Chronic Stroke Subjects Research Articles

Three dimensional innervation zone imaging in spastic muscles of stroke survivors

Objective. The outcome of botulinum toxin (BTX) therapy of post-stroke spasticity relies largely on accuracy of BTX injection to the proximity of innervation zones (IZs). Recently developed three-dimensional IZ imaging (3DIZI) is the only technique currently available to provide 3D distributions of IZs in vivo, yet its performance has not been validated under pathological conditions. Approach. The performance of 3DIZI was evaluated in the spastic biceps brachii muscles of four chronic stroke subjects. High-density surface electromyography (sEMG) and intramuscular electromyography (iEMG) were simultaneously recorded. The IZ location in the 3D space of the spastic biceps calculated using the 3DIZI technique from sEMG recordings were compared against the IZ location detected using intramuscular wires. Main results. 3DIZI successfully reconstructed the IZs in the 3D space of the spastic biceps of all four stroke subjects, with a localization error of 4.7 ± 2.7 mm, and specifically a depth error of 1.8 ± 0.4 mm. Significance. Results have demonstrated the robust performance of 3DIZI under pathological conditions, laying a solid foundation for clinical application of 3D source imaging in leading precise BTX injections for spasticity management.

Cortico-Muscular Coherence Modulated by High-Definition Transcranial Direct Current Stimulation in People With Chronic Stroke.

High-definition transcranial direct current stimulation (HD-tDCS) is a potential neuromodulation apparatus for stroke rehabilitation. However, its modulatory effects in stroke subjects is still not well understood. In this paper, the offline modulatory effects of HD-tDCS on the ipsilesional primary motor cortex were investigated by performing wrist isometric contraction tasks before and after HD-tDCS in eleven unilateral chronic stroke subjects using a synchronized HD-tDCS and electroencephalogram/electromyography measurement system. This paper is a randomized, single blinded, and sham-controlled crossover study. Each subject randomly received three HD-tDCS (anode, cathode, and sham) with at least one-week washout period. Online feedback-guided medium-level wrist isometric contraction tasks were conducted for the affected upper limbs before stimulation and 10, 30, and 50 min after the end of 10-min 1-mA HD-tDCS. The characteristics of corticomuscular coherence (CMC), cortical oscillation power spectral density, and power spectral entropy were analyzed during tasks and compared across all sessions and stimulation conditions. Anode HD-tDCS induced significant CMC changes in stroke subjects, while cathode and sham stimulation did not induce significant CMC changes. The largest neuromodulation effects were observed at 10 min immediately after anodal HD-tDCS.

Motor Unit Properties of the First Dorsal Interosseous in Chronic Stroke Subjects: Concentric Needle and Single Fiber EMG Analysis.

The purpose of this study was to better understand changes in motor unit electrophysiological properties in people with chronic stroke based on concentric needle electromyography (EMG) and single fiber EMG recordings. The first dorsal interosseous (FDI) muscle was studied bilaterally in eleven hemiparetic stroke subjects. A significant increase in mean fiber density (FD) was found in the paretic muscle compared with the contralateral side based on single fiber EMG (1.6 ± 0.2 vs. 1.3 ± 0.1, respectively, P = 0.003). There was no statistically significant difference between the paretic and contralateral sides in most concentric needle motor unit action potential (MUAP) parameters, such as amplitude (768.7 ± 441.7 vs. 855.0 ± 289.9 μV), duration (8.9 ± 1.8 vs. 8.68 ± 0.9 ms) and size index (1.2 ± 0.5 vs. 1.1 ± 0.3) (P > 0.18), nor was there a significant difference in single fiber EMG recorded jitter (37.0 ± 9.6 vs. 39.9 ± 10.6 μs, P = 0.45). The increase in FD suggests motor units of the paretic FDI have enlarged due to collateral reinnervation. However, sprouting might be insufficient to result in a statistically significant change in the concentric needle MUAP parameters. Single fiber EMG appears more sensitive than concentric needle EMG to reflect electrophysiological changes in motor units after stroke. Both single fiber and concentric needle EMG recordings may be necessary to better understand muscle changes after stroke, which is important for development of appropriate rehabilitation strategies. The results provide further evidence that motor units are remodeled after stroke, possibly in response to a loss of motoneurons.

