Posts Tagged chronic stroke

[Abstract] Computer-aided prediction of extent of motor recovery following constraint-induced movement therapy in chronic stroke

Abstract

Constraint-induced movement therapy (CI therapy) is a well-researched intervention for treatment of upper limb function. Overall, CI therapy yields clinically meaningful improvements in speed of task completion and greatly increases use of the more affected upper extremity for daily activities. However, individual improvements vary widely. It has been suggested that intrinsic feedback from somatosensation may influence motor recovery from CI therapy. To test this hypothesis, an enhanced probabilistic neural network (EPNN) prognostic computational model was developed to identify which baseline characteristics predict extent of motor recovery, as measured by the Wolf Motor Function Test (WMFT). Individual characteristics examined were: proprioceptive function via the brief kinesthesia test, tactile sensation via the Semmes-Weinstein touch monofilaments, motor performance captured via the 15 timed items of the Wolf Motor Function Test, stroke affected side. A highly accurate predictive classification was achieved (100% accuracy of EPNN based on available data), but facets of motor functioning alone were sufficient to predict outcome. Somatosensation, as quantified here, did not play a large role in determining the effectiveness of CI therapy.

Source: Computer-aided prediction of extent of motor recovery following constraint-induced movement therapy in chronic stroke – ScienceDirect

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[Abstract] A soft robotic supernumerary finger and a wearable cutaneous finger interface to compensate the missing grasping capabilities in chronic stroke patients

Abstract:

Stroke survivors who experience severe hemipare-sis often cannot completely recover the use of their hand and arm. Many of the rehabilitation devices currently available are designed to increase the functional recovery right after the stroke when, in some cases, biological restoring and plastic reorganization of the central nervous system can take place. However, this is not always the case. Even after extensive therapeutic interventions, the probability of regaining functional use of the impaired hand is low. In this respect, we present a novel robotic system composed of a supernumerary robotic finger and a wearable cutaneous finger interface. The supernumerary finger is used to help grasping objects while the wearable interface provides information about the forces exerted by the robotic finger on the object being held. We carried out two experiments, enrolling 16 healthy subjects and 2 chronic stroke patients. Results showed that using the supernumerary finger greatly improved the grasping capabilities of the subjects. Moreover, providing cutaneous feedback significantly improved the performance of the considered task and was preferred by all subjects.

Source: A soft robotic supernumerary finger and a wearable cutaneous finger interface to compensate the missing grasping capabilities in chronic stroke patients – IEEE Xplore Document

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[Abstract] A Longitudinal EMG Study of Complex Upper-limb Movements in Post-stroke Therapy. 1: Heterogeneous EMG Changes despite Consistent Improvements in Clinical Assessments

Post-stroke weakness on the more-affected side may arise from reduced corticospinal drive, disuse muscle atrophy, spasticity, and abnormal co-ordination. This study investigated changes in muscle activation patterns to understand therapy-induced improvements in motor-function in chronic stroke compared to clinical assessments, and to identify the effect of motor-function level on muscle activation changes.

Electromyography (EMG) was recorded from 5 upper-limb muscles on the more-affected side of 24 patients during early- and late-therapy sessions of an intensive 14-day program of Wii-based Movement Therapy, and for a subset of 13 patients at 6-month follow-up. Patients were classified according to residual voluntary motor capacity with low, moderate or high motor-function. The area under the curve was calculated from EMG amplitude and movement duration. Clinical assessments of upper-limb motor-function pre- and post-therapy included the Wolf Motor Function Test, Fugl-Meyer Assessment and Motor Activity Log Quality of Movement scale.

Clinical assessments improved over time (p<0.01) with an effect of motor-function level (p<0.001). The pattern of EMG change by late-therapy was complex and variable, with differences between patients with low compared to moderate or high motor-function. The area under the curve (p=0.028) and peak amplitude (p=0.043) during Wii-tennis backhand increased for patients with low motor-function whereas EMG decreased for patients with moderate and high motor-function. The reductions included: movement duration during Wii-golf (p=0.048, moderate; p=0.026, high), and Wii-tennis backhand (p=0.046, moderate; p=0.023, high) and forehand (p=0.009, high); and the area under the curve during Wii-golf (p=0.018, moderate) and Wii-baseball (p=0.036, moderate). For the pooled data over time there was an effect of motor-function (p=0.016) and an interaction between time and motor-function (p=0.009) for Wii-golf movement duration. Wii-baseball movement duration decreased as a function of time (p=0.022). There was an effect on Wii-tennis forehand duration for time (p=0.002) and interaction of time and motor-function (p=0.005); and an effect of motor-function level on the area under the curve (p=0.034) for Wii-golf.

