Functional electrical stimulation during walking in children with unilateral spastic cerebral palsy: A randomized cross-over trial

AIM

To study if functional electrical stimulation (FES) of the peroneal nerve, which activates dorsiflexion, can improve body functions, activities, and participation and could be an effective alternative treatment in individuals with unilateral spastic cerebral palsy (CP).

METHOD

A randomized cross-over trial was performed in 25 children with unilateral spastic CP (classified in Gross Motor Function Classification System levels I and II) aged 4 to 18 years (median age at inclusion 9 years 8 months, interquartile range = 7 years-13 years 8 months), 15 patients were male. The study consisted of two 12-week blocks of treatment, that is, conventional treatment (ankle foot orthosis [AFO] or adapted shoes) and FES, separated by a 6-week washout period. Outcome measures included the Goal Attainment Scale (GAS), the Cerebral Palsy Quality of Life questionnaire, and a three-dimensional gait analysis.

RESULTS

Eighteen patients completed the trial. The proportion of GAS goals achieved was not significantly higher in the FES versus the conventional treatment phase (goal 1 p = 0.065; goal 2 p = 1.00). When walking while stimulated with FES, ankle dorsiflexion during mid-swing decreased over time (p = 0.006, average decrease of 4.8° with FES), with a preserved increased ankle range of motion compared to conventional treatment (p < 0.001, mean range of motion with FES +10.1° compared to AFO). No changes were found in the standard physical examination or regarding satisfaction with orthoses and feelings about the ability to dress yourself. In four patients, FES therapy failed; in 12 patients FES therapy continued after the trial.

INTERPRETATION

FES is not significantly worse than AFO; however, patient selection is critical, and a testing period and thorough follow-up are needed.

Demonstrating the utility of Instrumented Gait Analysis in the treatment of children with cerebral palsy

BACKGROUND

Instrumented gait analysis (IGA) has been around for a long time but has never been shown to be useful for improving patient outcomes. In this study we demonstrate the potential utility of IGA by showing that machine learning models are better able to estimate treatment outcomes when they include both IGA and clinical (CLI) features compared to when they include CLI features alone.

DESIGN

We carried out a retrospective analysis of data from ambulatory children diagnosed with cerebral palsy who were seen at least twice at our gait analysis center. Individuals underwent a variety of treatments (including no treatment) between sequential gait analyses. We fit Bayesian Additive Regression Tree (BART) models that estimated outcomes for mean stance foot progression to demonstrate the approach. We built two models: one using CLI features only, and one using CLI and IGA features. We then compared the models' performance in detail. We performed similar, but less detailed, analyses for a number of other outcomes. All results were based on independent test data from a 70%/30% training/testing split.

RESULTS

The IGA model was more accurate than the CLI model for mean stance-phase foot progression outcomes (RMSEIGA = 11∘, RMSECLI = 13∘) and explained more than 1.5 × as much of the variance (R2IGA = .45, R2CLI = .28). The IGA model outperformed the CLI model for every level of treatment complexity, as measured by number of simultaneous surgeries. The IGA model also exhibited superior performance for estimating outcomes of mean stance-phase knee flexion, mean stance-phase ankle dorsiflexion, maximum swing-phase knee flexion, gait deviation index (GDI), and dimensionless speed.

INTERPRETATION

The results show that IGA has the potential to be useful in the treatment planning process for ambulatory children diagnosed with cerebral palsy. We propose that the results of machine learning outcome estimators-including estimates of uncertainty-become the primary IGA tool utilized in the clinical process, complementing the standard medical practice of conducting a through patient history and physical exam, eliciting patient goals, reviewing relevant imaging data, and so on.

Effectiveness of Rhythmic Auditory Stimulation on Gait in Parkinson Disease: A Systematic Review and Meta-analysis

Parkinson disease is a neurodegenerative disease present in approximately 2% of the population older than 65 years. Rhythmic auditory stimulation in the early 1990s aimed to improve individual mobility in terms of gait speed, stride length, and cadence. Our systematic review and meta-analysis aimed to summarize and evaluate the evidence of the effects of rhythmic auditory stimulation on gait speed, stride length, and cadence in patients with Parkinson disease. A systematic review and meta-analysis of randomized controlled trials was conducted to determine the efficacy of rhythmic auditory stimulation in patients with Parkinson disease. Five studies were included in the review (209 patients). Rhythmic auditory stimulation resulted, on average, a gait speed improvement of 0.53 standard deviation (SD) units (95% CI, 0.23 to 0.83; P = .0005), a stride length improvement of 0.51 SD units (95% CI, 0.18 to 0.84; P = .003) greater than that in the control group. All trials contained a risk of bias due to a lack of blinding. The quality of evidence was low. No adverse events were identified. Rhythmic auditory stimulation may have a beneficial effect on gait speed and stride length in patients with Parkinson disease. Future studies should consider a power analysis to recruit an adequate number of subjects and minimize the risk of sample bias. Further research should provide the additional results required for an acceptable estimate of the effects of rhythmic auditory stimulation on gait in patients with Parkinson disease.

Analyses of the clinical factors and freezing of gait in association with the quality-of-life indexes in Parkinson's disease subjects with and without STN-DBS therapy

INTRODUCTION

In this research, paying particular attention to freezıng of gait (FOG), we aimed to investigate the associations between the clinical features and quality of lilfe (QOL) indexes comparatively in our PD subjects with and without STN-DBS therapy.

METHODS

All consecutive PD subjects with and without STN-DBS who applied to our movement disorders outpatient clinics between January/2022 and September/2022; and accepted to participate in the study were enrolled. The demographic data and clinical features were noted. Besides, the MDS-UPDRS, the FOG Questionnaire (FOGQ) and the Parkinson's Disease Questionnaire (PDQ-39) have also been performed on all individuals.

RESULTS

Overall, 105 patients with PD participated in this study (34 patients with STN-DBS, 71 patients without STN-DBS). No difference was found in the PDQ-39 scores between patients with and without STN-DBS. The correlation analyses between the PQQ-39 scores and the clinical parameters revealed significant moderate correlations with the FOGQ score and low correlations with MDS-UPDRS scores. The analyses repeated in either patient group showed that there were no correlations between the MDS-UPDRS scores and PDQ-39 indexes in the DBS group. Besides, the correlations between the PDQ-39 scores and the FOG scores were more prominent in patients without DBS therapy.

CONCLUSION

FOG was found to be associated with worse QOL status in both patients with and without STN-DBS therapy. However, the correlations analyses in either group showed that FOG was a more significant determinant in the QOL indexes in patients without DBS. Future studies evaluating the impact of other clinical features such as falls and gait impairment in QOL of patients with STN-DBS may provide contributions to the current evidence.

Another Step Forward for Freezing of Gait in Parkinson's Disease

The study "A spinal cord neuroprosthesis for locomotor deficits due to Parkinson's disease" by Milekovic et al. introduces a novel neuroprosthesis for treating locomotor deficits in late-stage Parkinson's disease (PD). This approach employs an epidural spinal array targeting dorsal roots and electromyography to create a spatiotemporal map of muscle activation, aiming to restore natural gait patterns. Significant improvements in gait freezing and balance were observed in both non-human primate models and a human patient, resulting in improved mobility and quality of life. This innovative method, integrating real-time feedback and non-invasive motor intention decoding, marks a significant advancement in PD treatment.

Soft robotic apparel to avert freezing of gait in Parkinson's disease

Freezing of gait (FoG) is a profoundly disruptive gait disturbance in Parkinson's disease, causing unintended stops while walking. Therapies for FoG reveal modest and transient effects, resulting in a lack of effective treatments. Here we show proof of concept that FoG can be averted using soft robotic apparel that augments hip flexion. The wearable garment uses cable-driven actuators and sensors, generating assistive moments in concert with biological muscles. In this n-of-1 trial with five repeated measurements spanning 6 months, a 73-year-old male with Parkinson's disease and substantial FoG demonstrated a robust response to robotic apparel. With assistance, FoG was instantaneously eliminated during indoor walking (0% versus 39 ± 16% time spent freezing when unassisted), accompanied by 49 ± 11 m (+55%) farther walking compared to unassisted walking, faster speeds (+0.18 m s-1) and improved gait quality (-25% in gait variability). FoG-targeting effects were repeatable across multiple days, provoking conditions and environment contexts, demonstrating potential for community use. This study demonstrated that FoG was averted using soft robotic apparel in an individual with Parkinson's disease, serving as an impetus for technological advancements in response to this serious yet unmet need.

