Efficacy of rehabilitative experience declines with time after focal ischemic brain injury

Low-Dose LPS Modulates Microglia/Macrophages Phenotypic Transformation to Amplify Rehabilitation Effects in Chronic Spinal Cord Injured (CSCI) Mice

Spinal cord injury (SCI) results in stalled motor function recovery under the chronic phase. One of the reasons due to the presence of ongoing inflammation. Therefore, regulating the status of immune cells may help reopen the window for neural repair, which represents a potential therapeutic target. In this study, we aimed to investigate whether this could be achieved in mice with cervical 5 crush CSCI (4 W) by utilizing a concentration of 0.5 mg/kg of lipopolysaccharide (LPS) to stimulate microglia/macrophages. Additionally, the mice underwent rehabilitation training for another 6 weeks. Our results showed that systemic injection of LPS enhanced the effects of forelimb rehabilitation training, as evaluated through single pellet grasping (SPG). Electrophysiological studies revealed the restoration of cortical drive to the injured side's forelimb muscles in the training combined with LPS group. Tract tracing studies demonstrated the reconstruction of cortical innervation to the cervical spinal cord. Furthermore, the levels of pro-inflammatory phenotype markers, such as inducible nitric oxide synthase (INOS) and CD68, decreased, while the expression of anti-inflammatory phenotype markers, including arginase 1 (ARG-1) and CD206, increased. Importantly, this phenotypic switch in microglia/macrophages was accompanied by an increase in phagocytic activity markers as indicated by BODIPY + IBA1 + staining. Collectively, our data suggests that low-dose LPS improves the effects of rehabilitation training by regulating the phenotypic transformation of microglia/macrophages in CSCI. This study provides a fresh perspective and intervention direction for the clinical treatment of chronic spinal cord injuries.

Advanced rehabilitation in ischaemic stroke research

At present, due to the rapid progress of treatment technology in the acute phase of ischaemic stroke, the mortality of patients has been greatly reduced but the number of disabled survivors is increasing, and most of them are elderly patients. Physicians and rehabilitation therapists pay attention to develop all kinds of therapist techniques including physical therapy techniques, robot-assisted technology and artificial intelligence technology, and study the molecular, cellular or synergistic mechanisms of rehabilitation therapies to promote the effect of rehabilitation therapy. Here, we discussed different animal and in vitro models of ischaemic stroke for rehabilitation studies; the compound concept and technology of neurological rehabilitation; all kinds of biological mechanisms of physical therapy; the significance, assessment and efficacy of neurological rehabilitation; the application of brain-computer interface, rehabilitation robotic and non-invasive brain stimulation technology in stroke rehabilitation.

Neuroimaging of motor recovery after ischemic stroke - functional reorganization of motor network

The long-term motor outcome of acute stroke patients may be correlated to the reorganization of brain motor network. Abundant neuroimaging studies contribute to understand the pathological changes and recovery of motor networks after stroke. In this review, we summarized how current neuroimaging studies have increased understanding of reorganization and plasticity in post stroke motor recovery. Firstly, we discussed the changes in the motor network over time during the motor-activation and resting states, as well as the overall functional integration trend of the motor network. These studies indicate that the motor network undergoes dynamic bilateral hemispheric functional reorganization, as well as a trend towards network randomization. In the second part, we summarized the current study progress in the application of neuroimaging technology to early predict the post-stroke motor outcome. In the third part, we discuss the neuroimaging techniques commonly used in the post-stroke recovery. These methods provide direct or indirect visualization patterns to understand the neural mechanisms of post-stroke motor recovery, opening up new avenues for studying spontaneous and treatment-induced recovery and plasticity after stroke.

Virtual Reality Action Observation and Motor Imagery to Enhance Neuroplastic Capacity in the Human Motor Cortex: A Pilot Double-blind, Randomized Cross-over Trial

Neuroplasticity is important for learning, development and recovery from injury. Therapies that can upregulate neuroplasticity are therefore of interest across a range of fields. We developed a novel virtual reality action observation and motor imagery (VR-AOMI) intervention and evaluated whether it could enhance the efficacy of mechanisms of neuroplasticity in the human motor cortex of healthy adults. A secondary question was to explore predictors of the change in neuroplasticity following VR-AOMI. A pre-registered, pilot randomized controlled cross-over trial was performed. Twenty right-handed adults (13 females; mean age: 23.0 ± 4.53 years) completed two experimental conditions in separate sessions; VR-AOMI and control. We used intermittent theta burst stimulation (iTBS) to induce long term potentiation-like plasticity in the motor cortex and recorded motor evoked potentials at multiple timepoints as a measure of corticospinal excitability. The VR-AOMI task did not significantly increase the change in MEP amplitude following iTBS when compared to the control task (Group × Timepoint interaction p = 0.17). However, regression analysis identified the change in iTBS response following VR-AOMI was significantly predicted by the baseline iTBS response in the control task. Specifically, participants that did not exhibit the expected increase in MEP amplitude following iTBS in the control condition appear to have greater excitability following iTBS in the VR-AOMI condition (r = -0.72, p < 0.001). Engaging in VR-AOMI might enhance capacity for neuroplasticity in some people who typically do not respond to iTBS. VR-AOMI may prime the brain for enhanced neuroplasticity in this sub-group.

Post Stroke Exercise Training: Intensity, Dosage, and Timing of Therapy

More intense, earlier exercise in rehabilitation results in improved motor outcomes following stroke. Timing and intensity of therapy delivery vary from study to study. For more intensive therapies, there are practical challenges in implementation. However, there are also opportunities for high intensity treatment through innovative approaches and new technologies. Timing of rehabilitation is important. As time post stroke increases, the dosage of therapy required to improve motor recovery outcomes increases. Very early rehabilitation may improve motor outcomes but should be delayed for at least 24 hours post stroke.

Aberrant cortical activity, functional connectivity, and neural assembly architecture after photothrombotic stroke in mice

Despite substantial progress in mapping the trajectory of network plasticity resulting from focal ischemic stroke, the extent and nature of changes in neuronal excitability and activity within the peri-infarct cortex of mice remains poorly defined. Most of the available data have been acquired from anesthetized animals, acute tissue slices, or infer changes in excitability from immunoassays on extracted tissue, and thus may not reflect cortical activity dynamics in the intact cortex of an awake animal. Here, in vivo two-photon calcium imaging in awake, behaving mice was used to longitudinally track cortical activity, network functional connectivity, and neural assembly architecture for 2 months following photothrombotic stroke targeting the forelimb somatosensory cortex. Sensorimotor recovery was tracked over the weeks following stroke, allowing us to relate network changes to behavior. Our data revealed spatially restricted but long-lasting alterations in somatosensory neural network function and connectivity. Specifically, we demonstrate significant and long-lasting disruptions in neural assembly architecture concurrent with a deficit in functional connectivity between individual neurons. Reductions in neuronal spiking in peri-infarct cortex were transient but predictive of impairment in skilled locomotion measured in the tapered beam task. Notably, altered neural networks were highly localized, with assembly architecture and neural connectivity relatively unaltered a short distance from the peri-infarct cortex, even in regions within 'remapped' forelimb functional representations identified using mesoscale imaging with anaesthetized preparations 8 weeks after stroke. Thus, using longitudinal two-photon microscopy in awake animals, these data show a complex spatiotemporal relationship between peri-infarct neuronal network function and behavioral recovery. Moreover, the data highlight an apparent disconnect between dramatic functional remapping identified using strong sensory stimulation in anaesthetized mice compared to more subtle and spatially restricted changes in individual neuron and local network function in awake mice during stroke recovery.

Micro-ultrasound based characterization of cerebrovasculature following focal ischemic stroke and upon short-term rehabilitation

Notwithstanding recanalization treatments in the acute stage of stroke, many survivors suffer long-term impairments. Physical rehabilitation is the only widely available strategy for chronic-stage recovery, but its optimization is hindered by limited understanding of its effects on brain structure and function. Using micro-ultrasound, behavioral testing, and electrophysiology, we investigated the impact of skilled reaching rehabilitation on cerebral hemodynamics, motor function, and neuronal activity in a rat model of focal ischemic stroke. A 50 MHz micro-ultrasound transducer and intracortical electrophysiology were utilized to characterize neurovascular changes three weeks following focal ischemia elicited by endothelin-1 injection into the sensorimotor cortex. Sprague-Dawley rats were rehabilitated through tray reaching, and their fine skilled reaching was assessed via the Montoya staircase. Focal ischemia led to a sustained deficit in forelimb reaching; and increased tortuosity of the penetrating vessels in the perilesional cortex; with no lateralization of spontaneous neuronal activity. Rehabilitation improved skilled reaching; decreased cortical vascularity; was associated with elevated peri- vs. contralesional hypercapnia-induced flow homogenization and increased perilesional spontaneous cortical neuronal activity. Our study demonstrated neurovascular plasticity accompanying rehabilitation-elicited functional recovery in the subacute stage following stroke, and multiple micro-ultrasound-based markers of cerebrovascular structure and function modified in recovery from ischemia and upon rehabilitation.