This study demonstrated different patterns of EMG changes according to residual voluntary motor-function levels despite heterogeneity within each level that was not evident following clinical assessments alone. Thus, rehabilitation efficacy might be underestimated by analyses of pooled data.

Source: Frontiers | A Longitudinal EMG Study of Complex Upper-limb Movements in Post-stroke Therapy. 1: Heterogeneous EMG Changes despite Consistent Improvements in Clinical Assessments | Neurology

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[Abstract] Gross Motor AbiLity predictS Response to upper extremity rehabilitation in chronic stroke

Abstract

The majority of rehabilitation research focuses on the comparative effectiveness of different interventions in groups of patients, while much less is currently known regarding individual factors that predict response to rehabilitation. In a recent article, authors presented a prognostic model to identify the sensorimotor characteristics predictive of the extent of motor recovery after Constraint-Induced Movement (CI) therapy amongst individuals with chronic mild-to-moderate motor deficit using the enhanced probabilistic neural network (EPNN). This follow-up paper examines which participant characteristics are robust predictors of rehabilitation response irrespective of the training modality. To accomplish this, EPNN was first applied to predict treatment response amongst individuals who received a virtual-reality gaming intervention (utilizing the same enrollment criteria as the prior study). The combinations of predictors that yield high predictive validity for both therapies, using their respective datasets, were then identified. High predictive classification accuracy was achieved for both the gaming (94.7%) and combined datasets (94.5%). Though CI therapy employed primarily fine-motor training tasks and the gaming intervention emphasized gross-motor practice, larger improvements in gross motor function were observed within both datasets. Poorer gross motor ability at pre-treatment predicted better rehabilitation response in both the gaming and combined datasets. The conclusion of this research is that for individuals with chronic mild-to-moderate upper extremity hemiparesis, residual deficits in gross motor function are highly responsive to motor restorative interventions, irrespective of the modality of training.

Source: Gross Motor AbiLity predictS Response to upper extremity rehabilitation in chronic stroke – ScienceDirect

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[Abstract] A Randomized Trial on the Effects of Attentional Focus on Motor Training of the Upper Extremity Using Robotics with Individuals after Chronic Stroke 

 

Highlights

  • Individuals with moderate-to-severe arm impairment after stroke improved motor control after engaging in high-repetition training
  • There were no differences between external focus or internal focus of attention on retention of motor skills after four weeks of arm training for individuals with stroke
  • Individuals with moderate-to-severe arm impairment may not experience the advantages of an external focus during motor training found in healthy individuals
  • Attentional focus is most likely not an active ingredient for retention of trained motor skills for individuals with moderate-to-severe arm impairment

Abstract

Objective

To compare the long-term effects of external focus (EF) versus internal focus (IF) of attention after 4-weeks of arm training. Design: Randomized, repeated measure, mixed ANOVA.

Setting

Outpatient clinic.

Participants

33 individuals with stroke and moderate-to-severe arm impairment living in the community (3 withdrawals).

Interventions

4-week arm training protocol on the InMotion ARM robot (12 sessions).

Main Outcome Measures

Joint independence, Fugl-Meyer Assessment, and Wolf Motor Function Test measured at baseline, discharge, and 4-week follow-up.

Results

There were no between-group effects for attentional focus. Participants in both groups improved significantly on all outcome measures from baseline to discharge and maintained those changes at 4-week follow-up regardless of group assignment [Jt indep-EF, F(1.6, 45.4) = 17.74, p<.0005, partial η2=.39; Jt indep-IF, F(2, 56)= 18.66, p<.0005, partial η2=.40; FMA, F(2, 56) = 27.83, p<.0005, partial η2=.50 ; WMFT, F(2, 56) =14.05, p<.0005, partial η2=.35].

Conclusion

There were no differences in retention of motor skills between EF and IF participants four weeks after arm training, suggesting that individuals with moderate-to-severe arm impairment may not experience the advantages of an EF found in healthy individuals. Attentional focus is most likely not an active ingredient for retention of trained motor skills for individuals with moderate-to-severe arm impairment, whereas dosage and intensity of practice appear to be pivotal. Future studies should investigate the long-term effects of attentional focus for individuals with mild arm impairment.