Cortical Disinhibition Drives Freezing of Gait in Parkinson's Disease and an Exploratory Repetitive Transcranial Magnetic Stimulation Study

BACKGROUND

Dysfunction of the primary motor cortex, participating in regulation of posture and gait, is implicated in freezing of gait (FOG) in Parkinson's disease (PD).

OBJECTIVE

The aim was to reveal the mechanisms of "OFF-period" FOG (OFF-FOG) and "levodopa-unresponsive" FOG (ONOFF-FOG) in PD.

METHODS

We measured the transcranial magnetic stimulation (TMS) indicators and gait parameters in 21 healthy controls (HCs), 15 PD patients with ONOFF-FOG, 15 PD patients with OFF-FOG, and 15 PD patients without FOG (Non-FOG) in "ON" and "OFF" medication conditions. Difference of TMS indicators in the four groups and two conditions and its correlations with gait parameters were explored. Additionally, we explored the effect of 10 Hz repetitive TMS on gait and TMS indicators in ONOFF-FOG patients.

RESULTS

In "OFF" condition, short interval intracortical inhibition (SICI) exhibited remarkable attenuation in FOG patients (both ONOFF-FOG and OFF-FOG) compared to Non-FOG patients and HCs. The weakening of SICI correlated with impaired gait characteristics in FOG. However, in "ON" condition, SICI in ONOFF-FOG patients reduced compared to OFF-FOG patients. Pharmacological treatment significantly improved SICI and gait in OFF-FOG patients, and high-frequency repetitive TMS distinctly improved gait in ONOFF-FOG patients, accompanied by enhanced SICI.

CONCLUSIONS

Motor cortex disinhibition, represented by decreased SICI, is related to FOG in PD. Refractory freezing in ONOFF-FOG patients correlated with the their reduced SICI insensitive to dopaminergic medication. SICI can serve as an indicator of the severity of impaired gait characteristics in FOG and reflect treatments efficacy for FOG in PD patients. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

A spinal cord neuroprosthesis for locomotor deficits due to Parkinson's disease

People with late-stage Parkinson's disease (PD) often suffer from debilitating locomotor deficits that are resistant to currently available therapies. To alleviate these deficits, we developed a neuroprosthesis operating in closed loop that targets the dorsal root entry zones innervating lumbosacral segments to reproduce the natural spatiotemporal activation of the lumbosacral spinal cord during walking. We first developed this neuroprosthesis in a non-human primate model that replicates locomotor deficits due to PD. This neuroprosthesis not only alleviated locomotor deficits but also restored skilled walking in this model. We then implanted the neuroprosthesis in a 62-year-old male with a 30-year history of PD who presented with severe gait impairments and frequent falls that were medically refractory to currently available therapies. We found that the neuroprosthesis interacted synergistically with deep brain stimulation of the subthalamic nucleus and dopaminergic replacement therapies to alleviate asymmetry and promote longer steps, improve balance and reduce freezing of gait. This neuroprosthesis opens new perspectives to reduce the severity of locomotor deficits in people with PD.

Upregulation of the parietal cortex improves freezing of gait in Parkinson's disease

BACKGROUND The posterior parietal cortex (PPC) is a key brain area for visuospatial processing and locomotion. It has been repetitively shown to be involved in the neural correlates of freezing of gait (FOG), a common symptom of Parkinson's disease (PD). However, current neuroimaging modalities do not allow to precisely determine the role of the PPC during real FOG episodes. OBJECTIVES The purpose of this study was to modulate the PPC cortical excitability using repetitive transcranial magnetic stimulation (rTMS) to determine whether the PPC contributes to FOG or compensates for dysfunctional neural networks to reduce FOG. METHODS Fourteen participants with PD who experience freezing took part in a proof of principle study consisting of three experimental sessions targeting the PPC with inhibitory, excitatory, and sham rTMS. Objective FOG outcomes and cortical excitability measurements were acquired before and after each stimulation protocol. RESULTS Increasing PPC excitability resulted in significantly fewer freezing episodes and percent time frozen during a FOG-provoking task. This reduction in FOG most likely emerged from the trend in PPC inhibiting the lower leg motor cortex excitability. CONCLUSION Our results suggest that the recruitment of the PPC is linked to less FOG, providing support for the beneficial role of the PPC upregulation in preventing FOG. This could potentially be linked to a reduction of the cortical input burden on the basal ganglia prior to FOG. Excitatory rTMS interventions targeting the PPC may have the potential to reduce FOG.

Smart ankle bracelet-laser device to improve gait and detect freezing of gait in Parkinsonism patients: a case series

Freezing of gait (FOG) is one of the most disabling symptoms of Parkinsonism. Moreover, it does not respond well to medication. Visual cues have been shown to alleviate FOG in Parkinsonism; however, their efficacy is inconsistent. Currently, most mobile cueing devices are used as an open-loop cueing system, which requires manual control to enable constant visual cues. Thus, such devices may not be suitable for some people, especially those who have attention deficits. In addition, objective measurements of FOG in real-life situations remain challenging. Therefore, we developed a smart-ankle laser as a closed-loop cueing system that can detect the patient's walking pattern and automatically project a laser line that follows each walking step, thus requires less attention. Real-time motion was also recorded within the device for FOG measurement. We studied the efficacy of the device in three Parkinsonism patients with FOG (one man and two women, aged 58-76 years) immediately after use and two patients at 1-week follow-up. Gait speed, Timed Up and Go test performance, stride length, and % FOG improved with the use of the laser, without adverse effects.

Three-dimensional gait analysis of the effect of directional steering on gait in patients with Parkinson's disease

INTRODUCTION

Deep Brain Stimulation (DBS) is an option to treat advanced Parkinson's Disease (PD), but can cause gait disturbance due to stimulation side efffects. This study aims to evaluate the objective effect of directional current steering by DBS on gait performance in PD, utilizing a three-dimensional gait analysis system.

METHODS

Eleven patients diagnosed with PD and were implanted with directional lead were recruited. The direction of the pyramidal tract (identified by the directional mode screening) was set as 0°. Patients performed the six-meter-walk test and the time up-and-go (TUG) test while an analysis system recorded gait parameters utilizing a three-dimensional motion capture camera. The gait parameters were measured for the baseline, the directional steering at eight angles (0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°), and the conventional ring mode with 1, 2, and 3 mA. Pulse width and frequency were fixed. Placebo stimulation (0 mA) was used for a control.

RESULTS

Eleven patients completed the study. No significant difference were observed between gait parameters during the directional, baseline, placebo, or ring modes during the six-meter-walk test (p > 0.05). During the TUG test, stride length was significantly different between 0° and other directions (p < 0.001), but no significant differences were observed for the other gait parameters. Stride width was non-significantly narrower in the direction of 0°.

CONCLUSION

Controlling stimulation using directional steering may improve gait in patients with PD, while avoiding pyramidal side effects.

Effects of Exercise-based Management on Motor Symptoms in Parkinson's Disease - A Meta-analysis

Parkinson's disease (PD) is the second most common neurological illness after Alzheimer's disease. According to research, medication alone can give palliative alleviation; however, freezing of gait (FOG) and balance can be treated with physical therapy. This meta-analysis aims to bridge gaps about exercise-based therapy's impact on balance and FOG in patients with PD. Google Scholar, CINHAL, Medline, PubMed, and PEDro were searched for 2016-2021 citations using the PIOD paradigm. Pooled effect size mean and SD were analysed using a fixed and random effects model. A total of 21 trials were included in this review, with SMD=0.60 and p=0.0007 utilising BBS. The pooled analysis revealed statistically significant impacts on exercise-based management in the experimental group. With SMD=0.87 and p<0.00001 using Mini-BESTest, the pooled analysis revealed that exercise-based management was also effective on balance in the experimental group. The fixed effect model of FOG in terms of SMD was used to draw the pooled effects of FOG in terms of SMD and FOG in terms of SMD (0.21; 95 percent CI -0.01 to 0.44; p=0.06). According to this research, several physiotherapy approaches such as exergaming, gamepad systems, virtual reality, gait exercises, and core training, help Parkinson's patients regain balance and FOG. Key Words: Parkinson's disease, Physical therapy techniques, Neurological rehabilitation, Balance, Freezing of gait, Motor symptoms.

