Agreed Definitions and a Shared Vision for New Standards in Stroke Recovery Research: The Stroke Recovery and Rehabilitation Roundtable Taskforce

Mapping causal circuit dynamics in stroke using simultaneous electroencephalography and transcranial magnetic stimulation

BACKGROUND

Motor impairment after stroke is due not only to direct tissue loss but also to disrupted connectivity within the motor network. Mixed results from studies attempting to enhance motor recovery with Transcranial Magnetic Stimulation (TMS) highlight the need for a better understanding of both connectivity after stroke and the impact of TMS on this connectivity. This study used TMS-EEG to map the causal information flow in the motor network of healthy adult subjects and define how stroke alters these circuits.

METHODS

Fourteen stroke patients and 12 controls received TMS to two sites (bilateral primary motor cortices) during two motor tasks (paretic/dominant hand movement vs. rest) while EEG measured the cortical response to TMS pulses. TMS-EEG based connectivity measurements were derived for each hemisphere and the change in connectivity (ΔC) between the two motor tasks was calculated. We analyzed if ΔC for each hemisphere differed between the stroke and control groups or across TMS sites, and whether ΔC correlated with arm function in stroke patients.

RESULTS

Right hand movement increased connectivity in the left compared to the right hemisphere in controls, while hand movement did not significantly change connectivity in either hemisphere in stroke. Stroke patients with the largest increase in healthy hemisphere connectivity during paretic hand movement had the best arm function.

CONCLUSIONS

TMS-EEG measurements are sensitive to movement-induced changes in brain connectivity. These measurements may characterize clinically meaningful changes in circuit dynamics after stroke, thus providing specific targets for trials of TMS in post-stroke rehabilitation.

Why Are Stroke Rehabilitation Trial Recruitment Rates in Single Digits?

Background: Recruitment of patients in early subacute rehabilitation trials (<30 days post-stroke) presents unique challenges compared to conventional stroke trials recruiting individuals >6 months post-stroke. Preclinical studies suggest treatments be initiated sooner after stroke, thus requiring stroke rehabilitation trials be conducted within days post-stroke. How do specific inclusion and exclusion criteria affect trial recruitment rates for early stroke rehabilitation trials?

Objectives: Provide estimates of trial recruitment based on screening and enrollment data from a phase II early stroke rehabilitation trial.

Methods: CPASS, a phase II intervention trial screened ischemic stroke patients in acute care (18-months, N = 395) and inpatient rehabilitation (22-months, N = 673). Patients were stratified by upper extremity (UE) impairment into mild (NIHSS motor arm = 0, 1); moderate (NIHSS = 2, 3); severe (NIHSS = 4) and numbers of patients disqualified due to CPASS exclusion criteria determined. We also examined if a motor-specific evaluation (Action Research Arm Test, ARAT) increases the pool of eligible patients disqualified by the NIHSS motor arm item.

Results: CPASS recruitment in acute care (5.3%) and inpatient rehabilitation (5%) was comparable to prior trials. In acute care, a short stay (7–17-days), prior stroke (13.5% in moderately; 13.2% in severely impaired) disqualified the majority. In inpatient rehabilitation, the majority (40.8%) were excluded for “too mild” impairment. The next majority were disqualified for reaching inpatient rehabilitation “too late” to participate in an early stroke trial (15% in moderately; 24% in severely impaired). Mean ARAT in the “too mild” showed significant impairment and potential to benefit from participation in select UE rehabilitation trials.

Conclusions: Screening of ischemic stroke patients while they are still in acute care is crucial to successful recruitment for early stroke rehabilitation trials. A significant proportion of eligible patients are lost to “short length of stay” in acute care, and arrive to inpatient rehabilitation “too late” for an early rehabilitation trial. Additional screening of mildly impaired patients using a motor function specific scale will benefit the trial recruitment and generalizability.

Trial Registration Number:http://www.clinicaltrials.gov Identifier: NCT02235974.

Study Paradigms and Principles Investigated in Motor Learning Research After Stroke: A Scoping Review

OBJECTIVES

To (1) characterize study paradigms used to investigate motor learning (ML) poststroke and (2) summarize the effects of different ML principles in promoting skill acquisition and retention. Our secondary objective is to evaluate the clinical utility of ML principles on stroke rehabilitation.

DATA SOURCES

Medline, Excerpta Medica Database, Allied and Complementary Medicine, Cumulative Index to Nursing and Allied Health Literature, and Cochrane Central Register of Controlled Trials were searched from inception on October 24, 2018 and repeated on June 23, 2020. Scopus was searched on January 24, 2019 and July 22, 2020 to identify additional studies.

STUDY SELECTION

Our search included keywords and concepts to represent stroke and "motor learning. An iterative process was used to generate study selection criteria. Three authors independently completed title, abstract, and full-text screening.

DATA EXTRACTION

Three reviewers independently completed data extraction.

DATA SYNTHESIS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension guidelines for scoping reviews were used to guide our synthesis. Thirty-nine studies were included. Study designs were heterogeneous, including variability in tasks practiced, acquisition parameters, and retention intervals. ML principles investigated included practice complexity, feedback, motor imagery, mental practice, action observation, implicit and explicit information, aerobic exercise, and neurostimulation. An additional 2 patient-related factors that influence ML were included: stroke characteristics and sleep. Practice complexity, feedback, and mental practice/action observation most consistently promoted ML, while provision of explicit information and more severe strokes were detrimental to ML. Other factors (ie, sleep, practice structure, aerobic exercise, neurostimulation) had a less clear influence on learning.

CONCLUSIONS

Improved consistency of reporting in ML studies is needed to improve study comparability and facilitate meta-analyses to better understand the influence of ML principles on learning poststroke. Knowledge of ML principles and patient-related factors that influence ML, with clinical judgment can guide neurologic rehabilitation delivery to improve patient motor outcomes.

Effect of post-stroke spasticity on voluntary movement of the upper limb

Background

Hemiparesis following stroke is often accompanied by spasticity. Spasticity is one factor among the multiple components of the upper motor neuron syndrome that contributes to movement impairment. However, the specific contribution of spasticity is difficult to isolate and quantify. We propose a new method of quantification and evaluation of the impact of spasticity on the quality of movement following stroke.

Methods

Spasticity was assessed using the Tonic Stretch Reflex Threshold (TSRT). TSRT was analyzed in relation to stochastic models of motion to quantify the deviation of the hemiparetic upper limb motion from the normal motion patterns during a reaching task. Specifically, we assessed the impact of spasticity in the elbow flexors on reaching motion patterns using two distinct measures of the ‘distance’ between pathological and normal movement, (a) the bidirectional Kullback–Liebler divergence (BKLD) and (b) Hellinger’s distance (HD). These measures differ in their sensitivity to different confounding variables. Motor impairment was assessed clinically by the Fugl-Meyer assessment scale for the upper extremity (FMA-UE). Forty-two first-event stroke patients in the subacute phase and 13 healthy controls of similar age participated in the study. Elbow motion was analyzed in the context of repeated reach-to-grasp movements towards four differently located targets. Log-BKLD and HD along with movement time, final elbow extension angle, mean elbow velocity, peak elbow velocity, and the number of velocity peaks of the elbow motion were computed.

Results

Upper limb kinematics in patients with lower FMA-UE scores (greater impairment) showed greater deviation from normality when the distance between impaired and normal elbow motion was analyzed either with the BKLD or HD measures. The severity of spasticity, reflected by the TSRT, was related to the distance between impaired and normal elbow motion analyzed with either distance measure. Mean elbow velocity differed between targets, however HD was not sensitive to target location. This may point at effects of spasticity on motion quality that go beyond effects on velocity.

Conclusions

The two methods for analyzing pathological movement post-stroke provide new options for studying the relationship between spasticity and movement quality under different spatiotemporal constraints.

A New Definition of Poststroke Spasticity and the Interference of Spasticity With Motor Recovery From Acute to Chronic Stages

The relationship of poststroke spasticity and motor recovery can be confusing. "True" motor recovery refers to return of motor behaviors to prestroke state with the same end-effectors and temporo-spatial pattern. This requires neural recovery and repair, and presumably occurs mainly in the acute and subacute stages. However, according to the International Classification of Functioning, Disability and Health, motor recovery after stroke is also defined as "improvement in performance of functional tasks," i.e., functional recovery, which is mainly mediated by compensatory mechanisms. Therefore, stroke survivors can execute motor tasks in spite of disordered motor control and the presence of spasticity. Spasticity interferes with execution of normal motor behaviors ("true" motor recovery), throughout the evolution of stroke from acute to chronic stages. Spasticity reduction does not affect functional recovery in the acute and subacute stages; however, appropriate management of spasticity could lead to improvement of motor function, that is, functional recovery, during the chronic stage of stroke. We assert that spasticity results from upregulation of medial cortico-reticulo-spinal pathways that are disinhibited due to damage of the motor cortex or corticobulbar pathways. Spasticity emerges as a manifestation of maladaptive plasticity in the early stages of recovery and can persist into the chronic stage. It coexists and shares similar pathophysiological processes with related motor impairments, such as abnormal force control, muscle coactivation and motor synergies, and diffuse interlimb muscle activation. Accordingly, we propose a new definition of spasticity to better account for its pathophysiology and the complex nuances of different definitions of motor recovery.

Remote Ischemic Conditioning and Stroke Recovery

Remote ischemic conditioning (RIC) is a noninvasive procedure whereby several periods of ischemia are induced in a limb. Although there is growing interest in using RIC to improve stroke recovery, preclinical RIC research has focused exclusively on neuroprotection, using male animals and the intraluminal suture stroke model, and delivered RIC at times not relevant to either brain repair or behavioral recovery. In alignment with the Stroke Recovery and Rehabilitation Roundtable, we address these shortcomings. First, a standardized session (5-minute inflation/deflation, 4 repetitions) of RIC was delivered using a cuff on the contralesional hindlimb in both male and female Sprague-Dawley rats. Using the endothelin-1 stroke model, RIC was delivered once either prestroke (18 hours before, pre-RIC) or poststroke (4 hours after, post-RIC), and infarct volume was assessed at 24 hours poststroke using magnetic resonance imaging. RIC was delivered at these times to mimic the day before a surgery where clots are possible or as a treatment similar to tissue plasminogen activator, respectively. Pre-RIC reduced infarct volume by 41% compared with 29% with post-RIC. RIC was neuroprotective in both sexes, but males had a 46% reduction of infarct volume compared with 23% in females. After confirming the acute efficacy of RIC, we applied it chronically for 4 weeks, beginning 5 days poststroke. This delayed RIC failed to enhance poststroke behavioral recovery. Based on these findings, the most promising application of RIC is during the hyperacute and early acute phases of stroke, a time when other interventions such as exercise may be contraindicated.