Differentiated Effects of Robot Hand Training With and Without Neural Guidance on Neuroplasticity Patterns in Chronic Stroke.

Robot-assisted training combined with neural guided strategy has been increasingly applied to stroke rehabilitation. However, the induced neuroplasticity is seldom characterized. It is still uncertain whether this kind of guidance could enhance the long-term training effect for stroke motor recovery. This study was conducted to explore the clinical improvement and the neurological changes after 20-session guided or non-guided robot hand training using two measures: changes in brain discriminant ability between motor-imagery and resting states revealed from electroencephalography (EEG) signals and changes in brain network variability revealed from resting-state functional magnetic resonance imaging (fMRI) data in 24 chronic stroke subjects. The subjects were randomly assigned to receive either combined action observation (AO) with EEG-guided robot-hand training (RobotEEG_AO, n = 13) or robot-hand training without AO and EEG guidance (Robotnon−EEG_Text, n = 11). The robot hand in RobotEEG_AO group was activated only when significant mu suppression (8–12 Hz) was detected from subjects' EEG signals in ipsilesional hemisphere, while the robot hand in Robotnon−EEG_Text group was randomly activated regardless of their EEG signals. Paretic upper-limb motor functions were evaluated at three time-points: before, immediately after and 6 months after the interventions. Only RobotEEG_AO group showed a long-term significant improvement in their upper-limb motor functions while no significant and long-lasting training effect on the paretic motor functions was shown in Robotnon−EEG_Text group. Significant neuroplasticity changes were only observed in RobotEEG_AO group as well. The brain discriminant ability based on the ipsilesional EEG signals significantly improved after intervention. For brain network variability, the whole brain was first divided into six functional subnetworks, and significant increase in the temporal variability was found in four out of the six subnetworks, including sensory-motor areas, attention network, auditory network, and default mode network after intervention. Our results revealed the differences in the long-term training effect and the neuroplasticity changes following the two interventional strategies: with and without neural guidance. The findings might imply that sustainable motor function improvement could be achieved through proper neural guidance, which might provide insights into strategies for effective stroke rehabilitation. Furthermore, neuroplasticity could be promoted more profoundly by the intervention with proper neurofeedback, and might be shaped in relation to better motor skill acquisition.

Type 2 diabetes and older age contribute to elevated plasma microparticle concentrations independent of chronic stroke.

What is the central question of this study? What is the effect of chronic stroke on circulating microparticle populations, accounting for potential effects of age and type 2 diabetes? What is the main finding and its importance? Elevated concentrations of CD31+ /CD42b- and CD62E+ microparticles appear to be driven by type 2 diabetes but not chronic stroke and are associated with fasting glucose and triglyceride levels. Older age results in elevations in CD62E+ and CD34+ microparticle concentrations. These microparticles have been proposed as potential targets for diagnosing, treating and identifying the clinical progression and complications of type 2 diabetes. The elevated circulating concentration of endothelial microparticles (MPs) may provide an index of the extent and nature of cellular damage in chronic stroke. The purpose of this study was to determine the circulating concentrations of CD31+ /CD42b- , CD62E+ and CD34+ MPs in chronic stroke subjects, focusing on the effects of chronic stroke by comparison with both older adults without a history of stroke but with type 2 diabetes mellitus (T2DM) and older and young healthy controls. Plasma from three groups of sedentary older (50-75years) men and women (chronic stroke, T2DM or older healthy) as well as a group of younger (18-39years) healthy controls was isolated from fasting blood, and CD31+ /CD42b- , CD62E+ and CD34+ MPs were quantified using flow cytometry (n= 17/group). Concentrations of CD31+ /CD42b- and CD62E+ MPs were higher in the T2DM group (P< 0.05), but not chronic stroke, compared to older and younger healthy adults. CD62E+ MP and CD34+ MP concentrations were elevated in the older compared to younger adults (P< 0.05 for both). Sub-analyses excluding chronic stroke subjects who were also diagnosed with diabetes [stroke (diabetes- )] revealed lower CD31+ /CD42b- (P< 0.05) and CD62E+ (P= 0.08) MPs in the stroke (diabetes- ) group compared to the T2DM group. CD31+ /CD42b- MP and CD62E+ MP concentrations were each associated with fasting glucose levels and CD31+ /CD42b- MPs also were associated with triglyceride levels. As MPs have been proposed as potential targets for diagnosing, treating and identifying the clinical progression of T2DM, our study provides further support for the use of CD31+ /CD42b- and CD62E+ MPs in the clinical progression of T2DM and associated vascular complications.

