Upper-limb Activity Research Articles

Outside the Laboratory Assessment of Upper Limb Laterality in Patients With Stroke: A Cross-Sectional Study.

The rehabilitation of upper limb sensorimotor performance after stroke requires the assessment of daily use, the identification of key levels of impairment, and monitoring the course of recovery. It needs to be answered, how laboratory-based assessments and everyday behavior are connected, which dimension of metrics, that is, volume, intensity, or quality, is most sensitive to reduced function, and what sensor, that is, gyroscope or accelerometer, is best suited to gather such data. Performance in laboratory-based sensorimotor tests, as well as smartwatch-derived kinematic data of everyday life relative upper limb activity, during 1 day of inpatient neurorehabilitation (Germany, 2022) of 50 patients with stroke, was cross-sectionally assessed and resulting laterality indices (performance ratios) between the limbs were analyzed using ANCOVAs and principal component analysis. Laboratory-based tests revealed the strongest laterality indices, followed by smartwatch-based (intensity>quality>volume) metrics. Angular velocity-based metrics revealed higher laterality indices than acceleration-based ones. Laterality indices were overall well associated; however, a principal component analysis suggested upper limb impairments to be unidimensional. Our findings suggest that the use of sensors can deliver valid information of stroke-related laterality. It appeared that commonly used metrics that estimate the volume of use (ie, energy expenditure) are not the most sensitive. Especially reached intensities could be well used for monitoring, because they are more dependent on the performance of the sensorimotor system and less on confounders like age. The unidimensionality of the upper limb laterality suggests that an impaired limb with reduced movement quality and the inability to reach higher intensities will be used less in everyday life, especially when it is the nondominant side.

Contralaterally controlled functional electrical stimulation video game therapy for hand rehabilitation after stroke: a randomized controlled trial

Purpose To estimate the effect of integrating custom-designed hand therapy video games (HTVG) with contralaterally controlled functional electrical stimulation (CCFES) therapy. Methods Fifty-two stroke survivors with chronic (>6 months) upper limb hemiplegia were randomized to 12 weeks of CCFES or CCFES + HTVG. Treatment involved self-administration of technology-mediated therapy at home plus therapist-administered CCFES-assisted task practice in the lab. Pre- and post-treatment assessments were made of hand dexterity, upper limb impairment and activity limitation, and cognitive function. Results No significant between-group differences were found on any outcome measure, and the average magnitudes of improvement within both groups were small. The incidence of technical problems with study devices at home was greater for the CCFES + HTVG group. This negatively affected adherence and may partially explain the absence of effect of HTVG. At end-of-treatment, large majorities of both treatment groups had positive perceptions of treatment efficacy and expressed enthusiasm for the treatments. Conclusion This study makes an important contribution to the research literature on the importance of environmental factors, concomitant impairments, and technology simplification when designing technology-based therapies intended to be self-administered at home. This study failed to show any added benefit of HTVG to CCFES therapy. Clinicaltrials.gov (NCT03058796).

Effectiveness and safety of virtual reality rehabilitation after stroke: an overview of systematic reviews

