Perspectives on factors influencing quality of life in persons with long-term spinal cord injury: a qualitative study.

STUDY DESIGN: Qualitative Cohort Study. OBJECTIVES: Many people with long-term spinal cord injury (SCI) develop adaptation strategies to succeed. Understanding the factors that support their capacity to adapt and develop is important to enhance quality of life of others with SCI. This study aims to learn how these factors influence how people with SCI attain and maintain optimal quality of life as time since injury grows. SETTING: IL, USA. METHODS: A qualitative approach using one-on-one structured interviews with 16 individuals with long-term SCI was used to elicit perspectives of topics of importance. Analysis of these topics was done for the entire group, and for subgroups based on injury duration, i.e., 1-5 years, 5-15 years, and 15+ years post-injury. Deductive and inductive analyses of transcripts were performed. RESULTS: Five important themes emerged: 1. Injury, Medical Care, and Rehabilitation; 2. Built Environment and Accessibility; 3. Relationships and Support Systems; 4. Intrapersonal Thoughts and Emotions; and 5. Handling Challenges and Adversity. Topics of importance evolved over time. Most important were: 1-5 years: injury and recovery process; 5-15 years: navigating the community and how to handle difficult situations; and 15+ years: self-reflection and understanding how to handle challenges positively. CONCLUSIONS: Recognition of the factors (e.g. resilience, self-acceptance, built environment) that contribute to quality of life in people with SCI, and their prevalence over time, enables development of strategies to facilitate personal fulfillment and favorable adaptation at each stage. TRIAL REGISTRATION: This trial was posted on clinicaltrials.gov under NCT04544761.

Noninvasive spinal stimulation improves walking in chronic stroke survivors: a proof-of-concept case series.

BACKGROUND: After stroke, restoring safe, independent, and efficient walking is a top rehabilitation priority. However, in nearly 70% of stroke survivors asymmetrical walking patterns and reduced walking speed persist. This case series study aims to investigate the effectiveness of transcutaneous spinal cord stimulation (tSCS) in enhancing walking ability of persons with chronic stroke. METHODS: Eight participants with hemiparesis after a single, chronic stroke were enrolled. Each participant was assigned to either the Stim group (N = 4, gait training + tSCS) or Control group (N = 4, gait training alone). Each participant in the Stim group was matched to a participant in the Control group based on age, time since stroke, and self-selected gait speed. For the Stim group, tSCS was delivered during gait training via electrodes placed on the skin between the spinous processes of C5-C6, T11-T12, and L1-L2. Both groups received 24 sessions of gait training over 8 weeks with a physical therapist providing verbal cueing for improved gait symmetry. Gait speed (measured from 10 m walk test), endurance (measured from 6 min walk test), spatiotemporal gait symmetries (step length and swing time), as well as the neurophysiological outcomes (muscle synergy, resting motor thresholds via spinal motor evoked responses) were collected without tSCS at baseline, completion, and 3 month follow-up. RESULTS: All four Stim participants sustained spatiotemporal symmetry improvements at the 3 month follow-up (step length: 17.7%, swing time: 10.1%) compared to the Control group (step length: 1.1%, swing time 3.6%). Additionally, 3 of 4 Stim participants showed increased number of muscle synergies and/or lowered resting motor thresholds compared to the Control group. CONCLUSIONS: This study provides promising preliminary evidence that using tSCS as a therapeutic catalyst to gait training may increase the efficacy of gait rehabilitation in individuals with chronic stroke. Trial registration NCT03714282 (clinicaltrials.gov), registration date: 2018-10-18.

Implementation of Home-Based Telerehabilitation of Patients With Stroke in the United States: Protocol for a Realist Review.

