Severe Hemiparetic Stroke Research Articles

Quadriceps Thickness and Echo Intensity Predict Gait Independence in Individuals with Severe and Mild Hemiparetic Stroke

Introduction: Smaller muscle size and higher adipose tissue ratio of the quadriceps femoris are often observed after stroke. However, it is unclear whether muscle size and the intramuscular fat ratio of the quadriceps measured with ultrasonography (US) reflect gait independence in individuals with mild or severe hemiparetic stroke. Objective: The present study was performed to examine the relationships of gait independence with muscle thickness (MT) and echo intensity (EI) of the quadriceps femoris in individuals with hemiparesis after stroke. Methods: We examined 43 individuals with hemiparetic stroke. We assessed functional independence measure (FIM) gait scores and measured thickness and EI of the quadriceps using US. The relationships of FIM gait scores with MT and EI were examined using Spearman’s correlation coefficients in mild (n = 21) and severe (n = 22) hemiparetic stroke groups. Results: In the mild hemiparetic group, FIM gait scores were correlated with paretic limb MT (rho = 0.60, p < 0.01) and EI (rho = −0.57, p < 0.01). In the severe hemiparetic group, FIM gait scores were correlated with paretic limb MT (rho = 0.67, p < 0.01) and EI (rho = −0.43, p < 0.05), as well as non-paretic limb MT (rho = 0.86, p < 0.01) and EI (rho = −0.56, p < 0.01). Conclusions: Quadriceps thickness and EI were associated with the degree of gait independence. Atrophy and increased intramuscular fat of the quadriceps may be limiting factors for achieving gait independence.

Evaluating the Effectiveness and Safety of the Electroencephalogram-Based Brain-Machine Interface Rehabilitation System for Patients With Severe Hemiparetic Stroke: Protocol for a Randomized Controlled Trial (BEST-BRAIN Trial).

BackgroundWe developed a brain-machine interface (BMI) system for poststroke patients with severe hemiplegia to detect event-related desynchronization (ERD) on scalp electroencephalogram (EEG) and to operate a motor-driven hand orthosis combined with neuromuscular electrical stimulation. ERD arises when the excitability of the ipsi-lesional sensorimotor cortex increases.ObjectiveThe aim of this study was to evaluate our hypothesis that motor training using this BMI system could improve severe hemiparesis that is resistant to improvement by conventional rehabilitation. We, therefore, planned and implemented a randomized controlled clinical trial (RCT) to evaluate the effectiveness and safety of intensive rehabilitation using the BMI system.MethodsWe conducted a single blind, multicenter RCT and recruited chronic poststroke patients with severe hemiparesis more than 90 days after onset (N=40). Participants were randomly allocated to the BMI group (n=20) or the control group (n=20). Patients in the BMI group repeated 10-second motor attempts to operate EEG-BMI 40 min every day followed by 40 min of conventional occupational therapy. The interventions were repeated 10 times in 2 weeks. Control participants performed a simple motor imagery without servo-action of the orthosis, and electrostimulation was given for 10 seconds for 40 min, similar to the BMI intervention. Overall, 40 min of conventional occupational therapy was also given every day after the control intervention, which was also repeated 10 times in 2 weeks. Motor functions and electrophysiological phenotypes of the paretic hands were characterized before (baseline), immediately after (post), and 4 weeks after (follow-up) the intervention. Improvement in the upper extremity score of the Fugl-Meyer assessment between baseline and follow-up was the main outcome of this study.ResultsRecruitment started in March 2017 and ended in July 2018. This trial is currently in the data correcting phase. This RCT is expected to be completed by October 31, 2018.ConclusionsNo widely accepted intervention has been established to improve finger function of chronic poststroke patients with severe hemiparesis. The results of this study will provide clinical data for regulatory approval and novel, important understanding of the role of sensory-motor feedback based on BMI to induce neural plasticity and motor recovery.Trial RegistrationUMIN Clinical Trials Registry UMIN000026372; https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi? recptno=R000030299 (Archived by WebCite at http://www.webcitation.org/743zBJj3D)International Registered Report Identifier (IRRID)DERR1-10.2196/12339