Real-time Electromyography-driven Functional Electrical Stimulation Cycling System for Chronic Stroke Rehabilitation.

Stroke-induced lower extremity dysfunction has become a severe medical problem nowadays and effective rehabilitation methods are in great demand. In this work, a new real-time Electromyography-driven Functional Electrical Stimulation (FES) cycling system was developed to help chronic stroke patients with lower limb rehabilitation training. To evaluate the feasibility and effectiveness of this system, 3 chronic stroke subjects were recruited and each received 20 training sessions where real-time Electromyography (EMG) was used to interact with the cycling system. During the training, two typical metrics, averaged Area Under Torque (AUT) and maximal EMG amplitude, were adopted to measure the muscle strength changes of hamstring (HS). The training results showed that the two measurements of HS both significantly increased, especially the maximal EMG amplitude in the last trial was twice as much as that in the first trial, indicating paretic limb strength increment and functional recovery, which suggested that our system is effective and helpful in the stroke rehabilitation.

Low Gamma Band Cortico-muscular Coherence Inter-Hemisphere Difference following Chronic Stroke.

Brain oscillation and motor control process would change due to chronic stroke. Inter-hemisphere brain activation patterns may relate to motor related recovery. This study employed cortico-muscular coherence to explore cortical motor control process during wrist isometric contraction experiments of both affected and unaffected hands from chronic stroke subjects. Eleven chronic stroke subjects with moderate hand function involved in the experiments and each subject took three visits. Multitaper coherence estimation with bias-correction was performed to acquire cortico-muscular coherence, neuronal coherence source Localization was conducted to determine typical scalp motivation area during isometric contraction. Non-parametric permutation based multiple frequency bin statistics was utilized to compare the difference between two sides. The results demonstrated significant typical low gamma band inter-hemisphere disparity in cortico-muscular coherence between two sides after chronic stroke. The spatial topographical pattern and source Localization outcomes also supported these findings.

Feasibility of robot-based perturbed-balance training during treadmill walking in a high-functioning chronic stroke subject: a case-control study

BackgroundFor stroke survivors, balance deficits that persist after the completion of the rehabilitation process lead to a significant risk of falls. We have recently developed a balance-assessment robot (BAR-TM) that enables assessment of balancing abilities during walking. The purpose of this study was to test feasibility of using the BAR-TM in an experimental perturbed-balance training program with a selected high-functioning stroke survivor.MethodsA control and an individual with right-side chronic hemiparesis post-stroke were studied. The individual post-stroke underwent thirty sessions of balance-perturbed training that involved walking on an instrumented treadmill while the BAR-TM delivered random pushes to the participant’s pelvis; these pushes were in various directions, at various speeds, and had various perturbation amplitudes. We assessed kinematics, kinetics, electromyography, and spatio-temporal responses to outward-directed perturbations of amplitude 60 N (before training) and 60 N and 90 N (after training) commencing on contact of either the nonparetic-left foot (LL-NP/L perturbation) or the paretic-right foot (RR-P/R perturbation) while the treadmill was running at a speed of 0.4 m/s.ResultsBefore training, the individual post-stroke primarily responded to LL-NP/L perturbations with an in-stance response on the non-paretic leg in a similar way to the control participant. After training, the individual post-stroke added adequate stepping by making a cross-step with the paretic leg that enabled successful rejection of the perturbation at lower and higher amplitudes. Before training, the individual post-stroke primarily responded to RR-P/R perturbations with fast cross-stepping using the left, non-paretic leg while in-stance response was entirely missing. After training, the stepping with the non-paretic leg was supplemented by partially recovered ability to exercise in-stance responses on the paretic leg and this enabled successful rejection of the perturbation at lower and higher amplitudes. The assessed kinematics, kinetics, electromyography, and spatio-temporal responses provided insight into the relative share of each balancing strategy that the selected individual post-stroke used to counteract LL-NP/L and RR-P/R perturbations before and after the training.ConclusionsThe main finding of this case-control study is that robot-based perturbed-balance training may be a feasible approach. It resulted in an improvement the selected post-stroke participant’s ability to counteract outward-directed perturbations.Trial registrationClinicalTrials.gov Identifier: NCT03285919 – retrospectively registered.