BACKGROUND: Stroke is a common cause of mortality and morbidity. Insufficient and untimely rehabilitation has been associated with inadequate recovery. Telerehabilitation provides an opportunity for timely and accessible services for individuals with stroke, especially in remote areas. Telerehabilitation is defined as a health care team's use of a communication mode (eg, videoconferencing) to remotely provide rehabilitation services. Telerehabilitation is as effective as facility-based rehabilitation; however, it is infrequently used due to implementation barriers. OBJECTIVE: The aim of the study is to explore the interaction between the implementation strategies, context, and outcomes of telerehabilitation of patients with stroke. METHODS: This review will follow four steps: (1) defining the review scope, (2) literature search and quality appraisal, (3) data extraction and evidence synthesis, and (4) narrative development. PubMed via MEDLINE, the PEDro database, and CINAHL will be queried till June 2023 and supplemented with citation tracking and a gray literature search. The relevance and rigor of papers will be appraised using the TAPUPAS (Transparency, Accuracy, Purposivity, Utility, Propriety, Accessibility, and Specificity) and Weight of Evidence frameworks. The reviewers will extract and synthesize data iteratively and develop explanatory links between contexts, mechanisms, and outcomes. The results will be reported according to the Realist Synthesis publication standards set by Wong and colleagues in 2013. RESULTS: The literature search and screening will be completed in July 2023. Data extraction and analysis will be completed in August 2023, and findings will be synthesized and reported in October 2023. CONCLUSIONS: This will be the first realist synthesis, uncovering the causal mechanisms to explain how, why, and to what extent implementation strategies impact telerehabilitation adoption and implementation. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/47009.

Overground walking with a constraint force on the nonparetic leg during swing improves weight shift toward the paretic side in people after stroke.

Targeting enhancing the use of the paretic leg during locomotor practice might improve motor function of the paretic leg. The purpose of this study was to determine whether application of constraint force to the nonparetic leg in the posterior direction during overground walking would enhance the use of the paretic leg in people with chronic stroke. Fifteen individuals after stroke participated in two experimental conditions, i.e., overground walking with a constraint force applied to the nonparetic leg and overground walking only. Each participant was tested in the following procedures that consisted of overground walking with either constraint force or no constraint force, instrumented split-belt treadmill walking, and pressure-sensitive gait mat walking before and after the overground walking. Overground walking practice with constraint force resulted in greater enhancement in lateral weight shift toward the paretic side (P < 0.01), muscle activity of the paretic hip abductors (P = 0.04), and propulsion force of the paretic leg (P = 0.05) compared with the results of the no-constraint condition. Overground walking practice with constraint force tended to induce greater increase in self-selected overground walking speed (P = 0.06) compared with the effect of the no-constraint condition. The increase in propulsion force from the paretic leg was positively correlated with the increase in self-selected walking speed (r = 0.6, P = 0.03). Overground walking with constraint force applied to the nonparetic leg during swing phase of gait may enhance use of the paretic leg, improve weight shifting toward the paretic side and propulsion of the paretic leg, and consequently increase walking speed.NEW & NOTEWORTHY Application of constraint force to the nonparetic leg during overground walking induced improved lateral weight shifts toward the paretic leg and enhanced muscle activity of the paretic leg during walking. In addition, one session of overground walking with constraint force might induce an increase in propulsive force of the paretic leg and an increase in self-selected overground walking speed, which might be partially due to the improvement in motor control of the paretic leg.

Feasibility of PROMIS using computerized adaptive testing during inpatient rehabilitation.

BACKGROUND: There has been an increased significance on patient-reported outcomes in clinical settings. We aimed to evaluate the feasibility of administering patient-reported outcome measures by computerized adaptive testing (CAT) using a tablet computer with rehabilitation inpatients, assess workload demands on staff, and estimate the extent to which rehabilitation inpatients have elevated T-scores on six Patient Reported Outcomes Measurement Information System® (PROMIS®) measures. METHODS: Patients (N = 108) with stroke, spinal cord injury, traumatic brain injury, and other neurological disorders participated in this study. PROMIS computerized adaptive tests (CAT) were administered via a web-based platform. Summary scores were calculated for six measures: Pain Interference, Sleep Disruption, Anxiety, Depression, Illness Impact Positive, and Illness Impact Negative. We calculated the percent of patients with T-scores equivalent to 2 standard deviations or greater above the mean. RESULTS: During the first phase, we collected data from 19 of 49 patients; of the remainder, 61% were not available or had cognitive or expressive language impairments. In the second phase of the study, 40 of 59 patients participated to complete the assessment. The mean PROMIS T-scores were in the low 50 s, indicating an average symptom level, but 19-31% of patients had elevated T-scores where the patients needed clinical action. CONCLUSIONS: The study demonstrated that PROMIS assessment using a CAT administration during an inpatient rehabilitation setting is feasible with the presence of a research staff member to complete PROMIS assessment.