Stepwise intervention for proximal and distal upper extremity motor function in patients with chronic stroke: A report of 2 cases

Upper extremity (UE) dysfunction is a common problem in patients with stroke. Recently, several neurorehabilitation approaches have been developed to improve the UE motor function (Langphorene P. Lancet Neurol , 2009). However, most approaches target either proximal or distal UE motor function, although interventions targeting both portions are necessary to restore functional UE in actual daily life. Therefore, we conducted stepwise intervention for both shoulder and finger function to improve UE motor function. Two stroke patients with severe hemiparetic stroke participated in the study. Firstly, we attempted to improve shoulder function using brain machine interface (BMI) technology for 7 days ( Fig. 1 ). After the shoulder BMI training, a combination of motor imagery and electrical stimulation (MI + ES) was conducted to improve finger function for 10 days ( Fig. 2 ). Motor function of the affected UE was assessed with motor items of the Fugl–Meyer assessment UE motor score (FMA-UE). FMA-UE consists of 4 categories (A: Shoulder/Elbow/Forearm; B: Wrist; C: Hand; D: Coordination) and has a maximum score of 66. The FMA-UE score increased remarkably after the stepwise intervention (Patient A: 17→33; Patient B: 11→25). The effect of shoulder BMI training is shown in Fig. 3 . It became possible for patients to raise their arms above the shoulder position after the shoulder BMI training. Patients’ UE motor function was also further improved by the subsequent MI + ES intervention. The improvement in UE motor function with our stepwise intervention for proximal and distal motor functions greatly exceeded the minimal clinically important difference in the subjects of this study.

Neuromodulatory Inputs to Motoneurons Contribute to the Loss of Independent Joint Control in Chronic Moderate to Severe Hemiparetic Stroke.

In chronic hemiparetic stroke, increased shoulder abductor activity causes involuntary increases in elbow, wrist, and finger flexor activation, an abnormal muscle coactivation pattern known as the flexion synergy. Recent evidence suggests that flexion synergy expression may reflect recruitment of contralesional cortico-reticulospinal motor pathways following damage to the ipsilesional corticospinal tract. However, because reticulospinal motor pathways produce relatively weak post-synaptic potentials in motoneurons, it is unknown how preferential use of these pathways could lead to robust muscle activation. Here, we hypothesize that the descending neuromodulatory component of the ponto-medullary reticular formation, which uses the monoaminergic neurotransmitters norepinephrine and serotonin, serves as a gain control mechanism to facilitate motoneuron responses to reticulospinal motor commands. Thus, inhibition of the neuromodulatory component would reduce flexion synergy expression by disfacilitating spinal motoneurons. To test this hypothesis, we conducted a pre-clinical study utilizing two targeted neuropharmacological probes and inert placebo in a cohort of 16 individuals with chronic hemiparetic stroke. Test compounds included Tizanidine (TIZ), a noradrenergic α2 agonist and imidazoline ligand selected for its ability to reduce descending noradrenergic drive, and Isradipine, a dihyropyridine calcium-channel antagonist selected for its ability to post-synaptically mitigate a portion of the excitatory effects of monoamines on motoneurons. We used a previously validated robotic measure to quantify flexion synergy expression. We found that Tizanidine significantly reduced expression of the flexion synergy. A predominantly spinal action for this effect is unlikely because Tizanidine is an agonist acting on a baseline of spinal noradrenergic drive that is likely to be pathologically enhanced post-stroke due to increased reliance on cortico-reticulospinal motor pathways. Although spinal actions of TIZ cannot be excluded, particularly from Group II pathways, our finding is consistent with a supraspinal action of Tizanidine to reduce descending noradrenergic drive and disfacilitate motoneurons. The effects of Isradipine were not different from placebo, likely related to poor central bioavailability. These results support the hypothesis that the descending monoaminergic component of the ponto-medullary reticular formation plays a key role in flexion synergy expression in chronic hemiparetic stroke. These results may provide the basis for new therapeutic strategies to complement physical rehabilitation.

