Current practices in clinical gait analysis in Europe: A comprehensive survey-based study from the European society for movement analysis in adults and children (ESMAC) standard initiative.

BACKGROUND: Clinical gait analysis (CGA) is a systematic approach to comprehensively evaluate gait patterns, quantify impairments, plan targeted interventions, and evaluate the impact of interventions. However, international standards for CGA are currently lacking, resulting in various national initiatives. Standards are important to ensure safe and effective healthcare practices and to enable evidence-based clinical decision-making, facilitating interoperability, and reimbursement under national healthcare policies. Collaborative clinical and research work between European countries would benefit from common standards. RESEARCH OBJECTIVE: This study aimed to review the current laboratory practices for CGA in Europe. METHODS: A comprehensive survey was conducted by the European Society for Movement Analysis in Adults and Children (ESMAC), in close collaboration with the European national societies. The survey involved 97 gait laboratories across 16 countries. The survey assessed several aspects related to CGA, including equipment used, data collection, processing, and reporting methods. RESULTS: There was a consensus between laboratories concerning the data collected during CGA. The Conventional Gait Model (CGM) was the most used biomechanical model for calculating kinematics and kinetics. Respondents also reported the use of video recording, 3D motion capture systems, force plates, and surface electromyography. While there was a consensus on the reporting of CGA data, variations were reported in training, documentation, data preprocessing and equipment maintenance practices. SIGNIFICANCE: The findings of this study will serve as a foundation for the development of standardized guidelines for CGA in Europe.

Upper limb motor dysfunction is associated with fragmented kinetics after brain injury.

BACKGROUND: Characterization of motor deficits after brain injury is important for rehabilitation personalization. While studies reported abnormalities in the kinematics of paretic and non-paretic elbow extension for patients with brain injuries, kinematic analysis is not sufficient to explore how patients deal with musculoskeletal redundancy and the energetic aspect of movement execution. Conversely, interarticular coordination and movement kinetics can reflect patients' motor strategies. This study investigates motor strategies of paretic and non-paretic upper limb after brain injury to highlight motor deficits or compensation strategies. METHODS: 26 brain-injured hemiplegic patients and 24 healthy controls performed active elbow extensions in the horizontal plane, with both upper limbs for patients and, with the dominant upper limb for controls. Elbow and shoulder kinematics, interarticular coordination, net joint kinetics were quantified. FINDINGS: Results show alterations in kinematics, and a strong correlation between elbow and shoulder angles, as well as time to reach elbow and shoulder peak angular velocity in both upper limbs of patients. Net joint kinetics were lower for paretic limb and highlighted a fragmented motor strategy with increased number of transitions between concentric and eccentric phases. INTERPRETATION: In complement to kinematic results, our kinetic results confirmed patients' difficulties to manage both spatially and temporally the joint degrees of freedom redundancy but revealed a fragmented compensatory motor strategy allowing patients upper limb extension despite quality alteration and decrease in energy efficiency. Motor rehabilitation should improve the management of this fragmentation strategy to improve the performance and the efficiency of active movement after brain injury.

ToulGaitViz: a tool for the systematic description of lower limb clearance during the swing phase of hemiparetic gait after stroke. A cohort study.