Early parietofrontal network upregulation relates to future persistent deficits after severe stroke-a prospective cohort study

Recent brain imaging has evidenced that parietofrontal networks show alterations after stroke which also relate to motor recovery processes. There is converging evidence for an upregulation of parietofrontal coupling between parietal brain regions and frontal motor cortices. The majority of studies though have included only moderately to mildly affected patients, particularly in the subacute or chronic stage. Whether these network alterations will also be present in severely affected patients and early after stroke and whether such information can improve correlative models to infer motor recovery remains unclear. In this prospective cohort study, 19 severely affected first-ever stroke patients (mean age 74 years, 12 females) were analysed which underwent resting-state functional MRI and clinical testing during the initial week after the event. Clinical evaluation of neurological and motor impairment as well as global disability was repeated after three and six months. Nineteen healthy participants of similar age and gender were also recruited. MRI data were used to calculate functional connectivity values between the ipsilesional primary motor cortex, the ventral premotor cortex, the supplementary motor area and the anterior and caudal intraparietal sulcus of the ipsilesional hemisphere. Linear regression models were estimated to compare parietofrontal functional connectivity between stroke patients and healthy controls and to relate them to motor recovery. The main finding was a significant increase in ipsilesional parietofrontal coupling between anterior intraparietal sulcus and the primary motor cortex in severely affected stroke patients (P < 0.003). This upregulation significantly contributed to correlative models explaining variability in subsequent neurological and global disability as quantified by National Institute of Health Stroke Scale and modified Rankin Scale, respectively. Patients with increased parietofrontal coupling in the acute stage showed higher levels of persistent deficits in the late subacute stage of recovery (P < 0.05). This study provides novel insights that parietofrontal networks of the ipsilesional hemisphere undergo neuroplastic alteration already very early after severe motor stroke. The association between early parietofrontal upregulation and future levels of persistent functional deficits and dependence from help in daily living might be useful in models to enhance clinical neurorehabilitative decision making.

"Rehabilitation Research Framework for Patients With COVID-19" Defined by Cochrane Rehabilitation and the World Health Organization Rehabilitation Programme

The coronavirus disease 2019 (COVID-19) pandemic resulted in a surge of research activity. Since its outset, efforts have been made to guide the rapid generation of research in medicine. There are gaps in some areas of rehabilitation research for patients with COVID-19. The development of a specific research framework might serve to help monitor the status of research (mapping), shape and strengthen research by pointing to under-investigated areas, and promote rehabilitation research in this context. This article introduces and discusses the COVID-19 Rehabilitation Research Framework (CRRF) and presents the methodology used for its development. The questions have been developed among the World Health Organization (WHO) Rehabilitation Programme, Cochrane Rehabilitation, and the experts of its Rehabilitation-COVID-19 Evidence-based Response Action International Multiprofessional Steering Committee. The framework is divided into 2 parts and includes 20 questions organized in 4 groups: epidemiology, and evidence at the micro- (individual), meso- (health services), and macro- (health systems) levels. The CRRF offers a comprehensive view of the research areas relevant to COVID-19 and rehabilitation that are necessary to inform best practice and ensure rehabilitation services and health systems can best serve the population with COVID-19. The collaboration between Cochrane Rehabilitation and the WHO Rehabilitation Programme in establishing the CRRF brought together perspectives from the health systems, health management, and clinical evidence. The authors encourage researchers to use the CRRF when planning studies on rehabilitation in the context of COVID-19.

A randomized controlled trial on the effects induced by robot-assisted and usual-care rehabilitation on upper limb muscle synergies in post-stroke subjects

Muscle synergies are hypothesized to reflect connections among motoneurons in the spinal cord activated by central commands and sensory feedback. Robotic rehabilitation of upper limb in post-stroke subjects has shown promising results in terms of improvement of arm function and motor control achieved by reassembling muscle synergies into a set more similar to that of healthy people. However, in stroke survivors the potentially neurophysiological changes induced by robot-mediated learning versus usual care have not yet been investigated. We quantified upper limb motor deficits and the changes induced by rehabilitation in 32 post-stroke subjects through the movement analysis of two virtual untrained tasks of object placing and pronation. The sample analyzed in this study is part of a larger bi-center study and included all subjects who underwent kinematic analysis and were randomized into robot and usual care groups. Post-stroke subjects who followed robotic rehabilitation showed larger improvements in axial-to-proximal muscle synergies with respect to those who underwent usual care. This was associated to a significant improvement of the proximal kinematics. Both treatments had negative effects in muscle synergies controlling the distal district. This study supports the definition of new rehabilitative treatments for improving the neurophysiological recovery after stroke.

A Robotic System with EMG-Triggered Functional Eletrical Stimulation for Restoring Arm Functions in Stroke Survivors

BACKGROUND

Robotic systems combined with Functional Electrical Stimulation (FES) showed promising results on upper-limb motor recovery after stroke, but adequately-sized randomized controlled trials (RCTs) are still missing.

OBJECTIVE

To evaluate whether arm training supported by RETRAINER, a passive exoskeleton integrated with electromyograph-triggered functional electrical stimulation, is superior to advanced conventional therapy (ACT) of equal intensity in the recovery of arm functions, dexterity, strength, activities of daily living, and quality of life after stroke.

METHODS

A single-blind RCT recruiting 72 patients was conducted. Patients, randomly allocated to 2 groups, were trained for 9 weeks, 3 times per week: the experimental group performed task-oriented exercises assisted by RETRAINER for 30 minutes plus ACT (60 minutes), whereas the control group performed only ACT (90 minutes). Patients were assessed before, soon after, and 1 month after the end of the intervention. Outcome measures were as follows: Action Research Arm Test (ARAT), Motricity Index, Motor Activity Log, Box and Blocks Test (BBT), Stroke Specific Quality of Life Scale (SSQoL), and Muscle Research Council.

RESULTS

All outcomes but SSQoL significantly improved over time in both groups (P < .001); a significant interaction effect in favor of the experimental group was found for ARAT and BBT. ARAT showed a between-group change of 11.5 points (P = .010) at the end of the intervention, which increased to 13.6 points 1 month after. Patients considered RETRAINER moderately usable (System Usability Score of 61.5 ± 22.8).

CONCLUSIONS

Hybrid robotic systems, allowing to perform personalized, intensive, and task-oriented training, with an enriched sensory feedback, was superior to ACT in improving arm functions and dexterity after stroke.

Effects of Robotic Therapy Associated With Noninvasive Brain Stimulation on Upper-Limb Rehabilitation After Stroke: Systematic Review and Meta-analysis of Randomized Clinical Trials

BACKGROUND

Robot-assisted therapy and noninvasive brain stimulation (NIBS) are promising strategies for stroke rehabilitation.

OBJECTIVE

This systematic review and meta-analysis aims to evaluate the evidence of NIBS as an add-on intervention to robotic therapy in order to improve outcomes of upper-limb motor impairment or activity in individuals with stroke.

METHODS

This study was performed according to the PRISMA Protocol and was previously registered on the PROSPERO Platform (CRD42017054563). Seven databases and gray literature were systematically searched by 2 reviewers, and 1176 registers were accessed. Eight randomized clinical trials with upper-limb body structure/function or activity limitation outcome measures were included. Subgroup analyses were performed according to phase poststroke, device characteristics (ie, arm support, joints involved, unimanual or bimanual training), NIBS paradigm, timing of stimulation, and number of sessions. The Grade-Pro Software was used to assess quality of the evidence.

RESULTS

A nonsignificant homogeneous summary effect size was found both for body structure function domain (mean difference [MD] = 0.15; 95% CI = -3.10 to 3.40; P = 0.93; I² = 0%) and activity limitation domain (standard MD = 0.03; 95% CI = -0.28 to 0.33; P = 0.87; I² = 0%).

CONCLUSIONS

According to this systematic review and meta-analysis, at the moment, there are not enough data about the benefits of NIBS as an add-on intervention to robot-assisted therapy on upper-limb motor function or activity in individuals with stroke.

Computerised patient-specific prediction of the recovery profile of upper limb capacity within stroke services: the next step

INTRODUCTION

Predicting upper limb capacity recovery is important to set treatment goals, select therapies and plan discharge. We introduce a prediction model of the patient-specific profile of upper limb capacity recovery up to 6 months poststroke by incorporating all serially assessed clinical information from patients.

METHODS

Model input was recovery profile of 450 patients with a first-ever ischaemic hemispheric stroke measured using the Action Research Arm Test (ARAT). Subjects received at least three assessment sessions, starting within the first week until 6 months poststroke. We developed mixed-effects models that are able to deal with one or multiple measurements per subject, measured at non-fixed time points. The prediction accuracy of the different models was established by a fivefold cross-validation procedure.

RESULTS

A model with only ARAT time course, finger extension and shoulder abduction performed as good as models with more covariates. For the final model, cross-validation prediction errors at 6 months poststroke decreased as the number of measurements per subject increased, from a median error of 8.4 points on the ARAT (Q1-Q3:1.7-28.1) when one measurement early poststroke was used, to 2.3 (Q1-Q3:1-7.2) for seven measurements. An online version of the recovery model was developed that can be linked to data acquisition environments.

CONCLUSION

Our innovative dynamic model can predict real-time, patient-specific upper limb capacity recovery profiles up to 6 months poststroke. The model can use all available serially assessed data in a flexible way, creating a prediction at any desired moment poststroke, stand-alone or linked with an electronic health record system.

