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1.
Dev Med Child Neurol ; 65(9): 1157-1173, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36750309

RESUMO

AIM: To explore altered structural and functional connectivity and network organization in cerebral palsy (CP), by clinical CP subtype (unilateral spastic, bilateral spastic, dyskinetic, and ataxic CP). METHOD: PubMed and Embase databases were systematically searched. Extracted data included clinical characteristics, analyses, outcome measures, and results. RESULTS: Sixty-five studies were included, of which 50 investigated structural connectivity, and 20 investigated functional connectivity using functional magnetic resonance imaging (14 studies) or electroencephalography (six studies). Five of the 50 studies of structural connectivity and one of 14 of functional connectivity investigated whole-brain network organization. Most studies included patients with unilateral spastic CP; none included ataxic CP. INTERPRETATION: Differences in structural and functional connectivity were observed between investigated clinical CP subtypes and typically developing individuals on a wide variety of measures, including efferent, afferent, interhemispheric, and intrahemispheric connections. Directions for future research include extending knowledge in underrepresented CP subtypes and methodologies, evaluating the prognostic potential of specific connectivity and network measures in neonates, and understanding therapeutic effects on brain connectivity.


Assuntos
Paralisia Cerebral , Recém-Nascido , Humanos , Espasticidade Muscular , Encéfalo , Imageamento por Ressonância Magnética/métodos
2.
J Neurol Phys Ther ; 47(3): 127-138, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36897200

RESUMO

BACKGROUND AND PURPOSE: Benign paroxysmal positional vertigo (BPPV) is one of the most common vestibular disorders, and is treated effectively with particle repositioning maneuvers (PRM). The aim of this study was to assess the influence of BPPV and treatment effects of PRM on gait, falls, and fear of falling. METHODS: Three databases and the reference lists of included articles were systematically searched for studies comparing gait and/or falls between (1) people with BPPV (pwBPPV) and controls and (2) pre- and posttreatment with PRM. The Joanna Briggs Institute critical appraisal tools were used to assess risk of bias. RESULTS: Twenty of the 25 included studies were suitable for meta-analysis. Quality assessment resulted in 2 studies with high risk of bias, 13 with moderate risk, and 10 with low risk. PwBPPV walked slower and demonstrated more sway during tandem walking compared with controls. PwBPPV also walked slower during head rotations. After PRM, gait velocity during level walking increased significantly, and gait became safer according to gait assessment scales. Impairments during tandem walking and walking with head rotations did not improve. The number of fallers was significantly higher for pwBPPV than for controls. After treatment, the number of falls, number of pwBPPV who fell, and fear of falling decreased. DISCUSSION AND CONCLUSIONS: BPPV increases the odds of falls and negatively impacts spatiotemporal parameters of gait. PRM improves falls, fear of falling, and gait during level walking. Additional rehabilitation might be necessary to improve gait while walking with head movements or tandem walking.Video Abstract available for more insights from the authors (see the Supplemental Digital Content Video, available at: http://links.lww.com/JNPT/A421 ).


Assuntos
Vertigem Posicional Paroxística Benigna , Medo , Humanos , Vertigem Posicional Paroxística Benigna/terapia , Marcha , Caminhada
3.
Sensors (Basel) ; 23(16)2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37631706

RESUMO

INTRODUCTION: Spatiotemporal gait parameters, e.g., gait stride length, are measurements that are classically derived from instrumented gait analysis. Today, different solutions are available for gait assessment outside the laboratory, specifically for spatiotemporal gait parameters. Such solutions are wearable devices that comprise an inertial measurement unit (IMU) sensor and a microcontroller (MCU). However, these existing wearable devices are resource-constrained. They contain a processing unit with limited processing and memory capabilities which limit the use of machine learning to estimate spatiotemporal gait parameters directly on the device. The solution for this limitation is embedded machine learning or tiny machine learning (tinyML). This study aims to create a machine-learning model for gait stride length estimation deployable on a microcontroller. MATERIALS AND METHOD: Starting from a dataset consisting of 4467 gait strides from 15 healthy people, measured by IMU sensor, and using state-of-the-art machine learning frameworks and machine learning operations (MLOps) tools, a multilayer 1D convolutional float32 and int8 model for gait stride length estimation was developed. RESULTS: The developed float32 model demonstrated a mean accuracy and precision of 0.23 ± 4.3 cm, and the int8 model demonstrated a mean accuracy and precision of 0.07 ± 4.3 cm. The memory usage for the float32 model was 284.5 kB flash and 31.9 kB RAM. The int8 model memory usage was 91.6 kB flash and 13.6 kB RAM. Both models were able to be deployed on a Cortex-M4F 64 MHz microcontroller with 1 MB flash memory and 256 kB RAM. CONCLUSIONS: This study shows that estimating gait stride length directly on a microcontroller is feasible and demonstrates the potential of embedded machine learning, or tinyML, in designing wearable sensor devices for gait analysis.