BACKGROUND: In post-stroke hemiparetic subjects, a systematic and quantified description of the shortening default and compensatory movements during the swing phase of gait is essential to guide treatments and assess the impact of therapeutic interventions. However, such a systematic approach does not exist in the current clinical practice. AIM: The aim of this study was to present a method improving the quantification and visualization of the kinematics of both lower limbs during the swing phase of gait, more specifically the origin of shortening default and the weight of compensations, based on a tool specifically developed: ToulGaitViz. DESIGN: Observational cohort study. SETTING: Three-dimensional kinematic gait analyses of outpatients evaluated in Toulouse university hospital. POPULATION: ToulGaitViz was applied to 151 post-stroke hemiparetic participants and 48 healthy control participants. METHODS: ToulGaitViz is a standalone software allowing to compute 1) limb clearance as the sum of the shortening related to hip, knee and ankle flexion in the sagittal plane; 2) compensations related to the abduction of the limb and hip hiking at mid-swing. Both centimetric and angular values of the clearance were reported as well as their correlations with walking speed. RESULTS: Overall, the contribution of compensations in clearance was higher in post-stroke hemiparetic subjects than in healthy control participants with both centimetric (130% vs. 33%; P<0.001) and angular methods (23% vs. 1.4%; P<0.001). The centimetric method better represents the specific contribution of each segment to the clearance than the angular method. Symbolically, mean kinematic data from the cohort supports the claim that 2° of pelvic obliquity is equivalent to 10° of knee flexion to increase clearance by 1 cm, emphasizing the non-proportionality between the angular values and the actual contribution to the shortening. ToulGaitViz allows visualization of clearance, segmental shortening and compensation evolution before and after any therapeutic intervention with quantitative and comprehensive data. CONCLUSIONS: The ToulGaitViz could be systematically used in clinical practice to extract relevant kinematic data from the origin of shortening default and the weight of compensations. CLINICAL REHABILITATION IMPACT: This tool allows better understanding of the mechanisms of action of treatments to better link them to the subjects' needs.

Assessing Spatiotemporal and Quality Alterations in Paretic Upper Limb Movements after Stroke in Routine Care: Proposal and Validation of a Protocol Using IMUs versus MoCap.

Accurate assessment of upper-limb movement alterations is a key component of post-stroke follow-up. Motion capture (MoCap) is the gold standard for assessment even in clinical conditions, but it requires a laboratory setting with a relatively complex implementation. Alternatively, inertial measurement units (IMUs) are the subject of growing interest, but their accuracy remains to be challenged. This study aims to assess the minimal detectable change (MDC) between spatiotemporal and quality variables obtained from these IMUs and MoCap, based on a specific protocol of IMU calibration and measurement and on data processing using the dead reckoning method. We also studied the influence of each data processing step on the level of between-system MDC. Fifteen post-stroke hemiparetic subjects performed reach or grasp tasks. The MDC for the movement time, index of curvature, smoothness (studied through the number of submovements), and trunk contribution was equal to 10.83%, 3.62%, 39.62%, and 25.11%, respectively. All calibration and data processing steps played a significant role in increasing the agreement. The between-system MDC values were found to be lower or comparable to the between-session MDC values obtained with MoCap, meaning that our results provide strong evidence that using IMUs with the proposed calibration and processing steps can successfully and accurately assess upper-limb movement alterations after stroke in clinical routine care conditions.

Corticomuscular and intermuscular coherence are correlated after stroke: a simplified motor control?

During movement, corticomuscular coherence is a measure of central-peripheral communication, while intermuscular coherence is a measure of the amount of common central drive to the muscles. Although these two measures are modified in stroke subjects, no author has explored a correlation between them, neither in stroke subjects nor in healthy subjects. Twenty-four chronic stroke subjects and 22 healthy control subjects were included in this cohort study, and they performed 20 active elbow extension movements. The electroencephalographic and electromyographic activity of the elbow flexors and extensors were recorded. Corticomuscular and intermuscular coherence were calculated in the time-frequency domain for each limb of stroke and control subjects. Partial rank correlations were performed to study the link between these two variables. Our results showed a positive correlation between corticomuscular and intermuscular coherence only for stroke subjects, for their paretic and non-paretic limbs (P < 0.022; Rho > 0.50). These results suggest, beyond the cortical and spinal hypotheses to explain them, that stroke subjects present a form of simplification of motor control. When central-peripheral communication increases, it is less modulated and more common to the muscles involved in the active movement. This motor control simplification suggests a new way of understanding the plasticity of the neuromuscular system after stroke.

Comparison between a novel helical and a posterior ankle-foot orthosis on gait in people with unilateral foot drop: a randomised crossover trial.