Five Features to Look for in Early-Phase Clinical Intervention Studies

Neurorehabilitation relies on core principles of neuroplasticity to activate and engage latent neural connections, promote detour circuits, and reverse impairments. Clinical interventions incorporating these principles have been shown to promote recovery and demote compensation. However, many clinicians struggle to find interventions centered on these principles in our nascent, rapidly growing body of literature. Not to mention the immense pressure from regulatory bodies and organizational balance sheets that further discourage time-intensive recovery-promoting interventions, incentivizing clinicians to prioritize practical constraints over sound clinical decision making. Modern neurorehabilitation practices that result from these pressures favor strategies that encourage compensation over those that promote recovery. To narrow the gap between the busy clinician and the cutting-edge motor recovery literature, we distilled 5 features found in early-phase clinical intervention studies-ones that value the more enduring biological recovery processes over the more immediate compensatory remedies. Filtering emerging literature through this lens and routinely integrating promising research into daily practice can break down practical barriers for effective clinical translation and ultimately promote durable long-term outcomes. This perspective is meant to serve a new generation of mechanistically minded and caring clinicians, students, activists, and research trainees, who are poised to not only advance rehabilitation science, but also erect evidence-based policy changes to accelerate recovery-based stroke care.

Encouraging an excitable brain state: mechanisms of brain repair in stroke

Stroke induces a plastic state in the brain. This period of enhanced plasticity leads to the sprouting of new axons, the formation of new synapses and the remapping of sensory-motor functions, and is associated with motor recovery. This is a remarkable process in the adult brain, which is normally constrained in its levels of neuronal plasticity and connectional change. Recent evidence indicates that these changes are driven by molecular systems that underlie learning and memory, such as changes in cellular excitability during memory formation. This Review examines circuit changes after stroke, the shared mechanisms between memory formation and brain repair, the changes in neuronal excitability that underlie stroke recovery, and the molecular and pharmacological interventions that follow from these findings to promote motor recovery in animal models. From these findings, a framework emerges for understanding recovery after stroke, central to which is the concept of neuronal allocation to damaged circuits. The translation of the concepts discussed here to recovery in humans is underway in clinical trials for stroke recovery drugs.

Intra- and interrater reliability of Fugl-Meyer Assessment of Lower Extremity early after stroke

BACKGROUND

The Fugl-Meyer Assessment of Lower Extremity (FMA-LE) is a widely used and recommended scale for evaluation of post-stroke motor impairment. However, the reliability of the scale has only been established by using parametric statistical methods, which ignores the ordinal properties of the scale.

OBJECTIVE

To determined intra- and inter-rater reliability of the FMA-LE at item and summed score level early after stroke.

METHODS

Sixty patients (mean age 65.9 years, median FMA-LE 29 points) admitted to the hospital due to stroke were included. The FMA-LE was simultaneously, but independently, scored by three experienced and trained physical therapists randomly assigned into pairs, on two consecutive days, between 4 to 9 days post stroke. A rank-based statistical method for paired ordinal data was used to assess the level of agreement and systematic and random disagreements.

RESULTS

The item-level reliability was high (percentage of agreement [PA] ≥75%). Two items (ankle dorsiflexion during flexor synergy and normal reflex activity) showed some systematic disagreement in intrarater analysis. A satisfactory intrarater reliability (PA ≥70%) was reached for all summed scores when a 1- or 2-point difference was accepted between ratings.

CONCLUSION

The FMA-LE is a reliable tool for assessment of motor impairment both within and between raters early after stroke. The scale can be recommended not only for use in Spanish speaking countries, but also internationally. A unified international use of FMA-LE would allow comparison of stroke recovery outcomes worldwide and thereby potentially improve the quality of stroke rehabilitation.

SWEAT2 study: effectiveness of trunk training on muscle activity after stroke. A randomized controlled trial

BACKGROUND

Trunk training after stroke is an effective method for improving trunk control, standing balance and mobility. The SWEAT² study attempts to discover the underlying mechanisms leading to the observed mobility carry-over effects after trunk training.

AIM

A secondary analysis investigating the effect of trunk training on muscle activation patterns, muscle synergies and motor unit recruitment of trunk and lower limbs muscles, aimed to provide new insights in gait recovery after stroke.

DESIGN

Randomized controlled trial.

SETTING

Monocentric study performed in the RevArte Rehabilitation Hospital (Antwerp, Belgium).

POPULATION

Forty-five adults diagnosed with first stroke within five months, of which 39 completed treatment and were included in the analysis.

METHODS

Participants received 16 hours of additional trunk training (N.=19) or cognitive training (N.=20) over the course of four weeks (1 hour, 4 times a week). They were assessed by an instrumented gait analysis with electromyography of trunk and lower limb muscles. Outcome measures were linear integrated normalized envelopes of the electromyography signal, the amount and composition of muscle synergies calculated by nonnegative matrix factorization and motor unit recruitment calculated, by mean center wavelet frequencies. Multivariate analysis with post-hoc analysis and statistical parametric mapping of the continuous curves were performed.

RESULTS

No significant differences were found in muscle activation patterns and the amount of muscle synergies. In 42% of the subjects, trunk training resulted in an additional muscle synergy activating trunk muscles in isolation, as compared to 5% in the control group. Motor unit recruitment of the of trunk musculature showed decreased fast-twitch motor recruitment in the erector spinae muscle after trunk training: for the hemiplegic (t[37]=2.44, P=0.021) and non-hemiplegic erector spinae muscle (t[37]=2.36, P=0.024).

CONCLUSIONS

Trunk training improves selective control and endurance of trunk musculature after sub-acute stroke.

CLINICAL REHABILITATION IMPACT

What is new to the actual clinical rehabilitation knowledge is that: trunk training does not alter muscle activation patterns or the amount of muscle synergies over time; a decrease in fast-twitch motor recruitment in the erector spinae muscle was found during walking after trunk training; trunk training seems to increase the fatigue-resistance of the back muscles and enables more isolated activation.

Early clinical predictors of post stroke spasticity

Background and Purpose: Up to 40% of stroke patients with paresis develop post-stroke spasticity (PSS), which induces difficult complications including pain, contracture, posture disorder. The most important factor for PSS management is its early initiation, so that early recognition of PSS is required in clinical practice.Methods: This prospective observational cohort study was conducted with a high standard of PSS assessment and a comprehensive protocol investigating possible predictive factors to identify early predictors of PSS already in the acute phase following stroke (<7 days). PSS was assessed with the Resistance to Passive movement Scale (REPAS) for major joint movements in upper- and lower limbs, based on Ashworth scale, within 7 days following stroke and after 3 months. Binary logistic regression analysis with significant clinical parameters was applied with 95% of confidence intervals (CI) to find predictors of PSS.Results: Of 145 consecutive first-ever stroke patients, 34 patients (23.4%) exhibited PSS. The Modified Rankin Scale (MRS), National Institutes of Health Stroke Scale (NIHSS), and Mini-Mental State Examination (MMSE) were revealed as strong clinical predictors of PSS. The combination of an MRS >2 (Odds Ratio (OR): 56.538, 95% CI: 17.150-186.394), NIHSS >2 (OR: 57.137, 95% CI:15.685-208.142) and MMSE <27 (OR: 6.133, 95% CI:2.653-14.178) showed positive predictive (95.2%) value for prediction of PSS (sensitivity 94.4%, specificity 93.3%).Conclusions: Besides evaluating PSS itself with a reliable and valid rating scale the common clinical scales in stroke units practice (NIHSS, MRS, MMSE) allow early identification of patients at high risk for PSS.

Funktionserholung nach Schlaganfall und die therapeutische Rolle der nicht-invasiven Hirnstimulation

Im Bereich der non-invasiven Hirnstimulation stellen die transkranielle Magnetstimulation (engl. transcranial magnetic stimulation, TMS) sowie die transkranielle Gleichstromstimulation (engl. transcranial direct current stimulation, tDCS) bis heute die wichtigsten Techniken zur Modulation kortikaler Erregbarkeit dar. Beide Verfahren induzieren Nacheffekte, welche die Zeit der reinen Stimulation überdauern, und ebnen damit den Weg für ihren therapeutischen Einsatz beim Schlaganfall. In diesem Übersichtsartikel diskutieren wir die aktuelle Datenlage TMS- und tDCS-vermittelter Therapien für die häufigsten schlaganfallbedingten Defizite wie Hemiparese, Aphasie und Neglect. Darüber hinaus adressieren wir mögliche Einschränkungen der gegenwärtigen Ansätze und zeigen Ansatzpunkte auf, um Neuromodulation nach Schlaganfall effektiver zu gestalten und damit das Outcome der Patienten zu verbessern.

Systematic Review and Meta-Analysis of the Effectiveness of Mental Practice for the Upper Limb After Stroke: Imagined or Real Benefit?

OBJECTIVES

This systematic review sought to determine the effectiveness of mental practice (MP) on the activity limitations of the upper limb in individuals after stroke, as well as when, in whom, and how MP should be delivered.

DATA SOURCES

Ten electronic databases were searched from November 2009 to May 2020. Search terms included: Arm, Practice, Stroke rehabilitation, Imagination, Paresis, Recovery of function, and Stroke. Studies from a Cochrane review of MP (up to November 2009) were automatically included. The review was registered with the PROSPERO database of systematic reviews (reference no.: CRD42019126044).

STUDY SELECTION

Randomized controlled trials of adults after stroke using MP for the upper limb were included if they compared MP to usual care, conventional therapy, or no treatment and reported activity limitations of the upper limb as outcomes. Independent screening was conducted by 2 reviewers.

DATA EXTRACTION

One reviewer extracted data using a tool based on the Template for Intervention Description and Replication. Data extraction was independently verified by a second reviewer. Quality was assessed using the PEDro tool.

DATA SYNTHESIS

Fifteen studies (n=486) were included and 12 (n=328) underwent meta-analysis. MP demonstrated significant benefit on upper limb activities compared with usual treatment (standardized mean difference [SMD], 0.6; 95% confidence interval [CI], 0.32-0.88). Subgroup analyses demonstrated that MP was most effective in the first 3 months after stroke (SMD, 1.01; 95% CI, 0.53-1.50) and in individuals with the most severe upper limb deficits (weighted mean difference, 7.33; 95% CI, 0.94-13.72).

