Effects of ankle-foot orthoses on gait parameters in post-stroke patients with different Brunnstrom stages of the lower limb: a single-center crossover trial.

BACKGROUND: Ankle-foot orthoses (AFO) can improve gait posture and walking ability in post-stroke patients. However, the effect of AFO on gait parameters in post-stroke patients according to the Brunnstrom stage of stroke recovery of the lower limbs remains unclear. The study aimed to investigate whether stroke patients with different Brunnstrom stages benefit from wearing AFO. METHODS: Twenty-five post-stroke participants included 18 men (50 ± 13 years) and 7 women (60 ± 15 years). The patients were divided based on Brunnstrom stage III or IV of the lower limbs. All patients underwent the gait and timed up and go (TUG) test using a gait analysis system while walking barefoot or with an AFO. The spatiotemporal and asymmetric parameters were analyzed. RESULTS: All 25 patients completed the study. Significant differences were observed between barefoot and AFO use in TUG time (P < 0.001) but not walking velocity (P > 0.05). The main effect of the swing time ratio was significant in both groups (P < 0.05); however, the main effects of stride length, stance time, and gait asymmetry ratio were nonsignificant (P > 0.05). For barefoot versus AFO, the main effects of stride length (P < 0.05) and swing time (P < 0.01) ratios were significant, whereas those of stance time and gait asymmetry ratio were nonsignificant (P > 0.05). CONCLUSIONS: Post-stroke patients with lower Brunnstrom stages benefitted more from AFO, particularly in gait asymmetry.

Gait training with a safety suspension device accelerates the achievement of supervision level walking in subacute stroke: a randomized controlled trial.

Practicing walking in a safety suspension device allows patients to move freely and without excessive reliance on a therapist, which requires correcting errors and may facilitate motor learning. This opens the possibility that patients with subacute stroke may improve their walking ability more rapidly. Therefore, we tested the hypothesis that overground gait training in a safety suspension device will result in achieving faster supervision-level walking than gait training without the suspension device. Twenty-seven patients with stroke admitted to the rehabilitation ward with functional ambulation categories (FAC) score of 2 at admission were randomly allocated to safety suspension-device group (SS group) or conventional assisted-gait training group (control group). In addition to regular physical therapy, each group underwent additional gait training for 60 min a day, 5 days a week for 4 weeks. We counted the days until reaching a FAC score of 3 and assessed the probability using Cox regression models. The median days required to reach a FAC score of 3 were 7 days for the SS group and 17.5 days for the control group, which was significantly different between the groups ( P  < 0.05). The SS group had a higher probability of reaching a FAC score of 3 after adjusting for age and admission motor impairment (hazard ratio = 3.61, 95% confidence interval = 1.40-9.33, P  < 0.01). The gait training with a safety suspension device accelerates reaching the supervision-level walking during inpatient rehabilitation. We speculate that a safety suspension device facilitated learning by allowing errors to be experienced and correct in a safe environment.

The effects of plantarflexor weakness and reduced tendon stiffness with aging on gait stability.

Falls among older adults are a costly public health concern. Such falls can be precipitated by balance disturbances, after which a recovery strategy requiring rapid, high force outputs is necessary. Sarcopenia among older adults likely diminishes their ability to produce the forces necessary to arrest gait instability. Age-related changes to tendon stiffness may also delay muscle stretch and afferent feedback and decrease force transmission, worsening fall outcomes. However, the association between muscle strength, tendon stiffness, and gait instability is not well established. Given the ankle's proximity to the onset of many walking balance disturbances, we examined the relation between both plantarflexor strength and Achilles tendon stiffness with walking-related instability during perturbed gait in older and younger adults-the latter quantified herein using margins of stability and whole-body angular momentum including the application of treadmill-induced slip perturbations. Older and younger adults did not differ in plantarflexor strength, but Achilles tendon stiffness was lower in older adults. Among older adults, plantarflexor weakness associated with greater whole-body angular momentum following treadmill-induced slip perturbations. Weaker older adults also appeared to walk and recover from treadmill-induced slip perturbations with more caution. This study highlights the role of plantarflexor strength and Achilles tendon stiffness in regulating lateral gait stability in older adults, which may be targets for training protocols seeking to minimize fall risk and injury severity.