BACKGROUND: Neuromuscular disease and peripheral neuropathy may cause drop foot with or without evertor weakness. We developed a helical-shaped, non-articulated ankle-foot orthosis (AFO) to provide medial-lateral stability while allowing mobility, to improve gait capacity. Our aim was to evaluate the effect of the helical AFO (hAFO) on functional gait capacity (6-min walk test) in people with peripheral neuropathy or neuromuscular disease (NMD) causing unilateral drop foot and compare with a posterior leaf spring AFO (plsAFO). Secondary aims were to compare functional mobility, 3D kinematic and kinetic gait variables and satisfaction between the AFOs. METHODS: Single centre, randomised crossover trial from January to July 2017 in 20 individuals (14 with peripheral neuropathy and 6 with NMD, 12 females, mean age 55.6 years, SD 15.3); 10 wore the hAFO for the first week and 10 wore the plsAFO before switching for the second week. The 6-min walk test (6MWT), Timed Up and Go (TUG) test and 3D gait analysis were evaluated with the hAFO, the plsAFO and shoes only (noAFO) at inclusion and 1 week after wearing each orthosis. Satisfaction was evaluated with the Quebec user evaluation of satisfaction with assistive technology (QUEST). RESULTS: Median [interquartile range] 6MWT distance was greater with the hAFO (444 m [79]) than the plsAFO (389 m [135], P < 0.001, Hedge's g = 0.6) and noAFO (337 m [91], P < 0.001, g = 0.88). TUG time was shorter with the hAFO (8.1 s [2.8]) than the plsAFO (9.5 s [2.6], P < 0.001, g = - 0.5) and noAFO (10.0 s [2.6]), P < 0.001, g = - 0.6). The plsAFO limited plantarflexion during the loading response (plsAFO - 7.5 deg [6.0] vs. noAFO -13.0 deg [10.0], P = 0.0007, g = - 1.0) but the hAFO did not (- 11.0 deg [5.1] vs. noAFO, P = 0.05, g = - 0.5). Quasi-stiffness was lower for the hAFO than plsAFO (P = 0.009, g = - 0.7). The dimensionless eversion moment was higher (though not significantly) with the hAFO than noAFO. Neither orthosis reduced ankle power (P = 0.34). Median total QUEST score was higher for the hAFO (4.7 [0.7]) than the plsAFO (3.6 [0.8]) (P < 0.001, g = 1.9). CONCLUSIONS: The helical orthosis significantly and considerably improved functional gait performance, did not limit ankle mobility, increased lateral stability, though not significantly, and was associated with greater patient satisfaction than the posterior leaf spring orthosis. Trial registration The trial began before registration was mandatory.

Selection criteria for surgical correction of equinovarus foot in adults with brain damage: A systematic scoping review.

OBJECTIVE: To report on preoperative outcomes that guide the choice of surgical techniques to correct equinovarus foot in adults with brain injury. METHODS: Four databases (PubMed, MEDLINE, Cochrane, PEDro) were searched according to the PRISMA guidelines. Studies were included regardless of their level of proof, with no limitation on date of publication, and their quality was assessed with the Methodological Index for Non-Randomized Studies score. RESULTS: We analysed 61 studies (n = 2,293 participants); 523 participants underwent neurotomy, 437 calf musculotendinous lengthening, and 888 tibialis anterior transfer or alternative anterior transfers with the flexor digitorum/hallucis longus (n = 249), the extensor hallucis longus (n = 102), the tibialis posterior (n = 41) and the peroneus longus (n = 41). Two studies were dedicated to osteoarticular surgeries (n = 12 participants). Ankle dorsiflexors motricity was assessed before 70% of neurotomies as compared with 29% before isolated calf lengthening studies, their strength being at least 3/5 in 33% and 50% of the studies concerned, respectively. Passive ankle dorsiflexion was assessed before surgery in 87% of neurotomy studies, with 62% of studies investigating non-retracted spastic equinovarus foot. Before anterior tendon transfer with the tibialis anterior or another muscle, passive ankle dorsiflexion was reported in only 20% and 46% of studies, respectively, and dynamic tibialis anterior activation during gait in 46% and 56%. Although voluntary recruitment of the tibialis anterior produced a better functional result, the presence/correction of varus justified its transfer in 60% of studies as compared with 30% in other transfers, which were justified by hyperactivity or voluntary recruitment of transferred muscle. CONCLUSIONS: This review highlights the poor level of preoperative assessment and the absence of formal criteria to indicate the different surgical approaches in the management of equinovarus foot. It reinforces the interest of a systematic standardized preoperative assessment such as selective motor block and dynamic electromyography to choose the most suitable surgical procedure.