Source: A Randomized Trial on the Effects of Attentional Focus on Motor Training of the Upper Extremity Using Robotics with Individuals after Chronic Stroke – Archives of Physical Medicine and Rehabilitation

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[Abstract] The Effect of Modified Constraint-Induced Movement Therapy on Spasticity and Motor Function of the Affected Arm in Patients with Chronic Stroke

Purpose: The purpose of this study was to explore the effect of modified constraint-induced movement therapy (CIMT) in a real-world clinical setting on spasticity and functional use of the affected arm and hand in patients with spastic chronic hemiplegia.

Method: A prospective consecutive quasi-experimental study design was used. Twenty patients with spastic hemiplegia (aged 22–67 years) were tested before and after 2-week modified CIMT in an outpatient rehabilitation clinic and at 6 months. The Modified Ashworth Scale (MAS), active range of motion (AROM), grip strength, Motor Activity Log (MAL), Sollerman hand function test, and Box and Block Test (BBT) were used as outcome measures.

Results: Reductions (p<0.05–0.001) in spasticity (MAS) were seen both after the 2-week training period and at 6-month follow-up. Improvements were also seen in AROM (median change of elbow extension 5°, dorsiflexion of hand 10°), grip strength (20 Newton), and functional use after the 2-week training period (MAL: 1 point; Sollerman test: 8 points; BBT: 4 blocks). The improvements persisted at 6-month follow-up, except for scores on the Sollerman hand function test, which improved further.

Conclusion: Our study suggests that modified CIMT in an outpatient clinic may reduce spasticity and increase functional use of the affected arm in spastic chronic hemiplegia, with improvements persisting at 6 months.

Source: The Effect of Modified Constraint-Induced Movement Therapy on Spasticity and Motor Function of the Affected Arm in Patients with Chronic Stroke | Physiotherapy Canada

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[ARTICLE] Upper Extremity Motor Impairments and Microstructural Changes in Bulbospinal Pathways in Chronic Hemiparetic Stroke – Full Text

Following hemiparetic stroke, precise, individuated control of single joints is often replaced by highly stereotyped patterns of multi-joint movement, or abnormal limb synergies, which can negatively impact functional use of the paretic arm. One hypothesis for the expression of these synergies is an increased dependence on bulbospinal pathways such as the rubrospinal (RubST) tract and especially the reticulospinal (RetST) tracts, which co-activate multiple muscles of the shoulder, elbow, wrist, and fingers. Despite indirect evidence supporting this hypothesis in humans poststroke, it still remains unclear whether it is correct. Therefore, we used high-resolution diffusion tensor imaging (DTI) to quantify white matter microstructure in relation to severity of arm synergy and hand-related motor impairments. DTI was performed on 19 moderately to severely impaired chronic stroke individuals and 15 healthy, age-matched controls. In stroke individuals, compared to controls, there was significantly decreased fractional anisotropy (FA) and significantly increased axial and radial diffusivity in bilateral corona radiata and body of the corpus callosum. Furthermore, poststroke, the contralesional (CL) RetST FA correlated significantly with both upper extremity (UE) synergy severity (r = −0.606, p = 0.003) and hand impairment (r = −0.609, p = 0.003). FA in the ipsilesional RubST significantly correlated with hand impairment severity (r = −0.590, p = 0.004). For the first time, we separately evaluate RetST and RubST microstructure in chronic stroke individuals with UE motor impairment. We demonstrate that individuals with the greatest UE synergy severity and hand impairments poststroke have the highest FA in the CL RetST a pattern consistent with increased myelination and suggestive of neuroplastic reorganization. Since the RetST pathway microstructure, in particular, is sensitive to abnormal joint coupling and hand-related motor impairment in chronic stroke, it could help test the effects of specific, and novel, anti-synergy neurorehabilitation interventions for recovery from hemiparesis.

Introduction

Approximately 85% of stroke survivors experience significant motor impairment in the contralesional (CL) arm (1), which can include a loss of independent joint control (2, 3), weakness (4), and spasticity (5). After stroke, precise, individuated control of single joints is often replaced by highly stereotyped patterns of multi-joint movement caused by abnormal muscle co-activation patterns (6). The most prevalent of these patterns is the flexion synergy, which is characterized by an abnormal coupling of shoulder abduction and elbow, wrist, and finger flexion (7, 8). This impairment has a negative impact on reaching ability (9) and hand function (3, 10), both critical components of functional use of the arm during activities of daily living. Despite the debilitating nature of this motor impairment, the underlying neuropathophysiology is not fully understood.