Assuntos
Análise da Marcha , Marcha , Humanos , Algoritmos , Córtex Cerebral , Aprendizado de Máquina
4.
J Neuroeng Rehabil ; 18(1): 47, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33691710

RESUMO

BACKGROUND: While walking, people swing their arms in a specific pattern. This specific arm swing pattern during walking has shown to have a beneficial effect on gait as it reduces walking energy cost and optimizes balance. In several patient populations the arm movements can be directly affected (e.g. in patients with acquired brain injury (ABI)), which in turn has a negative effect on their gait pattern, balance and energy cost of walking. MAIN TEXT: In December 2019, Kahn et al. published a paper in JNER concerning the quantification of upper limb associated reactions (ARs) during walking in people with ABI. ARs are defined as "an effort-dependent phenomenon causing an involuntary increase in upper limb muscle tone, with awkward and uncomfortable postures". These upper limb ARs appear often in patients with ABI and can have an important effect on their gait. The authors calculated kinematic measures using three-dimensional gait analysis relating to range of motion, variability and mean position over the gait cycle for the different upper limb joints (shoulder, elbow, wrist) during self-selected steady-state walking. Based on differences they found between an ABI cohort and healthy control cohort, the authors concluded that they were able to quantify ARs during walking in this population. This calculation, however, is not specific for upper limb ARs. In fact, the authors calculated general measures of arm posture (e.g. mean position over the gait cycle) or arm movement (e.g. range of motion and variability) during gait. Previous research has already indicated that other factors than ARs can influence the posture or movement of the arm during gait in patients with brain injury, such as voluntary compensations for gait instability and contractures or spasticity of upper arm muscles. Yet, it is not possible to disentangle the different causes of the altered arm posture during steady-state walking based on the proposed measures. CONCLUSION: The kinematic arm measures proposed by Kahn et al. (J Neuroeng Rehabil 16(1):160, 2019) are not a direct measure of ARs, but provide a quantification of overall deviation of arm posture or movement during gait. Depending on the specific study design these measures may provide insights in ARs.


Assuntos
Lesões Encefálicas , Caminhada , Braço , Fenômenos Biomecânicos , Marcha , Humanos , Movimento , Extremidade Superior
5.
Dev Med Child Neurol ; 60(9): 866-883, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29512110

RESUMO

AIM: The aim of this systematic review was to investigate the effects of functional gait training on walking ability in children and young adults with cerebral palsy (CP). METHOD: The review was conducted using standardized methodology, searching four electronic databases (PubMed, Embase, CINAHL, Web of Science) for relevant literature published between January 1980 and January 2017. Included studies involved training with a focus on actively practising the task of walking as an intervention while reporting outcome measures relating to walking ability. RESULTS: Forty-one studies were identified, with 11 randomized controlled trials included. There is strong evidence that functional gait training results in clinically important benefits for children and young adults with CP, with a therapeutic goal of improved walking speed. Functional gait training was found to have a moderate positive effect on walking speed over standard physical therapy (effect size 0.79, p=0.04). Further, there is weaker yet relatively consistent evidence that functional gait training can also benefit walking endurance and gait-related gross motor function. INTERPRETATION: There is promising evidence that functional gait training is a safe, feasible, and effective intervention to target improved walking ability in children and young adults with CP. The addition of virtual reality and biofeedback can increase patient engagement and magnify effects. WHAT THIS PAPER ADDS: Functional gait training is a safe, feasible, and effective intervention to improve walking ability. Functional gait training shows larger positive effects on walking speed than standard physical therapy. Walking endurance and gait-related gross motor function can also benefit from functional gait training. Addition of virtual reality and biofeedback shows promise to increase engagement and improve outcomes.


