Model Predictive Control-based gait pattern generation for wearable exoskeletons.

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Wang, Letian; van Asseldonk, Edwin H F; van der Kooij, Herman

2011-01-01

This paper introduces a new method for controlling wearable exoskeletons that do not need predefined joint trajectories. Instead, it only needs basic gait descriptors such as step length, swing duration, and walking speed. End point Model Predictive Control (MPC) is used to generate the online joint trajectories based on these gait parameters. Real-time ability and control performance of the method during the swing phase of gait cycle is studied in this paper. Experiments are performed by helping a human subject swing his leg with different patterns in the LOPES gait trainer. Results show that the method is able to assist subjects to make steps with different step length and step duration without predefined joint trajectories and is fast enough for real-time implementation. Future study of the method will focus on controlling the exoskeletons in the entire gait cycle. © 2011 IEEE

Non-surgical management of a pediatric "intoed" gait pattern - a systematic review of the current best evidence.

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Uden, Hayley; Kumar, Saravana

2012-01-01

An intoed gait pattern is one of the most common referrals for children to an orthopedic consultation. Parental concern as to the aesthetics of the child's gait pattern and/or its symptomatic nature will primarily drive these referrals during a child's early developmental years. Whilst some of these referrals prove to be the result of a normal growth variant, some children will present with a symptomatic intoed gait pattern. Various treatments, both conservative and surgical, have been proposed including: braces, wedges, stretches and exercises, shoe modifications, and surgical procedures. However, which treatments are effective and justified in the management of this condition is not clear within the literature. The aim of this systematic review was to therefore identify and critique the best available evidence for the non-surgical management of an intoed gait pattern in a pediatric population. A systematic review was conducted of which only experimental studies investigating a management option for an intoeing gait pattern were included. Studies needed to be written in English, pertaining to a human pediatric population, and published within a peer reviewed journal. Electronic databases were searched: Ovid (Medline), EMBASE, AMED, PubMed, SportDiscus, CINAHL, and Cochrane Library. The National Health and Medical Research Council's designation of levels of hierarchy and the Critical Appraisal Skills Programme cohort studies critical appraisal tool were used. Five level IV studies were found. The studies were of varied quality and with mixed results. Gait plates, physiologic/standardized shoes, and orthotic devices (with gate plate extension) were shown to produce a statistically significant improvement to an intoed gait pattern. Shoe wedges, torqheels, and a leather counter splint were not able to reduce an intoed gait pattern. There is limited evidence to inform the non-surgical management of a pediatric intoed gait pattern. The body of evidence that does exist

Modification of hemiplegic compensatory gait pattern by symmetry-based motion controller of HAL.

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Kawamoto, Hiroaki; Kadone, Hideki; Sakurai, Takeru; Sankai, Yoshiyuki

2015-01-01

As one of several characteristics of hemiplegic patients after stroke, compensatory gait caused by affected limb is often seen. The purpose of this research is to apply a symmetry-based controller of a wearable type lower limb robot, Hybrid Assistive Limb (HAL) to hemiplegic patients with compensatory gait, and to investigate improvement of gait symmetry. The controller is designed respectively for swing phase and support phase according to characteristics of hemiplegic gait pattern. The controller during swing phase stores the motion of the unaffected limb and then provides motion support on the affected limb during the subsequent swing using the stored pattern to realize symmetric gait based on spontaneous limb swing. Moreover, the controller during support phase provides motion to extend hip and knee joints to support wearer's body. Clinical tests were conducted in order to assess the modification of gait symmetry. Our case study involved participation of one chronic stroke patient who performs abnormally-compensatory gait for both of the affected and unaffected limbs. As a result, the patient's gait symmetry was improved by providing motion support during the swing phase on the affected side and motion constraint during the support phase on the unaffected side. The study showed promising basis for the effectiveness of the controller for the future clinical study.

Normal human gait patterns in Peruvian individuals: an exploratory assessment using VICON motion capture system

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Dongo, R.; Moscoso, M.; Callupe, R.; Pajaya, J.; Elías, D.

2017-11-01

Gait analysis is of clinical relevance for clinicians. However, normal gait patterns used in foreign literature could be different from local individuals. The aim of this study was to determine the normal gait patterns and parameters of Peruvian individuals in order to have a local referent for clinical assessments and making diagnosis and treatment Peruvian people with lower motor neuron injuries. A descriptive study with 34 subjects was conducted to assess their gait cycle. VICON® cameras were used to capture body movements. For the analyses, we calculated spatiotemporal gait parameters and average angles of displacement of the hip, knee, and ankle joints with their respective 95% confidence intervals. The results showed gait speed was 0.58m/s, cadence was 102.1steps/min, and the angular displacement of the hip, knee and ankle joints were all lower than those described in the literature. In the graphs, gait cycles were close to those reported in previous studies, but the parameters of speed, cadence and angles of displacements are lower than the ones shown in the literature. These results could be used as a better reference pattern in the clinical setting.

An Ambulatory Method of Identifying Anterior Cruciate Ligament Reconstructed Gait Patterns

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Matthew R. Patterson

2014-01-01

Full Text Available The use of inertial sensors to characterize pathological gait has traditionally been based on the calculation of temporal and spatial gait variables from inertial sensor data. This approach has proved successful in the identification of gait deviations in populations where substantial differences from normal gait patterns exist; such as in Parkinsonian gait. However, it is not currently clear if this approach could identify more subtle gait deviations, such as those associated with musculoskeletal injury. This study investigates whether additional analysis of inertial sensor data, based on quantification of gyroscope features of interest, would provide further discriminant capability in this regard. The tested cohort consisted of a group of anterior cruciate ligament reconstructed (ACL-R females and a group of non-injured female controls, each performed ten walking trials. Gait performance was measured simultaneously using inertial sensors and an optoelectronic marker based system. The ACL-R group displayed kinematic and kinetic deviations from the control group, but no temporal or spatial deviations. This study demonstrates that quantification of gyroscope features can successfully identify changes associated with ACL-R gait, which was not possible using spatial or temporal variables. This finding may also have a role in other clinical applications where small gait deviations exist.

Gait in ducks (Anas platyrhynchos and chickens (Gallus gallus – similarities in adaptation to high growth rate

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B. M. Duggan

2016-08-01

Full Text Available Genetic selection for increased growth rate and muscle mass in broiler chickens has been accompanied by mobility issues and poor gait. There are concerns that the Pekin duck, which is on a similar selection trajectory (for production traits to the broiler chicken, may encounter gait problems in the future. In order to understand how gait has been altered by selection, the walking ability of divergent lines of high- and low-growth chickens and ducks was objectively measured using a pressure platform, which recorded various components of their gait. In both species, lines which had been selected for large breast muscle mass moved at a slower velocity and with a greater step width than their lighter conspecifics. These high-growth lines also spent more time supported by two feet in order to improve balance when compared with their lighter, low-growth conspecifics. We demonstrate that chicken and duck lines which have been subjected to intense selection for high growth rates and meat yields have adapted their gait in similar ways. A greater understanding of which components of gait have been altered in selected lines with impaired walking ability may lead to more effective breeding strategies to improve gait in poultry.

Kinematic and muscle demand similarities between motor-assisted elliptical training and walking: Implications for pediatric gait rehabilitation.

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Burnfield, Judith M; Cesar, Guilherme M; Buster, Thad W; Irons, Sonya L; Nelson, Carl A

2017-01-01

Many children with physical disabilities and special health care needs experience barriers to accessing effective therapeutic technologies to improve walking and fitness in healthcare and community environments. The expense of many robotic and exoskeleton technologies hinders widespread use in most clinics, school settings, and fitness facilities. A motor-assisted elliptical trainer that is being used to address walking and fitness deficits in adults was modified to enable children as young as three years of age to access the technology (Pedi-ICARE). We compared children's kinematic and muscle activation patterns during walking and training on the Pedi-ICARE. Eighteen children walked (self-selected comfortable speed), Pedi-ICARE trained with motor-assistance at self-selected comfortable speed (AAC), and trained while over-riding motor-assistance (AAC+). Coefficient of multiple correlations (CMCs) compared lower extremity kinematic profiles during AAC and AAC+ to gait. Repeated measures ANOVAs identified muscle demand differences across conditions. CMCs revealed strong similarities at the hip and knee between each motor-assisted elliptical condition and gait. Ankle CMCs were only moderate. Muscle demands were generally lowest during AAC. Over-riding the motor increased hip and knee muscle demands. The similarity of motion patterns between Pedi-ICARE conditions and walking suggest the device could be used to promote task-specific training to improve walking. The capacity to manipulate muscle demands using different motor-assistance conditions highlights Pedi-ICARE's versatility in addressing a wide range of children's abilities. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparison of the Classifier Oriented Gait Score and the Gait Profile Score based on imitated gait impairments.

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Christian, Josef; Kröll, Josef; Schwameder, Hermann

2017-06-01

Common summary measures of gait quality such as the Gait Profile Score (GPS) are based on the principle of measuring a distance from the mean pattern of a healthy reference group in a gait pattern vector space. The recently introduced Classifier Oriented Gait Score (COGS) is a pathology specific score that measures this distance in a unique direction, which is indicated by a linear classifier. This approach has potentially improved the discriminatory power to detect subtle changes in gait patterns but does not incorporate a profile of interpretable sub-scores like the GPS. The main aims of this study were to extend the COGS by decomposing it into interpretable sub-scores as realized in the GPS and to compare the discriminative power of the GPS and COGS. Two types of gait impairments were imitated to enable a high level of control of the gait patterns. Imitated impairments were realized by restricting knee extension and inducing leg length discrepancy. The results showed increased discriminatory power of the COGS for differentiating diverse levels of impairment. Comparison of the GPS and COGS sub-scores and their ability to indicate changes in specific variables supports the validity of both scores. The COGS is an overall measure of gait quality with increased power to detect subtle changes in gait patterns and might be well suited for tracing the effect of a therapeutic treatment over time. The newly introduced sub-scores improved the interpretability of the COGS, which is helpful for practical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Biomechanics of normal and pathological gait: implications for understanding human locomotor control.

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Winter, D A

1989-12-01

The biomechanical (kinetic) analysis of human gait reveals the integrated and detailed motor patterns that are essential in pinpointing the abnormal patterns in pathological gait. In a similar manner, these motor patterns (moments, powers, and EMGs) can be used to identify synergies and to validate theories of CNS control. Based on kinetic and EMG patterns for a wide range of normal subjects and cadences, evidence is presented that both supports and negates the central pattern generator theory of locomotion. Adaptive motor patterns that are evident in peripheral gait pathologies reinforce a strong peripheral rather than a central control. Finally, a three-component subtask theory of human gait is presented and is supported by reference to the motor patterns seen in a normal gait. The identified subtasks are (a) support (against collapse during stance); (b) dynamic balance of the upper body, also during stance; and (c) feedforward control of the foot trajectory to achieve safe ground clearance and a gentle heel contact.

Non-surgical management of a pediatric “intoed” gait pattern – a systematic review of the current best evidence

Directory of Open Access Journals (Sweden)

Uden H

2012-01-01

Full Text Available Hayley Uden1, Saravana Kumar21Podiatry Department, University of South Australia, Adelaide, South Australia, Australia; 2Post Doctoral Senior Research Fellow, International Centre for Allied Health Evidence, University of South Australia, Adelaide, South Australia, AustraliaBackground: An intoed gait pattern is one of the most common referrals for children to an orthopedic consultation. Parental concern as to the aesthetics of the child’s gait pattern and/or its symptomatic nature will primarily drive these referrals during a child’s early developmental years. Whilst some of these referrals prove to be the result of a normal growth variant, some children will present with a symptomatic intoed gait pattern. Various treatments, both conservative and surgical, have been proposed including: braces, wedges, stretches and exercises, shoe modifications, and surgical procedures. However, which treatments are effective and justified in the management of this condition is not clear within the literature. The aim of this systematic review was to therefore identify and critique the best available evidence for the non-surgical management of an intoed gait pattern in a pediatric population.Method: A systematic review was conducted of which only experimental studies investigating a management option for an intoeing gait pattern were included. Studies needed to be written in English, pertaining to a human pediatric population, and published within a peer reviewed journal. Electronic databases were searched: Ovid (Medline, EMBASE, AMED, PubMed, SportDiscus, CINAHL, and Cochrane Library. The National Health and Medical Research Council’s designation of levels of hierarchy and the Critical Appraisal Skills Programme cohort studies critical appraisal tool were used.Results: Five level IV studies were found. The studies were of varied quality and with mixed results. Gait plates, physiologic/standardized shoes, and orthotic devices (with gate plate extension

Hardware Development and Locomotion Control Strategy for an Over-Ground Gait Trainer: NaTUre-Gaits.

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Luu, Trieu Phat; Low, Kin Huat; Qu, Xingda; Lim, Hup Boon; Hoon, Kay Hiang

2014-01-01

Therapist-assisted body weight supported (TABWS) gait rehabilitation was introduced two decades ago. The benefit of TABWS in functional recovery of walking in spinal cord injury and stroke patients has been demonstrated and reported. However, shortage of therapists, labor-intensiveness, and short duration of training are some limitations of this approach. To overcome these deficiencies, robotic-assisted gait rehabilitation systems have been suggested. These systems have gained attentions from researchers and clinical practitioner in recent years. To achieve the same objective, an over-ground gait rehabilitation system, NaTUre-gaits, was developed at the Nanyang Technological University. The design was based on a clinical approach to provide four main features, which are pelvic motion, body weight support, over-ground walking experience, and lower limb assistance. These features can be achieved by three main modules of NaTUre-gaits: 1) pelvic assistance mechanism, mobile platform, and robotic orthosis. Predefined gait patterns are required for a robotic assisted system to follow. In this paper, the gait pattern planning for NaTUre-gaits was accomplished by an individual-specific gait pattern prediction model. The model generates gait patterns that resemble natural gait patterns of the targeted subjects. The features of NaTUre-gaits have been demonstrated by walking trials with several subjects. The trials have been evaluated by therapists and doctors. The results show that 10-m walking trial with a reduction in manpower. The task-specific repetitive training approach and natural walking gait patterns were also successfully achieved.

Quantitative Effects of Repeated Muscle Vibrations on Gait Pattern in a 5-Year-Old Child with Cerebral Palsy

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Filippo Camerota

2011-01-01

Full Text Available Objective. To investigate quantitatively and objectively the effects of repeated muscle vibration (rMV of triceps surae on the gait pattern in a 5-year-old patient with Cerebral Palsy with equinus foot deformity due to calf spasticity. Methods. The patient was assessed before and one month after the rMV treatment using Gait Analysis. Results. rMV had positive effects on the patient's gait pattern, as for spatio-temporal parameters (the stance duration and the step length increased their values after the treatment and kinematics. The pelvic tilt reduced its anteversion and the hip reduced the high flexion evidenced at baseline; the knee and the ankle gained a more physiological pattern bilaterally. The Gillette Gait Index showed a significant reduction of its value bilaterally, representing a global improvement of the child's gait pattern. Conclusions. The rMV technique seems to be an effective option for the gait pattern improvement in CP, which can be used also in very young patient. Significant improvements were displayed in terms of kinematics at all lower limb joints, not only at the joint directly involved by the treatment (i.e., ankle and knee joints but also at proximal joints (i.e., pelvis and hip joint.

Gray matter volume covariance patterns associated with gait speed in older adults: a multi-cohort MRI study.

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Blumen, Helena M; Brown, Lucy L; Habeck, Christian; Allali, Gilles; Ayers, Emmeline; Beauchet, Olivier; Callisaya, Michele; Lipton, Richard B; Mathuranath, P S; Phan, Thanh G; Pradeep Kumar, V G; Srikanth, Velandai; Verghese, Joe

2018-04-09

Accelerated gait decline in aging is associated with many adverse outcomes, including an increased risk for falls, cognitive decline, and dementia. Yet, the brain structures associated with gait speed, and how they relate to specific cognitive domains, are not well-understood. We examined structural brain correlates of gait speed, and how they relate to processing speed, executive function, and episodic memory in three non-demented and community-dwelling older adult cohorts (Overall N = 352), using voxel-based morphometry and multivariate covariance-based statistics. In all three cohorts, we identified gray matter volume covariance patterns associated with gait speed that included brain stem, precuneus, fusiform, motor, supplementary motor, and prefrontal (particularly ventrolateral prefrontal) cortex regions. Greater expression of these gray matter volume covariance patterns linked to gait speed were associated with better processing speed in all three cohorts, and with better executive function in one cohort. These gray matter covariance patterns linked to gait speed were not associated with episodic memory in any of the cohorts. These findings suggest that gait speed, processing speed (and to some extent executive functions) rely on shared neural systems that are subject to age-related and dementia-related change. The implications of these findings are discussed within the context of the development of interventions to compensate for age-related gait and cognitive decline.

Newly Identified Gait Patterns in Patients With Multiple Sclerosis May Be Related to Push-off Quality.

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Kempen, Jiska C E; Doorenbosch, Caroline A M; Knol, Dirk L; de Groot, Vincent; Beckerman, Heleen

2016-11-01

Limited walking ability is an important problem for patients with multiple sclerosis. A better understanding of how gait impairments lead to limited walking ability may help to develop more targeted interventions. Although gait classifications are available in cerebral palsy and stroke, relevant knowledge in MS is scarce. The aims of this study were: (1) to identify distinctive gait patterns in patients with MS based on a combined evaluation of kinematics, gait features, and muscle activity during walking and (2) to determine the clinical relevance of these gait patterns. This was a cross-sectional study of 81 patients with MS of mild-to-moderate severity (Expanded Disability Status Scale [EDSS] median score=3.0, range=1.0-7.0) and an age range of 28 to 69 years. The patients participated in 2-dimensional video gait analysis, with concurrent measurement of surface electromyography and ground reaction forces. A score chart of 73 gait items was used to rate each gait analysis. A single rater performed the scoring. Latent class analysis was used to identify gait classes. Analysis of the 73 gait variables revealed that 9 variables could distinguish 3 clinically meaningful gait classes. The 9 variables were: (1) heel-rise in terminal stance, (2) push-off, (3) clearance in initial swing, (4) plantar-flexion position in mid-swing, (5) pelvic rotation, (6) arm-trunk movement, (7) activity of the gastrocnemius muscle in pre-swing, (8) M-wave, and (9) propulsive force. The EDSS score and gait speed worsened in ascending classes. Most participants had mild-to-moderate limitations in walking ability based on their EDSS scores, and the number of walkers who were severely limited was small. Based on a small set of 9 variables measured with 2-dimensional clinical gait analysis, patients with MS could be divided into 3 different gait classes. The gait variables are suggestive of insufficient ankle push-off. © 2016 American Physical Therapy Association.

Changes in gait pattern during multitask using smartphones.

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Jeon, SoYeong; Kim, ChoRong; Song, SunHae; Lee, GyuChang

2015-01-01

With the development of science and technology, smartphones have been deeply involved in people's everyday lives, and many perform various tasks simultaneously on smartphones. To investigate gait pattern changes on performing multitask simultaneously when using smartphones. Three tasks were performed by 26 healthy adults. In the first, participants were directed to walk without using smartphones (single-task). In the second, they were required to walk while finding applications (dual-task). Lastly, in addition to performing the second task, they were asked to listen to questions and answer them on their smartphone (triple-task). Spatiotemporal variables of gait and degree of lateral deviation during walking were measured. The results showed that there was a significant difference between the single-task and dual tasks, as well as between the single task and triple task in all variables (p smartphones in comparison to walking without using smartphones.

Development of an advanced mechanised gait trainer, controlling movement of the centre of mass, for restoring gait in non-ambulant subjects.

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Hesse, S; Sarkodie-Gyan, T; Uhlenbrock, D

1999-01-01

The study aimed at further development of a mechanised gait trainer which would allow non-ambulant people to practice a gait-like motion repeatedly. To simulate normal gait, discrete stance and swing phases, lasting 60% and 40% of the gait cycle respectively, and the control of the movement of the centre of mass were required. A complex gear system provided the gait-like movement of two foot plates with a ratio of 60% to 40% between the stance and swing phases. A controlled propulsion system adjusted its output according to patient's efforts. Two eccenters on the central gear controlled phase-adjusted the vertical and horizontal position of the centre of mass. The patterns of sagittal lower limb joint kinematics and of muscle activation of a normal subject were similar when using the mechanised trainer and when walking on a treadmill. A non-ambulatory hemiparetic subject required little help from one therapist on the gait trainer, while two therapists supported treadmill walking. Gait movements on the trainer were highly symmetrical, impact-free, and less spastic. The weight-bearing muscles were activated in a similar fashion during both conditions. The vertical displacement of the centre of mass was bi-instead of mono-phasic during each gait cycle on the new device. In conclusion, the gait trainer allowed wheelchair-bound subjects the repetitive practice of a gait-like movement without overstraining therapists.

Design of Spiking Central Pattern Generators for Multiple Locomotion Gaits in Hexapod Robots by Christiansen Grammar Evolution.

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Espinal, Andres; Rostro-Gonzalez, Horacio; Carpio, Martin; Guerra-Hernandez, Erick I; Ornelas-Rodriguez, Manuel; Sotelo-Figueroa, Marco

2016-01-01

This paper presents a method to design Spiking Central Pattern Generators (SCPGs) to achieve locomotion at different frequencies on legged robots. It is validated through embedding its designs into a Field-Programmable Gate Array (FPGA) and implemented on a real hexapod robot. The SCPGs are automatically designed by means of a Christiansen Grammar Evolution (CGE)-based methodology. The CGE performs a solution for the configuration (synaptic weights and connections) for each neuron in the SCPG. This is carried out through the indirect representation of candidate solutions that evolve to replicate a specific spike train according to a locomotion pattern (gait) by measuring the similarity between the spike trains and the SPIKE distance to lead the search to a correct configuration. By using this evolutionary approach, several SCPG design specifications can be explicitly added into the SPIKE distance-based fitness function, such as looking for Spiking Neural Networks (SNNs) with minimal connectivity or a Central Pattern Generator (CPG) able to generate different locomotion gaits only by changing the initial input stimuli. The SCPG designs have been successfully implemented on a Spartan 6 FPGA board and a real time validation on a 12 Degrees Of Freedom (DOFs) hexapod robot is presented.

Patterns of mechanical energy change in tetrapod gait: pendula, springs and work.

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Biewener, Andrew A

2006-11-01

Kinematic and center of mass (CoM) mechanical variables used to define terrestrial gaits are compared for various tetrapod species. Kinematic variables (limb phase, duty factor) provide important timing information regarding the neural control and limb coordination of various gaits. Whereas, mechanical variables (potential and kinetic energy relative phase, %Recovery, %Congruity) provide insight into the underlying mechanisms that minimize muscle work and the metabolic cost of locomotion, and also influence neural control strategies. Two basic mechanisms identified by Cavagna et al. (1977. Am J Physiol 233:R243-R261) are used broadly by various bipedal and quadrupedal species. During walking, animals exchange CoM potential energy (PE) with kinetic energy (KE) via an inverted pendulum mechanism to reduce muscle work. During the stance period of running (including trotting, hopping and galloping) gaits, animals convert PE and KE into elastic strain energy in spring elements of the limbs and trunk and regain this energy later during limb support. The bouncing motion of the body on the support limb(s) is well represented by a simple mass-spring system. Limb spring compliance allows the storage and return of elastic energy to reduce muscle work. These two distinct patterns of CoM mechanical energy exchange are fairly well correlated with kinematic distinctions of limb movement patterns associated with gait change. However, in some cases such correlations can be misleading. When running (or trotting) at low speeds many animals lack an aerial period and have limb duty factors that exceed 0.5. Rather than interpreting this as a change of gait, the underlying mechanics of the body's CoM motion indicate no fundamental change in limb movement pattern or CoM dynamics has occurred. Nevertheless, the idealized, distinctive patterns of CoM energy fluctuation predicted by an inverted pendulum for walking and a bouncing mass spring for running are often not clear cut, especially

Intra-individual gait patterns across different time-scales as revealed by means of a supervised learning model using kernel-based discriminant regression.

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Fabian Horst

Full Text Available Traditionally, gait analysis has been centered on the idea of average behavior and normality. On one hand, clinical diagnoses and therapeutic interventions typically assume that average gait patterns remain constant over time. On the other hand, it is well known that all our movements are accompanied by a certain amount of variability, which does not allow us to make two identical steps. The purpose of this study was to examine changes in the intra-individual gait patterns across different time-scales (i.e., tens-of-mins, tens-of-hours.Nine healthy subjects performed 15 gait trials at a self-selected speed on 6 sessions within one day (duration between two subsequent sessions from 10 to 90 mins. For each trial, time-continuous ground reaction forces and lower body joint angles were measured. A supervised learning model using a kernel-based discriminant regression was applied for classifying sessions within individual gait patterns.Discernable characteristics of intra-individual gait patterns could be distinguished between repeated sessions by classification rates of 67.8 ± 8.8% and 86.3 ± 7.9% for the six-session-classification of ground reaction forces and lower body joint angles, respectively. Furthermore, the one-on-one-classification showed that increasing classification rates go along with increasing time durations between two sessions and indicate that changes of gait patterns appear at different time-scales.Discernable characteristics between repeated sessions indicate continuous intrinsic changes in intra-individual gait patterns and suggest a predominant role of deterministic processes in human motor control and learning. Natural changes of gait patterns without any externally induced injury or intervention may reflect continuous adaptations of the motor system over several time-scales. Accordingly, the modelling of walking by means of average gait patterns that are assumed to be near constant over time needs to be reconsidered in the

Intra-individual gait patterns across different time-scales as revealed by means of a supervised learning model using kernel-based discriminant regression.

Science.gov (United States)

Horst, Fabian; Eekhoff, Alexander; Newell, Karl M; Schöllhorn, Wolfgang I

2017-01-01

Traditionally, gait analysis has been centered on the idea of average behavior and normality. On one hand, clinical diagnoses and therapeutic interventions typically assume that average gait patterns remain constant over time. On the other hand, it is well known that all our movements are accompanied by a certain amount of variability, which does not allow us to make two identical steps. The purpose of this study was to examine changes in the intra-individual gait patterns across different time-scales (i.e., tens-of-mins, tens-of-hours). Nine healthy subjects performed 15 gait trials at a self-selected speed on 6 sessions within one day (duration between two subsequent sessions from 10 to 90 mins). For each trial, time-continuous ground reaction forces and lower body joint angles were measured. A supervised learning model using a kernel-based discriminant regression was applied for classifying sessions within individual gait patterns. Discernable characteristics of intra-individual gait patterns could be distinguished between repeated sessions by classification rates of 67.8 ± 8.8% and 86.3 ± 7.9% for the six-session-classification of ground reaction forces and lower body joint angles, respectively. Furthermore, the one-on-one-classification showed that increasing classification rates go along with increasing time durations between two sessions and indicate that changes of gait patterns appear at different time-scales. Discernable characteristics between repeated sessions indicate continuous intrinsic changes in intra-individual gait patterns and suggest a predominant role of deterministic processes in human motor control and learning. Natural changes of gait patterns without any externally induced injury or intervention may reflect continuous adaptations of the motor system over several time-scales. Accordingly, the modelling of walking by means of average gait patterns that are assumed to be near constant over time needs to be reconsidered in the context of

Gait pattern alteration by functional sensory substitution in healthy subjects and in diabetic subjects with peripheral neuropathy.

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Walker, S C; Helm, P A; Lavery, L A

1997-08-01

To evaluate the ability of diabetic and nondiabetic individuals to learn to use a lower extremity sensory substitution device to cue gait pattern changes. Case-control study. Gait laboratory. Thirty diabetic persons and 20 age- and education-matched nondiabetic controls responded to advertisements for study participation. Participants walked on a treadmill at three speeds (1, 2, and 2.5mph) with auditory sensory feedback to cue ground contact greater than 80% duration of baseline. The variables measured included gait cycle (steps per minute) and number of times per minute that any step during a trial exceeded 80% duration of ground contacted compared with a measured baseline step length for each speed. Persons in both groups were able to rapidly and significantly alter their gait patterns in response to signals from the sensory substitution device, by changing their gait cycles (nondiabetic group, F(17,124) = 5.27, p gait cycle modification and error reduction among both groups. The nondiabetic group learned to use the device significantly more quickly than the diabetic group during the slow (1mph, t = 3.57, p gait trainer malfunction occurred during the study. Diabetic persons with neuropathy effectively used lower extremity sensory substitution, and the technology is now available to manufacture a durable, effective lower extremity sensory substitution system.

Technical note: Use of accelerometers to describe gait patterns in dairy calves

DEFF Research Database (Denmark)

Passillé, A. M. de; Jensen, Margit Bak; Chapinal, N.

2010-01-01

Developments in accelerometer technology offer new opportunities for automatic monitoring of animal behavior. Until now, commercially available accelerometers have been used to measure walking in adult cows but have failed to identify walking in calves. We described the pattern of acceleration...... associated with various gaits in calves and tested whether measures of acceleration could be used to count steps and distinguish among gait types. A triaxial accelerometer (sampling at 33 readings/s with maximum measurement at +/-3.2 g) was attached to 1 hind leg of 7 dairy calves, and each calf was walked...

Identification of Characteristic Motor Patterns Preceding Freezing of Gait in Parkinson’s Disease Using Wearable Sensors

Directory of Open Access Journals (Sweden)

Luca Palmerini

2017-08-01

Full Text Available Freezing of gait (FOG is a disabling symptom that is common among patients with advanced Parkinson’s disease (PD. External cues such as rhythmic auditory stimulation can help PD patients experiencing freezing to resume walking. Wearable systems for automatic freezing detection have been recently developed. However, these systems detect a FOG episode after it has happened. Instead, in this study, a new approach for the prediction of FOG (before it actually happens is presented. Prediction of FOG might enable preventive cueing, reducing the likelihood that FOG will occur. Moreover, understanding the causes and circumstances of FOG is still an open research problem. Hence, a quantitative characterization of movement patterns just before FOG (the pre-FOG phase is of great importance. In this study, wearable inertial sensors were used to identify and quantify the characteristics of gait during the pre-FOG phase and compare them with the characteristics of gait that do not precede FOG. The hypothesis of this study is based on the threshold-based model of FOG, which suggests that before FOG occurs, there is a degradation of the gait pattern. Eleven PD subjects were analyzed. Six features extracted from movement signals recorded by inertial sensors showed significant differences between gait and pre-FOG. A classification algorithm was developed in order to test if it is feasible to predict FOG (i.e., detect it before it happens. The aim of the classification procedure was to identify the pre-FOG phase. Results confirm that there is a degradation of gait occurring before freezing. Results also provide preliminary evidence on the feasibility of creating an automatic algorithm to predict FOG. Although some limitations are present, this study shows promising findings for characterizing and identifying pre-FOG patterns, another step toward a better understanding, prediction, and prevention of this disabling symptom.

Variability and Similarity of Gait as Evaluated by Joint Angles

DEFF Research Database (Denmark)

Yang, Sylvia X M; Larsen, Peter Kastmand; Alkjær, Tine

2014-01-01

. Six sets from 12 men were collected. For each man, a variability range VR (mean ± 1SD) of a specific joint angle at a specific time point (a gait cycle was 100 time points) was calculated. In turn, each individual was compared with the 11 others, and whenever 1 of these 11 had a value within...... this individual’s VR, it counted as positive. By adding the positives throughout the gait cycle, we created simple bar graphs; tall bars indicated a small discriminatory power, short bars indicated a larger one. The highest discriminatory power was at time points 60–80 in the gait cycle. We show how our data can...

Learning new gait patterns: Exploratory muscle activity during motor learning is not predicted by motor modules

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Ranganathan, Rajiv; Krishnan, Chandramouli; Dhaher, Yasin Y.; Rymer, William Z.

2018-01-01

The motor module hypothesis in motor control proposes that the nervous system can simplify the problem of controlling a large number of muscles in human movement by grouping muscles into a smaller number of modules. Here, we tested one prediction of the modular organization hypothesis by examining whether there is preferential exploration along these motor modules during the learning of a new gait pattern. Healthy college-aged participants learned a new gait pattern which required increased hip and knee flexion during the swing phase while walking in a lower-extremity robot (Lokomat). The new gait pattern was displayed as a foot trajectory in the sagittal plane and participants attempted to match their foot trajectory to this template. We recorded EMG from 8 lower-extremity muscles and we extracted motor modules during both baseline walking and target-tracking using non-negative matrix factorization (NMF). Results showed increased trajectory variability in the first block of learning, indicating that participants were engaged in exploratory behavior. Critically, when we examined the muscle activity during this exploratory phase, we found that the composition of motor modules changed significantly within the first few strides of attempting the new gait pattern. The lack of persistence of the motor modules under even short time scales suggests that motor modules extracted during locomotion may be more indicative of correlated muscle activity induced by the task constraints of walking, rather than reflecting a modular control strategy. PMID:26916510

Adaptive Strategy for Online Gait Learning Evaluated on the Polymorphic Robotic LocoKit

DEFF Research Database (Denmark)

Christensen, David Johan; Larsen, Jørgen Christian; Stoy, Kasper

2012-01-01

This paper presents experiments with a morphologyindependent, life-long strategy for online learning of locomotion gaits, performed on a quadruped robot constructed from the LocoKit modular robot. The learning strategy applies a stochastic optimization algorithm to optimize eight open parameters...... of a central pattern generator based gait implementation. We observe that the strategy converges in roughly ten minutes to gaits of similar or higher velocity than a manually designed gait and that the strategy readapts in the event of failed actuators. In future work we plan to study co-learning...

Examination of the gait pattern based on adjusting and resulting components of the stride-to-stride variability

DEFF Research Database (Denmark)

Laessoe, Uffe; Jensen, Niels Martin Brix; Madeleine, Pascal

2017-01-01

Stride-to-stride variability may be used as an indicator in the assessment of gait performance, but the evaluation of this parameter is not trivial. In the gait pattern, a deviation in one stride must be corrected within the next strides (elemental variables) to ensure a steady gait (performance .......5 to 2 strides with 0.5 stride increments. The time lag values corresponded to the following contralateral stride, the following ipsilateral stride, the second following contralateral stride and the second following ipsilateral stride....

Assistive devices alter gait patterns in Parkinson disease: advantages of the four-wheeled walker.

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Kegelmeyer, Deb A; Parthasarathy, Sowmya; Kostyk, Sandra K; White, Susan E; Kloos, Anne D

2013-05-01

Gait abnormalities are a hallmark of Parkinson's disease (PD) and contribute to fall risk. Therapy and exercise are often encouraged to increase mobility and decrease falls. As disease symptoms progress, assistive devices are often prescribed. There are no guidelines for choosing appropriate ambulatory devices. This unique study systematically examined the impact of a broad range of assistive devices on gait measures during walking in both a straight path and around obstacles in individuals with PD. Quantitative gait measures, including velocity, stride length, percent swing and double support time, and coefficients of variation were assessed in 27 individuals with PD with or without one of six different devices including canes, standard and wheeled walkers (two, four or U-Step). Data were collected using the GAITRite and on a figure-of-eight course. All devices, with the exception of four-wheeled and U-Step walkers significantly decreased gait velocity. The four-wheeled walker resulted in less variability in gait measures and had less impact on spontaneous unassisted gait patterns. The U-Step walker exhibited the highest variability across all parameters followed by the two-wheeled and standard walkers. Higher variability has been correlated with increased falls. Though subjects performed better on a figure-of-eight course using either the four-wheeled or the U-Step walker, the four-wheeled walker resulted in the most consistent improvement in overall gait variables. Laser light use on a U-Step walker did not improve gait measures or safety in figure-of-eight compared to other devices. Of the devices tested, the four-wheeled-walker offered the most consistent advantages for improving mobility and safety. Copyright © 2012 Elsevier B.V. All rights reserved.

Characteristics of daily life gait in fall and non fall-prone stroke survivors and controls

NARCIS (Netherlands)

Mirjam Pijnappels; Sjoerd M. Bruijn; Kimberley M. Schooten; Jaap H. van Dieën; Dr. H.M. Wittink; Michiel Punt

2016-01-01

Background: Falls in stroke survivors can lead to serious injuries and medical costs. Fall risk in older adults can be predicted based on gait characteristics measured in daily life. Given the different gait patterns that stroke survivors exhibit it is unclear whether a similar fall-prediction model

Neuromorphic walking gait control.

Science.gov (United States)

Still, Susanne; Hepp, Klaus; Douglas, Rodney J

2006-03-01

We present a neuromorphic pattern generator for controlling the walking gaits of four-legged robots which is inspired by central pattern generators found in the nervous system and which is implemented as a very large scale integrated (VLSI) chip. The chip contains oscillator circuits that mimic the output of motor neurons in a strongly simplified way. We show that four coupled oscillators can produce rhythmic patterns with phase relationships that are appropriate to generate all four-legged animal walking gaits. These phase relationships together with frequency and duty cycle of the oscillators determine the walking behavior of a robot driven by the chip, and they depend on a small set of stationary bias voltages. We give analytic expressions for these dependencies. This chip reduces the complex, dynamic inter-leg control problem associated with walking gait generation to the problem of setting a few stationary parameters. It provides a compact and low power solution for walking gait control in robots.

Post-stroke hemiparesis: Does chronicity, etiology, and lesion side are associated with gait pattern?

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Gama, Gabriela Lopes; Larissa, Coutinho de Lucena; Brasileiro, Ana Carolina de Azevedo Lima; Silva, Emília Márcia Gomes de Souza; Galvão, Élida Rayanne Viana Pinheiro; Maciel, Álvaro Cavalcanti; Lindquist, Ana Raquel Rodrigues

2017-07-01

Studies that evaluate gait rehabilitation programs for individuals with stroke often consider time since stroke of more than six months. In addition, most of these studies do not use lesion etiology or affected cerebral hemisphere as study factors. However, it is unknown whether these factors are associated with post-stroke motor performance after the spontaneous recovery period. To investigate whether time since stroke onset, etiology, and lesion side is associated with spatiotemporal and angular gait parameters of individuals with chronic stroke. Fifty individuals with chronic hemiparesis (20 women) were evaluated. The sample was stratified according to time since stroke (between 6 and 12 months, between 13 and 36 months, and over 36 months), affected cerebral hemisphere (left or right) and lesion etiology (ischemic and hemorrhagic). The participants were evaluated during overground walking at self-selected gait speed, and spatiotemporal and angular gait parameters were calculated. Results Differences between gait speed, stride length, hip flexion, and knee flexion were observed in subgroups stratified based on lesion etiology. Survivors of a hemorrhagic stroke exhibited more severe gait impairment. Subgroups stratified based on time since stroke only showed intergroup differences for stride length, and subgroups stratified based on affected cerebral hemisphere displayed between-group differences for swing time symmetry ratio. In order to recruit a more homogeneous sample, more accurate results were obtained and an appropriate rehabilitation program was offered, researchers and clinicians should consider that gait pattern might be associated with time since stroke, affected cerebral hemisphere and lesion etiology.

Effects of Indoor Footwear on Balance and Gait Patterns in Community-Dwelling Older Women.

Science.gov (United States)

Menz, Hylton B; Auhl, Maria; Munteanu, Shannon E

2017-01-01

Footwear worn indoors is generally less supportive than outdoor footwear and may increase the risk of falls. To evaluate balance ability and gait patterns in older women while wearing different styles of indoor footwear: a backless slipper and an enclosed slipper designed to optimise balance. Older women (n = 30) aged 65-83 years (mean 74.4, SD 5.6) performed a series of laboratory tests of balance ability (postural sway, limits of stability, and tandem walking, measured with the NeuroCom® Balance Master) and gait patterns (walking speed, cadence, and step length, measured with the GAITRite® walkway) while wearing (1) socks, (2) backless slippers with a soft sole, and (3) enclosed slippers with a firm sole and Velcro® fastening. Perceptions of the footwear were also documented using a structured questionnaire. Significant overall effects of footwear were observed for postural sway, the limits of stability test (directional control), the tandem walk test (step width and end sway), and temporospatial gait patterns (walking speed, cadence, and step length). No footwear effects were observed for maximum excursion when performing the limits of stability test or for speed when performing the tandem walk test. Post hoc tests indicated that performances were best while wearing the enclosed slippers, intermediate with socks, and worst with backless slippers. The enclosed slippers were perceived to be more attractive, comfortable, and well fitted, but heavier than the backless slippers. Most participants (n = 23; 77%) reported that they would consider wearing the enclosed slippers to reduce their risk of falling. Indoor footwear with an enclosed heel, Velcro® fastening, and a firm sole optimises balance and gait compared to backless slippers, and is therefore recommended to reduce the risk of falling. © 2016 The Author(s) Published by S. Karger AG, Basel.

Children with Spastic Cerebral Palsy Experience Difficulties Adjusting Their Gait Pattern to Weight Added to the Waist, While Typically Developing Children Do Not

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Meyns, Pieter; Van Gestel, Leen; Bar-On, Lynn; Goudriaan, Marije; Wambacq, Hans; Aertbeliën, Erwin; Bruyninckx, Herman; Molenaers, Guy; De Cock, Paul; Ortibus, Els; Desloovere, Kaat

2016-01-01

The prevalence of childhood overweight and obesity is increasing in the last decades, also in children with Cerebral Palsy (CP). Even though it has been established that an increase in weight can have important negative effects on gait in healthy adults and children, it has not been investigated what the effect is of an increase in body weight on the characteristics of gait in children with CP. In CP, pre and post three-dimensional gait analyses are performed to assess the effectiveness of an intervention. As a considerable amount of time can elapse between these measurements, and the effect of an alteration in the body weight is not taken into consideration, this effect of increased body weight is of specific importance. Thirty children with the predominantly spastic type of CP and 15 typically developing (TD) children were enrolled (age 3–15 years). All children underwent three-dimensional gait analysis with weight-free (baseline) and weighted (10% of the body weight added around their waist) trials. Numerous gait parameters showed a different response to the added weight for TD and CP children. TD children increased walking velocity, step- and stride length, and decreased double support duration with a slightly earlier timing of foot-off, while the opposite was found in CP. Similarly, increased ranges of motion at the pelvis (coronal plane) and hip (all planes), higher joint angular velocities at the hip and ankle, as well as increased moments and powers at the hip, knee and ankle were observed for TD children, while CP children did not change or even showed decreases in the respective measures in response to walking with added weight. Further, while TD children increased their gastrocnemius EMG amplitude during weighted walking, CP children slightly decreased their gastrocnemius EMG amplitude. As such, an increase in weight has a significant effect on the gait pattern in CP children. Clinical gait analysts should therefore take into account the negative

Quantifying stimulus-response rehabilitation protocols by auditory feedback in Parkinson's disease gait pattern

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Pineda, Gustavo; Atehortúa, Angélica; Iregui, Marcela; García-Arteaga, Juan D.; Romero, Eduardo

2017-11-01

External auditory cues stimulate motor related areas of the brain, activating motor ways parallel to the basal ganglia circuits and providing a temporary pattern for gait. In effect, patients may re-learn motor skills mediated by compensatory neuroplasticity mechanisms. However, long term functional gains are dependent on the nature of the pathology, follow-up is usually limited and reinforcement by healthcare professionals is crucial. Aiming to cope with these challenges, several researches and device implementations provide auditory or visual stimulation to improve Parkinsonian gait pattern, inside and outside clinical scenarios. The current work presents a semiautomated strategy for spatio-temporal feature extraction to study the relations between auditory temporal stimulation and spatiotemporal gait response. A protocol for auditory stimulation was built to evaluate the integrability of the strategy in the clinic practice. The method was evaluated in transversal measurement with an exploratory group of people with Parkinson's (n = 12 in stage 1, 2 and 3) and control subjects (n =6). The result showed a strong linear relation between auditory stimulation and cadence response in control subjects (R=0.98 +/-0.008) and PD subject in stage 2 (R=0.95 +/-0.03) and stage 3 (R=0.89 +/-0.05). Normalized step length showed a variable response between low and high gait velocity (0.2> R >0.97). The correlation between normalized mean velocity and stimulus was strong in all PD stage 2 (R>0.96) PD stage 3 (R>0.84) and controls (R>0.91) for all experimental conditions. Among participants, the largest variation from baseline was found in PD subject in stage 3 (53.61 +/-39.2 step/min, 0.12 +/- 0.06 in step length and 0.33 +/- 0.16 in mean velocity). In this group these values were higher than the own baseline. These variations are related with direct effect of metronome frequency on cadence and velocity. The variation of step length involves different regulation strategies and

A biofeedback cycling training to improve locomotion: a case series study based on gait pattern classification of 153 chronic stroke patients

Science.gov (United States)

2011-01-01

Background The restoration of walking ability is the main goal of post-stroke lower limb rehabilitation and different studies suggest that pedaling may have a positive effect on locomotion. The aim of this study was to explore the feasibility of a biofeedback pedaling treatment and its effects on cycling and walking ability in chronic stroke patients. A case series study was designed and participants were recruited based on a gait pattern classification of a population of 153 chronic stroke patients. Methods In order to optimize participants selection, a k-means cluster analysis was performed to subgroup homogenous gait patterns in terms of gait speed and symmetry. The training consisted of a 2-week treatment of 6 sessions. A visual biofeedback helped the subjects in maintaining a symmetrical contribution of the two legs during pedaling. Participants were assessed before, after training and at follow-up visits (one week after treatment). Outcome measures were the unbalance during a pedaling test, and the temporal, spatial, and symmetry parameters during gait analysis. Results and discussion Three clusters, mainly differing in terms of gait speed, were identified and participants, representative of each cluster, were selected. An intra-subject statistical analysis (ANOVA) showed that all patients significantly decreased the pedaling unbalance after treatment and maintained significant improvements with respect to baseline at follow-up. The 2-week treatment induced some modifications in the gait pattern of two patients: one, the most impaired, significantly improved mean velocity and increased gait symmetry; the other one reduced significantly the over-compensation of the healthy limb. No benefits were produced in the gait of the last subject who maintained her slow but almost symmetrical pattern. Thus, this study might suggest that the treatment can be beneficial for patients having a very asymmetrical and inefficient gait and for those that overuse the healthy leg

A biofeedback cycling training to improve locomotion: a case series study based on gait pattern classification of 153 chronic stroke patients

Directory of Open Access Journals (Sweden)

Molteni Franco

2011-08-01

Full Text Available Abstract Background The restoration of walking ability is the main goal of post-stroke lower limb rehabilitation and different studies suggest that pedaling may have a positive effect on locomotion. The aim of this study was to explore the feasibility of a biofeedback pedaling treatment and its effects on cycling and walking ability in chronic stroke patients. A case series study was designed and participants were recruited based on a gait pattern classification of a population of 153 chronic stroke patients. Methods In order to optimize participants selection, a k-means cluster analysis was performed to subgroup homogenous gait patterns in terms of gait speed and symmetry. The training consisted of a 2-week treatment of 6 sessions. A visual biofeedback helped the subjects in maintaining a symmetrical contribution of the two legs during pedaling. Participants were assessed before, after training and at follow-up visits (one week after treatment. Outcome measures were the unbalance during a pedaling test, and the temporal, spatial, and symmetry parameters during gait analysis. Results and discussion Three clusters, mainly differing in terms of gait speed, were identified and participants, representative of each cluster, were selected. An intra-subject statistical analysis (ANOVA showed that all patients significantly decreased the pedaling unbalance after treatment and maintained significant improvements with respect to baseline at follow-up. The 2-week treatment induced some modifications in the gait pattern of two patients: one, the most impaired, significantly improved mean velocity and increased gait symmetry; the other one reduced significantly the over-compensation of the healthy limb. No benefits were produced in the gait of the last subject who maintained her slow but almost symmetrical pattern. Thus, this study might suggest that the treatment can be beneficial for patients having a very asymmetrical and inefficient gait and for those

Lumbar kinematic variability during gait in chronic low back pain and associations with pain, disability and isolated lumbar extension strength.

Science.gov (United States)

Steele, James; Bruce-Low, Stewart; Smith, Dave; Jessop, David; Osborne, Neil

2014-12-01

Chronic low back pain is a multifactorial condition with many dysfunctions including gait variability. The lumbar spine and its musculature are involved during gait and in chronic low back pain the lumbar extensors are often deconditioned. It was therefore of interest to examine relationships between lumbar kinematic variability during gait, with pain, disability and isolated lumbar extension strength in participants with chronic low back pain. Twenty four participants with chronic low back pain were assessed for lumbar kinematics during gait, isolated lumbar extension strength, pain, and disability. Angular displacement and kinematic waveform pattern and offset variability were examined. Angular displacement and kinematic waveform pattern and offset variability differed across movement planes; displacement was highest and similar in frontal and transverse planes, and pattern variability and offset variability higher in the sagittal plane compared to frontal and transverse planes which were similar. Spearman's correlations showed significant correlations between transverse plane pattern variability and isolated lumbar extension strength (r=-.411) and disability (r=.401). However, pain was not correlated with pattern variability in any plane. The r(2) values suggested 80.5% to 86.3% of variance was accounted for by other variables. Considering the lumbar extensors role in gait, the relationship between both isolated lumbar extension strength and disability with transverse plane pattern variability suggests that gait variability may result in consequence of lumbar extensor deconditioning or disability accompanying chronic low back pain. However, further study should examine the temporality of these relationships and other variables might account for the unexplained variance. Copyright © 2014 Elsevier Ltd. All rights reserved.

Why is walker-assisted gait metabolically expensive?