One hypothesis for why the flexion synergy emerges is that following a reduction of corticofugal input from the lesioned hemisphere, there is an increased dependence on CL motor cortex and bulbospinal pathways, such as reticulospinal (RetST) and rubrospinal (RubST) tracts. Therefore, in the present study, we quantify microstructural properties in white matter of both the brain and the brainstem, focusing primarily on corticoreticulospinal and corticorubrospinal systems. We evaluate whether these microstructural properties increase in integrity in relation to arm synergy and hand impairment severity, which could be indicative of increased use.

Although the RetST was previously believed to be predominantly involved in gross movements, such as locomotion (11, 12) and posture (13, 14), recent work in primates suggests the RetST also influences the motor neurons that control forearm and intrinsic hand muscles (15). In the non-human primate, stimulation of the RetST produces ipsilateral wrist flexor, elbow flexor, and shoulder abductor activation (16), mirroring the flexion synergy pattern observed in humans poststroke. Furthermore, stimulating the RetST after a corticospinal tract (CST) lesion elicits increased excitatory post-synaptic potentials in motoneurons innervating the forearm flexor and intrinsic hand muscles (17). This evidence makes the contralesional corticoreticulospinal system a compelling candidate for underlying abnormal joint coupling in humans with hemiparetic stroke.

In the non-human primate, the RubST also contributes to reaching and grasping movements (18) and has been shown to be important in recovery of hand function after CST damage (19, 20). One study showed that increased white matter integrity in bilateral red nucleus (RN) correlated with worse clinical outcomes in humans with chronic stroke (21); however, the RubST has been reported as relatively insignificant in humans (22, 23). The evidence for whether the RetST and the RubST contribute to abnormal joint coupling and hand impairment in humans poststroke still remains indirect and inconclusive.

We used high-resolution diffusion tensor imaging (DTI) (24) tract-based spatial statistics (TBSS) (25) to perform a voxel-wise comparison of white matter microstructure between stroke and control individuals. We analyzed fractional anisotropy (FA), a measurement typically associated with tract integrity, as well as axial diffusivity (AD) and radial diffusivity (RD), which represent diffusion parallel and perpendicular to the principle direction of diffusion, respectively. Because previous studies have reported altered diffusion properties in lesioned tissue (2628), we excluded potential lesion-compromised voxels from our TBSS analysis to assess changes in normal-appearing white matter. We used the TBSS-derived white matter skeleton to investigate whether microstructural tissue properties within specific regions of the brainstem (CST, RetST, RubST) and subcortical white matter within CL motor areas [primary motor area (M1), premotor area (PM), supplementary motor area (SMA), body of the corpus callosum] are sensitive to upper extremity (UE) motor impairment in chronic stroke individuals.

We evaluated UE motor impairment using the Fugl-Meyer Assessment (FMA), a stroke-specific, performance-based motor impairment index, which measures impairments, such as loss of independent joint function, stretch reflex hyper-excitability, and altered sensation (29). It is one of the most widely used clinical scales of motor impairment poststroke (30). While previous studies have looked at diffusion MRI metrics in relation to the entire FMA score (31, 32), we used only the UE measurements of arm synergies and hand function to determine whether microstructural properties in specific white matter regions of interest (ROIs) were correlated.

In the present study, we hypothesized that microstructural integrity in specific regions of the extrapyramidal brainstem would be increased in chronic stroke in a manner sensitive to synergy and hand-related impairment severity. We demonstrate a significant decrease in FA in bilateral corona radiata and body of the corpus callosum in chronic stroke when compared to controls; however, within stroke subjects, specific brainstem regions show the highest FA in individuals with the most synergy-driven arm and hand impairment. More precisely, we describe the relation between CL RetST integrity and both expression of synergy and hand impairment and between ipsilesional (IL) RubST integrity and hand impairment in chronic hemiparetic stroke individuals.[…]

Continue —> Frontiers | Upper Extremity Motor Impairments and Microstructural Changes in Bulbospinal Pathways in Chronic Hemiparetic Stroke | Neurology

Figure 1. Region of interest masks in Montreal Neurological Institute’s space. (A) Primary motor area (red), supplementary motor area (green), premotor area (blue), (B) body of the corpus callosum (light blue), (C) horizontal midbrain cross-section showing cerebral peduncle (CP) portion of the corticospinal tract (yellow) and red nucleus (RN) (red), (D) horizontal pontine cross-section showing reticular formation (RF) (green), and (E) sagittal brainstem showing RF including reticulospinal (green) and RN including rubrospinal tracts (red).