Type 2 Diabetes and Older Age Contribute to Elevated Plasma Microparticle Concentrations

Endothelialmicroparticles (MPs) are small particles shed from the endothelium in responseto cellular activation and apoptosis and may serve as biomarkers of cardiovascular(CV) risk. The purpose of this study was to determine the effects of age, chronic stroke and type 2 diabetes mellitus (T2DM) on CD31+/CD42b−, CD62E+ andCD34+ MPs as biomarkers of endothelial apoptosis, activation and stress, respectively. Fasting blood samples were obtained from young (18–39 years old)and older (50–75 years old) healthy adults, as well as older adults with chronicstroke or T2DM (n=17/group). Cell‐free plasma was separated from fasting bloodsamples and incubated with antibodies against CD31, CD42b, CD62E or CD34 and MPconcentrations normalized to absolute number of events and quantified using anLSR II flow cytometer. Results showed that CD31+/CD42b− MP concentration was relatively low in young adults (36 ± 8 particles/μL) and not different in healthy older adults (71 ± 20 particles/μL P&gt;0.05); however, CD31+/CD42b− MP concentrations from chronic stroke subjects were 124% higher than younger adults. Additionally, T2DM subjects had 145% and 107% greater CD31+/CD42b−MP concentrations than healthy young and olderadults, respectively (P&lt;0.05 for both). Compared to young adults (211 ± 42 particles/μL), CD62E+ MP concentrations were significantly higher in all oldergroups (91%, 122% and 151%, in healthy, chronic stroke and T2DM subjects. respectively), with an additional effect of T2DM compared to healthy older adults (P&lt;0.05 for all). Similarly, there was an effect of age on CD34+ MP concentrations, with healthy older adults, chronic stroke, and T2DM subjects having significantly higher CD34+ MP concentrations (67%, 46% and 90%, respectively; P&lt;0.05 for all) compared to healthy younger individuals (20 ± 2 particles/μL). Because 41% of stroke subjects also had T2DM, we conducted analyses to distinguish the effects of T2DM and stroke in these participants. The diabetic stroke subjects had ~100% higher CD31+/CD42b− and CD62E+ MP concentrations compared to non‐diabetic stroke, whereas CD34+ MPs did not differ between diabetic and non‐diabetic stroke subjects. When diabetic subjects were removed from the stroke group and compared to the T2DM group there were 96% higher CD31+/CD42b− and 91% higher CD62E+ MP concentrations in the T2DM group (P&lt;0.05 for each) and MP levels in the non‐diabetic stroke group did not differ from healthy olderadults. Collectively, these results suggest that elevated concentrations of CD31+/CD42b− and CD62E+ MPs are driven by older age with an additional effect of T2DM but not stroke; whereas older age alone causes elevations in CD34+ MPs. Our findings indicate the potential for MPs as a novel biomarker for assessing endothelial health and CV risk in aging populations.Support or Funding InformationVeteransAffairs Maryland Exercise and Robotics Center of Excellence (MERCE)K23‐ AG040775(NIH and the American Federation for Aging Research);I01‐CX000730(Department of Veterans Affairs); Baltimore Veterans Affairs GeriatricResearch, Education and Clinical Center (GRECC),CareerDevelopment Award Number IK2 RX‐000944 from the United States (U.S) Department of Veterans Affairs Rehabilitation R&amp;D (Rehab RD) ServiceThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Abstract TP143: Evaluation of Knee Extensor Muscle Strength and Femoral Artery Blood Flow in Subacute Stroke Patients Admitted to Inpatient Rehabilitation - a Feasibility Study