Science.gov (United States)

Priebe, Jonathon R; Kram, Rodger

2011-06-01

Walker-assisted gait is reported to be ∼200% more metabolically expensive than normal bipedal walking. However, previous studies compared different walking speeds. Here, we compared the metabolic power consumption and basic stride temporal-spatial parameters for 10 young, healthy adults walking without assistance and using 2-wheeled (2W), 4-wheeled (4W) and 4-footed (4F) walker devices, all at the same speed, 0.30m/s. We also measured the metabolic power demand for walking without any assistive device using a step-to gait at 0.30m/s, walking normally at 1.25m/s, and for repeated lifting of the 4F walker mimicking the lifting pattern used during 4F walker-assisted gait. Similar to previous studies, we found that the cost per distance walked was 217% greater with a 4F walker at 0.30m/s compared to unassisted, bipedal walking at 1.25m/s. Compared at the same speed, 0.30m/s, using a 4F walker was still 82%, 74%, and 55% energetically more expensive than walking unassisted, with a 4W walker and a 2W walker respectively. The sum of the metabolic cost of step-to walking plus the cost of lifting itself was equivalent to the cost of walking with a 4F walker. Thus, we deduce that the high cost of 4F walker assisted gait is due to three factors: the slow walking speed, the step-to gait pattern and the repeated lifting of the walker. Copyright © 2011 Elsevier B.V. All rights reserved.

Stepping strategies for regulating gait adaptability and stability.

Science.gov (United States)

Hak, Laura; Houdijk, Han; Steenbrink, Frans; Mert, Agali; van der Wurff, Peter; Beek, Peter J; van Dieën, Jaap H

2013-03-15

Besides a stable gait pattern, gait in daily life requires the capability to adapt this pattern in response to environmental conditions. The purpose of this study was to elucidate the anticipatory strategies used by able-bodied people to attain an adaptive gait pattern, and how these strategies interact with strategies used to maintain gait stability. Ten healthy subjects walked in a Computer Assisted Rehabilitation ENvironment (CAREN). To provoke an adaptive gait pattern, subjects had to hit virtual targets, with markers guided by their knees, while walking on a self-paced treadmill. The effects of walking with and without this task on walking speed, step length, step frequency, step width and the margins of stability (MoS) were assessed. Furthermore, these trials were performed with and without additional continuous ML platform translations. When an adaptive gait pattern was required, subjects decreased step length (padaptations resulted in the preservation of equal MoS between trials, despite the disturbing influence of the gait adaptability task. When the gait adaptability task was combined with the balance perturbation subjects further decreased step length, as evidenced by a significant interaction between both manipulations (p=0.012). In conclusion, able-bodied people reduce step length and increase step width during walking conditions requiring a high level of both stability and adaptability. Although an increase in step frequency has previously been found to enhance stability, a faster movement, which would coincide with a higher step frequency, hampers accuracy and may consequently limit gait adaptability. Copyright © 2012 Elsevier Ltd. All rights reserved.

The impact of Nordic walking training on the gait of the elderly.

Science.gov (United States)

Ben Mansour, Khaireddine; Gorce, Philippe; Rezzoug, Nasser

2018-03-27

The purpose of the current study was to define the impact of regular practice of Nordic walking on the gait of the elderly. Thereby, we aimed to determine whether the gait characteristics of active elderly persons practicing Nordic walking are more similar to healthy adults than that of the sedentary elderly. Comparison was made based on parameters computed from three inertial sensors during walking at a freely chosen velocity. Results showed differences in gait pattern in terms of the amplitude computed from acceleration and angular velocity at the lumbar region (root mean square), the distribution (Skewness) quantified from the vertical and Euclidean norm of the lumbar acceleration, the complexity (Sample Entropy) of the mediolateral component of lumbar angular velocity and the Euclidean norm of the shank acceleration and angular velocity, the regularity of the lower limbs, the spatiotemporal parameters and the variability (standard deviation) of stance and stride durations. These findings reveal that the pattern of active elderly differs significantly from sedentary elderly of the same age while similarity was observed between the active elderly and healthy adults. These results advance that regular physical activity such as Nordic walking may counteract the deterioration of gait quality that occurs with aging.

DMRT3 is associated with gait type in Mangalarga Marchador horses, but does not control gait ability.

Science.gov (United States)

Patterson, L; Staiger, E A; Brooks, S A

2015-04-01

The Mangalarga Marchador (MM) is a Brazilian horse breed known for a uniquely smooth gait. A recent publication described a mutation in the DMRT3 gene that the authors claim controls the ability to perform lateral patterned gaits (Andersson et al. 2012). We tested 81 MM samples for the DMRT3 mutation using extracted DNA from hair bulbs using a novel RFLP. Horses were phenotypically categorized by their gait type (batida or picada), as recorded by the Brazilian Mangalarga Marchador Breeders Association (ABCCMM). Statistical analysis using the plink toolset (Purcell, 2007) revealed significant association between gait type and the DMRT3 mutation (P = 2.3e-22). Deviation from Hardy-Weinberg equilibrium suggests that selective pressure for gait type is altering allele frequencies in this breed (P = 1.00e-5). These results indicate that this polymorphism may be useful for genotype-assisted selection for gait type within this breed. As both batida and picada MM horses can perform lateral gaits, the DMRT3 mutation is not the only locus responsible for the lateral gait pattern. © 2015 Stichting International Foundation for Animal Genetics.

Wearable Device-Based Gait Recognition Using Angle Embedded Gait Dynamic Images and a Convolutional Neural Network.

Science.gov (United States)

Zhao, Yongjia; Zhou, Suiping

2017-02-28

The widespread installation of inertial sensors in smartphones and other wearable devices provides a valuable opportunity to identify people by analyzing their gait patterns, for either cooperative or non-cooperative circumstances. However, it is still a challenging task to reliably extract discriminative features for gait recognition with noisy and complex data sequences collected from casually worn wearable devices like smartphones. To cope with this problem, we propose a novel image-based gait recognition approach using the Convolutional Neural Network (CNN) without the need to manually extract discriminative features. The CNN's input image, which is encoded straightforwardly from the inertial sensor data sequences, is called Angle Embedded Gait Dynamic Image (AE-GDI). AE-GDI is a new two-dimensional representation of gait dynamics, which is invariant to rotation and translation. The performance of the proposed approach in gait authentication and gait labeling is evaluated using two datasets: (1) the McGill University dataset, which is collected under realistic conditions; and (2) the Osaka University dataset with the largest number of subjects. Experimental results show that the proposed approach achieves competitive recognition accuracy over existing approaches and provides an effective parametric solution for identification among a large number of subjects by gait patterns.

Wearable Device-Based Gait Recognition Using Angle Embedded Gait Dynamic Images and a Convolutional Neural Network

Science.gov (United States)

Zhao, Yongjia; Zhou, Suiping

2017-01-01

The widespread installation of inertial sensors in smartphones and other wearable devices provides a valuable opportunity to identify people by analyzing their gait patterns, for either cooperative or non-cooperative circumstances. However, it is still a challenging task to reliably extract discriminative features for gait recognition with noisy and complex data sequences collected from casually worn wearable devices like smartphones. To cope with this problem, we propose a novel image-based gait recognition approach using the Convolutional Neural Network (CNN) without the need to manually extract discriminative features. The CNN’s input image, which is encoded straightforwardly from the inertial sensor data sequences, is called Angle Embedded Gait Dynamic Image (AE-GDI). AE-GDI is a new two-dimensional representation of gait dynamics, which is invariant to rotation and translation. The performance of the proposed approach in gait authentication and gait labeling is evaluated using two datasets: (1) the McGill University dataset, which is collected under realistic conditions; and (2) the Osaka University dataset with the largest number of subjects. Experimental results show that the proposed approach achieves competitive recognition accuracy over existing approaches and provides an effective parametric solution for identification among a large number of subjects by gait patterns. PMID:28264503

Differential effects of rhythmic auditory stimulation and neurodevelopmental treatment/Bobath on gait patterns in adults with cerebral palsy: a randomized controlled trial.

Science.gov (United States)

Kim, Soo Ji; Kwak, Eunmi E; Park, Eun Sook; Cho, Sung-Rae

2012-10-01

To investigate the effects of rhythmic auditory stimulation (RAS) on gait patterns in comparison with changes after neurodevelopmental treatment (NDT/Bobath) in adults with cerebral palsy. A repeated-measures analysis between the pretreatment and posttreatment tests and a comparison study between groups. Human gait analysis laboratory. Twenty-eight cerebral palsy patients with bilateral spasticity participated in this study. The subjects were randomly allocated to either neurodevelopmental treatment (n = 13) or rhythmic auditory stimulation (n = 15). Gait training with rhythmic auditory stimulation or neurodevelopmental treatment was performed three sessions per week for three weeks. Temporal and kinematic data were analysed before and after the intervention. Rhythmic auditory stimulation was provided using a combination of a metronome beat set to the individual's cadence and rhythmic cueing from a live keyboard, while neurodevelopmental treatment was implemented following the traditional method. Temporal data, kinematic parameters and gait deviation index as a measure of overall gait pathology were assessed. Temporal gait measures revealed that rhythmic auditory stimulation significantly increased cadence, walking velocity, stride length, and step length (P rhythmic auditory stimulation (P rhythmic auditory stimulation (P rhythmic auditory stimulation showed aggravated maximal internal rotation in the transverse plane (P rhythmic auditory stimulation or neurodevelopmental treatment elicited differential effects on gait patterns in adults with cerebral palsy.

Changes in gait patterns induced by rhythmic auditory stimulation for adolescents with acquired brain injury.

Science.gov (United States)

Kim, Soo Ji; Shin, Yoon-Kyum; Yoo, Ga Eul; Chong, Hyun Ju; Cho, Sung-Rae

2016-12-01

The effects of rhythmic auditory stimulation (RAS) on gait in adolescents with acquired brain injury (ABI) were investigated. A total of 14 adolescents with ABI were initially recruited, and 12 were included in the final analysis (n = 6 each). They were randomly assigned to the experimental (RAS) or the control (conventional gait training) groups. The experimental group received gait training with RAS three times a week for 4 weeks. For both groups, spatiotemporal parameters and kinematic data, such as dynamic motions of joints on three-dimensional planes during a gait cycle and the range of motion in each joint, were collected. Significant group differences in pre-post changes were observed in cadence, walking velocity, and step time, indicating that there were greater improvements in those parameters in the RAS group compared with the control group. Significant increases in hip and knee motions in the sagittal plane were also observed in the RAS group. The changes in kinematic data significantly differed between groups, particularly from terminal stance to mid-swing phase. An increase of both spatiotemporal parameters and corresponding kinematic changes of hip and knee joints after RAS protocol indicates that the use of rhythmic cueing may change gait patterns in adolescents with ABI. © 2016 The Authors. Annals of the New York Academy of Sciences published by Wiley Periodicals, Inc. on behalf of New York Academy of Sciences.

A structural equation model relating impaired sensorimotor function, fear of falling and gait patterns in older people.

Science.gov (United States)

Menz, Hylton B; Lord, Stephen R; Fitzpatrick, Richard C

2007-02-01

Many falls in older people occur while walking, however the mechanisms responsible for gait instability are poorly understood. Therefore, the aim of this study was to develop a plausible model describing the relationships between impaired sensorimotor function, fear of falling and gait patterns in older people. Temporo-spatial gait parameters and acceleration patterns of the head and pelvis were obtained from 100 community-dwelling older people aged between 75 and 93 years while walking on an irregular walkway. A theoretical model was developed to explain the relationships between these variables, assuming that head stability is a primary output of the postural control system when walking. This model was then tested using structural equation modeling, a statistical technique which enables the testing of a set of regression equations simultaneously. The structural equation model indicated that: (i) reduced step length has a significant direct and indirect association with reduced head stability; (ii) impaired sensorimotor function is significantly associated with reduced head stability, but this effect is largely indirect, mediated by reduced step length, and; (iii) fear of falling is significantly associated with reduced step length, but has little direct influence on head stability. These findings provide useful insights into the possible mechanisms underlying gait characteristics and risk of falling in older people. Particularly important is the indication that fear-related step length shortening may be maladaptive.

The influence of applying additional weight to the affected leg on gait patterns during aquatic treadmill walking in people poststroke.

Science.gov (United States)

Jung, Taeyou; Lee, Dokyeong; Charalambous, Charalambos; Vrongistinos, Konstantinos

2010-01-01

Jung T, Lee D, Charalambous C, Vrongistinos K. The influence of applying additional weight to the affected leg on gait patterns during aquatic treadmill walking in people poststroke. To investigate how the application of additional weights to the affected leg influences gait patterns of people poststroke during aquatic treadmill walking. Comparative gait analysis. University-based aquatic therapy center. Community-dwelling volunteers (n=22) with chronic hemiparesis caused by stroke. Not applicable. Spatiotemporal and kinematic gait parameters. The use of an ankle weight showed an increase in the stance phase percentage of gait cycle (3%, P=.015) when compared with no weight. However, the difference was not significant after a Bonferroni adjustment was applied for a more stringent statistical analysis. No significant differences were found in cadence and stride length. The use of an ankle weight showed a significant decrease of the peak hip flexion (7.9%, P=.001) of the affected limb as compared with no weight condition. This decrease was marked as the reduction of unwanted limb flotation because people poststroke typically show excessive hip flexion of the paretic leg in the late swing phase followed by fluctuating hip movements during aquatic treadmill walking. The frontal and transverse plane hip motions did not show any significant differences but displayed a trend of a decrease in the peak hip abduction during the swing phase with additional weights. The use of additional weight did not alter sagittal plane kinematics of the knee and ankle joints. The use of applied weight on the affected limb can reduce unwanted limb flotation on the paretic side during aquatic treadmill walking. It can also assist the stance stability by increasing the stance phase percentage closer to 60% of gait cycle. Both findings can contribute to the development of more efficient motor patterns in gait training for people poststroke. The use of a cuff weight does not seem to reduce the

How innate is locomotion in precocial animals? A study on the early development of spatio-temporal gait variables and gait symmetry in piglets.

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Vanden Hole, Charlotte; Goyens, Jana; Prims, Sara; Fransen, Erik; Ayuso Hernando, Miriam; Van Cruchten, Steven; Aerts, Peter; Van Ginneken, Chris

2017-08-01

Locomotion is one of the most important ecological functions in animals. Precocial animals, such as pigs, are capable of independent locomotion shortly after birth. This raises the question whether coordinated movement patterns and the underlying muscular control in these animals is fully innate or whether there still exists a rapid maturation. We addressed this question by studying gait development in neonatal pigs through the analysis of spatio-temporal gait characteristics during locomotion at self-selected speed. To this end, we made video recordings of piglets walking along a corridor at several time points (from 0 h to 96 h). After digitization of the footfalls, we analysed self-selected speed and spatio-temporal characteristics (e.g. stride and step lengths, stride frequency and duty factor) to study dynamic similarity, intralimb coordination and interlimb coordination. To assess the variability of the gait pattern, left-right asymmetry was studied. To distinguish neuromotor maturation from effects caused by growth, both absolute and normalized data (according to the dynamic similarity concept) were included in the analysis. All normalized spatio-temporal variables reached stable values within 4 h of birth, with most of them showing little change after the age of 2 h. Most asymmetry indices showed stable values, hovering around 10%, within 8 h of birth. These results indicate that coordinated movement patterns are not entirely innate, but that a rapid neuromotor maturation, potentially also the result of the rearrangement or recombination of existing motor modules, takes place in these precocial animals. © 2017. Published by The Company of Biologists Ltd.

Skeleton-Based Abnormal Gait Detection

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Trong-Nguyen Nguyen

2016-10-01

Full Text Available Human gait analysis plays an important role in musculoskeletal disorder diagnosis. Detecting anomalies in human walking, such as shuffling gait, stiff leg or unsteady gait, can be difficult if the prior knowledge of such a gait pattern is not available. We propose an approach for detecting abnormal human gait based on a normal gait model. Instead of employing the color image, silhouette, or spatio-temporal volume, our model is created based on human joint positions (skeleton in time series. We decompose each sequence of normal gait images into gait cycles. Each human instant posture is represented by a feature vector which describes relationships between pairs of bone joints located in the lower body. Such vectors are then converted into codewords using a clustering technique. The normal human gait model is created based on multiple sequences of codewords corresponding to different gait cycles. In the detection stage, a gait cycle with normality likelihood below a threshold, which is determined automatically in the training step, is assumed as an anomaly. The experimental results on both marker-based mocap data and Kinect skeleton show that our method is very promising in distinguishing normal and abnormal gaits with an overall accuracy of 90.12%.

Exercise Alters Gait Pattern but Not Knee Load in Patients with Knee Osteoarthritis

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Ssu-Yu Chang

2016-01-01

Full Text Available Six female patients with bilateral medial knee OA and 6 healthy controls were recruited. Patients with knee OA received a 6-week physiotherapist-supervised and home-based exercise program. Outcome measures, including the Western Ontario and McMaster Universities Arthritis Index and Short Form-36 Health Survey as well as objective biomechanical indices were obtained at baseline and follow-up. After treatment, no significant difference was observed in the knee abductor moment (KAM, lever arm, and ground reaction force. We, however, observed significantly improved pain and physical function as well as altered gait patterns, including a higher hip flexor moment and hip extension angle with a faster walking speed. Although KAM was unchanged, patients with bilateral knee OA showed an improved walking speed and altered the gait pattern after 6 weeks of supervised exercise. This finding suggests that the exercise intervention improves proximal joint mechanics during walking and can be considered for patients with bilateral knee OA. Non-weight-bearing strengthening without external resistance combined with stretching exercise may be an option to improve pain and function in individuals with OA who cannot perform high resistance exercises owing to pain or other reasons.

Study on Gait Efficiency and Energy Cost of Below Knee Amputees After Therapeutic Practices

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Durbadal Biswas

2011-04-01

Full Text Available An earlier research advocated that a below knee amputee (BK with conventional trans-tibial prosthesis attains higher gait efficiency at lower energy cost with therapeutic practices of proper time and co-ordination in compare to normal subjects of similar physical parameters and quality of life. The present study focused on comparative analysis of energy cost and gait efficiency between a group of below knee amputees and a control group (normal subjects without amputation to indicate the consistency of the earlier findings. The subjects were selected with similar physical parameters and quality of life. Oxygen Uptake (VO2 and Heart Rate (HR were measured by Cosmed® k4 b2 analyzer system. Gait efficiency (p < 0.0001 was found higher with lower energy cost for BK amputees after therapeutic practices than control group. The therapeutic activities contributed to efficient gait pattern for amputees ensuring proper time and co-ordination with balance in consistence to the earlier research.

Vision-based gait impairment analysis for aided diagnosis.

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Ortells, Javier; Herrero-Ezquerro, María Trinidad; Mollineda, Ramón A

2018-02-12

Gait is a firsthand reflection of health condition. This belief has inspired recent research efforts to automate the analysis of pathological gait, in order to assist physicians in decision-making. However, most of these efforts rely on gait descriptions which are difficult to understand by humans, or on sensing technologies hardly available in ambulatory services. This paper proposes a number of semantic and normalized gait features computed from a single video acquired by a low-cost sensor. Far from being conventional spatio-temporal descriptors, features are aimed at quantifying gait impairment, such as gait asymmetry from several perspectives or falling risk. They were designed to be invariant to frame rate and image size, allowing cross-platform comparisons. Experiments were formulated in terms of two databases. A well-known general-purpose gait dataset is used to establish normal references for features, while a new database, introduced in this work, provides samples under eight different walking styles: one normal and seven impaired patterns. A number of statistical studies were carried out to prove the sensitivity of features at measuring the expected pathologies, providing enough evidence about their accuracy. Graphical Abstract Graphical abstract reflecting main contributions of the manuscript: at the top, a robust, semantic and easy-to-interpret feature set to describe impaired gait patterns; at the bottom, a new dataset consisting of video-recordings of a number of volunteers simulating different patterns of pathological gait, where features were statistically assessed.

An automated procedure for identification of a person using gait analysis

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Alena Galajdová

2016-10-01

Full Text Available Different biometric methods are available for identification purpose of a person. The most commonly used are fingerprints, but there are also other biometric methods such as voice, morphology of ears, structure of iris and so on. In some cases, it is required to identify a person according to his/her biomechanical parameters or even his/her gait pattern. Gait is an outstanding biometric behavioural characteristic that is not widely used yet for identification purposes because efficient and proven automated processes are not yet available. Several systems and gait pattern databases have been developed for rapid evaluation and processing of gait. This article describes an original automated evaluation procedure of gait pattern and identification of unique gait parameters for automatic identification purposes.

Mind your step: metabolic energy cost while walking an enforced gait pattern.

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Wezenberg, D; de Haan, A; van Bennekom, C A M; Houdijk, H

2011-04-01

The energy cost of walking could be attributed to energy related to the walking movement and energy related to balance control. In order to differentiate between both components we investigated the energy cost of walking an enforced step pattern, thereby perturbing balance while the walking movement is preserved. Nine healthy subjects walked three times at comfortable walking speed on an instrumented treadmill. The first trial consisted of unconstrained walking. In the next two trials, subject walked while following a step pattern projected on the treadmill. The steps projected were either composed of the averaged step characteristics (periodic trial), or were an exact copy including the variability of the steps taken while walking unconstrained (variable trial). Metabolic energy cost was assessed and center of pressure profiles were analyzed to determine task performance, and to gain insight into the balance control strategies applied. Results showed that the metabolic energy cost was significantly higher in both the periodic and variable trial (8% and 13%, respectively) compared to unconstrained walking. The variation in center of pressure trajectories during single limb support was higher when a gait pattern was enforced, indicating a more active ankle strategy. The increased metabolic energy cost could originate from increased preparatory muscle activation to ensure proper foot placement and a more active ankle strategy to control for lateral balance. These results entail that metabolic energy cost of walking can be influenced significantly by control strategies that do not necessary alter global gait characteristics. Copyright © 2011 Elsevier B.V. All rights reserved.

Changes of gait pattern in children with Charcot-Marie-Tooth disease type 1A: a 18 months follow-up study.

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Ferrarin, Maurizio; Lencioni, Tiziana; Rabuffetti, Marco; Moroni, Isabella; Pagliano, Emanuela; Pareyson, Davide

2013-07-02

In a previous study we identified 3 different gait patterns in a group of children with CMT1A disease: Normal-like (NL), Foot-drop (FD), Foot-drop and Push-off Deficit (FD&POD). Goal of the present study was to perform a follow-up evaluation of the same group of patients to analyze possible changes of gait features in relation to disease progression or specific therapy. Nineteen children with CMT1A were evaluated clinically (CMT-Examination Score and Overall Neuropathy Limitation Scale) and through gait analysis 18.2±1.5 months after a baseline evaluation. Meanwhile, 3 of them had foot surgery. Fifteen out of the 16 non-operated patients significantly changed at least one of the two parameters associated to primary signs (FD and/or POD). Eleven participants worsened at least one parameter and 9 improved one parameter. CMTES significantly worsened for the group of non-operated patients. However, there was no change in CMTES score in 4 patients and in ONLS score in 11. At subgroup level, participants originally belonging to NL group showed a trend towards a foot-drop deficit (-15%, ns); FD and FD&POD subgroups did not change their primary signs, although significant changes were identified individually. All 3 patients operated have improved push-off and proximal joint patterns during walking. Clinical scores did not change within any sub-group. Subtle changes occurring in 1.5 year in gait features of CMT1A children can be instrumentally identified. Such changes show a large inter-subject variability, with some patients even improving their walking pattern. There is anecdotal evidence that foot surgery may improve the push-off phase of gait.

The Novel Quantitative Technique for Assessment of Gait Symmetry Using Advanced Statistical Learning Algorithm

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Jianning Wu

2015-01-01

Full Text Available The accurate identification of gait asymmetry is very beneficial to the assessment of at-risk gait in the clinical applications. This paper investigated the application of classification method based on statistical learning algorithm to quantify gait symmetry based on the assumption that the degree of intrinsic change in dynamical system of gait is associated with the different statistical distributions between gait variables from left-right side of lower limbs; that is, the discrimination of small difference of similarity between lower limbs is considered the reorganization of their different probability distribution. The kinetic gait data of 60 participants were recorded using a strain gauge force platform during normal walking. The classification method is designed based on advanced statistical learning algorithm such as support vector machine algorithm for binary classification and is adopted to quantitatively evaluate gait symmetry. The experiment results showed that the proposed method could capture more intrinsic dynamic information hidden in gait variables and recognize the right-left gait patterns with superior generalization performance. Moreover, our proposed techniques could identify the small significant difference between lower limbs when compared to the traditional symmetry index method for gait. The proposed algorithm would become an effective tool for early identification of the elderly gait asymmetry in the clinical diagnosis.

The novel quantitative technique for assessment of gait symmetry using advanced statistical learning algorithm.

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Wu, Jianning; Wu, Bin

2015-01-01

The accurate identification of gait asymmetry is very beneficial to the assessment of at-risk gait in the clinical applications. This paper investigated the application of classification method based on statistical learning algorithm to quantify gait symmetry based on the assumption that the degree of intrinsic change in dynamical system of gait is associated with the different statistical distributions between gait variables from left-right side of lower limbs; that is, the discrimination of small difference of similarity between lower limbs is considered the reorganization of their different probability distribution. The kinetic gait data of 60 participants were recorded using a strain gauge force platform during normal walking. The classification method is designed based on advanced statistical learning algorithm such as support vector machine algorithm for binary classification and is adopted to quantitatively evaluate gait symmetry. The experiment results showed that the proposed method could capture more intrinsic dynamic information hidden in gait variables and recognize the right-left gait patterns with superior generalization performance. Moreover, our proposed techniques could identify the small significant difference between lower limbs when compared to the traditional symmetry index method for gait. The proposed algorithm would become an effective tool for early identification of the elderly gait asymmetry in the clinical diagnosis.

Altering length and velocity feedback during a neuro-musculoskeletal simulation of normal gait contributes to hemiparetic gait characteristics.

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Jansen, Karen; De Groote, Friedl; Aerts, Wouter; De Schutter, Joris; Duysens, Jacques; Jonkers, Ilse

2014-04-30

Spasticity is an important complication after stroke, especially in the anti-gravity muscles, i.e. lower limb extensors. However the contribution of hyperexcitable muscle spindle reflex loops to gait impairments after stroke is often disputed. In this study a neuro-musculoskeletal model was developed to investigate the contribution of an increased length and velocity feedback and altered reflex modulation patterns to hemiparetic gait deficits. A musculoskeletal model was extended with a muscle spindle model providing real-time length and velocity feedback of gastrocnemius, soleus, vasti and rectus femoris during a forward dynamic simulation (neural control model). By using a healthy subject's base muscle excitations, in combination with increased feedback gains and altered reflex modulation patterns, the effect on kinematics was simulated. A foot-ground contact model was added to account for the interaction effect between the changed kinematics and the ground. The qualitative effect i.e. the directional effect and the specific gait phases where the effect is present, on the joint kinematics was then compared with hemiparetic gait deviations reported in the literature. Our results show that increased feedback in combination with altered reflex modulation patterns of soleus, vasti and rectus femoris muscle can contribute to excessive ankle plantarflexion/inadequate dorsiflexion, knee hyperextension/inadequate flexion and increased hip extension/inadequate flexion during dedicated gait cycle phases. Increased feedback of gastrocnemius can also contribute to excessive plantarflexion/inadequate dorsiflexion, however in combination with excessive knee and hip flexion. Increased length/velocity feedback can therefore contribute to two types of gait deviations, which are both in accordance with previously reported gait deviations in hemiparetic patients. Furthermore altered modulation patterns, in particular the reduced suppression of the muscle spindle feedback during

A DATA-MINING BASED METHOD FOR THE GAIT PATTERN ANALYSIS

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Marcelo Rudek

2015-12-01

Full Text Available The paper presents a method developed for the gait classification based on the analysis of the trajectory of the pressure centres (CoP extracted from the contact points of the feet with the ground during walking. The data acquirement is performed ba means of a walkway with embedded tactile sensors. The proposed method includes capturing procedures, standardization of data, creation of an organized repository (data warehouse, and development of a process mining. A graphical analysis is applied to looking at the footprint signature patterns. The aim is to obtain a visual interpretation of the grouping by situating it into the normal walking patterns or deviations associated with an individual way of walking. The method consists of data classification automation which divides them into healthy and non-healthy subjects in order to assist in rehabilitation treatments for the people with related mobility problems.

Older adults adopted more cautious gait patterns when walking in socks than barefoot.

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Tsai, Yi-Ju; Lin, Sang-I

2013-01-01

Walking barefoot or in socks is common for ambulating indoors and has been reported to be associated with increased risk of falls and related injuries in the elderly. This study sought to determine if gait patterns differed between these two conditions for young and older adults. A motion analysis system was used to record and calculate the stride characteristics and motion of the body's center of mass (COM) of 21 young and 20 older adults. For the walking tasks, the participants walked on a smooth floor surface at their preferred speed either barefoot or in socks in a random order. The socks were commercially available and commonly used. The results demonstrated that while walking in socks, compared with walking barefoot, older adults adopted a more cautious gait pattern including decreased walking speed and shortened stride length as well as reduced COM minimal velocity during the single limb support phase. Young adults, however, did not demonstrate significant changes. These findings suggest that walking with socks might present a greater balance threat for older adults. Clinically, safety precautions about walking in socks should be considered to be given to older adults, especially those with balance deficits. Copyright © 2012 Elsevier B.V. All rights reserved.

Characterization of a cerebral palsy-like model in rats: Analysis of gait pattern and of brain and spinal cord motor areas.

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Dos Santos, Adriana Souza; de Almeida, Wellington; Popik, Bruno; Sbardelotto, Bruno Marques; Torrejais, Márcia Miranda; de Souza, Marcelo Alves; Centenaro, Lígia Aline

2017-08-01

In an attempt to propose an animal model that reproduces in rats the phenotype of cerebral palsy, this study evaluated the effects of maternal exposure to bacterial endotoxin associated with perinatal asphyxia and sensorimotor restriction on gait pattern, brain and spinal cord morphology. Two experimental groups were used: Control Group (CTG) - offspring of rats injected with saline during pregnancy and Cerebral Palsy Group (CPG) - offspring of rats injected with lipopolysaccharide during pregnancy, submitted to perinatal asphyxia and sensorimotor restriction for 30days. At 29days of age, the CPG exhibited coordination between limbs, weight-supported dorsal steps or weight-supported plantar steps with paw rotation. At 45days of age, CPG exhibited plantar stepping with the paw rotated in the balance phase. An increase in the number of glial cells in the primary somatosensory cortex and dorsal striatum were observed in the CPG, but the corpus callosum thickness and cross-sectional area of lateral ventricle were similar between studied groups. No changes were found in the number of motoneurons, glial cells and soma area of the motoneurons in the ventral horn of spinal cord. The combination of insults in the pre, peri and postnatal periods produced changes in hindlimbs gait pattern of animals similar to those observed in diplegic patients, but motor impairments were attenuated over time. Besides, the greater number of glial cells observed seems to be related to the formation of a glial scar in important sensorimotor brain areas. Copyright © 2017 ISDN. Published by Elsevier Ltd. All rights reserved.

Gait deficiencies associated with peripheral artery disease are different than chronic obstructive pulmonary disease.

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McCamley, John D; Pisciotta, Eric J; Yentes, Jennifer M; Wurdeman, Shane R; Rennard, Stephen I; Pipinos, Iraklis I; Johanning, Jason M; Myers, Sara A

2017-09-01

Previous studies have indicated that patients with peripheral artery disease (PAD), display significant differences in their kinetic and kinematic gait characteristics when compared to healthy, aged-matched controls. The ability of patients with chronic obstructive pulmonary disease (COPD) to ambulate is also limited. These limitations are likely due to pathology-driven muscle morphology and physiology alterations establish in PAD and COP, respectively. Gait changes in PAD were compared to gait changes due to COPD to further understand how altered limb muscle due to disease can alter walking patterns. Both groups were independently compared to healthy controls. It was hypothesized that both patients with PAD and COPD would demonstrate similar differences in gait when compared to healthy controls. Patients with PAD (n=25), patients with COPD (n=16), and healthy older control subjects (n=25) performed five walking trials at self-selected speeds. Sagittal plane joint kinematic and kinetic group means were compared. Peak values for hip flexion angle, braking impulse, and propulsive impulse were significantly reduced in patients with symptomatic PAD compared to patients with COPD. After adjusting for walking velocity, significant reductions (pgait patterns are impaired for patients with PAD, this is not apparent for patients with COPD (without PAD). PAD (without COPD) causes changes to the muscle function of the lower limbs that affects gait even when subjects walk from a fully rested state. Altered muscle function in patients with COPD does not have a similar effect. Copyright © 2017 Elsevier B.V. All rights reserved.

Differential associations between dual-task walking abilities and usual gait patterns in healthy older adults-Results from the Baltimore Longitudinal Study of Aging.

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Ko, Seung-Uk; Jerome, Gerald J; Simonsick, Eleanor M; Studenski, Stephanie; Hausdorff, Jeffrey M; Ferrucci, Luigi

2018-04-27

It is well established that facing a cognitive challenge while carrying out a motor task interferes with the motor task performance, and in general the ability of handling a dual-task declines progressively with aging. However, the reasons for this decline have not been fully elucidated. Understanding the association between usual-walking gait patterns and dual-task walking performance may provide new insights into the mechanisms that lead to gait deterioration in normal aging and its link to motor and cognitive function. Our aim was to assess usual gait parameters in kinematics and kinetics to understand how these parameters are related with a specific task in dual-task walking. We hypothesized that difficulty in dual-task walking would be associated with gait deteriorations as reflected in range of motion and mechanical work expenditure. We tested this hypothesis by quantifying the gait of 383 participants in the Baltimore Longitudinal Study of Aging (68% of whom successfully completed the dual-task walk, 21% failed the motor task, and 11% failed the cognitive task). Compared to successful performers, participants who failed the single motor task had slower gait speed, shorter stride length, higher cadence, and lower range of motion in the knee and ankle joints (p task while walking had longer double support time (p = 0.003), and greater knee absorptive mechanical work (p = 0. 001) and lower ankle generative mechanical work (p task walking may be useful for monitoring subtle and diverse gait deteriorations in aging and possibly for designing interventions for maintaining and regaining proper gait patterns in older adults. Copyright © 2018 Elsevier B.V. All rights reserved.

An accelerometry-based comparison of 2 robotic assistive devices for treadmill training of gait.

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Regnaux, Jean-Philippe; Saremi, Kaveh; Marehbian, Jon; Bussel, Bernard; Dobkin, Bruce H

2008-01-01

Two commercial robotic devices, the Gait Trainer (GT) and the Lokomat (LOKO), assist task-oriented practice of walking. The gait patterns induced by these motor-driven devices have not been characterized and compared. A healthy participant chose the most comfortable gait pattern on each device and for treadmill (TM) walking at 1, 2 (maximum for the GT), and 3 km/h and over ground at similar speeds. A system of accelerometers on the thighs and feet allowed the calculation of spatiotemporal features and accelerations during the gait cycle. At the 1 and 2 km/h speed settings, single-limb stance times were prolonged on the devices compared with overground walking. Differences on the LOKO were decreased by adjusting the hip and knee angles and step length. At the 3 km/h setting, the LOKO approximated the participant's overground parameters. Irregular accelerations and decelerations from toe-off to heel contact were induced by the devices, especially at slower speeds. The LOKO and GT impose mechanical constraints that may alter leg accelerations-decelerations during stance and swing phases, as well as stance duration, especially at their slower speed settings, that are not found during TM and overground walking. The potential impact of these perturbations on training to improve gait needs further study.

Effects of walking speed on asymmetry and bilateral coordination of gait

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Plotnik, Meir; Bartsch, Ronny P.; Zeev, Aviva; Giladi, Nir; Hausdorff, Jeffery M.

2013-01-01

The mechanisms regulating the bilateral coordination of gait in humans are largely unknown. Our objective was to study how bilateral coordination changes as a result of gait speed modifications during over ground walking. 15 young adults wore force sensitive insoles that measured vertical forces used to determine the timing of the gait cycle events under three walking conditions (i.e., usual-walking, fast and slow). Ground reaction force impact (GRFI) associated with heel-strikes was also quantified, representing the potential contribution of sensory feedback to the regulation of gait. Gait asymmetry (GA) was quantified based on the differences between right and left swing times and the bilateral coordination of gait was assessed using the phase coordination index (PCI), a metric that quantifies the consistency and accuracy of the anti-phase stepping pattern. GA was preserved in the three different gait speeds. PCI was higher (reduced coordination) in the slow gait condition, compared to usual-walking (3.51% vs. 2.47%, respectively, p=0.002), but was not significantly affected in the fast condition. GRFI values were lower in the slow walking as compared to usual-walking and higher in the fast walking condition (pgait related changes in PCI were not associated with the slowed gait related changes in GRFI. The present findings suggest that left-right anti-phase stepping is similar in normal and fast walking, but altered during slowed walking. This behavior might reflect a relative increase in attention resources required to regulate a slow gait speed, consistent with the possibility that cortical function and supraspinal input influences the bilateral coordination of gait. PMID:23680424

Gait pattern of severely disabled hemiparetic subjects on a new controlled gait trainer as compared to assisted treadmill walking with partial body weight support.

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Hesse, S; Uhlenbrock, D; Sarkodie-Gyan, T

1999-10-01

To investigate to what extent and with how much therapeutic effort nonambulatory stroke patients could train a gait-like movement on a newly developed, machine-supported gait trainer. Open study comparing the movement on the gait trainer with assisted walking on the treadmill. Motion analysis laboratory of a rehabilitation centre. Fourteen chronic, nonambulatory hemiparetic patients. Complex gait analysis while training on the gait trainer and while walking on the treadmill. Gait kinematics, kinesiological EMG of several lower limb muscles and the required assistance. Patients could train a gait-like movement on the gait trainer, characterized kinematically by a perfect symmetry, larger hip extension during stance, less knee flexion and less ankle plantar flexion during swing as compared to treadmill walking (p gait trainer (p gait trainer offered severely disabled hemiparetic subjects the possibility of training a gait-like, highly symmetrical movement with a favourable facilitation of relevant anti-gravity muscles. At the same time, the effort required of the therapists was reduced.

Energy Cost and Gait Efficiency of Below-Knee Amputee and Normal Subject with Similar Physical Parameters & Quality of Life: A Comparative Case Study

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Durbadal Biswas

2010-10-01

Full Text Available The study focused on the comparative analysis of energy cost and gait efficiency between a below knee (BK amputee and a reference subject (without amputation. It also attempted to indicate the specific feature responsible for a controlled gait with optimum energy cost for BK amputees. Selection criteria of the subjects were similar physical parameters and quality of life studied with WHOQOL-100 quality of life assessment. A Cosmed® k4 b2 Respiratory Analyzer system was used for the measurement of Oxygen Uptake (VO2, Energy Expenditure per minute (EE and Heart Rate (HR. Gait efficiency (p < 0.0002 was found higher for BK amputee than normal subject. The therapeutic activities and mainly walking rhythm contributed to improve the mobility & balance. This ensures the optimum time & co-ordination of movements and hence improves the gait efficiency for the BK amputee. Comparison with control group was performed to validate the data.

Upper limb movement analysis during gait in multiple sclerosis patients.

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Elsworth-Edelsten, Charlotte; Bonnefoy-Mazure, Alice; Laidet, Magali; Armand, Stephane; Assal, Frederic; Lalive, Patrice; Allali, Gilles

2017-08-01

Gait disorders in multiple sclerosis (MS) are well studied; however, no previous study has described upper limb movements during gait. However, upper limb movements have an important role during locomotion and can be altered in MS patients due to direct MS lesions or mechanisms of compensation. The aim of this study was to describe the arm movements during gait in a population of MS patients with low disability compared with a healthy control group. In this observational study we analyzed the arm movements during gait in 52 outpatients (mean age: 39.7±9.6years, female: 40%) with relapsing-remitting MS with low disability (mean EDSS: 2±1) and 25 healthy age-matched controls using a 3-dimension gait analysis. MS patients walked slower, with increased mean elbow flexion and decreased amplitude of elbow flexion (ROM) compared to the control group, whereas shoulder and hand movements were similar to controls. These differences were not explained by age or disability. Upper limb alterations in movement during gait in MS patients with low disability can be characterized by an increase in mean elbow flexion and a decrease in amplitude (ROM) for elbow flexion/extension. This upper limb movement pattern should be considered as a new component of gait disorders in MS and may reflect subtle motor deficits or the use of compensatory mechanisms. Copyright © 2017 Elsevier B.V. All rights reserved.

Robotic gait trainer in water: development of an underwater gait-training orthosis.

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Miyoshi, Tasuku; Hiramatsu, Kazuaki; Yamamoto, Shin-Ichiro; Nakazawa, Kimitaka; Akai, Masami

2008-01-01

To develop a robotic gait trainer that can be used in water (RGTW) and achieve repetitive physiological gait patterns to improve the movement dysfunctions. The RGTW is a hip-knee-ankle-foot orthosis with pneumatic actuators; the control software was developed on the basis of the angular motions of the hip and knee joint of a healthy subject as he walked in water. Three-dimensional motions and electromyographic (EMG) activities were recorded in nine healthy subjects to evaluate the efficacy of using the RGTW while walking on a treadmill in water. The device could preserve the angular displacement patterns of the hip and knee and foot trajectories under all experimental conditions. The tibialis anterior EMG activities in the late swing phase and the biceps femoris throughout the stance phase were reduced whose joint torques were assisted by the RGTW while walking on a treadmill in water. Using the RGTW could expect not only the effect of the hydrotherapy but also the standard treadmill gait training, in particular, and may be particularly effective for treating individuals with hip joint movement dysfunction.

Effect of a nonsurgical treatment program on the gait pattern of idiopathic toe walking: a case report

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Szopa A

2016-02-01

Full Text Available Andrzej Szopa,1 Małgorzata Domagalska-Szopa,2 Weronika Gallert-Kopyto,1 Wojciech Kiebzak,3 Ryszard Plinta4 1Department of Physiotherapy, 2Department of Medical Rehabilitation, School of Health Sciences, Medical University of Silesia, Katowice, 3Faculty of Health Sciences, Jan Kochanowski University, Kielce, 4Department of Adapted Physical Activity and Sport, School of Health Sciences, Medical University of Silesia, Katowice, Poland Background: Recent studies have reported many possibilities for the treatment of idiopathic toe walking (ITW; however, none of them have been sufficiently documented. The purpose of this case study was to document the evolution of the gait pattern of a child with severe ITW using the Gillette Gait Index before and after the third and sixth weeks, a nonsurgical treatment program and then every 3 months to 1 year from the start of the treatment. This is significant because the case study shows that a nonsurgical treatment program can be an alternative treatment method for children with severe ITW.Case description: The case study involved a 5-year-old boy diagnosed with severe ITW. An orthopedist recommended a surgical treatment, but his parents refused to provide consent.Intervention: The subject participated in a 12-week nonsurgical treatment program that used tone-inhibiting casts (TICs combined with physiotherapy based on neurodevelopmental treatment principles. The treatment protocol included the following: 1 precast preparation; 2 TICs with treatment; and 3 post-cast treatment to improve the gait pattern.Outcomes: After treatment with TICs, the range of motion of ankle dorsiflexion during stance had increased, resulting in an almost normalized gait. The patient stopped toe walking for at least 1 year.Discussion: This study demonstrates that nonsurgical treatment should be considered first, with surgical options reserved for resistant cases; however, further research is required given the current lack of knowledge

Gait Strategy in Patients with Ehlers-Danlos Syndrome Hypermobility Type: A Kinematic and Kinetic Evaluation Using 3D Gait Analysis

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Galli, Manuela; Cimolin, Veronica; Rigoldi, Chiara; Castori, Marco; Celletti, Claudia; Albertini, Giorgio; Camerota, Filippo

2011-01-01

The aim of this study was to quantify the gait patterns of adults with joint hypermobility syndrome/Ehlers-Danlos syndrome (JHS/EDS-HT) hypermobility type, using Gait Analysis. We quantified the gait strategy in 12 JHS/EDS-HT adults individuals (age: 43.08 + 6.78 years) compared to 20 healthy controls (age: 37.23 plus or minus 8.91 years), in…

Gait analysis in anorexia and bulimia nervosa.

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Cimolin, Veronica; Galli, Manuela; Vismara, Luca; Vimercati, Sara Laura; Precilios, Helmer; Cattani, Laila; Fabris De Souza, Shirley; Petroni, Maria Letizia; Capodaglio, Paolo

2013-09-13

Anorexia (AN) and Bulimia Nervosa (BN) are two common eating disorders, which appear to share some reduced motor capacities, such as a reduced balance. The presence and the extent of other motor disorders have not been investigated in a comprehensive way. The aim of this study was to quantify gait pattern in AN and BN individuals in order to ascertain possible differences from the normality range and provide novel data for developing some evidence-based rehabilitation strategies. Nineteen AN patients (age 30.16+9.73) and 20 BN patients (age 26.8+8.41) were assessed with quantitative 3D computerized Gait Analysis. Results were compared with a group of healthy controls (CG; 30.7+5.6). AN and BN patients were characterized by different gait strategies compared to CG. Spatio-temporal parameters indicated shorter step length, with AN showing the shortest values. AN walked slower than BN and CG. As for kinematics, AN and BN showed a nonphysiologic pattern at pelvis and hip level on the sagittal and frontal plane, with BN yielding the most abnormal values. Both AN and BN patients were characterized by high ankle plantar flexion capacity at toe-off when compared to CG. As for ankle kinetics, both AN and BN showed physiologic patterns. Stiffness at hip level was close to CG in both pathologic groups; at the ankle level, stiffness was significantly decreased in both groups, with AN displaying lower values. Both AN and BN were characterized by an altered gait pattern compared to CG. Biomechanical differences were evident mainly at pelvis and hip level. Loss of lean mass may lead to musculoskeletal adaptation, ultimately causing alterations in the gait pattern.

Analysis of Gait Pattern to Recognize the Human Activities

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Jay Prakash Gupta

2014-09-01

Full Text Available Human activity recognition based on the computer vision is the process of labelling image sequences with action labels. Accurate systems for this problem are applied in areas such as visual surveillance, human computer interaction and video retrieval. The challenges are due to variations in motion, recording settings and gait differences. Here we propose an approach to recognize the human activities through gait. Activity recognition through Gait is the process of identifying an activity by the manner in which they walk. The identification of human activities in a video, such as a person is walking, running, jumping, jogging etc are important activities in video surveillance. We contribute the use of Model based approach for activity recognition with the help of movement of legs only. Experimental results suggest that our method are able to recognize the human activities with a good accuracy rate and robust to shadows present in the videos.

Gait Pattern in Two Rare Genetic Conditions Characterized by Muscular Hypotonia: Ehlers-Danlos and Prader-Willi Syndrome

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Cimolin, Veronica; Galli, Manuela; Vismara, Luca; Grugni, Graziano; Camerota, Filippo; Celletti, Claudia; Albertini, Giorgio; Rigoldi, Chiara; Capodaglio, Paolo

2011-01-01

This study aimed to quantify and compare the gait pattern in Ehlers-Danlos (EDS) and Prader-Willi syndrome (PWS) patients to provide data for developing evidence-based rehabilitation strategies. Twenty EDS and 19 PWS adult patients were evaluated with an optoelectronic system and force platforms for measuring kinematic and kinetic parameters…

Effects of obesity and chronic low back pain on gait

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Cimolin, Veronica; Vismara, Luca; Galli, Manuela; Zaina, Fabio; Negrini, Stefano; Capodaglio, Paolo

2011-01-01

Abstract Background Obesity is often associated with low back pain (LBP). Despite empirical evidence that LBP induces gait abnormalities, there is a lack of quantitative analysis of the combined effect of obesity and LBP on gait. The aim of our study was to quantify the gait pattern of obese subjects with and without LBP and normal-mass controls by using Gait Analysis (GA), in order to investigate the cumulative effects of obesity and LBP on gait. Methods Eight obese females with chronic LBP ...

Use of Photogrammetry and Biomechanical Gait analysis to Identify Individuals

DEFF Research Database (Denmark)

Larsen, Peter Kastmand; Simonsen, Erik Bruun; Lynnerup, Niels

Photogrammetry and recognition of gait patterns are valuable tools to help identify perpetrators based on surveillance recordings. We have found that stature but only few other measures have a satisfying reproducibility for use in forensics. Several gait variables with high recognition rates were...... found. Especially the variables located in the frontal plane are interesting due to large inter-individual differences in time course patterns. The variables with high recognition rates seem preferable for use in forensic gait analysis and as input variables to waveform analysis techniques...

Gait Patterns in Hemiplegic Children with Cerebral Palsy: Comparison of Right and Left Hemiplegia

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Galli, Manuela; Cimolin, Veronica; Rigoldi, Chiara; Tenore, Nunzio; Albertini, Giorgio

2010-01-01

The aims of this study are to compare quantitatively the gait strategy of the right and left hemiplegic children with Cerebral Palsy (CP) using gait analysis. The gait strategy of 28 right hemiparetic CP (RHG) and 23 left hemiparetic CP (LHG) was compared using gait analysis (spatio-temporal and kinematic parameters) and considering the hemiplegic…

Probabilistic Gait Classification in Children with Cerebral Palsy: A Bayesian Approach

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Van Gestel, Leen; De Laet, Tinne; Di Lello, Enrico; Bruyninckx, Herman; Molenaers, Guy; Van Campenhout, Anja; Aertbelien, Erwin; Schwartz, Mike; Wambacq, Hans; De Cock, Paul; Desloovere, Kaat

2011-01-01

Three-dimensional gait analysis (3DGA) generates a wealth of highly variable data. Gait classifications help to reduce, simplify and interpret this vast amount of 3DGA data and thereby assist and facilitate clinical decision making in the treatment of CP. CP gait is often a mix of several clinically accepted distinct gait patterns. Therefore,…

Crowd-Sourced Amputee Gait Data: A Feasibility Study Using YouTube Videos of Unilateral Trans-Femoral Gait.