Enhanced phasic sensory afferents paired with controlled constraint force improve weight shift toward the paretic side in individuals post-stroke.

PURPOSE: The goal of this study was to determine whether enhanced phasic sensory afferent input paired with the application of controlled constraint force during walking would improve weight shift toward the paretic side and enhance use of the paretic leg. METHODS: Fourteen stroke survivors participated in two experimental conditions, sessions that consisted of 1 min treadmill walking without force and stimulation (baseline), 7 min walking with either "constraint force and sensory stimulation (constraint+stim)" or "constraint force only (constraint)" (adaptation), and then 2 min walking without force and stimulation (post-adaptation). Kinematics of the pelvis and legs, and muscle activity of the paretic leg were recorded. RESULTS: Participants showed greater increases in hip abductor (p < 0.001) and adductor (p = 0.04) muscle activities, weight shift toward the paretic side (p = 0.002), and step length symmetry (p < 0.01) during the late post-adaptation period in the "constraint+stim" condition, compared with the effect of the "constraint" condition. In addition, changes in overground walking speed from baseline to 10 min post treadmill walking was significantly greater for the "constraint force and stimulation" condition than for the "constraint force only" condition (p = 0.04). CONCLUSION: Enhanced targeted sensory afferent input during locomotor training may facilitate recruitment of targeted muscles of the paretic leg and facilitate use-dependent motor learning of locomotor tasks, which might retain longer and partially transfer from treadmill to overground walking, in stroke survivors.

Concurrent ankle-assisted movement, biofeedback, and proprioceptive stimulation reduces lower limb motor impairment and improves gait in persons with stroke.

BACKGROUND: Persons with stroke live with residual sensorimotor impairments in their lower limbs (LL), which affects their gait. PURPOSE: We investigated whether these residual impairments and resulting gait deficits can be reduced through concurrently applied assisted movement, biofeedback, and proprioceptive stimulation. METHODS: A robotic device provided impairment-oriented training to the affected LL of 24 persons with stroke (PwS) with moderate-to-severe LL impairment. Participants were given 22-30 training sessions over 2-3 months. During training, the interventional device cyclically dorsiflexed and plantarflexed the ankle at 5 deg/s through ±15 deg for 30 min while the participant assisted with the imposed movement. Concurrently, participants received visual biofeedback of assistive joint torque or agonist EMG while mechanical vibration was applied to the currently lengthening (i.e. antagonist) tendon. RESULTS: Sensorimotor impairment significantly decreased over the training period, which was sustained over 3 months, based on the Fugl-Meyer Assessment (FMA-LL) (p < .001), modified Ashworth scale in dorsiflexors (p < .05), and an ankle strength test (dorsiflexors and plantarflexors) (p < .05). Balance and gait also improved, based on the Tinetti Performance Oriented Mobility Assessment (POMA) (p < .05). CONCLUSION: Impairment-oriented training using a robotic device capable of applying assisted movement, biofeedback, and proprioceptive stimulation significantly reduces LL impairment and improves gait in moderately-to-severely impaired PwS.

Use of cyproheptadine hydrochloride (HCl) to reduce neuromuscular hypertonicity in stroke survivors: A Randomized Trial: Reducing Hypertonicity in Stroke.