Introduction: Weakness of the contralateral leg muscles commonly occurs following unilateral stroke. We and others have also shown that the femoral artery is atrophied in the paretic (P) limb of chronic stroke subjects (&gt;6 months post-stroke) compared to the non-paretic (NP) limb, and that both resting and hyperemic blood flow to the exercising muscle are dramatically reduced. Further, the hyperemic response positively correlates with leg strength and clinical measures of leg function. It is unknown if these changes in femoral artery diameter and peripheral blood flow are present in the subacute phase of stroke (&lt;30 days post-stroke). Hypothesis: Femoral artery diameter is smaller, and resting and hyperemic blood flow to exercising muscle is reduced in the P limb in subjects in the subacute phase of stroke admitted to inpatient rehabilitation. Methods: Stroke patients were tested within three days of admission to inpatient rehabilitation in a hospital setting. Isometric knee extensor maximal voluntary contractions (MVCs) were measured in both legs using a Biodex dynamometer. Superficial femoral artery diameter and blood flow were measured at rest and immediately following MVCs using Doppler ultrasound. Results: A pilot group of four subjects (1 male, 3 female) aged 68 ± 4 years (range 56-75 years) completed all study procedures on average 13 ± 5 days post ischemic stroke (range 7-24 days). All subjects had infarcts of the middle cerebral artery (3 right, 1 left). P leg knee extensor MVCs were lower compared to the NP leg (93.8 ± 25.5 Nm vs. 160.4 ± 33.2 Nm, respectively; p&lt;0.05). Superficial femoral artery diameter was smaller in the P leg compared to the NP leg (5.7 ± 0.4 mm vs. 6.0 ± 0.5 mm, respectively; p=0.06), and resting blood flow was reduced (172 ± 46 ml/min vs. 206 ± 54 ml/min, respectively; p&lt;0.05). Hyperemic blood flow in response to knee extensor MVCs was also lower in the P limb compared to the NP limb (239 ± 62 ml/min vs. 435 ± 67 ml/min, respectively; p&lt;0.05). Conclusions: We show feasibility of testing knee extensor muscle strength and peripheral blood flow in subacute stroke inpatients. Our preliminary data indicates that femoral artery atrophy has occurred in the P leg and that both resting and hyperemic blood flow to the P muscle are reduced.

The effects of upper and lower limb position on symmetry of vertical ground reaction force during sit-to-stand in chronic stroke subjects.

[Purpose] The purpose of this study was to evaluate the influence of arm and leg posture elements on symmetrical weight bearing during Sit to Stand tasks in chronic stroke patients. [Subjects and Methods] The subjects were diagnosed with stroke and 22 patients (15 males and 7 females) participated in this study. All participants performed Sit to Stand tasks on three foot postures and two arm postures. Two force plates were used to measure peak of vertical ground reaction force and symmetrical ratio to peak Fz. The data were analyzed using independent t-test and two-way repeated ANOVA. [Results] The results of this study are as follows: 1) Peak Fz placed more weight in non-paretic leg during Sit to Stand. 2) A symmetrical ratio to Peak Fz indicated significant difference between foot and arm posture, and had non-paretic limb supported on a step and paretic at ground level (STP) and grasped arm posture that lock fingers together with shoulder flexion by 90°(GA) (0.79 ± 0.09). [Conclusion] These results suggest that STP posture of the legs and GA posture of the arms should be able to increase the use of the paretic side during Sit to Stand behavior and induce normal Sit to Stand mechanism through the anterior tilt of the hip in clinical practices, by which loads onto the knee joint and the ankle joint can be reduced, and the trunk righting response can be promoted by making the back fully stretched. The outcome of this study is expected to be a reference for exercise or prognosis of Sit to Stand in stroke patients.

Changes in Electroencephalography Complexity using a Brain Computer Interface-Motor Observation Training in Chronic Stroke Patients: A Fuzzy Approximate Entropy Analysis.