Virtual reality (VR) is an innovative neurorehabilitation modality that has been variously examined in systematic reviews. We assessed VR effectiveness and safety after cerebral stroke. In this overview of systematic reviews, we searched eleven databases (Cochrane Database of Systematic Reviews, EMBASE, MEDLINE, SCOPUS, ISI Web of Science, CINAHL, PsycINFO, Pedro, Otseeker, Healthevidence.org, Epistemonikos) and grey literature from inception to January 17, 2023. Studies eligible for inclusion were systematic reviews published in English that included adult patients with a clinical diagnosis of stroke (acute to chronic phase) undergoing any kind of immersive, semi-immersive or non-immersive VR intervention with or without conventional therapy versus conventional therapy alone. The primary outcome was motor upper limb function and activity. The secondary outcomes were gait and balance, cognitive and mental function, limitation of activities, participation, and adverse events. We calculated the degree of overlap between reviews based on the corrected covered area (CCA). Methodological quality was assessed using the A MeaSurement Tool to Assess systematic Reviews (AMSTAR 2) and the Certainty of Evidence (CoE) using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach. Discordances between results were examined using a conceptual framework based on the Jadad algorithm. This overview is registered with PROSPERO, CRD42022329263. Of the 58 reviews included (n=345 unique primary studies), 42 (72.4%) had conducted meta-analysis. More than half of the reviews (58.6%) were published between 2020 and 2022 and many (77.6%) were judged critically low in quality by AMSTAR 2. Most reported the Fugl Meyer Assessment scale (FMA-UE) to measure upper limb function and activity. For the primary outcome, there was a moderate overlap of primary studies (CCA 9.0%) with discordant findings. Focusing on upper limb function (FMA-UE), VR with or without conventional therapy seems to be more effective than conventional therapy alone, with low to moderate CoE and probable to definite clinical relevance. For secondary outcomes there was uncertainty about the superiority or no difference between groups due to substantial heterogeneity of measurement scales (eg, methodological choices). A few reviews (n=6) reported the occurrence of mild adverse events. Current evidence suggests that multiple meta-analyses agreed on the superiority of VR with or without conventional therapy over conventional therapy on FME-UE for upper limb. Clinicians may consider embedding VR technologies into their practice as appropriate with patient's goals, abilities, and preferences. However, caution is needed given the poor methodological quality of reviews. Italian Ministry of Health.

Assessing single camera markerless motion capture during upper limb activities of daily living

Assessing single camera markerless motion capture during upper limb activities of daily living

Upper limb practice with a dynamic hand orthosis to improve arm and hand function in people after stroke: a feasibility study

BackgroundDynamic hand orthosis may help upper limb recovery by keeping the wrist and hand in an optimal position while executing a grasp. Our aim was to investigate the feasibility of combining a dynamic hand orthosis with task-oriented upper limb practice after stroke.MethodFifteen adult stroke survivors were recruited in a single-group, pre-post intervention study. They received 12 weeks of task-oriented upper limb training with a dynamic hand orthosis with 3 weeks supervised at a community rehabilitation unit followed by 9 weeks unsupervised at home. Feasibility was determined by recruitment (proportion of eligible/enrolled and enrolled/retained participants), intervention (adherence, acceptability, and safety) and measurement (time taken to collect outcomes and proportion of participants where all measures were collected). Clinical outcomes were measured at baseline (Week 0), end of Week 3 and Week 12.ResultsFifteen (46%) of eligible volunteers were enrolled in the study. Eight (53%) of those enrolled completed the 12-week intervention. Eighty eight percent were satisfied or very satisfied with the dynamic hand orthosis. Clinical measures were collected for all participants at baseline and in all those who completed the intervention but often took over one hour to complete. At 12 weeks, participants had improved by 7 points out of 57 (95% CI 2 to 13) on the ARAT and by 8 points out of 66 (95% CI 0 to 15) on the FMA-UE.ConclusionThe intervention appears to be feasible in terms of acceptability and safety, while recruitment and measurement need further consideration. The magnitude of the clinical outcomes suggests that the intervention has a potential to improve both upper limb activity and impairment, and this study provides useful information for the design of a pilot randomized trial.Trial registrationClinicalTrials.gov Identifier: NCT03396939.

Effectiveness of virtual reality interventions of the upper limb in children and young adults with cerebral palsy: A systematic review with meta-analysis