CONCLUSIONS

This review demonstrates that MP is effective in reducing activity limitations of the upper limb after stroke, particularly in the first 3 months after stroke and in individuals with the most severe upper limb dysfunction. There was no clear pattern of the ideal dosage of MP.

Dancing to improve balance control, cognitive-motor functions and quality of life after stroke: a study protocol for a randomised controlled trial

INTRODUCTION

Dance is an intrinsically motivating activity that includes social interaction, stimulation through music, the pleasure of moving despite pathology-induced motor limitations, and it also has good perceived benefits among participants. Feeling pleasure while moving is essential to finding the motivation to engage in a rehabilitation programme. It is, therefore, urgent to provide persons in a poststroke situation with motivating physical activity opportunities. Very few studies have examined dance in a stroke context, while it is highly adapted and effective for other chronic conditions.Our primary objective is to assess the effects of dance programme on patients' balance control after stroke. Our secondary objective is to investigate the effects of dance on cognitive function, strength, coordination, functional status, balance confidence, quality of life, motivation and adherence. Our hypothesis is that dance increases balance and motor capacities, and improves poststroke quality of life, adherence and motivation.

METHODS AND ANALYSIS

Forty-eight subjects with stroke in subacute phase will be randomised into two groups: (1) intervention (dance and standard rehabilitation) and (2) control (standard rehabilitation). Before intervention, stroke severity, cognitive abilities and motor capacities will be assessed. Two baseline tests will be planned to evaluate the stability of individuals. Participants will attend a weekly 60-min dance class for 6 weeks. Cognitive and motor functions (balance, lower-limbs strength, coordination and motor level), quality of life (Stroke-Specific Quality of Life Scale) will be measured at weeks 4 and 6 in both groups. Participant satisfaction with regard to dance will be tested, as well as adherence and adverse effects.

ETHICS AND DISSEMINATION

Ethics approval has been granted by the Swiss Ethics Committee of the CER Vaud (2019-01467). Outcomes will be disseminated through publication in peer-reviewed journals and presentations at conferences.

TRIAL REGISTRATION NUMBER

NCT04120467.

Reliability and validity of the incremental shuttle walking test in individuals after stroke

BACKGROUND

There are limitations to perform the cardiopulmonary exercise test (CPET) and the six-minute walking test (6MWT) in clinical settings. The incremental shuttle walking test (ISWT) might be an alternative assessment of exercise capacity and an estimation of cardiopulmonary fitness after stroke.

OBJECTIVES

To investigate the test-retest and inter-rater reliabilities, the standard error of measurement (SEM) and the minimal detectable change (MDC) of the ISWT, its construct validity to assess exercise capacity and its concurrent validity to estimate cardiopulmonary fitness after stroke.

METHODS

Prospective diagnostic accuracy study. Fifty-one individuals (54 ± 11 years) at the chronic phase (65 ± 73 months after stroke) were included. The distance walked, in meters, during the 12-stage-ISWT and the 6MWT and the peak oxygen uptake (VO_2peak, ml.kg^-1.min^-1) in the CPET (gold standard) were assessed.

RESULTS

Significant and high to very high magnitude test-retest and inter-rater reliabilities (0.88≤ICC≤0.93) of the ISWT was found. The SEM for both reliabilities was small (-23.35 m≤ SEM≤41.47 m). The MDC for test-retest and inter-rater reliabilities were 114.63 m and 64.53 m, respectively. For construct validity, a significant and high magnitude correlation between the ISWT and the 6MWT was found (ICC = 0.82). For the concurrent validity, a significant, but low magnitude correlation was found between the ISWT and the VO_2peak (rho = 0.42).

CONCLUSIONS

The ISWT demonstrated adequate reliabilities and construct validity for exercise capacity assessment. However, the concurrent validity of the ISWT as an estimation of cardiopulmonary fitness still requires further research.

SWEAT2 Study: Effectiveness of Trunk Training on Gait and Trunk Kinematics After Stroke: A Randomized Controlled Trial

OBJECTIVE

Trunk training after stroke is an effective method for improving mobility, yet underlying associations leading to the observed mobility carryover effects are unknown. The purposes of this study were to investigate the effectiveness of trunk training for gait and trunk kinematics and to find explanatory variables for the mobility carryover effects.

METHODS

This study was an assessor-masked, randomized controlled trial. Participants received either additional trunk training (n = 19) or cognitive training (n = 20) after subacute stroke. Outcome measures were the Tinetti Performance-Oriented Mobility Assessment (POMA), the Trunk Impairment Scale, spatiotemporal gait parameters, center-of-mass excursions, and trunk and lower limb kinematics during walking. Multivariate analysis with post hoc analysis was performed to observe treatment effects. Correlation and an exploratory regression analysis were used to examine associations with the mobility carryover effects.

RESULTS

Significant improvements after trunk training, compared with the findings for the control group, were found for the Trunk Impairment Scale, Tinetti POMA, walking speed, step length, step width, horizontal/vertical center-of-mass excursions, and trunk kinematics. No significant differences were observed in lower limb kinematics. Anteroposterior excursions of the trunk were associated with 30% of the variability in the mobility carryover effects.

CONCLUSIONS

Carryover effects of trunk control were present during ambulation. Decreased anteroposterior movements of the thorax were the main variable explaining higher scores on the Tinetti POMA Gait subscale. However, the implementation and generalizability of this treatment approach in a clinical setting are laborious and limited, necessitating further research.

IMPACT

Trunk training is an effective strategy for improving mobility after stroke. Regaining trunk control should be considered an important treatment goal early after stroke to adequately prepare patients for walking.

Neuronavigated 1 Hz rTMS of the left angular gyrus combined with visuospatial therapy in post-stroke neglect

BACKGROUND

Visuospatial neglect (VSN) may be caused by an inter-hemispheric imbalance of neural activity after brain injury. Repetitive transcranial magnetic stimulation (rTMS) allows rebalancing restoration to a certain degree, relieving neglect symptoms.

OBJECTIVE

This study investigates the therapeutic effect of 1 Hz rTMS applied over the left angular gyrus combined with visual scanning training in patients with left VSN in the subacute stroke phase.

METHODS

Twenty-eight patients with VSN were randomly assigned to either experimental (fifteen sessions of rTMS consisted of 1800 magnetic pulses delivered to the left angular gyrus with a neuronavigation control), or control group (fifteen sessions of sham stimulation), followed by visual scanning training. VSN severity was assessed both before and after treatment with a 3-month follow up employing the Behavioural Inattention Test and functional measures.

RESULTS

No statistically significant differences were detected in outcome measures between the rTMS and sham groups after completion of 3-week therapy and at 3-month follow up. The magnitude of stimulation effects was not associated either with lesion volume, its location, or baseline motor threshold.

CONCLUSIONS

Our study did not confirm efficacy of 1 Hz rTMS over the angular gyrus as an adjuvant method to visual scanning training in patients with VSN in the subacute stroke.

Recovery from stroke: current concepts and future perspectives

Stroke is a leading cause of acquired, permanent disability worldwide. Although the treatment of acute stroke has been improved considerably, the majority of patients to date are left disabled with a considerable impact on functional independence and quality of life. As the absolute number of stroke survivors is likely to further increase due to the demographic changes in our aging societies, new strategies are needed in order to improve neurorehabilitation. The most critical driver of functional recovery post-stroke is neural reorganization. For developing novel, neurobiologically informed strategies to promote recovery of function, an improved understanding of the mechanisms enabling plasticity and recovery is mandatory. This review provides a comprehensive survey of recent developments in the field of stroke recovery using neuroimaging and non-invasive brain stimulation. We discuss current concepts of how the brain reorganizes its functional architecture to overcome stroke-induced deficits, and also present evidence for maladaptive effects interfering with recovery. We demonstrate that the combination of neuroimaging and neurostimulation techniques allows a better understanding of how brain plasticity can be modulated to promote the reorganization of neural networks. Finally, neurotechnology-based treatment strategies allowing patient-tailored interventions to achieve enhanced treatment responses are discussed. The review also highlights important limitations of current models, and finally closes with possible solutions and future directions.

Machine Learning for 3D Kinematic Analysis of Movements in Neurorehabilitation

PURPOSE OF REVIEW

Recent advances in the machine learning field, especially in deep learning, provide the opportunity for automated, detailed, and unbiased analysis of motor behavior. Although there has not yet been wide use of these techniques in the motor rehabilitation field, they have great potential. In this review, I describe how the current state of machine learning can be applied to 3D kinematic analysis, and how this will have an impact on neurorehabilitation.

RECENT FINDINGS

Applications of deep learning methods, in the form of convolutional neural networks, have been revolutionary for image analysis such as face recognition and object detection in images, exceeding human level performance. Recent studies have shown applicability of these deep learning approaches to human posture and movement classification. It is to be expected that portable stereo-camera systems will bring 3D pose estimation into the clinical setting and allow the assessment of movement quality in response to interventions. Advances in machine learning can help automate the process of obtaining 3D kinematics of human movements and to identify/classify patterns of movement.

Functional preservation and enhanced capacity for visual restoration in subacute occipital stroke

Stroke damage to the primary visual cortex (V1) causes a loss of vision known as hemianopia or cortically-induced blindness. While perimetric visual field improvements can occur spontaneously in the first few months post-stroke, by 6 months post-stroke, the deficit is considered chronic and permanent. Despite evidence from sensorimotor stroke showing that early injury responses heighten neuroplastic potential, to date, visual rehabilitation research has focused on patients with chronic cortically-induced blindness. Consequently, little is known about the functional properties of the post-stroke visual system in the subacute period, nor do we know if these properties can be harnessed to enhance visual recovery. Here, for the first time, we show that 'conscious' visual discrimination abilities are often preserved inside subacute, perimetrically-defined blind fields, but they disappear by ∼6 months post-stroke. Complementing this discovery, we now show that training initiated subacutely can recover global motion discrimination and integration, as well as luminance detection perimetry, just as it does in chronic cortically-induced blindness. However, subacute recovery was attained six times faster; it also generalized to deeper, untrained regions of the blind field, and to other (untrained) aspects of motion perception, preventing their degradation upon reaching the chronic period. In contrast, untrained subacutes exhibited spontaneous improvements in luminance detection perimetry, but spontaneous recovery of motion discriminations was never observed. Thus, in cortically-induced blindness, the early post-stroke period appears characterized by gradual-rather than sudden-loss of visual processing. Subacute training stops this degradation, and is far more efficient at eliciting recovery than identical training in the chronic period. Finally, spontaneous visual improvements in subacutes were restricted to luminance detection; discrimination abilities only recovered following deliberate training. Our findings suggest that after V1 damage, rather than waiting for vision to stabilize, early training interventions may be key to maximize the system's potential for recovery.