Entropy-based algorithms have been suggested as robust estimators of electroencephalography (EEG) predictability or regularity. This study aimed to examine possible disturbances in EEG complexity as a means to elucidate the pathophysiological mechanisms in chronic stroke, before and after a brain computer interface (BCI)-motor observation intervention. Eleven chronic stroke subjects and nine unimpaired subjects were recruited to examine the differences in their EEG complexity. The BCI-motor observation intervention was designed to promote functional recovery of the hand in stroke subjects. Fuzzy approximate entropy (fApEn), a novel entropy-based algorithm designed to evaluate complexity in physiological systems, was applied to assess the EEG signals acquired from unimpaired subjects and stroke subjects, both before and after training. The results showed that stroke subjects had significantly lower EEG fApEn than unimpaired subjects (p < 0.05) in the motor cortex area of the brain (C3, C4, FC3, FC4, CP3, and CP4) in both hemispheres before training. After training, motor function of the paretic upper limb, assessed by the Fugl-Meyer Assessment-Upper Limb (FMA-UL), Action Research Arm Test (ARAT), and Wolf Motor Function Test (WMFT) improved significantly (p < 0.05). Furthermore, the EEG fApEn in stroke subjects increased considerably in the central area of the contralesional hemisphere after training (p < 0.05). A significant correlation was noted between clinical scales (FMA-UL, ARAT, and WMFT) and EEG fApEn in C3/C4 in the contralesional hemisphere (p < 0.05). This finding suggests that the increase in EEG fApEn could be an estimator of the variance in upper limb motor function improvement. In summary, fApEn can be used to identify abnormal EEG complexity in chronic stroke, when used with BCI-motor observation training. Moreover, these findings based on the fApEn of EEG signals also expand the existing interpretation of training-induced functional improvement in stroke subjects. The entropy-based analysis might serve as a novel approach to understanding the abnormal cortical dynamics of stroke and the neurological changes induced by rehabilitation training.

Neural Patterns of Reorganization after Intensive Robot-Assisted Virtual Reality Therapy and Repetitive Task Practice in Patients with Chronic Stroke.

Several approaches to rehabilitation of the hand following a stroke have emerged over the last two decades. These treatments, including repetitive task practice (RTP), robotically assisted rehabilitation and virtual rehabilitation activities, produce improvements in hand function but have yet to reinstate function to pre-stroke levels—which likely depends on developing the therapies to impact cortical reorganization in a manner that favors or supports recovery. Understanding cortical reorganization that underlies the above interventions is therefore critical to inform how such therapies can be utilized and improved and is the focus of the current investigation. Specifically, we compare neural reorganization elicited in stroke patients participating in two interventions: a hybrid of robot-assisted virtual reality (RAVR) rehabilitation training and a program of RTP training. Ten chronic stroke subjects participated in eight 3-h sessions of RAVR therapy. Another group of nine stroke subjects participated in eight sessions of matched RTP therapy. Functional magnetic resonance imaging (fMRI) data were acquired during paretic hand movement, before and after training. We compared the difference between groups and sessions (before and after training) in terms of BOLD intensity, laterality index of activation in sensorimotor areas, and the effective connectivity between ipsilesional motor cortex (iMC), contralesional motor cortex, ipsilesional primary somatosensory cortex (iS1), ipsilesional ventral premotor area (iPMv), and ipsilesional supplementary motor area. Last, we analyzed the relationship between changes in fMRI data and functional improvement measured by the Jebsen Taylor Hand Function Test (JTHFT), in an attempt to identify how neurophysiological changes are related to motor improvement. Subjects in both groups demonstrated motor recovery after training, but fMRI data revealed RAVR-specific changes in neural reorganization patterns. First, BOLD signal in multiple regions of interest was reduced and re-lateralized to the ipsilesional side. Second, these changes correlated with improvement in JTHFT scores. Our findings suggest that RAVR training may lead to different neurophysiological changes when compared with traditional therapy. This effect may be attributed to the influence that augmented visual and haptic feedback during RAVR training exerts over higher-order somatosensory and visuomotor areas.

The Immediate Effects of Posterior Pelvic Tilt with Taping on Pelvic Inclination, Gait Function and Balance in Chronic Stroke Patients*

PURPOSE: The purpose of this study is to identify the immediate effect of posterior pelvic tilt taping on anterior pelvic inclination, gait function, and balance in chronic stroke patients. METHODS: Fourteen chronic stroke subjects were enrolled in this study. Subjects who consented to participate in this cross-over experiment were assigned three interventions: posterior pelvic tilt taping, placebo taping, and no taping, in random order. After tape application, subjects were asked to complete: 1) Anterior pelvic tilt measurement, 2) 10-Meter Walk test, and 3) Limits of stability (LOS) test. To eliminate the learning effect of the tape after tearing off the tape, a 10 minute break was given between posterior pelvic tilt taping intervention and placebo taping intervention. RESULTS: Significant decreases were observed for the anterior pelvic inclination on both sides after posterior pelvic tilt taping application compared with placebo taping and no taping application (p .05). CONCLUSION: Posterior pelvic tilt taping in chronic stroke patients decreases the inappropriate anterior pelvic inclination immediately and improves gait function, but it has little effect on balance.

