Motor rehabilitation after stroke, traumatic brain, and spinal cord injury: common denominators within recent clinical trials

Comparative Efficacy of High-Intensity Training Versus Conventional Training in Individuals With Chronic Traumatic Brain Injury: A Pilot Randomized Controlled Study

Numerous studies have evaluated the efficacy of interventions to improve locomotion after acute-onset brain injury, although most focus on patients with stroke, with less attention toward traumatic brain injury (TBI). For example, a number of studies in patients post-stroke have evaluated the effects of high-intensity training (HIT) attempting to maximize stepping practice, while no studies have attempted this intervention in patients with TBI. The purpose of this blinded-assessor randomized trial was to evaluate the effects of HIT focused on stepping practice versus conventional training on walking and secondary outcomes in individuals with TBI. Using a crossover design, ambulatory participants with TBI >6-months duration performed HIT focused on stepping in variable contexts (overground, treadmill, stairs) or conventional training for up to 15 sessions over five weeks, with interventions alternated >4 weeks later. HIT focused on maximizing stepping practice while trying to achieve higher cardiovascular intensities (>70% heart rate reserve), while conventional training focused on impairment-based and functional exercises with no restrictions on intensities achieved. Greater increases in 6-min walk test and peak treadmill speed during graded exercise testing were observed after HIT versus conventional training, with moderate associations between differences in stepping practice and outcomes. Greater gains were also observed in estimates of aerobic capacity and efficiency after HIT, with additional improvements in selected cognitive assessments. The present study suggests that the amount and intensity of stepping practice may be important determinants of improved locomotor outcomes in patients with chronic TBI, with possible secondary benefits on aerobic capacity/efficiency and cognition. Clinical Trial Registration-URL: https://clinicaltrials.gov/; Unique Identifier: NCT04503473.

Neuro-Rehabilitation Therapy with T-FLEX Ankle Exoskeleton and Serious Games: A Case Study

Acquired Brain Injury (ABI) causes permanent disabilities, such as foot drop. This condition affects the gait pattern, increasing the metabolic cost and risk of falling. Robotics with serious games has shown promising results in the gait rehabilitation context. This paper aims to analyze the effects of using the T-FLEX exoskeleton with (1) Automated Therapy (AT) and (2) Serious Game Therapy (SGT) in two ABI patients. Each participant completed six assisted sessions for each strategy. Results showed that AT increases the user-robot interaction torque by 10% for the first patient and 70% for the second patient, and SGT decreases by 5% for both patients. This way, SGT required the patient to generate torque to execute the ankle movement, while AT did the opposite, resulting in greater device assistance. In the functional assessment, SGT induced variations greater than 50% for the paretic ankle and knee's range of motion (ROM), indicating a potential for motor recovery. Thus, SGT led to improved ankle control and increased gait speed compared to AT. These findings suggest that SGT may be an effective rehabilitation strategy for ABI-related foot drop patients.

The Effects of Stroke and Stroke Gait Rehabilitation on Behavioral and Neurophysiological Outcomes:: Challenges and Opportunities for Future Research

Stroke continues to be a leading cause of adult disability, contributing to immense healthcare costs. Even after discharge from rehabilitation, post-stroke individuals continue to have persistent gait impairments, which in turn adversely affect functional mobility and quality of life. Multiple factors, including biomechanics, energy cost, psychosocial variables, as well as the physiological function of corticospinal neural pathways influence stroke gait function and training-induced gait improvements. As a step toward addressing this challenge, the objective of the current perspective paper is to outline knowledge gaps pertinent to the measurement and retraining of stroke gait dysfunction. The paper also has recommendations for future research directions to address important knowledge gaps, especially related to the measurement and rehabilitation-induced modulation of biomechanical and neural processes underlying stroke gait dysfunction. We posit that there is a need for leveraging emerging technologies to develop innovative, comprehensive, methods to measure gait patterns quantitatively, to provide clinicians with objective measure of gait quality that can supplement conventional clinical outcomes of walking function. Additionally, we posit that there is a need for more research on how the stroke lesion affects multiple parts of the nervous system, and to understand the neuroplasticity correlates of gait training and gait recovery. Multi-modal clinical research studies that can combine clinical, biomechanical, neural, and computational modeling data provide promise for gaining new information about stroke gait dysfunction as well as the multitude of factors affecting recovery and treatment response in people with post-stroke hemiparesis.

A Novel Neurorehabilitation Approach for Neural Plasticity Overstimulation and Reorganization in Patients with Neurological Disorders

Neurological disorders are those that are associated with impairments in the nervous system. These impairments affect the patient’s activities of daily living. Recently, many advanced modalities have been used in the rehabilitation field to treat various neurological impairments. However, many of these modalities are available only in clinics, and some are expensive. Most patients with neurological disorders have difficulty reaching clinics. This review was designed to establish a new neurorehabilitation approach based on the scientific way to improve patients’ functional recovery following neurological disorders in clinics or at home. The human brain is a network, an intricate, integrated system that coordinates operations among billions of units. In fact, grey matter contains most of the neuronal cell bodies. It includes the brain and the spinal cord areas involved in muscle control, sensory perception, memory, emotions, decision-making, and self-control. Consequently, patients’ functional ability results from complex interactions among various brain and spinal cord areas and neuromuscular systems. While white matter fibers connect numerous brain areas, stimulating or improving non-motor symptoms, such as motivation, cognitive, and sensory symptoms besides motor symptoms may enhance functional recovery in patients with neurological disorders. The basic principles of the current treatment approach are established based on brain connectivity. Using motor, sensory, motivation, and cognitive (MSMC) interventions during rehabilitation may promote neural plasticity and maximize functional recovery in patients with neurological disorders. Experimental studies are strongly needed to verify our theories and hypothesis.

Low-level voluntary input enhances corticospinal excitability during ankle dorsiflexion neuromuscular electrical stimulation in healthy young adults

Previous evidence indicated that interventions with combined neuromuscular electrical stimulation (NMES) and voluntary muscle contractions could have superior effects on corticospinal excitability when the produced total force is larger than each single intervention. However, it is unclear whether the superior effects exist when the produced force is matched between the interventions. Ten able-bodied individuals performed three intervention sessions on separate days: (i) NMES-tibialis anterior (TA) stimulation; (ii) NMES+VOL-TA stimulation combined with voluntary ankle dorsiflexion; (iii) VOL-voluntary ankle dorsiflexion. Each intervention was exerted at the same total output of 20% of maximal force and applied intermittently (5 s ON / 19 s OFF) for 16 min. Motor evoked potentials (MEP) of the right TA and soleus muscles and maximum motor response (Mmax) of the common peroneal nerve were assessed: before, during, and for 30 min after each intervention. Additionally, the ankle dorsiflexion force-matching task was evaluated before and after each intervention. Consequently, the TA MEP/Mmax during NMES+VOL and VOL sessions were significantly facilitated immediately after the interventions started until the interventions were over. Compared to NMES, larger facilitation was observed during NMES+VOL and VOL sessions, but no difference was found between them. Motor control was not affected by any interventions. Although superior combined effects were not shown compared to voluntary contractions alone, low-level voluntary contractions combined with NMES resulted in facilitated corticospinal excitability compared to NMES alone. This suggests that the voluntary drive could improve the effects of NMES even during low-level contractions, even if motor control is not affected.

Music Therapy Supports Children with Neurological Diseases during Physical Therapy Interventions

Recent research found evidence supporting music therapy for children with neurological diseases during their hospitalized neurological early rehabilitation to promote their development during physical therapy. We hypothesized that live music therapy might improve vital signs during a physical therapy session. Seventeen children received live music therapy during the physical therapy session twice a week. Two more physical therapy sessions per week were held without music therapy. Heart rate, respiratory rate and oxygen saturation were recorded from 15 min before to 15 min after the therapy sessions. Physical therapy interventions showed changes in heart rate, respiratory rate and oxygen saturation between, before and after the sessions with or without music therapy. Live music therapy was effective for the vital signs during the intervention. We observed significantly lower heart and respiratory rates and higher oxygen saturation during physical therapy intervention with live music therapy in general (mean differences −8.0 beats per min; −0.8 breaths per min and +0.6%). When physical therapy was applied without music therapy children’s heart rates increased by 8.5 beats per min and respiratory rates increased by 1.0 breaths per min. Live music therapy leads to a decrease in heart and respiratory rates and an increase in oxygen saturation in children with neurological diseases during physical therapy with live music therapy. Music therapy supports the children in physical therapy interventions during their hospitalization.

