The aim of this study was to examine the effect of the side of brain lesion on the ipsilesional hand function of stroke survivors.
The aim of this study was to examine the effect of the side of brain lesion on the ipsilesional hand function of stroke survivors.
Twenty-four chronic stroke survivors, equally allocated in 2 groups according to the side of brain lesion (right or left), and 12 sex- and age-matched healthy controls performed the Jebsen-Taylor Hand Function Test (JTHFT), the Nine-Hole Peg Test (9HPT), the maximum power grip strength (PwGSmax) test, and the maximum pinch grip strength (PnGSmax) test. Only the ipsilesional hand of the stroke survivors and both hands (left and right) of the controls were assessed.
PwGS max and PnGS max were similar among all tested groups. Performances in JTHFT and 9HPT were affected by the brain injury. Individuals with left brain damage showed better performance in 9HPT than individuals with right brain damage, but performance in JTHFT was similar.
Individuals after a brain injury have the capacity to produce maximum strength preserved when using their ipsilesional hand. However, the dexterity of their hands and digits is affected, in particular for stroke individuals with right brain lesion.
We aimed to kinematically validate that the time to perform the Finger-to-Nose Test (FNT) assesses coordination by determining its construct, convergent and discriminant validity.
Experimental, criterion standard study. Both clinical and experimental evaluations were done at a research facility in a rehabilitation hospital. Forty individuals (20 individuals with chronic stroke and 20 healthy, age- and gender-matched individuals) participated.. Both groups performed two blocks of 10 to-and-fro pointing movements (non-dominant/affected arm) between a sagittal target and the nose (ReachIn, ReachOut) at a self-paced speed. Time to perform the test was the main outcome. Kinematics (Optotrak, 100Hz) and clinical impairment/activity levels were evaluated. Spatiotemporal coordination was assessed with slope (IJC) and cross-correlation (LAG) between elbow and shoulder movements.
Compared to controls, individuals with stroke (Fugl-Meyer Assessment, FMA-UE: 51.9 ± 13.2; Box & Blocks, BBT: 72.1 ± 26.9%) made more curved endpoint trajectories using less shoulder horizontal-abduction. For construct validity, shoulder range (β = 0.127), LAG (β = 0.855) and IJC (β = −0.191) explained 82% of FNT-time variance for ReachIn and LAG (β = 0.971) explained 94% for ReachOut in patients with stroke. In contrast, only LAG explained 62% (β = 0.790) and 79% (β = 0.889) of variance for ReachIn and ReachOut respectively in controls. For convergent validity, FNT-time correlated with FMA-UE (r = −0.67, p < 0.01), FMA-Arm (r = −0.60, p = 0.005), biceps spasticity (r = 0.39, p < 0.05) and BBT (r = −0.56, p < 0.01). A cut-off time of 10.6 s discriminated between mild and moderate-to-severe impairment (discriminant validity). Each additional second represented 42% odds increase of greater impairment.
For this version of the FNT, the time to perform the test showed construct, convergent and discriminant validity to measure UL coordination in stroke.
Upper-limb (UL) coordination deficits are commonly observed in neurological patients (e.g., cerebellar ataxia, stroke, etc.). In healthy subjects, goal-directed movement requires synchronized interaction (coordination) between multiple effectors [1, 2, 3]. Characterizing UL coordination, however, is challenging for clinicians and researchers because of lack of consensus regarding its definition (e.g., see [4, 5, 6, 7]). Nevertheless, definitions usually describe coordinated movement as involving specific patterns of temporal (timing between joints) and spatial (joint movement pattern) variability [1, 2, 8]. However, trajectory formation differs for reaches made in a body-centered frame of reference (egocentric) compared to those relying on mapping of extrinsic space and visuo-motor transformations [9, 10] made away from the body (exocentric). Thus, coordination can be defined as the skill of adjusting temporal and spatial aspects of joint rotations according to the task .
Damage to descending pathways due to stroke can lead to movement deficits defined at two levels. At the end-effector level (e.g. hand), variables describe movement performance (time, straightness, smoothness, precision), whereas at the interjoint level, variables describe movement quality (joint ranges of motion, interjoint coordination) . These variables may be affected differently for egocentric and exocentric movements.
Although it is widely recognized that training can improve performance of functional tasks even years after a stroke , a valid tool for the measurement of coordination has not yet been established. In healthy individuals, coordinated movements are described in terms of spatial variables, related to the positions of different joints or body segments in space and/or temporal variables, related to the timing between movements of joints/segments during the task . Consideration of task specificity is important in characterizing coordination. In addition, movement may be affected by abnormal stereotypical UL movement synergies and concomitant reduction in kinematic redundancy [10, 14] as well as deficits reducing both movement performance and quality [15, 16].