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.

Human-centered design of a novel soft exosuit for post-stroke gait rehabilitation.

BACKGROUND: Stroke remains a major cause of long-term adult disability in the United States, necessitating the need for effective rehabilitation strategies for post-stroke gait impairments. Despite advancements in post-stroke care, existing rehabilitation often falls short, prompting the development of devices like robots and exoskeletons. However, these technologies often lack crucial input from end-users, such as clinicians, patients, and caregivers, hindering their clinical utility. Employing a human-centered design approach can enhance the design process and address user-specific needs. OBJECTIVE: To establish a proof-of-concept of the human-centered design approach by refining the NewGait® exosuit device for post-stroke gait rehabilitation. METHODS: Using iterative design sprints, the research focused on understanding the perspectives of clinicians, stroke survivors, and caregivers. Two design sprints were conducted, including empathy interviews at the beginning of the design sprint to integrate end-users' insights. After each design sprint, the NewGait device underwent refinements based on emerging issues and recommendations. The final prototype underwent mechanical testing for durability, biomechanical simulation testing for clinical feasibility, and a system usability evaluation, where the new stroke-specific NewGait device was compared with the original NewGait device and a commercial product, Theratogs®. RESULTS: Affinity mapping from the design sprints identified crucial categories for stakeholder adoption, including fit for females, ease of donning and doffing, and usability during barefoot walking. To address these issues, a system redesign was implemented within weeks, incorporating features like a loop-backed neoprene, a novel closure mechanism for the shoulder harness, and a hook-and-loop design for the waist belt. Additional improvements included reconstructing anchors with rigid hook materials and replacing latex elastic bands with non-latex silicone-based bands for enhanced durability. Further, changes to the dorsiflexion anchor were made to allow for barefoot walking. Mechanical testing revealed a remarkable 10-fold increase in durability, enduring 500,000 cycles without notable degradation. Biomechanical simulation established the modularity of the NewGait device and indicated that it could be configured to assist or resist different muscles during walking. Usability testing indicated superior performance of the stroke-specific NewGait device, scoring 84.3 on the system usability scale compared to 62.7 for the original NewGait device and 46.9 for Theratogs. CONCLUSION: This study successfully establishes the proof-of-concept for a human-centered design approach using design sprints to rapidly develop a stroke-specific gait rehabilitation system. Future research should focus on evaluating the clinical efficacy and effectiveness of the NewGait device for post-stroke rehabilitation.

Principal Component Analysis Enhanced with Bootstrapped Confidence Interval for the Classification of Parkinsonian Patients Using Gaussian Mixture Model and Gait Initiation Parameters.

Parkinson's disease is one of the major neurodegenerative diseases that affects the postural stability of patients, especially during gait initiation. There is actually an increasing demand for the development of new non-pharmacological tools that can easily classify healthy/affected patients as well as the degree of evolution of the disease. The experimental characterization of gait initiation (GI) is usually done through the simultaneous acquisition of about 20 variables, resulting in very large datasets. Dimension reduction tools are therefore suitable, considering the complexity of the physiological processes involved. The principal Component Analysis (PCA) is very powerful at reducing the dimensionality of large datasets and emphasizing correlations between variables. In this paper, the Principal Component Analysis (PCA) was enhanced with bootstrapping and applied to the study of the GI to identify the 3 majors sets of variables influencing the postural control disability of Parkinsonian patients during GI. We show that the combination of these methods can lead to a significant improvement in the unsupervised classification of healthy/affected patients using a Gaussian mixture model, since it leads to a reduced confidence interval on the estimated parameters. The benefits of this method for the identification and study of the efficiency of potential treatments is not addressed in this paper but could be addressed in future works.