Objective To examine the characteristics and the effectiveness of virtual reality systems on upper limb impairments in children and young adults with cerebral palsy. Data sources An electronic search was conducted on PubMed, PEDro, Web of Science, Central, and EMBASE. Methods The protocol of this review was prospectively registered in the PROSPERO database (CRD42022302271). Randomized controlled trials that tested the effects of virtual reality-based interventions on the upper limb of participants with cerebral palsy were included. The methodological quality of the studies was measured by the PEDro scale. The certainty of the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation. The data of the studies were analyzed in meta-analysis and presented in forest plots and narrative synthesis. Results Twenty-two studies involving 746 participants were included. Ten different virtual reality systems were used in the interventions, of which six were designed specifically for rehabilitation and four commercial video games. We found an effect in favor of virtual reality when it was used in combination with conventional therapy for upper limb activity (SMD = 0.65; 95% CI (0.19 to 1.11)). However, the certainty of the evidence of the comparisons ranged from very low to low. Conclusion Virtual reality seems to be an effective tool for upper limb activity in children and young adults with cerebral palsy. Nevertheless, future studies should present a better methodological quality, a larger sample size, and well-defined rehabilitation programs to reduce the inconsistency of the evidence in this domain.

Effect of motor relearning programme on neurological functions and level of disability on upper limb activity in post-stroke patients

Objective: To compare the effects of Motor Relearning Programme and Mirror Therapy on upper extremity functions in Post-Stroke patients. Design: Parallel group, randomized controlled trial Settings: The present study was conducted at OPD of University College of Physiotherapy, Faridkot, IPD and OPD of Department of Neurology and Neurosurgery of Guru Gobind Singh Medical College and Hospital, Faridkot,Punjab. Participants: A total of 45 post-stroke patients with upper limb impairent were randomly allocated into three equal groups comprises 15 patients each.Group A received Motor Relearning Programme (MRP) along with Conventional Physiotherapy (CPT), whereas Group B received Mirror Therapy (MT) along with CPT and Group C receivedCPT only. The total duration of intervention was 1 hour per session and frequency of 8 weeks, with 5 sessions per week. Main Outcome Measures: The outcome measures included were National Institutes of Health Stroke Scale (NIHSS) and Modified Rankin Scale (MRS). Results: The present study revealed that both parameters within the groups had significantly improved in the pre-intervention analysis. However, post-intervention scores of all the parameters of Group A revealed considerable high improvement at a significant level of (p<0.0001) when compared to the other two groups i.e. Group B and Group C. Conclusion: In light of the study's findings, it is concluded that the MRP along with CPT is more effective than MT along with CPT and CPT alone.

Detecting Asymmetry of Upper Limb Activity with Accelerometry in Infants at Risk for Unilateral Spastic Cerebral Palsy

Aims To examine whether accelerometry can quantitate asymmetry of upper limb activity in infants aged 3–12 months at risk for developing unilateral spastic cerebral palsy (USCP). Method A prospective study was performed in 50 infants with unilateral perinatal brain injury at high risk of developing USCP. Triaxial accelerometers were worn on the ipsilateral and contralesional upper limb during the Hand Assessment for Infants (HAI). Infants were grouped in three age intervals (3–5 months, 5–7.5 months and 7.5 until 12 months). Each age interval group was divided in a group with and without asymmetrical hand function based on HAI cutoff values suggestive of USCP. Results In a total of 82 assessments, the asymmetry index for mean upper limb activity was higher in infants with asymmetrical hand function compared to infants with symmetrical hand function in all three age groups (ranging from 41 to 51% versus − 2–6%, p < 0.01), while the total activity of both upper limbs did not differ. Conclusions Upper limb accelerometry can identify asymmetrical hand function in the upper limbs in infants with unilateral perinatal brain injury from 3 months onwards and is complementary to the Hand Assessment for Infants.

Quantitative measurement of finger usage in stroke hemiplegia using ring-shaped wearable devices