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James Gardiner

Full Text Available Collecting large datasets of amputee gait data is notoriously difficult. Additionally, collecting data on less prevalent amputations or on gait activities other than level walking and running on hard surfaces is rarely attempted. However, with the wealth of user-generated content on the Internet, the scope for collecting amputee gait data from alternative sources other than traditional gait labs is intriguing. Here we investigate the potential of YouTube videos to provide gait data on amputee walking. We use an example dataset of trans-femoral amputees level walking at self-selected speeds to collect temporal gait parameters and calculate gait asymmetry. We compare our YouTube data with typical literature values, and show that our methodology produces results that are highly comparable to data collected in a traditional manner. The similarity between the results of our novel methodology and literature values lends confidence to our technique. Nevertheless, clear challenges with the collection and interpretation of crowd-sourced gait data remain, including long term access to datasets, and a lack of validity and reliability studies in this area.

Crowd-Sourced Amputee Gait Data: A Feasibility Study Using YouTube Videos of Unilateral Trans-Femoral Gait.

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Gardiner, James; Gunarathne, Nuwan; Howard, David; Kenney, Laurence

2016-01-01

Collecting large datasets of amputee gait data is notoriously difficult. Additionally, collecting data on less prevalent amputations or on gait activities other than level walking and running on hard surfaces is rarely attempted. However, with the wealth of user-generated content on the Internet, the scope for collecting amputee gait data from alternative sources other than traditional gait labs is intriguing. Here we investigate the potential of YouTube videos to provide gait data on amputee walking. We use an example dataset of trans-femoral amputees level walking at self-selected speeds to collect temporal gait parameters and calculate gait asymmetry. We compare our YouTube data with typical literature values, and show that our methodology produces results that are highly comparable to data collected in a traditional manner. The similarity between the results of our novel methodology and literature values lends confidence to our technique. Nevertheless, clear challenges with the collection and interpretation of crowd-sourced gait data remain, including long term access to datasets, and a lack of validity and reliability studies in this area.

Self-esteem recognition based on gait pattern using Kinect.

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Sun, Bingli; Zhang, Zhan; Liu, Xingyun; Hu, Bin; Zhu, Tingshao

2017-10-01

Self-esteem is an important aspect of individual's mental health. When subjects are not able to complete self-report questionnaire, behavioral assessment will be a good supplement. In this paper, we propose to use gait data collected by Kinect as an indicator to recognize self-esteem. 178 graduate students without disabilities participate in our study. Firstly, all participants complete the 10-item Rosenberg Self-Esteem Scale (RSS) to acquire self-esteem score. After completing the RRS, each participant walks for two minutes naturally on a rectangular red carpet, and the gait data are recorded using Kinect sensor. After data preprocessing, we extract a few behavioral features to train predicting model by machine learning. Based on these features, we build predicting models to recognize self-esteem. For self-esteem prediction, the best correlation coefficient between predicted score and self-report score is 0.45 (pself-esteem with a fairly good criterion validity. The gait predicting model can be taken as a good supplementary method to measure self-esteem. Copyright © 2017 Elsevier B.V. All rights reserved.

Adaptive changes in spatiotemporal gait characteristics in women during pregnancy.

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Błaszczyk, Janusz W; Opala-Berdzik, Agnieszka; Plewa, Michał

2016-01-01

Spatiotemporal gait cycle characteristics were assessed at early (P1), and late (P2) pregnancy, as well as at 2 months (PP1) and 6 months (PP2) postpartum. A substantial decrease in walking speed was observed throughout the pregnancy, with the slowest speed (1±0.2m/s) being during the third trimester. Walking at slower velocity resulted in complex adaptive adjustments to their spatiotemporal gait pattern, including a shorter step length and an increased duration of both their stance and double-support phases. Duration of the swing phase remained the least susceptible to changes. Habitual walking velocity (1.13±0.2m/s) and the optimal gait pattern were fully recovered 6 months after childbirth. Documented here adaptive changes in the preferred gait pattern seem to result mainly from the altered body anthropometry leading to temporary balance impairments. All the observed changes within stride cycle aimed to improve gait safety by focusing on its dynamic stability. The pregnant women preferred to walk at a slower velocity which allowed them to spend more time in double-support compared with their habitual pattern. Such changes provided pregnant women with a safer and more tentative ambulation that reduced the single-support period and, hence, the possibility of instability. As pregnancy progressed a significant increase in stance width and a decrease in step length was observed. Both factors allow also for gait stability improvement. Copyright © 2015 Elsevier B.V. All rights reserved.

A synergy perspective on gait – over-ground vs. treadmill walking

DEFF Research Database (Denmark)

Læssøe, Uffe; Madeleine, Pascal

on movements has proposed that elemental and performance variables may represent good and bad components of variability [2]. We suggest that the gait pattern can be regarded as a movement synergy in which medio-lateral deviation in one stride can be corrected during the next stride (the elemental variables......). Such corrections ensure a straight gait path (the performance variable). AIM: The aim of this study was to apply a synergy approach to gait analysis by comparing over-ground and treadmill walking. The treadmill was hypothesized to demand a less variable walking path resulting in a larger good/bad variability ratio...... of the strides, and bad variance with respect to a similar line with a negative slope. The good/bad variance ratio was calculated and the difference between treadmill and over-ground walking was finally evaluated. RESULTS: The good/bad variance ratio for over-ground walking was 1.7 (CI95%: 1.5-2.0). When walking...

Energy evaluation of a bio-inspired gait modulation method for quadrupedal locomotion.

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Fukuoka, Yasuhiro; Fukino, Kota; Habu, Yasushi; Mori, Yoshikazu

2015-08-04

We have proposed a bio-inspired gait modulation method, by means of which a simulated quadruped model can successfully perform smooth, autonomous gait transitions from a walk to a trot to a gallop, as observed in animals. The model is equipped with a rhythm generator called a central pattern generator (CPG) for each leg. The lateral neighbouring CPGs are mutually and inhibitorily coupled, and the CPG network is hardwired to produce a trot. Adding only the simple feedback of body tilt to each CPG, which was based on input from the postural reflex, led to the emergence of un-programmed walking and galloping at low and high speeds, respectively. Although this autonomous gait transition was a consequence of postural adaptation, it coincidentally also resulted in the minimization of energy consumption, as observed in real animals. In simulations at a variety of constant speeds the energy cost was lower for walking at low speeds and for galloping at high speeds than it was for trotting. Moreover, each gait transition occurred at the optimal speed, such that the model minimised its energy consumption. Thus, gait transitions in simulations that included the bio-inspired gait modulation method were similar to those observed in animals, even from the perspective of energy consumption. This method should therefore be a preferred choice for motion generation and control in biomimetic quadrupedal locomotion.

Gait analysis of adults with generalised joint hypermobility

DEFF Research Database (Denmark)

Simonsen, Erik B; Tegner, Heidi; Alkjær, Tine

2012-01-01

BACKGROUND: The majority of adults with Generalised Joint Hypermobility experience symptoms such as pain and joint instability, which is likely to influence their gait pattern. Accordingly, the purpose of the present project was to perform a biomechanical gait analysis on a group of patients...

Electromyographic Pattern during Gait Initiation Differentiates Yoga Practitioners among Physically Active Older Subjects

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Thierry Lelard

2017-06-01

Full Text Available During gait initiation, postural adjustments are needed to deal with balance and movement. With aging, gait initiation changes and reflects functional degradation of frailty individuals. However, physical activities have demonstrated beneficial effects of daily motor tasks. The aim of our study was to compare center of pressure (COP displacement and ankle muscle co-activation during gait initiation in two physically active groups: a group of walkers (n = 12; mean age ± SD 72.6 ± 3.2 years and a yoga group (n = 11; 71.5 ± 3.8 years. COP trajectory and electromyography of leg muscles were recorded simultaneously during five successive trials of gait initiation. Our main finding was that yoga practitioners had slower COP displacements (p < 0.01 and lower leg muscles % of coactivation (p < 0.01 in comparison with walkers. These parameters which characterized gait initiation control were correlated (r = 0.76; p < 0.01. Our results emphasize that lengthy ankle muscle co-activation and COP path in gait initiation differentiate yoga practitioners among physically active subjects.

[Subjective Gait Stability in the Elderly].

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Hirsch, Theresa; Lampe, Jasmin; Michalk, Katrin; Röder, Lotte; Munsch, Karoline; Marquardt, Jonas

2017-07-10

It can be assumed that the feeling of gait stability or gait instability in the elderly may be independent of a possible fear of falling or a history of falling when walking. Up to now, there has been a lack of spatiotemporal gait parameters for older people who subjectively feel secure when walking. The aim of the study is to analyse the distribution of various gait parameters for older people who subjectively feel secure when walking. In a cross-sectional study, the gait parameters stride time, step time, stride length, step length, double support, single support, and walking speed were measured using a Vicon three-dimensional motion capture system (Plug-In Gait Lower-Body Marker Set) in 31 healthy people aged 65 years and older (mean age 72 ± 3.54 years) who subjectively feel secure when walking. There was a homogeneous distribution in the gait parameters examined, with no abnormalities. The mean values have a low variance with narrow confidence intervals. This study provides evidence that people who subjectively feel secure when walking demonstrate similarly objective gait parameters..

Gait analysis in a pre- and post-ischemic stroke biomedical pig model.

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Duberstein, Kylee Jo; Platt, Simon R; Holmes, Shannon P; Dove, C Robert; Howerth, Elizabeth W; Kent, Marc; Stice, Steven L; Hill, William D; Hess, David C; West, Franklin D

2014-02-10

Severity of neural injury including stroke in human patients, as well as recovery from injury, can be assessed through changes in gait patterns of affected individuals. Similar quantification of motor function deficits has been measured in rodent animal models of such injuries. However, due to differences in fundamental structure of human and rodent brains, there is a need to develop a large animal model to facilitate treatment development for neurological conditions. Porcine brain structure is similar to that of humans, and therefore the pig may make a more clinically relevant animal model. The current study was undertaken to determine key gait characteristics in normal biomedical miniature pigs and dynamic changes that occur post-neural injury in a porcine middle cerebral artery (MCA) occlusion ischemic stroke model. Yucatan miniature pigs were trained to walk through a semi-circular track and were recorded with high speed cameras to detect changes in key gait parameters. Analysis of normal pigs showed overall symmetry in hindlimb swing and stance times, forelimb stance time, along with step length, step velocity, and maximum hoof height on both fore and hindlimbs. A subset of pigs were again recorded at 7, 5 and 3 days prior to MCA occlusion and then at 1, 3, 5, 7, 14 and 30 days following surgery. MRI analysis showed that MCA occlusion resulted in significant infarction. Gait analysis indicated that stroke resulted in notable asymmetries in both temporal and spatial variables. Pigs exhibited lower maximum front hoof height on the paretic side, as well as shorter swing time and longer stance time on the paretic hindlimb. These results support that gait analysis of stroke injury is a highly sensitive detection method for changes in gait parameters in pig. Copyright © 2013 Elsevier Inc. All rights reserved.

Eight-Week Remote Monitoring Using a Freely Worn Device Reveals Unstable Gait Patterns in Older Fallers.

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Brodie, Matthew A; Lord, Stephen R; Coppens, Milou J; Annegarn, Janneke; Delbaere, Kim

2015-11-01

Develop algorithms to detect gait impairments remotely using data from freely worn devices during long-term monitoring. Identify statistical models that describe how gait performances are distributed over several weeks. Determine the data window required to reliably assess an increased propensity for falling. 1085 days of walking data were collected from eighteen independent-living older people (mean age 83 years) using a freely worn pendant sensor (housing a triaxial accelerometer and pressure sensor). Statistical distributions from several accelerometer-derived gait features (encompassing quantity, exposure, intensity, and quality) were compared for those with and without a history of falling. Participants completed more short walks relative to long walks, as approximated by a power law. Walks less than 13.1 s comprised 50% of exposure to walking-related falls. Daily-life cadence was bimodal and step-time variability followed a log-normal distribution. Fallers took significantly fewer steps per walk and had relatively more exposure from short walks and greater mode of step-time variability. Using a freely worn device and wavelet-based analysis tools allowed long-term monitoring of walks greater than or equal to three steps. In older people, short walks constitute a large proportion of exposure to falls. To identify fallers, mode of variability may be a better measure of central tendency than mean of variability. A week's monitoring is sufficient to reliably assess the long-term propensity for falling. Statistical distributions of gait performances provide a reference for future wearable device development and research into the complex relationships between daily-life walking patterns, morbidity, and falls.

Gait variability and basal ganglia disorders: stride-to-stride variations of gait cycle timing in Parkinson's disease and Huntington's disease

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Hausdorff, J. M.; Cudkowicz, M. E.; Firtion, R.; Wei, J. Y.; Goldberger, A. L.

1998-01-01

The basal ganglia are thought to play an important role in regulating motor programs involved in gait and in the fluidity and sequencing of movement. We postulated that the ability to maintain a steady gait, with low stride-to-stride variability of gait cycle timing and its subphases, would be diminished with both Parkinson's disease (PD) and Huntington's disease (HD). To test this hypothesis, we obtained quantitative measures of stride-to-stride variability of gait cycle timing in subjects with PD (n = 15), HD (n = 20), and disease-free controls (n = 16). All measures of gait variability were significantly increased in PD and HD. In subjects with PD and HD, gait variability measures were two and three times that observed in control subjects, respectively. The degree of gait variability correlated with disease severity. In contrast, gait speed was significantly lower in PD, but not in HD, and average gait cycle duration and the time spent in many subphases of the gait cycle were similar in control subjects, HD subjects, and PD subjects. These findings are consistent with a differential control of gait variability, speed, and average gait cycle timing that may have implications for understanding the role of the basal ganglia in locomotor control and for quantitatively assessing gait in clinical settings.

Gait Disorders in Parkinson's Disease: Assessment and Management

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Pei-Hao Chen

2013-12-01

Full Text Available Gait disorder, a major cause of morbidity in the elderly population, is one of the cardinal features of Parkinson's disease. Owing to the characteristics of these gaits varying widely from festination to freezing of gait, analysis can be hardly identified in the clinical setting. Instrumented gait analysis has been widely used in a traditional gait laboratory. Recently, wireless monitoring systems have become highly informative by allowing long-term data collection in a variety of environments outside the labs. The quantitative analysis of gait patterns is probably the first step to a successful management of an individual patient. The presence of abnormal gait usually indicates advanced stages of disease and is often associated with cognitive impairment, falls, and injuries. Besides pharmacological and surgical treatments, parkinsonian gait can benefit from a variety of interventions. Assistive devices prevent patients from falls, and cueing strategies help them decrease episodes of freezing. Therefore, a multidisciplinary team approach to the optimal management is essential for an elderly patient with Parkinson's disease.

Detecting Gait Asymmetry with Wearable Accelerometers

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2015-03-18

by overuse. Common overuse injuries include stress fractures , tendinitis, bursitis, fasciitis, and medial tibial stress syndrome (shin splints) [11...magnitude feature values for subject 1 are shown in (a), before and after repetitive stress injury. Magnitude and pattern features are plotted in...Dudziñski, A. Lees, M. Lake, and M. Wychowañski, “Adjustments in gait symmetry with walking speed in trans-femoral and trans- tibial amputees,” Gait

Does robot-assisted gait training ameliorate gait abnormalities in multiple sclerosis? A pilot randomized-control trial.

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Straudi, S; Benedetti, M G; Venturini, E; Manca, M; Foti, C; Basaglia, N

2013-01-01

Gait disorders are common in multiple sclerosis (MS) and lead to a progressive reduction of function and quality of life. Test the effects of robot-assisted gait rehabilitation in MS subjects through a pilot randomized-controlled study. We enrolled MS subjects with Expanded Disability Status Scale scores within 4.5-6.5. The experimental group received 12 robot-assisted gait training sessions over 6 weeks. The control group received the same amount of conventional physiotherapy. Outcomes measures were both biomechanical assessment of gait, including kinematics and spatio-temporal parameters, and clinical test of walking endurance (six-minute walk test) and mobility (Up and Go Test). 16 subjects (n = 8 experimental group, n = 8 control group) were included in the final analysis. At baseline the two groups were similar in all variables, except for step length. Data showed walking endurance, as well as spatio-temporal gait parameters improvements after robot-assisted gait training. Pelvic antiversion and reduced hip extension during terminal stance ameliorated after aforementioned intervention. Robot-assisted gait training seems to be effective in increasing walking competency in MS subjects. Moreover, it could be helpful in restoring the kinematic of the hip and pelvis.

Gait Complexity and Regularity Are Differently Modulated by Treadmill Walking in Parkinson's Disease and Healthy Population

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Thibault Warlop

2018-02-01

Full Text Available Variability raises considerable interest as a promising and sensitive marker of dysfunction in physiology, in particular in neurosciences. Both internally (e.g., pathology and/or externally (e.g., environment generated perturbations and the neuro-mechanical responses to them contribute to the fluctuating dynamics of locomotion. Defective internal gait control in Parkinson's disease (PD, resulting in typical timing gait disorders, is characterized by the breakdown of the temporal organization of stride duration variability. Influence of external cue on gait pattern could be detrimental or advantageous depending on situations (healthy or pathological gait pattern, respectively. As well as being an interesting rehabilitative approach in PD, treadmills are usually implemented in laboratory settings to perform instrumented gait analysis including gait variability assessment. However, possibly acting as an external pacemaker, treadmill could modulate the temporal organization of gait variability of PD patients which could invalidate any gait variability assessment. This study aimed to investigate the immediate influence of treadmill walking (TW on the temporal organization of stride duration variability in PD and healthy population. Here, we analyzed the gait pattern of 20 PD patients and 15 healthy age-matched subjects walking on overground and on a motorized-treadmill (randomized order at a self-selected speed. The temporal organization and regularity of time series of walking were assessed on 512 consecutive strides and assessed by the application of non-linear mathematical methods (i.e., the detrended fluctuation analysis and power spectral density; and sample entropy, for the temporal organization and regularity of gait variability, respectively. A more temporally organized and regular gait pattern seems to emerge from TW in PD while no influence was observed on healthy gait pattern. Treadmill could afford the necessary framework to regulate gait

Gait alterations can reduce the risk of edge loading.

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Wesseling, Mariska; Meyer, Christophe; De Groote, Friedl; Corten, Kristoff; Simon, Jean-Pierre; Desloovere, Kaat; Jonkers, Ilse

2016-06-01

Following metal-on-metal hip arthroplasty, edge loading (i.e., loading near the edge of a prosthesis cup) can increase wear and lead to early revision. The position and coverage angle of the prosthesis cup influence the risk of edge loading. This study investigates the effect of altered gait patterns, more specific hip, and pelvis kinematics, on the orientation of hip contact force and the consequent risk of antero-superior edge loading using muscle driven simulations of gait. With a cup orientation of 25° anteversion and 50° inclination and a coverage angle of 168°, many gait patterns presented risk of edge loading. Specifically at terminal double support, 189 out of 405 gait patterns indicated a risk of edge loading. At this time instant, the high hip contact forces and the proximity of the hip contact force to the edge of the cup indicated the likelihood of the occurrence of edge loading. Although the cup position contributed most to edge loading, altering kinematics considerably influenced the risk of edge loading. Increased hip abduction, resulting in decreasing hip contact force magnitude, and decreased hip extension, resulting in decreased risk on edge loading, are gait strategies that could prevent edge loading. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1069-1076, 2016. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Spatio-temporal gait disorder and gait fatigue index in a six-minute walk test in women with fibromyalgia.

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Heredia-Jimenez, Jose; Latorre-Roman, Pedro; Santos-Campos, Maria; Orantes-Gonzalez, Eva; Soto-Hermoso, Victor M

2016-03-01

Gait disorders in fibromyalgia patients affect several gait parameters and different muscle recruitment patterns. The aim of this study was to assess the gait differences observed during a six-minute walk test between fibromyalgia patients and healthy controls. Forty-eight women with fibromyalgia and 15 healthy women were evaluated. Fibromyalgia patients met the American College of Rheumatology criteria for fibromyalgia selected of an ambulatory care. Both patients and controls had a negative history of musculoskeletal disease, neurological disorders, and gait abnormalities. The 15 controls were healthy women matched to the patients in age, height and body weight. Spatio-temporal gait variables and the rate of perceived exertion during the six-minute walk test (all subjects) and Fibromyalgia Impact Questionnaire (fibromyalgia subjects) were evaluated. All walking sets on the GaitRITE were collected and the gait variables were selected at three stages during the six-minute walk test: two sets at the beginning, two sets at 3 min and two sets at the end of the test. In addition, the Fibromyalgia Impact Questionnaire was used for the fibromyalgia patients. Fibromyalgia patients showed a significant decrease in all spatio-temporal gait variables at each of the three stages and had a lower walk distance covered in the six-minute walk test and higher rate of perceived exertion. No correlations were found between the Fibromyalgia Impact Questionnaire and gait variables. The fibromyalgia and control subjects showed lower gait fatigue indices between the middle and last stages. Gait analysis during a six-minute walk test is a good tool to assess the fatigue and physical symptoms of patients with fibromyalgia. Copyright © 2016 Elsevier Ltd. All rights reserved.

Diagnostic gait pattern of a patient with longstanding left femoral nerve palsy: a case report.

LENUS (Irish Health Repository)

Burke, Neil G

2010-12-01

The gait pattern of a 35-year-old man with longstanding, left femoral nerve palsy was assessed using 3-dimensional kinematic and kinetic analysis. Stability of his left knee in stance was achieved by manipulating the external moments of the limb so that the ground reaction force passes in front of the knee joint. This compensatory mechanism of locking the knee in extension is reliant on the posterior capsular structures. The patient was managed conservatively and continued to walk without aids.

Entrainment to a real time fractal visual stimulus modulates fractal gait dynamics.

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Rhea, Christopher K; Kiefer, Adam W; D'Andrea, Susan E; Warren, William H; Aaron, Roy K

2014-08-01

Fractal patterns characterize healthy biological systems and are considered to reflect the ability of the system to adapt to varying environmental conditions. Previous research has shown that fractal patterns in gait are altered following natural aging or disease, and this has potential negative consequences for gait adaptability that can lead to increased risk of injury. However, the flexibility of a healthy neurological system to exhibit different fractal patterns in gait has yet to be explored, and this is a necessary step toward understanding human locomotor control. Fifteen participants walked for 15min on a treadmill, either in the absence of a visual stimulus or while they attempted to couple the timing of their gait with a visual metronome that exhibited a persistent fractal pattern (contained long-range correlations) or a random pattern (contained no long-range correlations). The stride-to-stride intervals of the participants were recorded via analog foot pressure switches and submitted to detrended fluctuation analysis (DFA) to determine if the fractal patterns during the visual metronome conditions differed from the baseline (no metronome) condition. DFA α in the baseline condition was 0.77±0.09. The fractal patterns in the stride-to-stride intervals were significantly altered when walking to the fractal metronome (DFA α=0.87±0.06) and to the random metronome (DFA α=0.61±0.10) (both p<.05 when compared to the baseline condition), indicating that a global change in gait dynamics was observed. A variety of strategies were identified at the local level with a cross-correlation analysis, indicating that local behavior did not account for the consistent global changes. Collectively, the results show that a gait dynamics can be shifted in a prescribed manner using a visual stimulus and the shift appears to be a global phenomenon. Copyright © 2014 Elsevier B.V. All rights reserved.

A mechanical energy analysis of gait initiation

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Miller, C. A.; Verstraete, M. C.

1999-01-01

The analysis of gait initiation (the transient state between standing and walking) is an important diagnostic tool to study pathologic gait and to evaluate prosthetic devices. While past studies have quantified mechanical energy of the body during steady-state gait, to date no one has computed the mechanical energy of the body during gait initiation. In this study, gait initiation in seven normal male subjects was studied using a mechanical energy analysis to compute total body energy. The data showed three separate states: quiet standing, gait initiation, and steady-state gait. During gait initiation, the trends in the energy data for the individual segments were similar to those seen during steady-state gait (and in Winter DA, Quanbury AO, Reimer GD. Analysis of instantaneous energy of normal gait. J Biochem 1976;9:253-257), but diminished in amplitude. However, these amplitudes increased to those seen in steady-state during the gait initiation event (GIE), with the greatest increase occurring in the second step due to the push-off of the foundation leg. The baseline level of mechanical energy was due to the potential energy of the individual segments, while the cyclic nature of the data was indicative of the kinetic energy of the particular leg in swing phase during that step. The data presented showed differences in energy trends during gait initiation from those of steady state, thereby demonstrating the importance of this event in the study of locomotion.

Day-to-day reliability of gait characteristics in rats

DEFF Research Database (Denmark)

Raffalt, Peter Christian; Nielsen, Louise R; Madsen, Stefan

2018-01-01

day-to-day reliability of the gait pattern parameters observed in rats during treadmill walking. The results of the present study may serve as a reference material that can help future intervention studies on rat gait characteristics both with respect to the selection of outcome measures...

The gait standard deviation, a single measure of kinematic variability.

Science.gov (United States)

Sangeux, Morgan; Passmore, Elyse; Graham, H Kerr; Tirosh, Oren

2016-05-01

Measurement of gait kinematic variability provides relevant clinical information in certain conditions affecting the neuromotor control of movement. In this article, we present a measure of overall gait kinematic variability, GaitSD, based on combination of waveforms' standard deviation. The waveform standard deviation is the common numerator in established indices of variability such as Kadaba's coefficient of multiple correlation or Winter's waveform coefficient of variation. Gait data were collected on typically developing children aged 6-17 years. Large number of strides was captured for each child, average 45 (SD: 11) for kinematics and 19 (SD: 5) for kinetics. We used a bootstrap procedure to determine the precision of GaitSD as a function of the number of strides processed. We compared the within-subject, stride-to-stride, variability with the, between-subject, variability of the normative pattern. Finally, we investigated the correlation between age and gait kinematic, kinetic and spatio-temporal variability. In typically developing children, the relative precision of GaitSD was 10% as soon as 6 strides were captured. As a comparison, spatio-temporal parameters required 30 strides to reach the same relative precision. The ratio stride-to-stride divided by normative pattern variability was smaller in kinematic variables (the smallest for pelvic tilt, 28%) than in kinetic and spatio-temporal variables (the largest for normalised stride length, 95%). GaitSD had a strong, negative correlation with age. We show that gait consistency may stabilise only at, or after, skeletal maturity. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparing electro- and mechano-myographic muscle activation patterns in self-paced pediatric gait.

Science.gov (United States)

Plewa, Katherine; Samadani, Ali; Chau, Tom

2017-10-01

Electromyography (EMG) is the standard modality for measuring muscle activity. However, the convenience and availability of low-cost accelerometer-based wearables makes mechanomyography (MMG) an increasingly attractive alternative modality for clinical applications. Literature to date has demonstrated a strong association between EMG and MMG temporal alignment in isometric and isokinetic contractions. However, the EMG-MMG relationship has not been studied in gait. In this study, the concurrence of EMG- and MMG-detected contractions in the tibialis anterior, lateral gastrocnemius, vastus lateralis, and biceps femoris muscles were investigated in children during self-paced gait. Furthermore, the distribution of signal power over the gait cycle was statistically compared between EMG-MMG modalities. With EMG as the reference, muscular contractions were detected based on MMG with balanced accuracies between 88 and 94% for all muscles except the gastrocnemius. MMG signal power differed from that of EMG during certain phases of the gait cycle in all muscles except the biceps femoris. These timing and power distribution differences between the two modalities may in part be related to muscle fascicle length changes that are unique to muscle motion during gait. Our findings suggest that the relationship between EMG and MMG appears to be more complex during gait than in isometric and isokinetic contractions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Spatiotemporal organization of alpha-motoneuron activity in the human spinal cord during different gaits and gait transitions.

Science.gov (United States)

Ivanenko, Y P; Cappellini, G; Poppele, R E; Lacquaniti, F

2008-06-01

Here we studied the spatiotemporal organization of motoneuron (MN) activity during different human gaits. We recorded the electromyographic (EMG) activity patterns in 32 ipsilateral limb and trunk muscles from normal subjects while running and walking on a treadmill (3-12 km/h). In addition, we recorded backward walking and skipping, a distinct human gait that comprises the features of both walking and running. We mapped the recorded EMG activity patterns onto the spinal cord in approximate rostrocaudal locations of the MN pools. The activation of MNs tends to occur in bursts and be segregated by spinal segment in a gait-specific manner. In particular, sacral and cervical activation timings were clearly gait-dependent. Swing-related activity constituted an appreciable fraction (> 30%) of the total MN activity of leg muscles. Locomoting at non-preferred speeds (running and walking at 5 and 9 km/h, respectively) showed clear differences relative to preferred speeds. Running at low speeds was characterized by wider sacral activation. Walking at high non-preferred speeds was accompanied by an 'atypical' locus of activation in the upper lumbar spinal cord during late stance and by a drastically increased activation of lumbosacral segments. The latter findings suggest that the optimal speed of gait transitions may be related to an optimal intensity of the total MN activity, in addition to other factors previously described. The results overall support the idea of flexibility and adaptability of spatiotemporal activity in the spinal circuitry with constraints on the temporal functional connectivity of hypothetical pulsatile burst generators.

Extraction of human gait signatures: an inverse kinematic approach using Groebner basis theory applied to gait cycle analysis

Science.gov (United States)

Barki, Anum; Kendricks, Kimberly; Tuttle, Ronald F.; Bunker, David J.; Borel, Christoph C.

2013-05-01

This research highlights the results obtained from applying the method of inverse kinematics, using Groebner basis theory, to the human gait cycle to extract and identify lower extremity gait signatures. The increased threat from suicide bombers and the force protection issues of today have motivated a team at Air Force Institute of Technology (AFIT) to research pattern recognition in the human gait cycle. The purpose of this research is to identify gait signatures of human subjects and distinguish between subjects carrying a load to those subjects without a load. These signatures were investigated via a model of the lower extremities based on motion capture observations, in particular, foot placement and the joint angles for subjects affected by carrying extra load on the body. The human gait cycle was captured and analyzed using a developed toolkit consisting of an inverse kinematic motion model of the lower extremity and a graphical user interface. Hip, knee, and ankle angles were analyzed to identify gait angle variance and range of motion. Female subjects exhibited the most knee angle variance and produced a proportional correlation between knee flexion and load carriage.

Gait characteristics of hemiparetic stroke survivors in Osun State ...

African Journals Online (AJOL)

Stroke is one of the leading causes of severe handicap. Deficiencies in walking may present significant challenges to mobility, resulting in abnormal and inefficient gait patterns in stroke survivors. This study compared the gait characteristics of hemiparetic stroke survivors and those of healthy individuals and determined the ...

A Comprehensive Study on Cross-View Gait Based Human Identification with Deep CNNs.

Science.gov (United States)

Wu, Zifeng; Huang, Yongzhen; Wang, Liang; Wang, Xiaogang; Tan, Tieniu

2017-02-01

This paper studies an approach to gait based human identification via similarity learning by deep convolutional neural networks (CNNs). With a pretty small group of labeled multi-view human walking videos, we can train deep networks to recognize the most discriminative changes of gait patterns which suggest the change of human identity. To the best of our knowledge, this is the first work based on deep CNNs for gait recognition in the literature. Here, we provide an extensive empirical evaluation in terms of various scenarios, namely, cross-view and cross-walking-condition, with different preprocessing approaches and network architectures. The method is first evaluated on the challenging CASIA-B dataset in terms of cross-view gait recognition. Experimental results show that it outperforms the previous state-of-the-art methods by a significant margin. In particular, our method shows advantages when the cross-view angle is large, i.e., no less than 36 degree. And the average recognition rate can reach 94 percent, much better than the previous best result (less than 65 percent). The method is further evaluated on the OU-ISIR gait dataset to test its generalization ability to larger data. OU-ISIR is currently the largest dataset available in the literature for gait recognition, with 4,007 subjects. On this dataset, the average accuracy of our method under identical view conditions is above 98 percent, and the one for cross-view scenarios is above 91 percent. Finally, the method also performs the best on the USF gait dataset, whose gait sequences are imaged in a real outdoor scene. These results show great potential of this method for practical applications.

Sensory feedback plays a significant role in generating walking gait and in gait transition in salamanders: A simulation study

Directory of Open Access Journals (Sweden)

Nalin eHarischandra

2011-11-01

Full Text Available Here, we use a three-dimensional, neuro-musculo-mechanical model of a salamander with realistic physical parameters in order to investigate the role of sensory feedback in gait generation and transition. Activation of limb and axial muscles were driven by neural output patterns obtained from a central pattern generator (CPG which is composed of simulated spiking neurons with adaptation. The CPG consists of a body CPG and four limb CPGs that are interconnected via synapses both ipsilateraly and contralaterally. We use the model both with and without sensory modulation and for different combinations of ipsilateral and contralateral coupling between the limb CPGs. We found that the proprioceptive sensory inputs are essential in obtaining a coordinated walking gait. The sensory feedback includes the signals coming from the stretch receptor like intraspinal neurons located in the girdle regions and the limb stretch receptors residing in the hip and scapula regions of the salamander. On the other hand, coordinated motor output patterns for the trotting gait were obtainable without the sensory inputs. We found that the gait transition from walking to trotting can be induced by increased activity of the descending drive coming from the mesencephalic locomotor region (MLR and is helped by the sensory inputs at the hip and scapula regions detecting the late stance phase. More neurophysiological experiments are required to identify the precise type of mechanoreceptors in the salamander and the neural mechanisms mediating the sensory modulation.

Plantar Pressure During Gait in Pregnant Women.

Science.gov (United States)

Bertuit, Jeanne; Leyh, Clara; Rooze, Marcel; Feipel, Véronique

2016-11-01

During pregnancy, physical and hormonal modifications occur. Morphologic alterations of the feet are found. These observations can induce alterations in plantar pressure. This study sought to investigate plantar pressures during gait in the last 4 months of pregnancy and in the postpartum period. A comparison with nulliparous women was conducted to investigate plantar pressure modifications during pregnancy. Fifty-eight women in the last 4 months of pregnancy, nine postpartum women, and 23 healthy nonpregnant women (control group) performed gait trials on an electronic walkway at preferred speeds. The results for the three groups were compared using analysis of variance. During pregnancy, peak pressure and contact area decreased for the forefoot and rearfoot. These parameters increased significantly for the midfoot. The gait strategy seemed to be lateralization of gait with an increased contact area of the lateral midfoot and both reduced pressure and a later peak time on the medial forefoot. In the postpartum group, footprint parameters were modified compared with the pregnant group, indicating a trend toward partial return to control values, although differences persisted between the postpartum and control groups. Pregnant women had altered plantar pressures during gait. These findings could define a specific pattern of gait footprints in late pregnancy because plantar pressures had characteristics that could maintain a stable and safe gait.

Effect of walking on sand on gait kinematics in individuals with multiple sclerosis.

Science.gov (United States)

van den Berg, Maayken E L; Barr, Christopher J; McLoughlin, James V; Crotty, Maria

2017-08-01

Walking in the real-world involves negotiating challenging or uneven surfaces, including sand. This can be challenging for people with Multiple Sclerosis (PWMS) due to motor deficits affecting the lower extremities. The study objective was to characterise kinematic gait adaptations made by PWMS when walking on sand and describe any immediate post-adaptation effects. 17 PWMS (mean age 51.4 ± 5.5, Disease Steps 2.4 ± 1.0), and 14 age-and gender matched healthy adults (HA) took part in a case-control study. 3D gait analysis was conducted using an eight-camera Vicon motion capture system. Each participant completed walking trials over level ground (baseline), sand (gait adaptation response), and again level ground (post-adaptation). Spatiotemporal data and kinematic data for the hip knee and ankle were recorded. At baseline PWMS showed significantly less total lower limb flexion (pgait pattern to near baseline levels, in a manner similar to but with values not equalling HA. Further work is required to determine whether this mode of walking has potential to act as a gait retraining strategy to increase flexion of the lower limb. Copyright © 2017 Elsevier B.V. All rights reserved.

Analysis and Classification of Stride Patterns Associated with Children Development Using Gait Signal Dynamics Parameters and Ensemble Learning Algorithms

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Meihong Wu

2016-01-01

Full Text Available Measuring stride variability and dynamics in children is useful for the quantitative study of gait maturation and neuromotor development in childhood and adolescence. In this paper, we computed the sample entropy (SampEn and average stride interval (ASI parameters to quantify the stride series of 50 gender-matched children participants in three age groups. We also normalized the SampEn and ASI values by leg length and body mass for each participant, respectively. Results show that the original and normalized SampEn values consistently decrease over the significance level of the Mann-Whitney U test (p<0.01 in children of 3–14 years old, which indicates the stride irregularity has been significantly ameliorated with the body growth. The original and normalized ASI values are also significantly changing when comparing between any two groups of young (aged 3–5 years, middle (aged 6–8 years, and elder (aged 10–14 years children. Such results suggest that healthy children may better modulate their gait cadence rhythm with the development of their musculoskeletal and neurological systems. In addition, the AdaBoost.M2 and Bagging algorithms were used to effectively distinguish the children’s gait patterns. These ensemble learning algorithms both provided excellent gait classification results in terms of overall accuracy (≥90%, recall (≥0.8, and precision (≥0.8077.

Capability of 2 gait measures for detecting response to gait training in stroke survivors: Gait Assessment and Intervention Tool and the Tinetti Gait Scale.

Science.gov (United States)

Zimbelman, Janice; Daly, Janis J; Roenigk, Kristen L; Butler, Kristi; Burdsall, Richard; Holcomb, John P

2012-01-01

To characterize the performance of 2 observational gait measures, the Tinetti Gait Scale (TGS) and the Gait Assessment and Intervention Tool (G.A.I.T.), in identifying improvement in gait in response to gait training. In secondary analysis from a larger study of multimodal gait training for stroke survivors, we measured gait at pre-, mid-, and posttreatment according to G.A.I.T. and TGS, assessing their capability to capture recovery of coordinated gait components. Large medical center. Cohort of stroke survivors (N=44) greater than 6 months after stroke. All subjects received 48 sessions of a multimodal gait-training protocol. Treatment consisted of 1.5 hours per session, 4 sessions per week for 12 weeks, receiving these 3 treatment aspects: (1) coordination exercise, (2) body weight-supported treadmill training, and (3) overground gait training, with 46% of subjects receiving functional electrical stimulation. All subjects were evaluated with the G.A.I.T. and TGS before and after completing the 48-session intervention. An additional evaluation was performed at midtreatment (after session 24). For the total subject sample, there were significant pre-/post-, pre-/mid-, and mid-/posttreatment gains for both the G.A.I.T. and the TGS. According to the G.A.I.T., 40 subjects (91%) showed improved scores, 2 (4%) no change, and 2 (4%) a worsening score. According to the TGS, only 26 subjects (59%) showed improved scores, 16 (36%) no change, and 1 (2%) a worsening score. For 1 treatment group of chronic stroke survivors, the TGS failed to identify a significant treatment response to gait training, whereas the G.A.I.T. measure was successful. The G.A.I.T. is more sensitive than the TGS for individual patients and group treatment response in identifying recovery of volitional control of gait components in response to gait training. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Real-Time Knee Adduction Moment Feedback for Gait Retraining Through Visual and Tactile Displays

KAUST Repository

Wheeler, Jason W.; Shull, Pete B.; Besier, Thor F.

2011-01-01

The external knee adduction moment (KAM) measured during gait is an indicator of tibiofemoral joint osteoarthritis progression and various strategies have been proposed to lower it. Gait retraining has been shown to be an effective, noninvasive approach for lowering the KAM. We present a new gait retraining approach in which the KAM is fed back to subjects in real-time during ambulation. A study was conducted in which 16 healthy subjects learned to alter gait patterns to lower the KAM through visual or tactile (vibration) feedback. Participants converged on a comfortable gait in just a few minutes by using the feedback to iterate on various kinematic modifications. All subjects adopted altered gait patterns with lower KAM compared with normal ambulation (average reduction of 20.7%). Tactile and visual feedbacks were equally effective for real-time training, although subjects using tactile feedback took longer to converge on an acceptable gait. This study shows that real-time feedback of the KAM can greatly increase the effectiveness and efficiency of subject-specific gait retraining compared with conventional methods. © 2011 American Society of Mechanical Engineers.

Kinematic trajectories while walking within the Lokomat robotic gait-orthosis.

Science.gov (United States)

Hidler, Joseph; Wisman, Wessel; Neckel, Nathan

2008-12-01

Background One of the most popular robot assisted rehabilitation devices used is the Lokomat. Unfortunately, not much is known about the behaviors exhibited by subjects in this device. The goal of this study was to evaluate the kinematic patterns of individuals walking inside the Lokomat compared to those demonstrated on a treadmill. Methods Six healthy subjects walked on a treadmill and inside the Lokomat while the motions of the subject and Lokomat were tracked. Joint angles and linear motion were determined for Lokomat and treadmill walking. We also evaluated the variability of the patterns, and the repeatability of measuring techniques. Findings The overall kinematics in the Lokomat are similar to those on a treadmill, however there was significantly more hip and ankle extension, and greater hip and ankle range of motion in the Lokomat (P<0.05). Additionally, the linear movement of joints was reduced in the Lokomat. Subjects tested on repeated sessions presented consistent kinematics, demonstrating the ability to consistently setup and test subjects. Interpretation The reduced degrees of freedom in the Lokomat are believed to be the reason for the specific kinematic differences. We found that despite being firmly attached to the device there was still subject movement relative to the Lokomat. This led to variability in the patterns, where subjects altered their gait pattern from step to step. These results are clinically important as a variable step pattern has been shown to be a more effective gait training strategy than one which forces the same kinematic pattern in successive steps.

Gait variability: methods, modeling and meaning

Directory of Open Access Journals (Sweden)

Hausdorff Jeffrey M

2005-07-01

Full Text Available Abstract The study of gait variability, the stride-to-stride fluctuations in walking, offers a complementary way of quantifying locomotion and its changes with aging and disease as well as a means of monitoring the effects of therapeutic interventions and rehabilitation. Previous work has suggested that measures of gait variability may be more closely related to falls, a serious consequence of many gait disorders, than are measures based on the mean values of other walking parameters. The Current JNER series presents nine reports on the results of recent investigations into gait variability. One novel method for collecting unconstrained, ambulatory data is reviewed, and a primer on analysis methods is presented along with a heuristic approach to summarizing variability measures. In addition, the first studies of gait variability in animal models of neurodegenerative disease are described, as is a mathematical model of human walking that characterizes certain complex (multifractal features of the motor control's pattern generator. Another investigation demonstrates that, whereas both healthy older controls and patients with a higher-level gait disorder walk more slowly in reduced lighting, only the latter's stride variability increases. Studies of the effects of dual tasks suggest that the regulation of the stride-to-stride fluctuations in stride width and stride time may be influenced by attention loading and may require cognitive input. Finally, a report of gait variability in over 500 subjects, probably the largest study of this kind, suggests how step width variability may relate to fall risk. Together, these studies provide new insights into the factors that regulate the stride-to-stride fluctuations in walking and pave the way for expanded research into the control of gait and the practical application of measures of gait variability in the clinical setting.

Kinematic analysis quantifies gait abnormalities associated with lameness in broiler chickens and identifies evolutionary gait differences.

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Gina Caplen

Full Text Available This is the first time that gait characteristics of broiler (meat chickens have been compared with their progenitor, jungle fowl, and the first kinematic study to report a link between broiler gait parameters and defined lameness scores. A commercial motion-capturing system recorded three-dimensional temporospatial information during walking. The hypothesis was that the gait characteristics of non-lame broilers (n = 10 would be intermediate to those of lame broilers (n = 12 and jungle fowl (n = 10, tested at two ages: immature and adult. Data analysed using multi-level models, to define an extensive range of baseline gait parameters, revealed inter-group similarities and differences. Natural selection is likely to have made jungle fowl walking gait highly efficient. Modern broiler chickens possess an unbalanced body conformation due to intense genetic selection for additional breast muscle (pectoral hypertrophy and whole body mass. Together with rapid growth, this promotes compensatory gait adaptations to minimise energy expenditure and triggers high lameness prevalence within commercial flocks; lameness creating further disruption to the gait cycle and being an important welfare issue. Clear differences were observed between the two lines (short stance phase, little double-support, low leg lift, and little back displacement in adult jungle fowl; much double-support, high leg lift, and substantial vertical back movement in sound broilers presumably related to mass and body conformation. Similarities included stride length and duration. Additional modifications were also identified in lame broilers (short stride length and duration, substantial lateral back movement, reduced velocity presumably linked to musculo-skeletal abnormalities. Reduced walking velocity suggests an attempt to minimise skeletal stress and/or discomfort, while a shorter stride length and time, together with longer stance and double-support phases, are associated

Gait Analysis Study of Runner Using Force Plate

Directory of Open Access Journals (Sweden)

Flaviana Catherine

2017-02-01

Full Text Available Humans do regular physical activities such as running. Gait is forward  propulsion of the human body using lower extremities as a thrust. Humans gait pattern is characterized by their limbs movement in terms of velocity, ground reaction force, work, kinetic energy and potential energy cycle . Human gait analysis is used to assess, to plan, and to deliver the treatment for individuals based on the conditions that affect their ability to move. Gait analysis is commonly used in running sport to improve the efficiency of athletes in running and to identify problems related to their posture or movement. The aim of this research is to do running gait analysis study of human, using force plate which equipped by track board. The benefit of this study is to provide information, ideas and new perspectives about running and its prevention over an injury. The main method that will be discussed in this study is system design of gait analysis with specific setting, hardware and software, in order to acquire data(s.

Gait parameter control timing with dynamic manual contact or visual cues

Science.gov (United States)

Shi, Peter; Werner, William

2016-01-01

We investigated the timing of gait parameter changes (stride length, peak toe velocity, and double-, single-support, and complete step duration) to control gait speed. Eleven healthy participants adjusted their gait speed on a treadmill to maintain a constant distance between them and a fore-aft oscillating cue (a place on a conveyor belt surface). The experimental design balanced conditions of cue modality (vision: eyes-open; manual contact: eyes-closed while touching the cue); treadmill speed (0.2, 0.4, 0.85, and 1.3 m/s); and cue motion (none, ±10 cm at 0.09, 0.11, and 0.18 Hz). Correlation analyses revealed a number of temporal relationships between gait parameters and cue speed. The results suggest that neural control ranged from feedforward to feedback. Specifically, step length preceded cue velocity during double-support duration suggesting anticipatory control. Peak toe velocity nearly coincided with its most-correlated cue velocity during single-support duration. The toe-off concluding step and double-support durations followed their most-correlated cue velocity, suggesting feedback control. Cue-tracking accuracy and cue velocity correlations with timing parameters were higher with the manual contact cue than visual cue. The cue/gait timing relationships generalized across cue modalities, albeit with greater delays of step-cycle events relative to manual contact cue velocity. We conclude that individual kinematic parameters of gait are controlled to achieve a desired velocity at different specific times during the gait cycle. The overall timing pattern of instantaneous cue velocities associated with different gait parameters is conserved across cues that afford different performance accuracies. This timing pattern may be temporally shifted to optimize control. Different cue/gait parameter latencies in our nonadaptation paradigm provide general-case evidence of the independent control of gait parameters previously demonstrated in gait adaptation paradigms

Gait parameter control timing with dynamic manual contact or visual cues.

Science.gov (United States)

Rabin, Ely; Shi, Peter; Werner, William

2016-06-01

We investigated the timing of gait parameter changes (stride length, peak toe velocity, and double-, single-support, and complete step duration) to control gait speed. Eleven healthy participants adjusted their gait speed on a treadmill to maintain a constant distance between them and a fore-aft oscillating cue (a place on a conveyor belt surface). The experimental design balanced conditions of cue modality (vision: eyes-open; manual contact: eyes-closed while touching the cue); treadmill speed (0.2, 0.4, 0.85, and 1.3 m/s); and cue motion (none, ±10 cm at 0.09, 0.11, and 0.18 Hz). Correlation analyses revealed a number of temporal relationships between gait parameters and cue speed. The results suggest that neural control ranged from feedforward to feedback. Specifically, step length preceded cue velocity during double-support duration suggesting anticipatory control. Peak toe velocity nearly coincided with its most-correlated cue velocity during single-support duration. The toe-off concluding step and double-support durations followed their most-correlated cue velocity, suggesting feedback control. Cue-tracking accuracy and cue velocity correlations with timing parameters were higher with the manual contact cue than visual cue. The cue/gait timing relationships generalized across cue modalities, albeit with greater delays of step-cycle events relative to manual contact cue velocity. We conclude that individual kinematic parameters of gait are controlled to achieve a desired velocity at different specific times during the gait cycle. The overall timing pattern of instantaneous cue velocities associated with different gait parameters is conserved across cues that afford different performance accuracies. This timing pattern may be temporally shifted to optimize control. Different cue/gait parameter latencies in our nonadaptation paradigm provide general-case evidence of the independent control of gait parameters previously demonstrated in gait adaptation paradigms

Apolipoprotein E4 Allele and Gait Performance in Mild Cognitive Impairment: Results From the Gait and Brain Study.