In clinical practice, coordination is assumed to be measured by the time to perform alternating movements with different end effectors (e.g., supination/pronation of the forearm, sliding the heel up and down the anterior aspect of the shin). Another task commonly used to assess coordination is the Finger-to-Nose test (FNT) [17, 18]. In the standard neurological exam , the individual alternately touches their nose and the evaluator’s stationary or moving finger while lying supine, sitting or standing. In the Fugl-Meyer UL Assessment (FMA-UL) , the FNT is objectively measured as the difference in time to alternately touch the knee and nose five times between the more- and less-affected arm on a 0 to 2 point scale. Aside from FNT-time, two other features of endpoint performance, arm trajectory straightness/smoothness (tremor) and precision (dysmetria), are estimated qualitatively  for a total of six points.
However, the construct validity of FNT-time as an UL coordination measure in individuals with stroke has not been established using detailed kinematic assessment, where construct validity is defined as the degree to which experimentally-determined and theoretical definitions match . For clinicians to use FNT as part of the UL assessment, this assumption must be verified along with its convergent and discriminant validity.
The study objectives were to determine construct, convergent and discriminant validity of FNT-time to measure UL coordination in individuals with chronic stroke using kinematic analysis. We characterized movement parameters during performance of FNT between healthy and stroke subjects. We also related FNT outcomes (time, trajectory straightness, precision) to UL impairment severity and activity limitations. We hypothesized that FNT-time would 1) be related to interjoint coordination measures (construct validity); 2) be correlated with other measures of UL impairment and/or activity limitations (convergent validity); and 3) discriminate between levels of UL impairment (discriminant validity). Preliminary data have appeared in abstract form .
Powered robotic exoskeletons are a potential intervention for gait rehabilitation in stroke to enable repetitive walking practice to maximize neural recovery. As this is a relatively new technology for stroke, a scoping review can help guide current research and propose recommendations for advancing the research development.
The aim of this scoping review was to map the current literature surrounding the use of robotic exoskeletons for gait rehabilitation in adults post-stroke. Five databases (Pubmed, OVID MEDLINE, CINAHL, Embase, Cochrane Central Register of Clinical Trials) were searched for articles from inception to October 2015. Reference lists of included articles were reviewed to identify additional studies. Articles were included if they utilized a robotic exoskeleton as a gait training intervention for adult stroke survivors and reported walking outcome measures.
Of 441 records identified, 11 studies, all published within the last five years, involving 216 participants met the inclusion criteria. The study designs ranged from pre-post clinical studies (n = 7) to controlled trials (n = 4); five of the studies utilized a robotic exoskeleton device unilaterally, while six used a bilateral design. Participants ranged from sub-acute (<7 weeks) to chronic (>6 months) stroke. Training periods ranged from single-session to 8-week interventions. Main walking outcome measures were gait speed, Timed Up and Go, 6-min Walk Test, and the Functional Ambulation Category.
Meaningful improvement with exoskeleton-based gait training was more apparent in sub-acute stroke compared to chronic stroke. Two of the four controlled trials showed no greater improvement in any walking outcomes compared to a control group in chronic stroke.
In conclusion, clinical trials demonstrate that powered robotic exoskeletons can be used safely as a gait training intervention for stroke. Preliminary findings suggest that exoskeletal gait training is equivalent to traditional therapy for chronic stroke patients, while sub-acute patients may experience added benefit from exoskeletal gait training. Efforts should be invested in designing rigorous, appropriately powered controlled trials before powered exoskeletons can be translated into a clinical tool for gait rehabilitation post-stroke.
Stroke is a leading cause of acquired disability in the world, with increasing survival rates as medical care and treatment techniques improve . This equates to an increasing population with stroke-related disability [1, 2], who experience limitations in communication, activities of daily living, and mobility . A majority of this population ranks recovering the ability to walk or improving walking ability among their top rehabilitation goals [4, 5]; furthermore, the ability to walk is a determining factor as to whether an individual is able to return home after their stroke . However, 30 – 40 % of stroke survivors have limited or no walking ability even after rehabilitation [7, 8] and so there is an ongoing need to advance the efficacy of gait rehabilitation for stroke survivors.
Powered robotic exoskeletons are a recently developed technology that allows individuals with lower extremity weakness to walk . These wearable robots strap to the legs and have electrically actuated motors that control joint motion to automate overground walking. Powered exoskeletons were originally designed to be used as an assistive device to allow individuals with complete spinal cord injury to walk . However, because they allow for walking without overhead body weight support or a treadmill, they have gained attention as an alternate intervention for gait rehabilitation in other populations such as stroke where repetitive gait training has been shown to yield improvements in walking function [11, 12]. Several powered exoskeletons are already commercially available, such as the Ekso (Ekso Bionics, USA), Rewalk (Rewalk Robotics, Israel), and Indego (Parker Hannifin, USA) exoskeletons, with more being developed.
