Stance Phase Gait Training Post Stroke Using Simultaneous Transcranial Direct Current Stimulation and Motor Learning-Based Virtual Reality-Assisted Therapy: Protocol Development and Initial Testing.

Gait deficits are often persistent after stroke, and current rehabilitation methods do not restore normal gait for everyone. Targeted methods of focused gait therapy that meet the individual needs of each stroke survivor are needed. Our objective was to develop and test a combination protocol of simultaneous brain stimulation and focused stance phase training for people with chronic stroke (>6 months). We combined Transcranial Direct Current Stimulation (tDCS) with targeted stance phase therapy using Virtual Reality (VR)-assisted treadmill training and overground practice. The training was guided by motor learning principles. Five users (>6 months post-stroke with stance phase gait deficits) completed 10 treatment sessions. Each session began with 30 min of VR-assisted treadmill training designed to apply motor learning (ML)-based stance phase targeted practice. During the first 15 min of the treadmill training, bihemispheric tDCS was simultaneously delivered. Immediately after, users completed 30 min of overground (ML)-based gait training. The outcomes included the feasibility of protocol administration, gait speed, Timed Up and Go (TUG), Functional Gait Assessment (FGA), paretic limb stance phase control capability, and the Fugl−Meyer for lower extremity coordination (FMLE). The changes in the outcome measures (except the assessments of stance phase control capability) were calculated as the difference from baseline. Statistically and clinically significant improvements were observed after 10 treatment sessions in gait speed (0.25 ± 0.11 m/s) and FGA (4.55 ± 3.08 points). Statistically significant improvements were observed in TUG (2.36 ± 3.81 s) and FMLE (4.08 ± 1.82 points). A 10-session intervention combining tDCS and ML-based task-specific gait rehabilitation was feasible and produced clinically meaningful improvements in lower limb function in people with chronic gait deficits after stroke. Because only five users tested the new protocol, the results cannot be generalized to the whole population. As a contribution to the field, we developed and tested a protocol combining brain stimulation and ML-based stance phase training for individuals with chronic stance phase deficits after stroke. The protocol was feasible to administer; statistically and/or clinically significant improvements in gait function across an array of gait performance measures were observed with this relatively short treatment protocol.

Myoelectric Arm Orthosis in Motor Learning-Based Therapy for Chronic Deficits After Stroke and Traumatic Brain Injury.

BACKGROUND: Technologies that enhance motor learning-based therapy and are clinically deployable may improve outcome for those with neurological deficits. The MyoPro™ is a customized myoelectric upper extremity orthosis that utilizes volitionally generated weak electromyographic signals from paretic muscles to assist movement of an impaired arm. Our purpose was to evaluate MyoPro as a tool for motor learning-based therapy for individuals with chronic upper limb weakness. METHODS: This was a pilot study of thirteen individuals with chronic moderate/severe arm weakness due to either stroke (n = 7) or TBI (n = 6) who participated in a single group interventional study consisting of 2 phases. The in-clinic phase included 18 sessions (2x per week, 27hrs of face-to-face therapy) plus a home exercise program. The home phase included practice of the home exercise program. The study did not include a control group. Outcomes were collected at baseline and at weeks 3, 5, 7, 9, 12, 15, and 18. Statistics included mixed model regression analysis. RESULTS: Statistically significant and clinically meaningful improvements were observed on Fugl-Meyer (+7.5 points). Gains were seen at week 3, increased further through the in-clinic phase and were maintained during the home phase. Statistically significant changes in Modified Ashworth Scale, Range of Motion, and Chedoke Arm and Hand Activity Inventory were seen early during the in-clinic phase. Orthotic and Prosthetic User's Survey demonstrated satisfaction with the device throughout study participation. Both stroke and TBI participants responded to the intervention. CONCLUSIONS: Use of MyoPro in motor learning-based therapy resulted in clinically significant gains with a relatively short duration of in-person treatment. Further studies are warranted. CLINICAL TRIAL REGISTRATION: www.ClinicalTrials.gov, identifier: NCT03215771.

Does rTMS Targeting Contralesional S1 Enhance Upper Limb Somatosensory Function in Chronic Stroke? A Proof-of-Principle Study.