OBJECTIVES: The goal of this study was to examine how the administration and dosing of the anti-serotonergic medication cyproheptadine hydrochloride (HCl) affects involuntary muscle hypertonicity of the spastic and paretic hands of stroke survivors. MATERIALS AND METHODS: A randomized, double-blinded, placebo-controlled longitudinal intervention study was performed as a component of a larger clinical trial. 94 stroke survivors with chronic, severe hand impairment, rated as levels 2 or 3 on the Chedoke-McMaster Stroke Assessment Stage of Hand (CMSA-H), were block randomized to groups receiving doses of cyproheptadine HCl or matched doses of placebo. Doses were increased from 4 mg BID to 8 mg TID over 3 weeks. Outcomes were assessed at baseline and after each of the three weeks of intervention. Primary outcome measure was grip termination time; other measures included muscle strength, spasticity, coactivation of the long finger flexors, and recording of potential adverse effects such as sleepiness and depression. RESULTS: 89 participants (receiving cyproheptadine HCl: 44, receiving placebo: 45) completed the study. The Cyproheptadine group displayed significant reduction in grip termination time, in comparison with the Placebo group (p<0.05). Significant change in the Cyproheptadine group (45% time reduction) was observed after only one week at the 4mg BID dosage. The effect was pronounced for those participants in the Cyproheptadine group with more severe hand impairment (CMSA-H level 2) at baseline. Conversely, no significant effect of Group * Session interaction was observed for spasticity (p=0.6) or coactivation (p=0.53). There were no significant changes in strength (p=0.234) or depression (p=0.441) during the trial. CONCLUSIONS: Use of cyproheptadine HCl was associated with a significant reduction in relaxation time of finger flexor muscles, without adversely affecting voluntary strength, although spasticity and coactivation were unchanged. Decreasing the duration of involuntary flexor activity can facilitate object release and repeated prehensile task performance. REGISTRATION: Clinical Trial number: NCT02418949.

Repeated adaptation and de-adaptation to the pelvis resistance force facilitate retention of motor learning in stroke survivors.

Locomotor adaptation to novel walking patterns induced by external perturbation has been tested to enhance motor learning for improving gait parameters in individuals poststroke. However, little is known regarding whether repeated adaptation and de-adaptation to the externally perturbed walking pattern may facilitate or degrade the retention of locomotor learning. In this study, we examined whether the intermittent adaptation to novel walking patterns elicited by external perturbation induces greater retention of the adapted locomotion in stroke survivors, compared with effects of the continuous adaptation. Fifteen individuals poststroke participated in two experimental conditions consisting of 1) treadmill walking with intermittent (i.e., interspersed 2 intervals of no perturbation) or continuous (no interval) adaptation to externally perturbed walking patterns and 2) overground walking before, immediately, and 10 min after treadmill walking. During the treadmill walking, we applied a laterally pulling force to the pelvis toward the nonparetic side during the stance phase of the paretic leg to disturb weight shifts toward the paretic side. Participants showed improved weight shift toward the paretic side and enhanced muscle activation of hip abductor/adductors immediately after the removal of the pelvis perturbation for both intermittent and continuous conditions (P < 0.05) and showed longer retention of the improved weight shift and enhanced muscle activation for the intermittent condition, which transferred from treadmill to overground walking (P < 0.05). In conclusion, repeated motor adaptation and de-adaptation to the pelvis resistance force during walking may promote the retention of error-based motor learning for improving weight shift toward the paretic side in individuals poststroke.NEW & NOTEWORTHY We examined whether the intermittent versus the continuous adaptation to external perturbation induces greater retention of the adapted locomotion in stroke survivors. We found that participants showed longer retention of the improved weight shift and enhanced muscle activation for the intermittent versus the continuous conditions, suggesting that repeated motor adaptation and de-adaptation to the pelvis perturbation may promote the retention of error-based motor learning for improving weight shift toward the paretic side in individuals poststroke.

Use of an EMG-Controlled Game as a Therapeutic Tool to Retrain Hand Muscle Activation Patterns Following Stroke: A Pilot Study.