Task and ecologically based assessment of upper-limb passive function before and after botulinum injections in adults with stroke using the Upper-Limb Performance Assessment: French cross-cultural adaptation and feasibility pilot study.

PURPOSE: To test feasibility of a French translation and cross-cultural adaptation of the Upper-Limb Performance Assessment (ULPA) for task and ecologically based assessment of individualized passive function of upper-limb (UL) performance in adults treated with botulinum toxin-A. MATERIALS AND METHODS: A case series with seven adults with stroke (29-74 years) for spastic hypertonia management with passive use objectives (hygiene or positioning) established through Goal Attainment Scaling (GAS). Scores on ULPA Task Performance Mastery (TPM) were obtained through clinical and home-based performances before and after treatment. RESULTS: Time administration per task ranged from 5-10 min. Median (range) ULPA, Task Performance Mastery (ULPA-TPM) scores pre-intervention of 58 mastery (35-71) improved to 75 (58-88). Tau-U demonstrated significant large effect sizes (≥.65) for five participants. Complementary measures demonstrated improvement of passive performance for five participants and improvements in GAS for six participants. Testing indicates excellent intra-rater (ICC = 0.90) and moderate inter-rater (ICC = 0.64) reliability, with SDC of 10.16 and 18.23%, respectively. CONCLUSIONS: French use of ULPA is a promising standardized, objective and ecologically based assessment of passive performance in adults with stroke. Preliminary findings after TCCA support feasibility for measurement of individualized goals for UL passive use. Future studies may explore other tasks and environments. Implications for rehabilitationULPA is a performance-based, criterion-referenced and ecological measure of individualized goals based on task-analysis of upper-limb (UL) performance in real-life situations providing an interest for individualized assessment of activity and participation.The measure provides a standardized and quantitative approach, applicable to passive use of UL across environments, promoting ecological validity of assessment.Preliminary data will support clinical interpretation of change before and after botulinum injections of UL passive performance.Access to a transculturally validated French version of ULPA complements standardized assessment of UL impairment, perceived performance and goal attainment.

AbobotulinumtoxinA Doses in Upper and Lower Limb Spasticity: A Systematic Literature Review.

Disabling limb spasticity can result from stroke, traumatic brain injury or other disorders causing upper motor neuron lesions such as multiple sclerosis. Clinical studies have shown that abobotulinumtoxinA (AboBoNT-A) therapy reduces upper and lower limb spasticity in adults. However, physicians may administer potentially inadequate doses, given the lack of consensus on adjusting dose according to muscle volume, the wide dose ranges in the summary of product characteristics or cited in the published literature, and/or the high quantity of toxin available for injection. Against this background, a systematic literature review based on searches of MEDLINE and Embase (via Ovid SP) and three relevant conferences (2018 to 2020) was conducted in November 2020 to examine AboBoNT-A doses given to adults for upper or lower limb muscles affected by spasticity of any etiology in clinical and real-world evidence studies. From the 1781 unique records identified from the electronic databases and conference proceedings screened, 49 unique studies represented across 56 publications (53 full-text articles, 3 conference abstracts) were eligible for inclusion. Evidence from these studies suggested that AboBoNT-A dose given per muscle in clinical practice varies considerably, with only a slight trend toward a relationship between dose and muscle volume. Expert-based consensus is needed to inform recommendations for standardizing AboBoNT-A treatment initiation doses based on muscle volume.

Changes in intermuscular connectivity during active elbow extension reveal a functional simplification of motor control after stroke.

