Comparative effects of EMG-driven robot-assisted therapy versus task-oriented training on motor and daily function in patients with stroke: a randomized cross-over trial

Background Robot-assisted hand training has shown positive effects on promoting neuromuscular control. Since both robot-assisted therapy and task-oriented training are often used in post-stroke rehabilitation, we raised the question of whether two interventions engender differential effects in different domains. Methods The study was conducted using a randomized, two-period crossover design. Twenty-four chronic stroke survivors received a 12-session robot-assisted intervention followed by a 12-session task-oriented intervention or vice versa. A 1-month washout period between each intervention was implemented. Outcome measures were evaluated before the intervention, after the first 12-session intervention, and after the second 12-session intervention. Clinical assessments included Fugl-Meyer Assessment for Upper Extremity, Wolf Motor Function Test, Action Research Arm Test and Motor Activity Log. Results Our findings suggested that EMG-driven robot-assisted therapy was as effective as task-oriented training in terms of improving upper limbs functional performance in activity domain, and robot-assisted therapy was more effective in improving movement duration during functional tasks. Task-oriented training showed better improvement in body function domain and activity and participation domain, especially in improving spontaneous use of affected arm during daily activities. Conclusions Both intervention protocol had their own advantages in different domains, and robot-assisted therapy may save manpower and be considered as an alternative intervention to task-oriented training. Combining the two approaches could yield results greater than either alone, which awaits further study. Trial registration: ClinicalTrials.gov Identifier: NCT03624153. Registered on 9th August 2018, https://clinicaltrials.gov/ct2/show/NCT03624153.

Genetic Factors, Brain Atrophy, and Response to Rehabilitation Therapy After Stroke

Objective Patients show substantial differences in response to rehabilitation therapy after stroke. We hypothesized that specific genetic profiles might explain some of this variance and, secondarily, that genetic factors are related to cerebral atrophy post-stroke. Methods The phase 3 ICARE study examined response to motor rehabilitation therapies. In 216 ICARE enrollees, DNA was analyzed for presence of the BDNF val66met and the ApoE ε4 polymorphism. The relationship of polymorphism status to 12-month change in motor status (Wolf Motor Function Test, WMFT) was examined. Neuroimaging data were also evaluated (n=127). Results Subjects were 61±13 years old (mean±SD) and enrolled 43±22 days post-stroke; 19.7% were BDNF val66met carriers and 29.8% ApoE ε4 carriers. Carrier status for each polymorphism was not associated with WMFT, either at baseline or over 12 months of follow-up. Neuroimaging, acquired 5±11 days post-stroke, showed that BDNF val66met polymorphism carriers had a 1.34-greater degree of cerebral atrophy compared to non-carriers (P=.01). Post hoc analysis found that age of stroke onset was 4.6 years younger in subjects with the ApoE ε4 polymorphism (P=.02). Conclusion Neither the val66met BDNF nor ApoE ε4 polymorphism explained inter-subject differences in response to rehabilitation therapy. The BDNF val66met polymorphism was associated with cerebral atrophy at baseline, echoing findings in healthy subjects, and suggesting an endophenotype. The ApoE ε4 polymorphism was associated with younger age at stroke onset, echoing findings in Alzheimer’s disease and suggesting a common biology. Genetic associations provide insights useful to understanding the biology of outcomes after stroke.

Efficacy of a Forearm Rotation Orthosis for People With a Hemiparetic Arm

Importance: Insufficient voluntary forearm movements are associated with ineffective and inefficient functional performance among people poststroke. Although evidence supports the application of the occupational therapy task-oriented (OTTO) approach for this population, the training protocol does not explicitly address the role of forearm rotation movements. In addition, a need exists for theoretical support for orthotic interventions for people poststroke. Objective: To examine the efficacy of (1) a forearm rotation orthosis, (2) the OTTO approach, and (3) the combination of the two with people poststroke with a hemiparetic arm. Design: Stratified, randomized, two-group, single-blinded, repeated-measures design. Setting: Rehabilitation clinic. Participants: Participants (N = 14) with a diagnosis of stroke and at least 10° of voluntary shoulder and elbow movement. Intervention: Participants were stratified into three groups by motor function (mild, moderate, severe) and randomly assigned either to 6 wk of no treatment followed by 6 wk of OTTO or to 6 wk of orthotic intervention followed by 6 wk of orthosis plus OTTO. Outcomes and Measures: Primary outcome measures were the Canadian Occupational Performance Measure (COPM), Wolf Motor Function Test (WMFT), and Motor Activity Log (MAL), administered at baseline (Week 1), at the end of Phase 1 (Week 7), and at the end of Phase 2 (Week 15) by blinded evaluators. Results: Both groups showed clinically important improvements on the COPM. No significant differences were found on the WMFT or MAL. Conclusions and Relevance: The OTTO intervention provides clinically important benefits in self-perceived functional performance to people poststroke. What This Article Adds: The OTTO approach is an occupation-focused intervention that aims at functional performance and emphasizes clients' active engagement throughout the process. The findings suggest that the protocol of the OTTO intervention and its efficacy are appropriate for clinical practice.