Dual-tDCS combined with sensorimotor training promotes upper limb function in subacute stroke patients: A randomized, double-blinded, sham-controlled study

BACKGROUND

Dual transcranial direct current stimulation (tDCS) over the bilateral primary somatosensory cortex (PSC) has potential benefits in stroke. In addition, compared with traditional rehabilitation training, sensorimotor training can significantly improve the sensorimotor function of patients. However, the efficacy of dual-tDCS combined with sensorimotor training in patients with subacute stroke is unknown.

OBJECTIVE

To assess whether dual-tDCS may enhance the efficacy of sensorimotor training on the upper limb functions in patients with subacute stroke. In addition, this study aims to explore the potential clinical mechanism of this combination therapy.

METHODS

We randomized 52 individuals with first-ever, unilateral subcortical stroke into the experimental group (n = 26) and the control group (n = 26). Patients in the experimental group received 20 min of dual-tDCS over the PSC and 40 min of sensorimotor training each session, while patients in the control group received sham dual-tDCS. The treatment cycle was a 1-h session of therapy each day, 5 days per week for 4 weeks. The Fugl-Meyer Assessment of Upper Extremity (FMA-UE) subscale, Action Research Arm Test (ARAT), Box and Block test (BBT), Erasmus MC revised Nottingham sensory assessment scale (Em-NSA), Neurometer sensory nerve quantitative detector (CPT), the Barthel index (BI), and Hospital Anxiety and Depression Scale (HADS) were used to assess upper limb function, activities of daily living (ADL), and mental health before and after the 4-week treatment period. In addition, functional near-infrared spectroscopy (fNIRS) was used to explore potential clinical brain mechanisms.

RESULTS

Both groups showed significant improvement in all clinical scales (All p < 0.05) after treatment. Compared with sham-tDCS plus sensorimotor training, active dual-tDCS coupled with sensorimotor training can significantly improve the FMA-UE, ARAT, Em-NSA-Stereognosis, and CPT-2K Hz. In addition, dual-tDCS combined with sensorimotor training can significantly activate the left pre-Motor and supplementary motor cortex (PM-SMC) and enhance the functional connection between the left somatosensory association cortex (SAC) and RPM-SMC. Furthermore, the difference of FMA-UE in the experimental group was positively correlated with the functional connectivity of RPM-SMC-LSAC (r = 0.815, p < 0.001).

CONCLUSION

Dual-tDCS over the PSC combined with sensorimotor training can improve upper limb sensory and motor dysfunction, enhance ADL, and alleviate depression and anxiety for subacute stroke patients. Our results indicated that RPM-SMC-LSAC may be potential therapeutic targets for dual-tDCS in upper limb rehabilitation on stroke.

Mesenchymal stem cells and their extracellular vesicles as emerging therapeutic tools in the treatment of ischemic stroke

Ischemic stroke (IS) is a neurological condition characterized by severe long-term consequences and an unfavorable prognosis for numerous patients. Despite advancements in stroke treatment, existing therapeutic approaches possess certain limitations. However, accumulating evidence suggests that mesenchymal stem/stromal cells (MSCs) hold promise as a potential therapy for various neurological disorders, including IS, owing to their advantageous properties, such as immunomodulation and tissue regeneration. Additionally, MSCs primarily exert their therapeutic effects through the release of extracellular vesicles (EVs), highlighting the significance of their paracrine activities. These EVs are small double-layered phospholipid membrane vesicles, carrying a diverse cargo of proteins, lipids, and miRNAs that enable effective cell-to-cell communication. Notably, EVs have emerged as attractive substitutes for stem cell therapy due to their reduced immunogenicity, lower tumorigenic potential, and ease of administration and handling. Hence, this review summarizes the current preclinical and clinical studies performed to investigate the safety and therapeutic potential of MSCs and their EVs derived from different sources, including bone marrow, adipose tissue, umbilical cord blood, and Wharton's jelly in IS.

Environmental Enrichment in Stroke Research: an Update

Environmental enrichment (EE) refers to different forms of stimulation, where the environment is designed to improve the levels of sensory, cognitive, and motor stimuli, inducing stroke recovery in animal models. Stroke is a leading cause of mortality and neurological disability among older adults, hence the importance of developing strategies to improve recovery for such patients. This review provides an update on recent findings, compiling information regarding the parameters affected by EE exposure in both preclinical and clinical studies. During stroke recovery, EE exposure has been shown to improve both the cognitive and locomotor aspects, inducing important neuroplastic alterations, increased angiogenesis and neurogenesis, and modified gene expression, among other effects. There is a need for further research in this field, particularly in those aspects where the evidence is inconclusive. Moreover, it is necessary refine and adapt the EE paradigms for application in human patients.

Alternate Day Fasting Leads to Improved Post-Stroke Motor Recovery in Mice

BACKGROUND

Caloric restriction promotes neuroplasticity and recovery after neurological injury. In mice, we tested the hypothesis that caloric restriction can act post-stroke to enhance training-associated motor recovery.

METHODS

Mice were trained to perform a skilled prehension task. We then induced a photothrombotic stroke in the caudal forelimb area, after which we retrained animals on the prehension task following an 8-day delay. Mice underwent either ad libitum feeding or alternate day fasting beginning 1-day after stroke and persisting for either 7 days or the entire post-stroke training period until sacrifice.

RESULTS

Prior studies have shown that post-stroke recovery of prehension can occur if animals receive rehabilitative training during an early sensitive period but is incomplete if rehabilitative training is delayed. In contrast, we show complete recovery of prehension, despite a delay in rehabilitative training, when mice underwent alternate day fasting beginning 1-day post-stroke and persisting for either 7 days or the entire post-stroke training period until sacrifice. Recovery was independent of weight loss. Stroke volumes were similar across groups.

CONCLUSIONS

Post-stroke caloric restriction led to recovery of motor function independent of a protective effect on stroke volume. Prehension recovery improved even after ad libitum feeding was reinstituted suggesting that the observed motor recovery was not merely a motivational response. These data add to the growing evidence that post-stroke caloric restriction can enhance recovery.

Measuring Neuroplasticity in Response to Cardiovascular Exercise in People With Stroke: A Critical Perspective

BACKGROUND

Rehabilitative treatments that promote neuroplasticity are believed to improve recovery after stroke. Animal studies have shown that cardiovascular exercise (CE) promotes neuroplasticity but the effects of this intervention on the human brain and its implications for the functional recovery of patients remain unclear. The use of biomarkers has enabled the assessment of cellular and molecular events that occur in the central nervous system after brain injury. Some of these biomarkers have proven to be particularly valuable for the diagnosis of severity, prognosis of recovery, as well as for measuring the neuroplastic response to different treatments after stroke.

OBJECTIVES

To provide a critical analysis on the current evidence supporting the use of neurophysiological, neuroimaging, and blood biomarkers to assess the neuroplastic response to CE in individuals poststroke.

RESULTS

Most biomarkers used are responsive to the effects of acute and chronic CE interventions, but the response appears to be variable and is not consistently associated with functional improvements. Small sample sizes, methodological variability, incomplete information regarding patient's characteristics, inadequate standardization of training parameters, and lack of reporting of associations with functional outcomes preclude the quantification of the neuroplastic effects of CE poststroke using biomarkers.

CONCLUSION

Consensus on the optimal biomarkers to monitor the neuroplastic response to CE is currently lacking. By addressing critical methodological issues, future studies could advance our understanding of the use of biomarkers to measure the impact of CE on neuroplasticity and functional recovery in patients with stroke.

Effects of virtual reality in the early-stage stroke rehabilitation: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Virtual reality (VR) is an emerging technology and has shown promising outcomes in stroke rehabilitation. VR can create an enriched environment, facilitate task-specific training, and provide multimodal sensorimotor feedback to augment functional recovery by driving the experience-dependent plasticity, which is prominent in the early-stage after stroke.

PURPOSE

This review aimed to systematically identify and examine the feasibility and effectiveness of VR intervention applied within one-month after stroke on functional outcomes of patients.

METHODS

Randomized controlled trials were searched across six databases published between 2000 and 2021. Two independent reviewers conducted study selection, data extraction, and quality assessment. Physiotherapy Evidence Database (PEDro) scale was used to evaluate the quality of included studies. Qualitative synthesis and meta-analysis were conducted to compare VR-based rehabilitation and conventional rehabilitation.

RESULTS

Seventeen randomized controlled trials were included in this review, and all of them meet the criteria for good quality. The results confirmed the feasibility of applying VR in early stroke rehabilitation. In the meta-analyses, there were no significant differences between VR and control on upper extremity function (SMD = 0.22, P = .10), Activities of Daily Living outcomes (SMD = 0.15, P = .11), balance (SMD = 0.18, P = .86), and cognition (SMD = 0.34, P = .06).

CONCLUSION

VR is a feasible approach and demonstrates comparable effectiveness in functional outcomes with conventional rehabilitation in patients with stroke at the early-stage. Further research focusing on the application of VR in acute stroke survivors with adequate sample size, additional follow-up evaluation and valid outcome measures are warranted.

Ginkgolide B promotes spontaneous recovery and enhances endogenous netrin-1 after neonatal hypoxic-ischemic brain damage

OBJECTIVES

Perinatal hypoxic-ischemic encephalopathy (HIE) is a condition that can lead to long-term cognitive, motor, and behavioral impairments in newborns. Although brain hypothermia therapy is currently the standard treatment for HIE, it does not provide complete neuroprotection. As a result, there is a need to explore additional therapies to enhance treatment outcomes. This study aims to investigate the potential role of Ginkgolide B (GB) in promoting neuroplasticity and facilitating spontaneous recovery after HIE.