Background: Stroke alters muscle co-activation and notably leads to exaggerated antagonist co-contraction responsible for impaired motor function. However, the mechanisms underlying this exaggerated antagonist co-contraction remain unclear. To fill this gap, the analysis of oscillatory synchronicity in electromyographic signals from synergistic muscles, also called intermuscular coherence, was a relevant tool. Objective: This study compares functional intermuscular connectivity between muscle pairs of the paretic and non-paretic upper limbs of stroke subjects and the dominant limb of control subjects, concomitantly between two muscle pairs with a different functional role, through an intermuscular coherence analysis. Methods: Twenty-four chronic stroke subjects and twenty-four healthy control subjects were included. Subjects performed twenty elbow extensions while kinematic data and electromyographic activity of both flexor and extensor elbow muscles were recorded. Intermuscular coherence was analyzed in the beta frequency band compared to the assessment of antagonist co-contraction. Results: Intermuscular coherence was higher in the stroke subjects' paretic limbs compared to control subjects. For stroke subjects, the intermuscular coherence of the antagonist-antagonist muscle pair (biceps brachii-brachioradialis) was higher than that of the agonist-antagonist muscle pair (triceps brachii-brachioradialis). For the paretic limb, intermuscular coherence of the antagonist-antagonist muscle pair presented a negative relationship with antagonist co-contraction. Conclusion: Differences in intermuscular coherence between the paretic limbs of stroke subjects and control subjects suggest a higher common central drive during movement. Furthermore, results highlight the association between stroke-related alteration of intermuscular functional connectivity and the alteration of motor function.

Respective Contributions of Instrumented 3D Gait Analysis Data and Tibial Motor Nerve Block on Presurgical Spastic Equinus Foot Assessment: A Retrospective Study of 40 Adults.

Spastic equinus foot is a common deformity in neurologic patients who compromise walking ability. It is related to the imbalance between weak dorsiflexion and overactive plantar flexor muscles. To achieve the best functional results after surgical management, the challenge is to identify the relevant components involved in the deformity using several methods, namely, examination in the supine position, motor nerve blocks allowing transient anesthesia of suspected overactive muscles, and kinematic and electromyographic data collected during an instrumented 3D gait analysis. The procedure is not standardized; its use varies from one team to another. Access to gait analysis laboratories is limited, and some teams do not perform motor nerve blocks. When both examinations are available, instrumental data from the instrumented 3D gait analysis can be used to specify muscle targets for motor blocks, but data collected from both examinations are sometimes considered redundant. This retrospective cohort analysis compared examination in the supine position, temporary motor nerve blocks, and instrumented 3D gait analysis data in 40 adults after brain or spinal cord injuries. Clinical data collected before motor nerve block was not associated with instrumental data to assess calf muscle's overactivity and tibialis anterior function. Improvement of ankle dorsiflexion in the swing phase after tibial motor nerve block was associated with soleus spastic co-contraction during this phase corroborating its involvement in ankle dorsiflexion defects. This study showed the relevance of tibial motor nerve block to remove spastic calf dystonia and facilitate the assessment of calf contracture. It also underlined the need for complementary and specific analyses of the tibialis anterior abnormal activation pattern after motor nerve block to confirm or deny their pathological nature.

Botulinum toxin combined with rehabilitation decrease corticomuscular coherence in stroke patients.

OBJECTIVE: Stroke results in limitation of active range of motion involving antagonist co-contraction. The analysis of brain-muscle connectivity can be used to deepen understanding of motor control alterations associated with the loss of motor function after stroke. This preliminary study aims to investigate the combined effects of botulinum toxin and rehabilitation on corticomuscular coherence to better understand the altered functional reorganization of the central-peripheral network. METHODS: Kinematic, electromyographic and electroencephalographic data were recorded during twenty active elbow extensions in eleven chronic stroke patients and nine healthy control subjects. Active range of motion, antagonist co-contraction and corticomuscular coherence were calculated. RESULTS: The initial increase in corticomuscular coherence in stroke patients was significantly reduced five weeks after the first botulinum toxin injection and twenty weeks away from the third injection, in both agonist and antagonist muscles, with moderate to large effect sizes, concomitantly with a decrease in antagonist co-contraction and an improvement in the active range of motion. CONCLUSIONS: This study highlights for the first time an effect of botulinum toxin injections combined with rehabilitation on corticomuscular coherence in stroke patients. SIGNIFICANCE: Notwithstanding the relatively small sample, the results provide original evidence supporting treatment-induced effective functional reorganization of the central-peripheral network.