Incidence of Free of Charge Physiotherapy in a Danish National Cohort of Stroke, Parkinson's Disease, Multiple Sclerosis and Rheumatoid Arthritis Patients

Background

Denmark is a welfare state with a publically funded healthcare system that includes the right to free of charge physiotherapy (FCP) for patients with chronic or progressive disease who fulfill strict criteria. The aim of this study was to investigate the incidence of referral to FCP in patients with a hospital diagnosis of stroke, multiple sclerosis (MS), Parkinson’s disease (PD) and rheumatoid arthritis (RA) between 2007 and 2016.

Methods

The study was register-based and included data from The Danish National Patient Registry and The National Health Service Registry. The study population included the four largest disease groups receiving FCP in Denmark. The incidence of receiving FCP was reported as the cumulated incidence proportion (CIP).

Results

The study showed that FCP was mainly initiated within the first 2 years after diagnosis. The 2-year CIP was 8% for stroke patients, 53% for PD patients, 49% for MS patients, and 16% for RA patients. The proportion of patients referred to FCP generally increased over the period of the study due to more patients being referred from medical specialists in primary care.

Conclusion

This study found substantial differences in the incidence of referral to FCP in a Danish population of stroke, PD, MS and RA patients.

Effects of robot therapy on upper body kinematics and arm function in persons post stroke: a pilot randomized controlled trial

BACKGROUND

Robot-based rehabilitation for persons post-stroke may improve arm function and daily-life activities as measured by clinical scales, but its effects on motor strategies during functional tasks are still poorly investigated. This study aimed at assessing the effects of robot-therapy versus arm-specific physiotherapy in persons post-stroke on motor strategies derived from upper body instrumented kinematic analysis, and on arm function measured by clinical scales.

METHODS

Forty persons in the sub-acute and chronic stage post-stroke were recruited. This sample included all those subjects, enrolled in a larger bi-center study, who underwent instrumented kinematic analysis and who were randomized in Center 2 into Robot (R_Group) and Control Group (C_Group). R_Group received robot-assisted training. C_Group received arm-specific treatment delivered by a physiotherapist. Pre- and post-training assessment included clinical scales and instrumented kinematic analysis of arm and trunk during a virtual untrained task simulating the transport of an object onto a shelf. Instrumented outcomes included shoulder/elbow coordination, elbow extension and trunk sagittal compensation. Clinical outcomes included Fugl-Meyer Motor Assessment of Upper Extremity (FM-UE), modified Ashworth Scale (MAS) and Functional Independence Measure (FIM).

RESULTS

R_Group showed larger post-training improvements of shoulder/elbow coordination (Cohen's d = - 0.81, p = 0.019), elbow extension (Cohen's d = - 0.71, p = 0.038), and trunk movement (Cohen's d = - 1.12, p = 0.002). Both groups showed comparable improvements in clinical scales, except proximal muscles MAS that decreased more in R_Group (Cohen's d = - 0.83, p = 0.018). Ancillary analyses on chronic subjects confirmed these results and revealed larger improvements after robot-therapy in the proximal portion of FM-UE (Cohen's d = 1.16, p = 0.019).

CONCLUSIONS

Robot-assisted rehabilitation was as effective as arm-specific physiotherapy in reducing arm impairment (FM-UE) in persons post-stroke, but it was more effective in improving motor control strategies adopted during an untrained task involving vertical movements not practiced during training. Specifically, robot therapy induced larger improvements of shoulder/elbow coordination and greater reduction of abnormal trunk sagittal movements. The beneficial effects of robot therapy seemed more pronounced in chronic subjects. Future studies on a larger sample should be performed to corroborate present findings.

TRIAL REGISTRATION

www.ClinicalTrials.gov NCT03530358. Registered 21 May 2018. Retrospectively registered.

Effects of Exercise Intensity on Acute Circulating Molecular Responses Poststroke

Background. Exercise intensity can influence functional recovery after stroke, but the mechanisms remain poorly understood. Objective. In chronic stroke, an intensity-dependent increase in circulating brain-derived neurotrophic factor (BDNF) was previously found during vigorous exercise. Using the same serum samples, this study tested acute effects of exercise intensity on other circulating molecules related to neuroplasticity, including vascular-endothelial growth factor (VEGF), insulin-like growth factor-1 (IGF1), and cortisol, with some updated analyses involving BDNF. Methods. Using a repeated-measures design, 16 participants with chronic stroke performed 3 exercise protocols in random order: treadmill high-intensity interval training (HIT-treadmill), seated-stepper HIT (HIT-stepper), and treadmill moderate-intensity continuous exercise (MCT-treadmill). Serum molecular changes were compared between protocols. Mediation and effect modification analyses were also performed. Results. VEGF significantly increased during HIT-treadmill, IGF1 increased during both HIT protocols and cortisol nonsignificantly decreased during each protocol. VEGF response was significantly greater for HIT-treadmill versus MCT-treadmill when controlling for baseline. Blood lactate positively mediated the effect of HIT on BDNF and cortisol. Peak treadmill speed positively mediated effects on BDNF and VEGF. Participants with comfortable gait speed ≥0.4 m/s had significantly lower VEGF and higher IGF1 responses, with a lower cortisol response during MCT-treadmill. Conclusions. BDNF and VEGF are promising serum molecules to include in future studies testing intensity-dependent mechanisms of exercise on neurologic recovery. Fast training speed and anaerobic intensity appear to be critical ingredients for eliciting these molecular responses. Serum molecular response differences between gait speed subgroups provide a possible biologic basis for previously observed differences in training responsiveness.

Effects of Transcranial Direct Current Stimulation (tDCS) and Exercises Treadmill on Autonomic Modulation of Hemiparetic Patients Due To Stroke-Clinic Test, Controlled, Randomized, Double-Blind

Background: After a Stroke, there is an autonomic nervous system (ANS) changes. Transcranial Direct Current Stimulation (tDCS) can promote the reorganization of the affected circuits.

Objective: To evaluate the effects of tDCS applied before a session of physical activity on the treadmill, in the modulation of the autonomic nervous system of post-stroke patients.

Methodology: Cross-over study, were randomized 12 adult hemiparetic subjects in 2 groups, Group 1 (active tDCS before exercise on the treadmill) and Group 2 (sham tDCS before exercise on the treadmill). Stimulation times were 20 min; treadmill time was 20 min. The heart rate variability (HRV) and Variability of Systolic Blood Pressure (VSBP) were evaluated for 15 min, in 3 periods (pre and post tDCS and during exercise recovery on the treadmill).

Results: There was no difference in the VSBP and the HRV between the groups, compared with the baseline data; however, in the intragroup analysis, the parasympathetic modulation after active tDCS increased by 18% over baseline by the RMSSD with IC 95% (−7.85 to −0.34). In group 1, the post-tDCS active and post-exercise periods presented a value of variance above baseline, indicating a better prognosis. In group 2, there was a significant reduction of 38% of Variance values (p = 0.003) after tDCS sham.

Conclusion: tDCS does not generate immediate effects on HRV and VSBP, except for intragroup comparison, which has greater participation in parasympathetic modulation in the group receiving active tDCS.

Defining Functional Therapy in Research Involving Children with Cerebral Palsy: A Systematic Review

Aim: To review definitions and elements of interventions in studies, which used the word "functional" to describe their intervention for children with cerebral palsy (CP), and to determine whether definitions and elements are similar to criteria of functional therapy described in the Dutch Guidelines.Methods: Systematic review of intervention studies, which used the word "functional" to describe interventions for children with CP. We described criteria of functional therapy that were used to describe the intervention, and whether criteria were described similarly to the descriptions used in the Dutch Guidelines.Results: Of the 27 included studies, criteria "based on the activities/participation level of the ICF-CY", "goal-directed" and "context-specific" were referred to the most (40-59.3%). Descriptions of these criteria were less comparable to the suggested definition (43.8-69.2%). The remaining three criteria ("active involvement", "task-specific", and "focused on functionality instead of normality") were referred to less frequently (18.5-33.3%). The descriptions reported for these criteria were, however, the most comparable with the suggested definitions (80-100%).Conclusions: The included studies, in general have not used criteria of functional therapy. Future studies have to describe the elements of interventions in detail. Moreover, it is important to reach consensus on the definition and elements of functional therapy.

Pediatric Stroke: Unique Implications of the Immature Brain on Injury and Recovery

Pediatric stroke causes significant morbidity for children resulting in lifelong neurological disability. Although hyperacute recanalization therapies are available for pediatric patients, most patients are ineligible for these treatments. Therefore the mainstay for pediatric stroke treatment relies on rehabilitation to improve outcomes. Little is known about the ideal rehabilitation therapies for pediatric patients with stroke and the unique interplay between the developing brain and our models of stroke recovery. In this review, we first discuss the consequences of pediatric stroke. Second, we examine the scientific evidence that exists between the mechanisms of recovery and how they are different in the pediatric developing brain. Finally, we evaluate potential interventions that could improve outcomes.

Electrical Stimulation in Lower Limb During Exercise to Improve Gait Speed and Functional Motor Ability 6 Months Poststroke. A Review with Meta-Analysis

INTRODUCTION

Stroke is the third most common cause of disability in adults over 65 years of age and there are 30.7 million survivors after stroke worldwide. Stroke survivors have the highest odds of reporting severe disability and the greatest variety of individual domains of disability compared to a range of other conditions. Electrical stimulation of peripheral sensory-motor systems increases voluntary movement and muscle strength and thereby raises the activities of daily living (ADL). Little is known about electrical stimulation during physical activity in rehabilitation; the objective of this review is therefore to investigate whether external electrical stimulation combined with activity improves functional motor ability and gait speed in patients who have experienced a stroke within the last 6 months.

