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Abstract This reference dataset contains biomechanical data of 138 able-bodied adults (21–86 years) and 50 stroke survivors walking bare-footed at their preferred speed. It is unique due to its size, and population, including adults across the life-span and over 70 years, as well as stroke survivors. Full-body kinematics (PiG-model), kinetics and muscle activity of 14 back and lower limbs muscles was collected with a Vicon motion capture system, ground-embedded force plates, and a synchronized surface EMG system. The data is reliable to compare within and between groups as the same methodology and infrastructure were used to gather all data. Both source files (C3D) and post-processed ready-to-use stride-normalized kinematics, kinetics and EMG data (MAT-file, Excel file) are available, allowing high flexibility and accessibility of analysis for both researchers and clinicians. These records are valuable to examine ageing, typical and hemiplegic gait, while also offering a wide range of reference data which can be utilized for age-matched controls during normal walking.

BackgroundLower limb motor recovery, including abnormal muscle synergies, occurs mainly within the first 5–8 weeks after a stroke. This suggests the importance of delivering impairment-focused therapies, such as therapeutic robots that promote symmetric gait, during this time-sensitive period, following the principle of “the earlier, the better.”ObjectiveFirst, to compare early robotic training (ERT) with usual care (UC) against UC alone on restoring intralimb muscle synergies and interlimb symmetry during functional tasks; Second, to investigate whether ERT is superior to delayed robotic training (DRT) starting after the proposed time-sensitive period.MethodsThis observer-blinded, randomized pilot trial with crossover design involved 19 nonambulatory adults included within 14 days poststroke. Those allocated to ERT (N = 10) received immediately 4 weeks of training (16 sessions, 4× /week) with the Ekso GT® above UC and were compared with the DRT group (N = 9) who received UC alone at this point. Thereafter a 3-week UC period followed to investigate sustainability of ERT and the interventional roles were exchanged; at about week 8 poststroke DRT subjects started the same experimental robotic protocol and ERT subjects continued UC as controls. Outcomes included changes in Fugl-Meyer lower extremity scores (FM-LE) reflecting muscle synergies, weight-bearing asymmetry (WBA), and dynamic control asymmetry (DCA) during quiet standing. Functional ambulation category (FAC) was used to classify walking independence (cut-off ≥4).ResultsA trend toward earlier reacquisition of walking independence favoring ERT with UC over UC was not accompanied by differences in FM-LE, WBA, or DCA (first objective). Thereafter, DRT with UC did not yield any significant changes relative to UC, such that no between-group differences were found favoring restorative effects of ERT over DRT (second objective).ConclusionThis pilot trial shows the feasibility of investigating a wearable exoskeleton as an adjunct therapy in subacute stroke. Nevertheless, our preliminary findings suggest that motor recovery of lower limb muscle synergies was not enhanced by 4 weeks of robotic training to reduce compensations with the less-affected side, irrespective of the timing of application.Trial registrationClinicalTrials.gov, identifier: NCT03727919.

ObjectiveTo systematically evaluate the full spectrum of self-reported chronic symptoms in patients with unilateral vestibular hypofunction (UVH) and to investigate the effect of interventions on these symptoms.MethodsA systematic review was conducted following the guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analysis Statement (PRISMA). A literature search was performed in Pubmed, Web of Science, Embase, and Scopus to investigate self-reported symptoms and self-report questionnaires in patients with UVH. All original studies ranging from full-text clinical trials to case reports, written in English, German, and French, were included. The frequency of self-reported symptoms was presented. For self-report questionnaires, a meta-analysis was carried out to synthesize scale means by the pre- and post-intervention means and mean changes for studies that investigated interventions.ResultsA total of 2,110 studies were retrieved. Forty-seven studies were included after title-abstract selection and full-text selection by two independent reviewers. The symptoms of UVH patients included chronic dizziness (98%), imbalance (81%), symptoms worsened by head movements (75%), visually induced dizziness (61%), symptoms worsened in darkness (51%), and oscillopsia (22%). Additionally, UVH could be accompanied by recurrent vertigo (77%), tiredness (68%), cognitive symptoms (58%), and autonomic symptoms (46%). Regarding self-report questionnaires, UVH resulted on average in a moderate handicap, with an estimated mean total score on the Dizziness Handicap Inventory (DHI) and the Vertigo Symptom Scale (VSS) of 46.31 (95% CI: 41.17–51.44) and 15.50 (95% CI: 12.59–18.41), respectively. In studies that investigated the effect of vestibular intervention, a significant decrease in the estimated mean total DHI scores from 51.79 (95% CI: 46.61–56.97) (pre-intervention) to 27.39 (95% CI: 23.16–31.62) (post intervention) was found (p

