Immediate effects of functional electrical orthoses in gait of hemiparetic patients

Introduction: Functional electrical orthoses may favor ankle dorsiflexion in hemiparetic patients. Objective: The objective of this study was to evaluate the immediate effects of using the functional orthosis in the gait of hemiparetic patients. Methods: The research was performed on 10 participants with diagnosis of hemiparesis. The participants selected for this research were evaluated both with and without the use of the WalkAide® System functional electrical orthosis conducted via the 10-meter walk test and baropodometry. Results: The samples of this study were characterized by male participants averaging in age from 52,7 ± 15,3 years. The participants presented an inferior displacement time (25,64 ± 11,42 s) with the use of the functional electrical orthosis when compared to the displacement time without the orthosis (27,68 ± 12,99 s). With regards to the baropodometric data, there were significant differences in the contact area of the forefoot and the hindfoot with the use of the functional electrical orthosis. Conclusion: Functional electrical orthosis yielded immediate satisfactory results in the gait of hemiparetic patients

Cortical activation during executed, imagined, and observed foot movements.

Evidence suggests that executed, imagined, and observed movements share neural substrates, however, brain activation during the performance of these three tasks has not yet been examined during lower extremity movements. Functional MRI was performed in 10 healthy right-footed participants during imagined, executed, and observed right ankle movements. Task compliance was high, confirmed via behavioral assessment and electromyographic measurements. Each task was also associated with its own profile of regional activation, however, overall, regional activation showed substantial overlap across the three lower extremity motor tasks. The findings suggest the utility of continued efforts to develop motor imagery and observation programs for improving lower extremity function in a range of clinical settings

Changes in Walking Spatiotemporal Parameters After Therapeutic Yoga in People with Chronic Stroke

Walking limitations after stroke can contribute to long-term functional impairments. Walking characteristics such as spatiotemporal step parameters may be associated with these persistent walking limitations. The purpose of this study was to investigate changes in specific spatiotemporal walking parameters such as: walking speed; step length; swing time; step parameter symmetry; and double support time in adults with stroke who were participating in a therapeutic yoga intervention. The therapeutic yoga intervention was offered as a post-rehabilitation wellness activity 2 times per week for 8 weeks and was led by a yoga therapist. Spatiotemporal walking data were collected using the GAITRite Walkway System on a sub sample (n=24) of participants in a randomized controlled trial testing the efficacy of therapeutic yoga for improving balance in adults with chronic stroke. These data demonstrated that therapeutic yoga may have a positive impact on some spatiotemporal walking characteristics such as comfortable walking speed, step length, and double support time, while other spatiotemporal walking characteristics did not change (step parameter symmetry) or change at a significant level (sustained walking speed). The clinical relevance of this study is that participation in therapeutic yoga as a post-rehabilitation wellness activity may have a positive impact on walking characteristics in adults with chronic stroke

随意的な歩行制御が運動後の運動皮質の興奮性変化に与える影響

To explore the effects of qualitative or quantitative changes in walking on motor cortical excitability, a transcranial magnetic stimulation procedure was used to examine the alterations of motor-evoked potential (MEP) amplitude following walking. Eight healthy participants completed a series of two walking tasks on a treadmill at 2 km/h. The ratio of the left stance duration to the right stance duration was 1 : 2 in the asymmetrical walking task and 1 : 1 in the symmetrical walking task. In each task, walking for 10 min followed by MEP measurement for ?4 min was repeated three times. MEP measurements were also performed before a walking task as a baseline and continued every 10 min for a further 30 min after the completion of the walking task. During slight voluntary contraction of the left tibialis anterior muscle, MEP measurements were conducted four times. Although a significant MEP depression was found after the asymmetrical walking task with increasing amount of walking, no significant decrease in MEP below baseline was observed after the symmetrical walking task throughout all measurement sessions. This MEP depression was the prominent response to the asymmetrical walking task compared with the symmetrical walking task. These findings indicate that the intentional control of walking pattern has both temporal and task-specific influences on excitability changes in the cerebral cortex, and suggest that motor cortical excitability may be altered by controlling the amount of central commands to the legs even during gait exercise.広島大学(Hiroshima University)博士(保健学)Philosophy in Health Sciencedoctora

Stride-time variability is related to sensorimotor cortical activation during forward and backward walking

Previous research has used functional near-infrared spectroscopy (fNIRS) to show that motor areas of the cortex are activated more while walking backward compared to walking forward. It is also known that head movement creates motion artifacts in fNIRS data. The aim of this study was to investigate cortical activation during forward and backward walking, while also measuring head movement. We hypothesized that greater activation in motor areas while walking backward would be concurrent with increased head movement. Participants performed forward and backward walking on a treadmill. Participants wore motion capture markers on their head to quantify head movement and pressure sensors on their feet to calculate stride-time. fNIRS was placed over motor areas of the cortex to measure cortical activation. Measurements were compared for forward and backward walking conditions. No significant differences in body movement or head movement were observed between forward and backward walking conditions, suggesting that conditional differences in movement did not influence fNIRS results. Stride-time was significantly shorter during backward walking than during forward walking, but not more variable. There were no differences in activation for motor areas of the cortex when outliers were removed. However, there was a positive correlation between stride-time variability and activation in the primary motor cortex. This positive correlation between motor cortex activation and stride-time variability suggests that forward walking variability may be represented in the primary motor cortex

Treadmill exercise activates subcortical neural networks and improves walking after a stroke