There have been many forms of gait retraining proposed for stroke survivors. Conventional physical therapy gait rehabilitation leads to improvements in speed and endurance , particularly when conducted early post-stroke . However, conventional gait retraining using hands-on assistance can be taxing on therapists; the number of steps actually taken in a session reflects this and has been shown to be low in sub-acute hospital rehabilitation . Many of the proposed technology-based gait intervention strategies have focused on reducing the physical strain to therapists while increasing the amount of walking repetition that individuals undergo. For example, body weight-supported treadmill training (BWSTT) allows therapists to manually move the hemiparetic limb in a cyclical motion while the patient’s trunk and weight are partially supported by an overhead harness system; this has shown improvements in stroke survivors’ gait speed and endurance compared to conventional gait training , yet still places a high physical demand on therapists. Advances in technology have led to treadmill-based robotics, such as the Lokomat (Hocoma, Switzerland), LOPES (University of Twente, Netherlands), and G-EO (Reha-Technology, Switzerland), which have bracing that attaches to the patient’s legs to take them through a walking motion on the treadmill. The appeal of this technology is that it can provide substantially higher repetitions for walking practice than BWSTT without placing strain on therapists; however, there is conflicting evidence regarding the efficacy of treadmill-based robotics for gait training compared to conventional therapy or BWSTT. Some studies have shown that treadmill robotics improve walking independence in stroke [17, 18] but do not improve speed or endurance [18, 19]. There has been some sentiment that such technology has not lived up to the expectations originally predicted based on theory and practice . One argument is that these treadmill robotics with a pre-set belt speed, combined with body weight support, create an environment where the patient has less control over the initiation of each step ; another argument against treadmill-based gait training is the lack of variability in visuospatial flow, which is an essential challenge of overground walking . Powered robotic exoskeletons, though similar in structure to treadmill-based robotics, differ in that they require active participation from the user for both swing initiation and foot placement; for example, some exoskeletons have control strategies which will only assist the stepping motion when it detects adequate lateral weight-shifting . Furthermore, because the powered exoskeletons are used for overground walking, it requires the user to be responsible for maintaining trunk and balance control, as well as navigating their path over varying surfaces.
While these powered exoskeletons hold promise, the literature surrounding their use for gait training is only just beginning to gather, with the majority focusing on spinal cord injury [22, 23, 24]. Several [25, 26, 27] systematic reviews have shown safe usage, positive effects as an assistive device, and exercise benefits for individuals with spinal cord injury. Only one systematic review  specifically focusing on powered exoskeletons has included studies involving stroke participants, though studies in spinal cord injury and other conditions were also included. This review focused exclusively on the Hybrid Assistive Limb (HAL) exoskeleton (Cyberdyne, Japan), (which currently is not approved for clinical use outside of Japan), and found beneficial effects on gait function and walking independence; however, the results were combined generally across all included patient populations and not specifically for stroke.
Given that this is a relatively new intervention for stroke, the objective of this scoping review was to map the current literature surrounding the use of powered robotic exoskeletons for gait rehabilitation in post-stroke individuals and to identify gaps in the research. The second objective of this scoping review was to preliminarily explore the efficacy of exoskeleton-based gait rehabilitation in stroke. As this is a relatively new technology for stroke, a scoping review can help guide current research and propose recommendations for advancing the technology.
A cerebrovascular accident (CVA) may affect basic motor functions, including spasticity that may be present in the upper extremity and/or the lower extremity, post-stroke.
Spasticity causes pain, muscle force reduction, and decreases the time to onset of muscle fatigue. Several therapeutic resources have been employed to treat CVA to promote functional recovery. The clinical use of low-level laser therapy (LLLT) for rehabilitation of muscular disorders has provided better muscle responses.
Thus, the aim of this study was to evaluate the effect of the application of LLLT in spastic muscles in patients with spasticity post-CVA. A double-blind clinical trial was conducted with 15 volunteer stroke patients who presented with post-stroke spasticity. Both males and females were treated; the average age was 51.5 ± 11.8 years old; the participants entered the study ranging from 11 to 48 months post-stroke onset. The patients participated in three consecutive phases (control, placebo, and real LLLT), in which all tests of isometric endurance of their hemiparetic lower limb were performed. LLLT (diode laser, 100 mW 808 nm, beam spot area 0.0314 cm2, 127.39 J/cm2/point, 40 s) was applied before isometric endurance. After the real LLLT intervention, we observed significant reduction in the visual analogue scale for pain intensity (p = 0.0038), increased time to onset of muscle fatigue (p = 0.0063), and increased torque peak (p = 0.0076), but no significant change in the root mean square (RMS) value (electric signal in the motor unit during contraction, as obtained with surface electromyography).