METHODS

In this study, we employed a neonatal rat model of HIE to investigate the effects of GB on spontaneous recovery. GB treatment was initiated 24 h after hypoxia and administered continuously for a duration of 14 days. We evaluated several outcome measures after the treatment period, including spontaneous behavioral recovery and brain repair. Additionally, we quantified the levels of netrin-1 in both plasma and the peri-ischemic zone after the occurrence of HIE.

RESULTS

We found that GB treatment significantly facilitated spontaneous behavioral recovery in the HIE pups. Furthermore, cognitive function was restored, and brain tissue repair had a noticeable acceleration. We observed increased cell proliferation in the subventricular, stratum, and subgranular zones. Of particular interest, we observed elevated levels of netrin-1 in both plasma and the ischemic penumbra following GB treatment.

CONCLUSION

Our findings suggest that GB promotes neuroplasticity and enhances spontaneous recovery in newborns affected by HIE. The observed upregulation of netrin-1 may be crucial in mediating these effects. These results highlight the promising potential of GB as a post-HIE therapy, particularly in enhancing spontaneous recovery and improving long-term outcomes.

Expansion of plasma MicroRNAs over the first month following human stroke

Few have characterized miRNA expression during the transition from injury to neural repair and secondary neurodegeneration following stroke in humans. We compared expression of 754 miRNAs from plasma samples collected 5, 15, and 30 days post-ischemic stroke from a discovery cohort (n = 55) and 15-days post-ischemic stroke from a validation cohort (n = 48) to healthy control samples (n = 55 and 48 respectively) matched for age, sex, race and cardiovascular comorbidities using qRT-PCR. Eight miRNAs remained significantly altered across all time points in both cohorts including many described in acute stroke. The number of significantly dysregulated miRNAs more than doubled from post-stroke day 5 (19 miRNAs) to days 15 (50 miRNAs) and 30 (57 miRNAs). Twelve brain-enriched miRNAs were significantly altered at one or more time points (decreased expression, stroke versus controls: miR-107; increased expression: miR-99-5p, miR-127-3p, miR-128-3p, miR-181a-3p, miR-181a-5p, miR-382-5p, miR-433-3p, miR-491-5p, miR-495-3p, miR-874-3p, and miR-941). Many brain-enriched miRNAs were associated with apoptosis over the first month post-stroke whereas other miRNAs suggested a transition to synapse regulation and neuronal protection by day 30. These findings suggest that a program of decreased cellular proliferation may last at least 30 days post-stroke, and points to specific miRNAs that could contribute to neural repair in humans.

Post-Stroke Brain Health Monitoring and Optimization: A Narrative Review

Significant advancements have been made in recent years in the acute treatment and secondary prevention of stroke. However, a large proportion of stroke survivors will go on to have enduring physical, cognitive, and psychological disabilities from suboptimal post-stroke brain health. Impaired brain health following stroke thus warrants increased attention from clinicians and researchers alike. In this narrative review based on an open timeframe search of the PubMed, Scopus, and Web of Science databases, we define post-stroke brain health and appraise the body of research focused on modifiable vascular, lifestyle, and psychosocial factors for optimizing post-stroke brain health. In addition, we make clinical recommendations for the monitoring and management of post-stroke brain health at major post-stroke transition points centered on four key intertwined domains: cognition, psychosocial health, physical functioning, and global vascular health. Finally, we discuss potential future work in the field of post-stroke brain health, including the use of remote monitoring and interventions, neuromodulation, multi-morbidity interventions, enriched environments, and the need to address inequities in post-stroke brain health. As post-stroke brain health is a relatively new, rapidly evolving, and broad clinical and research field, this narrative review aims to identify and summarize the evidence base to help clinicians and researchers tailor their own approach to integrating post-stroke brain health into their practices.

Motor Rehabilitation Provides Modest Functional Benefits After Intracerebral Hemorrhage: a Systematic Review and Meta-Analysis of Translational Rehabilitation Studies

Few certainties exist regarding the optimal type, timing, or dosage of rehabilitation after stroke. Despite differing injury mechanisms and recovery patterns following ischemic and hemorrhagic stroke, most translational stroke research is conducted after ischemia. As we enter the era of personalized medicine, exploring subtype-specific treatment efficacy is essential to optimizing recovery. Our objective was to characterize common rehabilitation interventions used after in vivo preclinical intracerebral hemorrhage (ICH) and assess the impact of post-ICH rehabilitation (vs. no-rehabilitation) on recovery of motor function. Following PRISMA guidelines, a systematic review (Academic Search Complete, CINAHL, EMBASE, Medline, PubMed Central) identified eligible articles published up to December 2022. Risk of bias (SYRCLE) and study quality (CAMARADES) were evaluated, and random-effects meta-analysis was used to assess treatment efficacy in recovery of forelimb and locomotor functions. Thirty articles met inclusion criteria, and 48 rehabilitation intervention groups were identified. Most used collagenase to model striatal ICH in young, male rodents. Aerobic exercise, enriched rehabilitation, and constraint-induced movement therapy represented ~ 70% of interventions. Study quality was low (median 4/10, range 2-8), and risk of bias was unclear. Rehabilitation provided modest benefits in skilled reaching, spontaneous impaired forelimb use, and locomotor function; however, effects varied substantially by endpoint, treatment type, and study quality. Rehabilitation statistically improves motor function after preclinical ICH, but whether these effects are functionally meaningful is unclear. Incomplete reporting and variable research quality hinder our capacity to analyze and interpret how treatment factors influence rehabilitation efficacy and recovery after ICH.

Feasibility and outcomes of supplemental gait training by robotic and conventional means in acute stroke rehabilitation

INTRODUCTION

Practicality of implementation and dosing of supplemental gait training in an acute stroke inpatient rehabilitation setting are not well studied but can have positive impact on outcomes.

OBJECTIVES

To determine the feasibility of early, intense supplemental gait training in inpatient stroke rehabilitation, compare functional outcomes and the specific mode of delivery.

DESIGN AND SETTING

Assessor blinded, randomized controlled trial in a tertiary Inpatient Rehabilitation Facility.

PARTICIPANTS

Thirty acute post-stroke patients with unilateral hemiparesis (≥ 18 years of age with a lower limb MAS ≤ 3).

INTERVENTION

Lokomat® or conventional gait training (CGT) in addition to standard mandated therapy time.

MAIN OUTCOME MEASURES

Number of therapy sessions; adverse events; functional independence measure (FIM motor); functional ambulation category (FAC); passive range of motion (PROM); modified Ashworth scale (MAS); 5 times sit-to-stand (5x-STS); 10-m walk test (10MWT); 2-min walk test (2MWT) were assessed before (pre) and after training (post).

RESULTS

The desired supplemental therapy was implemented during normal care delivery hours and the patients generally tolerated the sessions well. Both groups improved markedly on several measures; the CGT group obtained nearly 45% more supplemental sessions (12.8) than the Lokomat® group (8.9). Both groups showed greater FIM improvement scores (discharge - admission) than those from a reference group receiving no supplemental therapy. An overarching statistical comparison between methods was skewed towards a differential benefit (but not significant) in the Lokomat® group with medium effect sizes. By observation, the robotic group completed a greater number of steps, on average. These results provide some evidence for Lokomat® being a more efficient tool for gait retraining by providing a more optimal therapy "dose".

CONCLUSIONS

With careful planning, supplemental therapy was possible with minimal intrusion to schedules and was well tolerated. Participants showed meaningful functional improvement with relatively little supplemental therapy over a relatively short time in study.

Moderate intensity aerobic exercise may enhance neuroplasticity of the contralesional hemisphere after stroke: a randomised controlled study

Upregulation of neuroplasticity might help maximize stroke recovery. One intervention that appears worthy of investigation is aerobic exercise. This study aimed to determine whether a single bout of moderate intensity aerobic exercise can enhance neuroplasticity in people with stroke. Participants were randomly assigned (1:1) to a 20-min moderate intensity exercise intervention or remained sedentary (control). Transcranial magnetic stimulation measured corticospinal excitability of the contralesional hemisphere by recording motor evoked potentials (MEPs). Intermittent Theta Burst Stimulation (iTBS) was used to repetitively activate synapses in the contralesional primary motor cortex, initiating the early stages of neuroplasticity and increasing excitability. It was surmised that if exercise increased neuroplasticity, there would be a greater facilitation of MEPs following iTBS. Thirty-three people with stroke participated in this study (aged 63.87 ± 10.30 years, 20 male, 6.13 ± 4.33 years since stroke). There was an interaction between Time*Group on MEP amplitudes (P = 0.009). Participants allocated to aerobic exercise had a stronger increase in MEP amplitude following iTBS. A non-significant trend indicated time since stroke might moderate this interaction (P = 0.055). Exploratory analysis suggested participants who were 2-7.5 years post stroke had a strong MEP facilitation following iTBS (P < 0.001). There was no effect of age, sex, resting motor threshold, self-reported physical activity levels, lesion volume or weighted lesion load (all P > 0.208). Moderate intensity cycling may enhance neuroplasticity in people with stroke. This therapy adjuvant could provide opportunities to maximize stroke recovery.