METHODS

A review and random effects meta-analysis of randomized controlled clinical trials on gait speed and functional motor ability measured with Barthel Index (BI) and Bergs Balance Scale (BBS).

RESULTS

Eight trials were included (n = 191). Explorative meta-analysis was performed on gait speed (5 trials, n = 120), BI (3 trials, n = 74), and BBS (3 trial n = 79). A small, significant difference on gait speed 0.15 (95% confidence interval [CI]: 0.08-0.21) m/s, but no difference in BI 2.88 (95 % CI: -3.3 to 9.07) and BBS 1.73 (95% CI: -2.8 to 6.27).

CONCLUSIONS

Sparse, low-quality evidence indicates that electrical stimulation combined with activity is a relevant intervention to improve ADL within 6 months poststroke.

A Role for the Action Observation Network in Apraxia After Stroke

Limb apraxia is a syndrome often observed after stroke that affects the ability to perform skilled actions despite intact elementary motor and sensory systems. In a large cohort of unselected stroke patients with lesions to the left, right, and bilateral hemispheres, we used voxel-based lesion-symptom mapping (VLSM) on clinical CT head images to identify the neuroanatomical correlates of the impairment of performance in three tasks investigating praxis skills in patient populations. These included a meaningless gesture imitation task, a gesture production task involving pantomiming transitive and intransitive gestures, and a gesture recognition task involving recognition of these same categories of gestures. Neocortical lesions associated with poor performance in these tasks were all in the left hemisphere. They involved the pre-striate and medial temporal cortices, the superior temporal sulcus, inferior parietal area PGi, the superior longitudinal fasciculus underlying the primary motor cortex, and the uncinate fasciculus, subserving connections between temporal and frontal regions. No significant lesions were identified when language deficits, as indicated via a picture naming task, were controlled for. The implication of the superior temporal sulcus and the anatomically connected prestriate and inferior parietal regions challenges traditional models of the disorder. The network identified has been implicated in studies of action observation, which might share cognitive functions sub-serving praxis and language skills.

Gait Asymmetry Post-Stroke: Determining Valid and Reliable Methods Using a Single Accelerometer Located on the Trunk

Asymmetry is a cardinal symptom of gait post-stroke that is targeted during rehabilitation. Technological developments have allowed accelerometers to be a feasible tool to provide digital gait variables. Many acceleration-derived variables are proposed to measure gait asymmetry. Despite a need for accurate calculation, no consensus exists for what is the most valid and reliable variable. Using an instrumented walkway (GaitRite) as the reference standard, this study compared the validity and reliability of multiple acceleration-derived asymmetry variables. Twenty-five post-stroke participants performed repeated walks over GaitRite whilst wearing a tri-axial accelerometer (Axivity AX3) on their lower back, on two occasions, one week apart. Harmonic ratio, autocorrelation, gait symmetry index, phase plots, acceleration, and jerk root mean square were calculated from the acceleration signals. Test-retest reliability was calculated, and concurrent validity was estimated by comparison with GaitRite. The strongest concurrent validity was obtained from step regularity from the vertical signal, which also recorded excellent test-retest reliability (Spearman's rank correlation coefficients (rho) = 0.87 and Intraclass correlation coefficient (ICC21) = 0.98, respectively). Future research should test the responsiveness of this and other step asymmetry variables to quantify change during recovery and the effect of rehabilitative interventions for consideration as digital biomarkers to quantify gait asymmetry.

Wearable technology in stroke rehabilitation: towards improved diagnosis and treatment of upper-limb motor impairment

Stroke is one of the main causes of long-term disability worldwide, placing a large burden on individuals and society. Rehabilitation after stroke consists of an iterative process involving assessments and specialized training, aspects often constrained by limited resources of healthcare centers. Wearable technology has the potential to objectively assess and monitor patients inside and outside clinical environments, enabling a more detailed evaluation of the impairment and allowing the individualization of rehabilitation therapies. The present review aims to provide an overview of wearable sensors used in stroke rehabilitation research, with a particular focus on the upper extremity. We summarize results obtained by current research using a variety of wearable sensors and use them to critically discuss challenges and opportunities in the ongoing effort towards reliable and accessible tools for stroke rehabilitation. Finally, suggestions concerning data acquisition and processing to guide future studies performed by clinicians and engineers alike are provided.

Low-Frequency Brain Oscillations Track Motor Recovery in Human Stroke

OBJECTIVE

The majority of patients with stroke survive the acute episode and live with enduring disability. Effective therapies to support recovery of motor function after stroke are yet to be developed. Key to this development is the identification of neurophysiologic signals that mark recovery and are suitable and susceptible to interventional therapies. Movement preparatory low-frequency oscillations (LFOs) play a key role in cortical control of movement. Recent animal data point to a mechanistic role of motor cortical LFOs in stroke motor deficits and demonstrate neuromodulation intervention with therapeutic benefit. Their relevance in human stroke pathophysiology is unknown.

METHODS

We studied the relationship between movement-preparatory LFOs during the performance of a visuomotor grip task and motor function in a longitudinal (<5 days, 1 and 3 months) cohort study of 33 patients with motor stroke and in 19 healthy volunteers.

RESULTS

Acute stroke-lesioned brains fail to generate the LFO signal. Whereas in healthy humans, a transient occurrence of LFOs preceded movement onset at predominantly contralateral frontoparietal motor regions, recordings in patients revealed that movement-preparatory LFOs were substantially diminished to a level of 38% after acute stroke. LFOs progressively increased at 1 and 3 months. This re-emergence closely tracked the recovery of motor function across several movement qualities including grip strength, fine motor skills, and synergies and was frequency band specific.

INTERPRETATION

Our results provide the first human evidence for a link between movement-preparatory LFOs and functional recovery after stroke, promoting their relevance for movement control. These results suggest that it may be interesting to explore targeted, LFOs-restorative brain stimulation therapy in human stroke patients. ANN NEUROL 2019;86:853-865.

Interventions for preventing falls in people after stroke

BACKGROUND

Falls are one of the most common complications after stroke, with a reported incidence ranging between 7% in the first week and 73% in the first year post stroke. This is an updated version of the original Cochrane Review published in 2013.

OBJECTIVES

To evaluate the effectiveness of interventions aimed at preventing falls in people after stroke. Our primary objective was to determine the effect of interventions on the rate of falls (number of falls per person-year) and the number of fallers. Our secondary objectives were to determine the effects of interventions aimed at preventing falls on 1) the number of fall-related fractures; 2) the number of fall-related hospital admissions; 3) near-fall events; 4) economic evaluation; 5) quality of life; and 6) adverse effects of the interventions.

SEARCH METHODS

We searched the trials registers of the Cochrane Stroke Group (September 2018) and the Cochrane Bone, Joint and Muscle Trauma Group (October 2018); the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 9) in the Cochrane Library; MEDLINE (1950 to September 2018); Embase (1980 to September 2018); CINAHL (1982 to September 2018); PsycINFO (1806 to August 2018); AMED (1985 to December 2017); and PEDro (September 2018). We also searched trials registers and checked reference lists.

SELECTION CRITERIA

Randomised controlled trials of interventions where the primary or secondary aim was to prevent falls in people after stroke.

DATA COLLECTION AND ANALYSIS

Two review authors (SD and WS) independently selected studies for inclusion, assessed trial quality and risk of bias, and extracted data. We resolved disagreements through discussion, and contacted study authors for additional information where required. We used a rate ratio and 95% confidence interval (CI) to compare the rate of falls (e.g. falls per person-year) between intervention and control groups. For risk of falling we used a risk ratio and 95% CI based on the number of people falling (fallers) in each group. We pooled results where appropriate and applied GRADE to assess the quality of the evidence.

MAIN RESULTS

We included 14 studies (of which six have been published since the first version of this review in 2013), with a total of 1358 participants. We found studies that investigated exercises, predischarge home visits for hospitalised patients, the provision of single lens distance vision glasses instead of multifocal glasses, a servo-assistive rollator and non-invasive brain stimulation for preventing falls.Exercise compared to control for preventing falls in people after strokeThe pooled result of eight studies showed that exercise may reduce the rate of falls but we are uncertain about this result (rate ratio 0.72, 95% CI 0.54 to 0.94, 765 participants, low-quality evidence). Sensitivity analysis for single exercise interventions, omitting studies using multiple/multifactorial interventions, also found that exercise may reduce the rate of falls (rate ratio 0.66, 95% CI 0.50 to 0.87, 626 participants). Sensitivity analysis for the effect in the chronic phase post stroke resulted in little or no difference in rate of falls (rate ratio 0.58, 95% CI 0.31 to 1.12, 205 participants). A sensitivity analysis including only studies with low risk of bias found little or no difference in rate of falls (rate ratio 0.88, 95% CI 0.65 to 1.20, 462 participants). Methodological limitations mean that we have very low confidence in the results of these sensitivity analyses.For the outcome of number of fallers, we are very uncertain of the effect of exercises compared to the control condition, based on the pooled result of 10 studies (risk ratio 1.03, 95% CI 0.90 to 1.19, 969 participants, very low quality evidence). The same sensitivity analyses as described above gives us very low certainty that there are little or no differences in number of fallers (single interventions: risk ratio 1.09, 95% CI 0.93 to 1.28, 796 participants; chronic phase post stroke: risk ratio 0.94, 95% CI 0.73 to 1.22, 375 participants; low risk of bias studies: risk ratio 0.96, 95% CI 0.77 to 1.21, 462 participants).Other interventions for preventing falls in people after strokeWe are very uncertain whether interventions other than exercise reduce the rate of falls or number of fallers. We identified very low certainty evidence when investigating the effect of predischarge home visits (rate ratio 0.85, 95% CI 0.43 to 1.69; risk ratio 1.48, 95% CI 0.71 to 3.09; 85 participants), provision of single lens distance glasses to regular wearers of multifocal glasses (rate ratio 1.08, 95% CI 0.52 to 2.25; risk ratio 0.74, 95% CI 0.47 to 1.18; 46 participants) and a servo-assistive rollator (rate ratio 0.44, 95% CI 0.16 to 1.21; risk ratio 0.44, 95% CI 0.16 to 1.22; 42 participants).Finally, transcranial direct current stimulation (tDCS) was used in one study to examine the effect on falls post stroke. We have low certainty that active tDCS may reduce the number of fallers compared to sham tDCS (risk ratio 0.30, 95% CI 0.14 to 0.63; 60 participants).