Analysis of gait characteristics and related factors in patients with Parkinson's disease based on wearable devices.

BACKGROUND: Postural instability and gait disorder dominant (PIGD) is one of the most common disabling symptoms of Parkinson's disease (PD), which seriously affects patients' quality of life. Therefore, it is essential to identify PIGD and develop targeted interventions to reduce the risk of PIGD in PD patients. AIM: This study aimed to investigate the gait characteristics of PD patients based on wearable devices and to establish a predictive model for their related influencing factors. METHODS: The retrospective medical records of patients from January 2020 to September 2023 were collected, including 159 patients with PD (divided into PIGD [n = 73] and non-PIGD [n = 86] groups) and 200 healthy patients (as the healthy control group). Information from social demographic data, a blood test, scale scores, gait analysis based on wearable devices, white matter lesions, and the Fazekas scale was extracted and analyzed. RESULTS: Compared with the healthy control group, the mean step length, mean rate, mean angular velocity, and step length were lower in the PD group, while the mean steps were higher in the turning test. The incidence of PIGD was 46% in PD patients, and PD patients with the non-tremor onset mode were more likely to develop PIGD than those with the tremor onset mode. Compared to the non-PIGD group, the PIGD group showed more serious gait problems in different experimental tasks and had a higher Hoehn and Yahr (H-Y) stage, Hamilton Anxiety Scale (HAMA) score, Hamilton Depression Scale score, periventricular white matter (PVWM) score, deep white matter score, and Fazekas scale score, but they had lower hemoglobin levels, D-dimer levels, Tinetti Balance scores, Tinetti Gait scores, Berg Balance Scale scores, and Mini-Mental State Examination (MMSE) scores. Logistic regression analysis showed that the MMSE score was negatively correlated with the occurrence of PIGD, while the HAMA score, H-Y stage, PVWM score, and non-tremor form of onset were positively correlated with the occurrence of PIGD CONCLUSION: The incidence of gait disorder in PD patients is higher than that in the normal population. Moreover, cognitive dysfunction, anxiety state, H-Y stage, PVWM score, and the non-tremor mode of onset can be considered independent risk factors for PIGD.

Application of sensory nerve quantitative tests to analyze the subtypes of motor disorders in Parkinson's disease.

This study investigated the sensory nerve function in people with different subtypes of Parkinson's disease (PD), which included the tremor-dominant (TD) group (n = 30), postural instability and gait disorder (PIGD) group (n = 33), and healthy-controls (HC) group (n = 33). Sural nerve's current perception threshold (CPT) and pain tolerance threshold (PTT) in both feet were measured at different frequencies. Results were evaluated using the mini-mental state examination (MMSE), Hoehn Yahr scale (H-Y) , and 3-meter timed-up-and-go-test (TUGT). The MMSE scores of the TD and HC groups were higher than those of the PIGD group (TD < HC). The 3-meter TUGT scores of the PIGD group were higher than theTD and HC groups (TD > HC). The PIGD patients experienced a significantly shorter disease duration and higher H-Y score than the TD patients ( P  < 0.05). The values of 2 KHz CPT of left-side (CPTL), 2KHz CPT of right-side (CPTR), and 5 Hz CPTR in the PIGD group were significantly higher compared to the TD and HC groups ( P  < 0.05, Bonferroni correction). Additionally, the values of 250 Hz CPTL, 5 Hz CPTL, 250 Hz CPTR, 2 kHz PTT of left-side (PTTL), 250 Hz PTTL, and 5 Hz PTTL in the PIGD group were significantly elevated relative to the TD group ( P  < 0.05, Bonferroni correction). Distinctive current threshold perception and PTT of the sural nerve can be observed in patients with varying PD subtypes, and sensory nerve conduction threshold electrical diagnostic testing can detect these discrepancies in sensory nerve function.

Reorganization of structural brain networks in Parkinson's disease with postural instability/gait difficulty.