Upper Limb Motor Improvement after Traumatic Brain Injury: Systematic Review of Interventions

BACKGROUND

Traumatic brain injury (TBI) is a leading cause of adult morbidity and mortality. Individuals with 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 issues. There is limited understanding on the use of interventions for upper limb (UL) motor improvements in this population.

OBJECTIVE

We examined the evidence regarding the effectiveness of different interventions to augment UL motor improvement after a TBI.

METHODS

We systematically examined the evidence published in English from 1990-2020. The modified Downs 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.

RESULTS

Twenty-three studies were retrieved. Study quality was excellent (n = 1), good (n = 5) or fair (n = 17). Interventions used included strategies to decrease muscle tone (n = 6), constraint induced movement therapy (n = 4), virtual reality gaming (n = 5), non-invasive stimulation (n = 3), arm motor ability training (n = 1), stem cell transplant (n = 1), task-oriented training (n = 2), and feedback provision (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 (MAL). Effect sizes for majority of the interventions ranged from medium (.5-.79) to large (≥.8). Only ten studies included retention testing.

CONCLUSION

There is preliminary evidence that using some interventions may enhance UL motor improvement after a TBI. Answers to emergent questions can help select the most appropriate interventions in this population.

Usability, functionality, and efficacy of a custom myoelectric elbow-wrist-hand orthosis to assist elbow function in individuals with stroke

Introduction

After stroke, upper limb impairment affects independent performance of activities of daily living. We evaluated the usability, functionality, and efficacy of a myoelectric elbow-wrist-hand orthosis to provide support, limit unsafe motion, and enhance the functional motion of paralyzed or weak upper limbs.

Methods

Individuals with stroke participated in a single-session study to evaluate the device. Ability to activate the device was tested in supported and unsupported shoulder position, as well as the elbow range of motion, ability to maintain elbow position, and ability to lift and hold a range of weights while using the device.

Results

No adverse events were reported. 71% of users were able to operate the device in all three active myoelectric activation modes (Biceps, Triceps, Dual) during testing. Users were able to hold a range of wrist weights (0.5–2 lbs) for 10–120 seconds, with the largest percentage of participants able to hold weights with the device in Biceps Mode.

Conclusions

The myoelectric elbow-wrist-hand orthosis improved range of motion during use and was efficacious at remediating upper extremity impairment after stroke. All users could operate the device in at least one mode, and most could lift and hold weights representative of some everyday objects using the device.

Intensity of usual care physical therapy during inpatient rehabilitation for people with neurologic diagnoses

BACKGROUND

Early, intense rehabilitation is essential to promote recovery after stroke, spinal cord injury (SCI), and traumatic brain injury (TBI). However, intensity of usual care rehabilitation interventions during inpatient rehabilitation are poorly characterized.

OBJECTIVE

To describe the intensity of usual care rehabilitation interventions completed during the subacute phase of recovery from neurologic injury.

DESIGN

Observational.

SETTING

Inpatient rehabilitation facility.

INTERVENTIONS

Twenty-two usual care physical therapy interventions were grouped into six categories: gait (four activities), functional (two), strengthening (four), aerobic (six), balance (four), and wheelchair (two).

PATIENTS

Patients admitted to inpatient rehabilitation with a primary diagnosis of stroke, SCI or TBI within 6 months of injury.

MAIN OUTCOME MEASURE(S)

Cardiovascular intensity (physiological and perceived) was recorded during rehabilitation activity sessions. Physiological intensity was assessed by heart rate reserve (HRR) via a Polar A370 Fitness Watch and characterized as very light (<30%), light (30-39%), moderate (40-59%), vigorous (60-89%), and near maximal (≥90%). Perceived intensity was assessed using the Rating of Perceived Exertion scale.

RESULTS

Patients (stroke n = 16 [number of activity sessions = 388/average session duration = 15.1 min]; SCI n = 15 [299/27.3 min]; TBI n = 15 [340/13.4 min]) participated. For patients with stroke, moderate-to-vigorous HRR was attained between 42% (aerobic exercise) to 55% (wheelchair propulsion) of activity sessions. For patients with SCI, moderate-to-vigorous HRR was attained between 29% (strength training) to 46% (gait training) of activity sessions. For patients with TBI, moderate-to-vigorous HRR was attained between 29% (balance activities) to 47% (gait training) of activity sessions. Associations between HRR and rate of perceived exertion were very weak across stroke (r = 0.12), SCI (r = 0.18), and TBI (r = 0.27).

CONCLUSIONS

Patients with stroke, SCI, and TBI undergoing inpatient rehabilitation achieve moderate-to-vigorous intensity during some usual care activities such as gait training. Patient perception of intensity was dissimilar to physiological response.

Clinical Practice Guideline to Improve Locomotor Function Following Chronic Stroke, Incomplete Spinal Cord Injury, and Brain Injury

BACKGROUND

Individuals with acute-onset central nervous system (CNS) injury, including stroke, motor incomplete spinal cord injury, or traumatic brain injury, often experience lasting locomotor deficits, as quantified by decreases in gait speed and distance walked over a specific duration (timed distance). The goal of the present clinical practice guideline was to delineate the relative efficacy of various interventions to improve walking speed and timed distance in ambulatory individuals greater than 6 months following these specific diagnoses.

METHODS

A systematic review of the literature published between 1995 and 2016 was performed in 4 databases for randomized controlled clinical trials focused on these specific patient populations, at least 6 months postinjury and with specific outcomes of walking speed and timed distance. For all studies, specific parameters of training interventions including frequency, intensity, time, and type were detailed as possible. Recommendations were determined on the basis of the strength of the evidence and the potential harm, risks, or costs of providing a specific training paradigm, particularly when another intervention may be available and can provide greater benefit.

RESULTS

Strong evidence indicates that clinicians should offer walking training at moderate to high intensities or virtual reality-based training to ambulatory individuals greater than 6 months following acute-onset CNS injury to improve walking speed or distance. In contrast, weak evidence suggests that strength training, circuit (ie, combined) training or cycling training at moderate to high intensities, and virtual reality-based balance training may improve walking speed and distance in these patient groups. Finally, strong evidence suggests that body weight-supported treadmill training, robotic-assisted training, or sitting/standing balance training without virtual reality should not be performed to improve walking speed or distance in ambulatory individuals greater than 6 months following acute-onset CNS injury to improve walking speed or distance.

DISCUSSION

The collective findings suggest that large amounts of task-specific (ie, locomotor) practice may be critical for improvements in walking function, although only at higher cardiovascular intensities or with augmented feedback to increase patient's engagement. Lower-intensity walking interventions or impairment-based training strategies demonstrated equivocal or limited efficacy.

LIMITATIONS

As walking speed and distance were primary outcomes, the research participants included in the studies walked without substantial physical assistance. This guideline may not apply to patients with limited ambulatory function, where provision of walking training may require substantial physical assistance.

SUMMARY

The guideline suggests that task-specific walking training should be performed to improve walking speed and distance in those with acute-onset CNS injury although only at higher intensities or with augmented feedback. Future studies should clarify the potential utility of specific training parameters that lead to improved walking speed and distance in these populations in both chronic and subacute stages following injury.

DISCLAIMER

These recommendations are intended as a guide for clinicians to optimize rehabilitation outcomes for persons with chronic stroke, incomplete spinal cord injury, and traumatic brain injury to improve walking speed and distance.