BACKGROUND/PURPOSE: To determine the feasibility of training with electromyographically (EMG) controlled games to improve control of muscle activation patterns in stroke survivors. METHODS: Twenty chronic stroke survivors (>6 months) with moderate hand impairment were randomized to train either unilaterally (paretic only) or bilaterally over 9 one-hour training sessions. EMG signals from the unilateral or bilateral limbs controlled a cursor location on a computer screen for gameplay. The EMG muscle activation vector was projected onto the plane defined by the first 2 principal components of the activation workspace for the nonparetic hand. These principal components formed the x- and y-axes of the computer screen. RESULTS: The recruitment goal (n = 20) was met over 9 months, with no screen failure, no attrition, and 97.8% adherence rate. After training, both groups significantly decreased the time to move the cursor to a novel sequence of targets (P = 0.006) by reducing normalized path length of the cursor movement (P = 0.005), and improved the Wolf Motor Function Test (WMFT) quality score (P = 0.01). No significant group difference was observed. No significant change was seen in the WMFT time or Box and Block Test. DISCUSSION/CONCLUSIONS: Stroke survivors could successfully use the EMG-controlled games to train control of muscle activation patterns. While the nonparetic limb EMG was used in this study to create target EMG patterns, the system supports various means for creating target patterns per user desires. Future studies will employ training with the EMG-controlled games in conjunction with functional task practice for a longer intervention duration to improve overall hand function.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A379).

Gait and Balance Outcome Measures Are Responsive in Severely Impaired Individuals Undergoing Inpatient Stroke Rehabilitation.

OBJECTIVE: To investigate whether gait and balance outcome measures in patients with severe gait and balance impairments at admission to inpatient rehabilitation provided additional and meaningful information beyond customary measures. Specifically, this study investigated whether individuals who obtained low scores at admission exhibited improvements that exceeded the established minimal detectable change during inpatient rehabilitation. We also investigated whether gait outcomes would capture changes in function not identified by customary measures. DESIGN: Secondary analysis of a knowledge translation project aimed at increasing the systematic collection of these outcome measures in a poststroke cohort. SETTING: Subacute inpatient rehabilitation facility. PARTICIPANTS: Individuals<2 months poststroke (N=157) with 34-43 with severe deficits including Berg Balance Scale≤5, 10-meter walk test=0 m/s, or 6-minute walk test=0 m. INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: Berg Balance Scale, 10-meter walk test, 6-minute walk test. RESULTS: After 1 week of rehabilitation, 41%-53% of severely impaired individuals had changes above minimal detectable changes in gait and balance outcomes, which increased to 68%-84% at discharge. Across the entire cohort, FIM locomotion scores failed to identify changes in gait function for 35% of participants after 1 week of rehabilitation. CONCLUSIONS: Routine assessment of gait and balance outcome measures in patients with severe deficits early poststroke may be beneficial. These measures were responsive after 1 week of rehabilitation and detected changes not captured by customary measures. Routine use of a standardized gait and balance assessments may provide clinicians with important information to guide clinical decision making.

Applying the Knowledge-to-Action Framework to Implement Gait and Balance Assessments in Inpatient Stroke Rehabilitation.

OBJECTIVES: The overall objectives of this project were to implement and sustain use of a gait assessment battery (GAB) that included the Berg Balance Scale, 10-meter walk test, and 6-minute walk test during inpatient stroke rehabilitation. The study objective was to assess the effect of the study intervention on clinician adherence to the recommendations and its effect on clinician perceptions and the organization. DESIGN: Pre- and post-training intervention study. SETTING: Subacute inpatient rehabilitation facility. PARTICIPANTS: Physical therapists (N=6) and physical therapist assistants (N=2). INTERVENTION: The intervention comprised a bundle of activities, including codeveloping and executing the plan with clinicians and leaders. The multicomponent implementation plan was based on the Knowledge-to-Action Framework and included implementation facilitation, implementation leadership, and a bundle of knowledge translation interventions that targeted barriers. Implementation was an iterative process in which results from one implementation phase informed planning of the next phase. MAIN OUTCOME MEASURES: Clinician administration adherence, surveys of perceptions, and organizational outcomes. RESULTS: Initial adherence to the GAB was 46% and increased to more than 85% after 6 months. These adherence levels remained consistent 48 months after implementation. Clinician perceptions of measure use were initially high (>63%), with significant improvements in knowledge and use of one measure after implementation. CONCLUSIONS: We successfully implemented the assessment battery with high levels of adherence to recommendations, likely because of using the bundle of knowledge translation activities, facilitation, and use of a framework to codevelop the plan. These changes in practice were sustainable, as determined by a 4-year follow-up.