Brain plasticity following MI-BCI training combined with tDCS in a randomized trial in chronic subcortical stroke subjects: a preliminary study

Brain-computer interface-assisted motor imagery (MI-BCI) or transcranial direct current stimulation (tDCS) has been used in stroke rehabilitation, though their combinatory effect is unknown. We investigated brain plasticity following a combined MI-BCI and tDCS intervention in chronic subcortical stroke patients with unilateral upper limb disability. Nineteen patients were randomized into tDCS and sham-tDCS groups. Diffusion and perfusion MRI, and transcranial magnetic stimulation were used to study structural connectivity, cerebral blood flow (CBF), and corticospinal excitability, respectively, before and 4 weeks after the 2-week intervention. After quality control, thirteen subjects were included in the CBF analysis. Eleven healthy controls underwent 2 sessions of MRI for reproducibility study. Whereas motor performance showed comparable improvement, long-lasting neuroplasticity can only be detected in the tDCS group, where white matter integrity in the ipsilesional corticospinal tract and bilateral corpus callosum was increased but sensorimotor CBF was decreased, particularly in the ipsilesional side. CBF change in the bilateral parietal cortices also correlated with motor function improvement, consistent with the increased white matter integrity in the corpus callosum connecting these regions, suggesting an involvement of interhemispheric interaction. The preliminary results indicate that tDCS may facilitate neuroplasticity and suggest the potential for refining rehabilitation strategies for stroke patients.

Cross-cultural adaptation and measurement properties of the Brazilian version of the Exercise Preference Questionnaire(stroke)

BackgroundThe Exercise Preference Questionnaire (EPQ(stroke)) captures exercise preferences and measures personal factors, that influence motivation and adherence to exercise in stroke subjects. ObjectivesTo perform the cross-cultural adaptation of the EPQ(stroke) into the Brazilian-Portuguese language and to evaluate its measurement properties. MethodsThe EPQ(stroke) was cross-culturally adapted and primarily tested in 30 chronic stroke subjects. After the final version of the EPQ(stroke)-Brazil was created, its test–retest reliability was verified, using Kappa indices and intra-class correlation coefficients (ICCs) (n=50), and internal consistency was verified using Cronbach's alpha coefficients (n=101). Construct validity was assessed using exploratory factor analysis (n=101), content validity using the content validity index (CVI) (n=8), and face validity using the rate of agreement regarding the clarity, wording, ability to answer the questions, and lay-out and style of the questionnaire with two groups, including individuals with stroke (n=81) and multidisciplinary health professionals (n=32). ResultsThe pre-final version required revisions (items 9, 29, and 30) and, after another pre-test, it was shown to be appropriate. The Kappa indices ranged from 0.58 to 0.95; the ICCs from 0.35 to 0.93, and the Cronbach's alpha coefficient was 0.82 (0.768–0.869 CI), showing adequate internal consistency. The exploratory factor analysis and CVI confirmed the validity of the EPQ(stroke)-Brazil. The rate of agreement was greater than 80% for both groups. ConclusionThe EPQ(stroke)-Brazil was found to be a valid and reliable measure for verifying exercise preferences of Brazilian individuals with stroke.

Robot-assisted end-effector-based gait training in chronic stroke patients: Amulticentric uncontrolled observational retrospective clinical study.