Assuntos
Paralisia Cerebral/reabilitação , Terapia por Exercício , Marcha , Adolescente , Paralisia Cerebral/fisiopatologia , Criança , Humanos , Resultado do Tratamento , Adulto Jovem
6.
Exerc Sport Sci Rev ; 42(1): 23-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24188982

RESUMO

Backward locomotion is used increasingly in sports and rehabilitation. However, it is unclear whether training effects of backward walking (BW)/backward running (BR) can be transferred simply to forward walking (FW)/forward running (FR). This touches on the question whether the same neural substrate can generate FW and BW. The available evidence suggests that BW uses the same rhythm circuitry but additionally requires specialized control circuits.


Assuntos
Exercício Físico , Marcha , Reabilitação , Humanos
7.
Eur J Appl Physiol ; 114(4): 743-50, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24384984

RESUMO

PURPOSE: The most commonly used propulsion method for handcycling is moving the arms symmetrically. Previous studies indicated that during outdoor handcycling symmetrical arm movements are more efficient. During locomotor movements, however, arm movements are performed asymmetrically in combination with leg movements. We questioned which combination of arm and leg movements is more efficient during combined arm and leg cycling for stationary use. METHODS: Twenty-five able-bodied adults performed eight submaximal tests of 6 min on a hybrid handcycle at three incremental gears during four different conditions ('arms only' and 'arms & legs' with arms symmetrical and asymmetrical). Oxygen uptake (VO2), heart rate (HR) and Borg score (Borg) were assessed. RESULTS: Increasing workload resulted in significant increases in VO2 (16 W: 13.0 ± 2.4 ml kg(-1) min(-1), 31 W: 14.5 ± 2.9, 49 W: 15.5 ± 2.8; p < 0.001) and Borg (16 W: 7.7 ± 1.7 points, 31 W: 8.6 ± 1.9, 49 W: 9.5 ± 1.9; p < 0.001). During 'arms only', no differences were found in exercise intensity between symmetrical and asymmetrical movements. Contrarily, during 'arms & legs', both VO2 (p < 0.001) and Borg (p = 0.001) were significantly lower for the asymmetrical (VO2: 13.8 ± 2.6 ml kg(-1) min(-1), Borg: 8.1 ± 1.6 points) compared to the symmetrical condition (VO2: 14.9 ± 2.8, Borg: 9.1 ± 2.0). CONCLUSIONS: Results indicated that asymmetrical arm movements, especially in combination with leg movements, represented the most efficient condition on a stationary hybrid handcycle. The current results suggest that neural energy costs are lower when moving in the preferred (asymmetrical) coordination when no steering is required. These findings may have implications for stationary arm & leg cycling rehabilitation and tricycle adaptations in patients with spinal cord injury.


Assuntos
Braço/fisiologia , Terapia por Exercício/métodos , Perna (Membro)/fisiologia , Movimento , Adulto , Ciclismo , Feminino , Frequência Cardíaca , Humanos , Masculino , Consumo de Oxigênio
8.
Res Dev Disabil ; 147: 104694, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382234

RESUMO

BACKGROUND: Children with Developmental Coordination Disorder (DCD) often (<87 %) experience postural control problems, impacting all levels of the International Classification of Functioning, Disability and Health (ICF) including their daily participation, self-esteem and mental health. Due to the multisystemic nature of postural control, comprehensive therapy should target all systems which is currently not the case. Highly intensive therapy is effective and commonly used in pediatric populations, but has not been explored yet to train postural control in children with DCD. AIMS: To investigate the effects of a highly intensive functional balance therapy camp at all ICF levels in children with DCD. METHODS AND PROCEDURES: The effects on postural control, muscle activity, brain alterations, self-perceived competence, self-identified goals, gross motor activities and participation are evaluated. Participants are assessed pre- and post-intervention, including a 3 months follow-up. Forty-eight children with DCD, aged 6-12 years old, receive 40 h of comprehensive balance training. This intervention is fun, individually tailored, targets all postural control systems, implements different motor learning strategies and includes both individual and group activities. CONCLUSION: Novel insights into the effects of a highly intensive comprehensive balance therapy camp designed for children with DCD will be gained at all levels of the ICF.