Science.gov (United States)

Sakurai, Ryota; Montero-Odasso, Manuel

2017-11-09

The apolipoprotein E polymorphism ε4 allele (ApoE4) and gait impairment are both known risk factors for developing cognitive decline and dementia. However, it is unclear the interrelationship between these factors, particularly among older adults with mild cognitive impairment (MCI) who are considered as prodromal for Alzheimer's disease. This study aimed to determine whether ApoE4 carrier individuals with MCI may experience greater impairment in gait performance. Fifty-six older adults with MCI from the "Gait and Brain Study" who were identified as either ApoE4 carriers (n = 20) or non-ApoE4 carriers (n = 36) with 1 year of follow-up were included. Gait variability, the main outcome variable, was assessed as stride time variability with an electronic walkway. Additional gait variables and cognitive performance (mini-mental state examination [MMSE] and Montreal Cognitive Assessment [MoCA]) were also recorded. Covariates included age, sex, education level, body mass index, and number of comorbidities. Baseline characteristics were similar for both groups. Repeated measures analysis of covariance showed that gait stride time and stride length variabilities significantly increased in ApoE4 carriers but was maintained in the non-ApoE4 carriers. Similarly, ApoE4 carriers showed greater decrease in MMSE score at follow-up. In this sample of older adults with MCI, the presence of at least one copy of ApoE4 was associated with the development of both increased gait variability and cognitive decline during 1 year of follow-up. ApoE4 genotype might be considered as a potential mediator of decline in mobility function in MCI; future studies with larger samples are needed to confirm our preliminary findings. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Similarity-based pattern analysis and recognition

CERN Document Server

Pelillo, Marcello

2013-01-01

This accessible text/reference presents a coherent overview of the emerging field of non-Euclidean similarity learning. The book presents a broad range of perspectives on similarity-based pattern analysis and recognition methods, from purely theoretical challenges to practical, real-world applications. The coverage includes both supervised and unsupervised learning paradigms, as well as generative and discriminative models. Topics and features: explores the origination and causes of non-Euclidean (dis)similarity measures, and how they influence the performance of traditional classification alg

Gait impairment in cervical spondylotic myelopathy: comparison with age- and gender-matched healthy controls.

LENUS (Irish Health Repository)

Malone, Ailish

2012-12-01

Gait impairment is a primary symptom of cervical spondylotic myelopathy (CSM); however, little is known about specific kinetic and kinematic gait parameters. The objectives of the study were: (1) to compare gait patterns of people with untreated CSM to those of age- and gender-matched healthy controls; (2) to examine the effect of gait speed on kinematic and kinetic parameters.

A Wearable Gait Phase Detection System Based on Force Myography Techniques

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Xianta Jiang

2018-04-01

Full Text Available (1 Background: Quantitative evaluation of gait parameters can provide useful information for constructing individuals’ gait profile, diagnosing gait abnormalities, and better planning of rehabilitation schemes to restore normal gait pattern. Objective determination of gait phases in a gait cycle is a key requirement in gait analysis applications; (2 Methods: In this study, the feasibility of using a force myography-based technique for a wearable gait phase detection system is explored. In this regard, a force myography band is developed and tested with nine participants walking on a treadmill. The collected force myography data are first examined sample-by-sample and classified into four phases using Linear Discriminant Analysis. The gait phase events are then detected from these classified samples using a set of supervisory rules; (3 Results: The results show that the force myography band can correctly detect more than 99.9% of gait phases with zero insertions and only four deletions over 12,965 gait phase segments. The average temporal error of gait phase detection is 55.2 ms, which translates into 2.1% error with respect to the corresponding labelled stride duration; (4 Conclusions: This proof-of-concept study demonstrates the feasibility of force myography techniques as viable solutions in developing wearable gait phase detection systems.

Gait Deviations in Children with Autism Spectrum Disorders: A Review

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Deirdre Kindregan

2015-01-01

Full Text Available In recent years, it has become clear that children with autism spectrum disorders (ASDs have difficulty with gross motor function and coordination, factors which influence gait. Knowledge of gait abnormalities may be useful for assessment and treatment planning. This paper reviews the literature assessing gait deviations in children with ASD. Five online databases were searched using keywords “gait” and “autism,” and 11 studies were found which examined gait in childhood ASD. Children with ASD tend to augment their walking stability with a reduced stride length, increased step width and therefore wider base of support, and increased time in the stance phase. Children with ASD have reduced range of motion at the ankle and knee during gait, with increased hip flexion. Decreased peak hip flexor and ankle plantar flexor moments in children with ASD may imply weakness around these joints, which is further exhibited by a reduction in ground reaction forces at toe-off in children with ASD. Children with ASD have altered gait patterns to healthy controls, widened base of support, and reduced range of motion. Several studies refer to cerebellar and basal ganglia involvement as the patterns described suggest alterations in those areas of the brain. Further research should compare children with ASD to other clinical groups to improve assessment and treatment planning.

Reflex control of robotic gait using human walking data.

Directory of Open Access Journals (Sweden)

Catherine A Macleod

Full Text Available Control of human walking is not thoroughly understood, which has implications in developing suitable strategies for the retraining of a functional gait following neurological injuries such as spinal cord injury (SCI. Bipedal robots allow us to investigate simple elements of the complex nervous system to quantify their contribution to motor control. RunBot is a bipedal robot which operates through reflexes without using central pattern generators or trajectory planning algorithms. Ground contact information from the feet is used to activate motors in the legs, generating a gait cycle visually similar to that of humans. Rather than developing a more complicated biologically realistic neural system to control the robot's stepping, we have instead further simplified our model by measuring the correlation between heel contact and leg muscle activity (EMG in human subjects during walking and from this data created filter functions transferring the sensory data into motor actions. Adaptive filtering was used to identify the unknown transfer functions which translate the contact information into muscle activation signals. Our results show a causal relationship between ground contact information from the heel and EMG, which allows us to create a minimal, linear, analogue control system for controlling walking. The derived transfer functions were applied to RunBot II as a proof of concept. The gait cycle produced was stable and controlled, which is a positive indication that the transfer functions have potential for use in the control of assistive devices for the retraining of an efficient and effective gait with potential applications in SCI rehabilitation.

Age-related decline of gait variability in children with attention-deficit/hyperactivity disorder: Support for the maturational delay hypothesis in gait.

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Manicolo, Olivia; Grob, Alexander; Lemola, Sakari; Hagmann-von Arx, Priska

2016-02-01

Previous findings showed a tendency toward higher gait variability in children with attention-deficit/hyperactivity disorder (ADHD) compared to controls. This study examined whether gait variability in children with ADHD eventually approaches normality with increasing age (delay hypothesis) or whether these gait alterations represent a persistent deviation from typical development (deviation hypothesis). This cross-sectional study compared 30 children with ADHD (25 boys; Mage=10 years 11 months, range 8-13 years; n=21 off medication, n=9 without medication) to 28 controls (25 boys; Mage=10 years 10 months, range 8-13 years). Gait parameters (i.e. velocity and variability in stride length and stride time) were assessed using an electronic walkway system (GAITRite) while children walked at their own pace. Children with ADHD walked with significantly higher variability in stride time compared to controls. Age was negatively associated with gait variability in children with ADHD such that children with higher age walked with lower variability, whereas in controls there was no such association. Children with ADHD displayed a less regular gait pattern than controls, indicated by their higher variability in stride time. The age-dependent decrease of gait variability in children with ADHD showed that gait performance became more regular with age and converged toward that of typically developing children. These results may reflect a maturational delay rather than a persistent deviation of gait regularity among children with ADHD compared to typically developing children. Copyright © 2015 Elsevier B.V. All rights reserved.

Self-similar pattern formation and continuous mechanics of self-similar systems

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A. V. Dyskin

2007-01-01

Full Text Available In many cases, the critical state of systems that reached the threshold is characterised by self-similar pattern formation. We produce an example of pattern formation of this kind – formation of self-similar distribution of interacting fractures. Their formation starts with the crack growth due to the action of stress fluctuations. It is shown that even when the fluctuations have zero average the cracks generated by them could grow far beyond the scale of stress fluctuations. Further development of the fracture system is controlled by crack interaction leading to the emergence of self-similar crack distributions. As a result, the medium with fractures becomes discontinuous at any scale. We develop a continuum fractal mechanics to model its physical behaviour. We introduce a continuous sequence of continua of increasing scales covering this range of scales. The continuum of each scale is specified by the representative averaging volume elements of the corresponding size. These elements determine the resolution of the continuum. Each continuum hides the cracks of scales smaller than the volume element size while larger fractures are modelled explicitly. Using the developed formalism we investigate the stability of self-similar crack distributions with respect to crack growth and show that while the self-similar distribution of isotropically oriented cracks is stable, the distribution of parallel cracks is not. For the isotropically oriented cracks scaling of permeability is determined. For permeable materials (rocks with self-similar crack distributions permeability scales as cube of crack radius. This property could be used for detecting this specific mechanism of formation of self-similar crack distributions.

Quantitative analysis of gait in the visually impaired.

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Nakamura, T

1997-05-01

In this comparative study concerning characteristics of independent walking by visually impaired persons, we used a motion analyser system to perform gait analysis of 15 late blind (age 36-54, mean 44.3 years), 15 congenitally blind (age 39-48, mean 43.8 years) and 15 sighted persons (age 40-50, mean 44.4 years) while walking a 10-m walkway. All subjects were male. Compared to the sighted, late blind and congenitally blind persons had a significantly slower walking speed, shorter stride length and longer time in the stance phase of gait. However, the relationships between gait parameters in the late and congenitally blind groups were maintained, as in the sighted group. In addition, the gait of the late blind showed a tendency to approximate the gait patterns of the congenitally blind as the duration of visual loss progressed. Based on these results we concluded that the gait of visually impaired persons, through its active use of non-visual sensory input, represents an attempt to adapt to various environmental conditions in order to maintain a more stable posture and to effect safe walking.

Gait recovery is not associated with changes in the temporal patterning of muscle activity during treadmill walking in patients with post-stroke hemiparesis.

NARCIS (Netherlands)

Otter, A.R. den; Geurts, A.C.H.; Mulder, T.; Duysens, J.E.J.

2006-01-01

OBJECTIVE: To establish whether functional recovery of gait in patients with post-stroke hemiparesis coincides with changes in the temporal patterning of lower extremity muscle activity and coactivity during treadmill walking. METHODS: Electromyographic (EMG) data from both legs, maximum walking

Gait recovery is not associated with changes in the temporal patterning of muscle activity during treadmill walking in patients with post-stroke hemiparesis

NARCIS (Netherlands)

Den Otter, AR; Mulder, T; Duysens, J

Objective: To establish whether functional recovery of gait in patients with post-stroke hemiparesis coincides with changes in the temporal patterning of lower extremity muscle activity and coactivity during treadmill walking. Methods: Electromyographic (EMG) data from both legs, maximum walking

Gait of dairy cows on floors with different slipperiness.

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Telezhenko, E; Magnusson, M; Bergsten, C

2017-08-01

This study assessed the slip resistance of different types of solid flooring in cattle housing using a range of technical tests and gait analysis. Dynamic and static coefficient of friction, skid resistance, and abrasiveness were tested on concrete flooring with a smooth finish, a grooved pattern, or a tamped pattern, acid-resistant mastic asphalt, soft rubber mats, and a worn slatted concrete floor. Coefficients of friction and skid resistance were tested under clean and slurry-soiled conditions. Linear kinematic variables were assessed in 40 cows with trackway measurements after the cows passed over the floors in a straight walk. All gait variables were assessed as deviations from those obtained on the slatted concrete floor, which was used as a baseline. The coefficient of friction tests divided the floors into 3 categories: concrete flooring, which had a low coefficient of friction (0.29-0.41); mastic asphalt flooring, which had medium values (0.38-0.45); and rubber mats, which had high values (0.49-0.57). The highest abrasion (g/10 m) was on the asphalt flooring (4.48), and the concrete flooring with a tamped pattern had significantly higher abrasiveness (2.77) than the other concrete floors (1.26-1.60). Lowest values on the skid-resistance tests (dry/wet) were for smooth concrete (79/35) and mastic asphalt (65/47), especially with a slurry layer on the surface. Gait analysis mainly differentiated floors with higher friction and abrasion by longer strides and better tracking. Step asymmetry was lower on floors with high skid-resistance values. The most secure cow gait, in almost every aspect, was observed on soft rubber mats. Relationships between gait variables and physical floor characteristics ranged from average to weak (partial correlations 0.54-0.16). Thus, none of the physical characteristics alone was informative enough to characterize slip resistance. With reference to gait analysis, the abrasiveness of the hard surfaces was more informative than the

Comparison of trunk activity during gait initiation and walking in humans.

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Jean-Charles Ceccato

Full Text Available To understand the role of trunk muscles in maintenance of dynamic postural equilibrium we investigate trunk movements during gait initiation and walking, performing trunk kinematics analysis, Erector spinae muscle (ES recordings and dynamic analysis. ES muscle expressed a metachronal descending pattern of activity during walking and gait initiation. In the frontal and horizontal planes, lateroflexion and rotation occur before in the upper trunk and after in the lower trunk. Comparison of ES muscle EMGs and trunk kinematics showed that trunk muscle activity precedes corresponding kinematics activity, indicating that the ES drive trunk movement during locomotion and thereby allowing a better pelvis mobilization. EMG data showed that ES activity anticipates propulsive phases in walking with a repetitive pattern, suggesting a programmed control by a central pattern generator. Our findings also suggest that the programs for gait initiation and walking overlap with the latter beginning before the first has ended.

Gait biometrics under spoofing attacks: an experimental investigation

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Hadid, Abdenour; Ghahramani, Mohammad; Kellokumpu, Vili; Feng, Xiaoyi; Bustard, John; Nixon, Mark

2015-11-01

Gait is a relatively biometric modality which has a precious advantage over other modalities, such as iris and voice, in that it can be easily captured from a distance. Although it has recently become a topic of great interest in biometric research, there has been little investigation into gait spoofing attacks where a person tries to imitate the clothing or walking style of someone else. We recently analyzed for the first time the effects of spoofing attacks on silhouette-based gait biometric systems and showed that it was indeed possible to spoof gait biometric systems by clothing impersonation and the deliberate selection of a target that has a similar build to the attacker. To gain deeper insight into the performance of current gait biometric systems under spoofing attacks, we provide a thorough investigation on how clothing can be used to spoof a target and evaluate the performance of two state-of-the-art recognition methods on a gait spoofing database recorded at the University of Southampton. Furthermore, we describe and evaluate an initial solution coping with gait spoofing attacks. The obtained results are very promising and point out interesting findings which can be used for future investigations.

Random walk-based similarity measure method for patterns in complex object

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Liu Shihu

2017-04-01

Full Text Available This paper discusses the similarity of the patterns in complex objects. The complex object is composed both of the attribute information of patterns and the relational information between patterns. Bearing in mind the specificity of complex object, a random walk-based similarity measurement method for patterns is constructed. In this method, the reachability of any two patterns with respect to the relational information is fully studied, and in the case of similarity of patterns with respect to the relational information can be calculated. On this bases, an integrated similarity measurement method is proposed, and algorithms 1 and 2 show the performed calculation procedure. One can find that this method makes full use of the attribute information and relational information. Finally, a synthetic example shows that our proposed similarity measurement method is validated.

Cognition and gait show a selective pattern of association dominated by phenotype in incident Parkinson’s disease

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Sue eLord

2014-10-01

Full Text Available Reports outlining the association between gait and cognition in Parkinson’s disease (PD are limited because of methodological issues and a bias towards studying advanced disease. This study examines the association between gait and cognition in 121 early PD who were characterized according to motor phenotype, and 184 healthy older adults. Quantitative gait was captured using a 7m GAITrite walkway whilst walking for two minutes under single task conditions and described by five domains (pace, rhythm, variability, asymmetry and postural control. Cognitive outcomes were summarized by six domains (attention, working memory, visual memory, executive function, visuospatial function and global cognition. Partial correlations and multivariate linear regression were used to determine independent associations for all participants and for PD tremor-dominant (TD and postural instability and gait disorder (PIGD phenotypes, controlling for age, sex, and premorbid intelligence using the National Adult Reading Test (NART. Cognitive and gait outcomes were significantly worse for PD. Gait, but not cognitive outcomes, were selectively worse for the PIGD phenotype. Significant associations emerged for two gait domains for controls (pace and postural control and four gait domains for PD (pace, rhythm, variability, and postural control.The strongest correlation was for pace and attention for PD and controls. Associations were not significant for participants with the TD phenotype. In early PD the cognitive correlates of gait are predominantly with fronto-executive functions, and are determined by the PIGD PD phenotype. These associations provide a basis for understanding the complex role of cognition in Parkinsonian gait.

A method to standardize gait and balance variables for gait velocity.

NARCIS (Netherlands)

Iersel, M.B. van; Olde Rikkert, M.G.M.; Borm, G.F.

2007-01-01

Many gait and balance variables depend on gait velocity, which seriously hinders the interpretation of gait and balance data derived from walks at different velocities. However, as far as we know there is no widely accepted method to correct for effects of gait velocity on other gait and balance

Towards automated human gait disease classification using phase space representation of intrinsic mode functions

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Pratiher, Sawon; Patra, Sayantani; Pratiher, Souvik

2017-06-01

A novel analytical methodology for segregating healthy and neurological disorders from gait patterns is proposed by employing a set of oscillating components called intrinsic mode functions (IMF's). These IMF's are generated by the Empirical Mode Decomposition of the gait time series and the Hilbert transformed analytic signal representation forms the complex plane trace of the elliptical shaped analytic IMFs. The area measure and the relative change in the centroid position of the polygon formed by the Convex Hull of these analytic IMF's are taken as the discriminative features. Classification accuracy of 79.31% with Ensemble learning based Adaboost classifier validates the adequacy of the proposed methodology for a computer aided diagnostic (CAD) system for gait pattern identification. Also, the efficacy of several potential biomarkers like Bandwidth of Amplitude Modulation and Frequency Modulation IMF's and it's Mean Frequency from the Fourier-Bessel expansion from each of these analytic IMF's has been discussed for its potency in diagnosis of gait pattern identification and classification.

Association between the gait pattern characteristics of older people and their two-step test scores.

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Kobayashi, Yoshiyuki; Ogata, Toru

2018-04-27

The Two-Step test is one of three official tests authorized by the Japanese Orthopedic Association to evaluate the risk of locomotive syndrome (a condition of reduced mobility caused by an impairment of the locomotive organs). It has been reported that the Two-Step test score has a good correlation with one's walking ability; however, its association with the gait pattern of older people during normal walking is still unknown. Therefore, this study aims to clarify the associations between the gait patterns of older people observed during normal walking and their Two-Step test scores. We analyzed the whole waveforms obtained from the lower-extremity joint angles and joint moments of 26 older people in various stages of locomotive syndrome using principal component analysis (PCA). The PCA was conducted using a 260 × 2424 input matrix constructed from the participants' time-normalized pelvic and right-lower-limb-joint angles along three axes (ten trials of 26 participants, 101 time points, 4 angles, 3 axes, and 2 variable types per trial). The Pearson product-moment correlation coefficient between the scores of the principal component vectors (PCVs) and the scores of the Two-Step test revealed that only one PCV (PCV 2) among the 61 obtained relevant PCVs is significantly related to the score of the Two-Step test. We therefore concluded that the joint angles and joint moments related to PCV 2-ankle plantar-flexion, ankle plantar-flexor moments during the late stance phase, ranges of motion and moments on the hip, knee, and ankle joints in the sagittal plane during the entire stance phase-are the motions associated with the Two-Step test.

Curve aligning approach for gait authentication based on a wearable accelerometer

International Nuclear Information System (INIS)

Sun, Hu; Yuao, Tao

2012-01-01

Gait authentication based on a wearable accelerometer is a novel biometric which can be used for identity identification, medical rehabilitation and early detection of neurological disorders. The method for matching gait patterns tells heavily on authentication performances. In this paper, curve aligning is introduced as a new method for matching gait patterns and it is compared with correlation and dynamic time warping (DTW). A support vector machine (SVM) is proposed to fuse pattern-matching methods in a decision level. Accelerations collected from ankles of 22 walking subjects are processed for authentications in our experiments. The fusion of curve aligning with backward–forward accelerations and DTW with vertical accelerations promotes authentication performances substantially and consistently. This fusion algorithm is tested repeatedly. Its mean and standard deviation of equal error rates are 0.794% and 0.696%, respectively, whereas among all presented non-fusion algorithms, the best one shows an EER of 3.03%. (paper)

A human quadrupedal gait following poliomyelitis: From the Dercum-Muybridge collaboration (1885).

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Lanska, Douglas J

2016-03-01

Beginning in the late 1870s, before the invention of movie cameras or projectors, pioneering English American photographer Eadweard Muybridge photographed iconic image sequences of people and animals in motion using arrays of sequentially triggered single-image cameras. In 1885, Philadelphia neurologist Francis Dercum initiated a collaborative relationship with Muybridge at the University of Pennsylvania to photograph sequential images of patients with various neurologic disorders of movement, including an acquired pathologic quadrupedal gait in a young boy that developed as a consequence of poliomyelitis. This pathologic human quadrupedal gait was compared with other quadrupedal gaits filmed by Muybridge, including a toddler girl and an adult woman crawling on hands and knees, an adult woman bear crawling on hands and feet, and a baboon walking. All of the human quadrupedal gaits were lateral sequence gaits, whereas the baboon's walking gait was a diagonal sequence gait. Modern studies have confirmed the nonpathologic quadrupedal gait sequences of humans and nonhuman primates. Despite Dercum's assertion to the contrary, the limb placement pattern of the boy with a pathologic quadrupedal gait after poliomyelitis was not the typical gait of a primate quadruped, but rather was the typical gait sequence for normal human developmental and volitional quadrupedal gaits. © 2016 American Academy of Neurology.

Balance control during gait initiation: State-of-the-art and research perspectives.

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Yiou, Eric; Caderby, Teddy; Delafontaine, Arnaud; Fourcade, Paul; Honeine, Jean-Louis

2017-11-18

It is well known that balance control is affected by aging, neurological and orthopedic conditions. Poor balance control during gait and postural maintenance are associated with disability, falls and increased mortality. Gait initiation - the transient period between the quiet standing posture and steady state walking - is a functional task that is classically used in the literature to investigate how the central nervous system (CNS) controls balance during a whole-body movement involving change in the base of support dimensions and center of mass progression. Understanding how the CNS in able-bodied subjects exerts this control during such a challenging task is a pre-requisite to identifying motor disorders in populations with specific impairments of the postural system. It may also provide clinicians with objective measures to assess the efficiency of rehabilitation programs and better target interventions according to individual impairments. The present review thus proposes a state-of-the-art analysis on: (1) the balance control mechanisms in play during gait initiation in able bodied subjects and in the case of some frail populations; and (2) the biomechanical parameters used in the literature to quantify dynamic stability during gait initiation. Balance control mechanisms reviewed in this article included anticipatory postural adjustments, stance leg stiffness, foot placement, lateral ankle strategy, swing foot strike pattern and vertical center of mass braking. Based on this review, the following viewpoints were put forward: (1) dynamic stability during gait initiation may share a principle of homeostatic regulation similar to most physiological variables, where separate mechanisms need to be coordinated to ensure stabilization of vital variables, and consequently; and (2) rehabilitation interventions which focus on separate or isolated components of posture, balance, or gait may limit the effectiveness of current clinical practices.

Assessment of spatio-temporal gait parameters from trunk accelerations during human walking

NARCIS (Netherlands)

Zijlstra, W; Hof, AL

2003-01-01

This paper studies the feasibility of an analysis of spatio-temporal gait parameters based upon accelerometry. To this purpose, acceleration patterns of the trunk and their relationships with spatio-temporal gait parameters were analysed in healthy subjects. Based on model predictions of the body's

Crouch gait patterns defined using k-means cluster analysis are related to underlying clinical pathology.

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Rozumalski, Adam; Schwartz, Michael H

2009-08-01

In this study a gait classification method was developed and applied to subjects with Cerebral palsy who walk with excessive knee flexion at initial contact. Sagittal plane gait data, simplified using the gait features method, is used as input into a k-means cluster analysis to determine homogeneous groups. Several clinical domains were explored to determine if the clusters are related to underlying pathology. These domains included age, joint range-of-motion, strength, selective motor control, and spasticity. Principal component analysis is used to determine one overall score for each of the multi-joint domains (strength, selective motor control, and spasticity). The current study shows that there are five clusters among children with excessive knee flexion at initial contact. These clusters were labeled, in order of increasing gait pathology: (1) mild crouch with mild equinus, (2) moderate crouch, (3) moderate crouch with anterior pelvic tilt, (4) moderate crouch with equinus, and (5) severe crouch. Further analysis showed that age, range-of-motion, strength, selective motor control, and spasticity were significantly different between the clusters (p<0.001). The general tendency was for the clinical domains to worsen as gait pathology increased. This new classification tool can be used to define homogeneous groups of subjects in crouch gait, which can help guide treatment decisions and outcomes assessment.

The effect of age and knee osteoarthritis on muscle activation patterns and knee joint biomechanics during dual belt treadmill gait.

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Rutherford, Derek; Baker, Matthew; Wong, Ivan; Stanish, William

2017-06-01

To compare a group of individuals with moderate medial compartment knee osteoarthritis (OA) to both an age-matched asymptomatic group of older adults and younger adults to determine whether differences in knee joint muscle activation patterns and joint biomechanics exist during gait between these three groups. 20 young adults, 20 older adults, and 40 individuals with moderate knee OA were recruited. Using standardized procedures, surface electromyograms were recorded from the vastus lateralis and medialis, rectus femoris and the medial and lateral hamstrings. All individuals walked on a dual belt instrumented treadmill while segment motions and ground reaction forces were recorded. Sagittal plane motion and net external sagittal and frontal plane moments were calculated. Discrete measures and principal component analyses extracted amplitude and temporal waveform features. Analysis of Variance models using Bonferroni corrections determined between and within group differences in these gait features (α=0.05). Individuals with knee OA have distinct biomechanics and muscle activation patterns when compared to age-matched asymptomatic adults and younger adults whereas differences between the young and older adults were few and included only measures of muscle activation amplitude. Copyright © 2017 Elsevier Ltd. All rights reserved.

Rotational gait patterns in children and adolescents following tension band plating of idiopathic genua valga.

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Farr, Sebastian; Kranzl, Andreas; Hahne, Julia; Ganger, Rudolf

2017-08-01

Literature suggests that children and adolescents with idiopathic genua valga present with considerable gait deviations in frontal and transverse planes, including altered frontal knee moments, reduced external knee rotation, and increased external hip rotation. This study aimed to evaluate gait parameters in these patients after surgical correction using tension band plating (TBP). We prospectively evaluated 24 consecutive, skeletally immature patients, who received full-length standing radiographs and three-dimensional gait analysis before and after correction, and compared the results observed to a group of 11 typically developing peers. Prior to TBP the cohort showed significantly decreased (worse) internal frontal knee moments compared to the control group. After axis correction the mean and maximum knee moments changed significantly into normalized knee moments (p gait. In addition, the effect of transverse plane changes on knee moments in patients with restored, straight limb axis was calculated. Hence, patients with restored alignment but persistence of decreased external knee rotation demonstrated significantly greater knee moments than those without rotational abnormalities (p = 0.001). This study found that frontal knee moments during gait normalized in children with idiopathic genua valga after surgery. However, decreased external knee rotation and increased external hip rotation during gait persisted in the study cohort. Despite radiological correction, decreased external rotation during gait was associated with increases in medial knee loading. Surgical correction for children with genua valga but normal knee moments may be detrimental, due to redistribution of dynamic knee loading into the opposite joint compartment. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1617-1624, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Analysis of Parallel and Transverse Visual Cues on the Gait of Individuals with Idiopathic Parkinson's Disease

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de Melo Roiz, Roberta; Azevedo Cacho, Enio Walker; Cliquet, Alberto, Jr.; Barasnevicius Quagliato, Elizabeth Maria Aparecida

2011-01-01

Idiopathic Parkinson's disease (IPD) has been defined as a chronic progressive neurological disorder with characteristics that generate changes in gait pattern. Several studies have reported that appropriate external influences, such as visual or auditory cues may improve the gait pattern of patients with IPD. Therefore, the objective of this…

Variability of Stepping during a Virtual Reality Paradigm in Parkinson's Disease Patients with and without Freezing of Gait.

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Moran Gilat

Full Text Available Freezing of gait is a common and debilitating symptom affecting many patients with advanced Parkinson's disease. Although the pathophysiology of freezing of gait is not fully understood, a number of observations regarding the pattern of gait in patients with this symptom have been made. Increased 'Stride Time Variability' has been one of the most robust of these features. In this study we sought to identify whether patients with freezing of gait demonstrated similar fluctuations in their stepping rhythm whilst performing a seated virtual reality gait task that has recently been used to demonstrate the neural correlate of the freezing phenomenon.Seventeen patients with freezing and eleven non-freezers performed the virtual reality task twice, once whilst 'On' their regular Parkinsonian medication and once in their practically defined 'Off' state.All patients displayed greater step time variability during their 'Off' state assessment compared to when medicated. Additionally, in the 'Off' state, patients with freezing of gait had greater step time variability compared to non-freezers. The five steps leading up to a freezing episode in the virtual reality environment showed a significant increase in step time variability although the final three steps preceding the freeze were not characterized by a progressive shortening of latency.The results of this study suggest that characteristic features of gait disturbance observed in patients with freezing of gait can also be demonstrated with a virtual reality paradigm. These findings suggest that virtual reality may offer the potential to further explore the freezing phenomenon in Parkinson's disease.

Gait adjustments in obstacle crossing, gait initiation and gait termination after a recent lower limb amputation

NARCIS (Netherlands)

Vrieling, Aline H.; van Keeken, Helco G.; Schoppen, Tanneke; Hof, At L.; Otten, Bert; Halbertsma, Jan P. K.; Postema, Klaas

Objective: To describe the adjustments in gait characteristics of obstacle crossing, gait initiation and gait termination that occur in subjects with a recent lower limb amputation during the rehabilitation process. Design: Prospective and descriptive study. Subjects: Fourteen subjects with a recent

Altered vision destabilizes gait in older persons.

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Helbostad, Jorunn L; Vereijken, Beatrix; Hesseberg, Karin; Sletvold, Olav

2009-08-01

This study assessed the effects of dim light and four experimentally induced changes in vision on gait speed and footfall and trunk parameters in older persons walking on level ground. Using a quasi-experimental design, gait characteristics were assessed in full light, dim light, and in dim light combined with manipulations resulting in reduced depth vision, double vision, blurred vision, and tunnel vision, respectively. A convenience sample of 24 home-dwelling older women and men (mean age 78.5 years, SD 3.4) with normal vision for their age and able to walk at least 10 m without assistance participated. Outcome measures were gait speed and spatial and temporal parameters of footfall and trunk acceleration, derived from an electronic gait mat and accelerometers. Dim light alone had no effect. Vision manipulations combined with dim light had effect on most footfall parameters but few trunk parameters. The largest effects were found regarding double and tunnel vision. Men increased and women decreased gait speed following manipulations (p=0.017), with gender differences also in stride velocity variability (p=0.017) and inter-stride medio-lateral trunk acceleration variability (p=0.014). Gender effects were related to differences in body height and physical functioning. Results indicate that visual problems lead to a more cautious and unstable gait pattern even under relatively simple conditions. This points to the importance of assessing vision in older persons and correcting visual impairments where possible.

Quantitative Gait Analysis in Patients with Huntington’s Disease

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Seon Jong Pyo

2017-09-01

Full Text Available Objective Gait disturbance is the main factor contributing to a negative impact on quality of life in patients with Huntington’s disease (HD. Understanding gait features in patients with HD is essential for planning a successful gait strategy. The aim of this study was to investigate temporospatial gait parameters in patients with HD compared with healthy controls. Methods We investigated 7 patients with HD. Diagnosis was confirmed by genetic analysis, and patients were evaluated with the Unified Huntington’s Disease Rating Scale (UHDRS. Gait features were assessed with a gait analyzer. We compared the results of patients with HD to those of 7 age- and sex-matched normal controls. Results Step length and stride length were decreased and base of support was increased in the HD group compared to the control group. In addition, coefficients of variability for step and stride length were increased in the HD group. The HD group showed slower walking velocity, an increased stance/swing phase in the gait cycle and a decreased proportion of single support time compared to the control group. Cadence did not differ significantly between groups. Among the UHDRS subscores, total motor score and total behavior score were positively correlated with step length, and total behavior score was positively correlated with walking velocity in patients with HD. Conclusion Increased variability in step and stride length, slower walking velocity, increased stance phase, and decreased swing phase and single support time with preserved cadence suggest that HD gait patterns are slow, ataxic and ineffective. This study suggests that quantitative gait analysis is needed to assess gait problems in HD.

Effects of obesity and chronic low back pain on gait

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Galli Manuela

2011-09-01

Full Text Available Abstract Background Obesity is often associated with low back pain (LBP. Despite empirical evidence that LBP induces gait abnormalities, there is a lack of quantitative analysis of the combined effect of obesity and LBP on gait. The aim of our study was to quantify the gait pattern of obese subjects with and without LBP and normal-mass controls by using Gait Analysis (GA, in order to investigate the cumulative effects of obesity and LBP on gait. Methods Eight obese females with chronic LBP (OLG; age: 40.5 ± 10.1 years; BMI: 42.39 ± 5.47 Kg/m2, 10 obese females (OG; age: 33.6 ± 5.2 years; BMI: 39.26 ± 2.39 Kg/m2 and 10 healthy female subjects (CG; age: 33.4 ± 9.6 years; BMI: 22.8 ± 3.2 Kg/m2, were enrolled in this study and assessed with video recording and GA. Results and Discussion OLG showed longer stance duration and shorter step length when compared to OG and CG. They also had a low pelvis and hip ROM on the frontal plane, a low knee flexion in the swing phase and knee range of motion, a low dorsiflexion in stance and swing as compared to OG. No statistically significant differences were found in ankle power generation at push-off between OLG and OG, which appeared lower if compared to CG. At hip level, both OLG and OG exhibited high power generation levels during stance, with OLG showing the highest values. Conclusions Our results demonstrated that the association of obesity and LBP affects more the gait pattern than obesity alone. OLG were in fact characterised by an altered knee and ankle strategy during gait as compared to OG and CG. These elements may help optimizing rehabilitation planning and treatment in these patients.

Design of a gait training device for control of pelvic obliquity.

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Pietrusinski, Maciej; Severini, Giacomo; Cajigas, Iahn; Mavroidis, Constantinos; Bonato, Paolo

2012-01-01

This paper presents the design and testing of a novel device for the control of pelvic obliquity during gait. The device, called the Robotic Gait Rehabilitation (RGR) Trainer, consists of a single actuator system designed to target secondary gait deviations, such as hip-hiking, affecting the movement of the pelvis. Secondary gait deviations affecting the pelvis are generated in response to primary gait deviations (e.g. limited knee flexion during the swing phase) in stroke survivors and contribute to the overall asymmetrical gait pattern often observed in these patients. The proposed device generates a force field able to affect the obliquity of the pelvis (i.e. the rotation of the pelvis around the anteroposterior axis) by using an impedance controlled single linear actuator acting on a hip orthosis. Tests showed that the RGR Trainer is able to induce changes in pelvic obliquity trajectories (hip-hiking) in healthy subjects. These results suggest that the RGR Trainer is suitable to test the hypothesis that has motivated our efforts toward developing the system, namely that addressing both primary and secondary gait deviations during robotic-assisted gait training may help promote a physiologically-sound gait behavior more effectively than when only primary deviations are addressed.

Kinematic Gait Changes Following Serial Casting and Bracing to Treat Toe Walking in a Child With Autism.

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Barkocy, Marybeth; Dexter, James; Petranovich, Colleen

2017-07-01

To evaluate the effectiveness of serial casting in a child with autism spectrum disorder (ASD) exhibiting a toe-walking gait pattern with equinus contractures. Although many children with ASD toe walk, little research on physical therapy interventions exists for this population. Serial casting has been validated for use in idiopathic toe walking to increase passive dorsiflexion and improve gait, but not for toe walking in children with ASD. Serial casting followed by ankle-foot orthosis use was implemented to treat a child with ASD who had an obligatory equinus gait pattern. Gait analysis supported improvements in kinematic, spatial, and temporal parameters of gait, and the child maintained a consistent heel-toe gait at 2-year follow-up. STATEMENT OF CONCLUSION AND RECOMMENDATIONS FOR CLINICAL PRACTICE:: Serial casting followed by ankle-foot orthosis use is a viable treatment option for toe walking in children with ASD.

GaitKeeper: A System for Measuring Canine Gait

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Cassim Ladha

2017-02-01

Full Text Available It is understood gait has the potential to be used as a window into neurodegenerative disorders, identify markers of subclinical pathology, inform diagnostic algorithms of disease progression and measure the efficacy of interventions. Dogs’ gaits are frequently assessed in a veterinary setting to detect signs of lameness. Despite this, a reliable, affordable and objective method to assess lameness in dogs is lacking. Most described canine lameness assessments are subjective, unvalidated and at high risk of bias. This means reliable, early detection of canine gait abnormalities is challenging, which may have detrimental implications for dogs’ welfare. In this paper, we draw from approaches and technologies used in human movement science and describe a system for objectively measuring temporal gait characteristics in dogs (step-time, swing-time, stance-time. Asymmetries and variabilities in these characteristics are of known clinical significance when assessing lameness but presently may only be assessed on coarse scales or under highly instrumented environments. The system consists an inertial measurement unit, containing a 3-axis accelerometer and gyroscope coupled with a standardized walking course. The measurement unit is attached to each leg of the dog under assessment before it is walked around the course. The data by the measurement unit is then processed to identify steps and subsequently, micro-gait characteristics. This method has been tested on a cohort of 19 healthy dogs of various breeds ranging in height from 34.2 cm to 84.9 cm. We report the system as capable of making precise step delineations with detections of initial and final contact times of foot-to-floor to a mean precision of 0.011 s and 0.048 s, respectively. Results are based on analysis of 12,678 foot falls and we report a sensitivity, positive predictive value and F-score of 0.81, 0.83 and 0.82 respectively. To investigate the effect of gait on system performance

Three-Dimensional Trunk and Lower Limbs Characteristics during Gait in Patients with Huntington's Disease

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Elzbieta Mirek

2017-10-01

Full Text Available Objective: A number of studies on gait disturbances have been conducted, however, no clear pattern of gait disorders was described. The aim of the study was to characterize the gait pattern in HD patients by conducting analysis of mean angular movement changes the lower limb joints and trunk (kinematics parameters.Methods: The study group consisted of 30 patients with HD (17 women and 13 men. The reference data include the results of 30 healthy subjects (17 women and 13 men. Registration of gait with the Vicon 250 system was performed using passive markers attached to specific anthropometric points directly on the skin, based on the Golem biomechanical model (Oxford Metrics Ltd.. The research group and the control group were tested once.Results: Statistically significant (p < 0.05 angular changes in gait cycle for HD patients were observed in: insufficient plantar flexion during Loading Response and Pre-swing phases; insufficient flexion of the knee joint during Initial Swing and Mid Swing phases; excessive flexion of the hip in Terminal Stance and Pre-swing phases and over-normative forward inclination of the trunk in all gait phases. It should be noted that the group of patients with HD obtained, for all the mean angular movement changes higher standard deviation.Conclusion: A characteristic gait disorder common to all patients with HD occurring throughout the whole duration of the gait cycle is a pathological anterior tilt of the trunk. The results will significantly contribute to programming physiotherapy for people with HD, aimed at stabilizing the trunk in a position of extension during gait.

Gait Selection and Transition of Passivity-Based Bipeds with Adaptable Ankle Stiffness

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Yan Huang

2012-10-01

Full Text Available Stable bipedal walking is one of the most important components of humanoid robot design, which can help us better understand natural human walking. In this paper, to study gait selection and gait transition of efficient bipedal walking, we proposed a dynamic bipedal walking model with an upper body, flat feet and compliant joints. The model can achieve stable cyclic motion with different walking gaits. The hip actuation and ankle stiffness behavior of the model are quite similar to those of human normal walking. In simulation, we studied the influence of hip actuation and ankle stiffness on walking performance of each gait. The effects of ankle stiffness on gait selection are also analyzed. Gait transition is realized by adjusting ankle stiffness during walking.

Assessment of test-retest reliability and internal consistency of the Wisconsin Gait Scale in hemiparetic post-stroke patients

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Guzik Agnieszka

2016-09-01

Full Text Available Introduction: A proper assessment of gait pattern is a significant aspect in planning the process of teaching gait in hemiparetic post-stroke patients. The Wisconsin Gait Scale (WGS is an observational tool for assessing post-stroke patients’ gait. The aim of the study was to assess test-retest reliability and internal consistency of the WGS and examine correlations between gait assessment made with the WGS and gait speed, Brunnström scale, Ashworth’s scale and the Barthel Index.

View-invariant gait recognition method by three-dimensional convolutional neural network

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Xing, Weiwei; Li, Ying; Zhang, Shunli

2018-01-01

Gait as an important biometric feature can identify a human at a long distance. View change is one of the most challenging factors for gait recognition. To address the cross view issues in gait recognition, we propose a view-invariant gait recognition method by three-dimensional (3-D) convolutional neural network. First, 3-D convolutional neural network (3DCNN) is introduced to learn view-invariant feature, which can capture the spatial information and temporal information simultaneously on normalized silhouette sequences. Second, a network training method based on cross-domain transfer learning is proposed to solve the problem of the limited gait training samples. We choose the C3D as the basic model, which is pretrained on the Sports-1M and then fine-tune C3D model to adapt gait recognition. In the recognition stage, we use the fine-tuned model to extract gait features and use Euclidean distance to measure the similarity of gait sequences. Sufficient experiments are carried out on the CASIA-B dataset and the experimental results demonstrate that our method outperforms many other methods.

Gait patterns after intraarticular treatment of patients with osteoarthritis of the Knee - Hyaluronan versus triamcinolone: a prospective, randomized, doubleblind, monocentric study

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Skwara A

2009-04-01

Full Text Available Abstract Objective Evaluation of gait performance and muscle activity patterns as well as clinical efficacy and safety after single intraarticular injection with hyaluronan compared with triamcinolone in patients with knee osteoarthritis. Materials and Methods This trial evaluated the influence of a single injection of hyaluronan or triamcinolone on gait pattern and muscle activity. For clinical evaluation a visual analogue scale for pain, Lequesne index, and Knee Society Score were used. Quality of life was assessed with the SF-36. Results The complete analysis was performed in 50 of 60 patients. 26 patients were treated with triamcinolone and 24 with hyaluronan. Hyaluronan treatment led to significant improvement of range of motion at hip and knee. Significant improvement could be either demonstrated for the pain scale, Lequesne and Knee Society score in both groups. Quality of life showed greater improvement in the triamcinolone group. Conclusion Single application of high-viscosity hyaluronan shows superior range of motion and pain reduction as well as improvement in clinical results. Even if there was a lack of significant differences compared to triamcinolone, this therapy classified as safe and effective in the short follow up.

Two-dimensional PCA-based human gait identification

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Chen, Jinyan; Wu, Rongteng

2012-11-01

It is very necessary to recognize person through visual surveillance automatically for public security reason. Human gait based identification focus on recognizing human by his walking video automatically using computer vision and image processing approaches. As a potential biometric measure, human gait identification has attracted more and more researchers. Current human gait identification methods can be divided into two categories: model-based methods and motion-based methods. In this paper a two-Dimensional Principal Component Analysis and temporal-space analysis based human gait identification method is proposed. Using background estimation and image subtraction we can get a binary images sequence from the surveillance video. By comparing the difference of two adjacent images in the gait images sequence, we can get a difference binary images sequence. Every binary difference image indicates the body moving mode during a person walking. We use the following steps to extract the temporal-space features from the difference binary images sequence: Projecting one difference image to Y axis or X axis we can get two vectors. Project every difference image in the difference binary images sequence to Y axis or X axis difference binary images sequence we can get two matrixes. These two matrixes indicate the styles of one walking. Then Two-Dimensional Principal Component Analysis(2DPCA) is used to transform these two matrixes to two vectors while at the same time keep the maximum separability. Finally the similarity of two human gait images is calculated by the Euclidean distance of the two vectors. The performance of our methods is illustrated using the CASIA Gait Database.

Neuromuscular adjustments of gait associated with unstable conditions

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Ivanenko, Y. P.; d'Avella, A.; Serrao, M.; Ranavolo, A.; Draicchio, F.; Cappellini, G.; Casali, C.; Lacquaniti, F.

2015-01-01

A compact description of coordinated muscle activity is provided by the factorization of electromyographic (EMG) signals. With the use of this approach, it has consistently been shown that multimuscle activity during human locomotion can be accounted for by four to five modules, each one comprised of a basic pattern timed at a different phase of gait cycle and the weighting coefficients of synergistic muscle activations. These modules are flexible, in so far as the timing of patterns and the amplitude of weightings can change as a function of gait speed and mode. Here we consider the adjustments of the locomotor modules related to unstable walking conditions. We compared three different conditions, i.e., locomotion of healthy subjects on slippery ground (SL) and on narrow beam (NB) and of cerebellar ataxic (CA) patients on normal ground. Motor modules were computed from the EMG signals of 12 muscles of the right lower limb using non-negative matrix factorization. The unstable gait of SL, NB, and CA showed significant changes compared with controls in the stride length, stride width, range of angular motion, and trunk oscillations. In most subjects of all three unstable conditions, >70% of the overall variation of EMG waveforms was accounted for by four modules that were characterized by a widening of muscle activity patterns. This suggests that the nervous system adopts the strategy of prolonging the duration of basic muscle activity patterns to cope with unstable conditions resulting from either slippery ground, reduced support surface, or pathology. PMID:26378199

A novel approach to gait synchronization and transition for reconfigurable walking platforms

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Shunsuke Nansai

2015-04-01

Full Text Available Legged robots based on one degree-of-freedom reconfigurable planar leg mechanisms, that are capable of generating multiple useful gaits, are highly desired due to the possibility of handling environments and tasks of high complexity while maintaining simple control schemes. An essential consideration in these reconfigurable legged robots is to attain stability in motion, at rest as well as while transforming from one configuration to another with the minimum number of legs as long as the full range of their walking patterns, resulting from the different gait cycles of their legs, is achieved. To this end, in this paper, we present a method for the generation of input joint trajectories to properly synchronize the movement of quadruped robots with reconfigurable legs. The approach is exemplified in a four-legged robot with reconfigurable Jansen legs capable of generating up to six useful different gait cycles. The proposed technique is validated through simulated results that show the platform׳s stability across its six feasible walking patterns and during gait transition phases, thus considerably extending the capabilities of the non-reconfigurable design.

Gait analysis in hip viscosupplementation for osteoarthritis: a case report

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L. Di Lorenzo

2013-10-01

Full Text Available Hip is a site very commonly affected by osteoarthritis and the intra-articular administration of hyaluronic acid in the management of osteoarthritic pain is increasingly used. However, the debate about its usefulness is still ongoing, as not all results of clinical trials confirm its effectiveness. In order to achieve the best outcome, clinical assessment and treatment choices should be based on subjective outcome, pathological and mechanical findings that should be integrated with qualitative analysis of human movement. After viscosupplementation, clinical trials often evaluate as endpoint subjective outcomes (i.e. pain visual analogic scale and static imaging such as radiographs and magnetic resonance imaging. In our clinical practice we use gait analysis as part of rehabilitation protocol to measure performance, enhancement and changes of several biomechanical factors. Taking advantage of available resources (BTS Bioengineering gait analysis Elite System we studied a patient’s gait after ultrasound guided hip injections for viscosupplementation. He showed an early clinical and biomechanical improvement during walking after a single intra articular injection of hyaluronic acid. Gait analysis parameters obtained suggest that the pre-treatment slower speed may be caused by antalgic walking patterns, the need for pain control and muscle weakness. After hip viscosupplementation, the joint displayed different temporal, kinetic and kinematic parameters associated with improved pain patterns.

Interrater reliability of videotaped observational gait-analysis assessments.

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Eastlack, M E; Arvidson, J; Snyder-Mackler, L; Danoff, J V; McGarvey, C L

1991-06-01

The purpose of this study was to determine the interrater reliability of videotaped observational gait-analysis (VOGA) assessments. Fifty-four licensed physical therapists with varying amounts of clinical experience served as raters. Three patients with rheumatoid arthritis who demonstrated an abnormal gait pattern served as subjects for the videotape. The raters analyzed each patient's most severely involved knee during the four subphases of stance for the kinematic variables of knee flexion and genu valgum. Raters were asked to determine whether these variables were inadequate, normal, or excessive. The temporospatial variables analyzed throughout the entire gait cycle were cadence, step length, stride length, stance time, and step width. Generalized kappa coefficients ranged from .11 to .52. Intraclass correlation coefficients (2,1) and (3,1) were slightly higher. Our results indicate that physical therapists' VOGA assessments are only slightly to moderately reliable and that improved interrater reliability of the assessments of physical therapists utilizing this technique is needed. Our data suggest that there is a need for greater standardization of gait-analysis training.