Neurostimulation and Reach-to-Grasp Function Recovery Following Acquired Brain Injury: Insight From Pre-clinical Rodent Models and Human Applications

Reach-to-grasp is an evolutionarily conserved motor function that is adversely impacted following stroke and traumatic brain injury (TBI). Non-invasive brain stimulation (NIBS) methods, such as transcranial magnetic stimulation and transcranial direct current stimulation, are promising tools that could enhance functional recovery of reach-to-grasp post-brain injury. Though the rodent literature provides a causal understanding of post-injury recovery mechanisms, it has had a limited impact on NIBS protocols in human research. The high degree of homology in reach-to-grasp circuitry between humans and rodents further implies that the application of NIBS to brain injury could be better informed by findings from pre-clinical rodent models and neurorehabilitation research. Here, we provide an overview of the advantages and limitations of using rodent models to advance our current understanding of human reach-to-grasp function, cortical circuitry, and reorganization. We propose that a cross-species comparison of reach-to-grasp recovery could provide a mechanistic framework for clinically efficacious NIBS treatments that could elicit better functional outcomes for patients.

Regional estimates of cortical thickness in brain areas involved in control of surgically restored limb movement in patients with tetraplegia

Context/Objective: Spinal cord injury (SCI) causes atrophy of brain regions linked to motor function. We aimed to estimate cortical thickness in brain regions that control surgically restored limb movement in individuals with tetraplegia. Design: Cross-sectional study. Setting: Sahlgrenska University hospital, Gothenburg, Sweden. Participants: Six individuals with tetraplegia who had undergone surgical restoration of grip function by surgical transfer of one elbow flexor (brachioradialis), to the paralyzed thumb flexor (flexor pollicis longus). All subjects were males, with a SCI at the C6 or C7 level, and a mean age of 40 years (range = 31-48). The average number of years elapsed since the SCI was 13 (range = 6-26). Outcome measures: We used structural magnetic resonance imaging (MRI) to estimate the thickness of selected motor cortices and compared these measurements to those of six matched control subjects. The pinch grip control area was defined in a previous functional MRI study. Results: Compared to controls, the cortical thickness in the functionally defined pinch grip control area was not significantly reduced (P = 0.591), and thickness showed a non-significant but positive correlation with years since surgery in the individuals with tetraplegia. In contrast, the anatomically defined primary motor cortex as a whole exhibited substantial atrophy (P = 0.013), with a weak negative correlation with years since surgery. Conclusion: Individuals with tetraplegia do not seem to have reduced cortical thickness in brain regions involved in control of surgically restored limb movement. However, the studied sample is very small and further studies with larger samples are required to establish these findings.

Combinational Approach of Genetic SHP-1 Suppression and Voluntary Exercise Promotes Corticospinal Tract Sprouting and Motor Recovery Following Brain Injury

Background. Brain injury often causes severe motor dysfunction, leading to difficulties with living a self-reliant social life. Injured neural circuits must be reconstructed to restore functions, but the adult brain is limited in its ability to restore neuronal connections. The combination of molecular targeting, which enhances neural plasticity, and rehabilitative motor exercise is an important therapeutic approach to promote neuronal rewiring in the spared circuits and motor recovery. Objective. We tested whether genetic reduction of Src homology 2-containing phosphatase-1 (SHP-1), an inhibitor of brain-derived neurotrophic factor (BDNF)/tropomyosin receptor kinase B (TrkB) signaling, has synergistic effects with rehabilitative training to promote reorganization of motor circuits and functional recovery in a mouse model of brain injury. Methods. Rewiring of the corticospinal circuit was examined using neuronal tracers following unilateral cortical injury in control mice and in Shp-1 mutant mice subjected to voluntary exercise. Recovery of motor functions was assessed using motor behavior tests. Results. We found that rehabilitative exercise decreased SHP-1 and increased BDNF and TrkB expression in the contralesional motor cortex after the injury. Genetic reduction of SHP-1 and voluntary exercise significantly increased sprouting of corticospinal tract axons and enhanced motor recovery in the impaired forelimb. Conclusions. Our data demonstrate that combining voluntary exercise and SHP-1 suppression promotes motor recovery and neural circuit reorganization after brain injury.

A randomized controlled study incorporating an electromechanical gait machine, the Hybrid Assistive Limb, in gait training of patients with severe limitations in walking in the subacute phase after stroke

Early onset, intensive and repetitive, gait training may improve outcome after stroke but for patients with severe limitations in walking, rehabilitation is a challenge. The Hybrid Assistive Limb (HAL) is a gait machine that captures voluntary actions and support gait motions. Previous studies of HAL indicate beneficial effects on walking, but these results need to be confirmed in blinded, randomized controlled studies. This study aimed to explore effects of incorporating gait training with HAL as part of an inpatient rehabilitation program after stroke. Thirty-two subacute stroke patients with severe limitations in walking were randomized to incorporated HAL training (4 days/week for 4 weeks) or conventional gait training only. Blinded assessments were carried out at baseline, after the intervention, and at 6 months post stroke. The primary outcome was walking independence according to the Functional Ambulation Categories. Secondary outcomes were the Fugl-Meyer Assessment, 2-Minute Walk Test, Berg Balance Scale, and the Barthel Index. No significant between-group differences were found regarding any primary or secondary outcomes. At 6 months, two thirds of all patients were independent in walking. Prediction of independent walking at 6 months was not influenced by treatment group, but by age (OR 0.848, CI 0.719-0.998, p = 0.048). This study found no difference between groups for any outcomes despite the extra resources required for the HAL training, but highlights the substantial improvements in walking seen when evidence-based rehabilitation is provided to patients, with severe limitations in walking in the subacute stage after stroke. In future studies potential subgroups of patients who will benefit the most from electromechanically-assisted gait training should be explored.

White Paper: Movement System Diagnoses in Neurologic Physical Therapy

BACKGROUND AND PURPOSE

The APTA recently established a vision for physical therapists to transform society by optimizing movement to promote health and wellness, mitigate impairments, and prevent disability. An important element of this vision entails the integration of the movement system into the profession, and necessitates the development of movement system diagnoses by physical therapists. At this point in time, the profession as a whole has not agreed upon diagnostic classifications or guidelines to assist in developing movement system diagnoses that will consistently capture an individual's movement problems. We propose that, going forward, diagnostic classifications of movement system problems need to be developed, tested, and validated. The Academy of Neurologic Physical Therapy's Movement System Task Force was convened to address these issues with respect to management of movement system problems in patients with neurologic conditions. The purpose of this article is to report on the work and recommendations of the Task Force.

SUMMARY OF KEY FINDINGS

The Task Force identified 4 essential elements necessary to develop and implement movement system diagnoses for patients with primarily neurologic involvement from existing movement system classifications. The Task Force considered the potential impact of using movement system diagnoses on clinical practice, education and, research. Recommendations were developed and provided recommendations for potential next steps to broaden this discussion and foster the development of movement system diagnostic classifications.

RECOMMENDATIONS FOR CLINICAL PRACTICE

The Task Force proposes that diagnostic classifications of movement system problems need to be developed, tested, and validated with the long-range goal to reach consensus on and adoption of a movement system diagnostic framework for clients with neurologic injury or disease states.Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A198).

High-Intensity Variable Stepping Training in Patients With Motor Incomplete Spinal Cord Injury: A Case Series

BACKGROUND AND PURPOSE

Previous data suggest that large amounts of high-intensity stepping training in variable contexts (tasks and environments) may improve locomotor function, aerobic capacity, and treadmill gait kinematics in individuals poststroke. Whether similar training strategies are tolerated and efficacious for patients with other acute-onset neurological diagnoses, such as motor incomplete spinal cord injury (iSCI), is unknown. Individuals with iSCI potentially have greater bilateral impairments. This case series evaluated the feasibility and preliminary short- and long-term efficacy of high-intensity variable stepping practice in ambulatory participants for more than 1 year post-iSCI.

CASE SERIES DESCRIPTION

Four participants with iSCI (neurological levels C5-T3) completed up to 40 one-hour sessions over 3 to 4 months. Stepping training in variable contexts was performed at up to 85% maximum predicted heart rate, with feasibility measures of patient tolerance, total steps/session, and intensity of training. Clinical measures of locomotor function, balance, peak metabolic capacity, and gait kinematics during graded treadmill assessments were performed at baseline and posttraining, with more than 1-year follow-up.

OUTCOMES

Participants completed 24 to 40 sessions over 8 to 15 weeks, averaging 2222 ± 653 steps per session, with primary adverse events of fatigue and muscle soreness. Modest improvements in locomotor capacity where observed at posttraining, with variable changes in lower extremity kinematics during treadmill walking.