Assuntos
Transtornos das Habilidades Motoras , Criança , Humanos , Destreza Motora/fisiologia , Terapia por Exercício/métodos , Autoimagem , Equilíbrio Postural/fisiologia
9.
Hum Mov Sci ; 93: 103174, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38160498

RESUMO

BACKGROUND: Persons after stroke present with an altered arm swing during walking. Given the known influence of the arm swing on gait, it is important to identify the characteristics of persons with stroke with different arm-to-leg coordination patterns during walking. METHODS: Twenty-five persons after stroke walked on a self-paced treadmill at comfortable walking speed. The frequency of shoulder movements per stride was detected by Fast Fourier transform analysis on the kinematic data for hemiplegic shoulder movements in the sagittal plane. An independent-sample t-test or Mann-Whitney U test was used to compare clinical and biomechanical parameters between identified subgroups. RESULTS: Two earlier described subgroups based on the number of shoulder flexion-extension movements during one stride could be confirmed. Participants in the 1:1 ratio subgroup (one arm swing during one stride, N = 15) presented with a less upper limb impairment and less spasticity of the elbow extensors (p = 0.012) than the participants in the 2:1 ratio subgroup (two arm swings during one stride, N = 9). Although not significant, the participants in the 1:1 subgroup also seemed to have less spasticity of the shoulder internal rotators (p = 0.06) and a less walking variability based on the standard deviation of the step width. Further research on a greater sample should confirm these findings. CONCLUSION: Fast Fourier transform analysis was used to identify subgroups based on sagittal shoulder kinematics during walking. The clinical and gait related differences between the identified subgroups can be taken into account in future research investigating post-stroke gait interventions aiming to improve the arm swing.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Marcha , Caminhada , Velocidade de Caminhada , Fenômenos Biomecânicos
10.
Neurorehabil Neural Repair ; 38(2): 75-86, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38229519

RESUMO

BACKGROUND: Gait characteristics and their changes during the 6-minute walking test (6MWT) in people with multiple sclerosis (pwMS) have been described in the literature, which one may refer to as walking fatigability in the body function level of the International Classification of Functioning, Disability, and Health. However, whether these metrics are reliable is unknown. OBJECTIVE: To investigate the between-day reliability of the gait characteristics and their changes in pwMS and healthy controls (HCs). METHODS: Forty-nine pwMS (EDSS 4.82 ± 1.22 and 54.7 ± 9.36 years) and 23 HCs (50.6 ± 6.1 years) performed the 6MWT, as fast as possible but safely while wearing Inertial Measurement Units. Gait characteristics were measured in the pace, rhythm, variability, asymmetry, kinematics, coordination, and postural control domains and were obtained in intervals of 1 minute during the 6MWT. In addition, gait characteristics change in the last minute compared with the first minute were calculated for all gait variables using a fatigability index (ie, distance walking index). The intraclass correlation coefficient (ICC), Bland-Altman Plots, and Standard error of measurement were applied to investigate reliability. RESULTS: Reliability of gait characteristics, minute-by-minute, and for their changes (ie, using the fatigability index) ranged from poor to excellent (pwMS: ICC 0.46-0.96; HC: ICC 0.09-0.97 and pwMS: ICC 0-0.72; HC: ICC 0-0.77, respectively). CONCLUSION: Besides coordination, at least 1 variable of each gait domain showed an ICC of moderate or good reliability for gait characteristics changes in both pwMS and HC. These metrics can be incorporated into future clinical trials and research on walking fatigability.Clinical Trial Registration: NCT05412043.