The Postural Instability/Gait Difficulty (PIGD) subtype of Parkinson's disease (PD) has a faster disease progression, a higher risk of cognitive and motor decline, yet the alterations of structural topological organization remain unknown. Diffusion Tensor Imaging (DTI) and 3D-TI scanning were conducted on 31 PD patients with PIGD (PD-PIGD), 30 PD patients without PIGD (PD-non-PIGD) and 35 Healthy Controls (HCs). Structural networks were constructed using DTI brain white matter fiber tractography. A graph theory approach was applied to characterize the topological properties of complex structural networks, and the relationships between significantly different network metrics and motor deficits were analyzed within the PD-PIGD group. PD-PIGD patients exhibited increased shortest path length compared with PD-non-PIGD and HCs (P < 0.05, respectively). Additionally, PD-PIGD patients exhibited decreased nodal properties, mainly in the cerebellar vermis, prefrontal cortex, paracentral lobule, and visual regions. Notably, the degree centrality of the cerebellar vermis was negatively correlated with the PIGD score (r = -0.390; P = 0.030) and Unified Parkinson's Disease Rating Scale Part III score (r = -0.436; P = 0.014) in PD-PIGD patients. Furthermore, network-based statistical analysis revealed decreased structural connectivity between the prefrontal lobe, putamen, supplementary motor area, insula, and cingulate gyrus in PD-PIGD patients. Our findings demonstrated that PD-PIGD patients existed abnormal structural connectomes in the cerebellar vermis, frontal-parietal cortex and visual regions. These topological differences can provide a topological perspective for understanding the potential pathophysiological mechanisms of PIGD in PD.

Effects of a 12-week telehealth exercise intervention on gait speed and gait deviations in adults with Down syndrome.

BACKGROUND: Altered gait patterns and reduced walking speed are commonly reported in adults with Down syndrome (DS). Research on the effects of DS-specific exercise programmes on adults with DS is lacking. The purpose of this quasi-experimental study was to evaluate the changes in gait deviations and walking speed in adults with DS after a DS-specific exercise programme. METHODS: Twenty participants underwent a 12-week, DS-specific exercise programme in a telehealth format. Before and after the intervention, gait deviations were assessed with the Ranchos Los Amigos Observational Gait Analysis form, and comfortable walking speed was evaluated with the 4-m walk test. RESULTS: We observed increased comfortable walking speed and reduced gait deviations in the whole gait cycle in adults with DS after the intervention. There were fewer gait deviations during single-leg stance and swing-limb advancement and at the hip, knee and ankle joints after the 12-week exercise programme. CONCLUSIONS: Gait speed and observable gait impairments in adults with DS significantly improved following a 12-week telehealth exercise programme.

Freezing of gait in idiopathic normal pressure hydrocephalus.

BACKGROUND: Reports of freezing of gait (FoG) in idiopathic normal pressure hydrocephalus (iNPH) are few and results are variable. This study's objective was to evaluate the frequency of FoG in a large cohort of iNPH patients, identify FoG-associated factors, and assess FoG's responsiveness to shunt surgery. METHODS: Videotaped standardized gait protocols with iNPH patients pre- and post-shunt surgery (n = 139; median age 75 (71-79) years; 48 women) were evaluated for FoG episodes by two observers (Cohens kappa = 0.9, p < 0.001). FoG episodes were categorized. Mini-mental state examination (MMSE) and MRI white matter hyperintensities (WMH) assessment using the Fazekas scale were performed. CSF was analyzed for Beta-amyloid, Tau, and Phospho-tau. Patients with and without FoG were compared. RESULTS: Twenty-two patients (16%) displayed FoG at baseline, decreasing to seven (8%) after CSF shunt surgery (p = 0.039). The symptom was most frequently exhibited during turning (n = 16, 73%). Patients displaying FoG were older (77.5 vs. 74.6 years; p = 0.029), had a slower walking speed (0.59 vs. 0.89 m/s; p < 0.001), a lower Tinetti POMA score (6.8 vs. 10.8; p < 0.001), lower MMSE score (21.3 vs. 24.0; p = 0.031), and longer disease duration (4.2 vs. 2.3 years; p < 0.001) compared to patients not displaying FoG. WMH or CSF biomarkers did not differ between the groups. CONCLUSIONS: FoG is occurring frequently in iNPH patients and may be considered a typical feature of iNPH. FoG in iNPH was associated with higher age, longer disease duration, worse cognitive function, and a more unstable gait. Shunt surgery seems to improve the symptom.