Flexion synergy overshadows flexor spasticity during reaching in chronic moderate to severe hemiparetic stroke.

Pharmaceutical intervention targets arm flexor spasticity with an often-unsuccessful goal of improving function. Flexion synergy is a related motor impairment that may be inadvertently neglected. Here, flexor spasticity and flexion synergy are disentangled to determine their contributions to reaching dysfunction. Twenty-six individuals participated. A robotic device systematically modulated shoulder abduction loading during ballistic reaching. Elbow muscle electromyography data were partitioned into windows delineated by elbow joint velocity allowing for the separation of synergy- and spasticity-related activation. Reaching velocity decreased with abduction loading (p<0.001) such that velocity was 30% slower when lifting the arm at 50% of abduction strength compared to when arm weight was supported. Abnormal flexion synergy increased with abduction loading (p<0.001) such that normalized activation ranged from a median (interquartile range) of 0.07 (0.03-0.12) when arm weight was supported to 0.19 (0.12-0.40) when actively lifting (large effect size, d=0.59). Flexor spasticity was detected during reaching (p=0.016) but only when arm weight was supported (intermediate effect size, d=0.33). Flexion synergy is the predominant contributor to reaching dysfunction while flexor spasticity appears only relevant during unnaturally occurring passively supported movement. Interventions targeting flexion synergy should be leveraged in future stroke recovery trials.

A new therapeutic application ofbrain-machine interface (BMI) training followed by hybrid assistive neuromuscular dynamic stimulation (HANDS) therapy forpatients with severe hemiparetic stroke: A proof of concept study.

Hybrid assistive neuromuscular dynamic stimulation (HANDS) therapy improved paretic upper extremity motor function in patients with severe to moderate hemiparesis. We hypothesized that brain machine interface (BMI) training would be able to increase paretic finger muscle activity enough to apply HANDS therapy in patients with severe hemiparesis, whose finger extensor was absent. The aim of this study was to assess the efficacy of BMI training followed by HANDS therapy in patients with severe hemiparesis. Twenty-nine patients with chronic stroke who could not extend their paretic fingers were participated this study. We applied BMI training for 10 days at 40 min per day. The BMI detected the patients' motor imagery of paretic finger extension with event-related desynchronization (ERD) over the affected primary sensorimotor cortex, recorded with electroencephalography. Patients wore a motor-driven orthosis, which extended their paretic fingers and was triggered with ERD. When muscle activity in their paretic fingers was detected with surface electrodes after 10 days of BMI training, we applied HANDS therapy for the following 3 weeks. In HANDS therapy, participants received closed-loop, electromyogram-controlled, neuromuscular electrical stimulation (NMES) combined with a wrist-hand splint for 3 weeks at 8 hours a day. Before BMI training, after BMI training, after HANDS therapy and 3month after HANDS therapy, we assessed Fugl-Meyer Assessment upper extremity motor score (FMA) and the Motor Activity Log14-Amount of Use (MAL-AOU) score. After 10 days of BMI training, finger extensor activity had appeared in 21 patients. Eighteen of 21 patients then participated in 3 weeks of HANDS therapy. We found a statistically significant improvement in the FMA and the MAL-AOU scores after the BMI training, and further improvement was seen after the HANDS therapy. Combining BMI training with HANDS therapy could be an effective therapeutic strategy for severe UE paralysis after stroke.

Brain-computer interface training combined with transcranial direct current stimulation in patients with chronic severe hemiparesis: Proof of concept study.