Assuntos
Esclerose Múltipla , Humanos , Esclerose Múltipla/complicações , Reprodutibilidade dos Testes , Marcha , Caminhada , Teste de Caminhada , Fadiga/diagnóstico , Fadiga/etiologia
11.
J Sport Health Sci ; 12(2): 219-225, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35390537

RESUMO

BACKGROUND: Proprioceptive accuracy refers to the individual's ability to perceive proprioceptive information, that is, the information referring to the actual state of the locomotor system, which originates from mechanoreceptors located in various parts of the locomotor system and from tactile receptors located in the skin. Proprioceptive accuracy appears to be an important aspect in the evaluation of sensorimotor functioning; however, no widely accepted standard assessment exists. In this systematic review, our goal was to identify and categorize different methods that are used to assess different aspects of proprioceptive accuracy. METHODS: A literature search was conducted in 5 different databases (PubMed, SPORTDiscus, PsycINFO, ScienceDirect, and SpringerLink). RESULTS: Overall, 1139 scientific papers reporting 1346 methods were included in this review. The methods assess 8 different aspects of proprioception: (a) the perception of joint position, (b) movement and movement extent, (c) trajectory, (d) velocity, and the sense of (e) force, (f) muscle tension, (g) weight, and (h) size. They apply various paradigms of psychophysics (i.e., the method of adjustment, constant stimuli, and limits). CONCLUSION: As the outcomes of different tasks with respect to various body parts show no associations (i.e., proprioceptive accuracy is characterized by site-specificity and method-specificity), the appropriate measurement method for the task needs to be chosen based on theoretical considerations and/or ecological validity.


Assuntos
Movimento , Propriocepção , Propriocepção/fisiologia , Movimento/fisiologia
12.
Mult Scler Relat Disord ; 70: 104479, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36608537

RESUMO

BACKGROUND: Persons with Multiple Sclerosis (pwMS) frequently experience walking difficulties, often expressed as a slower walking speed during the 6 Minute Walking Test (6MWT). In addition, slower walking speeds are also related to higher levels of perceived exertion. PwMS are also known to have a higher energetic Cost of walking (Cw) and may experience muscle fatigue during prolonged walking. In this study, we aimed to explore changes in Rate of Perceived Exertion (RPE) and the Cw within participants during the 6MWT in pwMS. Additionally, concomitant changes in the mean and variability of gait characteristics and changes in muscle activation describing muscle fatigue were assessed. METHODS: The 6MWT was performed on an instrumented treadmill while three-dimensional motion capture and gas exchange were measured continuously. RPE on the 6-20 borg-scale was questioned directly before and after the 6MWT. Cost of walking was expressed in Joules/kg/m. Muscle fatigue was assessed by increases in Root Median Square (RMdS) and decreases in Median Frequency (MF) of the recorded EMGs. Wilcoxon-Signed Rank test was used to assess a difference in RPE before and after the 6MWT. Linear mixed models, while controlling for walking speed, were used to assess changes in Cw, mean and variability of gait characteristics and RMdS and MF of muscle activation. RESULTS: 28 pwMS (23 females, mean ± standard deviation age 46 ± 10 years, height 1.69 ± 0.08 meter, weight 76 ± 18 kilogram, EDSS 2.7 ± 1.3) were included. Although the RPE increased from 8 to 12, no changes in Cw were found. Walking speed was the only spatiotemporal parameter which increased during the 6MWT and RMdS of the gastrocnemius and tibialis anterior muscles increased. The soleus muscle decreased in MF over time. CONCLUSION: The increases in RPE and walking speed was not accompanied by a change in Cw during the 6MWT which indicates that the perceived exertion was not accompanied by an increased physical exertion. Changes in muscle activation might give an indication for muscle fatigue but were inconclusive. Although the 6MWT reflects daily life walking challenges for pwMS, this test did not show the expected changes in gait parameters in our sample.


Assuntos
Esclerose Múltipla , Fadiga Muscular , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Caminhada/fisiologia , Marcha/fisiologia , Teste de Caminhada/métodos
13.
Ann Phys Rehabil Med ; 66(4): 101729, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36669385