BACKGROUND: Somatosensory deficits are prevalent after stroke, but effective interventions are limited. Brain stimulation of the contralesional primary somatosensory cortex (S1) is a promising adjunct to peripherally administered rehabilitation therapies. OBJECTIVE: To assess short-term effects of repetitive transcranial magnetic stimulation (rTMS) targeting contralesional (S1) of the upper extremity. METHODS: Using a single-session randomized crossover design, stroke survivors with upper extremity somatosensory loss participated in 3 rTMS treatments targeting contralesional S1: Sham, 5 Hz, and 1 Hz. rTMS was delivered concurrently with peripheral of sensory electrical stimulation and vibration of the affected hand. Outcomes included 2-point discrimination (2PD), proprioception, vibration perception threshold, monofilament threshold (size), and somatosensory evoked potential (SEP). Measures were collected before, immediately after treatment, and 1 hour after treatment. Mixed models were fit to analyze the effects of the 3 interventions. RESULTS: Subjects were 59.8 ± 8.1 years old and 45 ± 39 months poststroke. There was improvement in 2PD after 5-Hz rTMS for the stroke-affected (F(2, 76.163) = 3.5, P = .035) and unaffected arm (F(2, 192.786) = 10.6, P < .0001). Peak-to-peak SEP amplitudes were greater after 5-Hz rTMS for N33-P45 (F(2, 133.027) = 3.518, P = .032) and N45-P60 (F(2, 67.353) = 3.212, P = .047). Latencies shortened after 5-Hz rTMS for N20 (F(2, 69.64) = 3.37, P = .04), N60 (F(2, 47.343) = 4.375, P = .018), and P100 (F(2, 37.608) = 3.537, P = .039) peaks. There were no differences between changes immediately after the intervention and an hour later. CONCLUSIONS: Short-term application of facilitatory high-frequency rTMS (5Hz) to contralesional S1 combined with peripheral somatosensory stimulation may promote somatosensory function. This intervention may serve as a useful adjunct in somatosensory rehabilitation after stroke.

Use of a myoelectric upper limb orthosis for rehabilitation of the upper limb in traumatic brain injury: A case report.

BACKGROUND: Upper limb motor deficits following traumatic brain injury are prevalent and effective therapies are needed. The purpose of this case report was to illustrate response to a novel therapy using a myoelectric orthosis in a person with TBI.Case description: A 42-year-old female, 29.5 years post-traumatic brain injury with diminished motor control/coordination, and learned nonuse of the right arm. She also had cognitive deficits and did not spontaneously use her right arm functionally. INTERVENTION: Study included three phases: baseline data collection/device fabrication (five weeks); in-clinic training (2×/week for nine weeks); and home-use phase (nine weeks). The orthosis was incorporated into motor learning-based therapy.Outcomes: During in-clinic training, active range of motion, tone, muscle power, Fugl-Meyer, box and blocks test, and Chedoke assessment score improved. During the home-use phase, decrease in tone was maintained and all other outcomes declined but were still better upon study completion than baseline. The participant trained with the orthosis 70.12 h, logging over 13,000 repetitions of elbow flexion/extension and hand open/close. DISCUSSION: Despite long-standing traumatic brain injury, meaningful improvements in motor function were observed and were likely the results of high repetition practice of functional movement delivered over a long duration. Further assessment in a larger cohort is warranted.

A model-based study of internuclear ophthalmoparesis and ocular-motor fatigue in multiple sclerosis.

Internuclear ophthalmoparesis (INO) in multiple sclerosis (MS) is due to demyelination of the medial longitudinal fasciculus (MLF). INO is typically modeled as an increased peak-velocity and peak-acceleration ratio of abducting to adducting eye (pulse-size ratio, PSR). PSR can be affected by fatigue during prolonged ocular-motor tasks (ocular-motor fatigue). We propose that an important component of horizontal disconjugacy in INO is due to a delayed delivery of the saccadic pulse to the adducting eye (pulse-time delay, PTD). We expanded a control-system model to account for both abnormal PSR and PTD reflecting faulty axonal transmission in INO and to provide a better understanding of possible changes induced by fatigue. Saccades were measured in 19 MS patients with INO and 10 controls, using a 10-min saccadic "fatigue test" consisting of repetitive back-to-back 20° saccades. In the horizontal saccades model the unitary MLF connection was partitioned into parallel sub-tracts representing progressive degrees of disease effect. INO patients showed baseline abnormal PSR and PTD with some changes during the fatigue test. Manipulations of gain and transmission delay in the model provided simulated saccades that closely resembled those of INO. Ocular-motor fatigue may be a heterogeneous phenomenon that involves inter-saccadic fluctuation of PSR and PTD and adaptation during demanding ocular-motor tasks. INO as a model of abnormal axonal conduction has a potential role in assessing efficacy of reparative therapies in MS.

Feasibility and clinical experience of implementing a myoelectric upper limb orthosis in the rehabilitation of chronic stroke patients: A clinical case series report.