The Value of Rehabilitation Interventions-Integrating Evidence, Clinical Expertise, Critical Assessment, and Patient Needs: A Conference Report.

To understand issues related to the value, outcomes, and cost-effectiveness of rehabilitation interventions, and to explore how scientific evidence, clinical expertise, and patient needs can be integrated, the Rehabilitation Research and Training Center on Developing Optimal Strategies in Exercise and Survival Skills to Increase Health and Function held a State of the Science Symposium on "The Value of Rehabilitation Interventions" at Shirley Ryan AbilityLab in Chicago in 2017. During this conference, 35 invited experts, including individuals with disabilities, professionals, and consumers, explored the topic of the "value" of rehabilitation interventions and discussed their perspectives on the means to integrate best scientific evidence with clinical expertise and patient preferences. This symposium also resulted in the production of several multifaceted articles providing perspectives on the topic of value and how to use evidence to best determine and demonstrate it. These articles comprise this supplement. The present article introduces the key concepts of value, evidence, and knowledge translation in an effort to provide a context for the articles that follow in the supplement.

Characteristics of the severely impaired hand in survivors of stroke with chronic impairments.

BACKGROUND: Diminished sensorimotor control of the hand is one of the most common outcomes following stroke. This hand impairment substantially impacts overall function and quality of life; standard therapy often results in limited improvement. Mechanisms of dysfunction of the severely impaired post-stroke hand are still incompletely understood, thereby impeding the development of new targeted treatments. OBJECTIVE: To identify and determine potential relationships among the mechanisms responsible for hand impairment following stroke. METHODS: This cohort study observed stroke survivors (n = 95) with severe, chronic hand impairment (Chedoke-McMaster Hand score = 2-3). Custom instrumentation created precise perturbations and measured kinematic responses. Muscle activation was recorded through electromyography. Strength, spasticity, muscle relaxation time, and muscle coactivation were quantified. RESULTS: Maximum grip strength in the paretic hand was only 12% of that achieved by the nonparetic hand, and only 6 of 95 participants were able to produce any net extension force. Despite force deficits, spastic reflex response of the finger flexor evoked by imposed stretch averaged 90.1 ± 26.8% of maximum voluntary activation, relaxation time averaged 3.8 ± 0.8 seconds, and coactivation during voluntary extension exceeded 30% of maximum contraction, thereby resulting in substantial net flexion. Surprisingly, these hypertonicity measures were not significantly correlated with each other. CONCLUSIONS: Survivors of severe, chronic hemiparetic stroke experience profound weakness of both flexion and extension that arises from increased involuntary antagonist activation and decreased voluntary activation. The lack of correlation amongst hypertonicity measures suggests that these phenomena may arise from multiple, potentially independent mechanisms that could require different treatments.

Enhanced error facilitates motor learning in weight shift and increases use of the paretic leg during walking at chronic stage after stroke.