AUTHORS' CONCLUSIONS

At present there exists very little evidence about interventions other than exercises to reduce falling post stroke. Low to very low quality evidence exists that this population benefits from exercises to prevent falls, but not to reduce number of fallers.Fall research does not in general or consistently follow methodological gold standards, especially with regard to fall definition and time post stroke. More well-reported, adequately-powered research should further establish the value of exercises in reducing falling, in particular per phase, post stroke.

High Intensity Exercise for Walking Competency in Individuals with Stroke: A Systematic Review and Meta-Analysis

OBJECTIVE

To assess the effects of high intensity exercise on walking competency in individuals with stroke.

DATA SOURCES

A systematic electronic searching of the PubMed, EMBASE, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL (EBSCOhost), and SPORTSDiscus (EBSCOhost) was initially performed up to June 25, 2019.

STUDY SELECTION

Randomized controlled trials or clinical controlled trials comparing any walking or gait parameters of the high intensity exercise to lower intensity exercise or usual physical activities were included. The risk of bias of included studies was assessed by the Cochrane risk of bias tool. The quality of evidence was assessed using GRADE (Grading of Recommendations, Assessment, Development and Evaluation) system.

DATA EXTRACTION

Data were extracted by 2 independent coders. The mean and standard deviation of the baseline and endpoint scores after training for walking distance, comfortable gait speed, gait analysis (cadence, stride length, and the gait symmetry), cost of walking, Berg Balance Scale , Time Up&Go (TUG) Test and adverse events were extracted.

DATA SYNTHESIS

A total of 22 (n = 952) studies were included. Standardized mean difference (SMD), weighted mean difference (WMD), and odds ratios (ORs) were used to compute effect size and subgroup analysis was conducted to test the consistency of results with different characteristics of exercise and time since stroke. Sensitivity analysis was used to assess the robustness of the results, which revealed significant differences on walking distance (SMD = .32, 95% CI, .17-.46, P < .01, I² = 39%; WMD = 21.76 m), comfortable gait speed (SMD = .28, 95% CI, .06-.49, P = .01, I² = 47%; WMD = .04 m/s), stride length (SMD = .51, 95% CI, .13-.88, P < .01, I² = 0%; WMD = .12 m) and TUG (SMD = -.36, 95% CI, -.72 to .01, P = .05, I² = 9%; WMD = -1.89 s) in favor of high intensity exercise versus control group. No significant differences were found between the high intensity exercise and control group in adverse events, including falls (OR = 1.40, 95% CI, .69-2.85, P = .35, I² = 11%), pain (OR = 3.34, 95% CI, .82-13.51, P = .09, I² = 0%), and skin injuries (OR = 1.08, 95% CI, .30-3.90, P = .90, I² = 0%).

CONCLUSIONS

This systematic review suggests that high intensity exercise could be safe and more potent stimulus in enhancing walking competency in stroke survivors, with a capacity to improve walking distance, comfortable gait speed, stride length, and TUG compared with low to moderate intensity exercise or usual physical activities.

A multimodal training with visual biofeedback in subacute stroke survivors: a randomized controlled trial

BACKGROUND

Early interventions maximizing patient's involvement are essential to promote gait restoration and motor recovery after stroke.

AIM

The aim of this study is to evaluate the effects of a multimodal biofeedback training involving cycling augmented by functional electrical stimulation (FES) and balance exercises on walking ability and motor recovery.

DESIGN

Randomized controlled trial (NCT02439515).

SETTING

Inpatient rehabilitation facility.

POPULATION

Subacute stroke survivors (less than 6 months from the first event) aged up to 90 years old.

METHODS

Sixty-eight participants were randomly allocated to an experimental group, performing 15 sessions of biofeedback FES-cycling training followed by 15 sessions of biofeedback balance training (20 minutes each) in addition to usual care (70 minutes), and a control group performing 30 sessions (90 minutes) of usual care. Participants were evaluated before training, after 15 sessions, after 30 sessions, and at 6-month follow-up through: gait speed (primary outcome), spatiotemporal gait parameters, Six-Minute Walking Test, Functional Independence Measure, Motricity Index, Trunk Control Test, Berg Balance Scale, and Fall Efficacy Scale.

RESULTS

Both groups significantly improved over time, but no group and interaction effects were found for any outcomes. The 73% of the experimental group achieved a clinically meaningful change in gait speed compared to the 38% of the control group (P=0.048). These percentages were even more unbalanced for patients with a moderate to severe gait impairment at baseline (91% versus 36%; P=0.008).

CONCLUSIONS

The multimodal biofeedback training was not statistically superior to usual care, showing only a positive trend in favor of the experimental group on locomotion recovery. Patients initially not able to walk might be the best candidates for such a training.

CLINICAL REHABILITATION IMPACT

The multimodal biofeedback training is a task-specific, repetitive and intensive training requiring a minimal supervision, which might result in a lower staff to patient ratio if organized in group sessions. Therefore, it can represent a good alternative for early stroke rehabilitation.

Impaired Motor Function in the Affected Arm Predicts Impaired Postural Balance After Stroke: A Cross Sectional Study

Background: Impaired postural balance is a common symptom after stroke and a common cause of falling. Most common daily tasks use arm and hand movements. Impairment in an upper extremity is a common stroke symptom, affecting 50–80% in the acute phase after stroke, and 40–50% in the sub-acute phase. The impact of leg function on postural balance has been investigated in several studies, but few have stressed the importance of arm function on postural balance.

Objective: To explore whether there is any association between arm function and postural balance after stroke.

Method: A cross sectional study where 121 adults (mean age: 70 ± 12.3 years, 72 men) from two different data sources, Gothenburg Very Early Supported Discharge (GOTVED), and a study by Carvalho et al. were merged. Time for assessments ranged from 1 to 13 years when the patients were in the chronic phase. The dependent variables were Berg Balance scale (BBS) and Time Up and Go (TUG) both dichotomized to “impaired postural balance” and “not impaired postural balance.” As independent variables, the Fugl-Meyer Assessment-Upper Extremity (FMA-UE) scale was used. The FMA-UE was presented with the total score.

Results: The motor function in the arm affected after stroke onset correlated with postural balance both measured with the BBS (0.321, p < 0.001) and the TUG (−0.315, p = 0.001). Having impaired motor function in the arm was significantly associated with impaired postural balance assessed with the BBS with OR = 0.879 (CI 0.826–0.934, p < 0.001). Regression analysis with the TUG showed the same result, OR = 0.868 (CI 0.813–0.927, p < 0.001) for FM-UE.

Conclusion: The motor function of the affected arm was significantly associated with impaired postural balance post stroke, as assessed by BBS or TUG. It could be of clinical importance to be aware of the fact that not only lower extremity impairment, but also arm function can have an impact on postural balance in a late stage after stroke.

Trial Registration: VGFOUGSB-669501.

Effect of high-intensity exercise on cardiorespiratory fitness in stroke survivors: A systematic review and meta-analysis

BACKGROUND

Knowledge of the optimal protocol and safety of particularly high-intensity exercise applied to individuals with stroke is lacking.

OBJECTIVE

This systematic review and meta-analysis aimed to investigate the effect of high-intensity exercise on cardiorespiratory fitness in stroke survivors.

METHODS

We performed a systematic electronic search for articles in MedLine via PubMed, EMBASE, Web of Science, Cochrane Central Register of Controlled Trials, CINAHL, and SPORTSDiscus up to April 1, 2019. Peak oxygen consumption (VO₂peak), 6-min walk test (6MWT), fastest 10-m walk test (10MWT), and adverse events were assessed. The standardized mean difference (SMD), weighted mean difference (WMD), and odds ratios (ORs) were used to compute the effect size, and subgroup analysis was conducted to test the consistency of results as well as sensitivity analysis to assess the robustness of the results. The quality of evidence was assessed with the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system.

RESULTS

We included 17 studies (PEDro score≥4) in the meta-analysis. Post-intervention, high-intensity exercise had a significant effect on peak oxygen uptake (VO₂peak; SMD=0.56, P<0.01, I²=8%; WMD=2.53mL/kg/min; high quality of evidence) and 6MWT (SMD=0.26, P<0.01, I²=40%; WMD=17.08m; moderate quality of evidence) but not fastest 10MWT (SMD=0.33, P=0.27, I²=77%; WMD=0.05m/s; low quality of evidence). Subgroup analysis showed better effects of higher-intensity treadmill training (≥70% heart rate reserve/VO₂peak) for a longer duration (≥12 weeks) on VO₂peak and 6MWT in sub-acute or chronic stroke survivors. The high-intensity exercise and control groups did not differ in adverse events including falls [odds ratio (OR) 1.40, P=0.35, I²=11%; low quality of evidence], pain (OR 3.34, P=0.09, I²=0%; moderate quality of evidence), or skin injuries (OR 1.08, P=0.90, I²=0%; low quality of evidence).

CONCLUSIONS

Our meta-analysis suggests that high-intensity exercise is beneficial for cardiorespiratory fitness in stroke survivors and might be safe as a novel intervention in cardiopulmonary rehabilitation after stroke.

