Soft, Lightweight Wearable Robots to Support the Upper Limb in Activities of Daily Living: A Feasibility Study on Chronic Stroke Patients.

Stroke can be a devastating condition that impairs the upper limb and reduces mobility. Wearable robots can aid impaired users by supporting performance of Activities of Daily Living (ADLs). In the past decade, soft devices have become popular due to their inherent malleable and low-weight properties that makes them generally safer and more ergonomic. In this study, we present an improved version of our previously developed gravity-compensating upper limb exosuit and introduce a novel hand exoskeleton. The latter uses 3D-printed structures that are attached to the back of the fingers which prevent undesired hyperextension of joints. We explored the feasibility of using this integrated system in a sample of 10 chronic stroke patients who performed 10 ADLs. We observed a significant reduction of 30.3 ± 3.5% (mean ± standard error), 31.2 ± 3.2% and 14.0 ± 5.1% in the mean muscular activity of the Biceps Brachii (BB), Anterior Deltoid (AD) and Extensor Digitorum Communis muscles, respectively. Additionally, we observed a reduction of 14.0 ± 11.5%, 14.7 ± 6.9% and 12.8 ± 4.4% in the coactivation of the pairs of muscles BB and Triceps Brachii (TB), BB and AD, and TB and Pectoralis Major (PM), respectively, typically associated to pathological muscular synergies, without significant degradation of healthy muscular coactivation. There was also a significant increase of elbow flexion angle ( 12.1±1.5° ). These results further cement the potential of using lightweight wearable devices to assist impaired users.

Robotic Assisted Upper Limb Training Post Stroke: A Randomized Control Trial Using Combinatory Approach Toward Reducing Workforce Demands.

Post stroke upper limb rehabilitation is a challenging problem with poor outcomes as 40% of survivors have functionally useless upper limbs. Robot-aided therapy (RAT) is a potential method to alleviate the effort of intensive, task-specific, repetitive upper limb exercises for both patients and therapists. The present study aims to investigate how a time matched combinatory training scheme that incorporates conventional and RAT, using H-Man, compares with conventional training toward reducing workforce demands. In a randomized control trial (NCT02188628, www.clinicaltrials.gov), 44 subacute to chronic stroke survivors with first-ever clinical stroke and predominant arm motor function deficits were recruited and randomized into two groups of 22 subjects: Robotic Therapy (RT) and Conventional Therapy (CT). Both groups received 18 sessions of 90 min; three sessions per week over 6 weeks. In each session, participants of the CT group received 90 min of 1:1 therapist-supervised conventional therapy while participants of the RT group underwent combinatory training which consisted of 60 min of minimally-supervised H-Man therapy followed by 30 min of conventional therapy. The clinical outcomes [Fugl-Meyer (FMA), Action Research Arm Test and, Grip Strength] and the quantitative measures (smoothness, time efficiency, and task error, derived from two robotic assessment tasks) were independently evaluated prior to therapy intervention (week 0), at mid-training (week 3), at the end of training (week 6), and post therapy (week 12 and 24). Significant differences within group were observed at the end of training for all clinical scales compared with baseline [mean and standard deviation of FMA score changes between baseline and week 6; RT: Δ4.41 (3.46) and CT: Δ3.0 (4.0); p < 0.01]. FMA gains were retained 18 weeks post-training [week 24; RT: Δ5.38 (4.67) and week 24 CT: Δ4.50 (5.35); p < 0.01]. The RT group clinical scores improved similarly when compared to CT group with no significant inter-group at all time points although the conventional therapy time was reduced to one third in RT group. There were no training-related adverse side effects. In conclusion, time matched combinatory training incorporating H-Man RAT produced similar outcomes compared to conventional therapy alone. Hence, this study supports a combinatory approach to improve motor function in post-stroke arm paresis. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT02188628.

A preliminary study on the relationship between proprioceptive deficits and motor functions in chronic stroke patients.

Although motor and sensory impairments of the upper limb after stroke have been widely studied, the relationship between sensory deficits and motor functions has been less thoroughly explored. In this ongoing study, we investigated the relationship between proprioceptive impairments and motor functions with 20 chronic stroke survivors. Their proprioceptive abilities were assessed with a passive joint position matching test using H-Man and their motor functions were assessed with ARAT (Action Research Arm Test) and FMA (Fugl Meyer Upper Extremity Assessment) clinical scores. The assessments were conducted before, during and after the therapy. Results indicated a significant difference between the proprioceptive outcomes of healthy and stroke participants (at baseline) in both matching accuracy (absolute error, p=0.02) and precision (variability of the signed error, p=0.03). Significant correlations were found between the proprioceptive assessment outcomes (assessed before the beginning of the motor rehabilitation) of stroke participants with impaired proprioception and their ARAT clinical scores assessed at the first follow-up (week 12) (rho =- 0.74 and p=0.047 for the absolute error; rho =-0.78 and p= 0.03 for the variability of the signed error). The results from this preliminary study indicated a significant relationship between proprioceptive impairments and motor function performances in proprioceptively impaired chronic stroke participants.