Modeling the acceptability of BCIs for motor rehabilitation after stroke: A large scale study on the general public.

Introduction: Strokes leave around 40% of survivors dependent in their activities of daily living, notably due to severe motor disabilities. Brain-computer interfaces (BCIs) have been shown to be efficiency for improving motor recovery after stroke, but this efficiency is still far from the level required to achieve the clinical breakthrough expected by both clinicians and patients. While technical levers of improvement have been identified (e.g., sensors and signal processing), fully optimized BCIs are pointless if patients and clinicians cannot or do not want to use them. We hypothesize that improving BCI acceptability will reduce patients' anxiety levels, while increasing their motivation and engagement in the procedure, thereby favoring learning, ultimately, and motor recovery. In other terms, acceptability could be used as a lever to improve BCI efficiency. Yet, studies on BCI based on acceptability/acceptance literature are missing. Thus, our goal was to model BCI acceptability in the context of motor rehabilitation after stroke, and to identify its determinants. Methods: The main outcomes of this paper are the following: i) we designed the first model of acceptability of BCIs for motor rehabilitation after stroke, ii) we created a questionnaire to assess acceptability based on that model and distributed it on a sample representative of the general public in France (N = 753, this high response rate strengthens the reliability of our results), iii) we validated the structure of this model and iv) quantified the impact of the different factors on this population. Results: Results show that BCIs are associated with high levels of acceptability in the context of motor rehabilitation after stroke and that the intention to use them in that context is mainly driven by the perceived usefulness of the system. In addition, providing people with clear information regarding BCI functioning and scientific relevance had a positive influence on acceptability factors and behavioral intention. Discussion: With this paper we propose a basis (model) and a methodology that could be adapted in the future in order to study and compare the results obtained with: i) different stakeholders, i.e., patients and caregivers; ii) different populations of different cultures around the world; and iii) different targets, i.e., other clinical and non-clinical BCI applications.

Temporal Dynamics of Corticomuscular Coherence Reflects Alteration of the Central Mechanisms of Neural Motor Control in Post-Stroke Patients.

The neural control of muscular activity during a voluntary movement implies a continuous updating of a mix of afferent and efferent information. Corticomuscular coherence (CMC) is a powerful tool to explore the interactions between the motor cortex and the muscles involved in movement realization. The comparison of the temporal dynamics of CMC between healthy subjects and post-stroke patients could provide new insights into the question of how agonist and antagonist muscles are controlled related to motor performance during active voluntary movements. We recorded scalp electroencephalography activity, electromyography signals from agonist and antagonist muscles, and upper limb kinematics in eight healthy subjects and seventeen chronic post-stroke patients during twenty repeated voluntary elbow extensions and explored whether the modulation of the temporal dynamics of CMC could contribute to motor function impairment. Concomitantly with the alteration of elbow extension kinematics in post-stroke patients, dynamic CMC analysis showed a continuous CMC in both agonist and antagonist muscles during movement and highlighted that instantaneous CMC in antagonist muscles was higher for post-stroke patients compared to controls during the acceleration phase of elbow extension movement. In relation to motor control theories, our findings suggest that CMC could be involved in the online control of voluntary movement through the continuous integration of sensorimotor information. Moreover, specific alterations of CMC in antagonist muscles could reflect central command alterations of the selectivity in post-stroke patients.

Responsiveness of kinematic and clinical measures of upper-limb motor function after stroke: A systematic review and meta-analysis.