Variability of Stepping during a Virtual Reality Paradigm in Parkinson's Disease Patients with and without Freezing of Gait

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Gilat, Moran; Shine, James M.; Bolitho, Samuel J.; Matar, Elie; Kamsma, Yvo P. T.; Naismith, Sharon L.; Lewis, Simon J. G.

2013-01-01

Background: Freezing of gait is a common and debilitating symptom affecting many patients with advanced Parkinson's disease. Although the pathophysiology of freezing of gait is not fully understood, a number of observations regarding the pattern of gait in patients with this symptom have been made.

Gait performance is not influenced by working memory when walking at a self-selected pace.

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Grubaugh, Jordan; Rhea, Christopher K

2014-02-01

Gait performance exhibits patterns within the stride-to-stride variability that can be indexed using detrended fluctuation analysis (DFA). Previous work employing DFA has shown that gait patterns can be influenced by constraints, such as natural aging or disease, and they are informative regarding a person's functional ability. Many activities of daily living require concurrent performance in the cognitive and gait domains; specifically working memory is commonly engaged while walking, which is considered dual-tasking. It is unknown if taxing working memory while walking influences gait performance as assessed by DFA. This study used a dual-tasking paradigm to determine if performance decrements are observed in gait or working memory when performed concurrently. Healthy young participants (N = 16) performed a working memory task (automated operation span task) and a gait task (walking at a self-selected speed on a treadmill) in single- and dual-task conditions. A second dual-task condition (reading while walking) was included to control for visual attention, but also introduced a task that taxed working memory over the long term. All trials involving gait lasted at least 10 min. Performance in the working memory task was indexed using five dependent variables (absolute score, partial score, speed error, accuracy error, and math error), while gait performance was indexed by quantifying the mean, standard deviation, and DFA α of the stride interval time series. Two multivariate analyses of variance (one for gait and one for working memory) were used to examine performance in the single- and dual-task conditions. No differences were observed in any of the gait or working memory dependent variables as a function of task condition. The results suggest the locomotor system is adaptive enough to complete a working memory task without compromising gait performance when walking at a self-selected pace.

Secure and privacy enhanced gait authentication on smart phone.

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Hoang, Thang; Choi, Deokjai

2014-01-01

Smart environments established by the development of mobile technology have brought vast benefits to human being. However, authentication mechanisms on portable smart devices, particularly conventional biometric based approaches, still remain security and privacy concerns. These traditional systems are mostly based on pattern recognition and machine learning algorithms, wherein original biometric templates or extracted features are stored under unconcealed form for performing matching with a new biometric sample in the authentication phase. In this paper, we propose a novel gait based authentication using biometric cryptosystem to enhance the system security and user privacy on the smart phone. Extracted gait features are merely used to biometrically encrypt a cryptographic key which is acted as the authentication factor. Gait signals are acquired by using an inertial sensor named accelerometer in the mobile device and error correcting codes are adopted to deal with the natural variation of gait measurements. We evaluate our proposed system on a dataset consisting of gait samples of 34 volunteers. We achieved the lowest false acceptance rate (FAR) and false rejection rate (FRR) of 3.92% and 11.76%, respectively, in terms of key length of 50 bits.

Secure and Privacy Enhanced Gait Authentication on Smart Phone

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Thang Hoang

2014-01-01

Full Text Available Smart environments established by the development of mobile technology have brought vast benefits to human being. However, authentication mechanisms on portable smart devices, particularly conventional biometric based approaches, still remain security and privacy concerns. These traditional systems are mostly based on pattern recognition and machine learning algorithms, wherein original biometric templates or extracted features are stored under unconcealed form for performing matching with a new biometric sample in the authentication phase. In this paper, we propose a novel gait based authentication using biometric cryptosystem to enhance the system security and user privacy on the smart phone. Extracted gait features are merely used to biometrically encrypt a cryptographic key which is acted as the authentication factor. Gait signals are acquired by using an inertial sensor named accelerometer in the mobile device and error correcting codes are adopted to deal with the natural variation of gait measurements. We evaluate our proposed system on a dataset consisting of gait samples of 34 volunteers. We achieved the lowest false acceptance rate (FAR and false rejection rate (FRR of 3.92% and 11.76%, respectively, in terms of key length of 50 bits.

The Dominant-Subthalamic Nucleus Phenomenon in Bilateral Deep Brain Stimulation for Parkinson’s Disease: Evidence from a Gait Analysis Study

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Mario Giorgio Rizzone

2017-10-01

Full Text Available BackgroundIt has been suggested that parkinsonian [Parkinson’s disease (PD] patients might have a “dominant” (DOM subthalamic nucleus (STN, whose unilateral electrical stimulation [deep brain stimulation (DBS] could lead to an improvement in PD symptoms similar to bilateral STN-DBS.ObjectivesSince disability in PD patients is often related to gait problems, in this study, we wanted to investigate in a group of patients bilaterally implanted for STN-DBS: (1 if it was possible to identify a subgroup of subjects with a dominant STN; (2 in the case, if the unilateral stimulation of the dominant STN was capable to improve gait abnormalities, as assessed by instrumented multifactorial gait analysis, similarly to what observed with bilateral stimulation.MethodsWe studied 10 PD patients with bilateral STN-DBS. A clinical evaluation and a kinematic, kinetic, and electromyographic (EMG analysis of overground walking were performed—off medication—in four conditions: without stimulation, with bilateral stimulation, with unilateral right or left STN-DBS. Through a hierarchical agglomerative cluster analysis based on motor Unified Parkinson’s Disease Rating Scale scores, it was possible to separate patients into two groups, based on the presence (six patients, DOM group or absence (four patients, NDOM group of a dominant STN.ResultsIn the DOM group, both bilateral and unilateral stimulation of the dominant STN significantly increased gait speed, stride length, range of motion of lower limb joints, and peaks of moment and power at the ankle joint; moreover, the EMG activation pattern of distal leg muscles was improved. The unilateral stimulation of the non-dominant STN did not produce any significant effect. In the NDOM group, only bilateral stimulation determined a significant improvement of gait parameters.ConclusionIn the DOM group, the effect of unilateral stimulation of the dominant STN determined an improvement of gait parameters similar to

Three-Dimensional Trunk and Lower Limbs Characteristics during Gait in Patients with Huntington's Disease.

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Mirek, Elzbieta; Filip, Magdalena; Chwała, Wiesław; Banaszkiewicz, Krzysztof; Rudzinska-Bar, Monika; Szymura, Jadwiga; Pasiut, Szymon; Szczudlik, Andrzej

2017-01-01

Objective: A number of studies on gait disturbances have been conducted, however, no clear pattern of gait disorders was described. The aim of the study was to characterize the gait pattern in HD patients by conducting analysis of mean angular movement changes the lower limb joints and trunk (kinematics parameters). Methods: The study group consisted of 30 patients with HD (17 women and 13 men). The reference data include the results of 30 healthy subjects (17 women and 13 men). Registration of gait with the Vicon 250 system was performed using passive markers attached to specific anthropometric points directly on the skin, based on the Golem biomechanical model (Oxford Metrics Ltd.). The research group and the control group were tested once. Results: Statistically significant ( p patients were observed in: insufficient plantar flexion during Loading Response and Pre-swing phases; insufficient flexion of the knee joint during Initial Swing and Mid Swing phases; excessive flexion of the hip in Terminal Stance and Pre-swing phases and over-normative forward inclination of the trunk in all gait phases. It should be noted that the group of patients with HD obtained, for all the mean angular movement changes higher standard deviation. Conclusion: A characteristic gait disorder common to all patients with HD occurring throughout the whole duration of the gait cycle is a pathological anterior tilt of the trunk. The results will significantly contribute to programming physiotherapy for people with HD, aimed at stabilizing the trunk in a position of extension during gait.

Clinical implications of gait analysis in the rehabilitation of adult patients with "Prader-Willi" Syndrome: a cross-sectional comparative study ("Prader-Willi" Syndrome vs matched obese patients and healthy subjects

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Baccalaro Gabriele

2007-05-01

Full Text Available Abstract Background Being severely overweight is a distinctive clinical feature of Prader-Willi Syndrome (PWS. PWS is a complex multisystem disorder, representing the most common form of genetic obesity. The aim of this study was the analysis of the gait pattern of adult subjects with PWS by using three-Dimensional Gait Analysis. The results were compared with those obtained in a group of obese patients and in a group of healthy subjects. Methods Cross-sectional, comparative study: 19 patients with PWS (11 males and 8 females, age: 18–40 years, BMI: 29.3–50.3 kg/m2; 14 obese matched patients (5 males and 9 females, age: 18–40 years, BMI: 34.3–45.2 kg/m2; 20 healthy subjects (10 males and 10 females, age: 21–41 years, BMI: 19.3–25.4 kg/m2. Kinematic and kinetic parameters during walking were assessed by an optoelectronic system and two force platforms. Results PWS adult patients walked slower, had a shorter stride length, a lower cadence and a longer stance phase compared with both matched obese, and healthy subjects. Obese matched patients showed spatio-temporal parameters significantly different from healthy subjects. Furthermore, Range Of Motion (ROM at knee and ankle, and plantaflexor activity of PWS patients were significantly different between obese and healthy subjects. Obese subjects revealed kinematic and kinetic data similar to healthy subjects. Conclusion PWS subjects had a gait pattern significantly different from obese patients. Despite that, both groups had a similar BMI. We suggest that PWS gait abnormalities may be related to abnormalities in the development of motor skills in childhood, due to precocious obesity. A tailored rehabilitation program in early childhood of PWS patients could prevent gait pattern changes.

Treadmill training with partial body weight support and an electromechanical gait trainer for restoration of gait in subacute stroke patients: a randomized crossover study.

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Werner, C; Von Frankenberg, S; Treig, T; Konrad, M; Hesse, S

2002-12-01

The purpose of this study was to compare treadmill and electromechanical gait trainer therapy in subacute, nonambulatory stroke survivors. The gait trainer was designed to provide nonambulatory subjects the repetitive practice of a gait-like movement without overexerting therapists. This was a randomized, controlled study with a crossover design following an A-B-A versus a B-A-B pattern. A consisted of 2 weeks of gait trainer therapy, and B consisted of 2 weeks of treadmill therapy. Thirty nonambulatory hemiparetic patients, 4 to 12 weeks after stroke, were randomly assigned to 1 of the 2 groups receiving locomotor therapy every workday for 15 to 20 minutes for 6 weeks. Weekly gait ability (functional ambulation category [FAC]), gait velocity, and the required physical assistance during both kinds of locomotor therapy were the primary outcome measures, and other motor functions (Rivermead motor assessment score) and ankle spasticity (modified Ashworth score) were the secondary outcome measures. Follow-up occurred 6 months later. The groups did not differ at study onset with respect to the clinical characteristics and effector variables. During treatment, the FAC, gait velocity, and Rivermead scores improved in both groups, and ankle spasticity did not change. Median FAC level was 4 (3 to 4) in group A compared with 3 (2 to 3) in group B at the end of treatment (P=0.018), but the difference at 6-month follow up was not significant. The therapeutic effort was less on the gait trainer, with 1 instead of 2 therapists assisting the patient at study onset. All but seven patients preferred the gait trainer. The newly developed gait trainer was at least as effective as treadmill therapy with partial body weight support while requiring less input from the therapist. Further studies are warranted.

Muscle synergies and complexity of neuromuscular control during gait in cerebral palsy.

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Steele, Katherine M; Rozumalski, Adam; Schwartz, Michael H

2015-12-01

Individuals with cerebral palsy (CP) have impaired movement due to a brain injury near birth. Understanding how neuromuscular control is altered in CP can provide insight into pathological movement. We sought to determine if individuals with CP demonstrate reduced complexity of neuromuscular control during gait compared with unimpaired individuals and if changes in control are related to functional ability. Muscle synergies during gait were retrospectively analyzed for 633 individuals (age range 3.9-70y): 549 with CP (hemiplegia, n=122; diplegia, n=266; triplegia, n=73; quadriplegia, n=88) and 84 unimpaired individuals. Synergies were calculated using non-negative matrix factorization from surface electromyography collected during previous clinical gait analyses. Synergy complexity during gait was compared with diagnosis subtype, functional ability, and clinical examination measures. Fewer synergies were required to describe muscle activity during gait in individuals with CP compared with unimpaired individuals. Changes in synergies were related to functional impairment and clinical examination measures including selective motor control, strength, and spasticity. Individuals with CP use a simplified control strategy during gait compared with unimpaired individuals. These results were similar to synergies during walking among adult stroke survivors, suggesting similar neuromuscular control strategies between these clinical populations. © 2015 Mac Keith Press.

Assessment of changes in gait parameters and vertical ground reaction forces after total hip arthroplasty

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Bhargava P

2007-01-01

Full Text Available The principal objectives of arthroplasty are relief of pain and enhancement of range of motion. Currently, postoperative pain and functional capacity are assessed largely on the basis of subjective evaluation scores. Because of the lack of control inherent in this method it is often difficult to interpret data presented by different observers in the critical evaluation of surgical method, new components and modes of rehabilitation. Gait analysis is a rapid, simple and reliable method to assess functional outcome. This study was undertaken in an effort to evaluate the gait characteristics of patients who underwent arthroplasty, using an Ultraflex gait analyzer. Materials and Methods: The study was based on the assessment of gait and weight-bearing pattern of both hips in patients who underwent total hip replacement and its comparison with an age and sex-matched control group. Twenty subjects of total arthroplasty group having unilateral involvement, operated by posterior approach at our institution with a minimum six-month postoperative period were selected. Control group was age and sex-matched, randomly selected from the general population. Gait analysis was done using Ultraflex gait analyzer. Gait parameters and vertical ground reaction forces assessment was done by measuring the gait cycle properties, step time parameters and VGRF variables. Data of affected limb was compared with unaffected limb as well as control group to assess the weight-bearing pattern. Statistical analysis was done by′t′ test. Results: Frequency is reduced and gait cycle duration increased in total arthroplasty group as compared with control. Step time parameters including Step time, Stance time and Single support time are significantly reduced ( P value < .05 while Double support time and Single swing time are significantly increased ( P value < .05 in the THR group. Forces over each sensor are increased more on the unaffected limb of the THR group as compared to

An electromechanical gait trainer for restoration of gait in hemiparetic stroke patients: preliminary results.

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Hesse, S; Werner, C; Uhlenbrock, D; von Frankenberg, S; Bardeleben, A; Brandl-Hesse, B

2001-01-01

Modern concepts of gait rehabilitation after stroke favor a task-specific repetitive approach. In practice, the required physical effort of the therapists limits the realization of this approach. Therefore, a mechanized gait trainer enabling nonambulatory patients to have the repetitive practice of a gait-like movement without overstraining therapists was constructed. This preliminary study investigated whether an additional 4-week daily therapy on the gait trainer could improve gait ability in 14 chronic wheelchair-bound hemiparetic subjects. The 4 weeks of physiotherapy and gait-trainer therapy resulted in a relevant improvement of gait ability in all subjects. Velocity, cadence, and stride length improved significantly (p gait trainer seems feasible as an adjunctive tool in gait rehabilitation after stroke; further studies are needed.

Outcomes following kinesthetic feedback for gait training in a direct access environment: a case report on social wellness in relation to gait impairment.

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Blievernicht, Jessica; Sullivan, Kate; Erickson, Mark R

2012-05-01

The purpose of this case report was to describe the outcomes following the use of kinesthetic feedback as a primary intervention strategy for gait training. The plan of care for this 22-year-old female addressed the patient's social wellness goal of "walking more normally," using motor learning principles. At initial examination, the patient demonstrated asymmetries for gait kinematics between the left and right lower extremity (analyzed using video motion analysis), pattern of force distribution at the foot, and activation of specific lower extremity muscles (as measured by surface electromyography). Interventions for this patient consisted of neuromuscular and body awareness training, with an emphasis on kinesthetic feedback. Weekly sessions lasted 30-60 minutes over 4 weeks. The patient was prescribed a home program of walking 30-60 minutes three times/week at a comfortable pace while concentrating on gait correction through kinesthetic awareness of specific deviations. Following intervention, the patient's gait improved across all objective measures. She reported receiving positive comments from others regarding improved gait and a twofold increase in her walking confidence. Outcomes support a broadened scope of practice that incorporates previously unreported integration of a patient's social wellness goals into patient management.

Energy Expenditure of Trotting Gait Under Different Gait Parameters

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Chen, Xian-Bao; Gao, Feng

2017-07-01

Robots driven by batteries are clean, quiet, and can work indoors or in space. However, the battery endurance is a great problem. A new gait parameter design energy saving strategy to extend the working hours of the quadruped robot is proposed. A dynamic model of the robot is established to estimate and analyze the energy expenditures during trotting. Given a trotting speed, optimal stride frequency and stride length can minimize the energy expenditure. However, the relationship between the speed and the optimal gait parameters is nonlinear, which is difficult for practical application. Therefore, a simplified gait parameter design method for energy saving is proposed. A critical trotting speed of the quadruped robot is found and can be used to decide the gait parameters. When the robot is travelling lower than this speed, it is better to keep a constant stride length and change the cycle period. When the robot is travelling higher than this speed, it is better to keep a constant cycle period and change the stride length. Simulations and experiments on the quadruped robot show that by using the proposed gait parameter design approach, the energy expenditure can be reduced by about 54% compared with the 100 mm stride length under 500 mm/s speed. In general, an energy expenditure model based on the gait parameter of the quadruped robot is built and the trotting gait parameters design approach for energy saving is proposed.

Real-time feedback of dynamic foot pressure index for gait training of toe-walking children with spastic diplegia.

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Pu, Fang; Ren, Weiyan; Fan, Xiaoya; Chen, Wei; Li, Shuyu; Li, Deyu; Wang, Yu; Fan, Yubo

2017-09-01

The aim of this study was to determine whether and how real-time feedback of dynamic foot pressure index (DFPI) could be used to correct toe-walking gait in spastic diplegic children with dynamic equinus. Thirteen spastic diplegic children with dynamic equinus were asked to wear a monitoring device to record their ambulation during daily gait, conventional training gait, and feedback training gait. Parameters based on their DFPI and stride duration were compared among the three test conditions. The results with feedback training were significantly better for all DFPI parameters in comparison to patients' daily gait and showed significant improvements in DFPI for toe-walking gait and percentage of normal gait in comparison to conventional training methods. Moreover, stride duration under two training gaits was longer than patient's daily gait, but there was no significant difference between the two training gaits. Although the stride duration for the two training gaits was similar, gait training with real-time feedback of DFPI did produce noticeably superior results by increasing heel-loading impulse of toe-walking gait and percentage of normal gait in comparison to convention training methods. However, its effectiveness was still impacted by the motion limitations of diplegic children. Implications for Rehabilitation The DFPI-based gait training feedback system introduced in this study was shown to be more effective at toe-walking gait rehabilitation training over conventional training methods. The feedback system accomplished superior improvement in correcting toe-walking gait, but its effectiveness in an increasing heel-loading impulse in normal gait was still limited by the motion limitations of diplegic children. Stride duration of normal gait and toe-walking gait was similar under conventional and feedback gait training.

Walking patterns in Parkinson's disease with and without freezing of gait

NARCIS (Netherlands)

Nanhoe-Mahabier, W.; Snijders, A.H.; Delval, A.; Weerdesteijn, V.G.M.; Duysens, J.E.J.; Overeem, S.; Bloem, B.R.

2011-01-01

The pathophysiology underlying freezing of gait (FOG) in Parkinson's disease remains incompletely understood. Patients with FOG ("freezers") have a higher temporal variability and asymmetry of strides compared to patients without FOG ("non-freezers"). We aimed to extend this view, by assessing

Plasticity of spinal centers in spinal cord injury patients: new concepts for gait evaluation and training.

Science.gov (United States)

Scivoletto, Giorgio; Ivanenko, Yuri; Morganti, Barbara; Grasso, Renato; Zago, Mirka; Lacquaniti, Francesco; Ditunno, John; Molinari, Marco

2007-01-01

Recent data on spinal cord plasticity after spinal cord injury (SCI) were reviewed to analyze the influence of training on the neurophysiological organization of locomotor spinal circuits in SCI patients. In particular, the authors studied the relationship between central pattern generators (CPGs) and motor neuron pool activation during gait. An analysis of the relations between locomotor recovery and compensatory mechanisms focuses on the hierarchical organization of gait parameters and allows characterizing kinematic parameters that are highly stable during different gait conditions and in recovered gait after SCI. The importance of training characteristics and the use of robotic/automated devices in gait recovery is analyzed and discussed. The role of CPG in defining kinematic gait parameters is summarized, and spatio-temporal maps of EMG activity during gait are used to clarify the role of CPG plasticity in sustaining gait recovery.

IMU-Based Gait Recognition Using Convolutional Neural Networks and Multi-Sensor Fusion

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Omid Dehzangi

2017-11-01

Full Text Available The wide spread usage of wearable sensors such as in smart watches has provided continuous access to valuable user generated data such as human motion that could be used to identify an individual based on his/her motion patterns such as, gait. Several methods have been suggested to extract various heuristic and high-level features from gait motion data to identify discriminative gait signatures and distinguish the target individual from others. However, the manual and hand crafted feature extraction is error prone and subjective. Furthermore, the motion data collected from inertial sensors have complex structure and the detachment between manual feature extraction module and the predictive learning models might limit the generalization capabilities. In this paper, we propose a novel approach for human gait identification using time-frequency (TF expansion of human gait cycles in order to capture joint 2 dimensional (2D spectral and temporal patterns of gait cycles. Then, we design a deep convolutional neural network (DCNN learning to extract discriminative features from the 2D expanded gait cycles and jointly optimize the identification model and the spectro-temporal features in a discriminative fashion. We collect raw motion data from five inertial sensors placed at the chest, lower-back, right hand wrist, right knee, and right ankle of each human subject synchronously in order to investigate the impact of sensor location on the gait identification performance. We then present two methods for early (input level and late (decision score level multi-sensor fusion to improve the gait identification generalization performance. We specifically propose the minimum error score fusion (MESF method that discriminatively learns the linear fusion weights of individual DCNN scores at the decision level by minimizing the error rate on the training data in an iterative manner. 10 subjects participated in this study and hence, the problem is a 10-class

Guidelines for Assessment of Gait and Reference Values for Spatiotemporal Gait Parameters in Older Adults: The Biomathics and Canadian Gait Consortiums Initiative

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Olivier Beauchet

2017-08-01

Full Text Available Background: Gait disorders, a highly prevalent condition in older adults, are associated with several adverse health consequences. Gait analysis allows qualitative and quantitative assessments of gait that improves the understanding of mechanisms of gait disorders and the choice of interventions. This manuscript aims (1 to give consensus guidance for clinical and spatiotemporal gait analysis based on the recorded footfalls in older adults aged 65 years and over, and (2 to provide reference values for spatiotemporal gait parameters based on the recorded footfalls in healthy older adults free of cognitive impairment and multi-morbidities.Methods: International experts working in a network of two different consortiums (i.e., Biomathics and Canadian Gait Consortium participated in this initiative. First, they identified items of standardized information following the usual procedure of formulation of consensus findings. Second, they merged databases including spatiotemporal gait assessments with GAITRite® system and clinical information from the “Gait, cOgnitiOn & Decline” (GOOD initiative and the Generation 100 (Gen 100 study. Only healthy—free of cognitive impairment and multi-morbidities (i.e., ≤ 3 therapeutics taken daily—participants aged 65 and older were selected. Age, sex, body mass index, mean values, and coefficients of variation (CoV of gait parameters were used for the analyses.Results: Standardized systematic assessment of three categories of items, which were demographics and clinical information, and gait characteristics (clinical and spatiotemporal gait analysis based on the recorded footfalls, were selected for the proposed guidelines. Two complementary sets of items were distinguished: a minimal data set and a full data set. In addition, a total of 954 participants (mean age 72.8 ± 4.8 years, 45.8% women were recruited to establish the reference values. Performance of spatiotemporal gait parameters based on the recorded

Subtle abnormalities of gait detected early in vitamin B6 deficiency in aged and weanling rats with hind leg gait analysis.

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Schaeffer, M C; Cochary, E F; Sadowski, J A

1990-04-01

Motor abnormalities have been observed in every species made vitamin B6 deficient, and have been detected and quantified early in vitamin B6 deficiency in young adult female Long-Evans rats with hind leg gait analysis. Our objective was to determine if hind leg gait analysis could be used to detect vitamin B6 deficiency in weanling (3 weeks) and aged (23 months) Fischer 344 male rats. Rats (n = 10 per group) were fed: the control diet ad libitum (AL-CON); the control diet devoid of added pyridoxine hydrochloride (DEF); or the control diet pair-fed to DEF (PF-CON). At 10 weeks, plasma pyridoxal phosphate concentration confirmed deficiency in both age groups. Gait abnormalities were detected in the absence of gross motor disturbances in both aged and weanling DEF rats at 2-3 weeks. Width of step was significantly reduced (16%, p less than 0.003) in DEF aged rats compared to AL- and PF-CON. This pattern of response was similar to that reported previously in young adult rats. In weanling rats, pair feeding alone reduced mean width of step (+/- SEM) by 25% compared to ad libitum feeding (2.7 +/- 0.1 vs 3.6 +/- 0.1 cm for PF- vs AL-CON, respectively, p less than 0.05). In DEF weanling rats, width (3.0 +/- 0.1 cm) was increased compared to PF-CON (11%, p less than 0.05) but decreased compared to AL-CON (16%, p less than 0.05). Width of step was significantly altered early in B6 deficiency in rats of different ages and strains and in both sexes.(ABSTRACT TRUNCATED AT 250 WORDS)

Gait performance and foot pressure distribution during wearable robot-assisted gait in elderly adults.

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Lee, Su-Hyun; Lee, Hwang-Jae; Chang, Won Hyuk; Choi, Byung-Ok; Lee, Jusuk; Kim, Jeonghun; Ryu, Gyu-Ha; Kim, Yun-Hee

2017-11-28

A robotic exoskeleton device is an intelligent system designed to improve gait performance and quality of life for the wearer. Robotic technology has developed rapidly in recent years, and several robot-assisted gait devices were developed to enhance gait function and activities of daily living in elderly adults and patients with gait disorders. In this study, we investigated the effects of the Gait-enhancing Mechatronic System (GEMS), a new wearable robotic hip-assist device developed by Samsung Electronics Co, Ltd., Korea, on gait performance and foot pressure distribution in elderly adults. Thirty elderly adults who had no neurological or musculoskeletal abnormalities affecting gait participated in this study. A three-dimensional (3D) motion capture system, surface electromyography and the F-Scan system were used to collect data on spatiotemporal gait parameters, muscle activity and foot pressure distribution under three conditions: free gait without robot assistance (FG), robot-assisted gait with zero torque (RAG-Z) and robot-assisted gait (RAG). We found increased gait speed, cadence, stride length and single support time in the RAG condition. Reduced rectus femoris and medial gastrocnemius muscle activity throughout the terminal stance phase and reduced effort of the medial gastrocnemius muscle throughout the pre-swing phase were also observed in the RAG condition. In addition, walking with the assistance of GEMS resulted in a significant increase in foot pressure distribution, specifically in maximum force and peak pressure of the total foot, medial masks, anterior masks and posterior masks. The results of the present study reveal that GEMS may present an alternative way of restoring age-related changes in gait such as gait instability with muscle weakness, reduced step force and lower foot pressure in elderly adults. In addition, GEMS improved gait performance by improving push-off power and walking speed and reducing muscle activity in the lower

Invariant hip moment pattern while walking with a robotic hip exoskeleton.

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Lewis, Cara L; Ferris, Daniel P

2011-03-15

Robotic lower limb exoskeletons hold significant potential for gait assistance and rehabilitation; however, we have a limited understanding of how people adapt to walking with robotic devices. The purpose of this study was to test the hypothesis that people reduce net muscle moments about their joints when robotic assistance is provided. This reduction in muscle moment results in a total joint moment (muscle plus exoskeleton) that is the same as the moment without the robotic assistance despite potential differences in joint angles. To test this hypothesis, eight healthy subjects trained with the robotic hip exoskeleton while walking on a force-measuring treadmill. The exoskeleton provided hip flexion assistance from approximately 33% to 53% of the gait cycle. We calculated the root mean squared difference (RMSD) between the average of data from the last 15 min of the powered condition and the unpowered condition. After completing three 30-min training sessions, the hip exoskeleton provided 27% of the total peak hip flexion moment during gait. Despite this substantial contribution from the exoskeleton, subjects walked with a total hip moment pattern (muscle plus exoskeleton) that was almost identical and more similar to the unpowered condition than the hip angle pattern (hip moment RMSD 0.027, angle RMSD 0.134, p<0.001). The angle and moment RMSD were not different for the knee and ankle joints. These findings support the concept that people adopt walking patterns with similar joint moment patterns despite differences in hip joint angles for a given walking speed. Copyright © 2011 Elsevier Ltd. All rights reserved.

Artificial Walking Technologies to Improve Gait in Cerebral Palsy: Multichannel Neuromuscular Stimulation.

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Rose, Jessica; Cahill-Rowley, Katelyn; Butler, Erin E

2017-11-01

Cerebral palsy (CP) is the most common childhood motor disability and often results in debilitating walking abnormalities, such as flexed-knee and stiff-knee gait. Current medical and surgical treatments are only partially effective in improving gait abnormalities and may cause significant muscle weakness. However, emerging artificial walking technologies, such as step-initiated, multichannel neuromuscular electrical stimulation (NMES), can substantially improve gait patterns and promote muscle strength in children with spastic CP. NMES may also be applied to specific lumbar-sacral sensory roots to reduce spasticity. Development of tablet computer-based multichannel NMES can leverage lightweight, wearable wireless stimulators, advanced control design, and surface electrodes to activate lower-limb muscles. Musculoskeletal models have been used to characterize muscle contributions to unimpaired gait and identify high muscle demands, which can help guide multichannel NMES-assisted gait protocols. In addition, patient-specific NMES-assisted gait protocols based on 3D gait analysis can facilitate the appropriate activation of lower-limb muscles to achieve a more functional gait: stance-phase hip and knee extension and swing-phase sequence of hip and knee flexion followed by rapid knee extension. NMES-assisted gait treatment can be conducted as either clinic-based or home-based programs. Rigorous testing of multichannel NMES-assisted gait training protocols will determine optimal treatment dosage for future clinical trials. Evidence-based outcome evaluation using 3D kinematics or temporal-spatial gait parameters will help determine immediate neuroprosthetic effects and longer term neurotherapeutic effects of step-initiated, multichannel NMES-assisted gait in children with spastic CP. Multichannel NMES is a promising assistive technology to help children with spastic CP achieve a more upright, functional gait. © 2017 International Center for Artificial Organs and

Biofeedback for robotic gait rehabilitation

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Colombo Gery

2007-01-01

Full Text Available Abstract Background Development and increasing acceptance of rehabilitation robots as well as advances in technology allow new forms of therapy for patients with neurological disorders. Robot-assisted gait therapy can increase the training duration and the intensity for the patients while reducing the physical strain for the therapist. Optimal training effects during gait therapy generally depend on appropriate feedback about performance. Compared to manual treadmill therapy, there is a loss of physical interaction between therapist and patient with robotic gait retraining. Thus, it is difficult for the therapist to assess the necessary feedback and instructions. The aim of this study was to define a biofeedback system for a gait training robot and test its usability in subjects without neurological disorders. Methods To provide an overview of biofeedback and motivation methods applied in gait rehabilitation, previous publications and results from our own research are reviewed. A biofeedback method is presented showing how a rehabilitation robot can assess the patients' performance and deliver augmented feedback. For validation, three subjects without neurological disorders walked in a rehabilitation robot for treadmill training. Several training parameters, such as body weight support and treadmill speed, were varied to assess the robustness of the biofeedback calculation to confounding factors. Results The biofeedback values correlated well with the different activity levels of the subjects. Changes in body weight support and treadmill velocity had a minor effect on the biofeedback values. The synchronization of the robot and the treadmill affected the biofeedback values describing the stance phase. Conclusion Robot-aided assessment and feedback can extend and improve robot-aided training devices. The presented method estimates the patients' gait performance with the use of the robot's existing sensors, and displays the resulting biofeedback

Gait post-stroke: Pathophysiology and rehabilitation strategies.

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Beyaert, C; Vasa, R; Frykberg, G E

2015-11-01

We reviewed neural control and biomechanical description of gait in both non-disabled and post-stroke subjects. In addition, we reviewed most of the gait rehabilitation strategies currently in use or in development and observed their principles in relation to recent pathophysiology of post-stroke gait. In both non-disabled and post-stroke subjects, motor control is organized on a task-oriented basis using a common set of a few muscle modules to simultaneously achieve body support, balance control, and forward progression during gait. Hemiparesis following stroke is due to disruption of descending neural pathways, usually with no direct lesion of the brainstem and cerebellar structures involved in motor automatic processes. Post-stroke, improvements of motor activities including standing and locomotion are variable but are typically characterized by a common postural behaviour which involves the unaffected side more for body support and balance control, likely in response to initial muscle weakness of the affected side. Various rehabilitation strategies are regularly used or in development, targeting muscle activity, postural and gait tasks, using more or less high-technology equipment. Reduced walking speed often improves with time and with various rehabilitation strategies, but asymmetric postural behaviour during standing and walking is often reinforced, maintained, or only transitorily decreased. This asymmetric compensatory postural behaviour appears to be robust, driven by support and balance tasks maintaining the predominant use of the unaffected side over the initially impaired affected side. Based on these elements, stroke rehabilitation including affected muscle strengthening and often stretching would first need to correct the postural asymmetric pattern by exploiting postural automatic processes in various particular motor tasks secondarily beneficial to gait. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Multiple gait parameters derived from iPod accelerometry predict age-related gait changes

NARCIS (Netherlands)

Kosse, Nienke; Vuillerme, Nicolas; Hortobagyi, Tibor; Lamoth, Claude

Introduction Normative data of how natural aging affects gait can serve as a frame of reference for changes in gait dynamics due to pathologies. Therefore, the present study aims (1) to identify gait variables sensitive to age-related changes in gait over the adult life span using the iPod and (2)

Invariant ankle moment patterns when walking with and without a robotic ankle exoskeleton.

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Kao, Pei-Chun; Lewis, Cara L; Ferris, Daniel P

2010-01-19

To guide development of robotic lower limb exoskeletons, it is necessary to understand how humans adapt to powered assistance. The purposes of this study were to quantify joint moments while healthy subjects adapted to a robotic ankle exoskeleton and to determine if the period of motor adaptation is dependent on the magnitude of robotic assistance. The pneumatically powered ankle exoskeleton provided plantar flexor torque controlled by the wearer's soleus electromyography (EMG). Eleven naïve individuals completed two 30-min sessions walking on a split-belt instrumented treadmill at 1.25m/s while wearing the ankle exoskeleton. After two sessions of practice, subjects reduced their soleus EMG activation by approximately 36% and walked with total ankle moment patterns similar to their unassisted gait (r(2)=0.98+/-0.02, THSD, p>0.05). They had substantially different ankle kinematic patterns compared to their unassisted gait (r(2)=0.79+/-0.12, THSD, probotic ankle exoskeleton (Gordon and Ferris, 2007). Our results strongly suggest that humans aim for similar joint moment patterns when walking with robotic assistance rather than similar kinematic patterns. In addition, greater robotic assistance provided during initial use results in a longer adaptation process than lesser robotic assistance. Copyright 2009 Elsevier Ltd. All rights reserved.

Gait Analysis Using Computer Vision Based on Cloud Platform and Mobile Device

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Mario Nieto-Hidalgo

2018-01-01

Full Text Available Frailty and senility are syndromes that affect elderly people. The ageing process involves a decay of cognitive and motor functions which often produce an impact on the quality of life of elderly people. Some studies have linked this deterioration of cognitive and motor function to gait patterns. Thus, gait analysis can be a powerful tool to assess frailty and senility syndromes. In this paper, we propose a vision-based gait analysis approach performed on a smartphone with cloud computing assistance. Gait sequences recorded by a smartphone camera are processed by the smartphone itself to obtain spatiotemporal features. These features are uploaded onto the cloud in order to analyse and compare them to a stored database to render a diagnostic. The feature extraction method presented can work with both frontal and sagittal gait sequences although the sagittal view provides a better classification since an accuracy of 95% can be obtained.

Temporal self-similar synchronization patterns and scaling in ...

Indian Academy of Sciences (India)

Repulsively coupled oscillators; synchronization patterns; self-similar ... system, one expects multistable behavior in analogy to ..... More about the scaling relation between the long-period ... The third type of representation of phases is via.

Muscle Activation during Gait in Children with Duchenne Muscular Dystrophy.

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Juliette Ropars

Full Text Available The aim of this prospective study was to investigate changes in muscle activity during gait in children with Duchenne muscular Dystrophy (DMD. Dynamic surface electromyography recordings (EMGs of 16 children with DMD and pathological gait were compared with those of 15 control children. The activity of the rectus femoris (RF, vastus lateralis (VL, medial hamstrings (HS, tibialis anterior (TA and gastrocnemius soleus (GAS muscles was recorded and analysed quantitatively and qualitatively. The overall muscle activity in the children with DMD was significantly different from that of the control group. Percentage activation amplitudes of RF, HS and TA were greater throughout the gait cycle in the children with DMD and the timing of GAS activity differed from the control children. Significantly greater muscle coactivation was found in the children with DMD. There were no significant differences between sides. Since the motor command is normal in DMD, the hyper-activity and co-contractions likely compensate for gait instability and muscle weakness, however may have negative consequences on the muscles and may increase the energy cost of gait. Simple rehabilitative strategies such as targeted physical therapies may improve stability and thus the pattern of muscle activity.

Muscle Activation during Gait in Children with Duchenne Muscular Dystrophy.

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Ropars, Juliette; Lempereur, Mathieu; Vuillerot, Carole; Tiffreau, Vincent; Peudenier, Sylviane; Cuisset, Jean-Marie; Pereon, Yann; Leboeuf, Fabien; Delporte, Ludovic; Delpierre, Yannick; Gross, Raphaël; Brochard, Sylvain

2016-01-01

The aim of this prospective study was to investigate changes in muscle activity during gait in children with Duchenne muscular Dystrophy (DMD). Dynamic surface electromyography recordings (EMGs) of 16 children with DMD and pathological gait were compared with those of 15 control children. The activity of the rectus femoris (RF), vastus lateralis (VL), medial hamstrings (HS), tibialis anterior (TA) and gastrocnemius soleus (GAS) muscles was recorded and analysed quantitatively and qualitatively. The overall muscle activity in the children with DMD was significantly different from that of the control group. Percentage activation amplitudes of RF, HS and TA were greater throughout the gait cycle in the children with DMD and the timing of GAS activity differed from the control children. Significantly greater muscle coactivation was found in the children with DMD. There were no significant differences between sides. Since the motor command is normal in DMD, the hyper-activity and co-contractions likely compensate for gait instability and muscle weakness, however may have negative consequences on the muscles and may increase the energy cost of gait. Simple rehabilitative strategies such as targeted physical therapies may improve stability and thus the pattern of muscle activity.

FreeWalker: a smart insole for longitudinal gait analysis.

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Wang, Baitong; Rajput, Kuldeep Singh; Tam, Wing-Kin; Tung, Anthony K H; Yang, Zhi

2015-08-01

Gait analysis is an important diagnostic measure to investigate the pattern of walking. Traditional gait analysis is generally carried out in a gait lab, with equipped force and body tracking sensors, which needs a trained medical professional to interpret the results. This procedure is tedious, expensive, and unreliable and makes it difficult to track the progress across multiple visits. In this paper, we present a smart insole called FreeWalker, which provides quantitative gait analysis outside the confinement of traditional lab, at low- cost. The insole consists of eight pressure sensors and two motion tracking sensors, i.e. 3-axis accelerometer and 3-axis gyroscope. This enables measurement of under-foot pressure distribution and motion sequences in real-time. The insole is enabled with onboard SD card as well as wireless data transmission, which help in continuous gait-cycle analysis. The data is then sent to a gateway, for analysis and interpretation of data, using a user interface where gait features are graphically displayed. We also present validation result of a subject's left foot, who was asked to perform a specific task. Experiment results show that we could achieve a data-sampling rate of over 1 KHz, transmitting data up to a distance of 20 meter and maintain a battery life of around 24 hours. Taking advantage of these features, FreeWalker can be used in various applications, like medical diagnosis, rehabilitation, sports and entertainment.

Measuring Gait Quality in Parkinson’s Disease through Real-Time Gait Phase Recognition

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Ilaria Mileti

2018-03-01

Full Text Available Monitoring gait quality in daily activities through wearable sensors has the potential to improve medical assessment in Parkinson’s Disease (PD. In this study, four gait partitioning methods, two based on thresholds and two based on a machine learning approach, considering the four-phase model, were compared. The methods were tested on 26 PD patients, both in OFF and ON levodopa conditions, and 11 healthy subjects, during walking tasks. All subjects were equipped with inertial sensors placed on feet. Force resistive sensors were used to assess reference time sequence of gait phases. Goodness Index (G was evaluated to assess accuracy in gait phases estimation. A novel synthetic index called Gait Phase Quality Index (GPQI was proposed for gait quality assessment. Results revealed optimum performance (G < 0.25 for three tested methods and good performance (0.25 < G < 0.70 for one threshold method. The GPQI resulted significantly higher in PD patients than in healthy subjects, showing a moderate correlation with clinical scales score. Furthermore, in patients with severe gait impairment, GPQI was found higher in OFF than in ON state. Our results unveil the possibility of monitoring gait quality in PD through real-time gait partitioning based on wearable sensors.

Gait Analysis Using Wearable Sensors

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Hutian Feng

2012-02-01

Full Text Available Gait analysis using wearable sensors is an inexpensive, convenient, and efficient manner of providing useful information for multiple health-related applications. As a clinical tool applied in the rehabilitation and diagnosis of medical conditions and sport activities, gait analysis using wearable sensors shows great prospects. The current paper reviews available wearable sensors and ambulatory gait analysis methods based on the various wearable sensors. After an introduction of the gait phases, the principles and features of wearable sensors used in gait analysis are provided. The gait analysis methods based on wearable sensors is divided into gait kinematics, gait kinetics, and electromyography. Studies on the current methods are reviewed, and applications in sports, rehabilitation, and clinical diagnosis are summarized separately. With the development of sensor technology and the analysis method, gait analysis using wearable sensors is expected to play an increasingly important role in clinical applications.

Gait Analysis Using Wearable Sensors

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Tao, Weijun; Liu, Tao; Zheng, Rencheng; Feng, Hutian

2012-01-01

Gait analysis using wearable sensors is an inexpensive, convenient, and efficient manner of providing useful information for multiple health-related applications. As a clinical tool applied in the rehabilitation and diagnosis of medical conditions and sport activities, gait analysis using wearable sensors shows great prospects. The current paper reviews available wearable sensors and ambulatory gait analysis methods based on the various wearable sensors. After an introduction of the gait phases, the principles and features of wearable sensors used in gait analysis are provided. The gait analysis methods based on wearable sensors is divided into gait kinematics, gait kinetics, and electromyography. Studies on the current methods are reviewed, and applications in sports, rehabilitation, and clinical diagnosis are summarized separately. With the development of sensor technology and the analysis method, gait analysis using wearable sensors is expected to play an increasingly important role in clinical applications. PMID:22438763

Gait Implications of Visual Field Damage from Glaucoma.

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Mihailovic, Aleksandra; Swenor, Bonnielin K; Friedman, David S; West, Sheila K; Gitlin, Laura N; Ramulu, Pradeep Y

2017-06-01

To evaluate fall-relevant gait features in older glaucoma patients. The GAITRite Electronic Walkway was used to define fall-related gait parameters in 239 patients with suspected or manifest glaucoma under normal usual-pace walking conditions and while carrying a cup or tray. Multiple linear regression models assessed the association between gait parameters and integrated visual field (IVF) sensitivity after controlling for age, race, sex, medications, and comorbid illness. Under normal walking conditions, worse IVF sensitivity was associated with a wider base of support (β = 0.60 cm/5 dB IVF sensitivity decrement, 95% confidence interval [CI] = 0.12-1.09, P = 0.016). Worse IVF sensitivity was not associated with slower gait speed, shorter step or stride length, or greater left-right drift under normal walking conditions ( P > 0.05 for all), but was during cup and/or tray carrying conditions ( P < 0.05 for all). Worse IVF sensitivity was positively associated with greater stride-to-stride variability in step length, stride length, and stride velocity ( P < 0.005 for all). Inferior and superior IVF sensitivity demonstrated associations with each of the above gait parameters as well, though these associations were consistently similar to, or weaker than, the associations noted for overall IVF sensitivity. Glaucoma severity was associated with several gait parameters predictive of higher fall risk in prior studies, particularly measures of stride-to-stride variability. Gait may be useful in identifying glaucoma patients at higher risk of falls, and in designing and testing interventions to prevent falls in this high-risk group. These findings could serve to inform the development of the interventions for falls prevention in glaucoma patients.

Control entropy identifies differential changes in complexity of walking and running gait patterns with increasing speed in highly trained runners.

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McGregor, Stephen J; Busa, Michael A; Skufca, Joseph; Yaggie, James A; Bollt, Erik M

2009-06-01

Regularity statistics have been previously applied to walking gait measures in the hope of gaining insight into the complexity of gait under different conditions and in different populations. Traditional regularity statistics are subject to the requirement of stationarity, a limitation for examining changes in complexity under dynamic conditions such as exhaustive exercise. Using a novel measure, control entropy (CE), applied to triaxial continuous accelerometry, we report changes in complexity of walking and running during increasing speeds up to exhaustion in highly trained runners. We further apply Karhunen-Loeve analysis in a new and novel way to the patterns of CE responses in each of the three axes to identify dominant modes of CE responses in the vertical, mediolateral, and anterior/posterior planes. The differential CE responses observed between the different axes in this select population provide insight into the constraints of walking and running in those who may have optimized locomotion. Future comparisons between athletes, healthy untrained, and clinical populations using this approach may help elucidate differences between optimized and diseased locomotor control.

Gait outcome following outpatient physiotherapy based on the Bobath concept in people post stroke.

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Lennon, Sheila; Ashburn, Ann; Baxter, David

The purpose of this study was to characterize the gait cycle of patients with hemiplegia before and after a period of outpatient physiotherapy based on the Bobath concept. Nine patients, at least 6 weeks post stroke and recently discharged from a stroke unit, were measured before and after a period of outpatient physiotherapy (mean duration = 17.4 weeks). Therapy was documented using a treatment checklist for each patient. The primary outcome measures were a number of gait variables related to the therapists' treatment hypothesis, recorded during the gait cycle using the CODA motion analysis system. Other secondary outcome measures were the Motor Assessment Scale, Modified Ashworth Scale, subtests of the Sodring Motor Evaluation Scale, the Step test, a 10-m walk test, the Barthel Index and the London Handicap Score. Recovery of more normal gait patterns in the gait cycle (using motion analysis) did not occur. Significant changes in temporal parameters (loading response, single support time) for both legs, in one kinematic (dorsiflexion during stance) and one kinetic variable on the unaffected side (hip flexor moment), and most of the clinical measures of impairment, activity and participation (with the exception of the Modified Ashworth Scale and the 10-m walk) were noted. Study findings did not support the hypothesis that the Bobath approach restored more normal movement patterns to the gait cycle. Further research is required to investigate the treatment techniques that are effective at improving walking ability in people after stroke.

DeepGait: A Learning Deep Convolutional Representation for View-Invariant Gait Recognition Using Joint Bayesian

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Chao Li

2017-02-01

Full Text Available Human gait, as a soft biometric, helps to recognize people through their walking. To further improve the recognition performance, we propose a novel video sensor-based gait representation, DeepGait, using deep convolutional features and introduce Joint Bayesian to model view variance. DeepGait is generated by using a pre-trained “very deep” network “D-Net” (VGG-D without any fine-tuning. For non-view setting, DeepGait outperforms hand-crafted representations (e.g., Gait Energy Image, Frequency-Domain Feature and Gait Flow Image, etc.. Furthermore, for cross-view setting, 256-dimensional DeepGait after PCA significantly outperforms the state-of-the-art methods on the OU-ISR large population (OULP dataset. The OULP dataset, which includes 4007 subjects, makes our result reliable in a statistically reliable way.

Comparison of Electromyographic Activity Pattern of Knee Two-Joint Muscles between Youngs and Olders in Gait Different Speeds

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Hamideh Khodaveisi

2016-01-01

Full Text Available Objective: In recent years, it has been focused much attention on gait analysis. Factors such as speed, age and gender affect gait parameters. The purpose of the present study was to compare the electromyographic activity pattern of knee two-joint muscles between younger and older subjects in different gait speeds. Matterials & Methods: The method of current study was analytical cross-sectional method in which 15 healthy young men and 15 old men, were selected conveniently. Electromyographic activity of rectus femoris, biceps femoris, semitendinus and gastrocenemius were recorded during walking with preferred (100%, slow (80% and fast (120% speeds in a 10 meter walkway. Normalized RMSs of muscles were compared using RM-ANOVA and Tokey’s tests by SPSS 18 software. Results: According to results, RMSs of rectus femoris in midstance (P<0.01 and gastrocenemius in loading response (P=0.02 phases in all walking speeds were higher in older subjects than in younger ones, and it increased with speed in both age groups (P<0.01. Biceps femoris RMS in terminal stance at 80% speed, was lower in older subjects than in younger ones (P=0.01 and it increased with walking speed (P=0.01. Semitendinus activity in loading and midstance phases at 120% speed was higher in older subjects than in younger ones (P<0.01, and it increased with speed in both age groups in swing phase (P<0.05. Conclusion: According to the results, older subjects have more muscle co-contraction around knee at high speed in midstance phase than younger subjects. These age-related changes in muscle activity, leads to increase in joint stiffness and stability during single support, and probably play a role in reducing push off power at faster speeds.