Brain-computer interface technology has been applied to stroke patients to improve their motor function. Event-related desynchronization during motor imagery, which is used as a brain-computer interface trigger, is sometimes difficult to detect in stroke patients. Anodal transcranial direct current stimulation (tDCS) is known to increase event-related desynchronization. This study investigated the adjunctive effect of anodal tDCS for brain-computer interface training in patients with severe hemiparesis. Eighteen patients with chronic stroke. A non-randomized controlled study. Subjects were divided between a brain-computer interface group and a tDCS- brain-computer interface group and participated in a 10-day brain-computer interface training. Event-related desynchronization was detected in the affected hemisphere during motor imagery of the affected fingers. The tDCS-brain-computer interface group received anodal tDCS before brain-computer interface training. Event-related desynchronization was evaluated before and after the intervention. The Fugl-Meyer Assessment upper extremity motor score (FM-U) was assessed before, immediately after, and 3 months after, the intervention. Event-related desynchronization was significantly increased in the tDCS- brain-computer interface group. The FM-U was significantly increased in both groups. The FM-U improvement was maintained at 3 months in the tDCS-brain-computer interface group. Anodal tDCS can be a conditioning tool for brain-computer interface training in patients with severe hemiparetic stroke.

No. 96 Improved Upper Extremity Functions in Patients With Chronic Severe Hemiparetic Stroke With Brain Machine Interface (BMI) Training Followed by Hybrid Assistive Neuromuscular Stimulation (HANDS) Therapy

PM&RVolume 6, Issue 8S2 p. S115-S115 Poster Presentation No. 96 Improved Upper Extremity Functions in Patients With Chronic Severe Hemiparetic Stroke With Brain Machine Interface (BMI) Training Followed by Hybrid Assistive Neuromuscular Stimulation (HANDS) Therapy Atsuko Horie, Atsuko HorieSearch for more papers by this authorToshiyuki Fujiwara MD PhD, Toshiyuki Fujiwara MD PhDSearch for more papers by this authorMeigen Liu MD PhD, Meigen Liu MD PhDSearch for more papers by this authorKoru Abe OTR, Koru Abe OTRSearch for more papers by this author Atsuko Horie, Atsuko HorieSearch for more papers by this authorToshiyuki Fujiwara MD PhD, Toshiyuki Fujiwara MD PhDSearch for more papers by this authorMeigen Liu MD PhD, Meigen Liu MD PhDSearch for more papers by this authorKoru Abe OTR, Koru Abe OTRSearch for more papers by this author First published: 18 September 2014 https://doi.org/10.1016/j.pmrj.2014.08.228Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume6, Issue8S28th World Congress of the International Society of Physical & Rehabilitation Medicine (ISPRM)August 2014Pages S115-S115 RelatedInformation

P247: Brain-machine interface training combined with transcranial direct current stimulation in patients with chronic severe hemiparesis: proof of concept study

Objective: Brain–computer interface technology has been applied to stroke patients to improve their motor function. Event-related desynchronization during motor imagery, which is used as a brain–computer interface trigger, is sometimes difficult to detect in stroke patients. Anodal transcranial direct current stimulation (tDCS) is known to increase event-related desynchronization. This study investigated the adjunctive effect of anodal tDCS for brain–computer interface training in patients with severe hemiparesis. Subjects: Eighteen patients with chronic stroke. Design: A non-randomized controlled study. Methods: Subjects were divided between a brain–computer interface group and a tDCS-brain–computer interface group and participated in a 10-day brain–computer interface training. Event-related desynchronization was detected in the affected hemisphere during motor imagery of the affected fingers. The tDCS-brain–computer interface group received anodal tDCS before brain–computer interface training. Event-related desynchronization was evaluated before and after the intervention. The Fugl-Meyer Assessment upper extremity motor score (FM-U) was assessed before, immediately after, and 3 months after, the intervention. Results: Event-related desynchronization was significantly increased in the tDCS- brain–computer interface group. The FM-U was significantly increased in both groups. The FM-U improvement was maintained at 3 months in the tDCSbrain–computer interface group. Conclusion: Anodal tDCS can be a conditioning tool for brain–computer interface training in patients with severe hemiparetic stroke.