RESUMO

BACKGROUND: Postural control deficits are one of the most common impairments treated in pediatric physiotherapeutic practice. Adequate evaluation of these deficits is imperative to identify postural control deficits, plan treatment and assess efficacy. Currently, there is no gold standard evaluation for postural control deficits. However, the number of studies investigating the psychometric properties of functional pediatric postural control tests has increased significantly. OBJECTIVE: To facilitate the selection of an appropriate pediatric functional postural control test in research and clinical practice. METHODS: Systematic review following the PRISMA guidelines. PubMed, Web of Science and Scopus were systematically searched (last update: June 2022; PROSPERO: CRD42021246995). Studies were selected using the PICOs-method (pediatric populations (P), functional assessment tools for postural control (I) and psychometric properties (O). The risk of bias was rated with the COSMIN checklist and the level of evidence was determined with GRADE. For each test, the postural control systems were mapped, and the psychometric properties were extracted. RESULTS: Seventy studies investigating 26 different postural control tests were included. Most children were healthy or had cerebral palsy. Overall, the evidence for all measurement properties was low to very low. Most tests (95%) showed good reliability (ICC>0.70), but inconsistent validity results. Structural validity, internal consistency and responsiveness were only available for 3 tests. Only the Kids-BESTest and FAB covered all postural control systems. CONCLUSION: Currently, 2 functional tests encompass the entire construct of postural control. Although reliability is overall good, validity results depend on task, age and pathology. Future research should focus on test batteries and should particularly explore structural validity and responsiveness in different populations with methodologically strong study designs.


Assuntos
Paralisia Cerebral , Equilíbrio Postural , Humanos , Criança , Psicometria/métodos , Reprodutibilidade dos Testes , Projetos de Pesquisa
14.
J Neurophysiol ; 107(12): 3385-96, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22423005

RESUMO

Leg kinematics during backward walking (BW) are very similar to the time-reversed kinematics during forward walking (FW). This suggests that the underlying muscle activation pattern could originate from a simple time reversal, as well. Experimental electromyography studies have confirmed that this is the case for some muscles. Furthermore, it has been hypothesized that muscles showing a time reversal should also exhibit a reversal in function [from accelerating the body center of mass (COM) to decelerating]. However, this has not yet been verified in simulation studies. In the present study, forward simulations were used to study the effects of muscles on the acceleration of COM in FW and BW. We found that a reversal in function was indeed present in the muscle control of the horizontal movement of COM (e.g., tibialis anterior and gastrocnemius). In contrast, muscles' antigravity contributions maintained their function for both directions of movement. An important outcome of the present study is therefore that similar muscles can be used to achieve opposite functional demands at the level of control of the COM when walking direction is reversed. However, some muscles showed direction-specific contributions (i.e., dorsiflexors). We concluded that the changes in muscle contributions imply that a simple time reversal would be insufficient to produce BW from FW. We therefore propose that BW utilizes extra elements, presumably supraspinal, in addition to a common spinal drive. These additions are needed for propulsion and require a partial reconfiguration of lower level common networks.


Assuntos
Músculo Esquelético/inervação , Músculo Esquelético/fisiologia , Caminhada/fisiologia , Aceleração , Adulto , Fenômenos Biomecânicos , Simulação por Computador , Eletromiografia , Feminino , Humanos , Perna (Membro)/fisiologia , Masculino , Desempenho Psicomotor/fisiologia , Adulto Jovem
15.
Hum Mov Sci ; 82: 102930, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35123153

RESUMO

During standing, posture can be controlled by accelerating the Center of Mass (CoM) through shifting the center of pressure (CoP) within the base of support by applying ankle moments ("CoP mechanism"), or through the "counter-rotation mechanism", i.e., changing the angular momentum of segments around the CoM to change the direction of the ground reaction force. Postural control develops over the lifespan; at both the beginning and the end of the lifespan adequate postural control appears more challenging. In this study, we aimed to assess mediolateral balance performance and the related use of the postural control mechanisms in children, older adults and younger adults when standing on different (unstable) surfaces. Sixteen pre-pubertal children (6-9y), 17 younger adults (18-24y) and eight older adults (65-80y) performed bipedal upright standing trials of 16 s on a rigid surface and on three balance boards that could freely move in the frontal plane, varying in height (15-19 cm) of the surface of the board above the point of contact with the floor. Full body kinematics (16 segments, 48 markers, using SIMI 3D-motion analysis system (GmbH) and DeepLabCut and Anipose) were retrieved. Performance related outcome measures, i.e., the number of trials with balance loss and the Root Mean Square (RMS) of the time series of the CoM acceleration, the contributions of the CoP mechanism and the counter-rotation mechanism to the CoM acceleration in the frontal plane and selected kinematic measures, i.e. the orientation of the board and the head and the Mean Power Frequency (MPF) of the balance board orientation and the CoM acceleration were determined. Balance loss only occurred when standing on the highest balance board, twice in one older adult once in one younger adult. In children and older adults, the RMS of the CoM accelerations were larger, corresponding to poorer balance performance. Across age groups and conditions, the contribution of the CoP mechanism to the total CoM acceleration was much larger than that of the counter-rotation mechanisms, ranging from 94% to 113% vs 23% to 38% (with totals higher than 100% indicating opposite effects of both mechanisms). Deviations in head orientation were small compared to deviations in balance board orientation. We suggest that the CoP mechanism is dominant, since the counter-rotation mechanism would conflict with stabilizing the orientation of the head in space.