The purpose of this study was to determine whether the application of lateral pelvis pulling force toward the non-paretic side during the stance phase of the paretic leg would enhance forced use of the paretic leg and increase weight shift toward the paretic side in stroke survivors. Eleven chronic stroke survivors participated in two experimental sessions, which consisted of (1) treadmill walking with the application of "pelvis resistance" or "pelvis assistance" and (2) overground walking. During the treadmill walking, the laterally pulling force was applied during the stance phase of the paretic leg toward the non-paretic side for the "pelvis resistance" condition or toward the paretic side for the "pelvis assistance" condition during the stance phase of the paretic leg. After force release, the "pelvis resistance" condition exhibited greater enhancement in muscle activation of hip ABD, ADD, and SOL and greater improvement in lateral weight shift toward the paretic side, compared with the effect of the "pelvis assistance" condition (P < 0.03). This improved lateral weight shift was associated with the enhanced muscle activation of hip ABD and ADD (R2 = 0.67, P = 0.01). The pelvis resistance condition also improved overground walking speed and stance phase symmetry when measured 10 min after the treadmill walking (P = 0.004). In conclusion, applying pelvis resistance forces to increase error signals may facilitate motor learning of weight shift toward the paretic side and enhance use of the paretic leg in chronic stroke survivors. Results from this study may be utilized to develop an intervention approach to improve walking in stroke survivors.

Clinical Performance Measures for Stroke Rehabilitation: Performance Measures From the American Heart Association/American Stroke Association.

The American Heart Association/American Stroke Association released the adult stroke rehabilitation and recovery guidelines in 2016. A working group of stroke rehabilitation experts reviewed these guidelines and identified a subset of recommendations that were deemed suitable for creating performance measures. These 13 performance measures are reported here and contain inclusion and exclusion criteria to allow calculation of rates of compliance in a variety of settings ranging from acute hospital care to postacute care and care in the home and outpatient setting.

Gradual adaptation to pelvis perturbation during walking reinforces motor learning of weight shift toward the paretic side in individuals post-stroke.

The purpose of this study was to determine whether the gradual versus abrupt adaptation to lateral pelvis assistance force improves weight shift toward the paretic side and enhance forced use of the paretic leg during walking. Sixteen individuals who had sustained a hemispheric stroke participated in two experimental sessions, which consisted of (1) treadmill walking with the application of lateral pelvis assistance force (gradual vs. abrupt condition) and (2) overground walking. In the "gradual" condition, during treadmill walking, the assistance force was gradually increased from 0 to 100% of the predetermined force step by step. In the abrupt condition, the force was applied at 100% of the predetermined force throughout treadmill walking. Participants exhibited significant improvements in hip abductor and adductor, ankle dorsiflexor, and knee extensor muscle activities, weight shift toward the paretic side, and overground walking speed in the gradual condition (P < 0.05), but showed no significant changes in the abrupt condition (P > 0.20). Changes in weight shift toward the paretic side were statistically different between conditions (P < 0.001), although changes in muscle activities were not (P > 0.11). In the gradual condition, the error amplitude was proportional to the improvement in weight shift during the late post-adaptation (R2 = 0.32, P = 0.03), but not in the abrupt condition (R2 = 0.001, P = 0.93). In conclusion, the "gradual adaptation" inducing "small errors" during constraint-induced walking may improve weight shift and enhance forced use of the paretic leg in individuals post-stroke. Applying gradual pelvis assistance force during walking may be used as an intervention strategy to improve walking in individuals post-stroke.

Increased motor variability facilitates motor learning in weight shift toward the paretic side during walking in individuals post-stroke.

The purpose of this study was to determine whether applying "varied" versus constant pelvis assistance force mediolaterally toward the paretic side of stroke survivors during walking would result in short-term improvement in weight shift toward the paretic side. Twelve individuals post-stroke (60.4 ± 6.2 years; gait speed: 0.53 ± 0.19 m/s) were tested under two conditions (varied vs. constant). Each condition was conducted in a single separate session, which consisted of (a) treadmill walking with no assistance force for 1 min (baseline), pelvis assistance toward the paretic side for 9 min (adaptation), and then no force for additional 1 min (post-adaptation), and (b) overground walking. In the "varied" condition, the magnitude of force was randomly changed across steps between 30% and 100% of the predetermined amount. In the abrupt condition, the magnitude of force was kept constant at 100% of the predetermined amount. Participants exhibited greater improvements in weight shift toward the paretic side (p < 0.01) and in muscle activity of plantar flexors and hip adductors of the paretic leg (p = 0.02) from baseline to late post-adaptation period for the varied condition than for the constant condition. Motor variability of the peak pelvis displacement at baseline was correlated with improvement in weight shift toward the paretic side after training for the varied (R2  = 0.64, p = 0.01) and the constant condition (R2  = 0.39, p = 0.03). These findings suggest that increased motor variability, induced by applying the varied pelvis assistance, may facilitate motor learning in weight shift and gait symmetry during walking in individuals post-stroke.