BackgroundIn post-stroke rehabilitation, positive use of affected limbs in daily life is important to improve affected upper-limb function. Several studies have quantitatively evaluated the amount of upper-limb activity, but few have measured finger usage. In this study, we used a ring-shaped wearable device to measure upper-limb and finger usage simultaneously in hospitalized patients with hemiplegic stroke and investigated the association between finger usage and general clinical evaluation.MethodsTwenty patients with hemiplegic stroke in an inpatient hospital participated in this study. All patients wore a ring-shaped wearable device on both hands for 9 h on the day of the intervention, and their finger and upper-limb usage were recorded. For the rehabilitation outcome assessments, the Fugl-Meyer Assessment of the Upper Extremity (FMA-UE), Simple Test for Evaluating Hand Function (STEF), Action Research Arm Test (ARAT), Motor Activity Log-14 (MAL), and Functional Independence Measure Motor (FIM-m) were performed and evaluated on the same day as the intervention.ResultsFinger usage of the affected hand was moderately correlated with STEF (r=0.48, p<0.05) and STEF ratio (r=0.47, p<0.05). The finger-usage ratio was moderately correlated with FMA-UE (r=0.56, p<0.05) and ARAT (r=0.53, p<0.05), and strongly correlated with STEF (r=0.80, p<0.01) and STEF ratio (r=0.80, p<0.01). The upper-limb usage of the affected side was moderately correlated with FMA-UE (r=0.46, p<0.05), STEF (r=0.55, p<0.05) and STEF ratio (r=0.54, p<0.05), and strongly correlated with ARAT (r=0.57, p<0.01). The upper-limb usage ratio was moderately correlated with ARAT (r=0.48, p<0.05) and STEF (r=0.55, p<0.05), and strongly correlated with the STEF ratio (r=0.61, p<0.01). By contrast, there was no correlation between MAL and any of the measurements.ConclusionsThis measurement technique provided useful information that was not biased by the subjectivity of the patients and therapists.

Characterization of upper limb use in health care workers during regular shifts: A quantitative approach based on wrist-worn accelerometers

Despite the high prevalence of upper limb (UL) work-related musculoskeletal disorders (WRMSD) among health care workers (HCWs), little is known about their relationship with exposure to biomechanical risk factors. This study aimed to assess UL activity features under actual working conditions using two wrist-worn accelerometers. Accelerometric data were processed to obtain duration, intensity, and asymmetry of UL use in 32 HCWs during the execution of commonly performed tasks (e.g., patient hygiene, transfer, and meal distribution) within a regular shift. The results show that such tasks are characterized by significantly different patterns of UL use, in particular, higher intensities and larger asymmetries were observed respectively for patient hygiene and meal distribution. The proposed approach appears, thus, suitable to discriminate tasks characterized by different UL motion patterns. Future studies could benefit from the integration of such measures with self-reported workers’ perception to elucidate the relationship between dynamic UL movements and WRMSD.

TWO CASES OF UPPER EXTREMITY DEEP VEIN THROMBOSIS IN ICU SETTING – A RARE CONDITION

Upper extremity deep venous thrombosis (UEDVT) occurs either spontaneously, as a consequence of strenuous upper limb activity (also known as the Paget - Schroetter syndrome) or secondary to an underlying cause like thrombosis due to devices like central venous catheter. Primary and secondary UEDVT differs in long-term sequelae and mortality. It is less common phenomenon and accounts for approximately 5-10 percent of all cases of DVT. We are presenting two such cases of upper limb DVT encountered in our ICU. It is important that clinicians remain on high alert for prompt diagnosis and early recognition to provide early treatment and avoid potential complications such as pulmonary embolism.

Role of Bobath and Task Specific Approach to Improve Upper Limb Activity of Daily Living among the Individual with Chronic Stroke - A Review Study

Role of Bobath and Task Specific Approach to Improve Upper Limb Activity of Daily Living among the Individual with Chronic Stroke - A Review Study

Predicting later categories of upper limb activity from earlier clinical assessments following stroke: an exploratory analysis