Work with me, not for me: Relationship between robotic assistance and performance in subacute and chronic stroke patients.

INTRODUCTION: Studies in robotic therapy which applied the performance enhancement approach report improvements in motor performance during training, though these improvements do not always transfer to motor learning. OBJECTIVES: We postulate that there exists an assistance threshold for which performance saturates. Above this threshold, the robot's input outweighs the patient's input and likely learning is not fostered. This study investigated the relationship between assistance and performance changes in stroke patients to find the assistance threshold for performance saturation. METHODS: Twelve subacute and chronic stroke patients engaged in five sessions (over two weeks, each 60 min) in which they performed a reaching task with the rehabilitation robot H-Man in presence of varying levels of haptic assistance (50 N/m to 290 N/m, randomized order). In two additional sessions, a therapist manually tuned the assistance to promote maximal motor learning. RESULTS: Higher levels of assistance resulted in smoother and faster performance that saturated at assistance levels with K ≥ 110 N/m. Also, the therapist selected assistance levels of K = 175 N/m or below. CONCLUSION: The findings of the study indicate that low levels of assistance (K ≤ 175 N/m) can sufficiently induce a significant change in performance.

Efficacy of a Virtual Reality Commercial Gaming Device in Upper Limb Recovery after Stroke: A Randomized, Controlled Study.

OBJECTIVE: To compare the efficacy of a virtual reality commercial gaming device, Nintendo wii (NW) with conventional therapy and customary care in facilitating upper limb recovery after stroke. DESIGN: Randomized, controlled, single-blinded study. SETTING: Tertiary rehabilitation center. PARTICIPANTS: 105 subjects admitted to in inpatient rehabilitation program within 6 weeks of stroke onset. INTERVENTIONS: Subjects were randomly assigned to one of three groups of upper limb exercises: (1) NW gaming; (2) conventional therapy; (3) control. NW gaming and conventional therapy were provided fourtimes a week for 3 weeks. MAIN OUTCOME MEASURE(S): The main outcome measure was Fugl-Meyer assessment (FMA) of upper limb function. Secondary outcome measures included Action Research Arm Test, Functional Independence Measure, and Stroke Impact Scale. These measures were assessed at baseline, completion of intervention (week 3) and at 4 weeks and 8 weeks after completion of intervention. The primary outcome measure was the change in FMA scores at completion of intervention. RESULTS: The mean age was 57.5±9.8 years, and subjects were enrolled at a mean of 13.7±8.9 days after stroke. The mean baseline FMA score was 16.4±14.2. There was no difference in FMA scores between all 3 groups at the end of intervention, and at 4 and 8 weeks after completion of intervention. Similar findings were also noted for the secondary outcome measures. CONCLUSION(S): Twelve sessions of augmented upper limb exercises via NW gaming or conventional therapy over a 3-week period was not effective in enhancing upper limb motor recovery compared to control.

A double-blind, placebo-controlled, randomized phase II pilot study to investigate the potential efficacy of the traditional chinese medicine Neuroaid (MLC 601) in enhancing recovery after stroke (TIERS).

BACKGROUND AND OBJECTIVE: Previous clinical studies have shown that Neuroaid (MLC 601) may be beneficial in post-stroke rehabilitation. Our aim was to investigate the efficacy of Neuroaid on motor recovery in ischemic stroke patients using rehabilitation endpoints in accordance with the International Conference on Harmonization/Good Clinical Practice guidelines, in order to provide predictive information for further larger trials. METHODS: This is a phase II double-blind, placebo-controlled pilot study of 40 subjects admitted with a recent (less than 1 month) ischemic stroke. All subjects were given either Neuroaid or placebo, 4 capsules 3 times a day for 4 weeks. Fugl-Meyer Assessment (FMA), National Institutes of Health Stroke Scale and Functional Independence Measure scores were measured at initiation of the treatment, and at 4 and 8 weeks. RESULTS: None of the outcomes was statistically significant between the two groups. However, FMA scores showed a positive trend for improvement with Neuroaid treatment over time. Subgroup analysis of subjects with posterior circulation infarction and severe stroke both showed a tendency for better recovery. CONCLUSION: Some positive trends were observed in the Neuroaid group. A larger multicenter trial focusing on severe stroke patients is needed to better evaluate the role of Neuroaid in aiding stroke recovery in rehabilitation.