Our results suggest that the application of LLLT may contribute to increased recruitment of muscle fibers and, hence, to increase the onset time of the spastic muscle fatigue, reducing pain intensity in stroke patients with spasticity, as has been observed in healthy subjects and athletes.
In well-recovered stroke patients with preserved hand movement, motor dysfunction relates to interhemispheric and intracortical inhibition in affected hand muscles. In less fully recovered patients unable to move their hand, the neural substrates of recovered arm movements, crucial for performance of daily living tasks, are not well understood.
Here, we evaluated interhemispheric and intracortical inhibition in paretic arm muscles of patients with no recovery of hand movement (n = 16, upper extremity Fugl-Meyer Assessment = 27.0 ± 8.6). We recorded silent periods (contralateral and ipsilateral) induced by transcranial magnetic stimulation during voluntary isometric contraction of the paretic biceps and triceps brachii muscles (correlates of intracortical and interhemispheric inhibition, respectively) and investigated links between the silent periods and motor recovery, an issue that has not been previously explored.
We report that interhemispheric inhibition, stronger in the paretic triceps than biceps brachii muscles, significantly correlated with the magnitude of residual impairment (lower Fugl-Meyer scores). In contrast, intracortical inhibition in the paretic biceps brachii, but not in the triceps, correlated positively with motor recovery (Fugl-Meyer scores) and negatively with spasticity (lower Modified Ashworth scores).
Our results suggest that interhemispheric inhibition and intracortical inhibition of paretic upper arm muscles relate to motor recovery in different ways. While interhemispheric inhibition may contribute to poorer recovery, muscle-specific intracortical inhibition may relate to successful motor recovery and lesser spasticity.
Rehabilitation interventions involving virtual reality (VR) technology have been developed for the promotion of functional independence post stroke. A scoping review was performed to examine the efficacy of VR-based interventions on balance and mobility disorders post stroke.
Twenty-four articles in the English language examining VR game-based interventions and outcomes directed at balance and mobility disorders were included. Various VR systems (customized and commercially available) were used as rehabilitation tools. Outcome measures included laboratory and clinical measures of balance and gait. Outcome measures of dynamic balance showed significant improvements following VR-based interventions as compared to other interventions. Further, it was observed that VR-based intervention may have favorable effects in improving walking speed and the ability to deal with environmental challenges, which may also facilitate independent community ambulation.
VR-based therapy thus has the potential to be a useful tool for balance and gait training for stroke rehabilitation. Utilization of motor learning principles related to task-related training may have been an important factor leading to positive results. Other principles such as repetition, feedback etc. were used in studies but were not explored explicitly and may need to be investigated to further improve the strength of results.
Lastly, robust study designs with appropriate attention towards the intensity and dose-response aspects of VR training, clear study objectives and suitable outcomes would further aid in determining evidence-based efficacy for VR game-based interventions in the future.
Objective. This study examines performance of Wolf Motor Function Test (WMFT) tasks in terms of the ability of EXCITE trial participants (who had suffered a stroke 3-9 months before recruitment) to complete the task within the timed interval. Methods.Data were collected from participants who received constraint-induced movement therapy (CIMT) 3 to 9 months poststroke (CIMT-I, n = 106) or 15 to 21 months poststroke (CIMT-D, n = 116). Performance on the 15 timed WMFT tasks was converted into binary values, and changes in completion of the tasks were analyzed with generalized estimating equation methods, under the assumption of a binomial or Poisson process for completion. Results. During CIMT, the CIMT-I group showed significant within-group improvements in 3 fine-movement tasks and in total noncompleted tasks (noncompletes), whereas the CIMT-D group did not (P ≤ .0036). CIMT-I improvement was significantly greater than CIMT-D improvement for the lifting pencil task and total noncompletes. During the year following CIMT, neither group showed significant changes in completion of WMFT tasks. Over all time intervals, only the CIMT-I group displayed significant improvement in several tasks and total noncompletes. Between groups, there were significant and almost-significant differences between the improvements of the 2 groups in 3 tasks requiring fine distal movement. Conclusion. Receiving CIMT earlier appears to improve reacquisition and retention of WMFT tasks, especially those requiring fine motor skills. Combined with earlier findings, these results indicate that improvements in existing motor abilities are possible with both immediate and delayed CIMT, but early CIMT is necessary for significant reacquisition of tasks.
via The EXCITE Trial.
…The objectives of this commentary are to (1) to encourage practitioners to reconsider the notion of the motor recovery plateau, (2) to reconsider chronic CVA patients’ ability to recover motor function, and (3) to use different modalities when accommodation is exhibited…