Cerebellar deep brain stimulation for chronic post-stroke motor rehabilitation: a phase I trial

Upper-extremity impairment after stroke remains a major therapeutic challenge and a target of neuromodulation treatment efforts. In this open-label, non-randomized phase I trial, we applied deep brain stimulation to the cerebellar dentate nucleus combined with renewed physical rehabilitation to promote functional reorganization of ipsilesional cortex in 12 individuals with persistent (1-3 years), moderate-to-severe upper-extremity impairment. No serious perioperative or stimulation-related adverse events were encountered, with participants demonstrating a seven-point median improvement on the Upper-Extremity Fugl-Meyer Assessment. All individuals who enrolled with partial preservation of distal motor function exceeded minimal clinically important difference regardless of time since stroke, with a median improvement of 15 Upper-Extremity Fugl-Meyer Assessment points. These robust functional gains were directly correlated with cortical reorganization evidenced by increased ipsilesional metabolism. Our findings support the safety and feasibility of deep brain stimulation to the cerebellar dentate nucleus as a promising tool for modulation of late-stage neuroplasticity for functional recovery and the need for larger clinical trials. ClinicalTrials.gov registration: NCT02835443 .

Electric Field Navigated 1-Hz rTMS for Poststroke Motor Recovery: The E-FIT Randomized Controlled Trial

BACKGROUND

To determine if low-frequency repetitive transcranial magnetic stimulation targeting the primary motor cortex contralateral (M1CL) to the affected corticospinal tract in patients with hemiparetic stroke augments intensive training-related clinical improvement; an extension of the NICHE trial (Navigated Inhibitory rTMS to Contralesional Hemisphere Trial) using an alternative sham coil.

METHODS

The present E-FIT trial (Electric Field Navigated 1Hz rTMS for Post-stroke Motor Recovery Trial) included 5 of 12 NICHE trial outpatient US rehabilitation centers. The stimulation protocol remained identical (1 Hz repetitive transcranial magnetic stimulation, M1CL, preceding 60-minute therapy, 18 sessions/6 wks; parallel arm randomized clinical trial). The sham coil appearance mimicked the active coil but without the weak electric field in the NICHE trial sham coil. Outcomes measured 1 week, and 1, 3, and 6 months after the end of treatment included the following: upper extremity Fugl-Meyer (primary, 6 months after end of treatment), Action Research Arm Test, National Institutes of Health Stroke Scale, quality of life (EQ-5D), and safety.

RESULTS

Of 60 participants randomized, 58 completed treatment and were included for analysis. Bayesian analysis of combined data from the E-FIT and the NICHE trials indicated that active treatment was not superior to sham at the primary end point (posterior mean odds ratio of 1.94 [96% credible interval of 0.61-4.80]). For the E-FIT intent-to-treat population, upper extremity Fugl-Meyer improvement ≥5 pts occurred in 60% (18/30) active group and 50% (14/28) sham group. Participants enrolled 3 to 6 months following stroke had a 67% (31%-91% CI) response rate in the active group at the 6-month end point versus 50% in the sham group (21.5%-78.5% CI). There were significant improvements from baseline to 6 months for both active and sham groups in upper extremity Fugl-Meyer, Action Research Arm Test, and EQ-5D (P<0.05). Improvement in National Institutes of Health Stroke Scale was observed only in the active group (P=0.004). Ten serious unrelated adverse events occurred (4 active group, 6 sham group, P=0.72).

CONCLUSIONS

Intensive motor rehabilitation 3 to 12 months after stroke improved clinical impairment, function, and quality of life; however, 1 Hz-repetitive transcranial magnetic stimulation was not an effective treatment adjuvant in the present sample population with mixed lesion location and extent.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03010462.

Post-ischemic reorganization of sensory responses in cerebral cortex

Introduction

Sensorimotor integration is critical for generating skilled, volitional movements. While stroke tends to impact motor function, there are also often associated sensory deficits that contribute to overall behavioral deficits. Because many of the cortico-cortical projections participating in the generation of volitional movement either target or pass-through primary motor cortex (in rats, caudal forelimb area; CFA), any damage to CFA can lead to a subsequent disruption in information flow. As a result, the loss of sensory feedback is thought to contribute to motor dysfunction even when sensory areas are spared from injury. Previous research has suggested that the restoration of sensorimotor integration through reorganization or de novo neuronal connections is important for restoring function. Our goal was to determine if there was crosstalk between sensorimotor cortical areas with recovery from a primary motor cortex injury. First, we investigated if peripheral sensory stimulation would evoke responses in the rostral forelimb area (RFA), a rodent homologue to premotor cortex. We then sought to identify whether intracortical microstimulation-evoked activity in RFA would reciprocally modify the sensory response.

Methods

We used seven rats with an ischemic lesion of CFA. Four weeks after injury, the rats' forepaw was mechanically stimulated under anesthesia and neural activity was recorded in the cortex. In a subset of trials, a small intracortical stimulation pulse was delivered in RFA either individually or paired with peripheral sensory stimulation.

Results

Our results point to post-ischemic connectivity between premotor and sensory cortex that may be related to functional recovery. Premotor recruitment during the sensory response was seen with a peak in spiking within RFA after the peripheral solenoid stimulation despite the damage to CFA. Furthermore, stimulation in RFA modulated and disrupted the sensory response in sensory cortex.

Discussion

The presence of a sensory response in RFA and the sensitivity of S1 to modulation by intracortical stimulation provides additional evidence for functional connectivity between premotor and somatosensory cortex. The strength of the modulatory effect may be related to the extent of the injury and the subsequent reshaping of cortical connections in response to network disruption.

Broad Therapeutic Time Window for Driving Motor Recovery After TBI Using Activity-Dependent Stimulation

BACKGROUND

After an acquired injury to the motor cortex, the ability to generate skilled movements is impaired, leading to long-term motor impairment and disability. While rehabilitative therapy can improve outcomes in some individuals, there are no treatments currently available that are able to fully restore lost function.

OBJECTIVE

We previously used activity-dependent stimulation (ADS), initiated immediately after an injury, to drive motor recovery. The objective of this study was to determine if delayed application of ADS would still lead to recovery and if the recovery would persist after treatment was stopped.

METHODS

Rats received a controlled cortical impact over primary motor cortex, microelectrode arrays were implanted in ipsilesional premotor and somatosensory areas, and a custom brain-machine interface was attached to perform the ADS. Stimulation was initiated either 1, 2, or 3 weeks after injury and delivered constantly over a 4-week period. An additional group was monitored for 8 weeks after terminating ADS to assess persistence of effect. Results were compared to rats receiving no stimulation.

RESULTS

ADS was delayed up to 3 weeks from injury onset and still resulted in significant motor recovery, with maximal recovery occurring in the 1-week delay group. The improvements in motor performance persisted for at least 8 weeks following the end of treatment.

CONCLUSIONS

ADS is an effective method to treat motor impairments following acquired brain injury in rats. This study demonstrates the clinical relevance of this technique as it could be initiated in the post-acute period and could be explanted/ceased once recovery has occurred.

High-intensity training with short and long intervals regulate cortical neurotrophic factors, apoptosis markers and chloride homeostasis in rats with stroke

BACKGROUND/PURPOSE

The optimal endurance exercise parameters remain to be defined to potentiate long-term functional recovery after stroke. We aim to assess the effects of individualized high-intensity interval training (HIIT) with either long or short intervals on neurotrophic factors and their receptors, apoptosis markers and the two-main cation-chloride cotransporters in the ipsi- and contralesional cerebral cortices in rats with cerebral ischemia. Endurance performance and sensorimotor functions were also assessed METHODS: : Rats with a 2-hour transient middle cerebral artery occlusion (tMCAO) performed work-matched HIIT4 (intervals: 4min) or HIIT1 (intervals: 1min) on treadmill for 2 weeks. Incremental exercises and sensorimotor tests were performed at day 1 (D1), D8, and D15 after tMCAO. Molecular analyses were achieved in both the paretic and non-paretic triceps brachii muscles and the ipsi- and contralesional cortices at D17 RESULTS: : Gains in endurance performance are in a time-dependent manner from the first week of training. This enhancement is supported by the upregulation of metabolic markers in both triceps brachii muscles. Both regimens alter the expression of neurotrophic markers and chloride homeostasis in a specific manner in the ipsi- and contralesional cortices. HIIT acts on apoptosis markers by promoting anti-apoptotic proteins in the ipsilesional cortex CONCLUSION: : HIIT regimens seem to be of clinical relevance in the critical period of stroke rehabilitation by strongly improving aerobic performance. Also, the observed cortical changes suggest an influence of HIIT on neuroplasticity in both ipsi- and contralesional hemispheres. Such neurotrophic markers might be considered as biomarkers of functional recovery in individuals with stroke.

Can specific virtual reality combined with conventional rehabilitation improve poststroke hand motor function? A randomized clinical trial

TRIAL OBJECTIVE

To verify whether conventional rehabilitation combined with specific virtual reality is more effective than conventional therapy alone in restoring hand motor function and muscle tone after stroke.