Using Subthreshold Vibratory Stimulation During Poststroke Rehabilitation Therapy: A Case Series

Subthreshold vibratory stimulation to the paretic wrist has been shown to prime the sensorimotor cortex and improve 2-week upper extremity (UE) therapy outcomes. The objective of this work was to determine feasibility, safety, and preliminary efficacy of the stimulation over a typical 6-week therapy duration. Four chronic stroke survivors received stimulation during 6-week therapy. Feasibility/safety/efficacy were assessed at baseline, posttherapy, and 1-month follow-up. For feasibility, all participants wore the device throughout therapy and perceived the stimulation comfortable/safe. Regarding safety, no serious/moderate intervention-related adverse events occurred. For efficacy, all participants improved in Wolf Motor Function Test and UE use in daily living based on accelerometry and stroke impact scale. Mean improvements at posttherapy/follow-up were greater than the minimal detectable change/clinically important difference and other trials with similar therapy without stimulation. In conclusion, the stimulation was feasible/safe for 6-week use. Preliminary efficacy encourages a larger trial to further evaluate the stimulation as a therapy adjunct.

The Effects of Distributed vs. Condensed Schedule for Robot-Assisted Training with Botulinum Toxin A Injection for Spastic Upper Limbs in Chronic Post-Stroke Subjects

Robot-assisted training (RT) combined with a Botulinum toxin A (BoNT-A) injection has been suggested as a means to optimize spasticity treatment outcomes. The optimal schedule of applying RT after a BoNT-A injection has not been defined. This single-blind, randomized controlled trial compared the effects of two predefined RT approaches as an adjunct to BoNT-A injections of spastic upper limbs in chronic post-stroke subjects. Thirty-six patients received a BoNT-A injection in the affected upper extremity and were randomly assigned to the condensed or distributed RT group. The condensed group received an intervention of four sessions/week for six consecutive weeks. The distributed group attended two sessions/week for 12 consecutive weeks. Each session included 45 min of RT using the InMotion 2.0 robot, followed by 30 min of functional training. The Fugl-Meyer Assessment, Modified Ashworth Scale, Wolf Motor Function Test, Motor Activity Log, and Stroke Self-Efficacy Questionnaire were assessed at pre-training, mid-term, post-training, and at 6 week follow-up, with the exception of the Motor Activity Log, which did not include mid-term measures. After the intervention, both groups had significant improvements in all outcome measures (within-group effects, p < 0.05), with the exception of the Wolf Motor Function Test time score. There were no significant differences between groups and interaction effects in all outcome measures. Our findings suggest that RT provided in a fixed dosage as an adjunct to a BoNT-A injection has a positive effect on participants’ impairment and activity levels, regardless of treatment frequency. (ClinicalTrials.gov: NCT03321097).

Revisiting Poststroke Upper Limb Stratification: Resilience in a Larger Cohort

Background Upper limb (UL) impairment in stroke survivors is both multifactorial and heterogeneous. Stratification of motor function helps identify the most sensitive and appropriate assessments, which in turn aids the design of effective and individualized rehabilitation strategies. We previously developed a stratification method combining the Grooved Pegboard Test (GPT) and Box and Block Test (BBT) to stratify poststroke UL motor function. Objective To investigate the resilience of the stratification method in a larger cohort and establish its appropriateness for clinical practice by investigating limitations of the GPT completion time. Methods Post hoc analysis of motor function for 96 community-dwelling participants with stroke (n = 68 male, 28 female, age 60.8 ± 14 years, 24.4 ± 36.6 months poststroke) was performed using the Wolf Motor Function Test (WMFT), Fugl-Meyer Assessment (F-M), BBT, and GPT. Hypothesis-free and hypothesis-based hierarchical cluster analyses were conducted to determine the resilience of the stratification method. Results The hypothesis-based analysis identified the same functional groupings as the hypothesis-free analysis: low (n = 32), moderate (n = 26), and high motor function (n = 38), with 3 exceptions. Thirty-three of the 38 participants with fine manual dexterity completed the GPT in ≤5 minutes. The remaining 5 participants took 6 to 25 minutes to place all 25 pegs but used alternative movement strategies to complete the test. The GPT time restriction changed the functional profile of the moderate and high motor function groups leading to more misclassifications. Conclusion The stratification method unambiguously classifies participants by UL motor function. While the inclusion of a 5-minute cutoff time for the GPT is preferred for clinical practice, it is not recommended for stratification purposes.