Background and Purpose: In individuals with unilateral vestibulopathy (UVP), physical activity (PA) is recommended to stimulate central vestibular compensation. However, the presence of fear avoidance beliefs might negatively influence PA. The objectives of this study were to investigate the relationship between fear avoidance beliefs and PA and to compare PA levels between individuals with UVP in an acute/subacute vs chronic phase. Methods: In this cross-sectional study, PA was measured using a triaxial accelerometer. Fear avoidance beliefs were quantified using the Vestibular Activities Avoidance Instrument. The correlation between fear avoidance beliefs and PA was evaluated using regression analyses, with other potential influencing factors also considered. Results: A total of 102 participants were included. The average age was 56.1 (SD 15.2) years, and 57.8% were male. Participants with chronic UVP presented with shorter sedentary time (4,591 vs 5129 min/wk; P = 0.004), longer standing time (1443 vs 1165 min/wk; P = 0.025), higher vigorous PA (187 vs 107 min/wk; P = 0.005), and higher total PA (773 vs 623 min/wk; P = 0.003) compared to participants with acute/subacute UVP. In participants with acute/subacute UVP, variability in total PA was explained up to 54.7% by fear avoidance beliefs, etiology of the UVP, and gender (R 2 = 0.547, F 4,45 = 13.6, P < 0.001). In participants with chronic UVP, fear avoidance beliefs explained 4.1% of the variability in total PA (R 2 = 0.041, F 1,49 = 2.086, P = 0.155). Discussion and Conclusions: In acute/subacute UVP, assessing fear avoidance beliefs helps to understand physical inactivity. In chronic UVP, no significant association between fear avoidance beliefs and PA was observed. for more insights from the authors (see the video, Supplemental Digital Content, available at: http://links.lww.com/JNPT/A488). [ABSTRACT FROM AUTHOR]

Objective: Chronic dizziness after acute unilateral vestibulopathy (AUVP) causes significant social and economic burdens. This study aims to identify predictors of chronic dizziness. Study Design: Prospective, longitudinal cohort study. Setting: ENT departments from secondary and tertiary hospitals. Methods: Participants meeting the Barany Society's diagnostic criteria for AUVP were included. Evaluations occurred within 0 to 21 days (T1), and at 4 (T2) and 10 weeks (T3) postonset. The primary outcome measure was the Dizziness Handicap Inventory (DHI) at 6 months, with a score >30 indicating chronic dizziness. Five clusters of predictors were assessed at T1‐3: central vestibular compensation, visual dependence, movement exposure, psychological factors, and balance performance. Separate linear regression models for T1, T2, and T3 were constructed to explain the variability in the 6‐month DHI score. Receiver operating characteristics analyses were conducted to predict chronic dizziness. Results: From June 2021 to January 2024, 103 participants (55.2 ± 16.6 years old, 49 women) were included. The regression models explained the variability in the 6‐month DHI score by 33.0% at T1, 47.6% at T2, and 64.0% at T3 (P <.001), including psychological factors (T1, T2, T3), visual dependence (T2, T3), and static balance performance (T3). Cutoff values for the Vestibular Activities Avoidance Instrument (23/54), Visual Vertigo Analog Scale (33.5/100), and Hospital Anxiety and Depression Scale‐Anxiety (7.5/21) at 10 weeks postonset predicted chronic dizziness. Conclusion: Higher psychological burden, increased visual dependence, and poorer static balance performance were associated with chronic dizziness. Cutoff values were determined to identify individuals with AUVP at risk for chronic dizziness. [ABSTRACT FROM AUTHOR]