Body mass index affects knee joint mechanics during gait differently with and without moderate knee osteoarthritis.

Science.gov (United States)

Harding, Graeme T; Hubley-Kozey, Cheryl L; Dunbar, Michael J; Stanish, William D; Astephen Wilson, Janie L

2012-11-01

Obesity is a highly cited risk factor for knee osteoarthritis (OA), but its role in knee OA pathogenesis and progression is not as clear. Excess weight may contribute to an increased mechanical burden and altered dynamic movement and loading patterns at the knee. The objective of this study was to examine the interacting role of moderate knee OA disease presence and obesity on knee joint mechanics during gait. Gait analysis was performed on 104 asymptomatic and 140 individuals with moderate knee OA. Each subject group was divided into three body mass categories based on body mass index (BMI): healthy weight (BMI30). Three-dimensional knee joint angles and net external knee joint moments were calculated and waveform principal component analysis (PCA) was applied to extract major patterns of variability from each. PC scores for major patterns were compared between groups using a two-factor ANOVA. Significant BMI main effects were found in the pattern of the knee adduction moment, the knee flexion moment, and the knee rotation moment during gait. Two interaction effects between moderate OA disease presence and BMI were also found that described different changes in the knee flexion moment and the knee flexion angle with increased BMI with and without knee OA. Our results suggest that increased BMI is associated with different changes in biomechanical patterns of the knee joint during gait depending on the presence of moderate knee OA. Copyright © 2012 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Gait variability and motor control in people with knee osteoarthritis.

Science.gov (United States)

Alkjaer, Tine; Raffalt, Peter C; Dalsgaard, Helle; Simonsen, Erik B; Petersen, Nicolas C; Bliddal, Henning; Henriksen, Marius

2015-10-01

Knee osteoarthritis (OA) is a common disease that impairs walking ability and function. We compared the temporal gait variability and motor control in people with knee OA with healthy controls. The purpose was to test the hypothesis that the temporal gait variability would reflect a more stereotypic pattern in people with knee OA compared with healthy age-matched subjects. To assess the gait variability the temporal structure of the ankle and knee joint kinematics was quantified by the largest Lyapunov exponent and the stride time fluctuations were quantified by sample entropy and detrended fluctuation analysis. The motor control was assessed by the soleus (SO) Hoffmann (H)-reflex modulation and muscle co-activation during walking. The results showed no statistically significant mean group differences in any of the gait variability measures or muscle co-activation levels. The SO H-reflex amplitude was significantly higher in the knee OA group around heel strike when compared with the controls. The mean group difference in the H-reflex in the initial part of the stance phase (control-knee OA) was -6.6% Mmax (95% CI: -10.4 to -2.7, p=0.041). The present OA group reported relatively small impact of their disease. These results suggest that the OA group in general sustained a normal gait pattern with natural variability but with suggestions of facilitated SO H-reflex in the swing to stance phase transition. We speculate that the difference in SO H-reflex modulation reflects that the OA group increased the excitability of the soleus stretch reflex as a preparatory mechanism to avoid sudden collapse of the knee joint which is not uncommon in knee OA. Copyright © 2015 Elsevier B.V. All rights reserved.

A Validated Smartphone-Based Assessment of Gait and Gait Variability in Parkinson's Disease.

Directory of Open Access Journals (Sweden)

Robert J Ellis

Full Text Available A well-established connection exists between increased gait variability and greater fall likelihood in Parkinson's disease (PD; however, a portable, validated means of quantifying gait variability (and testing the efficacy of any intervention remains lacking. Furthermore, although rhythmic auditory cueing continues to receive attention as a promising gait therapy for PD, its widespread delivery remains bottlenecked. The present paper describes a smartphone-based mobile application ("SmartMOVE" to address both needs.The accuracy of smartphone-based gait analysis (utilizing the smartphone's built-in tri-axial accelerometer and gyroscope to calculate successive step times and step lengths was validated against two heel contact-based measurement devices: heel-mounted footswitch sensors (to capture step times and an instrumented pressure sensor mat (to capture step lengths. 12 PD patients and 12 age-matched healthy controls walked along a 26-m path during self-paced and metronome-cued conditions, with all three devices recording simultaneously.Four outcome measures of gait and gait variability were calculated. Mixed-factorial analysis of variance revealed several instances in which between-group differences (e.g., increased gait variability in PD patients relative to healthy controls yielded medium-to-large effect sizes (eta-squared values, and cueing-mediated changes (e.g., decreased gait variability when PD patients walked with auditory cues yielded small-to-medium effect sizes-while at the same time, device-related measurement error yielded small-to-negligible effect sizes.These findings highlight specific opportunities for smartphone-based gait analysis to serve as an alternative to conventional gait analysis methods (e.g., footswitch systems or sensor-embedded walkways, particularly when those methods are cost-prohibitive, cumbersome, or inconvenient.

Evidence of end-effector based gait machines in gait rehabilitation after CNS lesion.

Science.gov (United States)

Hesse, S; Schattat, N; Mehrholz, J; Werner, C

2013-01-01

A task-specific repetitive approach in gait rehabilitation after CNS lesion is well accepted nowadays. To ease the therapists' and patients' physical effort, the past two decades have seen the introduction of gait machines to intensify the amount of gait practice. Two principles have emerged, an exoskeleton- and an endeffector-based approach. Both systems share the harness and the body weight support. With the end-effector-based devices, the patients' feet are positioned on two foot plates, whose movements simulate stance and swing phase. This article provides an overview on the end-effector based machine's effectiveness regarding the restoration of gait. For the electromechanical gait trainer GT I, a meta analysis identified nine controlled trials (RCT) in stroke subjects (n = 568) and were analyzed to detect differences between end-effector-based locomotion + physiotherapy and physiotherapy alone. Patients practising with the machine effected in a superior gait ability (210 out of 319 patients, 65.8% vs. 96 out of 249 patients, 38.6%, respectively, Z = 2.29, p = 0.020), due to a larger training intensity. Only single RCTs have been reported for other devices and etiologies. The introduction of end-effector based gait machines has opened a new succesful chapter in gait rehabilitation after CNS lesion.

Gait and its assessment in psychiatry

OpenAIRE

Sanders, Richard D.; Gillig, Paulette Marie

2010-01-01

Gait reflects all levels of nervous system function. In psychiatry, gait disturbances reflecting cortical and subcortical dysfunction are often seen. Observing spontaneous gait, sometimes augmented by a few brief tests, can be highly informative. The authors briefly review the neuroanatomy of gait, review gait abnormalities seen in psychiatric and neurologic disorders, and describe the assessment of gait.

Toward Multimodal Human-Robot Interaction to Enhance Active Participation of Users in Gait Rehabilitation.

Science.gov (United States)

Gui, Kai; Liu, Honghai; Zhang, Dingguo

2017-11-01

Robotic exoskeletons for physical rehabilitation have been utilized for retraining patients suffering from paraplegia and enhancing motor recovery in recent years. However, users are not voluntarily involved in most systems. This paper aims to develop a locomotion trainer with multiple gait patterns, which can be controlled by the active motion intention of users. A multimodal human-robot interaction (HRI) system is established to enhance subject's active participation during gait rehabilitation, which includes cognitive HRI (cHRI) and physical HRI (pHRI). The cHRI adopts brain-computer interface based on steady-state visual evoked potential. The pHRI is realized via admittance control based on electromyography. A central pattern generator is utilized to produce rhythmic and continuous lower joint trajectories, and its state variables are regulated by cHRI and pHRI. A custom-made leg exoskeleton prototype with the proposed multimodal HRI is tested on healthy subjects and stroke patients. The results show that voluntary and active participation can be effectively involved to achieve various assistive gait patterns.

Variability and repeatability analysis of plantar pressure during gait in older people.

Science.gov (United States)

Franco, Pedro S; Silva, Caio Borella P da; Rocha, Emmanuel S da; Carpes, Felipe P

2015-01-01

Repeatability and variability of the plantar pressure during walking are important components in the clinical assessment of the elderly. However, there is a lack of information on the uniformity of plantar pressure patterns in the elderly. To analyze the repeatability and variability in plantar pressure considering mean, peak and asymmetries during aged gait. Plantar pressure was monitored in four different days for ten elderly subjects (5 female), with mean±standard-deviation age of 73±6 years, walking barefoot at preferred speed. Data were compared between steps for each day and between different days. Mean and peak plantar pressure values were similar between the different days of evaluation. Asymmetry indexes were similar between the different days evaluated. Plantar pressure presented a consistent pattern in the elderly. However, the asymmetry indexes observed suggest that the elderly are exposed to repetitive asymmetric loading during locomotion. Such result requires further investigation, especially concerning the role of these asymmetries for development of articular injuries. Copyright © 2015 Elsevier Editora Ltda. All rights reserved.

Gait Deviation Index, Gait Profile Score and Gait Variable Score in children with spastic cerebral palsy

DEFF Research Database (Denmark)

Rasmussen, Helle Mätzke; Nielsen, Dennis Brandborg; Pedersen, Niels Wisbech

2015-01-01

Abstract The Gait Deviation Index (GDI) and Gait Profile Score (GPS) are the most used summary measures of gait in children with cerebral palsy (CP). However, the reliability and agreement of these indices have not been investigated, limiting their clinimetric quality for research and clinical...... to good reliability with ICCs of 0.4–0.7. The agreement for the GDI and the logarithmically transformed GPS, in terms of the standard error of measurement as a percentage of the grand mean (SEM%) varied from 4.1 to 6.7%, whilst the smallest detectable change in percent (SDC%) ranged from 11.3 to 18...

Evaluating the Applicability of Data-Driven Dietary Patterns to Independent Samples with a Focus on Measurement Tools for Pattern Similarity.

Science.gov (United States)

Castelló, Adela; Buijsse, Brian; Martín, Miguel; Ruiz, Amparo; Casas, Ana M; Baena-Cañada, Jose M; Pastor-Barriuso, Roberto; Antolín, Silvia; Ramos, Manuel; Muñoz, Monserrat; Lluch, Ana; de Juan-Ferré, Ana; Jara, Carlos; Lope, Virginia; Jimeno, María A; Arriola-Arellano, Esperanza; Díaz, Elena; Guillem, Vicente; Carrasco, Eva; Pérez-Gómez, Beatriz; Vioque, Jesús; Pollán, Marina

2016-12-01

Diet is a key modifiable risk for many chronic diseases, but it remains unclear whether dietary patterns from one study sample are generalizable to other independent populations. The primary objective of this study was to assess whether data-driven dietary patterns from one study sample are applicable to other populations. The secondary objective was to assess the validity of two criteria of pattern similarity. Six dietary patterns-Western (n=3), Mediterranean, Prudent, and Healthy- from three published studies on breast cancer were reconstructed in a case-control study of 973 breast cancer patients and 973 controls. Three more internal patterns (Western, Prudent, and Mediterranean) were derived from this case-control study's own data. Applicability was assessed by comparing the six reconstructed patterns with the three internal dietary patterns, using the congruence coefficient (CC) between pattern loadings. In cases where any pair met either of two commonly used criteria for declaring patterns similar (CC ≥0.85 or a statistically significant [Pdietary patterns was double-checked by comparing their associations to risk for breast cancer, to assess whether those two criteria of similarity are actually reliable. Five of the six reconstructed dietary patterns showed high congruence (CC >0.9) to their corresponding dietary pattern derived from the case-control study's data. Similar associations with risk for breast cancer were found in all pairs of dietary patterns that had high CC but not in all pairs of dietary patterns with statistically significant correlations. Similar dietary patterns can be found in independent samples. The P value of a correlation coefficient is less reliable than the CC as a criterion for declaring two dietary patterns similar. This study shows that diet scores based on a particular study are generalizable to other populations. Copyright © 2016 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Gait analysis of young male patients diagnosed with primary bladder neck obstruction.

Science.gov (United States)

Zago, Matteo; Camerota, Tommaso Ciro; Pisu, Stefano; Ciprandi, Daniela; Sforza, Chiarella

2017-08-01

Primary bladder neck obstruction (PBNO) represents an inappropriate or inadequate relaxation of the bladder neck during micturition. Based on the observation of an increased rate of postural imbalances in male patients with PBNO, we hypothesized a possible role of an unbalanced biomechanics of the pelvis on urethral sphincters activity. Our aim was to identify kinematic imbalances, usually disregarded in PBNO patients, and which could eventually be involved in the etiopathogenesis of the disease. Seven male adult patients (39.6±7.1years) were recruited; in all patients, PBNO was suspected at bladder diary and uroflowmetry, and was endoscopically confirmed with urethroscopy. Participants gait was recorded with a motion capture system (BTS Spa, Italy) to obtain three-dimensional joint angles and gait parameters. Multivariate statistics based on a Principal Component model allowed to assess the similarity of patients' gait patterns with respect to control subjects. The main finding is that patients with PBNO showed significant discordance in the observations at the ankle and pelvis level. Additionally, 6/7 patients demonstrated altered trunk positions compared to normal curves. We suggest that the identified postural imbalances could represent the cause for an anomalous activation of pelvic floor muscles (hypertonia). The consequent urinary sphincters hypercontraction may be responsible for the development of voiding dysfunction in male patients with no significant morphological alterations. Results reinforced the hypothesis of an etiopathogenetic role of postural imbalances on primary bladder neck obstruction in male patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

A walker with a device of partial suspension for patients with gait disturbance: body weight supported walker.

Science.gov (United States)

Ochi, Mitsuhiro; Makino, Kenichiro; Wada, Futoshi; Saeki, Satoru; Hachisuka, Kenji

2009-09-01

We developed a walker, the Body Weight Supported (BWS) Walker, with a device of partial suspension for patients with gait disturbance. It consists of a light frame with casters, a harness, and a winch system. One therapist alone can perform gait training safely with the BWS Walker without any additional physical load, even if a patient has severe gait disturbance, and the therapist can concentrate on evaluating and improving the patient' s standing balance and gait pattern. Because the BWS Walker is less expensive, simpler, and easier to operate than other BWS systems, we believe the BWS Walker can be widely applicable in training for patients with severe and moderate gait disturbance.

Gait recognition using kinect and locally linear embedding ...

African Journals Online (AJOL)

This paper presents the use of locally linear embedding (LLE) as feature extraction technique for classifying a person's identity based on their walking gait patterns. Skeleton data acquired from Microsoft Kinect camera were used as an input for (1). Multilayer Perceptron (MLP) and (2). LLE with MLP. The MLP classification ...

Gait-related cerebral alterations in patients with Parkinson's disease with freezing of gait

NARCIS (Netherlands)

Snijders, A.H.; Leunissen, H.P.; Bakker, M.; Overeem, S.; Helmich, R.C.G.; Bloem, B.R.; Toni, I.

2011-01-01

Freezing of gait is a common, debilitating feature of Parkinson’s disease. We have studied gait planning in patients with freezing of gait, using motor imagery of walking in combination with functional magnetic resonance imaging. This approach exploits the large neural overlap that exists between

Gait-related cerebral alterations in patients with Parkinson's disease with freezing of gait

NARCIS (Netherlands)

Snijders, A.H.; Leunissen, I.; Bakker, M.; Overeem, S.; Helmich, R.C.G.; Bloem, B.R.; Toni, I.

2011-01-01

Freezing of gait is a common, debilitating feature of Parkinson's disease. We have studied gait planning in patients with freezing of gait, using motor imagery of walking in combination with functional magnetic resonance imaging. This approach exploits the large neural overlap that exists between

A mechanized gait trainer for restoring gait in nonambulatory subjects.

Science.gov (United States)

Hesse, S; Uhlenbrock, D; Werner, C; Bardeleben, A

2000-09-01

To construct an advanced mechanized gait trainer to enable patients the repetitive practice of a gaitlike movement without overstraining therapists. DEVICE: Prototype gait trainer that simulates the phases of gait (by generating a ratio of 40% to 60% between swing and stance phases), supports the subjects according to their ability (lifts the foot during swing phase), and controls the center of mass in the vertical and horizontal directions. Two nonambulatory, hemiparetic patients who regained their walking ability after 4 weeks of daily training on the gait trainer, a 55-year-old woman and a 62-year-old man, both of whom had a first-time ischemic stroke. Four weeks of training, five times a week, each session 20 minutes long. Functional ambulation category (FAC, levels 0-5) to assess gait ability and ground level walking velocity. Rivermead motor assessment score (RMAS, 0-13) to assess gross motor function. Patient 1: At the end of treatment, she was able to walk independently on level ground with use of a walking stick. Her walking velocity had improved from .29m/sec to .59m/sec. Her RMAS score increased from 4 to 10, meaning she could walk at least 40 meters outside, pick up objects from floor, and climb stairs independently. Patient 2: At end of 4-week training, he could walk independently on even surfaces (FAC level 4), using an ankle-foot orthosis and a walking stick. His walking velocity improved from .14m/sec to .63m/sec. His RMAS increased from 3 to 10. The gait trainer enabled severely affected patients the repetitive practice of a gaitlike movement. Future studies may elucidate its value in gait rehabilitation of nonambulatory subjects.

Knee Trembling During Freezing of Gait Represents Multiple Anticipatory Postural Adjustments

Science.gov (United States)

Jacobs, Jesse V.; Nutt, John G.; Carlson-Kuhta, Patricia; Stephens, Marilee; Horak, Fay B.

2011-01-01

Freezing of gait (FoG) is an episodic, brief inability to step that delays gait initiation or interrupts ongoing gait. FoG is often associated with an alternating shaking of the knees, clinically referred to as knee trembling or trembling in place. The pathophysiology of FoG and of the concomitant trembling knees is unknown; impaired postural adjustment in preparation for stepping is one hypothesis. We examined anticipatory postural adjustments (APAs) prior to protective steps induced by a forward loss of balance in 10 Parkinson’s disease (PD) subjects with marked FoG and in 10 control subjects. The amplitude and timing of the APAs were determined from changes in the vertical ground-reaction forces recorded by a force plate under each foot and were confirmed by electromyographic recordings of bilateral medial gastrocnemius, tibialis anterior and tensor fascia latae muscles. Protective steps were accomplished with a single APA followed by a step for control subjects, whereas PD subjects frequently exhibited multiple, alternating APAs coexistent with the knee trembling commonly observed during FoG as well as delayed, inadequate or no stepping. These multiple APAs were not delayed in onset and were of similar or larger amplitude than the single APAs exhibited by the control subjects. These observations suggest that multiple APAs produce the knee trembling commonly associated with FoG and that FoG associated with a forward loss of balance is caused by an inability to couple a normal APA to the stepping motor pattern. PMID:19061889

Overload From Anxiety: A Non-Motor Cause for Gait Impairments in Parkinson's Disease.

Science.gov (United States)

Ehgoetz Martens, Kaylena A; Silveira, Carolina R A; Intzandt, Brittany N; Almeida, Quincy J

2018-01-01

Threatening situations lead to observable gait deficits in individuals with Parkinson's disease (PD) who suffer from high trait anxiety levels. The specific characteristics of gait that are affected appear to be similar to behaviors observed while walking during a dual-task (DT) condition. Yet, it remains unclear whether anxiety is similar to a cognitive load. If it were, then those with PD who have high trait anxiety might be expected to be more susceptible to DT interference during walking. Thus, the overall aim of this study was to evaluate whether trait anxiety influences gait during single-task (ST) and DT walking. Seventy participants (high-anxiety PD [HA-PD], N=26; low-anxiety PD [LA-PD], N=26; healthy control [HC], N=18) completed three ST and three DT walking trials on a data-collecting carpet. The secondary task consisted of digit monitoring while walking. Results showed that during both ST and DT gait, the HA-PD group demonstrated significant reductions in walking speed and step length, as well as increased step length variability and step time variability compared with healthy controls and the LA-PD group. Notably, ST walking in the HA-PD group resembled (i.e., it was not significantly different from) the gait behaviors seen during a DT in the LA-PD and HC groups. These results suggest that trait anxiety may consume processing resources and limit the ability to compensate for gait impairments in PD.

Automatic Setting Procedure for Exoskeleton-Assisted Overground Gait: Proof of Concept on Stroke Population

Directory of Open Access Journals (Sweden)

Marta Gandolla

2018-03-01

Full Text Available Stroke-related locomotor impairments are often associated with abnormal timing and intensity of recruitment of the affected and non-affected lower limb muscles. Restoring the proper lower limbs muscles activation is a key factor to facilitate recovery of gait capacity and performance, and to reduce maladaptive plasticity. Ekso is a wearable powered exoskeleton robot able to support over-ground gait training. The user controls the exoskeleton by triggering each single step during the gait cycle. The fine-tuning of the exoskeleton control system is crucial—it is set according to the residual functional abilities of the patient, and it needs to ensure lower limbs powered gait to be the most physiological as possible. This work focuses on the definition of an automatic calibration procedure able to detect the best Ekso setting for each patient. EMG activity has been recorded from Tibialis Anterior, Soleus, Rectus Femoris, and Semitendinosus muscles in a group of 7 healthy controls and 13 neurological patients. EMG signals have been processed so to obtain muscles activation patterns. The mean muscular activation pattern derived from the controls cohort has been set as reference. The developed automatic calibration procedure requires the patient to perform overground walking trials supported by the exoskeleton while changing parameters setting. The Gait Metric index is calculated for each trial, where the closer the performance is to the normative muscular activation pattern, in terms of both relative amplitude and timing, the higher the Gait Metric index is. The trial with the best Gait Metric index corresponds to the best parameters set. It has to be noted that the automatic computational calibration procedure is based on the same number of overground walking trials, and the same experimental set-up as in the current manual calibration procedure. The proposed approach allows supporting the rehabilitation team in the setting procedure. It has been

Automatic Setting Procedure for Exoskeleton-Assisted Overground Gait: Proof of Concept on Stroke Population.

Science.gov (United States)

Gandolla, Marta; Guanziroli, Eleonora; D'Angelo, Andrea; Cannaviello, Giovanni; Molteni, Franco; Pedrocchi, Alessandra

2018-01-01

Stroke-related locomotor impairments are often associated with abnormal timing and intensity of recruitment of the affected and non-affected lower limb muscles. Restoring the proper lower limbs muscles activation is a key factor to facilitate recovery of gait capacity and performance, and to reduce maladaptive plasticity. Ekso is a wearable powered exoskeleton robot able to support over-ground gait training. The user controls the exoskeleton by triggering each single step during the gait cycle. The fine-tuning of the exoskeleton control system is crucial-it is set according to the residual functional abilities of the patient, and it needs to ensure lower limbs powered gait to be the most physiological as possible. This work focuses on the definition of an automatic calibration procedure able to detect the best Ekso setting for each patient. EMG activity has been recorded from Tibialis Anterior, Soleus, Rectus Femoris, and Semitendinosus muscles in a group of 7 healthy controls and 13 neurological patients. EMG signals have been processed so to obtain muscles activation patterns. The mean muscular activation pattern derived from the controls cohort has been set as reference. The developed automatic calibration procedure requires the patient to perform overground walking trials supported by the exoskeleton while changing parameters setting. The Gait Metric index is calculated for each trial, where the closer the performance is to the normative muscular activation pattern, in terms of both relative amplitude and timing, the higher the Gait Metric index is. The trial with the best Gait Metric index corresponds to the best parameters set. It has to be noted that the automatic computational calibration procedure is based on the same number of overground walking trials, and the same experimental set-up as in the current manual calibration procedure. The proposed approach allows supporting the rehabilitation team in the setting procedure. It has been demonstrated to be

Automatic Setting Procedure for Exoskeleton-Assisted Overground Gait: Proof of Concept on Stroke Population

Science.gov (United States)

Gandolla, Marta; Guanziroli, Eleonora; D'Angelo, Andrea; Cannaviello, Giovanni; Molteni, Franco; Pedrocchi, Alessandra

2018-01-01

Stroke-related locomotor impairments are often associated with abnormal timing and intensity of recruitment of the affected and non-affected lower limb muscles. Restoring the proper lower limbs muscles activation is a key factor to facilitate recovery of gait capacity and performance, and to reduce maladaptive plasticity. Ekso is a wearable powered exoskeleton robot able to support over-ground gait training. The user controls the exoskeleton by triggering each single step during the gait cycle. The fine-tuning of the exoskeleton control system is crucial—it is set according to the residual functional abilities of the patient, and it needs to ensure lower limbs powered gait to be the most physiological as possible. This work focuses on the definition of an automatic calibration procedure able to detect the best Ekso setting for each patient. EMG activity has been recorded from Tibialis Anterior, Soleus, Rectus Femoris, and Semitendinosus muscles in a group of 7 healthy controls and 13 neurological patients. EMG signals have been processed so to obtain muscles activation patterns. The mean muscular activation pattern derived from the controls cohort has been set as reference. The developed automatic calibration procedure requires the patient to perform overground walking trials supported by the exoskeleton while changing parameters setting. The Gait Metric index is calculated for each trial, where the closer the performance is to the normative muscular activation pattern, in terms of both relative amplitude and timing, the higher the Gait Metric index is. The trial with the best Gait Metric index corresponds to the best parameters set. It has to be noted that the automatic computational calibration procedure is based on the same number of overground walking trials, and the same experimental set-up as in the current manual calibration procedure. The proposed approach allows supporting the rehabilitation team in the setting procedure. It has been demonstrated to be

Differences in center of pressure trajectory between normal and steppage gait

Science.gov (United States)

Jamshidi, Nima; Rostami, Mostafa; Najarian, Siamak; Menhaj, Mohammad Bagher; Saadatnia, Mohammad; Salami, Firooz

2010-01-01

BACKGROUND: This pilot study aimed to assess the differences in center of pressure trajectory in neuropathic patients with steppage gait. Steppage gait has previously been evaluated by several biomechanical methods, but plantar pressure distribution has been much less studied. The purpose of this study was to analyze the changes in center of pressure trajectory using a force plate. METHODS: The steppage gait group was selected from the patients using drop foot brace (25 male) and the control group was selected from Isfahan university students (20 male). They walked at self- selected speed at a mean of ten trials (+2) to collect the center of pressure using a force plate. Center of pressure patterns were categorized into four patterns based on the center of pressure displacement magnitude (spatial features) through time (temporal features) when the longitudinal axis of the insole was plotted as the Y- axis and the transverse axis of the insole as X- axis during stance phase. RESULTS: The horizontal angle measured from center of pressure linear regression was positive in the control group (4.6 ± 2.4) (p < 0.005), but negative in the patient group (- 2.3 ± 1.6) (p < 0.005). CONCLUSIONS: The finding of this research measured center of pressure trajectory in steppage gait over time, which is useful for designing better shoe sole and also orthopaedic device and better understanding of stability in patients with drop foot. PMID:21526056

Differences in center of pressure trajectory between normal and steppage gait

Directory of Open Access Journals (Sweden)

Nima Jamshidi

2010-01-01

Full Text Available Background: This pilot study aimed to assess the differences in center of pressure trajectory in neuropathic patients with steppage gait. Steppage gait has previously been evaluated by several biomechanical methods, but plantar pressure distribution has been much less studied. The purpose of this study was to analyze the changes in center of pressure tra-jectory using a force plate. Methods: The steppage gait group was selected from the patients using drop foot brace (25 male and the control group was selected from Isfahan university students (20 male. They walked at self- selected speed at a mean of ten tri-als (+2 to collect the center of pressure using a force plate. Center of pressure patterns were categorized into four pat-terns based on the center of pressure displacement magnitude (spatial features through time (temporal features when the longitudinal axis of the insole was plotted as the Y- axis and the transverse axis of the insole as X- axis during stance phase. Results: The horizontal angle measured from center of pressure linear regression was positive in the control group (4.6 ± 2.4 (p < 0.005, but negative in the patient group (- 2.3 ± 1.6 (p < 0.005. Conclusions: The finding of this research measured center of pressure trajectory in steppage gait over time, which is useful for designing better shoe sole and also orthopaedic device and better understanding of stability in patients with drop foot.

Gait variability measurements in lumbar spinal stenosis patients: part B. Preoperative versus postoperative gait variability

International Nuclear Information System (INIS)

Papadakis, N C; Christakis, D G; Tzagarakis, G N; Chlouverakis, G I; Kampanis, N A; Stergiopoulos, K N; Katonis, P G

2009-01-01

The objective of this study was to assess the gait variability of lumbar spinal stenosis (LSS) patients and to evaluate its postoperative progression. The hypothesis was that LSS patients' preoperative gait variability in the frequency domain was higher than the corresponding postoperative. A tri-axial accelerometer sensor was used for the gait measurement and a spectral differential entropy algorithm was used to measure the gait variability. Twelve subjects with LSS were measured before and after surgery. Preoperative measurements were performed 2 days before surgery. Postoperative measurements were performed 6 and 12 months after surgery. Preoperative gait variability was higher than the corresponding postoperative. Also, in most cases, gait variability appeared to decrease throughout the year

Independent influence of gait speed and step length on stability and fall risk.

Science.gov (United States)

Espy, D D; Yang, F; Bhatt, T; Pai, Y-C

2010-07-01

With aging, individuals' gaits become slower and their steps shorter; both are thought to improve stability against balance threats. Recent studies have shown that shorter step lengths, which bring the center of mass (COM) closer to the leading foot, improve stability against slip-related falls. However, a slower gait, hence lower COM velocity, does the opposite. Due to the inherent coupling of step length and speed in spontaneous gait, the extent to which the benefit of shorter steps can offset the slower speed is unknown. The purpose of this study was to investigate, through decoupling, the independent effects of gait speed and step length on gait stability and the likelihood of slip-induced falls. Fifty-seven young adults walked at one of three target gait patterns, two of equal speed and two of equal step length; at a later trial, they encountered an unannounced slip. The results supported our hypotheses that faster gait as well as shorter steps each ameliorates fall risk when a slip is encountered. This appeared to be attributable to the maintenance of stability from slip initiation to liftoff of the recovery foot during the slip. Successful decoupling of gait speed from step length reveals for the first time that, although slow gait in itself leads to instability and falls (a one-standard-deviation decrease in gait speed increases the odds of fall by 4-fold), this effect is offset by the related decrease in step length (the same one-standard-deviation decrease in step length lowers fall risk by 6 times). Copyright © 2010 Elsevier B.V. All rights reserved.

Subjects with hip osteoarthritis show distinctive patterns of trunk movements during gait-a body-fixed-sensor based analysis

NARCIS (Netherlands)

Reininga, Inge H. F.; Stevens, Martin; Wagenmakers, Robert; Bulstra, Sjoerd K.; Groothoff, Johan W.; Zijlstra, Wiebren

2012-01-01

Background: Compensatory trunk movements during gait, such as a Duchenne limp, are observed frequently in subjects with osteoarthritis of the hip, yet angular trunk movements are seldom included in clinical gait assessments. Hence, the objective of this study was to quantify compensatory trunk

EFFECTS OF PHYSICAL REHABILITATION INTEGRATED WITH RHYTHMIC AUDITORY STIMULATION ON SPATIO-TEMPORAL AND KINEMATIC PARAMETERS OF GAIT IN PARKINSON’S DISEASE

Directory of Open Access Journals (Sweden)

Massimiliano Pau

2016-08-01

Full Text Available Movement rehabilitation by means of physical therapy represents an essential tool in the management of gait disturbances induced by Parkinson’s disease (PD. In this context, the use of Rhythmic Auditory Stimulation (RAS has been proven useful in improving several spatio-temporal parameters, but concerning its effect on gait patterns scarce information is available from a kinematic viewpoint. In this study we used three-dimensional gait analysis based on optoelectronic stereophotogrammetry to investigate the effects of 5 weeks of intensive rehabilitation, which included gait training integrated with RAS on 26 individuals affected by PD (age 70.4±11.1, Hoehn & Yahr 1-3. Gait kinematics was assessed before and at the end of the rehabilitation period and after a three-month follow-up, using concise measures (Gait Profile Score and Gait Variable Score, GPS and GVS, respectively, which are able to describe the deviation from a physiologic gait pattern. The results confirm the effectiveness of gait training assisted by RAS in increasing speed and stride length, in regularizing cadence and correctly reweighting swing/stance phase duration. Moreover, an overall improvement of gait quality was observed, as demonstrated by the significant reduction of the GPS value, which was created mainly through significant decreases in the GVS score associated with the hip flexion-extension movement. Future research should focus on investigating kinematic details to better understand the mechanisms underlying gait disturbances in people with PD and the effects of RAS, with the aim of finding new or improving current rehabilitative treatments.

Influence of velocity on variability in gait kinematics: implications for recognition in forensic science.

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Yang, Sylvia X M; Larsen, Peter K; Alkjaer, Tine; Lynnerup, Niels; Simonsen, Erik B

2014-09-01

Closed circuit television (CCTV) footage is often available from crime scenes and may be used to compare perpetrators with suspects. Usually, the footage comprises incomplete gait cycles at different velocities, making gait pattern identification from crimes difficult. This study investigated the concurrence of joint angles throughout a gait cycle at three different velocities (3.0, 4.5, 6.0 km/h). Six datasets at each velocity were collected from 16 men. A variability range VR throughout the gait cycle at each velocity for each joint angle for each person was calculated. The joint angles at each velocity were compared pairwise, and whenever this showed values within the VR of this velocity, the case was positive. By adding the positives throughout the gait cycle, phases with high and low concurrences were located; peak concurrence was observed at mid-stance phase. Striving for the same velocity for the suspect and perpetrator is recommended. © 2014 American Academy of Forensic Sciences.

Bipedal gait model for precise gait recognition and optimal triggering in foot drop stimulator: a proof of concept.

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Shaikh, Muhammad Faraz; Salcic, Zoran; Wang, Kevin I-Kai; Hu, Aiguo Patrick

2018-03-10

Electrical stimulators are often prescribed to correct foot drop walking. However, commercial foot drop stimulators trigger inappropriately under certain non-gait scenarios. Past researches addressed this limitation by defining stimulation control based on automaton of a gait cycle executed by foot drop of affected limb/foot only. Since gait is a collaborative activity of both feet, this research highlights the role of normal foot for robust gait detection and stimulation triggering. A novel bipedal gait model is proposed where gait cycle is realized as an automaton based on concurrent gait sub-phases (states) from each foot. The input for state transition is fused information from feet-worn pressure and inertial sensors. Thereafter, a bipedal gait model-based stimulation control algorithm is developed. As a feasibility study, bipedal gait model and stimulation control are evaluated in real-time simulation manner on normal and simulated foot drop gait measurements from 16 able-bodied participants with three speed variations, under inappropriate triggering scenarios and with foot drop rehabilitation exercises. Also, the stimulation control employed in commercial foot drop stimulators and single foot gait-based foot drop stimulators are compared alongside. Gait detection accuracy (98.9%) and precise triggering under all investigations prove bipedal gait model reliability. This infers that gait detection leveraging bipedal periodicity is a promising strategy to rectify prevalent stimulation triggering deficiencies in commercial foot drop stimulators. Graphical abstract Bipedal information-based gait recognition and stimulation triggering.

Effects of conventional overground gait training and a gait trainer with partial body weight support on spatiotemporal gait parameters of patients after stroke.

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Park, Byoung-Sun; Kim, Mee-Young; Lee, Lim-Kyu; Yang, Seung-Min; Lee, Won-Deok; Noh, Ji-Woong; Shin, Yong-Sub; Kim, Ju-Hyun; Lee, Jeong-Uk; Kwak, Taek-Yong; Lee, Tae-Hyun; Kim, Ju-Young; Kim, Junghwan

2015-05-01

[Purpose] The purpose of this study was to confirm the effects of both conventional overground gait training (CGT) and a gait trainer with partial body weight support (GTBWS) on spatiotemporal gait parameters of patients with hemiparesis following chronic stroke. [Subjects and Methods] Thirty stroke patients were alternately assigned to one of two treatment groups, and both groups underwent CGT and GTBWS. [Results] The functional ambulation classification on the affected side improved significantly in the CGT and GTBWS groups. Walking speed also improved significantly in both groups. [Conclusion] These results suggest that the GTBWS in company with CGT may be, in part, an effective method of gait training for restoring gait ability in patients after a stroke.

Control of impact loading during distracted running before and after gait retraining in runners.

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Cheung, Roy T H; An, Winko W; Au, Ivan P H; Zhang, Janet H; Chan, Zoe Y S; MacPhail, Aislinn J

2018-07-01

Gait retraining using visual biofeedback has been reported to reduce impact loading in runners. However, most of the previous studies did not adequately examine the level of motor learning after training, as the modified gait pattern was not tested in a dual-task condition. Hence, this study sought to compare the landing peak positive acceleration (PPA) and vertical loading rates during distracted running before and after gait retraining. Sixteen recreational runners underwent a two-week visual biofeedback gait retraining program for impact loading reduction, with feedback on the PPA measured at heel. In the evaluation of PPA and vertical loading rates before and after the retraining, the participants performed a cognitive and verbal counting task while running. Repeated measures ANOVA indicated a significant interaction between feedback and training on PPA (F = 4.642; P = 0.048) but not vertical loading rates (F > 1.953; P > 0.067). Pairwise comparisons indicated a significantly lower PPA and vertical loading rates after gait retraining (P  0.68). Visual feedback after gait retraining reduced PPA and vertical loading rates during distracted running (P  0.36). Gait retraining is effective in lowering impact loading even when the runners are distracted. In dual-task situation, visual biofeedback provided beneficial influence on kinetics control after gait retraining.

Effects of physiotherapy treatment on knee osteoarthritis gait data using principal component analysis.

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Gaudreault, Nathaly; Mezghani, Neila; Turcot, Katia; Hagemeister, Nicola; Boivin, Karine; de Guise, Jacques A

2011-03-01

Interpreting gait data is challenging due to intersubject variability observed in the gait pattern of both normal and pathological populations. The objective of this study was to investigate the impact of using principal component analysis for grouping knee osteoarthritis (OA) patients' gait data in more homogeneous groups when studying the effect of a physiotherapy treatment. Three-dimensional (3D) knee kinematic and kinetic data were recorded during the gait of 29 participants diagnosed with knee OA before and after they received 12 weeks of physiotherapy treatment. Principal component analysis was applied to extract groups of knee flexion/extension, adduction/abduction and internal/external rotation angle and moment data. The treatment's effect on parameters of interest was assessed using paired t-tests performed before and after grouping the knee kinematic data. Increased quadriceps and hamstring strength was observed following treatment (Pphysiotherapy on gait mechanics of knee osteoarthritis patients may be masked or underestimated if kinematic data are not separated into more homogeneous groups when performing pre- and post-treatment comparisons. Copyright © 2010 Elsevier Ltd. All rights reserved.

[Development of a gait trainer with regulated servo-drive for rehabilitation of locomotor disabled patients].

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Uhlenbrock, D; Sarkodie-Gyan, T; Reiter, F; Konrad, M; Hesse, S

1997-01-01

The aim of the present study was to develop a new gait trainer for the rehabilitation of non-ambulatory patients. For the simulation of the gait phase, we used a commercially available fitness trainer (Fast Track) with two foot plates moving in an alternating fashion and connected to a servo-controlled propulsion system providing the necessary support for the movement depending on the patient's impairment level. To compensate deficient equilibrium reflexes, the patient was suspended in a harness capable of supporting some of his/her weight. Video analysis of gait and the kinesiological EMG were used to assess the pattern of movement and the corresponding muscle activity, which were then evaluated in healthy subjects, spinal cord injured and stroke patients and compared with walking on the flat or on a treadmill. Walking on the gait trainer was characterised by a symmetrical, sinusoidal movement of lower amplitude than in normal gait. The EMG showed a low activity of the tibialis anterior muscle, while the antigravity muscles were clearly activated by the gait trainer during the stance phase. In summary, the new gait trainer generates a symmetrical gait-like movement, promoting weight acceptance in the stance phase, which is important for the restoration of walking ability.

Towards a Passive Low-Cost In-Home Gait Assessment System for Older Adults

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Wang, Fang; Stone, Erik; Skubic, Marjorie; Keller, James M.; Abbott, Carmen; Rantz, Marilyn

2013-01-01

In this paper, we propose a webcam-based system for in-home gait assessment of older adults. A methodology has been developed to extract gait parameters including walking speed, step time and step length from a three-dimensional voxel reconstruction, which is built from two calibrated webcam views. The gait parameters are validated with a GAITRite mat and a Vicon motion capture system in the lab with 13 participants and 44 tests, and again with GAITRite for 8 older adults in senior housing. An excellent agreement with intra-class correlation coefficients of 0.99 and repeatability coefficients between 0.7% and 6.6% was found for walking speed, step time and step length given the limitation of frame rate and voxel resolution. The system was further tested with 10 seniors in a scripted scenario representing everyday activities in an unstructured environment. The system results demonstrate the capability of being used as a daily gait assessment tool for fall risk assessment and other medical applications. Furthermore, we found that residents displayed different gait patterns during their clinical GAITRite tests compared to the realistic scenario, namely a mean increase of 21% in walking speed, a mean decrease of 12% in step time, and a mean increase of 6% in step length. These findings provide support for continuous gait assessment in the home for capturing habitual gait. PMID:24235111

Single-task and dual-task tandem gait test performance after concussion.

Science.gov (United States)

Howell, David R; Osternig, Louis R; Chou, Li-Shan

2017-07-01

To compare single-task and dual-task tandem gait test performance between athletes after concussion with controls on observer-timed, spatio-temporal, and center-of-mass (COM) balance control measurements. Ten participants (19.0±5.5years) were prospectively identified and completed a tandem gait test protocol within 72h of concussion and again 1 week, 2 weeks, 1 month, and 2 months post-injury. Seven uninjured controls (20.0±4.5years) completed the same protocol in similar time increments. Tandem gait test trials were performed with (dual-task) and without (single-task) concurrently performing a cognitive test as whole-body motion analysis was performed. Outcome variables included test completion time, average tandem gait velocity, cadence, and whole-body COM frontal plane displacement. Concussion participants took significantly longer to complete the dual-task tandem gait test than controls throughout the first 2 weeks post-injury (mean time=16.4 [95% CI: 13.4-19.4] vs. 10.1 [95% CI: 6.4-13.7] seconds; p=0.03). Single-task tandem gait times were significantly lower 72h post-injury (p=0.04). Dual-task cadence was significantly lower for concussion participants than controls (89.5 [95% CI: 68.6-110.4] vs. 127.0 [95% CI: 97.4-156.6] steps/minute; p=0.04). Moderately-high to high correlations between tandem gait test time and whole-body COM medial-lateral displacement were detected at each time point during dual-task gait (r s =0.70-0.93; p=0.03-0.001). Adding a cognitive task during the tandem gait test resulted in longer detectable deficits post-concussion compared to the traditional single-task tandem gait test. As a clinical tool to assess dynamic motor function, tandem gait may assist with return to sport decisions after concussion. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Influence of moderate training on gait and work capacity of fibromyalgia patients: a preliminary field study.

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Tiidus, Peter M; Pierrynowski, Michael; Dawson, Kimberley A

2002-12-01

This field study examined the influence of moderate intensity training on gait patterns and work capacity of individuals with fibromyalgia syndrome (FS). FS is a chronic condition of unknown etiology, characterized by muscle tenderness, pain and stiffness and often accompanied by depression and fatigue which seems to occur primarily in middle aged females. There is no known cure for FS but treatment often includes a prescription of mild exercise. Few studies have evaluated the effectiveness of mild exercise on work capacity and gait patterns in FS patients. Participants were 14 females (age 47.0 ± 7.6 y) who participated in a 10 wk community based aerobic, strength and stretching program designed for FS individuals. Subjects were evaluated pre- and post-program and at a 2 month follow up. Work capacity was estimated by a sub-maximal PWC 170 cycle ergometer test and a Borg perceived exertion scale. Gait was assessed using OptoTrack three dimensional kinematics with 16 channel analogue data acquisition system. Trunk flexibility was also assessed. No significant change in estimated work capacity or flexibility was seen between pre- post- and follow up times. Nevertheless, a significant increase in self selected walking speed (p gait pattern that was sustained in the follow up testing was noted. We had previously also reported a significant improvement in muscle pain and other fibromyalgia symptoms in this population consequent to the training program. It was concluded that mild exercise training that does not influence work capacity or trunk flexibility can nevertheless positively influence gait mechanics and fibromyalgia symptoms in female FS patients.

Super Memory Bros.: going from mirror patterns to concordant patterns via similarity enhancements.

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Ozubko, Jason D; Joordens, Steve

2008-12-01

When memory is contrasted for stimuli belonging to distinct stimulus classes, one of two patterns is observed: a mirror pattern, in which one stimulus gives rise to higher hits but lower false alarms (e.g., the frequency-based mirror effect) or a concordant pattern, in which one stimulus class gives rise both to higher hits and to higher false alarms (e.g., the pseudoword effect). On the basis of the dual-process account proposed by Joordens and Hockley (2000), we predict that mirror patterns occur when one stimulus class is more familiar and less distinctive than another, whereas concordant patterns occur when one stimulus class is more familiar than another. We tested these assumptions within a video game paradigm using novel stimuli that allow manipulations in terms of distinctiveness and familiarity (via similarity). When more distinctive, less familiar items are contrasted with less distinctive, more familiar items, a mirror pattern is observed. Systematically enhancing the familiarity of stimuli transforms the mirror pattern to a concordant pattern as predicted. Although our stimuli differ considerably from those used in examinations of the frequency-based mirror effect and the pseudoword effect, the implications of our findings with respect to those phenomena are also discussed.

Swimming with multiple propulsors: measurement and comparison of swimming gaits in three species of neotropical cichlids.

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Feilich, Kara L

2017-11-15

Comparative studies of fish swimming have been limited by the lack of quantitative definitions of fish gaits. Traditionally, steady swimming gaits have been defined categorically by the fin or region of the body that is used as the main propulsor and named after major fish clades (e.g. carangiform, anguilliform, balistiform, labriform). This method of categorization is limited by the lack of explicit measurements, the inability to incorporate contributions of multiple propulsors and the inability to compare gaits across different categories. I propose an alternative framework for the definition and comparison of fish gaits based on the propulsive contribution of each structure (body and/or fin) being used as a propulsor relative to locomotor output, and demonstrate the effectiveness of this framework by comparing three species of neotropical cichlids with different body shapes. This approach is modular with respect to the number of propulsors considered, flexible with respect to the definition of the propulsive inputs and the locomotor output of interest, and designed explicitly to handle combinations of propulsors. Using this approach, gait can be defined as a trajectory through propulsive space, and gait transitions can be defined as discontinuities in the gait trajectory. By measuring and defining gait in this way, patterns of clustering corresponding to existing categorical definitions of gait may emerge, and gaits can be rigorously compared across categories. © 2017. Published by The Company of Biologists Ltd.

Relationship between physical function and biomechanical gait patterns in boys with haemophilia.

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Stephensen, D; Taylor, S; Bladen, M; Drechsler, W I

2016-11-01

The World Federation of Haemophilia recommends joint and muscle health is evaluated using X-ray and magnetic resonance imaging, together with clinical examination scores. To date, inclusion of performance-based functional activities to monitor children with the condition has received little attention. To evaluate test-retest repeatability of physical function tests and quantify relationships between physical function, lower limb muscle strength and gait patterns in young boys with haemophilia. Timed 6-minute walk, timed up and down stairs, timed single leg stance, muscle strength of the knee extensors, ankle dorsi and plantar flexors, together with joint biomechanics during level walking were collected from 21 boys aged 6-12 years with severe haemophilia. Measures of physical function and recording of muscle strength with a hand-held myometer were repeatable (ICC > 0.78). Distances walked in six minutes, time taken to go up and down a flight of stairs and lower limb muscle strength correlated closely with ankle range of motion, together with peak knee flexion and ankle dorsi and plantarflexion moments during walking (P biomechanical joint function, and hence might serve as a basis for the clinical monitoring of physical function outcomes in children with haemophilia. © 2016 John Wiley & Sons Ltd.

Balzac and human gait analysis.

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Collado-Vázquez, S; Carrillo, J M

2015-05-01

People have been interested in movement analysis in general, and gait analysis in particular, since ancient times. Aristotle, Hippocrates, Galen, Leonardo da Vinci and Honoré de Balzac all used observation to analyse the gait of human beings. The purpose of this study is to compare Honoré de Balzac's writings with a scientific analysis of human gait. Honoré de Balzac's Theory of walking and other works by that author referring to gait. Honoré de Balzac had an interest in gait analysis, as demonstrated by his descriptions of characters which often include references to their way of walking. He also wrote a treatise entitled Theory of walking (Théorie de la demarche) in which he employed his keen observation skills to define gait using a literary style. He stated that the walking process is divided into phases and listed the factors that influence gait, such as personality, mood, height, weight, profession and social class, and also provided a description of the correct way of walking. Balzac considered gait analysis to be very important and this is reflected in both his character descriptions and Theory of walking, his analytical observation of gait. In our own technology-dominated times, this serves as a reminder of the importance of observation. Copyright © 2011 Sociedad Española de Neurología. Published by Elsevier España, S.L.U. All rights reserved.