DISCUSSION

High-intensity, variable stepping training was feasible and tolerated by participants with iSCI although only modest gains in gait function or quality were observed. The utility of this intervention in patients with more profound impairments may be limited.Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A200).

Adjusting Assistance Commensurates with Patient Effort During Robot-Assisted Upper Limb Training for a Patient with Spasticity After Cervical Spinal Cord Injury: A Case Report

Limited evidence is available on optimal patient effort and degree of assistance to achieve preferable changes during robot-assisted training (RAT) for spinal cord injury (SCI) patients with spasticity. To investigate the relationship between patient effort and robotic assistance, we performed training using an electromyography-based robotic assistance device (HAL-SJ) in an SCI patient at multiple settings adjusted to patient effort. In this exploratory study, we report immediate change in muscle contraction patterns, patient effort, and spasticity in a 64-year-old man, diagnosed with cervical SCI and with American Spinal Injury Association Impairment Scale C level and C4 neurological level, who underwent RAT using HAL-SJ from post-injury day 403. Three patient effort conditions (comfortable, somewhat hard, and no-effort) by adjusting HAL-SJ’s assists were set for each training session. Degree of effort during flexion and extension exercise was assessed by visual analog scale, muscle contraction pattern by electromyography, modified Ashworth scale, and maximum elbow extension and flexion torques, immediately before and after each training session, without HAL-SJ. The amount of effort during training with the HAL-SJ at each session was evaluated. The degree of effort during training can be set to three effort conditions as we intended by adjusting HAL-SJ. In sessions other than the no-effort setting, spasticity improved, and the level of effort was reduced immediately after training. Spasticity did not decrease in the training session using HAL-SJ with the no-effort setting, but co-contraction further increased during extension after training. Extension torque was unchanged in all sessions, and flexion torque decreased in all sessions. When performing upper-limb training with HAL-SJ in this SCI patient, the level of assistance with some effort may reduce spasticity and too strong assistance may increase co-contraction. Sometimes, a patient’s effort may be seemingly unmeasurable; hence, the degree of patient effort should be further measured.

Exosomes in Acquired Neurological Disorders: New Insights into Pathophysiology and Treatment

Exosomes are endogenous nanovesicles that play critical roles in intercellular signaling by conveying functional genetic information and proteins between cells. Exosomes readily cross the blood-brain barrier and have promise as therapeutic delivery vehicles that have the potential to specifically deliver molecules to the central nervous system (CNS). This unique feature also makes exosomes attractive as biomarkers in diagnostics, prognostics, and therapeutics in the context of multiple significant public health conditions, including acquired neurological disorders. The purpose of this review is to summarize the state of the science surrounding the relevance of extracellular vesicles (EVs), particularly exosomes, to acquire neurological disorders, specifically traumatic brain injury (TBI), spinal cord injury (SCI), and ischemic stroke. In total, ten research articles were identified that examined exosomes in the context of TBI, SCI, or stroke; these manuscripts were reviewed and synthesized to further understand the current role of exosomes in the context of acquired neurological disorders. Of the ten published studies, four focused exclusively on TBI, one on both TBI and SCI, and five on ischemic stroke; notably, eight of the ten studies were limited to pre-clinical samples. The present review is the first to discuss the current body of knowledge surrounding the role of exosomes in the pathophysiology, diagnosis, and prognosis, as well as promising therapeutic strategies in TBI, SCI, and stroke research.

Robot-assisted upper extremity rehabilitation for cervical spinal cord injuries: a systematic scoping review

Abstact Purpose: To provide an overview of the feasibility and outcomes of robotic-assisted upper extremity training for individuals with cervical spinal cord injury (SCI), and to identify gaps in current research and articulate future research directions.

MATERIALS AND METHODS

A systematic search was conducted using Medline, Embase, PsycINFO, CCTR, CDSR, CINAHL and PubMed on June 7, 2017. Search terms included 3 themes: (1) robotics; (2) SCI; (3) upper extremity. Studies using robots for upper extremity rehabilitation among individuals with cervical SCI were included. Identified articles were independently reviewed by two researchers and compared to pre-specified criteria. Disagreements regarding article inclusion were resolved through discussion. The modified Downs and Black checklist was used to assess article quality. Participant characteristics, study and intervention details, training outcomes, robot features, study limitations and recommendations for future studies were abstracted from included articles.

RESULTS

Twelve articles (one randomized clinical trial, six case series, five case studies) met the inclusion criteria. Five robots were exoskeletons and three were end-effectors. Sample sizes ranged from 1 to 17 subjects. Articles had variable quality, with quality scores ranging from 8 to 20. Studies had a low internal validity primarily from lack of blinding or a control group. Individuals with mild-moderate impairments showed the greatest improvements on body structure/function and performance-level measures. This review is limited by the small number of articles, low-sample sizes and the diversity of devices and their associated training protocols, and outcome measures.

CONCLUSIONS

Preliminary evidence suggests robot-assisted interventions are safe, feasible and can reduce active assistance provided by therapists. Implications for rehabilitation Robot-assisted upper extremity training for individuals with cervical spinal cord injury is safe, feasible and can reduce hands-on assistance provided by therapists. Future research in robotics rehabilitation with individuals with spinal cord injury is needed to determine the optimal device and training protocol as well as effectiveness.

Closed-loop afferent electrical stimulation for recovery of hand function in individuals with motor incomplete spinal injury: early clinical results

Afferent electrical stimulation is known to augment the effect of rehabilitative therapy through use-dependent cortical plasticity. Experiments pairing transcranial magnetic stimulation (TMS) with peripheral nerve stimulation (PNS) have shown a timing-dependent effect on motor evoked potential (MEP) amplitude suggesting that PNS applied in closed-loop (CL) mode could augment this effect through positive reinforcement. We present early results from a clinical trial in which an EEG brain-machine interface (BMI) was used to apply PNS to two subjects in response to motor intent detected from sensorimotor cortex in a cue-driven hand grip task. Both subjects had stable incomplete cervical spinal cord injury (SCI) with impaired upper limb function commensurate with the injury level. Twelve sessions of CL-PNS applied over a 4-6 week period yielded results suggesting improved hand grip strength and increased task-related modulation of the EEG in one hand of both subjects, and increased TMS-measured motor map area in one. These observations suggest that rehabilitation using such interactive therapies could benefit affected individuals.

Gait training with Hybrid Assistive Limb enhances the gait functions in subacute stroke patients: A pilot study

BACKGROUND

The robotic Hybrid Assistive Limb (HAL) provides motion according to the wearer's voluntary activity. HAL training effects on walking speed and capacity have not been clarified in subacute stroke.

OBJECTIVES

To determine improvement in walking ability by HAL and the most effective improvement measure for use in future large-scale trials.

METHODS

Sixteen first-ever hemiplegic stroke patients completed at least 20 sessions over 5 weeks. Per session, the experimental group received no more than 20 min of gait training with HAL (HT) and 40 min of conventional physiotherapy, whereas the control group received at least 60 min of conventional physiotherapy. Primary outcome was maximum walking speed (MWS).

RESULTS

The change in MWS from baseline at week 5 was 11.6±10.6 m/min (HAL group) and 2.2±4.1 m/min (control group) (adjusted mean difference = 9.24 m/min, 95% confidence interval 0.48-18.01, P = 0.040). In HAL subjects there were significant increases in Self-selected walking speed (SWS; a secondary outcome) and in step length (a secondary outcome) at MWS and SWS compared with controls.

CONCLUSIONS

HT improved walking speed in hemiplegic sub-acute stroke patients. In future, randomized controlled trials are needed to confirm the utility of HT.

The development of an outcome measures toolkit for spinal cord injury rehabilitation

BACKGROUND

Spinal cord injury (SCI) is a complex medical condition that can be difficult to monitor.

PURPOSE

This study aimed to establish a common set of validated outcome measures specifically for SCI clinical practice.

METHOD

In a three-round online Delphi process, experts in SCI care across Canada suggested and ranked outcome measures for clinical practice. The facilitators provided feedback between rounds and determined if consensus (at least 75% agreement) was reached on a single outcome measure per clinical area.