Daytime physical activity at admission is associated with improvement of gait independence 1 month later in people with subacute stroke: a longitudinal study

Background: Little is known about the benefits of daytime physical activity on gait ability in subacute stroke.Objectives: We investigated association between daytime physical activity at hospital admission and improvement of gait independence 1 month later in subacute stroke.Methods: Thirty-four participants with subacute stroke who could not walk independently were assessed. An accelerometer (HJA 350-IT, OMRON) was used to record the mean duration of light-intensity physical activity (LIPA) and moderate-to-vigorous-intensity physical activity (MVPA). LIPA and MVPA were recorded for 12 h per day for 7 consecutive days, and at three different time periods (daytime, therapy time, non-therapy time) at rehabilitation hospital admission (baseline). Gait independence was assessed by the functional ambulation category (FAC) at baseline and 1 month later. Participants were categorized into two groups based on the change of gait independence, as follows: the improved group, in which the FAC increased by ≥1; the non-improved group, in which the FAC did not increase.Results: Compared with the non-improved group, the improved group demonstrated significantly higher values of all physical activity variables, except for non-therapy time MVPA (p < .05). Logistic regression analysis showed that higher daytime LIPA was significantly associated with FAC improvement (OR = 1.068, 95% CI 1.009 to 1.140). In particular, higher non-therapy time LIPA was closely associated with FAC improvement (OR = 1.253, 95% CI 1.002 to 1.568).Conclusions: To promote recovery of gait independence in first month from admission, increasing daytime physical activity, especially LIPA during daytime or non-therapy time, is an important treatment target in subacute stroke.

A combination of multimodal physical exercises in real and virtual environments for individuals after chronic stroke: study protocol for a randomized controlled trial

Background

Multimodal physical exercises already have well-established benefits for the post-stroke population that influence gait functional capacity, balance, gait, cognition, and quality of life. This type of intervention can be performed in both real and virtual environments. Considering the characteristics of both environments, it is questioned to what extent the combination of interventions in real and virtual environments could result in improvement in post-stroke impairments.

Methods/design

We will conduct a randomized clinical trial with three groups: a real multimodal group (RMG), a virtual multimodal group (VMG), and a combined multimodal group (CMG). It was estimated that we will need a sample of 36 participants (12 per group). RMG individuals will only perform multimodal physical exercises in a real environment two times per week for 60 min per session for 15 weeks. VMG individuals will perform exercises of the same duration over the same time frame but only in a virtual environment. CMG individuals will hold a weekly session in a real environment and another weekly session in virtual environment. The primary outcome measure will be health-related quality of life, evaluated using the Stroke Impact Scale; effects on cognition (Montreal Cognitive Assessment), balance (Berg Balance Scale), mobility (Timed Up & Go), self-selected gait speed (10-meter walk test), and gait functional capacity (6-min walk test) will be investigated as secondary outcome measures. Participants will be evaluated before the beginning of the intervention, immediately after the end of the intervention, and at 1-month follow-up without exercise. If the data meet the assumptions of the parametric analysis, the results will be evaluated by analysis of variance (3 × 3) for the group factor, with repeated measures while taking into account the time factor. The post hoc Tukey test will be used to detect differences (α = 0.05).

Discussion

This study represents the first clinical trial to include three groups considering physical exercise in real and virtual environments, isolated and combined, that counterbalances the intensity and volume of training in all groups. This study also includes a control of progression in all groups along the 15-week intervention. The outcome measures are innovative because, according to International Classification of Functioning, Disability and Health, activity and participation are the targets for effectiveness evaluation.

Trial registration

Combinação de exercícios físicos multimodais em ambientes real e virtual para indivíduos pós acidente vascular cerebral crônico, RBR-4pt72m. Registered on 29 August 2016.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3396-2) contains supplementary material, which is available to authorized users.

PULSE-I - Is rePetitive Upper Limb SEnsory stimulation early after stroke feasible and acceptable? A stratified single-blinded randomised controlled feasibility study

BACKGROUND

Reduction in sensorimotor function of the upper limb is a common and persistent impairment after stroke, and less than half of stroke survivors recover even basic function of the upper limb after a year. Previous work in stroke has shown that repetitive sensory stimulation (RSS) of the upper limb may benefit motor function. As yet, there have been no investigations of RSS in the early-acute period despite this being the time window during which the neuroplastic processes underpinning sensorimotor recovery are likely to occur.

METHODS

A single-blinded, stratified, randomised controlled feasibility study was undertaken at two NHS acute trusts to determine the recruitment rate, intervention adherence, and safety and acceptability of an RSS intervention in the early period after stroke. Participants were recruited within 2 weeks of index stroke. Stratified on arm function, they were randomised to receive either 45 min of daily RSS and usual care or usual care alone (UC) for 2 weeks. Changes from baseline on the primary outcome of the Action Research Arm Test (ARAT) to measurements taken by a blinded assessor were examined after completion of the intervention (2 weeks) and at 3 months from randomisation.

RESULTS

Forty patients were recruited and randomised (RSS n = 23; UC n = 17) with a recruitment rate of 9.5% (40/417) of patients admitted with a stroke of which 52 (12.5%) were potentially eligible, with 10 declining to participate for various reasons. Participants found the RSS intervention acceptable and adherence was good. The intervention was safe and there were no serious adverse events.

CONCLUSIONS

This study indicates that recruitment to a trial of RSS in the acute period after stroke is feasible. The intervention was well tolerated and appeared to provide additional benefit to usual care. In addition to a definitive trial of efficacy, further work is warranted to examine the effects of varying doses of RSS upon arm function and the mechanism by which RSS induces sensorimotor recovery in the acute period after stroke.

TRIAL REGISTRATION

ISRCTN, registry no: ISRCTN17422343 ; IRAS Project ID: 215137. Registered on October 2016.

Lower serum free triiodothyronine levels are associated with symptoms of depression after ischemic stroke

OBJECTIVE

Anxiety and depression symptoms are common after stroke. Changes in thyroid axis hormones have been reported to contribute to these symptoms in clinically euthyroid subjects with and without adjacent somatic pathology. This study aimed to determine associations between serum thyroid axis hormone levels, depression and anxiety symptoms in patients who experienced acute ischemic stroke (AIS).

METHODS

In total, 169 patients participated in the study. Serum thyroid stimulating hormone, free tetraiodothyronine (FT4) and free triiodothyronine (FT3) levels were assayed on admission and upon discharge from the hospital. Screening for anxiety and depression symptoms was performed with the Hospital Anxiety and Depression Scale twice - while in the hospital and at the end of rehabilitation course.

RESULTS

In the acute period after AIS, 19.2% of all patients showed symptoms of anxiety and 26.0% - symptoms of depression, while during the subacute period these proportions have increased up to 30.3% and 32.6%. No significant associations between thyroid axis hormones and anxiety were determined for both periods. Serum FT3 levels and FT3/FT4 ratio on admission were significantly lower in patients with symptoms of depression compared to those without. After controlling for possible confounders, lower serum FT3 levels remained significantly associated with higher odds of depression in the acute (OR = 1.85; 95% CI: 1.05-3.23, p = 0.03) and subacute periods (OR = 2.50; 95% CI: 1.06-5.88, p = 0.04) after AIS.

CONCLUSIONS

FT3 serum levels on admission while in the hospital as well as at the end of rehabilitation course may predict post-stroke depression symptoms.

Brain Activations During Optokinetic Stimulation in Acute Right-Hemisphere Stroke Patients and Hemispatial Neglect: An fMRI Study

Objective. Leftward optokinetic stimulation (OKS) is a promising therapeutic approach for right-hemisphere stroke patients with left hemispatial neglect. We questioned whether the putative neural basis is an activation of frontoparietal brain regions involved in the control of eye movements and spatial attention. Methods. We used functional magnetic resonance imaging to investigate brain activations during OKS in acute right-hemisphere stroke patients (RHS, n = 19) compared with healthy control subjects (HC, n = 9). Based on neuropsychological testing we determined the ipsilesional attention bias in all RHS patients, 11 showed manifest hemispatial neglect. Results. In HC subjects, OKS in either direction led to bilateral activation of the visual cortex (V1-V4), frontal (FEF) and supplementary (SEF) eye fields, intraparietal sulcus (IPS), basal ganglia, and thalamus. RHS patients' activations were generally reduced compared with HC. Nevertheless, leftward OKS bilaterally activated the visual cortex (V1-V4), FEF, SEF, IPS, and thalamus. The neural response to OKS was negatively correlated with patients' behavioral impairment: The greater the individual attention bias/neglect the weaker the brain activations. Conclusion. In RHS patients, leftward OKS activates frontoparietal regions (FEF, IPS) that are spared from structural brain damage and functionally involved in both oculomotor control and spatial attention. This may provide a neural basis for the known therapeutic effects of OKS on hemispatial neglect. In acute stroke stages, reduced activation levels correlating with neglect severity indicate functional downregulation of the underlying dorsal attention network. Therefore, chronic RHS patients with less severe neglect after recovery of network disturbances may be more suitable candidates for OKS rehabilitation.

Dosage Matters

Background and Purpose- For stroke rehabilitation, task-specific training in animal models and human rehabilitation trials is considered important to modulate neuroplasticity, promote motor learning, and functional recovery. Little is known about what constitutes an effective dosage of therapy. Methods- This is a parallel group, 4 arms, single-blind, phase IIb, randomized controlled trial of 4 dosages of arm therapy delivered in an outpatient setting chronically after stroke. Participants were randomized into groups that varied in duration of scheduled therapy (ie, 0, 15, 30, or 60 hours). Forty-one participants completed the study. Planned primary analyses used linear mixed effects regression to model changes from baseline to postintervention in the Motor Activity Log-Quality of Movement rating and the Wolf Motor Function Test time score over 3 weeks of training as a function of therapy dosage. Results- We observed a dose response for the Motor Activity Log-Quality of Movement: the model that included dose and dose by week interaction significantly better fit the data than the model that included week only (log-likelihood test, P=0.0026). In addition, the greater the dosage of training, the greater the change in Motor Activity Log-Quality of Movement, with the dose by week interaction parameter equal to 0.0045 ( P=0.0016; 95% CI, 0.0018-0.0071). Over the 3 weeks of therapy, there was a gain of 0.92 in Motor Activity Log-Quality of Movement for the 60-hour group compared to the 0-hour group. There was no dose response for the Wolf Motor Function Test. Conclusions- For mild-to-moderately impaired stroke survivors, the dosage of patient-centered, task-specific practice systematically influences the gain in quality of arm use but not functional capacity. We caution that we may have been underpowered for the functional capacity outcome. These findings highlight the importance of recovery outcomes that capture arm use in the natural environment. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT01749358.