Increased gait unsteadiness in community-dwelling elderly fallers

Science.gov (United States)

Hausdorff, J. M.; Edelberg, H. K.; Mitchell, S. L.; Goldberger, A. L.; Wei, J. Y.

1997-01-01

OBJECTIVE: To test the hypothesis that quantitative measures of gait unsteadiness are increased in community-dwelling elderly fallers. STUDY DESIGN: Retrospective, case-control study. SETTING: General community. PARTICIPANTS: Thirty-five community-dwelling elderly subjects older than 70 years of age who were capable of ambulating independently for 6 minutes were categorized as fallers (age, 82.2 +/- 4.9 yrs [mean +/- SD]; n = 18) and nonfallers (age, 76.5 +/- 4.0 yrs; n = 17) based on history; 22 young (age, 24.6 +/- 1.9 yrs), healthy subjects also participated as a second reference group. MAIN OUTCOME MEASURES: Stride-to-stride variability (standard deviation and coefficient of variation) of stride time, stance time, swing time, and percent stance time measured during a 6-minute walk. RESULTS: All measures of gait variability were significantly greater in the elderly fallers compared with both the elderly nonfallers and the young subjects (p elderly fallers was similar to that of the nonfallers. There were little or no differences in the variability measures of the elderly nonfallers compared with the young subjects. CONCLUSIONS: Stride-to-stride temporal variations of gait are relatively unchanged in community-dwelling elderly nonfallers, but are significantly increased in elderly fallers. Quantitative measurement of gait unsteadiness may be useful in assessing fall risk in the elderly.

Single-Task and Dual-Task Gait Among Collegiate Athletes of Different Sport Classifications: Implications for Concussion Management.

Science.gov (United States)

Howell, David R; Oldham, Jessie R; DiFabio, Melissa; Vallabhajosula, Srikant; Hall, Eric E; Ketcham, Caroline J; Meehan, William P; Buckley, Thomas A

2017-02-01

Gait impairments have been documented following sport-related concussion. Whether preexisting gait pattern differences exist among athletes who participate in different sport classifications, however, remains unclear. Dual-task gait examinations probe the simultaneous performance of everyday tasks (ie, walking and thinking), and can quantify gait performance using inertial sensors. The purpose of this study was to compare the single-task and dual-task gait performance of collision/contact and noncontact athletes. A group of collegiate athletes (n = 265) were tested before their season at 3 institutions (mean age= 19.1 ± 1.1 years). All participants stood still (single-task standing) and walked while simultaneously completing a cognitive test (dual-task gait), and completed walking trials without the cognitive test (single-task gait). Spatial-temporal gait parameters were compared between collision/contact and noncontact athletes using MANCOVAs; cognitive task performance was compared using ANCOVAs. No significant single-task or dual-task gait differences were found between collision/contact and noncontact athletes. Noncontact athletes demonstrated higher cognitive task accuracy during single-task standing (P = .001) and dual-task gait conditions (P = .02) than collision/contact athletes. These data demonstrate the utility of a dual-task gait assessment outside of a laboratory and suggest that preinjury cognitive task performance during dual-tasks may differ between athletes of different sport classifications.

An accelerometric measure of the gait pattern in horses after the administration of sublingual detomidine.

Science.gov (United States)

López-Sanromán, F J; de la Riva Andrés, S; Holmbak-Petersen, R; Pérez-Nogués, M; Forés Jackson, P; Santos González, M

2014-10-01

The locomotor pattern alterations produced after the administration of a sublingual detomidine gel was measured by an accelerometric method in horses. Using a randomized two-way crossover design, all animals (n = 6) randomly received either detomidine gel or a placebo administered sublingually. A triaxial accelerometric device was used for gait assessment 15 minutes before (baseline) and every 10 minutes after each treatment for a period of 180 minutes. Eight different parameters were calculated, including speed, stride frequency, stride length, regularity, dorsoventral, propulsion, mediolateral, and total power. Force of acceleration and the three components of power were also calculated. Significant statistical differences were observed between groups in all the parameters but stride length. The majority of significant changes started between 30 and 70 minutes after drug administration and lasted for 160 minutes. This route of administration is definitely useful in horses in which a prolonged sedation is required, with stability being a major concern. Copyright © 2014 Elsevier Ltd. All rights reserved.

The contribution of a central pattern generator in a reflex-based neuromuscular model

Science.gov (United States)

Dzeladini, Florin; van den Kieboom, Jesse; Ijspeert, Auke

2014-01-01

Although the concept of central pattern generators (CPGs) controlling locomotion in vertebrates is widely accepted, the presence of specialized CPGs in human locomotion is still a matter of debate. An interesting numerical model developed in the 90s’ demonstrated the important role CPGs could play in human locomotion, both in terms of stability against perturbations, and in terms of speed control. Recently, a reflex-based neuro-musculo-skeletal model has been proposed, showing a level of stability to perturbations similar to the previous model, without any CPG components. Although exhibiting striking similarities with human gaits, the lack of CPG makes the control of speed/step length in the model difficult. In this paper, we hypothesize that a CPG component will offer a meaningful way of controlling the locomotion speed. After introducing the CPG component in the reflex model, and taking advantage of the resulting properties, a simple model for gait modulation is presented. The results highlight the advantages of a CPG as feedforward component in terms of gait modulation. PMID:25018712

The Contribution of a Central Pattern Generator in a Reflex-Based Neuromuscular Model

Directory of Open Access Journals (Sweden)

Florin eDzeladini

2014-06-01

Full Text Available Although the concept of central pattern generators (CPGs controlling locomotion in vertebrates is widely accepted, the presence of specialized CPGs in human locomotion is still a matter of debate. An interesting numerical model developed in the 90s' demonstrated the important role CPGs could play in human locomotion, both in terms of stability against perturbations, and in terms of speed control. Recently, a reflex-based neuro-musculo-skeletal model has been proposed, showing a level of stability to perturbations similar to the previous model, without any CPG components. Although exhibiting striking similarities with human gaits, the lack of CPG makes the control of speed/step length in the model difficult. In this paper, we hypothesize that a CPG component will offer a meaningful way of controlling the locomotion speed. After introducing the CPG component in the reflex model, and taking advantage of the resulting properties, a simple model for gait modulation is presented.The results highlight the advantages that a feedforward component can have in terms of gait modulation.

Gait characteristics after gait-oriented rehabilitation in chronic stroke.

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Peurala, Sinikka H; Titianova, Ekaterina B; Mateev, Plamen; Pitkänen, Kauko; Sivenius, Juhani; Tarkka, Ina M

2005-01-01

To assess the effects of rehabilitation in thirty-seven ambulatory patients with chronic stroke during three weeks in-patient rehabilitation period. In the intervention group, each patient received 75 min physiotherapy daily every workday including 20 minutes in the electromechanical gait trainer with body-weight support (BWS). In the control group, each patient participated in 45 min conventional physiotherapy daily. Motor ability was assessed with the first five items of the Modified Motor Assessment Scale (MMAS1-5) and ten meters walking speed. Spatio-temporal gait characteristics were recorded with an electrical walkway. The MMAS1-5 (pgait characteristics improved only in the intervention group, as seen in increased Functional Ambulation Profile score (p=0.023), velocity (p=0.023), the step lengths (affected side, p=0.011, non-affected side p=0.040), the stride lengths (p=0.018, p=0.006) and decreased step-time differential (p=0.043). Furthermore, all gait characteristics and other motor abilities remained in the discharge level at the six months in the intervention group. It appears that BWS training gives a long-lasting benefit in gait qualities even in chronic stroke patients.

Cognitive and motor dual task gait training improve dual task gait performance after stroke - A randomized controlled pilot trial.

Science.gov (United States)

Liu, Yan-Ci; Yang, Yea-Ru; Tsai, Yun-An; Wang, Ray-Yau

2017-06-22

This study investigated effects of cognitive and motor dual task gait training on dual task gait performance in stroke. Participants (n = 28) were randomly assigned to cognitive dual task gait training (CDTT), motor dual task gait training (MDTT), or conventional physical therapy (CPT) group. Participants in CDTT or MDTT group practiced the cognitive or motor tasks respectively during walking. Participants in CPT group received strengthening, balance, and gait training. The intervention was 30 min/session, 3 sessions/week for 4 weeks. Three test conditions to evaluate the training effects were single walking, walking while performing cognitive task (serial subtraction), and walking while performing motor task (tray-carrying). Parameters included gait speed, dual task cost of gait speed (DTC-speed), cadence, stride time, and stride length. After CDTT, cognitive-motor dual task gait performance (stride length and DTC-speed) was improved (p = 0.021; p = 0.015). After MDTT, motor dual task gait performance (gait speed, stride length, and DTC-speed) was improved (p = 0.008; p = 0.008; p = 0.008 respectively). It seems that CDTT improved cognitive dual task gait performance and MDTT improved motor dual task gait performance although such improvements did not reach significant group difference. Therefore, different types of dual task gait training can be adopted to enhance different dual task gait performance in stroke.

Gait and Cognition in Parkinson’s Disease: Cognitive Impairment Is Inadequately Reflected by Gait Performance during Dual Task

Directory of Open Access Journals (Sweden)

Heiko Gaßner

2017-10-01

Full Text Available IntroductionCognitive and gait deficits are common symptoms in Parkinson’s disease (PD. Motor-cognitive dual tasks (DTs are used to explore the interplay between gait and cognition. However, it is unclear if DT gait performance is indicative for cognitive impairment. Therefore, the aim of this study was to investigate if cognitive deficits are reflected by DT costs of spatiotemporal gait parameters.MethodsCognitive function, single task (ST and DT gait performance were investigated in 67 PD patients. Cognition was assessed by the Montreal Cognitive Assessment (MoCA followed by a standardized, sensor-based gait test and the identical gait test while subtracting serial 3’s. Cognitive impairment was defined by a MoCA score <26. DT costs in gait parameters [(DT − ST/ST × 100] were calculated as a measure of DT effect on gait. Correlation analysis was used to evaluate the association between MoCA performance and gait parameters. In a linear regression model, DT gait costs and clinical confounders (age, gender, disease duration, motor impairment, medication, and depression were correlated to cognitive performance. In a subgroup analysis, we compared matched groups of cognitively impaired and unimpaired PD patients regarding differences in ST, DT, and DT gait costs.ResultsCorrelation analysis revealed weak correlations between MoCA score and DT costs of gait parameters (r/rSp ≤ 0.3. DT costs of stride length, swing time variability, and maximum toe clearance (|r/rSp| > 0.2 were included in a regression analysis. The parameters only explain 8% of the cognitive variance. In combination with clinical confounders, regression analysis showed that these gait parameters explained 30% of MoCA performance. Group comparison revealed strong DT effects within both groups (large effect sizes, but significant between-group effects in DT gait costs were not observed.ConclusionThese findings suggest that DT gait performance is not indicative

Similar impact of topological and dynamic noise on complex patterns

International Nuclear Information System (INIS)

Marr, Carsten; Huett, Marc-Thorsten

2006-01-01

Shortcuts in a regular architecture affect the information transport through the system due to the severe decrease in average path length. A fundamental new perspective in terms of pattern formation is the destabilizing effect of topological perturbations by processing distant uncorrelated information, similarly to stochastic noise. We study the functional coincidence of rewiring and noisy communication on patterns of binary cellular automata

Hybridization between multi-objective genetic algorithm and support vector machine for feature selection in walker-assisted gait.

Science.gov (United States)

Martins, Maria; Costa, Lino; Frizera, Anselmo; Ceres, Ramón; Santos, Cristina

2014-03-01

Walker devices are often prescribed incorrectly to patients, leading to the increase of dissatisfaction and occurrence of several problems, such as, discomfort and pain. Thus, it is necessary to objectively evaluate the effects that assisted gait can have on the gait patterns of walker users, comparatively to a non-assisted gait. A gait analysis, focusing on spatiotemporal and kinematics parameters, will be issued for this purpose. However, gait analysis yields redundant information that often is difficult to interpret. This study addresses the problem of selecting the most relevant gait features required to differentiate between assisted and non-assisted gait. For that purpose, it is presented an efficient approach that combines evolutionary techniques, based on genetic algorithms, and support vector machine algorithms, to discriminate differences between assisted and non-assisted gait with a walker with forearm supports. For comparison purposes, other classification algorithms are verified. Results with healthy subjects show that the main differences are characterized by balance and joints excursion in the sagittal plane. These results, confirmed by clinical evidence, allow concluding that this technique is an efficient feature selection approach. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Gait as evidence

DEFF Research Database (Denmark)

Lynnerup, Niels; Larsen, Peter Kastmand

2014-01-01

This study examines what in Denmark may constitute evidence based on forensic anthropological gait analyses, in the sense of pointing to a match (or not) between a perpetrator and a suspect, based on video and photographic imagery. Gait and anthropometric measures can be used when direct facial...

Gait retraining as part of the treatment programme for soldiers with ...

African Journals Online (AJOL)

Kathryn van Boom

Gait retraining, as a treatment for overuse injuries of the lower extremities is ... pressure (N/cm2) on the heels at 317 days follow-up (average,. SD 108). ... The running style (type of strike) was .... findings on strike patterns among soldiers.

Functional recovery of gait and joint kinematics after right hemispheric stroke

NARCIS (Netherlands)

Huitema, RB; Mulder, T; Brouwer, WH; Dekker, R; Postema, K; Hof, A.L.

2004-01-01

Objective: To gain insight into the relation between changes in gait patterns over time and functional recovery of walking ability in stroke patients. Design: Cohort study. Setting: Inpatient rehabilitation center of a university hospital in the Netherlands. Participants: Thirteen stroke patients

Transitions between three swimming gaits in Paramecium escape.

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Hamel, Amandine; Fisch, Cathy; Combettes, Laurent; Dupuis-Williams, Pascale; Baroud, Charles N

2011-05-03

Paramecium and other protists are able to swim at velocities reaching several times their body size per second by beating their cilia in an organized fashion. The cilia beat in an asymmetric stroke, which breaks the time reversal symmetry of small scale flows. Here we show that Paramecium uses three different swimming gaits to escape from an aggression, applied in the form of a focused laser heating. For a weak aggression, normal swimming is sufficient and produces a steady swimming velocity. As the heating amplitude is increased, a higher acceleration and faster swimming are achieved through synchronized beating of the cilia, which begin by producing oscillating swimming velocities and later give way to the usual gait. Finally, escape from a life-threatening aggression is achieved by a "jumping" gait, which does not rely on the cilia but is achieved through the explosive release of a group of trichocysts in the direction of the hot spot. Measurements through high-speed video explain the role of trichocysts in defending against aggressions while showing unexpected transitions in the swimming of microorganisms. These measurements also demonstrate that Paramecium optimizes its escape pattern by taking advantage of its inertia.

INFLUENCE OF MODERATE TRAINING ON GAIT AND WORK CAPACITY OF FIBROMYALGIA PATIENTS: A PRELIMINARY FIELD STUDY

Directory of Open Access Journals (Sweden)

Michael Pierrynowski

2002-12-01

Full Text Available This field study examined the influence of moderate intensity training on gait patterns and work capacity of individuals with fibromyalgia syndrome (FS. FS is a chronic condition of unknown etiology, characterized by muscle tenderness, pain and stiffness and often accompanied by depression and fatigue which seems to occur primarily in middle aged females. There is no known cure for FS but treatment often includes a prescription of mild exercise. Few studies have evaluated the effectiveness of mild exercise on work capacity and gait patterns in FS patients. Participants were 14 females (age 47.0± 7.6 y who participated in a 10 wk community based aerobic, strength and stretching program designed for FS individuals. Subjects were evaluated pre- and post-program and at a 2 month follow up. Work capacity was estimated by a sub-maximal PWC 170 cycle ergometer test and a Borg perceived exertion scale. Gait was assessed using OptoTrack three dimensional kinematics with 16 channel analogue data acquisition system. Trunk flexibility was also assessed. No significant change in estimated work capacity or flexibility was seen between pre- post- and follow up times. Nevertheless, a significant increase in self selected walking speed (p < 0.05 and a trend toward a more normal gait pattern that was sustained in the follow up testing was noted. We had previously also reported a significant improvement in muscle pain and other fibromyalgia symptoms in this population consequent to the training program. It was concluded that mild exercise training that does not influence work capacity or trunk flexibility can nevertheless positively influence gait mechanics and fibromyalgia symptoms in female FS patients

Motor coordination during gait after anterior cruciate ligament injury: a systematic review of the literature

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Gustavo Leporace

2013-08-01

Full Text Available To investigate the state of art about motor coordination during gait in patients with anterior cruciate ligament (ACL injury. Searches were carried out, limited from 1980 to 2010, in various databases with keywords related to motor coordination, gait and ACL injury. From the analysis of titles and applying the inclusion/exclusion criteria 24 studies were initially selected and, after reading the abstract, eight studies remained in the final analysis. ACL deficient patients tend to have a more rigid and less variable gait, while injured patients with ACL reconstruction have less rigid and more variable gait with respect to healthy individuals. The overall results suggest the existence of differences in motor coordination between the segments with intact and those with injured knee, regardless of ligament reconstruction. ACL injured patients present aspects related to the impairment of the capability to adapt the gait pattern to different environmental conditions, possibly leading to premature knee degeneration. However, the techniques used for biomechanical gait data processing are limited with respect to obtaining information that leads to the development of intervention strategies aimed at the rehabilitation of that injury, since it is not possible to identify the location within the gait cycle where the differences could be explained.

Change in gait after high tibial osteotomy: A systematic review and meta-analysis.

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Lee, Seung Hoon; Lee, O-Sung; Teo, Seow Hui; Lee, Yong Seuk

2017-09-01

We conducted a meta-analysis to analyze how high tibial osteotomy (HTO) changes gait and focused on the following questions: (1) How does HTO change basic gait variables? (2) How does HTO change the gait variables in the knee joint? Twelve articles were included in the final analysis. A total of 383 knees was evaluated. There were 237 open wedge (OW) and 143 closed wedge (CW) HTOs. There were 4 level II studies and 8 level III studies. All studies included gait analysis and compared pre- and postoperative values. One study compared CWHTO and unicompartmental knee arthroplasty (UKA), and another study compared CWHTO and OWHTO. Five studies compared gait variables with those of healthy controls. One study compared operated limb gait variables with those in the non-operated limb. Gait speed, stride length, knee adduction moment, and lateral thrust were major variables assessed in 2 or more studies. Walking speed increased and stride length was increased or similar after HTO compared to the preoperative value in basic gait variables. Knee adduction moment and lateral thrust were decreased after HTO compared to the preoperative knee joint gait variables. Change in co-contraction of the medial side muscle after surgery differed depending on the degree of frontal plane alignment. The relationship between change in knee adduction moment and change in mechanical axis angle was controversial. Based on our systematic review and meta-analysis, walking speed and stride length increased after HTO. Knee adduction moment and lateral thrust decreased after HTO compared to the preoperative values of gait variables in the knee joint. Copyright © 2017 Elsevier B.V. All rights reserved.

Similar Fracture Patterns in Human Nose and Gothic Cathedral.

Science.gov (United States)

Lee, Shu Jin; Tse, Kwong Ming; Lee, Heow Pueh

2015-10-01

This study proposes that the bony anatomy of the human nose and masonry structure of the Gothic cathedral are geometrically similar, and have common fracture patterns. We also aim to correlate the fracture patterns observed in patients' midface structures with those seen in the Gothic cathedral using computational approach. CT scans of 33 patients with facial fractures were examined and compared with computer simulations of both the Gothic cathedral and human nose. Three similar patterns were found: (1) Cracks of the nasal arch with crumpling of the vertical buttresses akin to the damage seen during minor earthquakes; (2) lateral deviation of the central nasal arch and collapse of the vertical buttresses akin to those due to lateral forces from wind and in major earthquakes; and (3) Central arch collapse seen as a result of collapse under excessive dead weight. Interestingly, the finding of occult nasal and septal fractures in the mandible fractures with absence of direct nasal trauma highlights the possibility of transmission of forces from the foundation to the arch leading to structural failure. It was also found that the structural buttresses of the Gothic cathedral delineate the vertical buttresses in the human midface structure. These morphologic similarities between the human nose and Gothic cathedral will serve as a basis to study the biomechanics of nasal fractures. Identification of structural buttresses in a skeletal structure has important implications for reconstruction as reestablishment of structural continuity restores normal anatomy and architectural stability of the human midface structure. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Coupled chaotic oscillators and their relation to a central pattern ...

Indian Academy of Sciences (India)

Abstract. Animal locomotion employs different periodic patterns known as animal gaits. In 1993, Collins and Stewart recognized that gaits possessed certain symmetries and characterized the gaits of quadrupeds and bipeds using permutation symmetry groups, which impose constraints on the locomotion center called the ...

The effect of virtual reality on gait variability.

Science.gov (United States)

Katsavelis, Dimitrios; Mukherjee, Mukul; Decker, Leslie; Stergiou, Nicholas

2010-07-01

Optic Flow (OF) plays an important role in human locomotion and manipulation of OF characteristics can cause changes in locomotion patterns. The purpose of the study was to investigate the effect of the velocity of optic flow on the amount and structure of gait variability. Each subject underwent four conditions of treadmill walking at their self-selected pace. In three conditions the subjects walked in an endless virtual corridor, while a fourth control condition was also included. The three virtual conditions differed in the speed of the optic flow displayed as follows--same speed (OFn), faster (OFf), and slower (OFs) than that of the treadmill. Gait kinematics were tracked with an optical motion capture system. Gait variability measures of the hip, knee and ankle range of motion and stride interval were analyzed. Amount of variability was evaluated with linear measures of variability--coefficient of variation, while structure of variability i.e., its organization over time, were measured with nonlinear measures--approximate entropy and detrended fluctuation analysis. The linear measures of variability, CV, did not show significant differences between Non-VR and VR conditions while nonlinear measures of variability identified significant differences at the hip, ankle, and in stride interval. In response to manipulation of the optic flow, significant differences were observed between the three virtual conditions in the following order: OFn greater than OFf greater than OFs. Measures of structure of variability are more sensitive to changes in gait due to manipulation of visual cues, whereas measures of the amount of variability may be concealed by adaptive mechanisms. Visual cues increase the complexity of gait variability and may increase the degrees of freedom available to the subject. Further exploration of the effects of optic flow manipulation on locomotion may provide us with an effective tool for rehabilitation of subjects with sensorimotor issues.

Effect of three cueing devices for people with Parkinson's disease with gait initiation difficulties.

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McCandless, Paula J; Evans, Brenda J; Janssen, Jessie; Selfe, James; Churchill, Andrew; Richards, Jim

2016-02-01

Freezing of gait (FOG) remains one of the most common debilitating aspects of Parkinson's disease and has been linked to injuries, falls and reduced quality of life. Although commercially available portable cueing devices exist claiming to assist with overcoming freezing; their immediate effectiveness in overcoming gait initiation failure is currently unknown. This study investigated the effects of three different types of cueing device in people with Parkinson's disease who experience freezing. Twenty participants with idiopathic Parkinson's disease who experienced freezing during gait but who were able to walk short distances indoors independently were recruited. At least three attempts at gait initiation were recorded using a 10 camera Qualisys motion analysis system and four force platforms. Test conditions were; Laser Cane, sound metronome, vibrating metronome, walking stick and no intervention. During testing 12 of the 20 participants had freezing episodes, from these participants 100 freezing and 91 non-freezing trials were recorded. Clear differences in the movement patterns were seen between freezing and non-freezing episodes. The Laser Cane was most effective cueing device at improving the forwards/backwards and side to side movement and had the least number of freezing episodes. The walking stick also showed significant improvements compared to the other conditions. The vibration metronome appeared to disrupt movement compared to the sound metronome at the same beat frequency. This study identified differences in the movement patterns between freezing episodes and non-freezing episodes, and identified immediate improvements during gait initiation when using the Laser Cane over the other interventions. Copyright © 2015. Published by Elsevier B.V.

Investigation of Time Series Representations and Similarity Measures for Structural Damage Pattern Recognition

Science.gov (United States)

Swartz, R. Andrew

2013-01-01

This paper investigates the time series representation methods and similarity measures for sensor data feature extraction and structural damage pattern recognition. Both model-based time series representation and dimensionality reduction methods are studied to compare the effectiveness of feature extraction for damage pattern recognition. The evaluation of feature extraction methods is performed by examining the separation of feature vectors among different damage patterns and the pattern recognition success rate. In addition, the impact of similarity measures on the pattern recognition success rate and the metrics for damage localization are also investigated. The test data used in this study are from the System Identification to Monitor Civil Engineering Structures (SIMCES) Z24 Bridge damage detection tests, a rigorous instrumentation campaign that recorded the dynamic performance of a concrete box-girder bridge under progressively increasing damage scenarios. A number of progressive damage test case datasets and damage test data with different damage modalities are used. The simulation results show that both time series representation methods and similarity measures have significant impact on the pattern recognition success rate. PMID:24191136

Investigation of Time Series Representations and Similarity Measures for Structural Damage Pattern Recognition

Directory of Open Access Journals (Sweden)

Wenjia Liu

2013-01-01

Full Text Available This paper investigates the time series representation methods and similarity measures for sensor data feature extraction and structural damage pattern recognition. Both model-based time series representation and dimensionality reduction methods are studied to compare the effectiveness of feature extraction for damage pattern recognition. The evaluation of feature extraction methods is performed by examining the separation of feature vectors among different damage patterns and the pattern recognition success rate. In addition, the impact of similarity measures on the pattern recognition success rate and the metrics for damage localization are also investigated. The test data used in this study are from the System Identification to Monitor Civil Engineering Structures (SIMCES Z24 Bridge damage detection tests, a rigorous instrumentation campaign that recorded the dynamic performance of a concrete box-girder bridge under progressively increasing damage scenarios. A number of progressive damage test case datasets and damage test data with different damage modalities are used. The simulation results show that both time series representation methods and similarity measures have significant impact on the pattern recognition success rate.

The Golden Ratio of Gait Harmony: Repetitive Proportions of Repetitive Gait Phases

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Marco Iosa

2013-01-01

Full Text Available In nature, many physical and biological systems have structures showing harmonic properties. Some of them were found related to the irrational number known as the golden ratio that has important symmetric and harmonic properties. In this study, the spatiotemporal gait parameters of 25 healthy subjects were analyzed using a stereophotogrammetric system with 25 retroreflective markers located on their skin. The proportions of gait phases were compared with , the value of which is about 1.6180. The ratio between the entire gait cycle and stance phase resulted in 1.620 ± 0.058, that between stance and the swing phase was 1.629 ± 0.173, and that between swing and the double support phase was 1.684 ± 0.357. All these ratios did not differ significantly from each other (, , repeated measure analysis of variance or from (, resp., t-tests. The repetitive gait phases of physiological walking were found in turn in repetitive proportions with each other, revealing an intrinsic harmonic structure. Harmony could be the key for facilitating the control of repetitive walking. Harmony is a powerful unifying factor between seemingly disparate fields of nature, including human gait.

Self-perceived gait stability modulates the effect of daily life gait quality on prospective falls in older adults

NARCIS (Netherlands)

Weijer, R H A; Hoozemans, M J M; van Dieën, J H; Pijnappels, M

2018-01-01

BACKGROUND: Quality of gait during daily life activities and perceived gait stability are both independent risk factors for future falls in older adults. RESEARCH QUESTION: We investigated whether perceived gait stability modulates the association between gait quality and falling in older adults.

Association of Dual-Task Gait With Incident Dementia in Mild Cognitive Impairment: Results From the Gait and Brain Study.

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Montero-Odasso, Manuel M; Sarquis-Adamson, Yanina; Speechley, Mark; Borrie, Michael J; Hachinski, Vladimir C; Wells, Jennie; Riccio, Patricia M; Schapira, Marcelo; Sejdic, Ervin; Camicioli, Richard M; Bartha, Robert; McIlroy, William E; Muir-Hunter, Susan

2017-07-01

Gait performance is affected by neurodegeneration in aging and has the potential to be used as a clinical marker for progression from mild cognitive impairment (MCI) to dementia. A dual-task gait test evaluating the cognitive-motor interface may predict dementia progression in older adults with MCI. To determine whether a dual-task gait test is associated with incident dementia in MCI. The Gait and Brain Study is an ongoing prospective cohort study of community-dwelling older adults that enrolled 112 older adults with MCI. Participants were followed up for 6 years, with biannual visits including neurologic, cognitive, and gait assessments. Data were collected from July 2007 to March 2016. Incident all-cause dementia was the main outcome measure, and single- and dual-task gait velocity and dual-task gait costs were the independent variables. A neuropsychological test battery was used to assess cognition. Gait velocity was recorded under single-task and 3 separate dual-task conditions using an electronic walkway. Dual-task gait cost was defined as the percentage change between single- and dual-task gait velocities: ([single-task gait velocity - dual-task gait velocity]/ single-task gait velocity) × 100. Cox proportional hazard models were used to estimate the association between risk of progression to dementia and the independent variables, adjusted for age, sex, education, comorbidities, and cognition. Among 112 study participants with MCI, mean (SD) age was 76.6 (6.9) years, 55 were women (49.1%), and 27 progressed to dementia (24.1%), with an incidence rate of 121 per 1000 person-years. Slow single-task gait velocity (gait cost while counting backward (HR, 3.79; 95% CI, 1.57-9.15; P = .003) and naming animals (HR, 2.41; 95% CI, 1.04-5.59; P = .04) were associated with dementia progression (incidence rate, 155 per 1000 person-years). The models remained robust after adjusting by baseline cognition except for dual-task gait cost when dichotomized. Dual

Is Freezing of Gait in Parkinson's Disease a Result of Multiple Gait Impairments? Implications for Treatment

Science.gov (United States)

Plotnik, Meir; Giladi, Nir; Hausdorff, Jeffrey M.

2012-01-01

Several gait impairments have been associated with freezing of gait (FOG) in patients with Parkinson's disease (PD). These include deteriorations in rhythm control, gait symmetry, bilateral coordination of gait, dynamic postural control and step scaling. We suggest that these seemingly independent gait features may have mutual interactions which, during certain circumstances, jointly drive the predisposed locomotion system into a FOG episode. This new theoretical framework is illustrated by the evaluation of the potential relationships between the so-called “sequence effect”, that is, impairments in step scaling, and gait asymmetry just prior to FOG. We further discuss what factors influence gait control to maintain functional gait. “Triggers”, for example, such as attention shifts or trajectory transitions, may precede FOG. We propose distinct categories of interventions and describe examples of existing work that support this idea: (a) interventions which aim to maintain a good level of locomotion control especially with respect to aspects related to FOG; (b) those that aim at avoiding FOG “triggers”; and (c) those that merely aim to escape from FOG once it occurs. The proposed theoretical framework sets the stage for testable hypotheses regarding the mechanisms that lead to FOG and may also lead to new treatment ideas. PMID:22288021

Gait disorders in the elderly and dual task gait analysis: a new approach for identifying motor phenotypes.

Science.gov (United States)

Auvinet, Bernard; Touzard, Claude; Montestruc, François; Delafond, Arnaud; Goeb, Vincent

2017-01-31

Gait disorders and gait analysis under single and dual-task conditions are topics of great interest, but very few studies have looked for the relevance of gait analysis under dual-task conditions in elderly people on the basis of a clinical approach. An observational study including 103 patients (mean age 76.3 ± 7.2, women 56%) suffering from gait disorders or memory impairment was conducted. Gait analysis under dual-task conditions was carried out for all patients. Brain MRI was performed in the absence of contra-indications. Three main gait variables were measured: walking speed, stride frequency, and stride regularity. For each gait variable, the dual task cost was computed and a quartile analysis was obtained. Nonparametric tests were used for all the comparisons (Wilcoxon, Kruskal-Wallis, Fisher or Chi 2 tests). Four clinical subgroups were identified: gait instability (45%), recurrent falls (29%), memory impairment (18%), and cautious gait (8%). The biomechanical severity of these subgroups was ordered according to walking speed and stride regularity under both conditions, from least to most serious as follows: memory impairment, gait instability, recurrent falls, cautious gait (p < 0.01 for walking speed, p = 0.05 for stride regularity). According to the established diagnoses of gait disorders, 5 main pathological subgroups were identified (musculoskeletal diseases (n = 11), vestibular diseases (n = 6), mild cognitive impairment (n = 24), central nervous system pathologies, (n = 51), and without diagnosis (n = 8)). The dual task cost for walking speed, stride frequency and stride regularity were different among these subgroups (p < 0.01). The subgroups mild cognitive impairment and central nervous system pathologies both showed together a higher dual task cost for each variable compared to the other subgroups combined (p = 0.01). The quartile analysis of dual task cost for stride frequency and stride regularity

Gait Is Associated with Cognitive Flexibility: A Dual-Tasking Study in Healthy Older People

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Markus A. Hobert

2017-05-01

Full Text Available Objectives: To analyze which gait parameters are primarily influenced by cognitive flexibility, and whether such an effect depends on the walking condition used.Design: Cross-sectional analysis.Setting: Tübingen evaluation of Risk factors for Early detection of Neurodegenerative Disorders.Participants: A total of 661 non-demented individuals (49–80 years.Measurements: A gait assessment with four conditions was performed: a 20 m walk at convenient speed (C, at fast speed (F, at fast speed while checking boxes (FB, and while subtracting serial 7s (FS. Seven gait parameters from a wearable sensor-unit (McRoberts, Netherlands were compared with delta Trail-Making-Test (dTMT values, which is a measure of cognitive flexibility. Walking strategies of good and poor dTMT performers were compared by evaluating the patterns of gait parameters across conditions.Results: Five parameters correlated significantly with the dTMT in the FS condition, two parameters in the F and FB condition, and none in the C condition. Overall correlations were relatively weak. Gait speed was the gait parameter that most strongly correlated with the dTMT (r2 = 7.4%. In good, but not poor, dTMT performers differences between FB and FS were significantly different in variability-associated gait parameters.Conclusion: Older individuals need cognitive flexibility to perform difficult walking conditions. This association is best seen in gait speed. New and particularly relevant for recognition and training of deficits is that older individuals with poor cognitive flexibility have obviously fewer resources to adapt to challenging walking conditions. Our findings partially explain gait deficits in older adults with poor cognitive flexibility.

The dual task effect on gait in adults with intellectual disabilities: is it predictive for falls?

Science.gov (United States)

Oppewal, Alyt; Hilgenkamp, Thessa I M

2017-09-03

Falling is an important health issue in adults with intellectual disabilities. Their cognitive and motor limitations may result in difficulties with dual tasking (walking and talking), which increases fall risk. Therefore, we assessed the dual task effect on gait in adults with intellectual disabilities, if this dual task effect is predictive for falls, and if this is more predictive than regular walking. Gait characteristics of 31 adults with intellectual disabilities without Down syndrome were assessed with the GAITRite at comfortable speed and during dual tasking (conversation). Falls were collected over a three-month follow-up period. During dual tasking, participants walked slower, with a lower cadence, increased stride time, and shorter stride lengths. They spend less time in swing and single support phase than at comfortable speed. Also swing and single support time became more variable. The dual task effect and walking at comfortable speed were not predictive for falls, although medium effect sizes were found. Dual tasking affects gait in adults with intellectual disabilities. This is an important finding for safe community participation, and must be considered while interacting with adults with intellectual disabilities during daily activities. Possible negative consequences of distractors should be kept in mind. More research is needed to better understand the predictive value of gait for falls. Implications for Rehabilitation Having a conversation while walking affects the gait pattern of adults with intellectual disabilities, possible negative consequences of distractors should be kept in mind. The dual task effect on the width of the gait pattern and stride time variability had the largest effect sizes with future falls, this potential relationship should be kept in mind in clinical practice. The dual task effect on gait is important to consider with regard to safe community participation. Future studies are needed to better understand the predictive

Gait re-education based on the Bobath concept in two patients with hemiplegia following stroke.

Science.gov (United States)

Lennon, S

2001-03-01

This case report describes the use of gait re-education based on the Bobath concept to measure the changes that occurred in the gait of 2 patients with hemiplegia who were undergoing outpatient physical therapy. One patient ("NM"), a 65-year-old woman, was referred for physical therapy 6 weeks following a right cerebrovascular accident. She attended 30 therapy sessions over a 15-week period. The other patient ("SA"), a 71-year-old woman, was referred for physical therapy 7 weeks following a left cerebrovascular accident. She attended 28 therapy sessions over a 19-week period. Clinical indexes of impairment and disability and 3-dimensional gait data were obtained at the start of treatment and at discharge. Therapy was based on the Bobath concept. At discharge, NM demonstrated improvements in her hip and knee movements, reduced tone, and improved mobility. At discharge, SA demonstrated improved mobility. During gait, both patients demonstrated more normal movement patterns at the level of the pelvis, the knee, and the ankle in the sagittal plane. SA also demonstrated an improvement in hip extension. These cases demonstrate that recovery of more normal movement patterns and functional ability can be achieved following a cardiovascular accident and provide insight into the clinical decision making of experienced practitioners using Bobath's concept.

Characterizing multisegment foot kinematics during gait in diabetic foot patients

Directory of Open Access Journals (Sweden)

Denti Paolo

2009-10-01

Full Text Available Abstract Background The prevalence of diabetes mellitus has reached epidemic proportions, this condition may result in multiple and chronic invalidating long term complications. Among these, the diabetic foot, is determined by the simultaneous presence of both peripheral neuropathy and vasculopathy that alter the biomechanics of the foot with the formation of callosity and ulcerations. To diagnose and treat the diabetic foot is crucial to understand the foot complex kinematics. Most of gait analysis protocols represent the entire foot as a rigid body connected to the shank. Nevertheless the existing multisegment models cannot completely decipher the impairments associated with the diabetic foot. Methods A four segment foot and ankle model for assessing the kinematics of the diabetic foot was developed. Ten normal subjects and 10 diabetics gait patterns were collected and major sources of variability were tested. Repeatability analysis was performed both on a normal and on a diabetic subject. Direct skin marker placement was chosen in correspondence of 13 anatomical landmarks and an optoelectronic system was used to collect the data. Results Joint rotation normative bands (mean plus/minus one standard deviation were generated using the data of the control group. Three representative strides per subject were selected. The repeatability analysis on normal and pathological subjects results have been compared with literature and found comparable. Normal and pathological gait have been compared and showed major statistically significant differences in the forefoot and midfoot dorsi-plantarflexion. Conclusion Even though various biomechanical models have been developed so far to study the properties and behaviour of the foot, the present study focuses on developing a methodology for the functional assessment of the foot-ankle complex and for the definition of a functional model of the diabetic neuropathic foot. It is, of course, important to evaluate

The Combined Effects of Body Weight Support and Gait Speed on Gait Related Muscle Activity: A Comparison between Walking in the Lokomat Exoskeleton and Regular Treadmill Walking

Science.gov (United States)

Van Kammen, Klaske; Boonstra, Annemarijke; Reinders-Messelink, Heleen; den Otter, Rob

2014-01-01

Background For the development of specialized training protocols for robot assisted gait training, it is important to understand how the use of exoskeletons alters locomotor task demands, and how the nature and magnitude of these changes depend on training parameters. Therefore, the present study assessed the combined effects of gait speed and body weight support (BWS) on muscle activity, and compared these between treadmill walking and walking in the Lokomat exoskeleton. Methods Ten healthy participants walked on a treadmill and in the Lokomat, with varying levels of BWS (0% and 50% of the participants’ body weight) and gait speed (0.8, 1.8, and 2.8 km/h), while temporal step characteristics and muscle activity from Erector Spinae, Gluteus Medius, Vastus Lateralis, Biceps Femoris, Gastrocnemius Medialis, and Tibialis Anterior muscles were recorded. Results The temporal structure of the stepping pattern was altered when participants walked in the Lokomat or when BWS was provided (i.e. the relative duration of the double support phase was reduced, and the single support phase prolonged), but these differences normalized as gait speed increased. Alternations in muscle activity were characterized by complex interactions between walking conditions and training parameters: Differences between treadmill walking and walking in the exoskeleton were most prominent at low gait speeds, and speed effects were attenuated when BWS was provided. Conclusion Walking in the Lokomat exoskeleton without movement guidance alters the temporal step regulation and the neuromuscular control of walking, although the nature and magnitude of these effects depend on complex interactions with gait speed and BWS. If normative neuromuscular control of gait is targeted during training, it is recommended that very low speeds and high levels of BWS should be avoided when possible. PMID:25226302

Adaptive locomotor training on an end-effector gait robot: evaluation of the ground reaction forces in different training conditions.

Science.gov (United States)

Tomelleri, Christopher; Waldner, Andreas; Werner, Cordula; Hesse, Stefan

2011-01-01

The main goal of robotic gait rehabilitation is the restoration of independent gait. To achieve this goal different and specific patterns have to be practiced intensively in order to stimulate the learning process of the central nervous system. The gait robot G-EO Systems was designed to allow the repetitive practice of floor walking, stair climbing and stair descending. A novel control strategy allows training in adaptive mode. The force interactions between the foot and the ground were analyzed on 8 healthy volunteers in three different conditions: real floor walking on a treadmill, floor walking on the gait robot in passive mode, floor walking on the gait robot in adaptive mode. The ground reaction forces were measured by a Computer Dyno Graphy (CDG) analysis system. The results show different intensities of the ground reaction force across all of the three conditions. The intensities of force interactions during the adaptive training mode are comparable to the real walking on the treadmill. Slight deviations still occur in regard to the timing pattern of the forces. The adaptive control strategy comes closer to the physiological swing phase than the passive mode and seems to be a promising option for the treatment of gait disorders. Clinical trials will validate the efficacy of this new option in locomotor therapy on the patients. © 2011 IEEE

THE RELATION BETWEEN MILD LEG-LENGTH INEQUALITY AND ABLE-BODIED GAIT ASYMMETRY

Directory of Open Access Journals (Sweden)

Matthew K. Seeley

2010-12-01

Full Text Available The causes of able-bodied gait asymmetries are unclear. Mild ( 1 cm; n = 7. Statistically significant relationships were observed between LLI and the symmetry coefficient for knee joint moment (r = -0.48 and power (r = -0.51, and ankle joint moment (r = -0.41 and power (r = -0.42. Similarly, subjects with relatively large LLI exhibited significantly lower symmetry coefficients for knee joint moment (p = 0.40 and power (p = 0.35, and ankle joint moment (p = 0.40 and power (p = 0.22 than subjects with relatively small LLI. Degree of bilateral symmetry for knee and ankle joint kinetics appears to be related to LLI in able- bodied gait. This finding supports the idea that LLI is one cause of able-bodied gait asymmetries. Other factors, however, are also likely to contribute to these gait asymmetries; these may include other morphological asymmetries as well as asymmetrical neuromuscular input to the lower limb muscles

Association between stride time fractality and gait adaptability during unperturbed and asymmetric walking.

Science.gov (United States)

Ducharme, Scott W; Liddy, Joshua J; Haddad, Jeffrey M; Busa, Michael A; Claxton, Laura J; van Emmerik, Richard E A

2018-04-01

Human locomotion is an inherently complex activity that requires the coordination and control of neurophysiological and biomechanical degrees of freedom across various spatiotemporal scales. Locomotor patterns must constantly be altered in the face of changing environmental or task demands, such as heterogeneous terrains or obstacles. Variability in stride times occurring at short time scales (e.g., 5-10 strides) is statistically correlated to larger fluctuations occurring over longer time scales (e.g., 50-100 strides). This relationship, known as fractal dynamics, is thought to represent the adaptive capacity of the locomotor system. However, this has not been tested empirically. Thus, the purpose of this study was to determine if stride time fractality during steady state walking associated with the ability of individuals to adapt their gait patterns when locomotor speed and symmetry are altered. Fifteen healthy adults walked on a split-belt treadmill at preferred speed, half of preferred speed, and with one leg at preferred speed and the other at half speed (2:1 ratio asymmetric walking). The asymmetric belt speed condition induced gait asymmetries that required adaptation of locomotor patterns. The slow speed manipulation was chosen in order to determine the impact of gait speed on stride time fractal dynamics. Detrended fluctuation analysis was used to quantify the correlation structure, i.e., fractality, of stride times. Cross-correlation analysis was used to measure the deviation from intended anti-phasing between legs as a measure of gait adaptation. Results revealed no association between unperturbed walking fractal dynamics and gait adaptability performance. However, there was a quadratic relationship between perturbed, asymmetric walking fractal dynamics and adaptive performance during split-belt walking, whereby individuals who exhibited fractal scaling exponents that deviated from 1/f performed the poorest. Compared to steady state preferred walking

The Effect of Two Different Cognitive Tests on Gait Parameters during Dual Tasks in Healthy Postmenopausal Women

Directory of Open Access Journals (Sweden)

Magdalena Hagner-Derengowska

2016-01-01

Full Text Available Introduction. The paper aims to evaluate the influence of two different demanding cognitive tasks on gait parameters using BTS SMART system analysis. Patients and Methods. The study comprised 53 postmenopausal women aged 64.5 ± 6.7 years (range: 47–79. For every subject, gait analysis using a BTS SMART system was performed in a dual-task study design under three conditions: (I while walking only (single task, (II walking while performing a simultaneous simple cognitive task (SCT (dual task, and (III walking while performing a simultaneous complex cognitive task (CCT (dual task. Time-space parameters of gait pertaining to the length of a single support phase, double support phase, gait speed, step length, step width, and leg swing speed were analyzed. Results. Performance of cognitive tests during gait resulted in a statistically significant prolongation of the left (by 7% and right (by 7% foot gait cycle, shortening of the length of steps made with the right extremity (by 4%, reduction of speed of swings made with the left (by 11% and right (by 8% extremity, and reduction in gait speed (by 6%. Conclusions. Performance of cognitive tests during gait changes its individual pattern in relation to the level of the difficulty of the task.

Intention detection of gait initiation using EMG and kinematic data.

Science.gov (United States)

Wentink, E C; Beijen, S I; Hermens, H J; Rietman, J S; Veltink, P H

2013-02-01

Gait initiation in transfemoral amputees (TFA) is different from non-amputees. This is mainly caused by the lack of stability and push-off from the prosthetic leg. Adding control and artificial push-off to the prosthesis may therefore be beneficial to TFA. In this study the feasibility of real-time intention detection of gait initiation was determined by mimicking the TFA situation in non-amputees. EMG and inertial sensor data was measured in 10 non-amputees. Only data available in TFA was used to determine if gait initiation can be predicted in time to control a transfemoral prosthesis to generate push-off and stability. Toe-off and heel-strike of the leading limb are important parameters to be detected, to control a prosthesis and to time push-off. The results show that toe-off and heel-strike of the leading limb can be detected using EMG and kinematic data in non-amputees 130-260 ms in advance. This leaves enough time to control a prosthesis. Based on these results we hypothesize that similar results can be found in TFA, allowing for adequate control of a prosthesis during gait initiation. Copyright © 2012 Elsevier B.V. All rights reserved.

The influence of the Re-Link Trainer on gait symmetry in healthy adults.

Science.gov (United States)

Ward, Sarah; Wiedemann, Lukas; Stinear, Cathy; Stinear, James; McDaid, Andrew

2017-07-01

Walking function post-stroke is characterized by asymmetries in gait cycle parameters and joint kinematics. The Re-Link Trainer is designed to provide kinematic constraint to the paretic lower limb, to guide a physiologically normal and symmetrical gait pattern. The purpose of this pilot study was to assess the immediate influence of the Re-Link Trainer on measures of gait symmetry in healthy adults. Participants demonstrated a significantly lower cadence and a 62% reduction in walking speed in the Re-Link Trainer compared to normal walking. The step length ratio had a significant increase from 1.0 during normal walking to 2.5 when walking in the Re-Link Trainer. The results from this pilot study suggest in its current iteration the Re-Link Trainer imposes an asymmetrical constraint on lower limb kinematics.

Intra-rater repeatability of the Oxford foot model in healthy children in different stages of the foot roll over process during gait

DEFF Research Database (Denmark)

Curtis, D J; Bencke, J; Stebbins, J A

2009-01-01

BACKGROUND: The repeatability of the Oxford foot model has been reported, but possible variations in the repeatability during the foot roll over process have not been examined. The aim of this study was to determine the relative and absolute repeatability of the model for each stage of the foot...... roll over process during gait and to compare foot kinematic data from this study with that from another centre as a preliminary examination of the model's inter-centre repeatability and validity. METHOD: Eight healthy children were tested twice at the gait laboratory. Foot kinematics from this study...... were plotted against those from an earlier repeatability study and repeatability statistics calculated for the three rockers of stance phase and swing phase. RESULTS: Foot kinematics from this study and an earlier repeatability study produced similar kinematic patterns and joint angle ranges...

Aging effect on step adjustments and stability control in visually perturbed gait initiation.