BackgroundAccelerometers allow for direct measurement of upper limb (UL) activity. Recently, multi-dimensional categories of UL performance have been formed to provide a more complete measure of UL use in daily life. Prediction of motor outcomes after stroke have tremendous clinical utility and a next step is to explore what factors might predict someone’s subsequent UL performance category.PurposeTo explore how different machine learning techniques can be used to understand how clinical measures and participant demographics captured early after stroke are associated with the subsequent UL performance categories.MethodsThis study analyzed data from two time points from a previous cohort (n = 54). Data used was participant characteristics and clinical measures from early after stroke and a previously established category of UL performance at a later post stroke time point. Different machine learning techniques (a single decision tree, bagged trees, and random forests) were used to build predictive models with different input variables. Model performance was quantified with the explanatory power (in-sample accuracy), predictive power (out-of-bag estimate of error), and variable importance.ResultsA total of seven models were built, including one single decision tree, three bagged trees, and three random forests. Measures of UL impairment and capacity were the most important predictors of the subsequent UL performance category, regardless of the machine learning algorithm used. Other non-motor clinical measures emerged as key predictors, while participant demographics predictors (with the exception of age) were generally less important across the models. Models built with the bagging algorithms outperformed the single decision tree for in-sample accuracy (26–30% better classification) but had only modest cross-validation accuracy (48–55% out of bag classification).ConclusionsUL clinical measures were the most important predictors of the subsequent UL performance category in this exploratory analysis regardless of the machine learning algorithm used. Interestingly, cognitive and affective measures emerged as important predictors when the number of input variables was expanded. These results reinforce that UL performance, in vivo, is not a simple product of body functions nor the capacity for movement, instead being a complex phenomenon dependent on many physiological and psychological factors. Utilizing machine learning, this exploratory analysis is a productive step toward the prediction of UL performance.Trial registration NA

Upper Limb Function Recovery by Combined Repetitive Transcranial Magnetic Stimulation and Occupational Therapy in Patients with Chronic Stroke According to Paralysis Severity.

Repetitive transcranial magnetic stimulation (rTMS) with intensive occupational therapy improves upper limb motor paralysis and activities of daily living after stroke; however, the degree of improvement according to paralysis severity remains unverified. Target activities of daily living using upper limb functions can be established by predicting the amount of change after treatment for each paralysis severity level to further aid practice planning. We estimated post-treatment score changes for each severity level of motor paralysis (no, poor, limited, notable, and full), stratified according to Action Research Arm Test (ARAT) scores before combined rTMS and intensive occupational therapy. Motor paralysis severity was the fixed factor for the analysis of covariance; the delta (post-pre) of the scores was the dependent variable. Ordinal logistic regression analysis was used to compare changes in ARAT subscores according to paralysis severity before treatment. We implemented a longitudinal, prospective, interventional, uncontrolled, and multicenter cohort design and analyzed a dataset of 907 patients with stroke hemiplegia. The largest treatment-related changes were observed in the Limited recovery group for upper limb motor paralysis and the Full recovery group for quality-of-life activities using the paralyzed upper limb. These results will help predict treatment effects and determine exercises and goal movements for occupational therapy after rTMS.

The effects of combined high-frequency repetitive transcranial magnetic stimulation and cervical nerve root magnetic stimulation on upper extremity motor recovery following stroke.

Upper limb motor impairments after stroke cause patients partial or total loss of the capability of performing daily living, working, and social activities, which significantly affects the quality of life (QoL) of patients and brings a heavy burden to their families and society. As a non-invasive neuromodulation technique, transcranial magnetic stimulation (TMS) can act not only on the cerebral cortex, but also on peripheral nerves, nerve roots, and muscle tissues. Previous studies have shown that magnetic stimulation on the cerebral cortex and peripheral tissues has a positive effect on the recovery of upper limb motor function after stroke, however, few studies have reported the combination of the two. This study was to investigate whether high frequency repetitive transcranial magnetic stimulation (HF-rTMS) combined with cervical nerve root magnetic stimulation more effectively ameliorates upper limb motor function in stroke patients. We hypothesized that the combination of the two can achieve a synergistic effect and further promotes functional recovery. Sixty patients with stroke were randomly divided into four groups and received real or sham rTMS stimulation and cervical nerve root magnetic stimulation consecutively before other therapies, once daily over five fractions per week for a total of 15 times. We evaluated the upper limb motor function and activities of daily living of the patients at the time of pre-treatment, post-treatment, and 3-month follow up. All patients completed study procedures without any adverse effects. The upper limb motor function and activities of daily living improved in patients of each group were improved after treatment (post 1) and 3 months after treatment (post 2). Combination treatment was significantly better than single treatments alone or sham. Both rTMS and cervical nerve root magnetic stimulation effectively promoted upper limb motor recovery in patients with stroke. The protocol combining the two is more beneficial for motor improvement and patients can easily tolerate it. https://www.chictr.org.cn/, identifier ChiCTR2100048558.