Enfermedad de Huntington de inicio en la infancia. Una presentación poco frecuente / Childhood-onset Huntignton´s disease. A rare presentation

Introducción La enfermedad de Huntington (EH) es una enfermedad de herencia autosómica dominante caracterizada por la expansión de tripletes de citosina-adenina-guanina (CAG) en el gen que codifica la huntingtina. Los síntomas en la descendencia suelen ser más tempranos por el fenómeno de anticipación. La clínica de inicio en la infancia, antes de los 10 años, difiere de la observada en la adultez. Se manifiesta por afectación motora, dificultades conductuales y retraso o regresión del desarrollo. La corea es infrecuente. El objetivo del caso es describir aspectos clínicos de una paciente con EH de inicio infantil. Caso clínico Niña de 5 años con antecedentes familiares de EH y desarrollo típico hasta los 3 años. Presentó progresivamente afectación del lenguaje con habilidades descendidas para su edad en aspectos expresivos y comprensivos, sin afectación en las habilidades pragmáticas y sociales. En cuanto a la motricidad, la marcha y la bipedestación eran inestables, y mostraba rigidez, distonía y movimientos coreicos. Presentó atrofia de los núcleos lenticulares y caudados en la resonancia magnética, y posteriormente se realizó el diagnóstico molecular con la expansión de tripletes CAG (51 copias). Conclusión La EH de inicio en la infancia presenta manifestaciones clínicas distintas a la forma del adulto. Debe considerarse en pacientes con afectación motora y cognitiva progresiva. Por la herencia familiar, es importante interrogar cuidadosamente sobre los antecedentes familiares y tenerla en cuenta aun sin familiares afectados por el fenómeno de anticipación. (AU)

INTRODUCTIO NHuntington’s disease (HD) is a rare autosomal dominant disease caused by the expansion of CAG triplets in the gene that encodes huntingtin. There are earlier symptoms’ onset in offspring due to the phenomenon of anticipation. The clinical features of childhood-onset HD, before age 10 years, differs from adult-onset form. It is characterized by motor impairment, behavioral difficulties and delay or regression in areas of development; while chorea is rarely seen. In this case we describe clinical aspects of a patient with childhood-onset Huntington’s disease. CASE REPORT A 5-year-old girl with a family history of HD and typical development up to 3 years of age. She progressively acquired language impairment with skills that were below her age in expressive and receptive areas, without deficits in pragmatic and social skills. Regarding motor skills, she manifested instability at walking and standing, with rigidity, dystonia and choreic movements. Atrophy of the basal ganglia was evident on MRI, EEG was normal, and molecular confirmation of CAG triplet revealed repeat length of 51 copies. CONCLUSION. Childhood-onset HD differs from adult-form´s clinical manifestations. It should be considered in patients with progressive motor and cognitive impairment. Due to family inheritance, it is important to carefully examine family history and take it into account even without relatives affected, considering the anticipation phenomenon. (AU)

Towards a better understanding of anticipatory postural adjustments in people with Parkinson's disease.