BACKGROUND: Kinematic analysis and clinical outcome measures with established responsiveness contribute to the quantified assessment of upper-limb function post-stroke, the selection of interventions and the differentiation of motor recovery patterns. OBJECTIVE: This systematic review and meta-analysis aimed to report trends in use and compare the responsiveness of kinematic and clinical measures in studies measuring the effectiveness of constraint-induced movement, trunk restraint and bilateral arm therapies for upper-limb function after stroke. METHODS: In this systematic review, randomised controlled trials implementing kinematic analysis and clinical outcome measures to evaluate the effects of therapies in post-stroke adults were eligible. We searched 8 electronic databases (MEDLINE, EMBASE, Web of Science, Scopus, CINAHL, CENTRAL, OTseeker and Pedro). Risk of bias was assessed according to the Cochrane Risk of Bias domains. A meta-analysis was conducted for repeated design measures of pre- and post-test data providing estimated standardised mean differences (SMDs). RESULTS: We included reports of 12 studies (191 participants) reporting kinematic smoothness, movement duration and efficiency, trunk and shoulder range of motion, control strategy and velocity variables in conjunction with assessment by Motor Activity Log, Fugl-Meyer Assessment and Wolf Motor Function Test. Responsiveness was higher (i.e., non-overlap of 95% confidence intervals [CIs]) for Motor Activity Log score (SMD for amount of use 1.0, 95% CI 0.75-1.25, P<0.001; SMD for quality of movement 0.96, 95% CI 0.72-1.20, P<0.001) than movement efficiency, trunk and shoulder range of motion, control strategy and peak velocity. CONCLUSION: These results are consistent with current literature supporting the use of combined kinematic and clinical measures for comprehensive and accurate evaluation of upper-limb function post-stroke. Future research should include other design trials and rehabilitation types to confirm these findings, focusing on subgroup analysis of type of rehabilitation intervention and functional levels.

Controlling for lesions, kinematics and physiological noise: impact on fMRI results of spastic post-stroke patients.

Functional magnetic resonance imaging (fMRI) is a widely used technique for assessing brain function in both healthy and pathological populations. Some factors, such as motion, physiological noise and lesion presence, can contribute to signal change and confound the fMRI data, but fMRI data processing techniques have been developed to correct for these confounding effects. Fifteen spastic subacute stroke patients underwent fMRI while performing a highly controlled task (i.e. passive extension of their affected and unaffected wrists). We investigated the impact on activation maps of lesion masking during preprocessing and first- and second-level analyses, and of adding wrist extension amplitudes and physiological data as regressors using the Statistical Parametric Mapping toolbox (SPM12). We observed a significant decrease in sensorimotor region activation after the addition of lesion masks and movement/physiological regressors during the processing of stroke patients' fMRI data. Our results demonstrate that:•The unified segmentation routine results in good normalization accuracy when dealing with stroke lesions regardless of their size;•Adding a group lesion mask during the second-level analysis seems to be a suitable option when none of the patients have lesions in target regions. Otherwise, no masking is acceptable;•Movement amplitude is a significant contributor to the sensorimotor activation observed during passive wrist extension in spastic stroke patients;•Movement features and physiological noise are relevant factors when interpreting for sensorimotor activation in studies of the motor system in patients with brain lesions. They can be added as nuisance covariates during large patient groups' analyses.

Kinematic parameters obtained with the ArmeoSpring for upper-limb assessment after stroke: a reliability and learning effect study for guiding parameter use.