The relationship between self-reported physical frailty and sensor-based physical activity measures in older adults – a multicentric cross-sectional study

BackgroundThe decline in everyday life physical activity reflects and contributes to the frailty syndrome. While especially self-reported frailty assessments have the advantage of reaching large groups at low costs, little is known about the relationship between the self-report and objective measured daily physical activity behavior.The main objective was to evaluate whether and to what extent a self-reported assessment of frailty is associated with daily physical activity patterns.MethodsDaily activity data were obtained from 88 elderly participants (mean 80.6 ± 9.1 years) over up to 21 days. Acceleration data were collected via smartwatch. According to the results of a self-report frailty questionnaire, participants were retrospectively split up into three groups, F (frail, n = 43), P (pre-frail, n = 33), and R (robust, n = 12). Gait- and activity-related measures were derived from the built-in step detector and acceleration sensor and comprised, i.a., standard deviation of 5-s-mean amplitude deviation (MADstd), median MAD (MADmedian), and the 95th percentile of cadence (STEP95). Parameters were fed into a PCA and component scores were used to derive behavioral clusters.ResultsThe PCA suggested two components, one describing gait and one upper limb activity. Mainly gait related parameters showed meaningful associations with the self-reported frailty score (STEP95: R2 = 0.25), while measures of upper limb activity had lower coefficients (MADmedian: R2 = 0.07). Cluster analysis revealed two clusters with low and relatively high activity in both dimensions (cluster 2 and 3). Interestingly, a third cluster (cluster 1) was characterized by high activity and low extent of ambulation. Comparisons between the clusters showed significant differences between activity, gait, age, sex, number of chronic diseases, health status, and walking aid. Particularly, cluster 1 contained a higher number of female participants, whose self-reports tended towards a low health status, the frequent use of a walking aid, and a higher score related to frailty questions.ConclusionsThe results demonstrate that subjective frailty assessments may be a simple first screening approach. However, especially older women using walking aids may classify themselves as frail despite still being active. Therefore, the results of self-reports may be particularly biased in older women.

Time-Based and Path-Based Analysis of Upper-Limb Movements during Activities of Daily Living.

Patients after stroke need to re-learn functional movements required for independent living throughout the rehabilitation process. In the study, we used a wearable sensory system for monitoring the movement of the upper limbs while performing activities of daily living. We implemented time-based and path-based segmentation of movement trajectories and muscle activity to quantify the activities of the unaffected and the affected upper limbs. While time-based segmentation splits the trajectory in quants of equal duration, path-based segmentation isolates completed movements. We analyzed the hand movement path and forearm muscle activity and introduced a bimanual movement parameter, which enables differentiation between unimanual and bimanual activities. The approach was validated in a study that included a healthy subject and seven patients after stroke with different levels of disabilities. Path-based segmentation provides a more detailed and comprehensive evaluation of upper limb activities, while time-based segmentation is more suitable for real-time assessment and providing feedback to patients. Bimanual movement parameter effectively differentiates between different levels of upper limb involvement and is a clear indicator of the activity of the affected limb relative to the unaffected limb.