INTRODUCTION: Previous studies have shown that anticipatory postural adjustments (APAs) are altered in people with Parkinson's disease but its meaning for locomotion is less understood. This study aims to investigate the association between APAs and gait initiation, gait and freezing of gait and how a dynamic postural control challenging training may induce changes in these features. METHODS: Gait initiation was quantified using wearable sensors and subsequent straight walking was assessed via marker-based motion capture. Additionally, turning and FOG-related outcomes were measured with wearable sensors. Assessments were conducted one week before (Pre), one week after (Post) and 4 weeks after (Follow-up) completion of a training intervention (split-belt treadmill training or regular treadmill training), under single task and dual task (DT) conditions. Statistical analysis included a linear mixed model for training effects and correlation analysis between APAs and the other outcomes for Pre and Post-Pre delta. RESULTS: 52 participants with Parkinson's disease (22 freezers) were assessed. We found that APA size in the medio-lateral direction during DT was positively associated with gait speed (p<0.001) and stride length (p<0.001) under DT conditions at Pre. The training effect was largest for first step range of motion and was similar for both training modes. For the associations between changes after the training (pooled sample) medio-lateral APA size showed a significant positive correlation with first step range of motion (p = 0.033) only in the DT condition and for the non-freezers only. CONCLUSIONS: The findings of this work revealed new insights into how APAs were not associated with first step characteristics and freezing and only baseline APAs during DT were related with DT gait characteristics. Training-induced changes in the size of APAs were related to training benefits in the first step ROM only in non-freezers. Based on the presented results increasing APA size through interventions might not be the ideal target for overall improvement of locomotion.

Use of a Robotic Walking Device for Home and Community Mobility in Parkinson Disease: A Randomized Controlled Trial.

BACKGROUND/PURPOSE: Gait impairments in Parkinson disease (PD) contribute to decreased quality of life. This randomized controlled trial examined immediate- and longer-term effects of a single joint robotic exoskeleton device (EXOD), the Honda Walking Assist device, on gait. METHODS: Participants (n = 45) with PD (Hoehn and Yahr stages 1-3) were randomized to a robotic-assisted gait training (RAGT) group (n = 23) or control (CON) group (n = 22). The RAGT group was tested with and without the EXOD at baseline and then received supervised in-home and community training with the EXOD twice weekly for 8 weeks. The CON group received no interventions. Outcome measures included gait speed (primary), gait endurance (6-minute walk test), perceived ease of walking, and questionnaires and logs assessing performance of daily activities, freezing of gait, and daily activity levels. RESULTS: Forty participants completed the study. No significant immediate impact of EXOD usage on participants' gait measures was found. Differences in gait speed and secondary outcome measures postintervention were not significantly different between the RAGT and CON groups. Participants with greater disease severity (worse baseline motor scores) had greater improvements in stride length during unassisted walking after the intervention than those with lower severity (mean difference: 3.22, 95% confidence interval: 0.05-6.40; P = 0.04). DISCUSSION AND CONCLUSIONS: All RAGT participants could use the EXOD safely. The RAGT treatment used in this mostly low impairment population of people with PD may be ineffective and/or was insufficiently dosed to see a positive treatment effect. Our findings suggest that RAGT interventions in PD may be more effective in individuals with greater motor impairments.

Journey to 1 Million Steps: A Retrospective Case Series Analyzing the Implementation of Robotic-Assisted Gait Training Into an Outpatient Pediatric Clinic.

PURPOSE: To describe the implementation of an exoskeleton program in a rehabilitation setting using a Design Thinking framework. METHODS: This is a retrospective case series of 3 randomly selected children who participated in skilled physical therapy using a pediatric exoskeleton that occurred on our journey to walking 1 000 000 steps in the exoskeleton devices. Participants ranged in age from 3 to 5 years, and all had neurologic disorders. RESULTS: All participants improved toward achieving their therapy goals, tolerated the exoskeleton well, and had an increased number of steps taken over time. CONCLUSION: The implementation of new technology into pediatric care and an established outpatient therapy clinic is described. The Design Thinking process applies to health care professionals and improves clinical care. Exoskeletons are effective tools for use in pediatric physical therapy.

Freezing of gait assessment with inertial measurement units and deep learning: effect of tasks, medication states, and stops.