Individuals with stroke are often left with persistent upper limb dysfunction, even after treatment with traditional rehabilitation methods. The purpose of this retrospective study is to demonstrate feasibility of the implementation of an upper limb myoelectric orthosis for the treatment of persistent moderate upper limb impairment following stroke (>6 months). METHODS: Nine patients (>6 months post stroke) participated in treatment at an outpatient Occupational Therapy department utilizing the MyoPro myoelectric orthotic device. Group therapy was provided at a frequency of 1-2 sessions per week (60-90 minutes per session). Patients were instructed to perform training with the device at home on non-therapy days and to continue with use of the device after completion of the group training period. Outcome measures included Fugl-Meyer Upper Limb Assessment (FM) and modified Ashworth Scale (MAS). RESULTS: Patients demonstrated clinically important and statistically significant improvement of 9.0±4.8 points (p = 0.0005) on a measure of motor control impairment (FM) during participation in group training. It was feasible to administer the training in a group setting with the MyoPro, using a 1:4 ratio (therapist to patients). Muscle tone improved for muscles with MAS >1.5 at baseline. DISCUSSION: Myoelectric orthosis use is feasible in a group clinic setting and in home-use structure for chronic stroke survivors. Clinically important motor control gains were observed on FM in 7 of 9 patients who participated in training.

Association of spasticity and motor dysfunction in chronic stroke.

BACKGROUND: The prevalence of increased muscle tone after stroke is frequently reported as 30% to 40%, and the condition is often concurrent with motor control deficits, manifesting as an inability to isolate paretic-limb joint movements. OBJECTIVE: The objectives of this retrospective analysis were to 1) report the prevalence of increased muscle tone in a convenience sample of 128 chronic stroke survivors with moderate/severe motor deficits and 2) quantify the relation between tone and motor impairment in chronic stroke survivors. METHODS: Analyses included descriptive statistics and multiple regression modeling, with the modified Ashworth Scale score (MAS; tone) as a predictor of isolated joint movement control (Fugl-Meyer score [FM]; motor impairment). RESULTS: Increased muscle tone was present in 97% of subjects. Increased muscle tone was associated with impaired motor control (FM; upper extremity, P=0.008; lower extremity, P=0.03) after adjusting for age, time since stroke and sex. We found a significant difference between flexor and extensor strength for finger, elbow, hip and knee joints (P<0.002). Participants were classified in high and low MAS score groups. With high MAS score and for muscles of finger flexion and forearm pronation, we found a trend toward impaired strength of antagonist muscles (finger extensors and forearm supinators, respectively) as compared with low MAS score for these same muscle pairings. CONCLUSIONS: The prevalence of increased tone was higher in this study than in previous reports. Increased muscle tone in chronic stroke survivors with persistent motor dysfunction could be associated with impaired motor control and differential muscle strength of antagonistic muscles.

Greater Cortical Thickness Is Associated With Enhanced Sensory Function After Arm Rehabilitation in Chronic Stroke.

OBJECTIVE: Somatosensory function is critical to normal motor control. After stroke, dysfunction of the sensory systems prevents normal motor function and degrades quality of life. Structural neuroplasticity underpinnings of sensory recovery after stroke are not fully understood. The objective of this study was to identify changes in bilateral cortical thickness (CT) that may drive recovery of sensory acuity. METHODS: Chronic stroke survivors (n = 20) were treated with 12 weeks of rehabilitation. Measures were sensory acuity (monofilament), Fugl-Meyer upper limb and CT change. Permutation-based general linear regression modeling identified cortical regions in which change in CT was associated with change in sensory acuity. RESULTS: For the ipsilesional hemisphere in response to treatment, CT increase was significantly associated with sensory improvement in the area encompassing the occipital pole, lateral occipital cortex (inferior and superior divisions), intracalcarine cortex, cuneal cortex, precuneus cortex, inferior temporal gyrus, occipital fusiform gyrus, supracalcarine cortex, and temporal occipital fusiform cortex. For the contralesional hemisphere, increased CT was associated with improved sensory acuity within the posterior parietal cortex that included supramarginal and angular gyri. Following upper limb therapy, monofilament test score changed from 45.0 ± 13.3 to 42.6 ± 12.9 mm ( P = .063) and Fugl-Meyer score changed from 22.1 ± 7.8 to 32.3 ± 10.1 ( P < .001). CONCLUSIONS: Rehabilitation in the chronic stage after stroke produced structural brain changes that were strongly associated with enhanced sensory acuity. Improved sensory perception was associated with increased CT in bilateral high-order association sensory cortices reflecting the complex nature of sensory function and recovery in response to rehabilitation.