FINDINGS

One hundred and forty-eight outcome measures were initially considered for inclusion. After three rounds, consensus was reached for 23 out of 30 clinical areas. In the remaining seven, more than one outcome measure was recommended. The final toolkit comprises 33 outcome measures with sufficient measurement properties for use with a SCI population.

IMPLICATIONS

An outcome measures toolkit validated specifically for SCI should lead to improved identification of best practice and enable clinicians to monitor client progress effectively.

Non-invasive brain stimulation and robot-assisted gait training after incomplete spinal cord injury: A randomized pilot study

BACKGROUND

Locomotor training with a robot-assisted gait orthosis (LT-RGO) and transcranial direct current stimulation (tDCS) are interventions that can significantly enhance motor performance after spinal cord injury (SCI). No studies have investigated whether combining these interventions enhances lower extremity motor function following SCI.

OBJECTIVE

Determine whether active tDCS paired with LT-RGO improves lower extremity motor function more than a sham condition, in subjects with motor incomplete SCI.

METHODS

Fifteen adults with SCI received 36 sessions of either active (n = 9) or sham (n = 6) tDCS (20 minutes) preceding LT-RGO (1 hour). Outcome measures included manual muscle testing (MMT; primary outcome measure); 6-Minute Walk Test (6MinWT); 10-Meter Walk Test (10MWT); Timed Up and Go Test (TUG); Berg Balance Scale (BBS); and Spinal Cord Independence Measure-III (SCIM-III).

RESULTS

MMT showed significant improvements after active tDCS, with the most pronounced improvement in the right lower extremity. 10MWT, 6MinWT, and BBS showed improvement for both groups. TUG and SCIM-III showed improvement only for the sham tDCS group.

CONCLUSION

Pairing tDCS with LT-RGO can improve lower extremity motor function more than LT-RGO alone. Future research with a larger sample size is recommended to determine longer-term effects on motor function and activities of daily living.

Observer blind randomised controlled trial of a tailored home exercise programme versus usual care in people with stable inflammatory immune mediated neuropathy

Background

Inflammatory neuropathies such as Guillain-Barré syndrome, chronic inflammatory demyelinating polyradiculoneuropathy and paraproteinaemic demyelinating neuropathy are a heterogenous group of peripheral nerve disorders that affect around one to two people per 100,000. Whilst treatments such as intravenous immunoglobulin, plasma exchange and corticosteroids have generally positive results, long-term residual symptoms and associated activity limitations are common.

There is currently no standardised care for patients with ongoing activity limitation and participation restriction as a result of inflammatory neuropathy IN but data from observational studies and a randomised controlled trial suggest that exercise either alone or as part of a multidisciplinary rehabilitation programme may be beneficial in improving activity limitation. Tailoring the intervention for participants following physiotherapy assessment and incorporating patient preference for type and location of exercise may be important.

Methods/Design

The current study is a pragmatic, prospective, parallel observer-blind, randomised controlled trial to evaluate the efficacy and cost-effectiveness of a twelve week tailored home exercise programme versus advice and usual care. Seventy adults with stable immune mediated inflammatory neuropathy IN will be recruited to the study from two main sources: patients attending selected specialist peripheral nerve clinics in the South East and West Midlands of England and people with who access the GAIN charity website or newsletter. Participants will be randomised to receive either advice about exercise and usual care or a 12 week tailored home exercise programme.

The primary outcome of activity limitation and secondary outcomes of fatigue, quality of life, self-efficacy, illness beliefs, mood and physical activity will be assessed via self-report questionnaire at baseline, 12 weeks and 12 months post intervention. Cost effectiveness and cost utility will be assessed via interview at baseline and 12 months post intervention.

Intention to treat analysis will be our primary model for efficacy analysis. Semi-structured interviews will be conducted with a selected sample of participants in order to explore the acceptability of the intervention and factors affecting adherence to the exercise programme.

Discussion

This is the first randomised controlled trial to compare the efficacy and cost-effectiveness of tailored home exercise with advice about exercise and usual care for adults with inflammatory neuropathy.

Trial registration

Current Controlled Trials ISRCTN13311697

Neuromechanical principles underlying movement modularity and their implications for rehabilitation

Neuromechanical principles define the properties and problems that shape neural solutions for movement. Although the theoretical and experimental evidence is debated, we present arguments for consistent structures in motor patterns, i.e., motor modules, that are neuromechanical solutions for movement particular to an individual and shaped by evolutionary, developmental, and learning processes. As a consequence, motor modules may be useful in assessing sensorimotor deficits specific to an individual and define targets for the rational development of novel rehabilitation therapies that enhance neural plasticity and sculpt motor recovery. We propose that motor module organization is disrupted and may be improved by therapy in spinal cord injury, stroke, and Parkinson's disease. Recent studies provide insights into the yet-unknown underlying neural mechanisms of motor modules, motor impairment, and motor learning and may lead to better understanding of the causal nature of modularity and its underlying neural substrates.

Neurorehabilitation: motor recovery after stroke as an example

The field of neurorehabilitation aims to translate neuroscience research toward the goal of maximizing functional recovery after neurological injury. A growing body of research indicates that the fundamental principles of neurological rehabilitation are applicable to a broad range of congenital, degenerative, and acquired neurological disorders. In this perspective, we will focus on motor recovery after acquired brain injuries such as stroke. Over the past few decades, a large body of basic and clinical research has created an experimental and theoretical foundation for approaches to neurorehabilitation. Recent randomized clinical trials all emphasize the requirement for intense progressive rehabilitation programs to optimally enhance recovery. Moreover, advances in multimodal assessment of patients with neuroimaging and neurophysiological tools suggest the possibility of individualized treatment plans based on recovery potential. There are also promising indications for medical as well as noninvasive brain stimulation paradigms to facilitate recovery. Ongoing or planned clinical studies should provide more definitive evidence. We also highlight unmet needs and potential areas of research. Continued research built upon a robust experimental and theoretical foundation should help to develop novel treatments to improve recovery after neurological injury.

Clinical application of the Hybrid Assistive Limb (HAL) for gait training-a systematic review

OBJECTIVE

The aim of this study was to review the literature on clinical applications of the Hybrid Assistive Limb system for gait training.

METHODS

A systematic literature search was conducted using Web of Science, PubMed, CINAHL and clinicaltrials.gov and additional search was made using reference lists in identified reports. Abstracts were screened, relevant articles were reviewed and subject to quality assessment.

RESULTS

Out of 37 studies, 7 studies fulfilled inclusion criteria. Six studies were single group studies and 1 was an explorative randomized controlled trial. In total, these studies involved 140 participants of whom 118 completed the interventions and 107 used HAL for gait training. Five studies concerned gait training after stroke, 1 after spinal cord injury (SCI) and 1 study after stroke, SCI or other diseases affecting walking ability. Minor and transient side effects occurred but no serious adverse events were reported in the studies. Beneficial effects on gait function variables and independence in walking were observed.

CONCLUSIONS

The accumulated findings demonstrate that the HAL system is feasible when used for gait training of patients with lower extremity paresis in a professional setting. Beneficial effects on gait function and independence in walking were observed but data do not allow conclusions. Further controlled studies are recommended.

Motor learning during poststroke gait rehabilitation: a case study

INTRODUCTION

To develop more effective gait rehabilitation strategies, it is important to understand the time course of motor learning that underlies improvements achieved with gait training. The purpose of this case study was to evaluate motor learning through the measurement of within-session and across-session changes in gait biomechanics during the first and sixth weeks of a 6-week clinical gait training program.

CASE DESCRIPTION

A 47-year-old man with poststroke left hemiparesis participated in the study (15.5 months poststroke, lower extremity Fugl-Meyer score of 12).

INTERVENTION

The subject participated in 6 weeks of training with 3 sessions per week, comprising fast treadmill walking and functional electrical stimulation to plantar and dorsiflexors. In one training session during the first and sixth weeks, paretic propulsion and swing phase knee flexion were measured during a pretest (before the training session), posttest (after the training session), and retention test (48 hours after training).