BACKGROUND: Freezing of gait (FOG) is an episodic and highly disabling symptom of Parkinson's Disease (PD). Traditionally, FOG assessment relies on time-consuming visual inspection of camera footage. Therefore, previous studies have proposed portable and automated solutions to annotate FOG. However, automated FOG assessment is challenging due to gait variability caused by medication effects and varying FOG-provoking tasks. Moreover, whether automated approaches can differentiate FOG from typical everyday movements, such as volitional stops, remains to be determined. To address these questions, we evaluated an automated FOG assessment model with deep learning (DL) based on inertial measurement units (IMUs). We assessed its performance trained on all standardized FOG-provoking tasks and medication states, as well as on specific tasks and medication states. Furthermore, we examined the effect of adding stopping periods on FOG detection performance. METHODS: Twelve PD patients with self-reported FOG (mean age 69.33 ± 6.02 years) completed a FOG-provoking protocol, including timed-up-and-go and 360-degree turning-in-place tasks in On/Off dopaminergic medication states with/without volitional stopping. IMUs were attached to the pelvis and both sides of the tibia and talus. A temporal convolutional network (TCN) was used to detect FOG episodes. FOG severity was quantified by the percentage of time frozen (%TF) and the number of freezing episodes (#FOG). The agreement between the model-generated outcomes and the gold standard experts' video annotation was assessed by the intra-class correlation coefficient (ICC). RESULTS: For FOG assessment in trials without stopping, the agreement of our model was strong (ICC (%TF) = 0.92 [0.68, 0.98]; ICC(#FOG) = 0.95 [0.72, 0.99]). Models trained on a specific FOG-provoking task could not generalize to unseen tasks, while models trained on a specific medication state could generalize to unseen states. For assessment in trials with stopping, the agreement of our model was moderately strong (ICC (%TF) = 0.95 [0.73, 0.99]; ICC (#FOG) = 0.79 [0.46, 0.94]), but only when stopping was included in the training data. CONCLUSION: A TCN trained on IMU signals allows valid FOG assessment in trials with/without stops containing different medication states and FOG-provoking tasks. These results are encouraging and enable future work investigating automated FOG assessment during everyday life.

Effects of transcranial direct current stimulation alone and in combination with rehabilitation therapies on gait and balance among individuals with Parkinson's disease: a systematic review and meta-analysis.

BACKGROUND: Parkinson's disease (PD) is a neurogenerative disorder implicated in dysfunctions of motor functions, particularly gait and balance. Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation offered as a potential adjuvant therapy for PD. This systematic review and meta-analysis were conducted to identify whether tDCS alone and combined with additional rehabilitation therapies improve gait and balance among individuals with PD. METHODS: We searched PubMed, Embase, Web of Science, and relevant databases for eligible studies from inception to December 2022. Studies with a comparative design investigating the effects of tDCS on motor functions, including gait and balance among individuals with PD, were included. A meta-analysis was performed for each outcome using a random effects model for subgroup analysis and pooling of overall effect sizes. RESULTS: A total of 23 studies were included in the meta-analysis. The pooled results revealed that tDCS has moderate overall effects on gait, measured by gait speed (standardized mean deviation [SMD] = 0.238; 95% confidence interval [CI] - 0.026 to 0.502); stride length (SMD = 0.318; 95% CI - 0.015 to 0.652); cadence (SMD = - 0.632; 95% CI - 0.932 to - 0.333); freezing of gait questionnaire scores (SMD = - 0.360; 95% CI - 0.692 to - 0.027); step length (SMD = 0.459; 95% CI - 0.031 to 0.949); walking time (SMD = - 0.253; 95% CI - 0.758 to 0.252); stride time (SMD = - 0.785; 95% CI: - 1.680 to 0.111); double support time (SMD = 1.139; 95% CI - 0.244 to 0.523); and balance, measured by timed up and go (TUG) test (SMD = - 0.294; 95% CI - 0.516 to - 0.073), Berg balance scale (BBS) scores (SMD = 0.406; 95% CI - 0.059 to 0.87), and dynamic gait index (SMD = 0.275; 95% CI - 0.349 to 0.898). For the subgroup analysis, gait and balance demonstrated moderate effect sizes. However, only cadence, stride time, and TUG indicated a significant difference between real and sham tDCS (P = 0.027, P = 0.002, and P = 0.023, respectively), whereas cadence and BBS (P < 0.01 and P = 0.045, respectively) significantly differed after real tDCS plus other therapies rather than after sham tDCS plus other therapies. CONCLUSIONS: Our results indicated that tDCS is significantly associated with gait and balance improvements among individuals with PD. The findings of this study provide more proof supporting the effectiveness of tDCS, encouraging tDCS to be utilized alone or in combination with other therapies in clinical practice for PD rehabilitation.