A systematic literature review of ankle-foot orthosis and functional electrical stimulation foot-drop treatments for persons with multiple sclerosis

Foot-drop is one of the most diagnosed and physically limiting symptoms persons with multiple sclerosis (pwMS) experience. Clinicians prescribe ankle-foot orthosis (AFO) and functional electrical stimulation (FES) devices to help alleviate the effects of foot drop, but it is unclear how their clinical and functional gait improvements compare given the user's level of disability, type of multiple sclerosis, walking environment, or desired physical activity. The research questions explored were what is the current state of AFO and FES research for pwMS? What are the prevailing research trends? What definitive clinical and functional device comparisons exist for pwMS? eight databases were systematically searched for relevant literature published between 2009 and 2021. The American Association of Orthotists and Prosthetists and Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines for systematic literature reviews were followed. A team of 3 researchers critically evaluated 17 articles that passed eligibility criteria. This review discusses the current state and trends of research, provides evidence statements on device effects, and recommends improvements for future studies. A meta-analysis would be informative, but study variability across the literature makes directly comparing AFO and FES device effects unreliable. This review contributes new and useful information to multiple sclerosis literature that can be used by both clinicians and researchers. Clinicians can use the provided insights to prescribe more effective, customized treatments, and other researchers can use them to evaluate and design future studies.

Subthalamic Nucleus Activity during Cognitive Load and Gait Dysfunction in Parkinson's Disease

BACKGROUND

Gait freezing is a common, disabling symptom of Parkinson's disease characterized by sudden motor arrest during walking. Adaptive deep brain stimulation devices that detect freezing and deliver real-time, symptom-specific stimulation are a potential treatment strategy. Real-time alterations in subthalamic nucleus firing patterns have been demonstrated with lower limb freezing, however, whether similar abnormal signatures occur with freezing provoked by cognitive load, is unknown.

METHODS

We obtained subthalamic nucleus microelectrode recordings from eight Parkinson's disease patients performing a validated virtual reality gait task, requiring responses to on-screen cognitive cues while maintaining motor output.

RESULTS

Signal analysis during 15 trials containing freezing or significant motor output slowing precipitated by dual-tasking demonstrated reduced θ frequency (3-8 Hz) firing compared to 18 unaffected trials.

CONCLUSIONS

These preliminary results reveal a potential neurobiological basis for the interplay between cognitive factors and gait disturbances including freezing in Parkinson's disease, informing development of adaptive deep brain stimulation protocols. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Spinal cord stimulation for gait disturbances in Parkinson's disease

INTRODUCTION

Gait disturbances are a major contributor to the disability associated with Parkinson's disease. Although pharmacologic therapies and deep brain stimulation improve most motor parkinsonian features, their effects on gait are highly variable. Spinal cord stimulation, typically used for the treatment of chronic pain, has emerged as a potential therapeutic approach to improve gait disturbances in Parkinson's disease.

AREAS COVERED

The authors review the available evidence on the effects of spinal cord stimulation in patients with Parkinson's disease, targeting primarily gait abnormalities. They also discuss possible mechanisms, safety, and methodological implications for future clinical trials. This systematic review of originally published articles in English language was performed using The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA).

Spinal Cord Stimulation for Gait Disorders in Parkinson's Disease

BACKGROUND

Spinal cord stimulation (SCS) is a therapeutic procedure widely used in the management of refractory chronic pain. Evidence from case reports and small descriptive studies has emerged suggesting a role for SCS in patients with gait dysfunction, such as freezing of gait (FoG) and postural imbalance. These are severely debilitating symptoms of advanced Parkinson's disease (PD).

OBJECTIVE

To establish the current evidence base for the potential application of SCS on gait and balance dysfunction in PD patients.

METHODS

Three online databases were screened for relevant manuscripts. Two separate searches and four different search strategies were applied to yield relevant results. The main parameters of interest were postural and gait symptoms; secondary outcomes were Quality of Life (QoL) and adverse effects.

RESULTS

Nineteen studies fulfilled the inclusion criteria. Motor improvements using section III of the Unified Parkinson's Disease Rating Score (UPDRS-III) were available in 13 studies. Measurements to assess FoG reported the following improvements: FoG questionnaires (in 1/19 studies); generalized freezing parameters (2); and walkway/wireless accelerometer measurements (2). Parameters of postural imbalance and falling improved as follows: BBS (1); posture sagittal vertical axis (1); and generalized data on postural instability (8). Two studies reported on adverse effects. QoL was shown to improve as follows: EQ-5D (2); ADL (1); SF-36 (1); BDI-II (1); PDQ-8 (1); HDRS (1); and VAS (5).

CONCLUSION

SCS may have a therapeutic potential in advanced PD patients suffering from postural and gait-related symptoms. The existing evidence suggests that SCS positively affects patients' QoL with an acceptable safety profile in this patient population.

Effects of a lower limb rehabilitation robot with various training modes in patients with stroke: A randomized controlled trial

BACKGROUND

The effect of robot-assisted gait training has been demonstrated to improve gait recovery in patients with stroke. The aim of this study was to determine effects of robot-assisted gait training with various training modes in patients post stroke.

METHODS

Forty-seven patients post stroke were randomly assigned to one of 4 groups: Healbot T with pelvic off mode (pelvic off group; n = 11); Healbot T with pelvic control mode (pelvic on group; n = 12); Healbot T with constraint-induced movement therapy (CIMT) mode (CIMT group; n = 10); and conventional physiotherapy (control group; n = 10). All patients received a 30-minute session 10 times for 4 weeks. The primary outcomes were the 10-meter walk test (10MWT) and Berg Balance Scale (BBS). The secondary outcomes were functional ambulation category, timed up and go (TUG), and motricity index of the lower extremities (MI-Lower).

RESULTS

The pelvic off group showed significant improvements in BBS, TUG, and MI-Lower (P < .05). The pelvic on and CIMT groups showed significant improvement in 10MWT, BBS, TUG, and MI-Lower (P < .05). Compared with control group, the pelvic on group showed greater improvement in the TUG and BBS scores; the CIMT group showed greater improvement in 10MWT and MI-Lower (P < .05).

CONCLUSION

This study suggested that Healbot T-assisted gait training benefited patients with stroke. The Healbot T with pelvic motion and CIMT modes were more helpful in improving balance and walking ability and lower limb strength, respectively, compared with conventional physiotherapy.

Research Progress of Music Therapy on Gait Intervention in Patients with Parkinson’s Disease

Music therapy is an effective way to treat the gait disorders caused by Parkinson’s disease. Rhythm music stimulation, therapeutic singing, and therapeutic instrument performance are often used in clinical practice. The mechanisms of music therapy on the gait of patients with Parkinson’s disease include the compensation mechanism of cerebellum recruitment, rhythm entrainment, acceleration of motor learning, stimulation of neural coherence, and increase of cortical activity. All mechanisms work together to complete the intervention of music therapy on patients’ gait and help patients to recover better. In this paper, the effect of music therapy on gait disorders in Parkinson’s disease patients was reviewed, and some suggestions were put forward.

A 6-Month Home-Based Functional Electrical Stimulation Program for Foot Drop in a Post-Stroke Patient: Considerations on a Time Course Analysis of Walking Performance

Foot drop is a common disability in post-stroke patients and represents a challenge for the clinician. To date, ankle foot orthosis (AFO) combined with conventional rehabilitation is the gold standard of rehabilitation management. AFO has a palliative mechanical action without actively restoring the associated neural function. Functional electrical stimulation (FES), consisting of stimulation of the peroneal nerve pathway, represents an alternative approach. By providing an FES device (Bioness L-300, BIONESS, Valencia, CA, USA) for 6 months to a post-stroke 22-year-old woman with a foot drop, our goal was to quantify its potential benefit on walking capacity. The gait parameters and the temporal evolution of the speed were collected with a specific connected sole device (Feet Me^®) during the 10-m walking, the time up and go, and the 6-minute walking tests with AFO, FES, or without any device (NO). As a result, the walking speed changes on 10-m were clinically significant with an increase from the baseline to 6 months in AFO (+0.14 m.s⁻¹), FES (+0.36 m.s⁻¹) and NO (+0.32 m.s⁻¹) conditions. In addition, the speed decreased at about 4-min in the 6-minute walking test in NO and AFO conditions, while the speed increased in the FES conditions at baseline and after 1, 3, and 6 months. In addition to the walking performance improvement, monitoring the gait speed in an endurance test after an ecological rehabilitation training program helps to examine the walking performance in post-stroke patients and to propose a specific rehabilitation program.

Managing freezing of gait in Parkinson's disease: a systematic review and network meta-analysis

BACKGROUND

Freezing of gait (FOG) is one of the most disabling gait disorders affecting 80% of patients with Parkinson's disease (PD). Clinical guidelines recommend a behavioral approach for gait rehabilitation, but there is a wide diversity of behavioral modalities.

OBJECTIVE

The objective of this network meta-analysis was to compare the effectiveness of different behavioral interventions for FOG management in PD patients.

METHODS

Six databases were searched for randomized controlled trials of behavioral interventions for FOG management among PD patients from 1990 to December 2021. Bayesian network meta-analysis was used to combine both direct and indirect trial evidence on treatment effectiveness, while the surface under the cumulative ranking (SUCRA) score was used to estimate the ranked probability of intervention effectiveness.