52. Modulation of event related desynchronization during motor imagery with transcranial direct current stimulation (tDCS) in patients with chronic hemiparetic stroke

Electroencephalogram-based brain–computer interface (BCI) has been developed as a new neurorehabilitative tool for patients with severe hemiparesis. However, its application has been limited because of difficulty detecting stable brain signals from the affected hemisphere. It has been reported that transcranial direct current stimulation (tDCS) can modulate event-related desynchronization (ERD) in healthy persons. The objective of this study was to test the hypothesis that anodal tDCS could modulate ERD in patients with severe hemiparetic stroke. The participants were six patients with chronic hemiparetic stroke (mean age, 56.8 ± 9.5 years; mean time from the onset, 70.0 ± 19.6 months; Fugl-Meyer Assessment upper extremity motor score, 30.8 ± 16.5). We applied anodal tDCS (10 min, 1 mA) and sham stimulation over the affected primary motor cortex in a random order. ERD of the mu rhythm (mu ERD) with motor imagery of extension of the affected finger was assessed before and after anodal tDCS and sham stimulation. Mu ERD of the affected hemisphere increased significantly after anodal tDCS, whereas it did not change after sham stimulation. Our results show that anodal tDCS can increase mu ERD in patients with hemiparetic stroke, indicating that anodal tDCS could be used as a conditioning tool for BCI in stroke patients.

Modulation of event-related desynchronization during motor imagery with transcranial direct current stimulation (tDCS) in patients with chronic hemiparetic stroke

Electroencephalogram-based brain-computer interface (BCI) has been developed as a new neurorehabilitative tool for patients with severe hemiparesis. However, its application has been limited because of difficulty detecting stable brain signals from the affected hemisphere. It has been reported that transcranial direct current stimulation (tDCS) can modulate event-related desynchronization (ERD) in healthy persons. The objective of this study was to test the hypothesis that anodal tDCS could modulate ERD in patients with severe hemiparetic stroke. The participants were six patients with chronic hemiparetic stroke (mean age, 56.8±9.5years; mean time from the onset, 70.0±19.6months; Fugl-Meyer Assessment upper extremity motor score, 30.8±16.5). We applied anodal tDCS (10min, 1mA) and sham stimulation over the affected primary motor cortex in a random order. ERD of the mu rhythm (mu ERD) with motor imagery of extension of the affected finger was assessed before and after anodal tDCS and sham stimulation. Mu ERD of the affected hemisphere increased significantly after anodal tDCS, whereas it did not change after sham stimulation. Our results show that anodal tDCS can increase mu ERD in patients with hemiparetic stroke, indicating that anodal tDCS could be used as a conditioning tool for BCI in stroke patients.

Modulation of Event-related Desynchronization duringMotor Imagery with Transcranial Direct Current Stimulationin a Patient with Severe Hemiparetic Stroke: A Case Report

Recently, surface electroencephalogram (EEG)-based brain-machine interfaces (BMI) have been used for people with disabilities. As a BMI signal source, event-related desynchronization of alpha-band EEG (8-13 Hz) during motor imagery (mu ERD), which is interpreted as desynchronized activities of the activated neurons, is commonly used. However, it is often difficult for patients with severe hemiparesis to produce mu ERD of sufficient strength to activate BMI. Therefore, whether it is possible to modulate mu ERD during motor imagery with anodal transcranial direct-current stimulation (tDCS) was assessed in a severe left hemiparetic stroke patient. EEG was recorded over the primary motor cortex (M1), and mu ERD during finger flexion imagery was measured before and after a 5-day course of tDCS applied to M1. The ERD recorded over the affected M1 increased significantly after tDCS intervention. Anodal tDCS may increase motor cortex excitability and potentiate ERD during motor imagery in patients with severe hemiparetic stroke.

Rehabilitation of Reaching After Stroke: Comparing 2 Training Protocols Utilizing Trunk Restraint