OUTCOMES

After 6 week of training, the subject's gait speed increased from 0.38 to 0.57 m/s; there was a 55.4% improvement in paretic propulsion and 25% increase in swing phase knee flexion. Examination of change scores revealed greater within-session gains and greater retention during the first versus sixth weeks of gait training for both paretic propulsion and knee flexion.

DISCUSSION

We demonstrate the feasibility and advantage of using within- and across-session changes for evaluating motor learning during clinical gait rehabilitation. An understanding of the time course of motor learning that underlies gait training can guide the development of novel strategies and dosing regimens to increase the efficacy of each session of gait rehabilitation.

VIDEO ABSTRACT AVAILABLE

(See Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A72, for more insights from the authors.).

Are Established Methods of Physiotherapeutic Management for Long-term Neurological Conditions Applicable to 'Orphan' Conditions such as Syringomyelia?

BACKGROUND AND PURPOSE

Syringomyelia is a rare or 'orphan' condition with the potential to cause significant disability and detrimental effects to quality of life. Syringomyelia shares similar symptoms to those common in other long-term neurological conditions, including spinal cord injury and multiple sclerosis. In these more prevalent conditions, physiotherapy is utilized widely and is effective in optimizing physical, psychological and social parameters. Therefore, we theorized that physiotherapy might be transferable to, and beneficial to syringomyelia patients. As a paucity of literature exists in this area, we aimed to evaluate the existing uptake and perceived efficacy of physiotherapy.

METHODS

An exploratory, mixed methodology was selected to derive sufficient qualitative data for analysis. Specifically designed questionnaires and semi-structured interviews yielded data on uptake and perceived physiotherapy efficacy. One hundred patients from a National Health Service tertiary syringomyelia service were invited to participate.

RESULTS

The questionnaire and interviews were completed by 49 and 20 patients, respectively. Of the small number of patients receiving physiotherapy, the majority reported beneficial effects on pain modulation and quality of life. Stretching and hydrotherapy were deemed effective for relief of pain and stiffness. Additionally, physiotherapy was reported to provide similar benefits to surgical intervention.

DISCUSSION

Syringomyelia patients report physiotherapy to provide benefits for symptom management and quality of life. Such findings suggest that established rehabilitation techniques in more common conditions may be transferable to those less prevalent. Uptake of physiotherapy was limited, seemingly because of inadequate information, knowledge and resources. To address these deficiencies, further studies should be planned investigating the effectiveness of physiotherapy modalities, such as hydrotherapy, in parallel or in conjunction with surgery and/or pharmacology. Additionally, syringomyelia could be represented alongside similar pathologies in research trials to initiate further research questions and drivers for funding.

Virtual reality training for upper extremity in subacute stroke (VIRTUES): study protocol for a randomized controlled multicenter trial

Background

Novel virtual reality rehabilitation systems provide the potential to increase intensity and offer challenging and motivating tasks. The efficacy of virtual reality systems to improve arm motor function early after stroke has not been demonstrated yet in sufficiently powered studies. The objective of the study is to investigate whether VR training as an adjunct to conventional therapy is more effective in improving arm motor function in the subacute phase after stroke than dose-matched conventional training, to assess patient and therapist satisfaction when working with novel virtual reality training and to calculate cost-effectiveness in terms of resources required to regain some degree of dexterity.

Methods/Design

Randomized controlled observer-blind trial.

One hundred and twenty patients up to 12 weeks after stroke will be randomized to either a group receiving VR training or dose-matched and therapist attention-matched conventional arm training in addition to standard rehabilitation. During a period of four weeks the patients will be offered additional 4–5 training sessions a week of 45–60 minutes duration by a physiotherapist or an occupational therapist.

Study outcomes: Arm motor function, dexterity and independence in daily life activities will be evaluated at baseline, post treatment and three months follow-up assessments with the Action Research Arm Test, Box and Blocks Test and the Functional Independence Measure, respectively. Patient and therapist satisfaction with the implementation of a VR rehabilitation system will also be assessed with questionnaires and interviews.

Discussion

Virtual reality systems are promising tools for rehabilitation of arm motor function after stroke. Their introduction in combination with traditional physical and occupational therapy may enhance recovery after stroke, and at the same time demand little personnel resources to increase training intensity. The VIRTUES trial will provide further evidence of VR-based treatment strategies to clinicians, patients and health economists.

Trial registration

ClinicalTrials.gov NCT02079103

EMG activity of finger flexor muscles and grip force following low-dose transcutaneous electrical nerve stimulation in healthy adult subjects

Somatosensory stimulation modulates cortical and corticospinal excitability and consequently affects motor output. Therefore, low-amplitude transcutaneous electrical nerve stimulation (TENS) has the potential to elicit favorable motor responses. The purpose of the two presented pilot studies was to shed light on TENS parameters that are relevant for the enhancement of two desirable motor outcomes, namely, electromyographic (EMG) activity and contraction strength of the finger flexors and wrist muscles. In 5 and 10 healthy young adults (in Study I and Study II, respectively) TENS was delivered to the volar aspect of the forearm. We manipulated TENS frequency (150 Hz vs. 5 Hz), length of application (10, 20, and 60 min), and side of application (unilateral, right forearm vs. bilateral forearms). EMG amplitude and grip force were measured before (Pre), immediately after (Post), and following 15 min of no stimulation (Study I only). The results indicated that low-frequency bursts of TENS applied to the skin overlying the finger flexor muscles enhance the EMG activity of the finger flexors and grip force. The increase in EMG activity of the flexor muscles was observed after 20 min of stimulation, while grip force was increased only after 1 h. The effects of uni- and bilateral TENS were comparable. These observations allude to a modulatory effect of TENS on the tested motor responses; however, unequivocal conclusions of the findings are hampered by individual differences that affect motor outcomes, such as in level of attention.

Gait training early after stroke with a new exoskeleton--the hybrid assistive limb: a study of safety and feasibility

Background

Intensive task specific training early after stroke may enhance beneficial neuroplasticity and functional recovery. Impaired gait after hemiparetic stroke remains a challenge that may be approached early after stroke by use of novel technology. The aim of the study was to investigate the safety and feasibility of the exoskeleton Hybrid Assistive Limb (HAL) for intensive gait training as part of a regular inpatient rehabilitation program for hemiparetic patients with severely impaired gait early after stroke.

Methods

Eligible were patients until 7 weeks after hemiparetic stroke. Training with HAL was performed 5 days per week by the autonomous and/or the voluntary control mode offered by the system. The study protocol covered safety and feasibility issues and aspects on motor function, gait performance according to the 10 Meter Walking Test (10MWT) and Functional Ambulation Categories (FAC), and activity performance.

Results

Eight patients completed the study. Median time from stroke to inclusion was 35 days (range 6 to 46). Training started by use of the autonomous HAL mode in all and later switched to the voluntary mode in all but one and required one or two physiotherapists. Number of training sessions ranged from 6 to 31 (median 17) and walking time per session was around 25 minutes. The training was well tolerated and no serious adverse events occurred. All patients improved their walking ability during the training period, as reflected by the 10MWT (from 111.5 to 40 seconds in median) and the FAC (from 0 to 1.5 score in median).

Conclusions

The HAL system enables intensive training of gait in hemiparetic patients with severely impaired gait function early after stroke. The system is safe when used as part of an inpatient rehabilitation program for these patients by experienced physiotherapists.

Short-term maximal-intensity resistance training increases volitional function and strength in chronic incomplete spinal cord injury: a pilot study

BACKGROUND AND PURPOSE

Recent research shows that individuals with an incomplete spinal cord injury (SCI) have a reserve of force-generating capability that is observable during repeated intermittent maximal volitional effort contractions. Previous studies suggest that increased neural drive contributes to the enhanced short-term force-generating capabilities. Whether this reserve can be harnessed with repeated training is unclear. The purpose of this pilot study was to investigate the effects of 4 weeks of maximal-intensity resistance training, compared with conventional progressive resistance training, on lower extremity function and strength in chronic incomplete SCI.