RESULTS

Forty-six studies were included in the qualitative synthesis. Among, 36 studies (1454 patients) of 72 interventions or control conditions (12 classes) were included in the network meta-analysis, with a mean intervention period of 10.3 weeks. After adjusting for the moderating effect of baseline FOG severity, obstacle training [SMD -2.1; 95% credible interval (Crl): -3.3, -0.86], gait training with treadmill (SMD -1.2; 95% Crl: -2.0, -0.34), action observation training (SMD -1.0; 95% Crl: -1.9, -0.14), conventional physiotherapy (SMD -0.70; 95% Crl: -1.3, -0.12) and general exercise (SMD -0.64; 95% Crl: -1.2, -0.11) demonstrated significant improvement on immediate FOG severity compared to usual care. The SUCRA rankings suggest that obstacle training, gait training on treadmill and general exercises are most likely to reduce FOG severity.

CONCLUSION

Obstacle training, gait training on treadmill, general exercises, action observation training and conventional physiotherapy demonstrated immediate real-life benefits on FOG symptoms among patients with mild-moderate PD. With the promising findings, the sustained effects of high complexity motor training combined with attentional/cognitive strategy should be further explored. Future trials with rigorous research designs using both subjective and objective outcome measures, long-term follow-up and cost-effective analysis are warranted to establish effective behavioral strategies for FOG management.

Preliminary Study of Vibrotactile Feedback during Home-Based Balance and Coordination Training in Individuals with Cerebellar Ataxia

Intensive balance and coordination training is the mainstay of treatment for symptoms of impaired balance and mobility in individuals with hereditary cerebellar ataxia. In this study, we compared the effects of home-based balance and coordination training with and without vibrotactile SA for individuals with hereditary cerebellar ataxia. Ten participants (five males, five females; 47  ±  12 years) with inherited forms of cerebellar ataxia were recruited to participate in a 12-week crossover study during which they completed two six-week blocks of balance and coordination training with and without vibrotactile SA. Participants were instructed to perform balance and coordination exercises five times per week using smartphone balance trainers that provided written, graphic, and video guidance and measured trunk sway. The pre-, per-, and post-training performance were assessed using the Scale for the Assessment and Rating of Ataxia (SARA), SARAposture&gait sub-scores, Dynamic Gait Index, modified Clinical Test of Sensory Interaction in Balance, Timed Up and Go performed with and without a cup of water, and multiple kinematic measures of postural sway measured with a single inertial measurement unit placed on the participants’ trunks. To explore the effects of training with and without vibrotactile SA, we compared the changes in performance achieved after participants completed each six-week block of training. Among the seven participants who completed both blocks of training, the change in the SARA scores and SARAposture&gait sub-scores following training with vibrotactile SA was not significantly different from the change achieved following training without SA (p>0.05). However, a trend toward improved SARA scores and SARAposture&gait sub-scores was observed following training with vibrotactile SA; compared to their pre-vibrotacile SA training scores, participants significantly improved their SARA scores (mean=−1.21, p=0.02) and SARAposture&gait sub-scores (mean=−1.00, p=0.01). In contrast, no significant changes in SARA scores and SARAposture&gait sub-scores were observed following the six weeks of training without SA compared to their pre-training scores immediately preceding the training block without vibrotactile SA (p>0.05). No significant changes in trunk kinematic sway parameters were observed as a result of training (p>0.05). Based on the findings from this preliminary study, balance and coordination training improved the participants’ motor performance, as captured through the SARA. Vibrotactile SA may be a beneficial addition to training regimens for individuals with hereditary cerebellar ataxia, but additional research with larger sample sizes is needed to assess the significance and generalizability of these findings.

On the benefits of wearable devices for Parkinson's disease

Freezing of gait (FOG) is defined as episodic inability to generate an effective movement without any known cause other than parkinson-ism or gait disturbance. FOG is one of the most disabling symptoms of Parkinson's disease (PD), it affects mobility and increases the risk of falling in people with PD, making it a leading cause of hospitalization and of significantly worsening the quality of life (1). In recent years, new non-invasive intervention strategies have been implemented to decrease FOG symptoms. Thanks to technological progress, several devices have been developed as a support for the patients during diag-nosis, treatments and also everyday life. These types of interventions are based on cueing systems that rely on active stimulation. These devices are able to identify FOG states and to operate when this motor blocks occur, providing external stimuli to overcome these episodes. Hence, this work aims to provide a technological review of the literature related to wearable devices and focuses on auditory, visual, virtual and soma-tosensory cueing systems, which can provide a suitable intervention for patients with PD. The paper describes the technical functioning and effectiveness of the different reporting systems in overcoming FOG episodes. Moreover, a classification of existing devices, highlighting their advantages and disadvantages, will be provided in order to identify the ones with the best performance.

Efficacy of caudal pedunculopontine nucleus stimulation on postural instability and gait disorders in Parkinson's disease

OBJECTIVES

Gait-related symptoms like postural instability and gait disorders (PIGD) inexorably worsen with Parkinson's disease (PD) deterioration and become refractory to current available medical treatment and deep brain stimulation (DBS) of conventional targets. Pedunculopontine nucleus (PPN) deep brain stimulation (DBS) is a promising method to treat PIGD. This prospective study aimed to clarify the clinical application of PPN-DBS and to explore effects of caudal PPN stimulation on PIGD.

METHODS

Five consecutive PD patients with severe medication-resistant postural instability and gait disorders accepted caudal PPN-DBS. LEAD-DBS toolbox was used to reconstruct and visualize the electrodes based on pre- and postoperative images. Outcomes were assessed with Movement Disorder Society (MDS)-Sponsored Revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS), gait-specific questionnaires, and objective gait analysis with GAITRite system.

RESULTS

MDS-UPDRS subitems 35-38 scores were improved at postoperative 6 months (mean, 4.40 vs 11.00; p = 0.0006) and 12 months (mean, 5.60 vs 11.00; p = 0.0013) compared with baseline, and scores at 6 months were slightly lower than scores at 12 months (mean, 4.40 vs 5.60; p = 0.0116). Gait and Falls Questionnaire, New Freezing of Gait Questionnaire, and Falls Questionnaire scores also significantly improved at postoperative 6 months and 12 months compared with baseline. In addition, cadence, bilateral step length, and bilateral stride length significantly increased when PPN On-stimulation compared with Off-stimulation.

CONCLUSIONS

This study suggested that caudal PPN low-frequency stimulation improved PIGD for PD patients at the 6- and 12-month period.

OUP accepted manuscript

Freezing of gait is a debilitating symptom in advanced Parkinson’s disease and responds heterogeneously to treatments such as deep brain stimulation. Recent studies indicated that cortical dysfunction is involved in the development of freezing, while evidence depicting the specific role of the primary motor cortex in the multi-circuit pathology of freezing is lacking. Since abnormal beta-gamma phase-amplitude coupling recorded from the primary motor cortex in patients with Parkinson’s disease indicates parkinsonian state and responses to therapeutic deep brain stimulation, we hypothesized this metric might reveal unique information on understanding and improving therapy for freezing of gait.

Here, we directly recorded potentials in the primary motor cortex using subdural electrocorticography and synchronously captured gait freezing using optoelectronic motion-tracking systems in 16 freely-walking patients with Parkinson’s disease who received subthalamic nucleus deep brain stimulation surgery. Overall, we recorded 451 timed up-and-go walking trials and quantified 7073 s of stable walking and 3384 s of gait freezing in conditions of on/off-stimulation and with/without dual-tasking.

We found that (i) high beta-gamma phase-amplitude coupling in the primary motor cortex was detected in freezing trials (i.e. walking trials that contained freezing), but not non-freezing trials, and the high coupling in freezing trials was not caused by dual-tasking or the lack of movement; (ii) non-freezing episodes within freezing trials also demonstrated abnormally high couplings, which predicted freezing severity; (iii) deep brain stimulation of subthalamic nucleus reduced these abnormal couplings and simultaneously improved freezing; and (iv) in trials that were at similar coupling levels, stimulation trials still demonstrated lower freezing severity than no-stimulation trials.

These findings suggest that elevated phase-amplitude coupling in the primary motor cortex indicates higher probabilities of freezing. Therapeutic deep brain stimulation alleviates freezing by both decoupling cortical oscillations and enhancing cortical resistance to abnormal coupling. We formalized these findings to a novel ‘bandwidth model,’ which specifies the role of cortical dysfunction, cognitive burden and therapeutic stimulation on the emergence of freezing. By targeting key elements in the model, we may develop next-generation deep brain stimulation approaches for freezing of gait.