BACKGROUND AND PURPOSE: Stroke often impairs gait thereby reducing mobility and fitness and promoting chronic disability. Gait is a complex sensorimotor function controlled by integrated cortical, subcortical, and spinal networks. The mechanisms of gait recovery after stroke are not well understood. This study examines the hypothesis that progressive task-repetitive treadmill exercise (T-EX) improves fitness and gait function in subjects with chronic hemiparetic stroke by inducing adaptations in the brain (plasticity).METHODS: A randomized controlled trial determined the effects of 6-month T-EX (n=37) versus comparable duration stretching (CON, n=34) on walking, aerobic fitness and in a subset (n=15/17) on brain activation measured by functional MRI.RESULTS: T-EX significantly improved treadmill-walking velocity by 51% and cardiovascular fitness by 18% (11% and -3% for CON, respectively; P<0.05). T-EX but not CON affected brain activation during paretic, but not during nonparetic limb movement, showing 72% increased activation in posterior cerebellar lobe and 18% in midbrain (P<0.005). Exercise-mediated improvements in walking velocity correlated with increased activation in cerebellum and midbrain.CONCLUSIONS: T-EX improves walking, fitness and recruits cerebellum-midbrain circuits, likely reflecting neural network plasticity. This neural recruitment is associated with better walking. These findings demonstrate the effectiveness of T-EX rehabilitation in promoting gait recovery of stroke survivors with long-term mobility impairment and provide evidence of neuroplastic mechanisms that could lead to further refinements in these paradigms to improve functional outcomes

Movement Rehabilitation in Physiotherapy after Stroke: The Role of Constraint-Induced Movement Therapy

Stroke is increasingly becoming a global health problem. This is because it may lead to death, Long-term disability such as in motor function, and significant burden to the patients and their families. The disability can be prevented or rehabilitated using a physiotherapy technique known as constraint-induced movement therapy (CIMT). The CIMT comprises of task practice with the affected limb, constraint of the unaffected limb, and transfer package to foster compliance and increase the amount of task repetition. It helps to reestablish normal motor control through facilitating changes in physiological functions of the brain, improvement in real-world arm use, and movement precision and quality. However, its protocols vary. Some protocols use number of hours and others use number of repetitions to determine the intensity or the amount of task practice. This chapter argued that CIMT is effective, but the protocols that use a number of hours of task practice are not clear and are resource intensive; and as such they could interfere with the process of clinical decision making. Consequently, it proposed the use of a number of repetitions of task practice to determine the intensity or the amount of task practice and extending the application of CIMT to those with severe impairments after stroke

Brain Areas Associated with Force Steadiness and Intensity During Isometric Ankle Dorsiflexion in Men and Women

Although maintenance of steady contractions is required for many daily tasks, there is little understanding of brain areas that modulate lower limb force accuracy. Functional magnetic resonance imaging was used to determine brain areas associated with steadiness and force during static (isometric) lower limb target-matching contractions at low and high intensities. Fourteen young adults (6 men and 8 women; 27.1 ± 9.1 years) performed three sets of 16-s isometric contractions with the ankle dorsiflexor muscles at 10, 30, 50, and 70 % of maximal voluntary contraction (MVC). Percent signal changes (PSCs, %) of the blood oxygenation level-dependent response were extracted for each contraction using region of interest analysis. Mean PSC increased with contraction intensity in the contralateral primary motor area (M1), supplementary motor area, putamen, pallidum cingulate cortex, and ipsilateral cerebellum (p \u3c 0.05). The amplitude of force fluctuations (standard deviation, SD) increased from 10 to 70 % MVC but relative to the mean force (coefficient of variation, CV %) was greatest at 10 % MVC. The CV of force was associated with PSC in the ipsilateral parietal lobule (r = −0.28), putamen (r = −0.29), insula (r = −0.33), and contralateral superior frontal gyrus (r = −0.33, p \u3c 0.05). There were minimal sex differences in brain activation across the isometric motor tasks indicating men and women were similarly motivated and able to activate cortical motor centers during static tasks. Control of steady lower limb contractions involves cortical and subcortical motor areas in both men and women and provides insight into key areas for potential cortical plasticity with impaired or enhanced leg function

Does stroke location predict walk speed response to gait rehabilitation?

Objectives Recovery of independent ambulation after stroke is a major goal. However, which rehabilitation regimen best benefits each individual is unknown and decisions are currently made on a subjective basis. Predictors of response to specific therapies would guide the type of therapy most appropriate for each patient. Although lesion topography is a strong predictor of upper limb response, walking involves more distributed functions. Earlier studies that assessed the cortico-spinal tract (CST) were negative, suggesting other structures may be important. Experimental Design: The relationship between lesion topography and response of walking speed to standard rehabilitation was assessed in 50 adult-onset patients using both volumetric measurement of CST lesion load and voxel-based lesion–symptom mapping (VLSM) to assess non-CST structures. Two functional mobility scales, the functional ambulation category (FAC) and the modified rivermead mobility index (MRMI) were also administered. Performance measures were obtained both at entry into the study (3–42 days post-stroke) and at the end of a 6-week course of therapy. Baseline score, age, time since stroke onset and white matter hyperintensities score were included as nuisance covariates in regression models. Principal Observations: CST damage independently predicted response to therapy for FAC and MRMI, but not for walk speed. However, using VLSM the latter was predicted by damage to the putamen, insula, external capsule and neighbouring white matter. Conclusions Walk speed response to rehabilitation was affected by damage involving the putamen and neighbouring structures but not the CST, while the latter had modest but significant impact on everyday functions of general mobility and gait