METHODS

Using a randomized crossover design, 5 individuals with chronic (> 1 year postinjury) SCI American Spinal Injury Association Impairment Scale classification C or D were tested before and after 4 weeks of both maximal-intensity training and progressive resistance training paradigms. Outcomes measures included the 6-Minute Walk Test, the Berg Balance Scale, and peak isometric torque for strength of lower extremity muscles.

RESULTS

Maximal-intensity resistance training was associated with an average increase of 12.19 ± 8.29 m on the 6-Minute Walk Test, 4 ± 1.9 points on the Berg Balance Scale, 4 ± 4.5 points on the lower extremity motor score), while no changes on the above scores were seen with conventional training. Furthermore, significant increases in peak volitional isometric torques (mean increase = 20 ± 8 Nm) were observed following maximal-intensity resistance training when compared with conventional training (mean increase = 0.12 ± 3 Nm, P = 0.03).

DISCUSSION AND CONCLUSIONS

Maximal-intensity training paradigm may facilitate rapid gains in volitional function and strength in persons with chronic motor-incomplete SCI, using a simple short-term training paradigm.

Activity-dependent neural plasticity from bench to bedside

Much progress has been made in understanding how behavioral experience and neural activity can modify the structure and function of neural circuits during development and in the adult brain. Studies of physiological and molecular mechanisms underlying activity-dependent plasticity in animal models have suggested potential therapeutic approaches for a wide range of brain disorders in humans. Physiological and electrical stimulations as well as plasticity-modifying molecular agents may facilitate functional recovery by selectively enhancing existing neural circuits or promoting the formation of new functional circuits. Here, we review the advances in basic studies of neural plasticity mechanisms in developing and adult nervous systems and current clinical treatments that harness neural plasticity, and we offer perspectives on future development of plasticity-based therapy.

Interventions to Improve Walking in Older Adults

Interventions to improve walking in older adults have historically been multifactorial (i.e. strengthening, endurance and flexibility programs) focusing on improving the underlying impairments. These impairment-based programs have resulted in only modest improvements in walking. In older adults, walking is slow, less stable, inefficient, and the timing and coordination of stepping with postures and phases of gait is poor. We argue the timing and coordination problems are evidence of the loss of motor skill in walking. Taking a lesson from the sports world and from neurorehabilitation, task-oriented motor learning exercise is an essential component of training to improve motor skill and may be a beneficial approach to improving walking in older adults. In this article we: 1) briefly review the current literature regarding impairment-based interventions for improving mobility, 2) discuss why the results have been only modest, and 3) suggest an alternative approach to intervention (i.e. task oriented motor learning).

Multimodal exercises simultaneously stimulating cortical and brainstem pathways after unilateral corticospinal lesion

In the context of injury to the corticospinal tract (CST), brainstem-origin circuits may provide an alternative system of descending motor influence. However, subcortical circuits are largely under subconscious control. To improve volitional control over spared fibers after CST injury, we hypothesized that a combination of physical exercises simultaneously stimulating cortical and brainstem pathways above the injury would strengthen corticobulbar connections through Hebbian-like mechanisms. We sought to test this hypothesis in mice with unilateral CST lesions. Ten days after pyramidotomy, mice were randomized to four training groups: (1) postural exercises designed to stimulate brainstem pathways (BS); (2) distal limb-grip exercises preferentially stimulating CST pathways (CST); (3) simultaneous multimodal exercises (BS+CST); or (4) no training (NT). Behavioral and anatomical outcomes were assessed after 20 training sessions over 4 weeks. Mice in the BS+CST training group showed a trend toward greater improvements in skilled limb performance than mice in the other groups. There were no consistent differences between training groups in gait kinematics. Anatomically, multimodal BS+CST training neither increased corticobulbar fiber density of the lesioned CST rostral to the lesion nor collateral sprouting of the unlesioned CST caudal to the lesion. Further studies should incorporate electrophysiological assessment to gauge changes in synaptic strength of direct and indirect pathways between the cortex and spinal cord in response to multimodal exercises.

Noninvasive strategies to promote functional recovery after stroke

Stroke is a common and disabling global health-care problem, which is the third most common cause of death and one of the main causes of acquired adult disability in many countries. Rehabilitation interventions are a major component of patient care. In the last few years, brain stimulation, mirror therapy, action observation, or mental practice with motor imagery has emerged as interesting options as add-on interventions to standard physical therapies. The neural bases for poststroke recovery rely on the concept of plasticity, namely, the ability of central nervous system cells to modify their structure and function in response to external stimuli. In this review, we will discuss recent noninvasive strategies employed to enhance functional recovery in stroke patients and we will provide an overview of neural plastic events associated with rehabilitation in preclinical models of stroke.

Bilateral movement training promotes axonal remodeling of the corticospinal tract and recovery of motor function following traumatic brain injury in mice

Traumatic brain injury (TBI) results in severe motor function impairment, and subsequent recovery is often incomplete. Rehabilitative training is considered to promote restoration of the injured neural network, thus facilitating functional recovery. However, no studies have assessed the effect of such trainings in the context of neural rewiring. Here, we investigated the effects of two types of rehabilitative training on corticospinal tract (CST) plasticity and motor recovery in mice. We injured the unilateral motor cortex with contusion, which induced hemiparesis on the contralesional side. After the injury, mice performed either a single pellet-reaching task (simple repetitive training) or a rotarod task (bilateral movement training). Multiple behavioral tests were then used to assess forelimb motor function recovery: staircase, ladder walk, capellini handling, single pellet, and rotarod tests. The TBI+rotarod group performed most forelimb motor tasks (staircase, ladder walk, and capellini handling tests) better than the TBI-only group did. In contrast, the TBI+reaching group did not perform better except in the single pellet test. After the injury, the contralateral CST, labeled by biotinylated dextran amine, formed sprouting fibers into the denervated side of the cervical spinal cord. The number of these fibers was significantly higher in the TBI+rotarod group, whereas it did not increase in the TBI+reaching group. These results indicate that bilateral movement training effectively promotes axonal rewiring and motor function recovery, whereas the effect of simple repetitive training is limited.

Functional neurological recovery after spinal cord injury is impaired in patients with infections

Infections are a common threat to patients after spinal cord injury. Furthermore, infections might propagate neuronal death, and consequently contribute to the restriction of neurological recovery. We investigated the association of infections (i.e. pneumonia and/or postoperative wound infections) with functional neurological outcome after acute severe traumatic spinal cord injury. We screened data sets of 24 762 patients enrolled in a prospective cohort study (National Spinal Cord Injury Database, Birmingham, AL, USA). Patients were assessed according to the ASIA classification. ASIA impairment scale-classified A and B patients recruited within 24 h post-trauma (n = 1436) were selected as being a major recruitment population for interventional trials. Patients with documented pneumonia and/or postoperative wound infections (n = 581) were compared with control subjects (non-documented infections, n = 855). The functional neurological outcome parameters (i) upward ASIA impairment scale conversions; (ii) gain of ASIA motor scores; and (iii) gain of motor and sensory levels were consecutively analysed over time up to 1 year after spinal cord injury. The group with pneumonia and/or postoperative wound infections revealed less ASIA impairment scale upward conversions after 1 year than the control group (ASIA impairment scale A: 17.2 versus 23.9%, P = 0.03; ASIA impairment scale B: 57.1 versus 74.7%, P = 0.009). ASIA motor score gain [median (interquartile range)] was lower in patients with infections [ASIA impairment scale A: 8 (4-12) versus 10 (5-17), P = 0.01; ASIA impairment scale B: 19.5 (8-53.5) versus 42 (20.5-64), P = 0.03)]. Analysis of acquired motor/sensory levels supported these findings. In ASIA impairment scale A patients, the gain in motor levels (21.7 versus 33.3%, P = 0.04) and sensory levels (24.4 versus 38 of 102, 37.3%, P = 0.03) was significantly lower in the group with pneumonia and/or postoperative wound infections than in the control group. Multiple regression analysis identified pneumonia and/or postoperative wound infections as independent risk factors for impaired ASIA impairment scale upward conversion (odds ratio: 1.89, 95% confidence interval: 1.36-2.63, P < 0.0005) or lower gain in ASIA motor score (regression coefficient: -8.21, 95% confidence interval: -12.29 to -4.14, P < 0.0005). Infections associated with spinal cord injury, such as pneumonia and/or postoperative wound infections, qualify as independent risk factors for poor neurological outcome after motor complete spinal cord injury. Infections constitute a clinically relevant target for protecting the limited endogenous functional regeneration capacity. Upcoming interventional trials might gain in efficacy with improved patient stratification and might benefit from complementary protection of the intrinsic recovery potential after spinal cord injury.