Structural Connectivity of Subthalamic Nucleus Stimulation for Improving Freezing of Gait

BACKGROUND

Freezing of gait (FOG) is among the most common and disabling symptoms of Parkinson's disease (PD). Studies show that deep brain stimulation (DBS) of the subthalamic nucleus (STN) can reduce FOG severity. However, there is uncertainty about pathways that need to be modulated to improve FOG.

OBJECTIVE

To investigate whether STN-DBS effectively reduces FOG postoperatively and whether structural connectivity of the stimulated tissue explains variance of outcomes.

METHODS

We investigated 47 patients with PD and preoperative FOG. Freezing prevalence and severity was primarily assessed using the Freezing of Gait Questionnaire (FOG-Q). In a subset of 18 patients, provoked FOG during a standardized walking course was assessed. Using a publicly available model of basal-ganglia pathways we determined stimulation-dependent connectivity associated with postoperative changes in FOG. A region-of-interest analysis to a priori defined mesencephalic regions was performed using a disease-specific normative connectome.

RESULTS

Freezing of gait significantly improved six months postoperatively, marked by reduced frequency and duration of freezing episodes. Optimal stimulation volumes for improving FOG structurally connected to motor areas, the prefrontal cortex and to the globus pallidus. Stimulation of the lenticular fasciculus was associated with worsening of FOG. This connectivity profile was robust in a leave-one-out cross-validation. Subcortically, stimulation of fibers crossing the pedunculopontine nucleus and the substantia nigra correlated with postoperative improvement.

CONCLUSION

STN-DBS can alleviate FOG severity by modulating specific pathways structurally connected to prefrontal and motor cortices. More differentiated FOG assessments may allow to differentiate pathways for specific FOG subtypes in the future.

Factors correlated with therapeutic effects of globus pallidus deep brain stimulation on freezing of gait in advanced Parkinson's disease: A pilot study

INTRODUCTION

Deep brain stimulation (DBS) has showed variable therapeutic effect on freezing of gait (FOG) in Parkinson's disease (PD). It is unclear which factors associated with the effect of DBS on FOG in patients with advanced PD. In this study, we investigated the correlation of pre and postoperative factors with the therapeutic effect of globus pallidus interna (GPi) DBS on FOG in PD patients.

METHODS

We retrospectively analyzed PD patients with FOG (N = 20) who underwent GPi DBS surgery. Postoperatively, video-based analysis for FOG severity was performed at the first DBS programming and patients were categorized into two groups according to DBS effect on FOG (11 FOG responders and 9 FOG non-responders) at medication-off state. We analyzed preoperative clinical characteristics, cognitive function, striatal dopamine transporter availability, postoperative DBS programming parameters, lead locations, and volume of tissue activated in functional subregions of GPi. Bootstrap enhanced Elastic-Net logistic regression was used to select pre and postoperative factors associated with the effect of GPi DBS.

RESULTS

Therapeutic effect of GPi DBS on FOG were correlated with the disease duration of PD before DBS surgery, preoperative improvement in FOG severity by levodopa medication, and the distance from active contact of DBS electrode to the prefrontal region of GPi anatomical site.

CONCLUSIONS

Our study results suggest that the effect of GPi DBS on FOG is correlated with disease duration, levodopa responsiveness on FOG before DBS surgery and DBS electrode location, providing useful information to predict FOG outcome after GPi DBS in PD patients.

The Effect of Transcranial Direct Current Stimulation Combined with Visual Cueing Training on Motor Function, Balance, and Gait Ability of Patients with Parkinson's Disease

Background and Objectives: The purpose of this study was to investigate the effects of transcranial direct current stimulation (tDCS) on motor function, balance and gait ability in patients with Parkinson’s disease (PD). Materials and Methods: For the experiment, 30 patients with PD were randomly assigned to the experimental group (n = 15) and the control group (n = 15). Visual cueing training was commonly applied to both groups, the experimental group applied tDCS simultaneously with visual training, and the control group applied sham tDCS simultaneously with visual training. All subjects were pre-tested before the first intervention, post-tested after completing all 4 weeks of intervention, and followed-up tested 2 weeks after the completing intervention. The tests used the Unified Parkinson’s Disease Rating Scale (UPDRS) for motor function assessment, Functional Gait Assessment (FGA) for balance assessment, Freezing of Gait Questionnaire (FOG-Q) and the GAITRite system for gait ability assessment. Among the data obtained through the GAITRite system, gait velocity, cadence, step time, double support time, and stride length were analyzed. Results: The experimental group showed a significant decrease in UPDRS and a significant increase in FGA and cadence after the intervention. In addition, UPDRS and cadence showed a significant difference in the follow-up test compared to the pre-intervention test. Conclusions: This study suggests that the application of tDCS to the supplementary motor area of PD patients is useful as an adjuvant therapy for rehabilitation training of PD patients.

A pilot randomized controlled trial examining the benefits of an adjuvant psycho-behavioural intervention in comparison to a health education program, on psychological well-being and freezing-of-gait in patients with Parkinson's disease

This study investigated the effectiveness of a psycho-behavioural intervention (PBI) for freezing of gait (FOG) management in people with Parkinson's disease, through a double-blind randomized controlled pilot trial conducted with nineteen participants. Though no significant between-group differences were found, PBI was feasible, well-tolerated by participants, and exhibited a trend towards improvement for FOG and depression, thereby warranting further longitudinal investigations.

Freezing of Gait in Parkinson's Disease: Invasive and Noninvasive Neuromodulation

INTRODUCTION

Freezing of gait (FoG) is one of the most disabling yet poorly understood symptoms of Parkinson's disease (PD). FoG is an episodic gait pattern characterized by the inability to step that occurs on initiation or turning while walking, particularly with perception of tight surroundings. This phenomenon impairs balance, increases falls, and reduces the quality of life.

MATERIALS AND METHODS

Clinical-anatomical correlations, electrophysiology, and functional imaging have generated several mechanistic hypotheses, ranging from the most distal (abnormal central pattern generators of the spinal cord) to the most proximal (frontal executive dysfunction). Here, we review the neuroanatomy and pathophysiology of gait initiation in the context of FoG, and we discuss targets of central nervous system neuromodulation and their outcomes so far. The PubMed database was searched using these key words: neuromodulation, freezing of gait, Parkinson's disease, and gait disorders.

CONCLUSION

Despite these investigations, the pathogenesis of this process remains poorly understood. The evidence presented in this review suggests FoG to be a heterogenous phenomenon without a single unifying pathologic target. Future studies rigorously assessing targets as well as multimodal approaches will be essential to define the next generation of therapeutic treatments.

Potential Non-invasive Brain Stimulation Targets to Alleviate Freezing of Gait in Parkinson's Disease

Freezing of gait (FOG) is a common motor symptom in Parkinson's disease (PD). Although FOG reduces quality of life, affects mobility and increases the risk of falls, there are little to no effective treatments to alleviate FOG. Non-invasive brain stimulation (NIBS) has recently yielded attention as a potential treatment to reduce FOG symptoms however, stimulation parameters and protocols remain inconsistent and require further research. Specifically, targets for stimulation require careful review. Thus, with current neuroimaging and neuro-electrophysiological evidence, we consider potential cortical targets thought to be involved in the pathophysiology of FOG according to the Interference model, and within reach of NIBS. We note that the primary motor cortex, the supplementary motor area and the dorsolateral prefrontal cortex have already drawn attention as NIBS targets for FOG, but based on neuroimaging evidence the premotor cortex, the medial prefrontal cortex, the cerebellum, and more particularly, the posterior parietal cortex should be considered as potential regions for stimulation. We also discuss different methodological considerations, such as stimulation type, medication state, and hemisphere to target, and future perspectives for NIBS protocols in FOG.

Immediate effects of treadmill walking in individuals with Lewy body dementia and Huntington's disease

BACKGROUND

Treadmill training may improve gait disorders associated with neurodegenerative diseases. In Parkinson's disease (PD), treadmill training alters gait patterns after one session, and long-term training improves gait parameters, fall risk, and quality of life.

RESEARCH QUESTION

What is the feasibility and safety of using this intervention for people with Lewy body dementia (LBD) or Huntington's disease (HD)?

METHODS

In this observational study, 10 individuals with HD, 8 individuals with LBD, and 10 control individuals walked for 20 min on a treadmill using a speed dependent protocol starting at a slow comfortable speed and increasing incrementally toward their normal overground speed. Feasibility was determined by compliance to protocol and safety by no incidents of abnormal vital signs or expressions of distress. Changes in gait measures, Timed Up and Go (TUG) scores and quantitative motor function measures (Q-Motor; precision grasp force variability, finger and foot tapping frequency) before and after treadmill walking were analyzed using linear models.