Quantitative assessment of trunk movements in functional reaching in children and adolescents with dyskinetic cerebral palsy

BackgroundTrunk control and upper limb function are often disturbed in people with dyskinetic cerebral palsy. While trunk control is fundamental in upper limb activities, insights in trunk control in dyskinetic cerebral palsy are missing. This study aimed to determine trunk movement characteristics in individuals with dyskinetic cerebral palsy during reaching. MethodsTwenty individuals with dyskinetic cerebral palsy (MACS level I-III (16y6m)) and 20 typical developing peers (17y2m) were included. Participants performed three tasks: reach forward, reach sideways, and reach and grasp vertically, using a cross-sectional study design. Movements were analyzed using 3D motion capture and a sensor on the trunk. Trunk range of motion, joint angle at point of task achievement, peak and range of angular velocity and linear acceleration were compared between groups using Mann-Whitney U and independent t-tests. FindingsParticipants with dyskinetic cerebral palsy showed higher trunk range of motion in all planes during reach forward and reach and grasp vertically, and in rotation and lateral flexion during reach sideways. During reach and grasp vertically, the joint angle at point of task achievement differed in the transversal plane. Ranges of angular velocity and linear acceleration were higher for all tasks and planes for participants with dyskinetic cerebral palsy, and for peak values in nearly all planes. InterpretationCurrent results provide insights in trunk control at population level. This is a first step towards a better and individualized evaluation and treatment for trunk control, being an important factor in improving functional activities for individuals with dyskinetic cerebral palsy.

Restoring Voluntary Bimanual Activities of Patients with Chronic Hemiparesis through a Foot-Controlled Hand/Forearm Exoskeleton.

A significant number of stroke patients are permanently left with a hemiparetic upper limb after the poststroke six-month golden recovery period, resulting in a drastic decline in their quality of life. This study develops a novel foot-controlled hand/forearm exoskeleton that enables patients with hemiparetic hands and forearms to restore their voluntary activities of daily living. Patients can accomplish dexterous hand/arm manipulation on their own with the assistance of a foot-controlled hand/forearm exoskeleton by utilizing foot movements on the unaffected side as command signals. The proposed foot-controlled exoskeleton was first tested on a stroke patient with a chronic hemiparetic upper limb. The testing results showed that the forearm exoskeleton can assist the patient in achieving approximately 107°of voluntary forearm rotation with a static control error less than 1.7°, whereas the hand exoskeleton can assist the patient in realizing at least six different voluntary hand gestures with a success rate of 100%. Further experiments involving more patients demonstrated that the foot-controlled hand/forearm exoskeleton can help patients in restoring some of the voluntary activities of daily living with their paretic upper limb, such as picking up food to eat and opening water bottles to drink, and etc. This research implies that the foot-controlled hand/forearm exoskeleton is a viable way to restore the upper limb activities of stroke patients with chronic hemiparesis.

Effects of motor pacing on frontal-hemodynamic responses during continuous upper-limb and whole-body movements.

Advances in timing research advocate for the existence of two timing mechanisms (automatic vs. controlled) that are related to the level of cognitive control intervening for motor behavior regulation. In the present study, we used the functional near-infrared spectroscopy (fNIRS) cutting-edge technique to examine the hypothesis that prefrontal inhibitory control is needed to perform slow motor activities. Participants were asked to perform a sensorimotor-synchronization task at various paces (i.e., slow, close-to-spontaneous, fast). We contrasted upper-limb circle drawing to a more naturalistic behavior that required whole-body movements (i.e., steady-state walking). Results indicated that whole-body movements led to greater brain oxygenation over the motor regions when compared with upper-limb activities. The effect of motor pace was found in the walking task only, with more bilateral orbitofrontal and left dorsolateral activation at slow versus fast pace. Exploratory analyses revealed a positive correlation between the activation of the orbitofrontal and motor areas for the close-to-spontaneous pace in both tasks. Overall, results support the key role of prefrontal cognitive control in the production of slow whole-body movements. In addition, our findings confirm that upper-limb (laboratory-based) tasks might not be representative of those engaged during everyday-life motor behaviors. The fNIRS technique may be a valuable tool to decipher the neurocognitive mechanisms underlying naturalistic, adaptive motor behaviors.