Background and Purpose . Task-related training (TRT) but not resistive exercise (RE) was found to improve the path of the hand of a hemiparetic upper extremity when reaching to targets. Forward movement of the trunk, however, compensated for the poststroke motor impairment. Prior studies also demonstrated that short-term practice of reaching to grasp objects with truncal motion restrained (compared to unrestrained practice) increased elbow extension, lessened compensatory trunk movement, and improved interjoint coordination during performance with the trunk unrestrained. Objective. To determine the effects of TRT and RE on unrestrained reaching following extended practice in which compensatory truncal motion was limited. Methods. Using a restraining device to reduce movement of the trunk, hemiparetic patients with moderately severe motor impairment were given 12 sessions over 4 weeks of TRT (n = 5) or RE (n = 6). Reaching when the trunk was not restrained to targets located ipsilateral, midline, and contralateral to the impaired arm was tested before and 2 days after training by 3D kinematic analyses. Results. After both training protocols, kinematic analysis showed that trunk flexion decreased (P < .01, η2 = .53) scapular motion shifted toward protraction (P < .01, η2 = .57) and elbow extension increased (P < .04, η2 = .39). Only after TRT did the path of the hand straighten (P < .02, η2 = .46), deceleration time decrease (P < .03, η2 = .44), and, at the difficult ipsilateral target, shoulder flexion increase (P < .03, η 2 = .31). Conclusions. Training that restricted compensatory truncal motion during TRT improved the precision of reaching more than during RE. Truncal restraint during rehabilitation of reaching may be an effective therapeutic strategy in patients with moderately severe hemiparetic stroke, especially when combined with TRT.

PRELIMINARY RESULTS FOR A TARGETED INTERVENTION FOR IMPROVING REACHING RANGE OF MOTION IN SEVERE HEMIPARETIC STROKE USING THE ARM

Purpose/Hypothesis: Abnormal upper extremity coordination can be expressed in the form of atypical muscle synergies that result in limited and stereotypic movement patterns such that when an individual with hemiparetic stroke attempts to support the arm against gravity there is a strong coupling with elbow flexion. These movement constraints are functionally disabling. While quantification of stroke-related impairments such as abnormal shoulder/elbow torque coupling has been thoroughly described in our laboratory under isometric and dynamic conditions, only recently have striking advances in rehabilitation robotics enabled us to develop a rehabilitation protocol that specifically targets discoordination in a quantifiable and repeatable fashion. We have developed and are employing the Arm Coordination Training 3D Device (ACT3D). This report documents preliminary evidence supporting the efficacy of an impairment-specific dynamic strengthening protocol for a group of individuals with chronic stroke and was taken as part of a larger randomized controlled study. Number of Subjects: Six individuals with stroke were trained to actively support their arm while reaching to various outward targets over a period of eight weeks. Materials/Methods: The intervention was progressed by increasing the level of required active limb support or gravitational loading experienced by the participant during reaching repetitions as performance improved. Functional work area was evaluated pre-and post-intervention for ten different support levels. Pre- and post-intervention clinical assessments were also taken by a blinded physical therapist as secondary outcomes. Results: Consistent with our previous work, there was a significant effect of limb support level such that as subjects were required to support up to and beyond the weight of their limb, there was a concurrent reduction in available work area. Notably, there was a significant effect of session on work area. Following the intervention, work area significantly increased for all limb support levels. There were also related improvements in the clinical assessment battery. Conclusions: This preliminary data suggests that specifically targeting the abnormal joint torque coupling impairment is an effective strategy for improving reaching work area following hemiparetic stroke. Clinical Relevance: Following the completion of this study physical therapists will have new evidence supporting the application of an impairment-targeted intervention for individuals with chronic and severe hemiparetic stroke.

Arm Training Induced Brain Plasticity in Stroke Studied with Serial Positron Emission Tomography

We used serial positron emission tomography (PET) to study training-induced brain plasticity after severe hemiparetic stroke. Ten patients were randomized to either task-oriented arm training or to a control group and scanned before and after 22.6 ± 1.6 days of treatment using passive movements as an activation paradigm. Increases of regional cerebral blood flow (rCBF) were assessed using statistical parametric mapping (SPM99). Before treatment, all stroke patients revealed bilateral activation of the inferior parietal cortex (IPC). After task-oriented arm training, activation was found bilaterally in IPC and premotor cortex, but also in the contralateral sensorimotor cortex (SMC). The control group only showed weak activation of the ipsilateral IPC. After treatment, the training group revealed relatively more activation bilaterally in IPC, premotor areas, and in the contralateral SMC. Five normal subjects showed no statistical significant differences between two separate PET studies. In this group of patients, task-oriented arm training induced functional brain reorganization in bilateral sensory and motor systems.