RESULTS

Treadmill training is feasible and safe in LBD and HD; although, participants could not initiate treadmill walking at their comfortable overground speeds, and only 3 participants with HD were able to achieve their overground walking speed within the 20-minute session. No changes in gait measures, TUG times, and Q-Motor measures were found among LBD and HD participants after treadmill walking, although control participants demonstrated significant increases in several gait measures, and foot tap frequency (estimated difference = 0.290; p = 0.026).

SIGNIFICANCE

Longer and more frequent treadmill sessions may be needed to see gait and motor function effects in LBD and HD. Motor and cognitive impairments associated with these diseases may make them less amenable to the effects of treadmill training.

Foot ulcer recurrence, plantar pressure and footwear adherence in people with diabetes and Charcot midfoot deformity: A cohort analysis

AIMS

To investigate people with Charcot midfoot deformity with regard to plantar pressure, footwear adherence and plantar foot ulcer recurrence.

METHODS

Twenty people with diabetes, Charcot midfoot deformity, plantar foot ulcer history and custom-made footwear were assessed with regard to barefoot and in-shoe plantar pressures during walking, footwear adherence (% of daily steps over 7-day period) and plantar foot ulcer recurrence over 18 months. In a cohort design, they were compared to 118 people without Charcot foot (non-Charcot foot group) with custom-made footwear and similar ulcer risk factors.

RESULTS

Median (interquartile range) barefoot midfoot peak pressures were significantly higher in the Charcot foot group than in the non-Charcot foot group [756 (260-1267) vs 146 (100-208) kPa; P<0.001]. In-shoe midfoot peak pressures were not significantly higher in the Charcot foot group [median (interquartile range) 152 (104-201) vs 119 (94-160) kPa] and significantly lower for all other foot regions. Participants in the Charcot foot group were significantly more adherent, especially at home, than participants in the non-Charcot foot group [median (interquartile range) 94.4 (85.4-95.0)% vs. 64.3 (25.4-85.7)%; P=0.001]. Ulcers recurred in 40% of the Charcot foot group and in 47% of the non-Charcot foot group (P=0.63); midfoot ulcers recurred significantly more in the Charcot foot group (4/8) than in the non-Charcot foot group (1/55; P=0.001).

CONCLUSIONS

Effective offloading and very high footwear adherence were found in people with diabetes and Charcot midfoot deformity. While this may help protect against plantar foot ulcer recurrence, a large proportion of such people still experience ulcer recurrence. Further improvements in adherence and custom-made footwear design may be required to improve clinical outcome.

Effect of robot-assisted gait training on gait automaticity in Parkinson disease: A prospective, open-label, single-arm, pilot study

ABSTRACT

Gait automaticity is reduced in patients with Parkinson disease (PD) due to impaired habitual control. The aim of this study was to investigate the effect of robot-assisted gait training (RAGT) on gait automaticity as well as gait speed and balance in patients with PD.This study was a prospective, open-label, single-arm, pilot study. We planned to recruit 12 patients with idiopathic PD. Participants received 12 sessions of RAGT using exoskeleton-type robotic device. Sessions were 45-minute each, 3 days a week, for 4 consecutive weeks using an exoskeleton-type gait robot. The primary outcome was the percentage of dual-task interference measured by the 10-Meter Walk Test (10MWT) under single and dual-task (cognitive and physical) conditions. Secondary outcomes were the Berg Balance Scale and Korean version of the Falls Efficacy Scale-International. All measures were evaluated before treatment (T0), after treatment (T1), and 1-month post-treatment (T2).Twelve patients were enrolled and 1 dropped out. Finally, 11 patients with idiopathic PD were analyzed. The mean age of 11 patients (5 males) was 66.46 ± 5.66 years, and disease duration was 112.91 ± 50.19 months. The Hoehn and Yahr stages were 2.5 in 8 patients and 3 in 3 patients. Linear mixed-effect model analysis showed a significant change over time only in single-task gait speed of the 10MWT (P = .007), but not in dual-task gait speed, dual-task interferences, and Korean version of the Falls Efficacy Scale-International. Cognitive dual-task interference significantly increased (P = .026) at T1, but not at T2 (P = .203). No significant changes were observed for physical dual-task interference at T1 and T2. Single-task gait speed of the 10MWT was significantly increased at T1 (P = .041), but not at T2 (P = .445). There were no significant changes in the dual-task gait speed of 10MWT. A significant improvement was observed in Berg Balance Scale score at T1 and T2 (P = .004 and P = .024, respectively).In this pilot study, despite improvement in walking speed and balance, gait automaticity in patients with PD was not improved by RAGT using an exoskeleton-type robot. Additional therapeutic components may be needed to improve gait automaticity using RAGT in patients with PD.

3D visual cueing shortens the double support phase of the gait cycle in patients with advanced Parkinson's disease treated with DBS of the STN

Background

Gait disturbances have emerged as some of the main therapeutic concerns in late-stage Parkinson’s disease (PD) treated with dopaminergic therapy and deep brain stimulation (DBS). External cues may help to overcome freezing of gait (FOG) and improve some of the gait parameters.

Aim

To evaluate the effect of 3D visual cues and STN-DBS on gait in PD group.

Methods

We enrolled 35 PD patients treated with DBS of nucleus subthalamicus (STN-DBS). Twenty-five patients (5 females; mean age 58.9 ±6.3) and 25 sex- and age-matched controls completed the gait examination. The gait in 10 patients deteriorated in OFF state. The severity of PD was evaluated using the Unified Parkinson's Disease Rating Scale (UPDRS) and Hoehn and Yahr (HY). The PD group filled the Falls Efficacy Scale-International (FES) and Freezing of Gait Questionnaire (FOGQ). Gait was examined using the GaitRite Analysis System, placed in the middle of the 10m marked path. The PD group was tested without dopaminergic medication with and without visual cueing together with the DBS switched ON and OFF. The setting of DBS was double-blind and performed in random order.

Results

The UPDRS was 21.9 ±9.5 in DBS ON state and 41.3 ±13.7 in DBS OFF state. HY was 2.5 ±0.6, FES 12.4 ±4.1 and FOGQ 9.4 ±5.7. In the DBS OFF state, PD group walked more slowly with shorter steps, had greater step length variability and longer duration of the double support phase compared to healthy controls. The walking speed and step length increased in the DBS ON state. The double support phase was reduced with 3D visual cueing and DBS; the combination of both cueing and DBS was even more effective.

Conclusion

Cueing with 3D visual stimuli shortens the double support phase in PD patients treated with DBS-STN. The DBS is more effective in prolonging step length and increasing gait speed. We conclude that 3D visual cueing can improve walking in patients with DBS.

Transcutaneous magnetic spinal cord stimulation for freezing of gait in Parkinson's disease

Dopaminergic drugs partially alleviate gait problems in Parkinson's disease, but the effects are not sustained in the long-term. Particularly, the freezing of gait directly impacts patients' quality of life. Experimental epidural spinal cord stimulation (SCS) studies have suggested positive effects on locomotion among PD patients, but the effects of non-invasive stimulation have never been explored. Here, we investigated in a prospective, open-label, pilot study the efficacy and safety of non-invasive magnetic stimulation of the spinal cord in five patients with PD who experienced gait problems, including freezing of gait. A trial of transcutaneous magnetic SCS was performed at the level of the fifth thoracic vertebra. The primary outcome was the change in freezing of gait 7 days after stimulation. Secondary outcome measures included changes in gait speed and UPDRS part III. After non-invasive spinal cord stimulation, patients experienced a 22% improvement in freezing of gait (p = 0.040) and 17.4% improvement in the UPDRS part III (p = 0.042). Timed up and go times improved by 48.2%, although this did not reach statistical significance (p = 0.06). Patients' global impression of change was 'much improved' for four patients. Improvement in gait after stimulation was reversible, since it returned to baseline scores 4 weeks after stimulation. No severe side effects were recorded. This pilot study suggests that transcutaneous magnetic spinal cord stimulation is feasible and can potentially improve gait problems in PD, without severe adverse effects. Large scale phase II trials are needed to test this hypothesis.