Assuntos
Equilíbrio Postural , Postura , Aceleração , Idoso , Fenômenos Biomecânicos , Criança , Humanos , Posição Ortostática
16.
J Biomech ; 136: 111073, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35390646

RESUMO

During walking, the center of mass (CoM) position can be controlled relative to the base of support by shifts of the center of pressure through modulation of foot placement and ankle moments (CoP-mechanism). An additional mechanism is the counter-rotation mechanism, i.e. changing the angular momentum of segments around the CoM to change the direction of the ground reaction force. It is unknown if, and how, humans use the counter-rotation mechanism to accelerate the CoM during walking and how this interacts with the CoP-mechanism. Thirteen healthy adults walked on a treadmill, while full-body kinematic and force plate data were obtained. The contributions of the CoP and the counter-rotation mechanisms to CoM-acceleration during steady-state walking, walking on LesSchuh (i.e. constraining mediolateral CoP shifts underneath the stance foot) and walking on LesSchuh at 50% of normal step width, constraining both foot placement and ankle mechanisms (LesSchuh50%) were calculated. The within-stride variance in CoM-acceleration due to the CoP-mechanism was smaller and the within-stride variance in CoM-acceleration due to the counter-rotation mechanism was larger during LesSchuh50% compared to steady-state walking. This suggests that the counter-rotation mechanism is used to stabilize gait when needed, but the CoP-mechanism was the main contributor to the total CoM-acceleration. The use of the counter-rotation mechanism may be limited, because angular accelerations ultimately need to be reversed and because of interference with other task constraints, such as head stabilization and preventing interference with the gait pattern.


Assuntos
Tornozelo , , Adulto , Fenômenos Biomecânicos , Marcha , Humanos , Rotação , Caminhada
17.
Disabil Rehabil ; 44(20): 5990-5999, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34365883

RESUMO

PURPOSE: Previous studies investigating the effectiveness of exergame balance-training (using video-games) in children with cerebral palsy (CP) yielded inconsistent results that could be related to underpowered studies. Therefore, in this multicenter intervention study, we investigated whether exergaming improves balance clinically in spastic CP. MATERIALS AND METHODS: In total, 35 children with unilateral or bilateral spastic CP (GMFCS-level I-II) were included (age-range: 7-16 years); 16 at VUMC (trial: NTR6034), 19 at UHG (trial: NCT03219112). All participants received care as usual. The intervention group (n = 24) additionally performed exergame-training; 6-8 weeks home-based X-box One Kinect training focused on balance. Balance performance was assessed with the pediatric balance scale (PBS) and two subscales of the Bruininks-Oseretsky Test of Motor Proficiency-2nd edition ("balance" [BOTbal] and "running speed and agility" [BOTrsa]). Mixed model ANOVAs with between and within factors were used to test differences between and within groups. RESULTS: On group level, no post-intervention differences were found between the intervention and control group (PBS: p = 0.248, ηp2 = 0.040; BOTbal: p = 0.374, ηp2 = 0.024; BOTrsa: p = 0.841, ηp2 = 0.001). Distribution of CP-symptoms (unilateral versus bilateral) did not affect training (PBS: p = 0.373, ηp2 = 0.036; BOTbal: p = 0.127, ηp2 = 0.103; BOTrsa: p = 0.474, ηp2 = 0.024). Children with low baseline balance performance (based on PBS) in the intervention group showed improvements in balance performance after training (PBS: p = 0.003, ηp2 = 0.304; BOTbal: p = 0.008, ηp2 = 0.258), whereas children with high baseline balance performance did not. CONCLUSIONS: This exergame-training resulted in balance improvements for the current population of CP that had a low baseline function.IMPLICATIONS FOR REHABILITATIONExergame-training (training using video-games) shows mixed results in children with cerebral palsy (CP).Children with spastic CP (GMFCS level I-II) with a high baseline balance-level did not show functional balance improvements after this home-based exergame-training, suggesting that these children should not be enrolled in this type of exergame-training protocol.Children with spastic CP (GMFCS level I-II) with a low baseline balance-level showed clinically relevant functional balance improvements after this home-based exergame-training, suggesting that these children can benefit from enrolment in this type of exergame-training protocol to improve their balance.The distribution of CP-symptoms did not affect the effectiveness of this balance exergame-training in children with spastic CP with GMFCS-level I and II.