The characterization of the molecular composition of organic carbon in both gaseous and aerosol is key to understanding the processes involved in the formation and aging of secondary organic aerosol. Therefore a technique using active sampling on cartridges and filters and derivatization followed by analysis using a thermal desorption–gas chromatography–mass spectrometer (TD–GC–MS) has been used. It is aimed at studying the molecular composition of organic carbon in both gaseous and aerosol phases (PM2.5) during an intensive field campaign which took place in Corsica (France) during the summer of 2013: the ChArMEx (Chemistry and Aerosol Mediterranean Experiment) SOP1b (Special Observation Period 1B) campaign. These measurements led to the identification of 51 oxygenated (carbonyl and or hydroxyl) compounds in the gaseous phase with concentrations between 21 and 3900 ng m−3 and of 85 compounds in the particulate phase with concentrations between 0.3 and 277 ng m−3. Comparisons of these measurements with collocated data using other techniques have been conducted, showing fair agreement in general for most species except for glyoxal in the gas phase and malonic, tartaric, malic and succinic acids in the particle phase, with disagreements that can reach up to a factor of 8 and 20 on average, respectively, for the latter two acids. Comparison between the sum of all compounds identified by TD–GC–MS in the particle phase and the total organic matter (OM) mass reveals that on average 18 % of the total OM mass can be explained by the compounds measured by TD–GC–MS. This number increases to 24 % of the total water-soluble OM (WSOM) measured by coupling the Particle Into Liquid Sampler (PILS)-TOC (total organic carbon) if we consider only the sum of the soluble compounds measured by TD–GC–MS. This highlights the important fraction of the OM mass identified by these measurements but also the relative important fraction of OM mass remaining unidentified during the campaign and therefore the complexity of characterizing exhaustively the organic aerosol (OA) molecular chemical composition. The fraction of OM measured by TD–GC–MS is largely dominated by di-carboxylic acids, which represent 49 % of the PM2.5 content detected and quantified by this technique. Other contributions to PM2.5 composition measured by TD–GC–MS are then represented by tri-carboxylic acids (15 %), alcohols (13 %), aldehydes (10 %), di-hydroxy-carboxylic acids (5 %), monocarboxylic acids and ketones (3 % each), and hydroxyl-carboxylic acids (2 %). These results highlight the importance of polyfunctionalized carboxylic acids for OM, while the chemical processes responsible for their formation in both phases remain uncertain. While not measured by the TD–GC–MS technique, humic-like substances (HULISs) represent the most abundant identified species in the aerosol, contributing for 59 % of the total OM mass on average during the campaign. A total of 14 compounds were detected and quantified in both phases, allowing the calculation of experimental partitioning coefficients for these species. The comparison of these experimental partitioning coefficients with theoretical ones, estimated by three different models, reveals large discrepancies varying from 2 to 7 orders of magnitude. These results suggest that the supposed instantaneous equilibrium being established between gaseous and particulate phases assuming a homogeneous non-viscous particle phase is questionable.

IntroductionA vestibular schwannoma (VS) resection causes an acute unilateral vestibular deafferentation resulting in acute postoperative symptoms. Despite the expected resolution of most of the symptoms, due to central vestibular compensation, more than one out of four patients develop chronic dizziness. Several predictive factors, such as age and tumor size, have been suggested. Despite its potential effect on the process of central vestibular compensation, the level of physical activity after VS resection was not yet considered. Therefore, the association between the level of physical activity and chronic dizziness after VS resection will be investigated.MethodsThis retrospective cohort study included 66 patients who underwent a retro-sigmoid VS resection between October 2001 and February 2007. Patients were assessed before surgery and at 9 weeks and 6 months postoperatively. At 9 weeks, patients were asked to report their level of physical activity (PA) during the past week by using a visual analogue scale and their balance performance was assessed by four standing balance conditions with eyes closed and the Timed Up and Go test (TUG). Based on the Dizziness Handicap Inventory (DHI) score at 6 months, patients were divided in a chronic dizziness group (DHI > 30) and non-chronic dizziness group (DHI-score ≤ 30). Age, sex, Koos classification, preoperative vestibular function, treatment group, balance performance, and level of PA were compared between both groups and used as independent variables in linear regression analyses with the DHI score at 6 months as dependent variable.ResultsThe chronic dizzy patients revealed to have significantly lower levels of PA (p < 0.001) and worse static and dynamic balance performance (p = 0.023 and p = 0.041, respectively) 9 weeks after surgery. After elimination, the multiple regression analysis resulted in a model with two variables (PA level, TUG) which significantly predicted the DHI score (F2,42 = 6.581; R2 = 0.239; p = 0.003).ConclusionThis study revealed associations between (1) the level of PA and balance performance in the subacute phase and (2) chronic dizziness after VS resection. Assessment of the level of PA and balance performance during the subacute phase, which can be performed in a non-invasive and non-time-consuming way, might therefore provide prognostic information after VS resection.