TRIAL DESIGN

This prospective single-blind randomized controlled trial compared conventional rehabilitation based on physiotherapy and occupational therapy (control group) with the combination of conventional rehabilitation and specific virtual reality technology (experimental group). Participants were allocated to these groups in a ratio of 1:1. The conventional rehabilitation therapists were blinded to the study, but neither the participants nor the therapist who applied the virtual reality-based therapy could be blinded to the intervention.

PARTICIPANTS

Forty-six patients (43 of whom completed the intervention period and follow-up evaluation) were recruited from the Neurology and Rehabilitation units of the Hospital General Universitario of Talavera de la Reina, Spain.

INTERVENTION

Each participant completed 15 treatment sessions lasting 150 min/session; the sessions took place five consecutive days/week over the course of three weeks. The experimental group received conventional upper-limb strength and motor training (100 min/session) combined with specific virtual reality technology devices (50 min/session); the control group received only conventional training (150 min/session).

RESULTS

As measured by the Ashworth Scale, a decrease in wrist muscle tone was observed in both groups (control and experimental), with a notably larger decrease in the experimental group (baseline mean/postintervention mean: 1.22/0.39; difference between baseline and follow-up: 0.78; 95% confidence interval: 0.38-1.18; effect size = 0.206). Fugl-Meyer Assessment scores were observed to increase in both groups, with a notably larger increase in the experimental group (total motor function: effect size = 0.300; mean: - 35.5; 95% confidence interval: - 38.9 to - 32.0; wrist: effect size = 0.290; mean: - 5.6; 95% confidence interval: - 6.4 to - 4.8; hand: effect size = 0.299; mean: - -8.9; 95% confidence interval: - 10.1 to - 7.6). On the Action Research Arm Test, the experimental group quadrupled its score after the combined intervention (effect size = 0.321; mean: - 32.8; 95% confidence interval: - 40.1 to - 25.5).

CONCLUSION

The outcomes of the study suggest that conventional rehabilitation combined with a specific virtual reality technology system can be more effective than conventional programs alone in improving hand motor function and voluntary movement and in normalizing muscle tone in subacute stroke patients. With combined treatment, hand and wrist functionality and motion increase; resistance to movement (spasticity) decreases and remains at a reduced level.

TRIALS REGISTRY

International Clinical Trials Registry Platform: ISRCTN27760662 (15/06/2020; retrospectively registered).

Effects of Virtual Reality-Based Exercise on Balance in Patients With Stroke: A Systematic Review and Meta-analysis

OBJECTIVE

The aim of the study is to quantify the effects of virtual reality-based exercise on balance after stroke.

DESIGN

The PubMed, Embase, Cochrane Library, Cumulative Index of Nursing and Allied Health Literature, and Web of Science databases were searched until December 31, 2021. Independent investigators abstracted data, assessed the quality of the evidence, and rated the certainty of the evidence. The intergroup differences were determined by calculating mean difference and 95% confidence interval by RevMan 5.3 software.

RESULTS

Fourteen randomized controlled trials involving 423 stroke patients were included. Patients who received virtual reality-based exercise illustrated marked improvements in the Berg Balance Scale (mean difference, 1.35; 95% confidence interval, 0.58 to 1.86; P < 0.00001; I2 = 44%), Timed Up and Go test (mean difference, -0.81; 95% confidence interval, -1.18 to -0.44; P < 0.0001; I2 = 0%), Functional Reach Test (mean difference, 3.06; 95% confidence interval, 1.31-4.80; P = 0.0006; I2 = 0%), 10-Meters Walking Test (mean difference, -1.53; 95% confidence interval, -2.92 to -0.13; P = 0.03; I2 = 33%), and Modified Barthel Index (mean difference, 5.26; 95% confidence interval, 1.70 to 8.82; P = 0.004; I2 = 0%) compared with the control group.

CONCLUSIONS

Existing low-evidence analyses showed that virtual reality-based exercise could effectively and safely improve balance in chronic stroke. Longer-term virtual reality-based exercise was more effective on functional ability of stroke.

A checklist-based survey for early mobilization of stroke unit patients in an Italian region

BACKGROUND

Although early mobilization (EM) is recommended by most guidelines in acute stroke patients, there is a paucity of tools to perform a standardized patient risk assessment prior to EM in stroke units (SUs).

OBJECTIVE

This survey aimed at assessing (1) the usefulness of an ad hoc checklist for a standardized approach to EM in SUs and (2) the relationship between EM achieved by this checklist and SU characteristics.

METHODS

This survey was carried out in 10 SUs in Piedmont, Italy. The EM checklist was based on 15 "items", including quantitative/qualitative, clinical and management features.

RESULTS

A total of 250 completed checklists were assessed. EM, defined as out-of-bed activity within 72 h of admission, was reached by 174 patients (69.6%), according to the checklist. There was a statistically significant association between the admission NIHSS score and EM. Hypotension at mobilization was observed in 29/250 patients (11.6%) and was significantly associated with EM. A total of 6 falls (2.4%) were reported. Nurses were most frequently involved in EM, either alone (40.8%) or with another professional.

CONCLUSION

A large percentage of acute stroke patients managed to achieve a safe EM in the SUs that adopted the novel checklist. These results suggest that this checklist may well be a user-friendly, reliable tool to assist SU professionals in deciding whether to mobilize or not, by means of a standardized approach.

Nonpharmacological Treatments for Hospitalized Patients with Stroke: A Nuanced Approach to Prescribing Early Activity

Stroke remains a leading cause of adult disability. To date, hyperacute revascularization procedures reach 5-10% of stroke patients even in high resource health systems. There is a limited time window for brain repair after stroke, and therefore, the activities such as prescribed exercise in the earliest period will likely have long-term significant consequences. Clinicians who provide care for hospitalized stroke patients make treatment decisions specific to activity often without guidelines to direct these prescriptions. This requires a balanced understanding of the available evidence for early post-stroke exercise and physiological principles after stroke that drive the safety of prescribed exercise. Here, we provide a summary of these relevant concepts, identify gaps, and recommend an approach to prescribing safe and meaningful activity for all patients with stroke. The population of thrombectomy-eligible stroke patients can be used as the exemplar for conceptualization.

Telerehabilitation Initiated Early in Post-Stroke Recovery: A Feasibility Study

BACKGROUND

Enhanced neural plasticity early after stroke suggests the potential to improve outcomes with intensive rehabilitation therapy. Most patients do not get such therapy, however, due to limited access, changing rehabilitation therapy settings, low therapy doses, and poor compliance.

OBJECTIVE

To examine the feasibility, safety, and potential efficacy of an established telerehabilitation (TR) program after stroke initiated during admission to an inpatient rehabilitation facility (IRF) and completed in the patient's home.

METHODS

Participants with hemiparetic stroke admitted to an IRF received daily TR targeting arm motor function in addition to usual care. Treatment consisted of 36, 70-minute sessions (half supervised by a licensed therapist via videoconference), over a 6-week period, that included functional games, exercise videos, education, and daily assessments.

RESULTS

Sixteen participants of 19 allocated completed the intervention (age 61.3 ± 9.4 years; 6 female; baseline Upper Extremity Fugl-Meyer [UEFM] score 35.9 ± 6.4 points, mean ± SD; NIHSS score 4 (3.75, 5.25), median, IQR; intervention commenced 28.3 ± 13.0 days post-stroke). Compliance was 100%, retention 84%, and patient satisfaction 93%; 2 patients developed COVID-19 and continued TR. Post-intervention UEFM improvement was 18.1 ± 10.9 points (P < .0001); Box and Blocks, 22.4 ± 9.8 blocks (P = .0001). Digital motor assessments, acquired daily in the home, were concordant with these gains. The dose of rehabilitation therapy received as usual care during this 6-week interval was 33.9 ± 20.3 hours; adding TR more than doubled this to 73.6 ± 21.8 hours (P < .0001). Patients enrolled in Philadelphia could be treated remotely by therapists in Los Angeles.

CONCLUSIONS

These results support feasibility, safety, and potential efficacy of providing intense TR therapy early after stroke.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov; NCT04657770.

Oral Treatment with the Extract of Euterpe oleracea Mart. Improves Motor Dysfunction and Reduces Brain Injury in Rats Subjected to Ischemic Stroke

Ischemic stroke is one of the principal causes of morbidity and mortality around the world. The pathophysiological mechanisms that lead to the formation of the stroke lesions range from the bioenergetic failure of the cells and the intense production of reactive oxygen species to neuroinflammation. The fruit of the açaí palm, Euterpe oleracea Mart. (EO), is consumed by traditional populations in the Brazilian Amazon region, and it is known to have antioxidant and anti-inflammatory properties. We evaluated whether the clarified extract of EO was capable of reducing the area of lesion and promoting neuronal survival following ischemic stroke in rats. Animals submitted to ischemic stroke and treated with EO extract presented a significant improvement in their neurological deficit from the ninth day onward. We also observed a reduction in the extent of the cerebral injury and the preservation of the neurons of the cortical layers. Taken together, our findings indicate that treatment with EO extract in the acute phase following a stroke can trigger signaling pathways that culminate in neuronal survival and promote the partial recovery of neurological scores. However, further detailed studies of the intracellular signaling pathways are needed to better understand the mechanisms involved.