Characterization of Motor-Evoked Responses Obtained with Transcutaneous Electrical Spinal Stimulation from the Lower-Limb Muscles after Stroke.

An increasing number of studies suggests that a novel neuromodulation technique targeting the spinal circuitry enhances gait rehabilitation, but research on its application to stroke survivors is limited. Therefore, we investigated the characteristics of spinal motor-evoked responses (sMERs) from lower-limb muscles obtained by transcutaneous spinal cord stimulation (tSCS) after stroke compared to age-matched and younger controls without stroke. Thirty participants (ten stroke survivors, ten age-matched controls, and ten younger controls) completed the study. By using tSCS applied between the L1 and L2 vertebral levels, we compared sMER characteristics (resting motor threshold (RMT), slope of the recruitment curve, and latency) of the tibialis anterior (TA) and medial gastrocnemius (MG) muscles among groups. A single pulse of stimulation was delivered in 5 mA increments, increasing from 5 mA to 250 mA or until the subjects reached their maximum tolerance. The stroke group had an increased RMT (27-51%) compared to both age-matched (TA: p = 0.032; MG: p = 0.005) and younger controls (TA: p < 0.001; MG: p<0.001). For the TA muscle, the paretic side demonstrated a 13% increased latency compared to the non-paretic side in the stroke group (p = 0.010). Age-matched controls also exhibited an increased RMT compared to younger controls (TA: p = 0.002; MG: p = 0.007), suggesting that altered sMER characteristics present in stroke survivors may result from both stroke and normal aging. This observation may provide implications for altered spinal motor output after stroke and demonstrates the feasibility of using sMER characteristics as an assessment after stroke.

Intense Arm Rehabilitation Therapy Improves the Modified Rankin Scale Score: Association Between Gains in Impairment and Function.

OBJECTIVE: To evaluate the effect of intensive rehabilitation on the modified Rankin Scale (mRS), a measure of activities limitation commonly used in acute stroke studies, and to define the specific changes in body structure/function (motor impairment) most related to mRS gains. METHODS: Patients were enrolled >90 days poststroke. Each was evaluated before and 30 days after a 6-week course of daily rehabilitation targeting the arm. Activity gains, measured using the mRS, were examined and compared to body structure/function gains, measured using the Fugl-Meyer (FM) motor scale. Additional analyses examined whether activity gains were more strongly related to specific body structure/function gains. RESULTS: At baseline (160 ± 48 days poststroke), patients (n = 77) had median mRS score of 3 (interquartile range, 2-3), decreasing to 2 [2-3] 30 days posttherapy (p < 0.0001). Similarly, the proportion of patients with mRS score ≤2 increased from 46.8% at baseline to 66.2% at 30 days posttherapy (p = 0.015). These findings were accounted for by the mRS score decreasing in 24 (31.2%) patients. Patients with a treatment-related mRS score improvement, compared to those without, had similar overall motor gains (change in total FM score, p = 0.63). In exploratory analysis, improvement in several specific motor impairments, such as finger flexion and wrist circumduction, was significantly associated with higher likelihood of mRS decrease. CONCLUSIONS: Intensive arm motor therapy is associated with improved mRS in a substantial fraction (31.2%) of patients. Exploratory analysis suggests specific motor impairments that might underlie this finding and may be optimal targets for rehabilitation therapies that aim to reduce activities limitations. CLINICAL TRIAL: Clinicaltrials.gov identifier: NCT02360488. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that for patients >90 days poststroke with persistent arm motor deficits, intensive arm motor therapy improved mRS in a substantial fraction (31.2%) of patients.