Abstract Integration of accurate vestibular, visual, and proprioceptive information is crucial in managing the centre of mass in relation to the base of support during gait. Therefore, bilateral loss of peripheral vestibular function can be highly debilitating when performing activities of daily life. To further investigate the influence of an impaired peripheral vestibular system on gait stability, spatiotemporal parameters, step-to-step variability, and mechanical stability parameters were examined in 20 patients with bilateral vestibulopathy and 20 matched healthy controls during preferred overground walking. Additionally, using a partial least squares analysis the relationship between spatiotemporal parameters of gait and the margins of stability was explored in both groups. Patients with bilateral vestibulopathy showed an increased cadence compared to healthy controls (121 ± 9 vs 115 ± 8 steps/min; p = 0.02; d = 0.77). In addition, although not significant (p = 0.07), a moderate effect size (d = 0.60) was found for step width variability (Coefficient of Variation (%); Bilateral vestibulopathy: 19 ± 11%; Healthy controls: 13 ± 5%). Results of the partial least squares analysis suggest that patients with peripheral vestibular failure implement a different balance control strategy. Instead of altering the step parameters, as is the case in healthy controls, they use the single and double support phases to control the state of the centre of mass to improve the mechanical stability.

Introduction Balance deficits are heterogeneous among children with Developmental Coordination Disorder (DCD). Balance performance depends on different balance domains, each associated with specific underlying neurological systems. In DCD, any of these domains can be affected, but the control mechanisms are poorly understood. The mirror neuron system (MNS) seems to play a key-role in DCD-related deficits. To understand the role of MNS as a control mechanism underlying the balance deficits, simultaneous registration of cortical MNS activity while performing balance tasks is imperative. Therefore, a protocol for combining real-time registration of cortical MNS activity during functional balance tasks in children with DCD, CP and TD is introduced. Methods: Children with DCD, CP and TD (n=108) aged 5-10yr perform preselected tasks of the Kids-BESTest, representing specific balance domains (mixed design): leaning with eyes closed (stability limits/verticality), single-leg-stance, alternate stair touching (anticipatory balance), in-place response, compensatory stepping backward (reactive balance) and walking over obstacles (gait stability). Simultaneously, functional Near-Infrared Spectroscopy (fNIRS) monitors cortical activity involving the MNS: premotor, inferior and superior parietal cortex and supplementary motor area. An 8-8-optode bundle, making 22 channels, targets this region of interest. Outcome measures are: (de)oxygenated hemoglobin concentration changes per task per channel. Results: In this ongoing research, the protocol was already feasible in 19 children (7.52±1.19). Conclusion: Simultaneous registration of cortical MNS activity (fNIRS) and Kids-BESTest scores will help increase the understanding of the control mechanisms underlying the heterogeneous balance problems in DCD. Consequently, first steps are made to confirm whether DCD shows deviant or delayed development. Disclosure No significant relationships.

Electrochemical impedance spectroscopy (EIS) is a versatile technique to characterize electrochemical systems satisfying causality, linearity and stationarity requirements. Odd Random Phase multisine EIS (ORP-EIS) can measure time-varying impedances for non-stationary processes. In this work, operando ORP-EIS is introduced to monitor the anodizing of aluminum, which is a nonlinear and non-stationary process, by superimposing a multisine AC perturbation signal on the anodizing DC potential. Results show that the multisine signal does not disturb the growth of the oxide film. Moreover, this technique makes it possible to follow the growth of the barrier oxide layer and provides an opportunity to investigate processes like ion adsorption, ion incorporation and ion movements through the oxide layer during anodizing. These processes cannot be studied by conventional EIS.