Performing Enriched Environment Studies to Improve Functional Recovery

Physical therapy and social interactions between the stroke patient and healthcare professionals or relatives facilitate the process of recovery and promote improvement of lost neurological function after stroke. These observations can be mimicked in an experimental setting by multimodal stimulation provided in the concept of enriched environment. The enriched environment is a housing condition combining social interactions and sensorimotor stimulation that improves lost neurological function without affecting the extent of brain damage after experimental stroke. This chapter provides a detailed protocol on how to perform enriched housing experiments including conceptual and technical considerations as a tool to investigate mechanisms of recovery after brain injury.

Cost-effectiveness of seven-days-per-week rehabilitation schedule for acute stroke patients

BACKGROUND

Rehabilitation is an essential medical service for patients who have suffered acute stroke. Although the effectiveness of 7-days-per-week rehabilitation schedule has been studied in comparison with 5- or 6-days-per-week rehabilitation schedule, its cost-effectiveness has not been analyzed. In this research, to help formulate more cost-effective medical treatments for acute stroke patients, we analyzed the cost-effectiveness of 7-days-per-week rehabilitation for acute stroke from public health payer's perspective, and public healthcare and long-term care payer's perspective in Japan.

METHODS

Cost-effectiveness of 7-days-per-week rehabilitation for acute stroke patients was analyzed based on the result from a previous study using a Japanese database examining the efficacy of 7-days-per-week rehabilitation. Cost utility analysis was conducted by comparing 7-days-per-week rehabilitation with 5- or 6-days-per-week rehabilitation, with its main outcome incremental cost-effectiveness ratio (ICER) calculated by dividing estimated incremental medical and long-term care costs by incremental quality-adjusted life years (QALY). The costs were estimated using the Japanese fee table and from published sources. The time horizon was 5 years, and Markov modeling was used for the analysis.

RESULTS

The ICER was $6339/QALY from public health payer's perspective, lower than 5,000,000 Yen/QALY (approximately US$37,913), which was the willingness-to-pay used for the cost-effectiveness evaluation in Japan. The 7-day-per-week rehabilitation was dominant from public healthcare and long-term care payer's perspective. The result of sensitivity analysis confirmed the results.

CONCLUSION

The results indicated that 7-days-per-week rehabilitation for acute stroke rehabilitation was likely to be cost-effective.

Addressing the Operational Challenges for Outpatient Stroke Rehabilitation

ABSTRACT

The traditional model of rehabilitation services includes clear requirements for provision of services in the acute inpatient rehabilitation setting. However, there are fewer guidelines on the frequency and duration of rehabilitation services beyond the acute setting. Recent research has suggested that neurorehabilitation interventions that are provided frequently enough upon discharge from acute inpatient rehabilitation to facilitate repeated practice and feedback improve long-term stroke outcomes. However, it is challenging to provide high-frequency outpatient rehabilitation, as the logistics of scheduling and insurance limitations often do not allow it. The Sheikh Khalifa Stroke Institute at Johns Hopkins Medicine innovated a new model to provide the appropriate frequency of therapy for stroke rehabilitation in the outpatient setting. This article describes the restructured operational infrastructure for outpatient stroke rehabilitation to facilitate high-frequency transdisciplinary stroke rehabilitation in the real world, including the development of the outpatient postacute therapy programs and the identification of appropriate patients for each program, the development of scheduling matrices and treating teams to deliver the postacute therapy programs, the implementation of transdisciplinary neurorehabilitation, and the steps taken to empower patients to engage in rehabilitation at home and address barriers to accessing the programs. We assessed the effect of the operational restructuring on schedule utilization, no-show rates, and cancellation rates in the 3 mos before and after implementation of the program and show that it increased schedule utilization and reduced no-show rates and cancellation rates, suggesting that it may increase compliance with rehabilitation. It is possible to create the infrastructure needed to bridge the continuum of care for poststroke recovery and rehabilitation.

Bringing High-Dose Neurorestorative Behavioral Training Into the Acute Stroke Unit

ABSTRACT

Stroke remains common and is a leading cause of adult disability. While there have been enormous system changes for the diagnosis and delivery of hyperacute stroke treatments at comprehensive stroke centers, few advances have been made in those same centers for treatments focused on behavioral recovery and brain repair. Specifically, during the early hospital period, there is a paucity of approaches available for reduction of impairment beyond what is expected from spontaneous biological recovery. Thus, patients in the early stroke recovery period are not receiving the kind of training needed, at the requisite intensity and dose, to exploit a potential critical period of heightened brain plasticity that could maximize true recovery instead of just compensation. Here, we describe an ongoing pilot program to reconfigure the acute stroke unit experience to allow for a new emphasis on brain repair. More specifically, we have introduced a novel room-based video-gaming intervention; restorative neuroanimation, into the acute stroke hospital setting. This new intervention provides the opportunity for an extra hour(s) of high-intensity neurorestorative behavioral treatment that is complementary to conventional rehabilitation. To accomplish this, system redesign was required to insert this new treatment into the patient day, to properly stratify patients behaviorally and physiologically for the treatment, to optimize the digital therapeutic approach itself, and to maintain the impairment reduction after discharge.

Post-Ischemic Reorganization of Sensory Responses in Cerebral Cortex

Sensorimotor integration is critical for generating skilled, volitional movements. While stroke tends to impact motor function, there are also often associated sensory deficits that contribute to overall behavioral deficits. Because many of the cortico-cortical projections participating in the generation of volitional movement either target or pass-through primary motor cortex (in rats, caudal forelimb area; CFA), any damage to CFA can lead to a subsequent disruption in information flow. As a result, the loss of sensory feedback is thought to contribute to motor dysfunction even when sensory areas are spared from injury. Previous research has suggested that the restoration of sensorimotor integration through reorganization or de novo neuronal connections is important for restoring function. Our goal was to determine if there was crosstalk between sensorimotor cortical areas with recovery from a primary motor cortex injury. First, we investigated if peripheral sensory stimulation would evoke responses in the rostral forelimb area (RFA), a rodent homologue to premotor cortex. We then sought to identify whether intracortical microstimulation-evoked activity in RFA would reciprocally modify the sensory response. We used seven rats with an ischemic lesion of CFA. Four weeks after injury, the rats' forepaw was mechanically stimulated under anesthesia and neural activity was recorded in the cortex. In a subset of trials, a small intracortical stimulation pulse was delivered in RFA either individually or paired with peripheral sensory stimulation. Our results point to post-ischemic connectivity between premotor and sensory cortex that may be related to functional recovery. Premotor recruitment during the sensory response was seen with a peak in spiking within RFA after the peripheral solenoid stimulation despite the damage to CFA. Furthermore, stimulation evoked activity in RFA modulated and disrupted the sensory response in sensory cortex, providing additional evidence for the transmission of premotor activity to sensory cortex and the sensitivity of sensory cortex to premotor cortex's influence. The strength of the modulatory effect may be related to the extent of the injury and the subsequent reshaping of cortical connections in response to network disruption.

A phase III, multi-arm multi-stage covariate-adjusted response-adaptive randomized trial to determine optimal early mobility training after stroke (AVERT DOSE)

RATIONALE

The evidence base for acute post-stroke rehabilitation is inadequate and global guideline recommendations vary.

AIM

To define optimal early mobility intervention regimens for ischemic stroke patients of mild and moderate severity.

HYPOTHESES

Compared with a prespecified reference arm, the optimal dose regimen(s) will result in more participants experiencing little or no disability (mRS 0-2) at 3 months post-stroke (primary), fewer deaths at 3 months, fewer and less severe complications during the intervention period, faster recovery of unassisted walking, and better quality of life at 3 months (secondary). We also hypothesize that these regimens will be more cost-effective.

SAMPLE SIZE ESTIMATES

For the primary outcome, recruitment of 1300 mild and 1400 moderate participants will yield 80% power to detect a 10% risk difference.

METHODS AND DESIGN

Multi-arm multi-stage covariate-adjusted response-adaptive randomized trial of mobility training commenced within 48 h of stroke in mild (NIHSS < 7) and moderate (NIHSS 8-16) stroke patient strata, with analysis of blinded outcomes at 3 (primary) and 6 months. Eligibility criteria are broad, while excluding those with severe premorbid disability (mRS > 2) and hemorrhagic stroke. With four arms per stratum (reference arm retained throughout), only the single treatment arm demonstrating the highest proportion of favorable outcomes at the first stage will proceed to the second stage in each stratum, resulting in a final comparison with the reference arm. Three prognostic covariates of age, geographic region and reperfusion interventions, as well as previously observed mRS 0-2 responses inform the adaptive randomization procedure. Participants randomized receive prespecified mobility training regimens (functional task-specific), provided by physiotherapists/nurses until discharge or 14 days. Interventions replace usual mobility training. Fifty hospitals in seven countries (Australia, Malaysia, United Kingdom, Ireland, India, Brazil, Singapore) are expected to participate.

SUMMARY

Our novel adaptive trial design will evaluate a wider variety of mobility regimes than a traditional two-arm design. The data-driven adaptions during the trial will enable a more efficient evaluation to determine the optimal early mobility intervention for patients with mild and moderate ischemic stroke.