Safety, Feasibility, and Acceptability of a New Virtual Rehabilitation Platform: A Supervised Pilot Study

Purpose: Stroke is the leading cause of disability in adults worldwide, with hemiparesis being the most prevalent consequence. The use of video games and movement sensors could contribute to improving patients’ chances of recovery. We performed a supervised pilot study to validate the safety, feasibility, and acceptability of a new virtual rehabilitation platform in patients with chronic post-stroke upper limb hemiparesis. Methods: The participants (n = 9) participated in 40 rehabilitation sessions, twice a week, for a period of 20 weeks. Their experiences with the platform were documented using a Likert-scale survey. Changes in motor function were evaluated using the Chedoke Arm and Hand Activity Inventory (CAHAI) and the Wolf Motor Function Test (WMFT). Results and conclusions: All participants expressed that they enjoyed the experience and felt comfortable using the platform. Preliminary results showed significant motor recovery ( P = .0039) according to the WMFT scores. Patients with significant impairment showed no improvement in upper limb task-oriented motor function after therapy. The new platform is safe and well-accepted by patients. The improvement in motor function observed in some of the participants should be attributed to the therapy since spontaneous functional recovery is not expected in chronic stroke patients.

Effects of robot viscous forces on arm movements in chronic stroke survivors: a randomized crossover study

Background Our previous work showed that speed is linked to the ability to recover in chronic stroke survivors. Participants moving faster on the first day of a 3-week study had greater improvements on the Wolf Motor Function Test. Methods We examined the effects of three candidate speed-modifying fields in a crossover design: negative viscosity, positive viscosity, and a “breakthrough” force that vanishes after speed exceeds an individualized threshold. Results Negative viscosity resulted in a significant speed increase when it was on. No lasting after effects on movement speed were observed from any of these treatments, however, training with negative viscosity led to significant improvements in movement accuracy and smoothness. Conclusions Our results suggest that negative viscosity could be used as a treatment to augment the training process while still allowing participants to make their own volitional motions in practice. Trial registration This study was approved by the Institutional Review Boards at Northwestern University (STU00206579) and the University of Illinois at Chicago (2018-1251).

Upper Limb Motor Improvement after TBI: Systematic Review of Interventions

Traumatic Brain Injury (TBI) is a leading cause of adult morbidity and mortality. Individuals sustaining a TBI have impairments in both cognitive and motor domains. Motor improvements post-TBI are attributable to adaptive neuroplasticity and motor learning. Majority of the studies focus on remediation of balance and mobility impairments. There is limited understanding on the use of interventions for upper limb (UL) motor improvements in this population. We examined the evidence regarding the effectiveness of different interventions to augment UL motor improvement after a TBI. We systematically reviewed the literature published in English from 1990-2020. The modified Down’s and Black checklist helped assess study quality (total score:28). Studies were classified as excellent:24-28, good:19-23, fair:14-18 and poor:≤13 in quality. Effect sizes helped quantify intervention effectiveness. Twenty-three studies were retrieved. Study quality was excellent (n=1), good (n=4) or fair (n=19). Interventions used included strategies to decrease spasticity [Botulinum toxin provision (n=2), serial casting, soft splinting, tizanidine and acupuncture (n=1 each)], constraint induced movement therapy (n=4), virtual reality gaming (n=5), noninvasive stimulation (n=3), arm motor ability training (n=1), stem-cell transplant (n=1); task-oriented training (n=2) and augmented feedback (n=1). Motor impairment outcomes included Fugl-Meyer Assessment, Modified Ashworth Scale and kinematic outcomes (error and movement straightness). Activity limitation outcomes included Wolf Motor Function Test and Motor Activity Log. Effect sizes for majority of the interventions ranged from medium (0.5-0.79) to large (≥0.8). Only ten studies included retention testing. Results suggest that using these interventions can reduce UL motor impairment and improve activity performance after a TBI.