Until now studies report inconclusive results as regards the effectiveness of exclusive use of robot-assisted training and clinical indications in stroke patients. To evaluate if the only robot-assisted end-effector-based gait training can be feasible in chronic stroke subjects in terms of gait recovery. Five rehabilitation centers participated and one hundred chronic post-stroke patients were recruited. Patients underwent a robot-assisted end-effector-based gait training as only rehabilitation treatment.6 Minute Walk Test, 10 Meter Walk Test, Timed Up and Go test, Modified Ashworth Scale, Motricity Index, Functional Ambulation Classification (FAC) and Walking Handicap Scale were used as outcome clinical measure. Patients were divided into two groups: those assessed as FAC <3 (Group 1) and as FAC ≥ 3 (Group 2). Statistically significant changes were observed in each clinical outcome measure. Significant changes were observed in Group 1 and in Group 2. Significant percentages of patients achieved Minimally Clinically Important Difference in 6 Minute Walk Test in Group 2 and Timed Up and Go test in Group 1. Chronic stroke patients exposed to only robot-assisted end-effector-based gait training showed significant improvements in global motor performances, gait endurance, balance and coordination, lower limbs strength and even spasticity.

Caracterização da participação social de indivíduos na fase crônica pós-acidente vascular encefálico

O objetivo foi descrever e comparar diferenças na restrição na participação social de indivíduos após acidente vascular encefálico (AVE) na fase crônica, considerando as deficiências, limitações em mobilidade e fatores pessoais. A restrição na participação social foi mensurada pelo LIFE-H 3.1-Brasil; as deficiências pela Escala de Depressão Geriátrica e Escala de Fugl-Meyer (EFM); as limitações em mobilidade pela velocidade de marcha e Timed Up &amp; Go (TUG) e os fatores pessoais incluíram sexo, idade, situação familiar e tempo de evolução pós-AVE. Observou-se restrição significativa na área de recreação. Em geral, restrições na participação social foram observadas em participantes com escores ≤28 na EFM-membro inferior, sintomas de depressão, marcha comunitária limitada, risco de quedas e tempo de evolução ≤5 anos. Aqueles com escores ≤45 na EFM-membro superior apresentaram maior restrição em algumas áreas das atividades diárias. As mulheres apresentaram maior restrição em papéis sociais. Os resultados sugerem que deficiências e limitações relacionadas aos membros inferiores, sintomas depressivos e tempo de evolução devem ser considerados na avaliação, quando o objetivo da reabilitação for aumentar a participação social de indivíduos pós-AVE.

Design and test of an automated version of the modified Jebsen test of hand function using Microsoft Kinect

BackgroundThe present paper describes the design and evaluation of an automated version of the Modified Jebsen Test of Hand Function (MJT) based on the Microsoft Kinect sensor.MethodsThe MJT was administered twice to 11 chronic stroke subjects with varying degrees of hand function deficits. The test times of the MJT were evaluated manually by a therapist using a stopwatch, and automatically using the Microsoft Kinect sensor. The ground truth times were assessed based on inspection of the video-recordings. The agreement between the methods was evaluated along with the test-retest performance.ResultsThe results from Bland-Altman analysis showed better agreement between the ground truth times and the automatic MJT time evaluations compared to the agreement between the ground truth times and the times estimated by the therapist. The results from the test-retest performance showed that the subjects significantly improved their performance in several subtests of the MJT, indicating a practice effect.ConclusionsThe results from the test showed that the Kinect can be used for automating the MJT.

Home-Based Therapy After Stroke Using the Hand Spring Operated Movement Enhancer (HandSOME).

In previous work, we developed a lightweight wearable hand exoskeleton (Hand Spring Operated Movement Enhancer) that improves range of motion and function in laboratory testing. In this pilot study, we added the ability to log movement data for extended periods and recruited ten chronic stroke subjects to use the device during reach and grasp task practice at home for 1.5 h/day, five days per week, and for four weeks. Seven subjects completed the study, performing 448 ± 651 hand movements per training day. After training, impairment was reduced (Fugl-Meyer test; gain = 4.9 ± 4.1; p = .039) and function was improved (Action Research Arm Test; gain = 3.3 ± 2.6; p = .032). There was a significant correlation between gains in the Action Research Arm Test and the number of movements during training (r = 0.90; p = .005). Proximal arm control also improved, as evidenced by a significant reduction in the reach path ratio (p = 0.038). Five subjects responded well to the treatment, having gains of six points or more on the Fugl-Meyer or action research arm test, and achieving significant gains in digit extension (gain = 19.8 ± 10.2°; p = 0.024). However, all of the gains that were significant immediately after training were no longer significant at the three month follow-up. This treatment approach appears promising, but longer periods of home training may be needed to achieve sustainable gains.