BACKGROUND: After stroke, kinematic measures obtained with non-robotic and robotic devices are highly recommended to precisely quantify the sensorimotor impairments of the upper-extremity and select the most relevant therapeutic strategies. Although the ArmeoSpring exoskeleton has demonstrated its effectiveness in stroke motor rehabilitation, its interest as an assessment tool has not been sufficiently documented. The aim of this study was to investigate the psychometric properties of selected kinematic parameters obtained with the ArmeoSpring in post-stroke patients. METHODS: This study involved 30 post-stroke patients (mean age = 54.5 ± 16.4 years; time post-stroke = 14.7 ± 26.7 weeks; Upper-Extremity Fugl-Meyer Score (UE-FMS) = 40.7 ± 14.5/66) who participated in 3 assessment sessions, each consisting of 10 repetitions of the 'horizontal catch' exercise. Five kinematic parameters (task and movement time, hand path ratio, peak velocity, number of peak velocity) and a global Score were computed from raw ArmeoSpring' data. Learning effect and retention were analyzed using a 2-way repeated-measures ANOVA, and reliability was investigated using the intra-class correlation coefficient (ICC) and minimal detectable change (MDC). RESULTS: We observed significant inter- and intra-session learning effects for most parameters except peak velocity. The measures performed in sessions 2 and 3 were significantly different from those of session 1. No additional significant difference was observed after the first 6 trials of each session and successful retention was also highlighted for all the parameters. Relative reliability was moderate to excellent for all the parameters, and MDC values expressed in percentage ranged from 42.6 to 102.8%. CONCLUSIONS: After a familiarization session, the ArmeoSpring can be used to reliably and sensitively assess motor impairment and intervention effects on motor learning processes after a stroke. Trial registration The study was approved by the local hospital ethics committee in September 2016 and was registered under number 05-0916.

Cross-Modal Functional Connectivity of the Premotor Cortex Reflects Residual Motor Output After Stroke.

Stroke is known to cause widespread activation and connectivity changes resulting in different levels of functional impairment. Recovery of motor functions is thought to rely mainly on reorganizations within the sensorimotor cortex, but increasing attention is being paid to other cerebral regions. To investigate the motor task-related functional connectivity (FC) of the ipsilesional premotor cortex (PMC) and its relation to residual motor output after stroke in a population of mostly poorly recoverd patients. Twenty-four stroke patients (23 right handed, mean age = 52.4 ± 12.6 years) with varying levels of motor deficits underwent functional magnetic resonance imaging while performing different motor tasks (passive mobilization, motor execution, and motor imagery of an extension movement of the unaffected hand [UH] or affected hand [AH]). For the different motor tasks, analyses of cerebral activation and task-related FC of the ipsilesional lateral sensorimotor network (SMN), and particularly the premotor cortex (PMC), were performed. Compared with UH data, FC of the ipsilesional lateral SMN during the passive or active motor tasks involving the AH was decreased with regions of the ipsilesional SMN and was increased with regions of the bilateral frontal and the ipsilesional posterior parietal cortices such as the precuneus (Pcu). During passive wrist mobilization, FC between the ipsilesional PMC and the contralesional SMN was negatively correlated with residual motor function, whereas that with nonmotor regions such as the bilateral Pcu and the contralesional dorsolateral prefrontal cortex was positively correlated with the residual motor function. Cross-modal FC of the ipsilesional PMC may reflect compensation strategies after stroke. The results emphasize the importance of the PMC and other nonmotor regions as prominent nodes involved in reorganization processes after a stroke.

Spastic co-contraction is directly associated with altered cortical beta oscillations after stroke.

OBJECTIVE: Spastic co-contraction is a motor-disabling form of muscle overactivity occurring after a stroke, contributing to a limitation in active movement and a certain level of motor impairment. The cortical mechanisms underlying spastic co-contraction remain to be more fully elucidated, the present study aimed to investigate the role of the cortical beta oscillations in spastic co-contraction after a stroke. METHOD: We recruited fifteen post-stroke participants and nine healthy controls. The participants were asked to perform active elbow extensions. In the study, multimodal analysis was performed to combine the evaluation of three-dimensional elbow kinematics, the elbow muscles electromyographic activations, and the cortical oscillatory activity. RESULTS: The movement-related beta desynchronization was significantly decreased in post-stroke participants compared to healthy participants. We found a significant correlation between the movement-related beta desynchronization and the elbow flexors activation during the active elbow extension in post-stroke participants. When compared to healthy participants, post-stroke participants exhibited significant alterations in the elbow kinematics and greater muscle activation levels. CONCLUSIONS: Cortical beta oscillation alterations may reflect an important neural mechanism underlying spastic co-contraction after a stroke. SIGNIFICANCE: Measuring the cortical oscillatory activity could be useful to further characterize neuromuscular plasticity induced by recovery or therapeutic interventions.