Acquisition of bipedal locomotion in a neuromusculoskeletal model with unilateral transtibial amputation

Adaptive locomotion is an essential behavior for animals to survive. The central pattern generator in the spinal cord is responsible for the basic rhythm of locomotion through sensory feedback coordination, resulting in energy-efficient locomotor patterns. Individuals with symmetrical body proportions exhibit an energy-efficient symmetrical gait on flat ground. In contrast, individuals with lower limb amputation, who have morphologically asymmetrical body proportions, exhibit asymmetrical gait patterns. However, it remains unclear how the nervous system adjusts the control of the lower limbs. Thus, in this study, we investigated how individuals with unilateral transtibial amputation control their left and right lower limbs during locomotion using a two-dimensional neuromusculoskeletal model. The model included a musculoskeletal model with 7 segments and 18 muscles, as well as a neural model with a central pattern generator and sensory feedback systems. Specifically, we examined whether individuals with unilateral transtibial amputation acquire prosthetic gait through a symmetric or asymmetric feedback control for the left and right lower limbs. After acquiring locomotion, the metabolic costs of transport and the symmetry of the spatiotemporal gait factors were evaluated. Regarding the metabolic costs of transportation, the symmetric control model showed values approximately twice those of the asymmetric control model, whereas both scenarios showed asymmetry of spatiotemporal gait patterns. Our results suggest that individuals with unilateral transtibial amputation can reacquire locomotion by modifying sensory feedback parameters. In particular, the model reacquired reasonable locomotion for activities of daily living by re-searching asymmetric feedback parameters for each lower limb. These results could provide insight into effective gait assessment and rehabilitation methods to reacquire locomotion in individuals with unilateral transtibial amputation.

Interpreting the CPASS Trial: Do Not Shift Motor Therapy to the Subacute Phase

The Critical Periods After Stroke Study (CPASS, n = 72) showed that, compared to controls, an additional 20 hours of intensive upper limb therapy led to variable gains on the Action Research Arm Test depending on when therapy was started post-stroke: the subacute group (2-3 months) improved beyond the minimal clinically important difference and the acute group (0-1 month) showed smaller but statistically significant improvement, but the chronic group (6-9 months) did not demonstrate improvement that reached significance. Some have misinterpreted CPASS results to indicate that all inpatient motor therapy should be shifted to outpatient therapy delivered 2 to 3 months post-stroke. Instead, however, CPASS argues for a large dose of motor therapy delivered continuously and cumulatively during the acute and subacute phases. When interpreting trials like CPASS, one must consider the substantial dose of early usual customary care (UCC) motor therapy that all participants received. CPASS participants averaged 27.9 hours of UCC occupational therapy (OT) during the first 2 months and 9.8 hours of UCC OT during the third and fourth months post-stroke. Any recovery experienced would therefore result not just from CPASS intensive motor therapy but the combined effects of experimental therapy plus UCC. Statistical limitations also did not allow direct comparisons of the acute and subacute group outcomes in CPASS. Instead of shifting inpatient therapy hours to the subacute phase, CPASS argues for preserving inpatient UCC. We also recommend conducting multi-site dosing trials to determine whether additional intensive motor therapy delivered in the first 2 to 3 months following inpatient rehabilitation can further improve outcomes.

Virtual reality in post-stroke neurorehabilitation - a systematic review and meta-analysis

BACKGROUND

Stroke is a neurological disorder and one of the leading causes of disability worldwide. The patient may lose the ability to adequately move the extremities, perceive sensations, or ambulate independently. Recent experimental studies have reported the beneficial influence of virtual reality training strategies on improving overall functional abilities for stroke survivors.

METHODS

Conducted a systematic review of the literature using the following keywords to retrieve the data: stroke, virtual reality, motor deficits, neurorehabilitation, cognitive impairments, and sensory deficits. A random-effect meta-analysis was performed for seven scales - one cognitive (MMSE) and six motor (Fugl-Meyer, Berg Balance Scale, Time up and go, Wolf motor function, 10 m walk, Brunnstrom score).

OBJECTIVE

To organize and compare all the available data regarding the effectiveness of virtual reality for stroke rehabilitation.

RESULTS

This literature reviewed 150 studies and included 46 for qualitative and 27 for quantitative analysis. There was no statistically significant difference between groups in MMSE score (MD = 0.24, 95%CI = ((-0.42) -(0.9)), p = .47, I² = 0%) and Fugl-Meyer score (MD = (-0.38), 95%CI = ((-12.88)-(12.11)), p = .95, I² = 98%) . The statistical significance was not reached in any of the other outcomes.

CONCLUSIONS

This review supports that stroke rehabilitation programs incorporating virtual reality are associated with improved functional outcomes, but there is no statistically significant difference compared to standard therapy.

EMAGINE-Study protocol of a randomized controlled trial for determining the efficacy of a frequency tuned electromagnetic field treatment in facilitating recovery within the subacute phase following ischemic stroke

Stroke is a leading cause of disability with limited effective interventions that improve recovery in the subacute phase. This protocol aims to evaluate the safety and efficacy of a non-invasive, extremely low-frequency, low-intensity, frequency-tuned electromagnetic field treatment [Electromagnetic Network Targeting Field (ENTF) therapy] in reducing disability and promoting recovery in people with subacute ischemic stroke (IS) with moderate-severe disability and upper extremity (UE) motor impairment. Following a sample-size adaptive design with a single interim analysis, at least 150 and up to 344 participants will be recruited to detect a 0.5-point (with a minimum of 0.33 points) difference on the modified Rankin Scale (mRS) between groups with 80% power at a 5% significance level. This ElectroMAGnetic field Ischemic stroke-Novel subacutE treatment (EMAGINE) trial is a multicenter, double-blind, randomized, sham-controlled, parallel two-arm study to be conducted at approximately 20 United States sites, and enroll participants with subacute IS and moderate-severe disability with UE motor impairment. Participants will be assigned to active (ENTF) or sham treatment, initiated 4-21 days after stroke onset. The intervention, applied to the central nervous system, is designed for suitability in multiple clinical settings and at home. Primary endpoint is change in mRS score from baseline to 90 days post-stroke. Secondary endpoints: change from baseline to 90 days post-stroke on the Fugl-Meyer Assessment - UE (lead secondary endpoint), Box and Block Test, 10-Meter Walk, and others, to be analyzed in a hierarchical manner. EMAGINE will evaluate whether ENTF therapy is safe and effective at reducing disability following subacute IS.

Trial registration

www.ClinicalTrials.gov, NCT05044507 (14 September 2021).

The pericontused cortex can support function early after TBI but it remains functionally isolated from normal afferent input

Traumatically injured brain functional connectivity (FC) is altered in a region-dependent manner with some regions functionally disconnected while others are hyperconnected after experimental TBI. Remote, homotopic cortical regions become hyperexcitable after injury, and we hypothesize that this results in increased trans-hemispheric cortical inhibition, preventing reorganization of the primary injured hemisphere. Previously we have shown that temporary silencing the contralesional cortex at 1wk normalizes affected forelimb behavioral use, but not at 4wks. To investigate the potential mechanism for this and to determine whether this occurs due to restoration of afferent pathway FC, and/or reorganization of brain circuits, we probed forelimb circuit function with sensorimotor task-evoked-fMRI, resting state fMRI seed-based analysis, and exploratory structural equation modelling (SEM) of directed causal connections due to forelimb task at 1 and 4wks post-injury after temporary, contralateral silencing with intraparenchymal injection of muscimol versus vehicle, as well as from sham rats. As predicted, silencing at 1wk and 4wks post-injury decimated the contralesional cortical forelimb map evoked by stimulation of the opposite, unaffected forelimb compared to vehicle-injected injured rats indicating the success of the intervention. Surprisingly however, this also resulted in activation of the pericontused cortex ipsilateral to the stimulated forelimb at 1wk, yet this same region could not be activated by directly stimulating the opposite, injury-affected forelimb. Underpinning this were significant increases in interhemispheric FC at the level of the cortex but decreases within subcortical regions. Causal SEM analysis confirmed increased corticothalamic connectivity and suggested changes from and to bilateral thalamus are important for the effect. At 4wks post-injury only cortical increases in FC were found in response to silencing indicating a less flexible brain, and ipsilesional cortex evoked activity was mostly absent. The absence of a reinstatement of ipsilesional evoked activity through normal pathways by temporary neuromodulation despite prior data showing behavioral improvements under the same conditions, indicates that while the pericontused cortex does retain function initially after injury, it is too functionally disconnected to be controlled by normal afferent input. More significant alterations in cross-brain FC during neuromodulation at 1wk compared to 4wk post-injury, suggest that more distributed brain activity accounts for prior behavior improvements in sensorimotor function, and that hemispheric imbalance in function is causally involved in early loss of sensorimotor function in this TBI model.

Test-Retest Reliability and Agreement of Single Pulse Transcranial Magnetic Stimulation (TMS) for Measuring Activity in Motor Cortex in Patients With Acute Ischemic Stroke

Background

Transcranial magnetic stimulation (TMS) is often used to examine neurophysiology. We aimed to investigate the inter-rater reliability and agreement of single pulse TMS in hospitalised acute ischemic stroke patients.