Demonstration of Kinematic-Based Closed-loop Deep Brain Stimulation for Mitigating Freezing of Gait in People with Parkinson's Disease

Impaired gait in Parkinson's disease is marked by slow, arrhythmic stepping, and often includes freezing of gait episodes where alternating stepping halts completely. Wearable inertial sensors offer a way to detect these gait changes and novel deep brain stimulation (DBS) systems can respond with clinical therapy in a real-time, closed-loop fashion. In this paper, we present two novel closed-loop DBS algorithms, one using gait arrhythmicity and one using a logistic-regression model of freezing of gait detection as control signals. Benchtop validation results demonstrate the feasibility of running these algorithms in conjunction with a closed-loop DBS system by responding to real-time human subject kinematic data and pre-recorded data from leg-worn inertial sensors from a participant with Parkinson's disease. We also present a novel control policy algorithm that changes neurostimulator frequency in response to the kinematic inputs. These results provide a foundation for further development, iteration, and testing in a clinical trial for the first closed-loop DBS algorithms using kinematic signals to therapeutically improve and understand the pathophysiological mechanisms of gait impairment in Parkinson's disease.

Ankle and Foot Spasticity Patterns in Chronic Stroke Survivors with Abnormal Gait

Chronic stroke survivors with spastic hemiplegia have various clinical presentations of ankle and foot muscle spasticity patterns. They are mechanical consequences of interactions between spasticity and weakness of surrounding muscles during walking. Four common ankle and foot spasticity patterns are described and discussed through sample cases. The patterns discussed are equinus, varus, equinovarus, and striatal toe deformities. Spasticity of the primary muscle(s) for each deformity is identified. However, it is emphasized that clinical presentation depends on the severity of spasticity and weakness of these muscles and their interactions. Careful and thorough clinical assessment of the ankle and foot deformities is needed to determine the primary cause of each deformity. An understanding of common ankle and foot spasticity patterns can help guide clinical assessment and selection of target spastic muscles for botulinum toxin injection or nerve block.

Therapy of Parkinson's Disease Subtypes

Early descriptions of subtypes of Parkinson's disease (PD) are dominated by the approach of predetermined groups. Experts defined, from clinical observation, groups based on clinical or demographic features that appeared to divide PD into clinically distinct subsets. Common bases on which to define subtypes have been motor phenotype (tremor dominant vs akinetic-rigid or postural instability gait disorder types), age, nonmotor dominant symptoms, and genetic forms. Recently, data-driven approaches have been used to define PD subtypes, taking an unbiased statistical approach to the identification of PD subgroups. The vast majority of data-driven subtyping has been done based on clinical features. Biomarker-based subtyping is an emerging but still quite undeveloped field. Not all of the subtyping methods have established therapeutic implications. This may not be surprising given that they were born largely from clinical observations of phenotype and not in observations regarding treatment response or biological hypotheses. The next frontier for subtypes research as it applies to personalized medicine in PD is the development of genotype-specific therapies. Therapies for GBA-PD and LRRK2-PD are already under development. This review discusses each of the major subtyping systems/methods in terms of its applicability to therapy in PD, and the opportunities and challenges designing clinical trials to develop the evidence base for personalized medicine based on subtypes.

Botulinum Toxin Type A Injections Impact Hamstring Muscles and Gait Parameters in Children with Flexed Knee Gait

The aim of this study was to determine if botulinum toxin type A (BoNT-A) injection into the medial hamstring can improve gait kinematics and muscle-tendon length in spastic cerebral palsy (CP) with a flexed knee gait (FKG). Twenty-nine children with spastic CP (Gross Motor Function Classification System I–III) with FKG were recruited for this prospective study. BoNT-A was injected into the semitendinosus and semimembranosus (SM) muscles under ultrasonography guidance. Assessments included Gross Motor Function Measure (GMFM), Modified Ashworth Scale (MAS), Modified Tardieu Scale (MTS), 3-dimensional computerized gait analysis, calculated SM muscle-tendon length and lengthening velocity during gait using musculoskeletal modeling at baseline, 4 and 16 weeks after the injection. Compared to baseline data, significant improvements in GMFM, MAS, and MTS were demonstrated at weeks 4 and 16, and also a significant increase in maximum knee extension during the stance phase was observed at week 4. In addition, the mean lengthening velocity during the swing phase was increased at week 16 without a change in the SM muscle length. Furthermore, there was a significant increase in anterior pelvic tilt at week 4, compared to baseline data. The significant decrease in hip internal rotation after injection was observed only in children with excessive hip internal rotation at initial contact before injection. BoNT-A injection into hamstrings leads to a significant increase in knee extension and anterior pelvic tilt with an increase in lengthening velocity of SM in spastic CP with FKG.

Optimized Design of a Variable Viscosity Link for Robotic AFO

Herein we present the development of a novel Ankle Foot Orthosis for gait support of people with foot-drop symptoms. The developed AFO uses an elastic link mechanism to brake the ankle joint during initial contact, thus mitigating foot-slap, and an integrated energy store-and-release mechanism to support toe lift in the swing phase, thus mitigating toe-drag. This paper presents improvements in the braking-holding power of the elastic link mechanism over its previous version, the torque-angle characteristics of the developed AFO with the renewed elastic link, and a pilot test with one person with foot-drop symptoms to verify the proposed functions of the developed AFO.

Education level affects dual-task gait after deep brain stimulation in Parkinson's disease

INTRODUCTION

High cognitive reserve is associated with milder cognitive and motor deficits in Parkinson's disease (PD). We investigated whether educational status (as a proxy for cognitive reserve) could modulate dual-task (DT) related gait changes after subthalamic nucleus deep brain stimulation (STN-DBS) in PD.

METHODS

DT-related gait changes were assessed in 34 PD patients (age: 60.5 ± 8.7; % female: 44%), before and one year after STN-DBS. Based on walking speed change after DBS, patients were classified into responders (improvement) and non-responders (deterioration) using automated k-means clustering for four DT (i.e. forward and backward counting; semantic and phonemic fluency).

RESULTS

Patients with high education level improved DT gait performance compared to lower educated patients (p = 0.03). Baseline cognitive performance, disease progression and stimulation efficiency were similar between groups (i.e. responders versus non-responders). Logistic regression showed an association between responders and high level of education for verbal fluency (semantic/phonemic fluency, beta = 3.9/3.4, p = 0.03). No significant changes for any gait parameter were found using all-group analyses.

CONCLUSION

Education level is associated with DT-related gait changes in PD one year post-DBS. Subgroup analyses should be considered for highly variable gait outcomes after STN-DBS. With regard to the predominance of motor-cognitive DT performance in everyday life, a high CR could be considered as a favourable inclusion criterion for future DBS candidates.

Effects of rhythmic auditory cueing on stepping in place in patients with Parkinson's disease

BACKGROUND

Stepping in place (SIP) is a useful locomotor training intervention. The purpose of this study was to investigate the effects of single auditory-cued SIP training on cortical excitability, rhythmic movements and walking ability in patients with Parkinson's disease(PD).

METHODS

Cross-over randomized control trial. Each participant completed two interventions with at least one-week washout period in between: (1) SIP with concurrent auditory cues (AC condition) and (2) SIP without auditory cues (NC condition).

RESULTS

In the primary outcome, the cortical silent period (CSP) duration increased (P = .005), whereas short intracortical inhibition (SICI) decreased after training (P = .001). Freezers demonstrated enhanced inhibition in the resting motor threshold and CSP duration. SICI and intracortical facilitation were modulated in both groups under the AC condition. In the secondary outcomes, the stepping variability decreased significantly (AC: P = .033; NC: P = .009), whereas walking cadence increased after training (AC: P = .019; NC: P = .0023).

CONCLUSIONS

Auditory-cued SIP training improved the lower-limb movement variability and modulated the cortical excitability in patients with PD. Freezers may benefit more from this training than nonfreezers.

The Influence of Orthotics on Lower Limbs Biomechanics in CP

The biomechanics of the human body has a direct impact on the quality of gait cycle. Patients with Cerebral Palsy (CP) often present incorrect gait patterns associated with structural deformities which directly influence the locomotor functions. The key to therapeutic success in those patients is the use of lower limb orthotics of the AFO type. This type of orthopedic devices should correct the skeletal deformities, optimize function and ensure high quality of daily use. Alignment of the lower limb supported by orthotics in all planes is crucial for changing the abnormal position of the ground reaction force (GRF) vector during a pathological gait cycle. GRFs produce an external moment of forces that causes extension or flexion of the lower limb in the sagittal plane. At the same time, those external conditions are balanced by an internal moment of forces generated by muscles. Some of the muscles are not directly attached to the joints but still support their function. This mechanism is called biomechanical coupling. This interesting relationship is also related to the inclination or reclination of the shank vertical angle (SVA) against the foot fixed on the ground in the midstance (MST) phase of gait. An optimal SVA angle is 7-12 degrees of tibial inclination. An insufficient or excessive SVA angle can be controlled by ankle foot orthotics (AFO). Those types of splints provide for better control of foot clearance during the swing phase and support distal stability of the lower limb chain during the stance phase of the gait cycle. An interdisciplinary approach is the key to success in the therapy of CP children who use lower limb orthotics. Nowadays, tridimensional gait analysis is an important tool for objective monitoring of those patients. It shows all kinematic and kinetic data recorded during gait with AFO and therefore helps to fine-tune orthotics used by CP patients.