Introduction: the evolving field of neurorehabilitation

Over the past 15 years, our understanding of how the nervous system responds to brain injury, spinal cord injury, and stroke has expanded exponentially. Research demonstrates that the CNS, once thought to be unable to regenerate, maintains a degree of plasticity that responds to activity and pharmacologic therapy, producing both neurophysiologic changes and clinical recovery. Removing barriers to optimize axonal regrowth appears to further enhance this plasticity. Functional imaging, magnetic stimulation, and quantitative electroencephalography allow investigators to localize and monitor changes in brain activity during both spontaneous recovery and treatment paradigms. Neurorehabilitation research is difficult and funding is insufficient. Newer research approaches and better collaboration between researchers and clinicians are warranted. Clinical adoption is slow because of cost and time pressures. Demonstration that treatments promoting CNS plasticity result in better functional outcomes and reduced overall costs is needed.

Treadmill training in multiple sclerosis: can body weight support or robot assistance provide added value? A systematic review

Purpose. This systematic review critically analyzes the literature on the effectiveness of treadmill training (TT), body-weight-supported TT (BWSTT), and robot-assisted TT (RATT) in persons with multiple sclerosis (MS), with focus on gait-related outcome measurements. Method. Electronic databases (Pubmed, Pedro, Web of Science, and Cochrane Library) and reference lists of articles and narrative reviews were searched. Pre-, quasi- and true-experimental studies were included if adult persons with MS were involved in TT, BWSTT, or RATT intervention studies published before 2012. Descriptive analysis was performed and two researchers scored the methodological quality of the studies. Results. 5 true- and 3 preexperimental studies (mean quality score: 66%) have been included. In total 161 persons with MS were involved (TT, BWSTT, or RATT, 6–42 sessions; 2–5x/week; 3–21 weeks). Significant improvements in walking speed and endurance were reported. Furthermore, improvements of step length, double-support time, and Expanded Disability Status Scale were found. Conclusions. There is a limited number of published papers related to TT in persons with MS, concluding that TT, BWSTT, and RATT improve the walking speed and endurance. However, it is not clear what type of TT is most effective. RCTs with larger but more homogeneous populations are needed.

Valid and reliable instruments for arm-hand assessment at ICF activity level in persons with hemiplegia: a systematic review

BACKGROUND

Loss of arm-hand performance due to a hemiparesis as a result of stroke or cerebral palsy (CP), leads to large problems in daily life of these patients. Assessment of arm-hand performance is important in both clinical practice and research. To gain more insight in e.g. effectiveness of common therapies for different patient populations with similar clinical characteristics, consensus regarding the choice and use of outcome measures is paramount. To guide this choice, an overview of available instruments is necessary. The aim of this systematic review is to identify, evaluate and categorize instruments, reported to be valid and reliable, assessing arm-hand performance at the ICF activity level in patients with stroke or cerebral palsy.

METHODS

A systematic literature search was performed to identify articles containing instruments assessing arm-hand skilled performance in patients with stroke or cerebral palsy. Instruments were identified and divided into the categories capacity, perceived performance and actual performance. A second search was performed to obtain information on their content and psychometrics.

RESULTS

Regarding capacity, perceived performance and actual performance, 18, 9 and 3 instruments were included respectively. Only 3 of all included instruments were used and tested in both patient populations. The content of the instruments differed widely regarding the ICF levels measured, assessment of the amount of use versus the quality of use, the inclusion of unimanual and/or bimanual tasks and the inclusion of basic and/or extended tasks.

CONCLUSIONS

Although many instruments assess capacity and perceived performance, a dearth exists of instruments assessing actual performance. In addition, instruments appropriate for more than one patient population are sparse. For actual performance, new instruments have to be developed, with specific focus on the usability in different patient populations and the assessment of quality of use as well as amount of use. Also, consensus about the choice and use of instruments within and across populations is needed.

Combined Transcranial Direct Current Stimulation and Robot-Assisted Arm Training in Subacute Stroke Patients

Background. No rehabilitation intervention has effectively improved functional use of the arm and hand in patients with severe upper limb paresis after stroke. Pilot studies suggest the potential for transcranial direct current stimulation and bilateral robotic training to enhance gains. Objective. In a double-blind, randomized trial the combination of these interventions was tested. Methods. This study randomized 96 patients with an ischemic supratentorial lesion of 3 to 8 weeks’ duration with severe impairment of motor control with a Fugl-Meyer score (FMS) for the upper limb <18 into 3 groups. For 6 weeks, group A received anodal stimulation of the lesioned hemisphere, group B received cathodal stimulation of the nonlesioned side for 20 minutes at 2.0 mA, and group C received sham stimulation. The electrodes were placed over the hand area and above the contralateral orbit. Contemporaneously, the subjects practiced 400 repetitions each of 2 different bilateral movements on a robotic assistive device. Results. The groups were matched at onset. The FMS improved in all patients at 6 weeks ( P < .001). No between-group differences were found; initial versus finish FMS scores were 7.8 ± 3.8 versus 19.1 ± 14.4 in group A, 7.9 ± 3.4 versus 18.8 ± 10.5 in group B, and 8.2 ± 4.4 versus 19.2 ± 15.0 in group C. No significant changes between groups were present at 3 months. Conclusions. Neither anodal nor cathodal transcranial direct current stimulation enhanced the effect of bilateral arm training in this exploratory trial of patients with cortical involvement and severe weakness. Unilateral hand training and upregulation of the nonlesioned hemisphere might also be tried in this population.

Horizontal ladder task-specific re-training in adult rats with contusive thoracic spinal cord injury

PURPOSE

Using the horizontal ladder task, we examined some issues that need to be resolved before task-specific rehabilitative training can be employed clinically for the frequent contusive spinal cord injury (SCI). We hypothesized that improving recovery in task performance after contusive thoracic SCI requires frequent re-training and initiating the re-training early during spontaneous recovery.

METHODS

Contusive SCI was produced at the adult female Sprague Dawley rat T10 vertebra. Task re-training was initiated one week later when occasional weight-supported plantar steps were taken overground (n = 8). It consisted of 2 repetitions each day, 5 days each week, for 3 weeks. Task performance and overground locomotion were assessed weekly. Neurotransmission through the SCI ventrolateral funiculus was examined. SCI morphometry was determined.

RESULTS

Re-training did not improve task performance recovery compared to untrained Controls (n = 7). Untrained overground locomotion and neurotransmission through the SCI did not change. Lesion area at the injury epicenter as a percentage of the total spinal cord area as well as total tissue, lesion, and spared tissue, white matter, or gray matter volumes did not differ.

CONCLUSIONS

For the horizontal ladder task after contusive thoracic SCI, earlier re-training sessions with more repetitions and critical neural circuitry may be necessary to engender a rehabilitation effect.

Rehabilitation outcomes: values, methodologies and applications

BACKGROUND

Just what defines a 'good' outcome in rehabilitation has been a much-debated issue. Indeed, this question remains a major focus in research, clinical practice and policy (with funding in many countries now being linked to outcomes achieved rather than outputs or services provided). Despite this rather constant attention, complexity, contention and confusion remain.

PURPOSE

This special issue presents 10 papers that take a fresh look at some of the long-standing problems concerning rehabilitation outcomes and, proposes novel ways to reconsider things and move forward.

RESULTS

In this article, we provide a brief commentary on key issues raised by authors all of which focus on one or more of the following three key themes: the place of values in selecting and targeting outcomes; novel methodologies that may usefully inform measurement of outcome and finally; application of the thinking about outcomes in specific examples.

CONCLUSION

The papers in this special issue address a number of key issues concerning the evaluation of outcomes in rehabilitation. In so doing, some of the prevalent assumptions underpinning common approaches are questioned and novel ways forward are proposed.