao et al. 2014

AC C

SC

Study name

RI PT

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0.300

-1.00

-0.50

0.00

0.50

1.00

Statistics for each study Std diff Standard in means error

Variance

Lower limit

Upper limit

Std diff in means and 95% CI

Z-Value p-Value

SC

Study name

Kondo et al. 2015

0.768

0.360

0.130

0.063

1.474

2.135

Yamada et al. 2014

0.749

0.184

0.034

0.389

1.109

4.080

Kakuda et al. 2011a

0.336

0.165

0.027

0.013

0.658

2.041

0.041

Kakuda et al. 2010

0.465

0.272

0.074 -0.068

0.997

1.710

0.087

Etoh et al. 2013

0.675

0.485

0.235 -0.275

1.625

1.393

0.164

0.540

0.104

0.011

0.744

5.181

0.000

AC C

EP

0.033

0.000

M AN U

TE D

0.336

RI PT

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-1.00

-0.50

0.00

0.50

1.00