Combined exercise and visual gaze training improves stepping accuracy in people with diabetic peripheral neuropathy

INTRODUCTION

Patients with diabetes and diabetic peripheral neuropathy (DPN) place their feet with less accuracy whilst walking, which may contribute to the increased falls-risk. This study examines the effects of a multi-faceted intervention on stepping accuracy, in patients with diabetes and DPN.

METHODS

Forty participants began the study, of which 29 completed both the pre and post-intervention tests, 8 patients with DPN, 11 patients with diabetes but no neuropathy (D) and 10 healthy controls (C). Accuracy of stepping was measured pre- and post-intervention as participants walked along an irregularly arranged stepping walkway. Participants attended a one-hour session, once a week, for sixteen weeks, involving high-load resistance exercise and visual-motor training.

RESULTS

Patients who took part in the intervention improved stepping accuracy (DPN: +45%; D: +36%) (p < 0.05). The diabetic non-intervention (D-NI) group did not display any significant differences in stepping accuracy pre- to post- the intervention period (-7%).

DISCUSSION

The improved stepping accuracy observed in patients with diabetes and DPN as a result of this novel intervention, may contribute towards reducing falls-risk. This multi-faceted intervention presents promise for improving the general mobility and safety of patients during walking and could be considered for inclusion as part of clinical treatment programmes.

Effect of ankle-foot orthosis on functional mobility and dynamic balance of patients after stroke: Study protocol for a randomized controlled clinical trial

INTRODUCTION

Stroke is the principal cause of impairment in the motor function and gait of adults. One of the resources used in rehabilitation to optimize gait is a prescription of ankle-foot orthosis (AFO), and the most prescribed AFOs are Fixed AFO and Articulated AFO; however, it is not known which of these options is more effective for these individuals. The aim of this study is to evaluate the impact of different types of ankle-foot orthosis functional mobility and dynamic balance in stroke patients.

METHODS

Prospective randomized controlled clinical trial with 2 parallel groups will be conducted, and the aim is to recruit 50 patients with stroke diagnosis within 1 year, who indicated that they use both types of orthotics, who had a previous Rankin score less than or equal to 3, and who obtained AFO orthosis through the Hospital Clinics at the Botucatu Medical School (HCBMS) São Paulo, Brazil. After a specific evaluation by a physiotherapist, the patient will receive 1 of the AFO types via randomization. After 30 days, the patient will be reevaluated. The primary outcomes will be balance and mobility, which will be evaluated by the Time Up Go Test (TUG) and Tinetti's Scale of Mobility and Balance (TSMB). The secondary outcomes will be quality of life and the levels of anxiety and depression, which will be evaluated with the European (5D) Quality of Life Scale (Euroqol) and Hospital Anxiety and Depression Scale (HADS). Group allocation will be not concealed because the blinding of participants and of therapists that provide intervention is not possible, and all analyses will be based on an intention-to-treat principle. This study was approved by the Human Research Ethics Committee of the São Paulo State University UNESP, number 2.367.953. The results will be published in relevant journal.

DISCUSSION

The results of this study will contribute to clinical practice by identifying the type of AFO orthosis that is more suitable for this condition, helping to standardize prescription of these orthoses by professionals, and guiding future research studies on this subject, which is still incompletely defined in the literature.

TRIAL REGISTRATION

RBR-6SF2VV (March 5, 2018).

Enhancing GABAergic Transmission Improves Locomotion in a Caenorhabditis elegans Model of Spinal Muscular Atrophy

Spinal muscular atrophy (SMA) is a neuromuscular disease characterized by degeneration of spinal motor neurons resulting in variable degrees of muscular wasting and weakness. It is caused by a loss-of-function mutation in the survival motor neuron (SMN1) gene. Caenorhabditis elegans mutants lacking SMN recapitulate several aspects of the disease including impaired movement and shorted life span. We examined whether genes previously implicated in life span extension conferred benefits to C. elegans lacking SMN. We find that reducing daf-2/insulin receptor signaling activity promotes survival and improves locomotor behavior in this C. elegans model of SMA. The locomotor dysfunction in C. elegans lacking SMN correlated with structural and functional abnormalities in GABAergic neuromuscular junctions (NMJs). Moreover, we demonstrated that reduction in daf-2 signaling reversed these abnormalities. Remarkably, enhancing GABAergic neurotransmission alone was able to correct the locomotor dysfunction. Our work indicated that an imbalance of excitatory/inhibitory activity within motor circuits and underlies motor system dysfunction in this SMA model. Interventions aimed at restoring the balance of excitatory/inhibitory activity in motor circuits could be of benefit to individuals with SMA.

The effects of anodal tDCS over the supplementary motor area on gait initiation in Parkinson's disease with freezing of gait: a pilot study

OBJECTIVE

We investigated if anodal transcranial direct current stimulation (A-tDCS), applied over the supplementary motor areas (SMAs), could improve gait initiation in Parkinson's disease (PD) with freezing of gait (FOG).

METHODS

In this double-blinded cross-over pilot study, ten PD with FOG underwent two stimulation sessions: A-tDCS (1 mA, 10 min) and sham stimulation. Eight blocks of gait initiation were collected per session: (1) pre-tDCS, with acoustic cueing; (2) pre-tDCS, self-initiated (no cue); and (3-8) post-tDCS, self-initiated. Gait initiation kinetics were analyzed with two-way repeated measures ANOVAs for the effects of A-tDCS.

RESULTS

A-tDCS did not significantly improve the magnitude or timing of anticipatory postural adjustments or the execution of the first step during self-initiated gait compared with baseline measures (p > .13). The lack of significant change was not due to an inability to generate functional APAs since external cueing markedly improved gait initiation (p < .01).

CONCLUSIONS

A single dose of A-tDCS over the SMAs did not improve self-initiated gait in PD and FOG. Alternative approaches using a different dose or cortical target are worthy of exploration since individuals demonstrated the capacity to improve.

SIGNIFICANCE

Neuromodulation strategies tailored to facilitate SMA activity may be ineffective for the treatment of gait initiation impairment in people with PD and FOG.

Effects of Electromechanical Exoskeleton-Assisted Gait Training on Walking Ability of Stroke Patients: A Randomized Controlled Trial

OBJECTIVE

To assess the efficacy of electromechanical exoskeleton-assisted gait training on walking ability of stroke patients based on ambulatory function, muscle strength, balance, gait speed, and capacity.

DESIGN

Randomized controlled trial.

SETTING

University rehabilitation hospital.

PARTICIPANTS

Individuals (N=40) with stroke who could stand alone.

INTERVENTIONS

Patients were randomly assigned to control and experimental groups. The control group underwent physical therapist-assisted gait training by conventional method. The experimental group underwent electromechanical gait training assisted by an exoskeleton device. Both types of gait training were performed for 30 minutes each day. The therapeutic interventions were provided for 5 days a week for a period of 4 weeks in both groups.

MAIN OUTCOME MEASURES

Functional ambulatory category (FAC) before and after gait training. Changes in FAC were the primary outcomes to evaluate the efficacy of electromechanical exoskeleton-assisted gait training. Changes in mobility, walking speed, walking capacity, leg muscle strength, daily activity, and balance were secondary outcomes.

RESULTS

FAC in the control group was 2.44±1.55 in the pretraining and 2.75±1.53 in the post-training. FAC in the experimental group was 3.22±1.31 in the pretraining and 3.78±1.44 in the post-training. Although FAC between pre- and post-training sessions improved in both groups, the changes in FAC were statistically significant in the experimental group alone. Most secondary outcomes in both groups also showed improvement after gait training. However, the differential outcomes were not varied between the 2 groups after adjusting the data for age and stroke duration. We did not exclude patients based on time since stroke onset. The average stroke duration was 530.11±389.21 days in the experimental group. The changes in FAC of the experimental group were negatively correlated with stroke duration. No adverse events were noticed during gait training in either group.

CONCLUSIONS

Electromechanical exoskeleton-assisted gait training is as effective as conventional gait training by a physical therapist when administered by a gait trainer. As an overground walking system without harness, electromechanical exoskeleton replaced a physical therapist in assisted gait training for patients who stand alone. Because the ambulatory function of stroke patients was affected negatively by stroke duration, the effect of electromechanical-assisted gait training might decline with increased stroke duration.