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[Abstract] Feasibility and efficacy of wearable devices for upper limb rehabilitation in patients with chronic stroke: a randomized controlled pilot study

Wearable devices based on inertial measurement units through wireless sensor networks have many applications such as real-time motion monitoring and functional outcome assessment of stroke rehabilitation. However, additional investigations are warranted to validate their clinical value, particularly in detecting the synergy patterns of movements after stroke.To explore the feasibility and efficacy of wearable devices for upper limb rehabilitation in patients with chronic stroke and to compare the intervention effects (e.g., neurological recovery, active range of motion, and deviation angle) with those in a control group.A single-blind, randomized-controlled pilot study.Rehabilitation ward.A total of 18 patients with chronic stroke were randomly distributed into a device group and control group. Both groups received conventional rehabilitation; nevertheless, the device group was additionally subjected to 15 daily sessions at least three times a week for 5 weeks. The outcome measures included the upper extremity subscores of the Fugl-Meyer assessment, active range of motion, and deviation angle. These measurements were performed pre- and post-treatment.All five Fugl-Meyer assessment subscores improved in both the device and control groups after intervention; in particular, the “shoulder/elbow/forearm” subscore (p = 0.02, 0.03) and “total score” (p = 0.03, 0.03) substantially improved. The active range of motion of shoulder flexion and abduction substantially improved at pre-post treatment in both the device (p = 0.02, 0.03) and control (p = 0.02, 0.03) groups. The deviation angle of shoulder external rotation during shoulder abduction substantially improved in the device group (p = 0.02), but not in the control group.The designed wearable devices are practical and efficient for use in chronic patients with stroke.Wearable devices are expected to be useful for future internet-of-things rehabilitation clinical trials at home and in long-term care institutions.

Source: Feasibility and efficacy of wearable devices for upper limb rehabilitation in patients with… – Abstract – Europe PMC

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[Abstract] A Longitudinal EMG Study of Complex Upper-limb Movements in Post-stroke Therapy: 2 Changes in Co-ordinated Muscle Activation

Fine motor control is achieved through the co-ordinated activation of groups of muscles, or ‘muscle synergies’. Muscle synergies change after stroke as a consequence of the motor deficit. We investigated the pattern and longitudinal changes in upper-limb muscle synergies during therapy in a largely unconstrained movement in patients with a broad spectrum of post-stroke residual voluntary motor capacity.Electromyography (EMG) was recorded using wireless telemetry from 6 muscles acting on the more-affected upper body in 24 stroke patients at early- and late-therapy during formal Wii-based Movement Therapy sessions, and in a subset of 13 patients at 6-month follow-up. Patients were classified with low, moderate or high motor-function. The Wii-baseball swing was analysed using a non-negative matrix factorisation (NMF) algorithm to extract muscle synergies from EMG recordings based on the temporal activation of each synergy and the contribution of each muscle to a synergy. Motor-function was clinically assessed immediately pre- and post-therapy and at 6-month follow-up using the Wolf Motor Function Test, upper-limb motor Fugl-Meyer Assessment and Motor Activity Log Quality of Movement scale.Clinical assessments and game performance demonstrated improved motor-function for all patients at post-therapy (p0.05). NMF analysis revealed fewer muscle synergies (mean±SE) for patients with low motor-function (3.38±0.2) than those with high motor-function (4.00±0.3) at early-therapy (p=0…

Source: A Longitudinal EMG Study of Complex Upper-limb Movements in Post-stroke Therapy: 2 Changes in Co-ordinated Muscle Activation

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[ARTICLE] Functional Electrical Stimulation with Augmented Feedback Training Improves Gait and Functional Performance in Individuals with Chronic Stroke: A Randomized Controlled Trial – Full Text PDF

Abstract

Purpose: The purpose of this study was to compare the effects of the FES-gait with augmented feedback training to the FES alone on the gait and functional performance in individuals with chronic stroke.

Methods: This study used a pretest and posttest randomized control design. The subjects who signed the agreement were randomly divided into 12 experimental groups and 12 control groups. The experimental groups performed two types of augmented feedback training (knowledge of performance and knowledge of results) together with FES, and the control group performed FES on the TA and GM without augmented feedback and then walked for 30 minutes for 40 meters. Both the experimental groups and the control groups received training five times a week for four weeks.

Results: The groups that received the FES with augmented feedback training significantly showed a greater improvement in single limb support (SLS) and gait velocity than the groups that received FES alone. In addition, timed up and go (TUG) test and six minute walk test (6MWT) showed a significant improvement in the groups that received FES with augmented feedback compared to the groups that received FES alone.

Conclusion: Compared with the existing FES gait training, augmented feedback showed improvements in gait parameters, walking ability, and dynamic balance. The augmented feedback will be an important method that can provide motivation for motor learning to stroke patients.

Full Text PDF

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