Patterns of regional cerebral hypoperfusion in early Parkinson's disease: Clinical implications.

INTRODUCTION: This study aimed to investigate whether regional cerebral perfusion patterns on early-phase 18F-FP-CIT PET scans, which is typically coupled to cerebral metabolism, predict the long-term prognosis of Parkinson's disease (PD). METHODS: We enrolled 397 drug-naïve patients with early-stage PD who underwent dual-phase 18F-FP-CIT PET scans. After quantifying the early-phase 18F-FP-CIT PET images, cluster analysis was performed to delineate the PD subtypes according to the patterns of regional cerebral perfusion. We compared the risk of developing levodopa-induced dyskinesia (LID), wearing-off, freezing of gait (FOG), and dementia between the PD subtypes. RESULTS: Cluster analysis classified patients into three subtypes: cluster 1 (relatively preserved cortical uptake; n = 175), cluster 2 (decreased uptake in the frontal, parietal, and temporal regions; n = 151), and cluster 3 (decreased uptake in more extensive regions, additionally involving the lateral occipital regions; n = 71). Cluster 1 was characterized by a younger age-of-onset, less severe motor deficits, less severely decreased 18F-FP-CIT binding in the caudate, and better cognitive performance. Cluster 3 was characterized by an older age-of-onset, more severe motor deficits, and poorer cognitive performance. Cluster 2 was intermediate between clusters 1 and 3. Cox regression analyses demonstrated that clusters 2 and 3 had a higher risk for dementia conversion than cluster 1, whereas the risk for developing LID, wearing-off, and FOG did not differ among the clusters. CONCLUSION: The patterns of regional cerebral perfusion can provide information on long-term prognosis with regards to cognitive, but not motor aspects of patients with early-stage PD.

Patterns and assessment of spastic hemiplegic gait.

Hemiparetic gait disorders are common in stroke survivors. A circumductory gait is often considered the typical hemiparetic gait. In clinical practice, a wide spectrum of abnormal gait patterns is observed, depending on the severity of weakness and spasticity, and the anatomical distribution of spasticity. Muscle strength is the key determinant of gait disorders in hemiparetic stroke survivors. Spasticity and its associated involuntary activation of synergistic spastic muscles often alter posture of involved joint(s) and subsequently the alignment of hip, knee, and ankle joints, resulting in abnormal gait patterns. Due to combinations of various levels of muscle weakness and spasticity and their interactions with ground reaction force, presentations of gait disorders are variable. From a neuromechanical perspective, a stepwise visual gait analysis approach is proposed to identify primary underlying causes. In this approach, the pelvic and hip joint movement is examined first. The pelvic girdle constitutes three kinematic determinants. Its abnormality determines the body vector and compensatory kinetic chain reactions in the knee and ankle joints. The second step is to assess the ankle and foot complex abnormality. The last step is to examine abnormality of the knee joint. Assessment of muscle strength and spasticity of hip, knee, and ankle/foot joints needs to be performed before these steps. Lidocaine nerve blocks can be a useful diagnostic tool. Recognizing different patterns and identifying the primary causes are critical to developing clinical interventions to improve gait functions.