Assuntos
Paralisia Cerebral , Jogos de Vídeo , Adolescente , Criança , Jogos Eletrônicos de Movimento , Humanos , Espasticidade Muscular
18.
Neurorehabil Neural Repair ; 35(6): 486-500, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33847188

RESUMO

BACKGROUND: Persons with multiple sclerosis (pwMS) experience walking impairments, characterized by decreased walking speeds. In healthy subjects, the self-selected walking speed is the energetically most optimal. In pwMS, the energetically most optimal walking speed remains underexposed. Therefore, this review aimed to determine the relationship between walking speed and energetic cost of walking (Cw) in pwMS, compared with healthy subjects, thereby assessing the walking speed with the lowest energetic cost. As it is unclear whether the Cw in pwMS differs between overground and treadmill walking, as reported in healthy subjects, a second review aim was to compare both conditions. METHOD: PubMed and Web of Science were systematically searched. Studies assessing pwMS, reporting walking speed (converted to meters per second), and reporting oxygen consumption were included. Study quality was assessed with a modified National Heart, Lung and Blood Institute checklist. The relationship between Cw and walking speed was calculated with a second-order polynomial function and compared between groups and conditions. RESULTS: Twenty-nine studies were included (n = 1535 pwMS) of which 8 included healthy subjects (n = 179 healthy subjects). PwMS showed a similar energetically most optimal walking speed of 1.44 m/s with a Cw of 0.16, compared with 0.14 mL O2/kg/m in healthy subjects. The most optimal walking speed in treadmill was 1.48 m/s, compared with 1.28 m/s in overground walking with a similar Cw. CONCLUSION: Overall, the Cw is elevated in pwMS but with a similar energetically most optimal walking speed, compared with healthy subjects. Treadmill walking showed a similar most optimal Cw but a higher speed, compared with overground walking.


Assuntos
Metabolismo Energético/fisiologia , Esclerose Múltipla/fisiopatologia , Velocidade de Caminhada/fisiologia , Humanos
19.
Gait Posture ; 83: 268-279, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33227605

RESUMO

BACKGROUND: Although it is recognized that the majority of children with developmental coordination disorder (DCD) have balance deficits, comprehensive insights into which balance domains are affected, are still lacking in literature. RESEARCH QUESTION: To what extent is balance control deficient in individuals with DCD compared to controls? METHODS: Pubmed, Scopus and Web of Science were systematically searched. Risk of bias was assessed with the Scottish Intercollegiate Guidelines Network checklist for case-control studies. Mean and standard deviations characterizing balance control were extracted to calculate standardized mean differences (SMD) and pooled, if possible, using Review Manager. RESULTS: The results of 31 studies (1152 individuals with DCD, 1103 typically developing (TD) peers, mean age 10.4 years old) were extracted of which 17 were used for meta-analysis. The mean SMD for the balance subscale of the Movement Assessment Battery for Children was 1.63 (pooled 95 %CI =[1.30;1.97]), indicating children with DCD to perform significantly poorer than their TD peers. Force plate studies also revealed that children with DCD present with a larger sway path during bipedal stance with eyes closed (pooled mean SMD = 0.55; 95 %CI=[0.32;0.78]). Children with DCD tend to have direction-specific limited stability limits and task-independent delayed onset of anticipatory postural adjustments. INTERPRETATION: Children with DCD perform poorer on different domains of balance compared to TD peers. Future research should focus on comprehensive balance assessment in these children, preferably using a longitudinal design.


Assuntos
Transtornos das Habilidades Motoras/complicações , Equilíbrio Postural/fisiologia , Criança , Feminino , Humanos , Masculino
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