Methods

Thirty-one patients with first-time acute ischemic stroke (median age 72 (IQR 64-75), 35% females) underwent TMS motor threshold (MT) assessment in 4 muscles bilaterally, conducted by 1 of 2 physiotherapists. Test-retest reliability was evaluated using a two-way random effects model (2,1) absolute agreement-type Interclass Correlation Coefficient (ICC). Standard Error of Measurement (SEM) and Smallest Detectable Change (SDC) were used to evaluate agreement.

Results

Reliability, SEM, and SDC of TMS was found to be moderate in right opponens pollicis (0.78 [CI 95% 0.55-0.89], SEM: 4.51, SDC: 12.51), good in right vastus medialis and tibial anterior (0.88 [CI 95% 0.72-0.96], SEM: 2.89, SDC: 8.01 and 0.88 [CI 95% 0.76-0.94], SEM: 2.88, SDC: 7.98 respectively), and excellent in right and left biceps brachii (0.98 [CI 95% 0.96-0.99], SEM: 1.79 SDC: 4.96, and 0.94 [CI 95% 0.89-0.97], SEM: 2.17 SDC: 6.01), opponens pollicis (0.92 [CI 95% 0.83-0.96], SEM: 2.68 SDC: 8.26, vastus medialis (0.92 [CI 95% 0.84-0.96], SEM: 2.87 SDC: 7.95), and tibial anterior (0.93 [CI 95% 0.86-0.96], SEM: 2.51 SDC: 6.95).

Conclusion

The TMS demonstrated moderate to excellent inter-rater reliability confirming the ability of these measures to reliably discriminate between individuals in the current study sample. Improvements of less than 4.96 to 12.51 could be a result of measurement error and may therefore not be considered a true change.

Early, Intense Rehabilitation Fails to Improve Outcome After Intra-Striatal Hemorrhage in Rats

BACKGROUND

The formation and degradation of an intracerebral hemorrhage causes protracted cell death, and an extended window for intervention. Experimental studies find that rehabilitation mitigates late cell death, with accelerated hematoma clearance as a potential mechanism.

OBJECTIVE

We assessed whether early, intense, enriched rehabilitation (ER, environmental enrichment and massed skills training) enhances functional benefit, reduces brain injury, and augments hematoma clearance.

METHODS

In experiment 1, rats (n = 56) were randomized to intervention in the light (-L) or dark phase (-D) of their housing cycle, then to 10 days of ER or control (CON) treatment after collagenase-induced striatal intracerebral hemorrhage (ICH). ER rats were treated from 5 to 14 days after ICH. Behavior and residual hematoma volume was assessed on day 14. In experiment 2, rats (n = 72) were randomized to ER-D10, ER-D20, or CON-D. ER rats completed 10 or 20 days of training in the dark. Rats were euthanized on day 60 for histology. In both experiments, behavioral assessment was completed pre-ICH, pre-ER (day 4 post-ICH), and post-ER (experiment 1: days 13-14; experiment 2: days 16-17 and 30-31).

RESULTS

Reaching intensity was high but similar between ER-D10 and ER-L10. Unlike previous work, rehabilitation did not alter skilled reaching or hematoma resolution. Varying ER duration also did not affect reaching success or lesion volume.

CONCLUSIONS

In contrast to others, and under these conditions, our findings show that striatal ICH was generally unresponsive to rehabilitation. This highlights the difficulty of replicating and extending published work, perhaps owing to small inter-study differences.

Structural plasticity of motor cortices assessed by voxel-based morphometry and immunohistochemical analysis following internal capsular infarcts in macaque monkeys

Compensatory plastic changes in the remaining intact brain regions are supposedly involved in functional recovery following stroke. Previously, a compensatory increase in cortical activation occurred in the ventral premotor cortex (PMv), which contributed to the recovery of dexterous hand movement in a macaque model of unilateral internal capsular infarcts. Herein, we investigated the structural plastic changes underlying functional changes together with voxel-based morphometry (VBM) analysis of magnetic resonance imaging data and immunohistochemical analysis using SMI-32 antibody in a macaque model. Unilateral internal capsular infarcts were pharmacologically induced in 5 macaques, and another 5 macaques were used as intact controls for immunohistochemical analysis. Three months post infarcts, we observed significant increases in the gray matter volume (GMV) and the dendritic arborization of layer V pyramidal neurons in the contralesional rostral PMv (F5) as well as the primary motor cortex (M1). The histological analysis revealed shrinkage of neuronal soma and dendrites in the ipsilesional M1 and several premotor cortices, despite not always detecting GMV reduction by VBM analysis. In conclusion, compensatory structural changes occur in the contralesional F5 and M1 during motor recovery following internal capsular infarcts, and the dendritic growth of pyramidal neurons is partially correlated with GMV increase.

Repetitive transcranial magnetic stimulation of the primary motor cortex in stroke survivors-more than motor rehabilitation: A mini-review

Stroke is a leading cause of morbidity and mortality among elderly populations worldwide. During the early phase of stroke, restoring blood circulation is of utmost importance to protect neurons from further injury. Once the initial condition is stabilized, various rehabilitation techniques can be applied to help stroke survivors gradually regain their affected functions. Among these techniques, transcranial magnetic stimulation (TMS) has emerged as a novel method to assess and modulate cortical excitability non-invasively and aid stroke survivors in the rehabilitation process. Different cortical regions have been targeted using TMS based on the underlying pathology and distorted function. Despite the lack of a standard operational procedure, repetitive TMS (rTMS) of the primary motor cortex (M1) is considered a promising intervention for post-stroke motor rehabilitation. However, apart from the motor response, mounting evidence suggests that M1 stimulation can be employed to treat other symptoms such as dysphagia, speech impairments, central post-stroke pain, depression, and cognitive dysfunction. In this mini-review, we summarize the therapeutic uses of rTMS stimulation over M1 in stroke survivors and discuss the potential mechanistic rationale behind it.

Motor Cortex Plasticity During Functional Recovery Following Brain Damage

Although brain damage causes functional impairment, it is often followed by partial or total recovery of function. Recovery is believed to occur primarily because of brain plasticity. Both human and animal studies have significantly contributed to uncovering the neuronal basis of plasticity. Recent advances in brain imaging technology have enabled the investigation of plastic changes in living human brains. In addition, animal experiments have revealed detailed changes at the neural and genetic levels. In this review, plasticity in motor-related areas of the cerebral cortex, which is one of the most well-studied areas of the neocortex in terms of plasticity, is reviewed. In addition, the potential of technological interventions to enhance plasticity and promote functional recovery following brain damage is discussed. Novel neurorehabilitation technologies are expected to be established based on the emerging research on plasticity from the last several decades.

Optimal Intervention Timing for Robotic-Assisted Gait Training in Hemiplegic Stroke

This study was designed to determine the best intervention time (acute, subacute, and chronic stages) for Walkbot robot-assisted gait training (RAGT) rehabilitation to improve clinical outcomes, including sensorimotor function, balance, cognition, and activities of daily living, in hemiparetic stroke patients. Thirty-six stroke survivors (acute stage group (ASG), n = 11; subacute stage group (SSG), n = 15; chronic stage group (CSG), n = 10) consistently received Walkbot RAGT for 30 min/session, thrice a week, for 4 weeks. Six clinical outcome variables, including the Fugl–Meyer Assessment (FMA), Berg Balance Scale (BBS), Trunk Impairment Scale (TIS), Modified Barthel Index (MBI), Modified Ashworth Scale (MAS), and Mini-Mental State Examination, were examined before and after the intervention. Significant differences in the FMA, BBS, TIS, and MBI were observed between the ASG and the SSG or CSG. A significant time effect was observed for all variables, except for the MAS, in the ASG and SSG, whereas significant time effects were noted for the FMA, BBS, and TIS in the CSG. Overall, Walkbot RAGT was more favorable for acute stroke patients than for those with subacute or chronic stroke. This provides the first clinical evidence for the optimal intervention timing for RAGT in stroke.

Can Early Neuromuscular Rehabilitation Protocol Improve Disability after a Hemiparetic Stroke? A Pilot Study

Background: The impairment of limb function and disability are among the most important consequences of stroke. To date, however, little research has been done on the early rehabilitation trial (ERT) after stroke in these patients. The purpose of this study was to evaluate the impact of ERT neuromuscular protocol on motor function soon after hemiparetic stroke. The sample included twelve hemiparetic patients (54.3 ± 15.4 years old) with ischemic stroke (n = 7 control, n = 5 intervention patients). ERT was started as early as possible after stroke and included passive range of motion exercises, resistance training, assisted standing up, and active exercises of the healthy side of the body, in addition to encouraging voluntary contraction of affected limbs as much as possible. The rehabilitation was progressive and took 3 months, 6 days per week, 2–3 hours per session. Fugle-Meyer Assessment (FMA), Box and Blocks test (BBT) and Timed up and go (TUG) assessments were conducted. There was a significantly greater improvement in the intervention group compared to control: FMA lower limbs (p = 0.001), total motor function (p = 0.002), but no significant difference in FMA upper limb between groups (p = 0.51). The analysis of data related to BBT showed no significant differences between the experimental and control groups (p = 0.3). However, TUG test showed significant differences between the experimental and control groups (p = 0.004). The most important finding of this study was to spend enough time in training sessions and provide adequate rest time for each person. Our results showed that ERT was associated with improved motor function but not with the upper limbs. This provides a basis for a definitive trial.