Science.gov (United States)

Sun, Ruopeng; Cui, Chuyi; Shea, John B

2017-10-01

Gait adaptability is essential for fall avoidance during locomotion. It requires the ability to rapidly inhibit original motor planning, select and execute alternative motor commands, while also maintaining the stability of locomotion. This study investigated the aging effect on gait adaptability and dynamic stability control during a visually perturbed gait initiation task. A novel approach was used such that the anticipatory postural adjustment (APA) during gait initiation were used to trigger the unpredictable relocation of a foot-size stepping target. Participants (10 young adults and 10 older adults) completed visually perturbed gait initiation in three adjustment timing conditions (early, intermediate, late; all extracted from the stereotypical APA pattern) and two adjustment direction conditions (medial, lateral). Stepping accuracy, foot rotation at landing, and Margin of Dynamic Stability (MDS) were analyzed and compared across test conditions and groups using a linear mixed model. Stepping accuracy decreased as a function of adjustment timing as well as stepping direction, with older subjects exhibited a significantly greater undershoot in foot placement to late lateral stepping. Late adjustment also elicited a reaching-like movement (i.e. foot rotation prior to landing in order to step on the target), regardless of stepping direction. MDS measures in the medial-lateral and anterior-posterior direction revealed both young and older adults exhibited reduced stability in the adjustment step and subsequent steps. However, young adults returned to stable gait faster than older adults. These findings could be useful for future study of screening deficits in gait adaptability and preventing falls. Copyright © 2017 Elsevier B.V. All rights reserved.

The effects of gait retraining in runners with patellofemoral pain: A randomized trial.

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Roper, Jenevieve L; Harding, Elizabeth M; Doerfler, Deborah; Dexter, James G; Kravitz, Len; Dufek, Janet S; Mermier, Christine M

2016-06-01

Running popularity has increased resulting in a concomitant increase in running-related injuries with patellofemoral pain most commonly reported. The purpose of this study was to determine whether gait retraining by modifying footstrike patterns from rearfoot strike to forefoot strike reduces patellofemoral pain and improves associated biomechanical measures, and whether the modification influences risk of ankle injuries. Sixteen subjects (n=16) were randomly placed in the control (n=8) or experimental (n=8) group. The experimental group performed eight gait retraining running sessions over two weeks where footstrike pattern was switched from rearfoot strike to forefoot strike, while the control group performed running sessions with no intervention. Variables were recorded pre-, post-, and one-month post-running trials. Knee pain was significantly reduced post-retraining (Pforefoot strike pattern leads to reduced knee pain, and should be considered a possible strategy for management of patellofemoral pain in recreational runners. This trial is registered at the US National Institutes of Health (clinicaltrials.gov) #NCT02567123. Published by Elsevier Ltd.

Moving from laboratory to real life conditions: Influence on the assessment of variability and stability of gait.

Science.gov (United States)

Tamburini, Paola; Storm, Fabio; Buckley, Chris; Bisi, Maria Cristina; Stagni, Rita; Mazzà, Claudia

2018-01-01

The availability of wearable sensors allows shifting gait analysis from the traditional laboratory settings, to daily life conditions. However, limited knowledge is available about whether alterations associated to different testing environment (e.g. indoor or outdoor) and walking protocols (e.g. free or controlled), result from actual differences in the motor behaviour of the tested subjects or from the sensitivity to these changes of the indexes adopted for the assessment. In this context, it was hypothesized that testing environment and walking protocols would not modify motor control stability in the gait of young healthy adults, who have a mature and structured gait pattern, but rather the variability of their motor pattern. To test this hypothesis, data from trunk and shank inertial sensors were collected from 19 young healthy participants during four walking tasks in different environments (indoor and outdoor) and in both controlled (i.e. following a predefined straight path) and free conditions. Results confirmed what hypothesized: variability indexes (Standard deviation, Coefficient of variation and Poincaré plots) were significantly influenced by both environment and walking conditions. Stability indexes (Harmonic ratio, Short term Lyapunov exponents, Recurrence quantification analysis and Sample entropy), on the contrary, did not highlight any change in the motor control. In conclusion, this study highlighted an influence of environment and testing condition on the assessment of specific characteristics of gait (i.e. variability and stability). In particular, for young healthy adults, both environment and testing conditions affect gait variability indexes, whereas neither affect gait stability indexes. Copyright © 2017. Published by Elsevier B.V.

Pre- and post-operative gait analysis for evaluation of neck pain in chronic whiplash

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Ginsburg Glen M

2009-07-01

Full Text Available Abstract Introduction Chronic neck pain after whiplash is notoriously refractory to conservative treatment, and positive radiological findings to explain the symptoms are scarce. The apparent disproportionality between subjective complaints and objective findings is significant for the planning of treatment, impairment ratings, and judicial questions on causation. However, failure to identify a symptom's focal origin with routine imaging studies does not invalidate the symptom per se. It is therefore of a general interest both to develop effective therapeutic strategies in chronic whiplash, and to establish techniques for objectively evaluation of treatment outcomes. Methods Twelve patients with chronic neck pain after whiplash underwent pre- and postoperative computerized 3D gait analysis. Results Significant improvement was found in all gait parameters, cervical range-of-motion, and self reported pain (VAS. Conclusion Chronic neck pain is associated with abnormal cervical spine motion and gait patterns. 3D gait analysis is a useful instrument to assess the outcome of treatment for neck pain.

Effects of sex and obesity on gait biomechanics before and six months after total knee arthroplasty: A longitudinal cohort study.

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Paterson, K L; Sosdian, L; Hinman, R S; Wrigley, T V; Kasza, J; Dowsey, M; Choong, P; Bennell, K L

2018-03-01

Gait biomechanics, sex, and obesity can contribute to suboptimal outcomes from primary total knee arthroplasty. The aims of this study were to i) determine if sex and/or obesity influence the amount of change in gait biomechanics from pre-surgery to six months post-surgery and; ii) assess if gait returns to normal in men and women. Three-dimensional gait analysis was performed on 43 patients undergoing primary total knee arthroplasty for knee osteoarthritis (pre- and six months post-operative) and 40 asymptomatic controls. Mixed linear regression models were fit to assess which factors influenced change in gait biomechanics within the arthroplasty cohort, and interaction terms were included to assess if biomechanics returned to normal following surgery. Male peak knee adduction moment (p biomechanics after arthroplasty. Men retained abnormal gait patterns after surgery, whilst women did not. Further research should determine the long-term implications of gait abnormalities seen in men after arthroplasty. Copyright © 2018 Elsevier B.V. All rights reserved.

Effects of conventional overground gait training and a gait trainer with partial body weight support on spatiotemporal gait parameters of patients after stroke

OpenAIRE

Park, Byoung-Sun; Kim, Mee-Young; Lee, Lim-Kyu; Yang, Seung-Min; Lee, Won-Deok; Noh, Ji-Woong; Shin, Yong-Sub; Kim, Ju-Hyun; Lee, Jeong-Uk; Kwak, Taek-Yong; Lee, Tae-Hyun; Kim, Ju-Young; Kim, Junghwan

2015-01-01

[Purpose] The purpose of this study was to confirm the effects of both conventional overground gait training (CGT) and a gait trainer with partial body weight support (GTBWS) on spatiotemporal gait parameters of patients with hemiparesis following chronic stroke. [Subjects and Methods] Thirty stroke patients were alternately assigned to one of two treatment groups, and both groups underwent CGT and GTBWS. [Results] The functional ambulation classification on the affected side improved signifi...

Self-perceived gait stability modulates the effect of daily life gait quality on prospective falls in older adults.

Science.gov (United States)

Weijer, R H A; Hoozemans, M J M; van Dieën, J H; Pijnappels, M

2018-05-01

Quality of gait during daily life activities and perceived gait stability are both independent risk factors for future falls in older adults. We investigated whether perceived gait stability modulates the association between gait quality and falling in older adults. In this prospective cohort study, we used one-week daily-life trunk acceleration data of 272 adults over 65 years of age. Sample entropy (SE) of the 3D acceleration signals was calculated to quantify daily life gait quality. To quantify perceived gait stability, the level of concern about falling was assessed using the Falls Efficacy Scale international (FES-I) questionnaire and step length, estimated from the accelerometer data. A fall calendar was used to record fall incidence during a six-month follow up period. Logistic regression analyses were performed to study the association between falling and SE, step length or FES-I score, and their interactions. High (i.e., poor) SE in vertical direction was significantly associated with falling. FES-I scores significantly modulated this association, whereas step length did not. Subgroup analyses based on FES-I scores showed that high SE in the vertical direction was a risk factor for falls only in older adults who had a high (i.e. poor) FES-I score. In conclusion, perceived gait stability modulates the association between gait quality and falls in older adults such that an association between gait quality and falling is only present when perceived gait stability is poor. The results of the present study indicate that the effectiveness of interventions for fall prevention, aimed at improving gait quality, may be affected by a modulating effect of perceived gait stability. Results indicate that interventions to reduce falls in older adults might sort most effectiveness in populations with both a poor physiological and psychological status. Copyright © 2018 Elsevier B.V. All rights reserved.

Comparing the Effect of Balance Training with and Without Suit Therapy on the Balance and the Gait Pattern of Patients with Parkinsin\\'s Disease

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Majid Khodadadi

2016-09-01

Full Text Available Background & Objective: Parkinson's Disease  is a progressive neurologic disorder affecting the central nervous system. The objective of this study is to investigate the effect of balance training with and without suit therapy on the balance and the gait pattern of patients with Parkinson's Disease. Material & Methods: participants with Parkinson's Disease were divided  into three groups of control, with suit therapy, and without suit therapy. The control group received only pharmacotherapy, while the groups with and without suit therapy received eigh weeks balance training in addition to pharmacotherapy. The patient's balance  and gait  were evaluted by Berg and Tinetti scales, respectively at the pretest and posttest of this study. Result: The result of the study showed significant difference in balance between the three groups (P<0/05. The groups with and without suit therapy were significantly more effective than control group (P<0/05, but between groups with and without suit therapy no significant difference was observed (P=0/076. The result of the study also revealed significant difference in gait between the three groups (P<0/05. The groups with and without suit therapy were significantly more effective than control group (P<0/05, and the group with suit therapy was significantly more effective than the group without suit therapy (P<0/05. Conclusion: To do balance traning is better than not to do it, and balance training with suit therapy is better than without suit therapy

Quantitative Gait Measurement With Pulse-Doppler Radar for Passive In-Home Gait Assessment

OpenAIRE

Wang, Fang; Skubic, Marjorie; Rantz, Marilyn; Cuddihy, Paul E.

2014-01-01

In this paper, we propose a pulse-Doppler radar system for in-home gait assessment of older adults. A methodology has been developed to extract gait parameters including walking speed and step time using Doppler radar. The gait parameters have been validated with a Vicon motion capture system in the lab with 13 participants and 158 test runs. The study revealed that for an optimal step recognition and walking speed estimation, a dual radar set up with one radar placed at foot level and the ot...

Gait, mobility, and falls in older people

OpenAIRE

Gschwind, Yves Josef

2012-01-01

My doctoral thesis contributes to the understanding of gait, mobility, and falls in older people. All presented projects investigated the most prominent and sensitive markers for fall-related gait changes, that is gait velocity and gait variability. Based on the measurement of these spatio-temporal gait parameters, particularly when using a change-sensitive dual task paradigm, it is possible to make conclusions regarding walking, balance, activities of daily living, and falls in o...

Development of a three-dimensional dynamic biped walking via the oscillation of telescopic knee joint and its gait analysis

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T. Kinugasa

2015-12-01

Full Text Available The purpose of this study is to extend the three-dimensional (3-D passive dynamic biped walker to a 3-D dynamic biped walker, i.e., a walker that can walk on a horizontal surface based on a passive dynamic walking. A new prototype of 3-D biped walker called RW04, which has telescopic knee joints, was developed and its ability for walking was validated through some experiments. A sinusoidal oscillation, which is regarded as a central pattern generator with no sensory feedback, was provided to the knee joints to achieve the biped walking. The results showed that the biped gait of RW04 was possible only via a sinusoidal oscillation of the knee joint. Moreover, the 3-D dynamic walking gait via frequency response and zero moment point (ZMP trajectory was also analyzed. The biped locomotion had a resonance, i.e., the frequency matched the natural frequency of the locomotion in the gain property. An “8” shaped ZMP trajectory was observed, which was found to be similar to that of the human gait. However, the simple sinusoidal oscillation had limitations such as stride reduction or discontinuation by phase difference. Therefore, in future work, more adaptable control strategy such as a sensory feedback using ZMP should be provided.

Does patella lowering improve crouch gait in cerebral palsy? Comparative retrospective study.

Science.gov (United States)

Desailly, E; Thévenin-Lemoine, C; Khouri, N

2017-09-01

Patella lowering aims to improve quadriceps function as a means of correcting crouch gait in patients with cerebral palsy. Few studies have assessed the effects of patella lowering as a component of multilevel surgery. Including patella lowering into the components of multilevel surgery is beneficial in patients with crouch gait and patella alta. In 12 lower limbs with patella alta (Caton-Deschamps index>1.4) in 41 children with cerebral palsy, patella lowering was performed, without distal femoral extension osteotomy or hamstring release. Among limbs with similar surgical procedures (e.g., hamstring lengthening, rectus femoris transfer) except for patella lowering, controls were selected retrospectively by matching on a propensity score for patella lowering. The propensity score was computed based on preoperative knee flexion contracture, knee extension lag, and minimum knee flexion at mid-stance. Clinical and 3D kinematic data were compared between the two groups. The improvement in minimum knee flexion at mid-stance was significantly greater in the group with patellar lowering (-24°±12°vs. -12°±7°). The Gait Deviation Index improved similarly in the two groups. Knee flexion contracture improved only in the group with patellar lowering. Extension lag did not improve in either group. Peak knee flexion during the swing phase remained unchanged in both groups. Patellar lowering is effective in diminishing minimum knee flexion at mid-stance in patients with patella alta and crouch gait due to cerebral palsy. Patellar lowering has not adverse effects on gait. These findings cannot be assumed to apply to patients with normal patellar height. IV (retrospective study). Copyright © 2017. Published by Elsevier Masson SAS.

Physiotherapy, based on the Bobath concept, may influence the gait pattern in persons with limb-girdle muscle dystrophy: a multiple case series study.

Science.gov (United States)

Oygard, Kjellaug; Haestad, Helge; Jørgensen, Lone

2011-03-01

 There are few studies on possible effects of physiotherapy for adults with muscular dystrophy. The aim of this study was to examine if treatment based on the Bobath concept may influence specific gait parameters in some of these patients.   A single-subject experimental design with A-B-A-A phases was used, and four patients, three with limb-girdle muscular dystrophy (LGMD) and one with fascioscapulohumeral muscular dystrophy (FSHD), were included. The patients had 1 hour of individually tailored physiotherapy at each working day for a period of 3 weeks. Step length, step width and gait velocity were measured during the A-B-A-A phases by use of an electronic walkway. Walking distance and endurance were measured by use of the '6 minute walk test'.  . The three LGMD patients, who initially walked with a wide base of support, had a narrower, velocity-adjusted step width after treatment, accompanied with the same or even longer step length. These changes lasted throughout follow-up. Moreover, two of the patients were able to walk a longer distance within 6 minutes after the treatment period. The fourth patient (with FSHD) had a normal step width at baseline, which did not change during the study.   The results indicate that physiotherapy treatment based on the Bobath concept may influence the gait pattern in patients with LGMD. However, in order to evaluate the effectiveness of physiotherapy to patients with muscular dystrophies, we call for larger studies and controlled trials. Copyright © 2010 John Wiley & Sons, Ltd.

Advanced Prosthetic Gait Training Tool

Science.gov (United States)

2015-12-01

modules to train individuals to distinguish gait deviations (trunk motion and lower-limb motion). Each of these modules help trainers improve their...AWARD NUMBER: W81XWH-10-1-0870 TITLE: Advanced Prosthetic Gait Training Tool PRINCIPAL INVESTIGATOR: Dr. Karim Abdel-Malek CONTRACTING...study is to produce a computer-based Advanced Prosthetic Gait Training Tool to aid in the training of clinicians at military treatment facilities

LSTM for diagnosis of neurodegenerative diseases using gait data

Science.gov (United States)

Zhao, Aite; Qi, Lin; Li, Jie; Dong, Junyu; Yu, Hui

2018-04-01

Neurodegenerative diseases (NDs) usually cause gait disorders and postural disorders, which provides an important basis for NDs diagnosis. By observing and analyzing these clinical manifestations, medical specialists finally give diagnostic results to the patient, which is inefficient and can be easily affected by doctors' subjectivity. In this paper, we propose a two-layer Long Short-Term Memory (LSTM) model to learn the gait patterns exhibited in the three NDs. The model was trained and tested using temporal data that was recorded by force-sensitive resistors including time series, such as stride interval and swing interval. Our proposed method outperforms other methods in literature in accordance with accuracy of the predicted diagnostic result. Our approach aims at providing the quantitative assessment so that to indicate the diagnosis and treatment of these neurodegenerative diseases in clinic

Is gait variability reliable in older adults and Parkinson's disease? Towards an optimal testing protocol.

Science.gov (United States)

Galna, Brook; Lord, Sue; Rochester, Lynn

2013-04-01

Despite the widespread use of gait variability in research and clinical studies, testing protocols designed to optimise its reliability have not been established. This study evaluates the impact of testing protocol and pathology on the reliability of gait variability. To (i) estimate the reliability of gait variability during continuous and intermittent walking protocols in older adults and people with Parkinson's disease (PD), (ii) determine optimal number of steps for acceptable levels of reliability of gait variability and (iii) provide sample size estimates for use in clinical trials. Gait variability was measured twice, one week apart, in 27 older adults and 25 PD participants. Participants walked at their preferred pace during: (i) a continuous 2 min walk and (ii) 3 intermittent walks over a 12 m walkway. Gait variability was calculated as the within-person standard deviation for step velocity, length and width, and step, stance and swing duration. Reliability of gait variability ranged from poor to excellent (intra class correlations .041-.860; relative limits of agreement 34-89%). Gait variability was more reliable during continuous walks. Control and PD participants demonstrated similar reliability. Increasing the number of steps improved reliability, with most improvement seen across the first 30 steps. In this study, we identified testing protocols that improve the reliability of measuring gait variability. We recommend using a continuous walking protocol and to collect no fewer than 30 steps. Early PD does not appear to impact negatively on the reliability of gait variability. Copyright © 2012 Elsevier B.V. All rights reserved.

A musculoskeletal foot model for clinical gait analysis.

Science.gov (United States)

Saraswat, Prabhav; Andersen, Michael S; Macwilliams, Bruce A

2010-06-18

Several full body musculoskeletal models have been developed for research applications and these models may potentially be developed into useful clinical tools to assess gait pathologies. Existing full-body musculoskeletal models treat the foot as a single segment and ignore the motions of the intrinsic joints of the foot. This assumption limits the use of such models in clinical cases with significant foot deformities. Therefore, a three-segment musculoskeletal model of the foot was developed to match the segmentation of a recently developed multi-segment kinematic foot model. All the muscles and ligaments of the foot spanning the modeled joints were included. Muscle pathways were adjusted with an optimization routine to minimize the difference between the muscle flexion-extension moment arms from the model and moment arms reported in literature. The model was driven by walking data from five normal pediatric subjects (aged 10.6+/-1.57 years) and muscle forces and activation levels required to produce joint motions were calculated using an inverse dynamic analysis approach. Due to the close proximity of markers on the foot, small marker placement error during motion data collection may lead to significant differences in musculoskeletal model outcomes. Therefore, an optimization routine was developed to enforce joint constraints, optimally scale each segment length and adjust marker positions. To evaluate the model outcomes, the muscle activation patterns during walking were compared with electromyography (EMG) activation patterns reported in the literature. Model-generated muscle activation patterns were observed to be similar to the EMG activation patterns. Published by Elsevier Ltd.

Control Architecture of a 10 DOF Lower Limbs Exoskeleton for Gait Rehabilitation

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Natasa Koceska

2013-01-01

Full Text Available This paper describes the control architecture of a 10 DOF (Degrees of Freedom lower limbs exoskeleton for the gait rehabilitation of patients with gait dysfunction. The system has 4 double-acting rod pneumatic actuators (two for each leg that control the hip and knee joints. The motion of each cylinder's piston is controlled by two proportional pressure valves, connected to both cylinder chambers. The control strategy has been specifically designed in order to ensure a proper trajectory control for guiding patient's legs along a fixed reference gait pattern. An adaptive fuzzy controller which is capable of compensating for the influence of the dry friction was successfully designed, implemented and tested on an embedded real-time PC/104. In order to verify the proposed control architecture, laboratory experiments without a patient were carried out and the results are reported here and discussed.

Speed-Dependent Modulation of the Locomotor Behavior in Adult Mice Reveals Attractor and Transitional Gaits.

Science.gov (United States)

Lemieux, Maxime; Josset, Nicolas; Roussel, Marie; Couraud, Sébastien; Bretzner, Frédéric

2016-01-01

Locomotion results from an interplay between biomechanical constraints of the muscles attached to the skeleton and the neuronal circuits controlling and coordinating muscle activities. Quadrupeds exhibit a wide range of locomotor gaits. Given our advances in the genetic identification of spinal and supraspinal circuits important to locomotion in the mouse, it is now important to get a better understanding of the full repertoire of gaits in the freely walking mouse. To assess this range, young adult C57BL/6J mice were trained to walk and run on a treadmill at different locomotor speeds. Instead of using the classical paradigm defining gaits according to their footfall pattern, we combined the inter-limb coupling and the duty cycle of the stance phase, thus identifying several types of gaits: lateral walk, trot, out-of-phase walk, rotary gallop, transverse gallop, hop, half-bound, and full-bound. Out-of-phase walk, trot, and full-bound were robust and appeared to function as attractor gaits (i.e., a state to which the network flows and stabilizes) at low, intermediate, and high speeds respectively. In contrast, lateral walk, hop, transverse gallop, rotary gallop, and half-bound were more transient and therefore considered transitional gaits (i.e., a labile state of the network from which it flows to the attractor state). Surprisingly, lateral walk was less frequently observed. Using graph analysis, we demonstrated that transitions between gaits were predictable, not random. In summary, the wild-type mouse exhibits a wider repertoire of locomotor gaits than expected. Future locomotor studies should benefit from this paradigm in assessing transgenic mice or wild-type mice with neurotraumatic injury or neurodegenerative disease affecting gait.

Anticipatory postural adjustment patterns during gait initiation across the adult lifespan.

Science.gov (United States)

Lu, Chiahao; Amundsen Huffmaster, Sommer L; Harvey, Jack C; MacKinnon, Colum D

2017-09-01

Gait initiation involves a complex sequence of anticipatory postural adjustments (APAs) during the transition from steady state standing to forward locomotion. APAs have four core components that function to accelerate the center of mass forwards and towards the initial single-support stance limb. These components include loading of the initial step leg, unloading of the initial stance leg, and excursion of the center of pressure in the posterior and lateral (towards the stepping leg) directions. This study examined the incidence, magnitude, and timing of these components and how they change across the lifespan (ages 20-79). 157 individuals performed five trials of self-paced, non-cued gait initiation on an instrumented walkway. At least one component of the APA was absent in 24% of all trials. The component most commonly absent was loading of the initial step leg (absent in 10% of all trials in isolation, absent in 10% of trials in conjunction with another missing component). Trials missing all four components were rare (1%) and were observed in both younger and older adults. There was no significant difference across decades in the incidence of trials without an APA, the number or type of APA components absent, or the magnitude or timing of the APA components. These data demonstrate that one or more components of the APA sequence are commonly absent in the general population and the spatiotemporal profile of the APA does not markedly change with ageing. Copyright © 2017 Elsevier B.V. All rights reserved.

Development of a novel virtual reality gait intervention.

Science.gov (United States)

Boone, Anna E; Foreman, Matthew H; Engsberg, Jack R

2017-02-01

Improving gait speed and kinematics can be a time consuming and tiresome process. We hypothesize that incorporating virtual reality videogame play into variable improvement goals will improve levels of enjoyment and motivation and lead to improved gait performance. To develop a feasible, engaging, VR gait intervention for improving gait variables. Completing this investigation involved four steps: 1) identify gait variables that could be manipulated to improve gait speed and kinematics using the Microsoft Kinect and free software, 2) identify free internet videogames that could successfully manipulate the chosen gait variables, 3) experimentally evaluate the ability of the videogames and software to manipulate the gait variables, and 4) evaluate the enjoyment and motivation from a small sample of persons without disability. The Kinect sensor was able to detect stride length, cadence, and joint angles. FAAST software was able to identify predetermined gait variable thresholds and use the thresholds to play free online videogames. Videogames that involved continuous pressing of a keyboard key were found to be most appropriate for manipulating the gait variables. Five participants without disability evaluated the effectiveness for modifying the gait variables and enjoyment and motivation during play. Participants were able to modify gait variables to permit successful videogame play. Motivation and enjoyment were high. A clinically feasible and engaging virtual intervention for improving gait speed and kinematics has been developed and initially tested. It may provide an engaging avenue for achieving thousands of repetitions necessary for neural plastic changes and improved gait. Copyright © 2016 Elsevier B.V. All rights reserved.

Scaling of avian bipedal locomotion reveals independent effects of body mass and leg posture on gait.

Science.gov (United States)

Daley, Monica A; Birn-Jeffery, Aleksandra

2018-05-22

Birds provide an interesting opportunity to study the relationships between body size, limb morphology and bipedal locomotor function. Birds are ecologically diverse and span a large range of body size and limb proportions, yet all use their hindlimbs for bipedal terrestrial locomotion, for at least some part of their life history. Here, we review the scaling of avian striding bipedal gaits to explore how body mass and leg morphology influence walking and running. We collate literature data from 21 species, spanning a 2500× range in body mass from painted quail to ostriches. Using dynamic similarity theory to interpret scaling trends, we find evidence for independent effects of body mass, leg length and leg posture on gait. We find no evidence for scaling of duty factor with body size, suggesting that vertical forces scale with dynamic similarity. However, at dynamically similar speeds, large birds use relatively shorter stride lengths and higher stride frequencies compared with small birds. We also find that birds with long legs for their mass, such as the white stork and red-legged seriema, use longer strides and lower swing frequencies, consistent with the influence of high limb inertia on gait. We discuss the observed scaling of avian bipedal gait in relation to mechanical demands for force, work and power relative to muscle actuator capacity, muscle activation costs related to leg cycling frequency, and considerations of stability and agility. Many opportunities remain for future work to investigate how morphology influences gait dynamics among birds specialized for different habitats and locomotor behaviors. © 2018. Published by The Company of Biologists Ltd.

Modeling and simulation of normal and hemiparetic gait

Science.gov (United States)

Luengas, Lely A.; Camargo, Esperanza; Sanchez, Giovanni

2015-09-01

Gait is the collective term for the two types of bipedal locomotion, walking and running. This paper is focused on walking. The analysis of human gait is of interest to many different disciplines, including biomechanics, human-movement science, rehabilitation and medicine in general. Here we present a new model that is capable of reproducing the properties of walking, normal and pathological. The aim of this paper is to establish the biomechanical principles that underlie human walking by using Lagrange method. The constraint forces of Rayleigh dissipation function, through which to consider the effect on the tissues in the gait, are included. Depending on the value of the factor present in the Rayleigh dissipation function, both normal and pathological gait can be simulated. First of all, we apply it in the normal gait and then in the permanent hemiparetic gait. Anthropometric data of adult person are used by simulation, and it is possible to use anthropometric data for children but is necessary to consider existing table of anthropometric data. Validation of these models includes simulations of passive dynamic gait that walk on level ground. The dynamic walking approach provides a new perspective of gait analysis, focusing on the kinematics and kinetics of gait. There have been studies and simulations to show normal human gait, but few of them have focused on abnormal, especially hemiparetic gait. Quantitative comparisons of the model predictions with gait measurements show that the model can reproduce the significant characteristics of normal gait.

Gait Partitioning Methods: A Systematic Review

Directory of Open Access Journals (Sweden)

Juri Taborri

2016-01-01

Full Text Available In the last years, gait phase partitioning has come to be a challenging research topic due to its impact on several applications related to gait technologies. A variety of sensors can be used to feed algorithms for gait phase partitioning, mainly classifiable as wearable or non-wearable. Among wearable sensors, footswitches or foot pressure insoles are generally considered as the gold standard; however, to overcome some inherent limitations of the former, inertial measurement units have become popular in recent decades. Valuable results have been achieved also though electromyography, electroneurography, and ultrasonic sensors. Non-wearable sensors, such as opto-electronic systems along with force platforms, remain the most accurate system to perform gait analysis in an indoor environment. In the present paper we identify, select, and categorize the available methodologies for gait phase detection, analyzing advantages and disadvantages of each solution. Finally, we comparatively examine the obtainable gait phase granularities, the usable computational methodologies and the optimal sensor placements on the targeted body segments.

Gait Partitioning Methods: A Systematic Review

Science.gov (United States)

Taborri, Juri; Palermo, Eduardo; Rossi, Stefano; Cappa, Paolo

2016-01-01

In the last years, gait phase partitioning has come to be a challenging research topic due to its impact on several applications related to gait technologies. A variety of sensors can be used to feed algorithms for gait phase partitioning, mainly classifiable as wearable or non-wearable. Among wearable sensors, footswitches or foot pressure insoles are generally considered as the gold standard; however, to overcome some inherent limitations of the former, inertial measurement units have become popular in recent decades. Valuable results have been achieved also though electromyography, electroneurography, and ultrasonic sensors. Non-wearable sensors, such as opto-electronic systems along with force platforms, remain the most accurate system to perform gait analysis in an indoor environment. In the present paper we identify, select, and categorize the available methodologies for gait phase detection, analyzing advantages and disadvantages of each solution. Finally, we comparatively examine the obtainable gait phase granularities, the usable computational methodologies and the optimal sensor placements on the targeted body segments. PMID:26751449

FY1995 study of feedback type gait training system; 1995 nendo feedback gata hoko kuren sochi ni kansuru kenkyu kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

The purpose of this project is to develop and demonstrate the utility of feedback type gait training equipment designed for the measurement and evaluation by a walking training of the aged or patient. As similar concepts of walking training, a locomotion in the water for the aged is applied in rehabilitation. Our development of this study established the system of a suspending mechanism which revolves around the prop, and a walking on the circular type force plate by the aged or patient. It is possible to detect a walking reaction force of several patients from force plate simultaneously. And then, the data from force plate makes feedback signal to put up the patient like a buoyancy in the water. Concerning the evaluations of walking pattern a step range, a hanging ratio and a walking speed, etc. are acquired for each patient by the acknowledgment base. This system is actively able to perform a walking training continuously compared with conventional passive gait equipment. (NEDO)

Simple analytical model reveals the functional role of embodied sensorimotor interaction in hexapod gaits

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Aoi, Shinya; Nachstedt, Timo; Manoonpong, Poramate; Wörgötter, Florentin; Matsuno, Fumitoshi

2018-01-01

Insects have various gaits with specific characteristics and can change their gaits smoothly in accordance with their speed. These gaits emerge from the embodied sensorimotor interactions that occur between the insect’s neural control and body dynamic systems through sensory feedback. Sensory feedback plays a critical role in coordinated movements such as locomotion, particularly in stick insects. While many previously developed insect models can generate different insect gaits, the functional role of embodied sensorimotor interactions in the interlimb coordination of insects remains unclear because of their complexity. In this study, we propose a simple physical model that is amenable to mathematical analysis to explain the functional role of these interactions clearly. We focus on a foot contact sensory feedback called phase resetting, which regulates leg retraction timing based on touchdown information. First, we used a hexapod robot to determine whether the distributed decoupled oscillators used for legs with the sensory feedback generate insect-like gaits through embodied sensorimotor interactions. The robot generated two different gaits and one had similar characteristics to insect gaits. Next, we proposed the simple model as a minimal model that allowed us to analyze and explain the gait mechanism through the embodied sensorimotor interactions. The simple model consists of a rigid body with massless springs acting as legs, where the legs are controlled using oscillator phases with phase resetting, and the governed equations are reduced such that they can be explained using only the oscillator phases with some approximations. This simplicity leads to analytical solutions for the hexapod gaits via perturbation analysis, despite the complexity of the embodied sensorimotor interactions. This is the first study to provide an analytical model for insect gaits under these interaction conditions. Our results clarified how this specific foot contact sensory

Unstable gait due to spasticity of the rectus femoris: gait analysis and motor nerve block.

Science.gov (United States)

Gross, R; Leboeuf, F; Rémy-Néris, O; Perrouin-Verbe, B

2012-12-01

We present the case of a 54 year-old man presenting with a right Brown-Séquard plus syndrome (BSPS) after a traumatic cervical spinal cord injury. After being operated on with selective tibial neurotomy and triceps surae lengthening because of a right spastic equinus foot, he developed a gait disorder at high speed. The patient complained about an instability of the right knee. Observational gait analysis exhibited an oscillating, flexion/extension motion of the right knee during stance, which was confirmed by gait analysis. Dynamic electromyographic recordings exhibited a clonus of the right rectus femoris (RF) during stance. The spastic activity of the RF and the abnormal knee motion totally reversed after a motor nerve block of the RF, as well as after botulinum toxin type A injection into the RF. We emphasize that complex, spastic gait disorders can benefit from a comprehensive assessment including gait analysis and nerve blocks. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Asymmetry of Anticipatory Postural Adjustment During Gait Initiation

Directory of Open Access Journals (Sweden)

Hiraoka Koichi

2014-10-01

Full Text Available The purpose of this study was to investigate the asymmetry of anticipatory postural adjustment (APA during gait initiation and to determine whether the process of choosing the initial swing leg affects APA during gait initiation. The participants initiated gait with the leg indicated by a start tone or initiated gait with the leg spontaneously chosen. The dependent variables of APA were not significantly different among the condition of initiating gait with the preferred leg indicated by the start tone, the condition of initiating gait with the non-preferred leg indicated by the start tone, and the condition of initiating gait with the leg spontaneously chosen. These findings fail to support the view that the process of choosing the initial swing leg affects APA during gait initiation. The lateral displacement of the center of pressure in the period in which shifting the center of pressure to the initial swing phase before initiating gait with the left leg indicated by the external cue was significantly larger than that when initiating gait with the right leg indicated by the external cue, and significantly larger than that when initiating gait with the leg spontaneously chosen. Weight shift to the initial swing side during APA during gait initiation was found to be asymmetrical when choosing the leg in response to an external cue

Tic-induced gait dysfunction.

NARCIS (Netherlands)

Fasano, A.; Ruzicka, E.; Bloem, B.R.

2012-01-01

BACKGROUND: Many neurological disorders impair gait, but only a few of them are episodic or paroxysmal, the most important ones being freezing of gait and paroxysmal dyskinesias. METHODS: We describe 4 patients with tic disorders (3 with Tourette syndrome, and 1 with a tic disorder secondary to

How doing a dynamical analysis of gait movement may provide information about Autism

Science.gov (United States)

Wu, D.; Torres, E.; Nguyen, J.; Mistry, S.; Whyatt, C.; Kalampratsidou, V.; Kolevzon, A.; Jose, J.

Individuals with Autism Spectrum Disorder (ASD) are known to have deficits in language and social skills. They also have deficits on how they move. Why individuals get ASD? It is not generally known. There is, however, one particular group of children with a SHANK3 gene deficiency (Phelan-McDermid Syndrome (PMDS)) that present symptoms similar to ASD. We have been searching for universal mechanism in ASD going beyond the usual heterogeneous ASD symptoms. We studied motions in gaits for both PMDS patients and idiopathic ASD. We have examined their motions continuously at milliseconds time scale, away from naked eye detection. Gait is a complex process, requiring a complex integration and coordination of different joints' motions. Significant information about the development and/or deficits in the sensory system is hidden in our gaits. We discovered that the speed smoothness in feet motion during gaits is a critical feature that provides a significant distinction between subjects with ASD and typical controls. The differences in appearance of the speed fluctuations suggested a different coordination mechanism in subjects with disorders. Our work provides a very important feature in gait motion that has significant physiological information.

Dalfampridine in Parkinson's disease related gait dysfunction: A randomized double blind trial.

Science.gov (United States)

Luca, Corneliu C; Nadayil, Gloria; Dong, Chuanhui; Nahab, Fatta B; Field-Fote, Edelle; Singer, Carlos

2017-08-15

Disease-related gait dysfunction causes extensive disability for persons with Parkinson's disease (PD), with no effective therapies currently available. The potassium channel blocker dalfampridine has been used in multiple neurological conditions and improves walking in persons with multiple sclerosis. We aimed to evaluate the effect of dalfampridine extended release (D-ER) 10mg tablets twice daily on different domains of walking in participants with PD. Twenty-two participants with PD and gait dysfunction were randomized to receive D-ER 10mg twice daily or placebo for 4weeks in a crossover design with a 2-week washout period. The primary outcomes were change in the gait velocity and stride length. At 4weeks, gait velocity was not significantly different between D-ER (0.89m/s±0.33) and placebo (0.93m/s±0.27) conditions. The stride length was also similar between conditions: 0.96m±0.38 for D-ER versus 1.06m±0.33 for placebo. D-ER was generally well tolerated with the most frequent side effects being dizziness, nausea and balance problems. D-ER is well tolerated in PD patients, however it did not show significant benefit for gait impairment. Copyright © 2017 Elsevier B.V. All rights reserved.

LOPES: Selective control of gait functions during the gait rehabilitation of CVA patients

NARCIS (Netherlands)

Ekkelenkamp, R.; Veneman, J.F.; van der Kooij, Herman

2005-01-01

LOPES aims for an active role of the patient by selective and partial support of gait functions during robotic treadmill training sessions. Virtual model control (VMC) was applied to the robot as an intuitive method for translating current treadmill gait rehabilitation therapy programs into robotic

Effects of unilateral real-time biofeedback on propulsive forces during gait.

Science.gov (United States)

Schenck, Christopher; Kesar, Trisha M

2017-06-06

In individuals with post-stroke hemiparesis, reduced push-off force generation in the paretic leg negatively impacts walking function. Gait training interventions that increase paretic push-off can improve walking function in individuals with neurologic impairment. During normal locomotion, push-off forces are modulated with variations in gait speed and slope. However, it is unknown whether able-bodied individuals can selectively modulate push-off forces from one leg in response to biofeedback. Here, in a group of young, neurologically-unimpaired individuals, we determined the effects of a real-time visual and auditory biofeedback gait training paradigm aimed at unilaterally increasing anteriorly-directed ground reaction force (AGRF) in the targeted leg. Ground reaction force data during were collected from 7 able-bodied individuals as they walked at a self-selected pace on a dual-belt treadmill instrumented with force platforms. During 11-min of gait training, study participants were provided real-time AGRF biofeedback encouraging a 20-30% increase in peak AGRF generated by their right (targeted) leg compared to their baseline (pre-training) AGRF. AGRF data were collected before, during, and after the biofeedback training period, as well as during two retention tests performed without biofeedback and after standing breaks. Compared to AGRFs generated during the pre-training gait trials, participants demonstrated a significantly greater AGRF in the targeted leg during and immediately after training, indicating that biofeedback training was successful at inducing increased AGRF production in the targeted leg. Additionally, participants continued to demonstrate greater AGRF production in the targeted leg after two standing breaks, showing short-term recall of the gait pattern learned during the biofeedback training. No significant effects of training were observed on the AGRF in the non-targeted limb, showing the specificity of the effects of biofeedback toward the

1 Spatial asymmetry of post-stroke hemiparetic gait: assessment and ...

African Journals Online (AJOL)

of this study was to evaluate the potential of the footprint and Symmetry Index ... asymmetry increase risk of falls and related injuries of patients (Weerdesteyn et al., 2008). ... This limits the opportunities for the assessment of gait pattern in many hospitals and ... duration post-stroke period of at least 6 months; (ii) ability to walk ...

Gait recognition based on integral outline

Science.gov (United States)

Ming, Guan; Fang, Lv

2017-02-01

Biometric identification technology replaces traditional security technology, which has become a trend, and gait recognition also has become a hot spot of research because its feature is difficult to imitate and theft. This paper presents a gait recognition system based on integral outline of human body. The system has three important aspects: the preprocessing of gait image, feature extraction and classification. Finally, using a method of polling to evaluate the performance of the system, and summarizing the problems existing in the gait recognition and the direction of development in the future.

Ambulatory fall-risk assessment: amount and quality of daily-life gait predict falls in older adults.

Science.gov (United States)

van Schooten, Kimberley S; Pijnappels, Mirjam; Rispens, Sietse M; Elders, Petra J M; Lips, Paul; van Dieën, Jaap H

2015-05-01

Ambulatory measurements of trunk accelerations can provide valuable information on the amount and quality of daily-life activities and contribute to the identification of individuals at risk of falls. We compared associations between retrospective and prospective falls with potential risk factors as measured by daily-life accelerometry. In addition, we investigated predictive value of these parameters for 6-month prospective falls. One week of trunk accelerometry (DynaPort MoveMonitor) was obtained in 169 older adults (mean age 75). The amount of daily activity and quality of gait were determined and validated questionnaires on fall-risk factors, grip strength, and trail making test were obtained. Six-month fall incidence was obtained retrospectively by recall and prospectively by fall diaries and monthly telephone contact. Among all participants, 35.5% had a history of ≥1 falls and 34.9% experienced ≥1 falls during 6-month follow-up. Logistic regressions showed that questionnaires, grip strength, and trail making test, as well as the amount and quality of gait, were significantly associated with falls. Significant associations differed between retrospective and prospective analyses although odds ratios indicated similar patterns. Predictive ability based on questionnaires, grip strength, and trail making test (area under the curve .68) improved substantially by accelerometry-derived parameters of the amount of gait (number of strides), gait quality (complexity, intensity, and smoothness), and their interactions (area under the curve .82). Daily-life accelerometry contributes substantially to the identification of individuals at risk of falls, and can predict falls in 6 months with good accuracy. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Neural Pattern Similarity in the Left IFG and Fusiform Is Associated with Novel Word Learning

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Jing Qu

2017-08-01

Full Text Available Previous studies have revealed that greater neural pattern similarity across repetitions is associated with better subsequent memory. In this study, we used an artificial language training paradigm and representational similarity analysis to examine whether neural pattern similarity across repetitions before training was associated with post-training behavioral performance. Twenty-four native Chinese speakers were trained to learn a logographic artificial language for 12 days and behavioral performance was recorded using the word naming and picture naming tasks. Participants were scanned while performing a passive viewing task before training, after 4-day training and after 12-day training. Results showed that pattern similarity in the left pars opercularis (PO and fusiform gyrus (FG before training was negatively associated with reaction time (RT in both word naming and picture naming tasks after training. These results suggest that neural pattern similarity is an effective neurofunctional predictor of novel word learning in addition to word memory.

Neural Pattern Similarity in the Left IFG and Fusiform Is Associated with Novel Word Learning

Science.gov (United States)

Qu, Jing; Qian, Liu; Chen, Chuansheng; Xue, Gui; Li, Huiling; Xie, Peng; Mei, Leilei

2017-01-01

Previous studies have revealed that greater neural pattern similarity across repetitions is associated with better subsequent memory. In this study, we used an artificial language training paradigm and representational similarity analysis to examine whether neural pattern similarity across repetitions before training was associated with post-training behavioral performance. Twenty-four native Chinese speakers were trained to learn a logographic artificial language for 12 days and behavioral performance was recorded using the word naming and picture naming tasks. Participants were scanned while performing a passive viewing task before training, after 4-day training and after 12-day training. Results showed that pattern similarity in the left pars opercularis (PO) and fusiform gyrus (FG) before training was negatively associated with reaction time (RT) in both word naming and picture naming tasks after training. These results suggest that neural pattern similarity is an effective neurofunctional predictor of novel word learning in addition to word memory. PMID:28878640

Robot-Crawler: Statically Balanced Gaits

Directory of Open Access Journals (Sweden)

S. Parasuraman

2012-12-01

Full Text Available This paper presents a new statically balanced walking technique for a robot-crawler. The gait design and the control of the robot crawler aim to achieve stability while walking. This statically balanced gait has to be designed in a different fashion to a wheeled robot, as there are discrete changes in the support of the robot when its legs are lifted or placed on the ground. The stability of the robot depends on how the legs are positioned relative to the body and also on the sequence and timing with which the legs are lifted and placed. In order to reduce the risk of stability loss while walking, a measure for the robot stability (so-called stability margin is typically used in the gait and motion planning. In this paper different biological behaviours of four-legged animals are studied and mapped on a quad-legrobot-crawler. Experiments were carried out on the forward walking gaits of lizards and horses. Based on these results, the stability margins of different gaits are discussed and compared.

First signs of elderly gait for women.

Science.gov (United States)

Kaczmarczyk, Katarzyna; Wiszomirska, Ida; Błażkiewicz, Michalina; Wychowański, Michał; Wit, Andrzej

2017-06-27

The aims of this study have been twofold: to attempt to reduce the number of spatiotemporal parameters used for describing gait through the factor analysis and component analysis; and to explore the critical age of decline for other gait parameters for healthy women. A total of 106 women (aged ≥ 40 years old (N = 76) and ≤ 31 years old (N = 30)) were evaluated using a pressure-sensitive mat (Zebris Medical System, Tübingen, Germany) for collecting spatiotemporal gait parameters. The factor analysis identified 2 factors - labelled Time and Rhythm - that accounted for 72% of the variation in significant free-gait parameters; the principal component analysis identified 4 of these parameters that permit full clinical evaluation of gait quality. No difference was found between the groups in terms of the values of parameters reflecting the temporal nature of gait (Rhythm), namely step time, stride time and cadence, whereas significant differences were found for total double support phase (p gait, we selected 3 parameters: total double support, stride time and velocity. We concluded that the women taking part in the experiment manifested significant signs of senile gait after the age of 60 years old, with the first symptoms thereof already manifesting themselves after 50 years of age. We show that among 26 spatiotemporal parameters that may be used for characterizing gait, at least a half of them may be omitted in the assessment of gait correctness; a finding that may be useful in clinical practice. The finding that the onset of senile gait occurs in the case of women after the age of 60 years old, in turn, may be useful in evaluating the ability for performing types of physical work that mainly require ambulation. Med Pr 2017;68(4):441-448. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Repetition suppression and multi-voxel pattern similarity differentially track implicit and explicit visual memory.

Science.gov (United States)

Ward, Emily J; Chun, Marvin M; Kuhl, Brice A

2013-09-11

Repeated exposure to a visual stimulus is associated with corresponding reductions in neural activity, particularly within visual cortical areas. It has been argued that this phenomenon of repetition suppression is related to increases in processing fluency or implicit memory. However, repetition of a visual stimulus can also be considered in terms of the similarity of the pattern of neural activity elicited at each exposure--a measure that has recently been linked to explicit memory. Despite the popularity of each of these measures, direct comparisons between the two have been limited, and the extent to which they differentially (or similarly) relate to behavioral measures of memory has not been clearly established. In the present study, we compared repetition suppression and pattern similarity as predictors of both implicit and explicit memory. Using functional magnetic resonance imaging, we scanned 20 participants while they viewed and categorized repeated presentations of scenes. Repetition priming (facilitated categorization across repetitions) was used as a measure of implicit memory, and subsequent scene recognition was used as a measure of explicit memory. We found that repetition priming was predicted by repetition suppression in prefrontal, parietal, and occipitotemporal regions; however, repetition priming was not predicted by pattern similarity. In contrast, subsequent explicit memory was predicted by pattern similarity (across repetitions) in some of the same occipitotemporal regions that exhibited a relationship between priming and repetition suppression; however, explicit memory was not related to repetition suppression. This striking double dissociation indicates that repetition suppression and pattern similarity differentially track implicit and explicit learning.

Accuracy and reliability of observational gait analysis data: judgments of push-off in gait after stroke.

Science.gov (United States)

McGinley, Jennifer L; Goldie, Patricia A; Greenwood, Kenneth M; Olney, Sandra J

2003-02-01

Physical therapists routinely observe gait in clinical practice. The purpose of this study was to determine the accuracy and reliability of observational assessments of push-off in gait after stroke. Eighteen physical therapists and 11 subjects with hemiplegia following a stroke participated in the study. Measurements of ankle power generation were obtained from subjects following stroke using a gait analysis system. Concurrent videotaped gait performances were observed by the physical therapists on 2 occasions. Ankle power generation at push-off was scored as either normal or abnormal using two 11-point rating scales. These observational ratings were correlated with the measurements of peak ankle power generation. A high correlation was obtained between the observational ratings and the measurements of ankle power generation (mean Pearson r=.84). Interobserver reliability was moderately high (mean intraclass correlation coefficient [ICC (2,1)]=.76). Intraobserver reliability also was high, with a mean ICC (2,1) of.89 obtained. Physical therapists were able to make accurate and reliable judgments of push-off in videotaped gait of subjects following stroke using observational assessment. Further research is indicated to explore the accuracy and reliability of data obtained with observational gait analysis as it occurs in clinical practice.

Generating high-speed dynamic running gaits in a quadruped robot using an evolutionary search.

Science.gov (United States)

Krasny, Darren P; Orin, David E

2004-08-01

Over the past several decades, there has been a considerable interest in investigating high-speed dynamic gaits for legged robots. While much research has been published, both in the biomechanics and engineering fields regarding the analysis of these gaits, no single study has adequately characterized the dynamics of high-speed running as can be achieved in a realistic, yet simple, robotic system. The goal of this paper is to find the most energy-efficient, natural, and unconstrained gallop that can be achieved using a simulated quadrupedal robot with articulated legs, asymmetric mass distribution, and compliant legs. For comparison purposes, we also implement the bound and canter. The model used here is planar, although we will show that it captures much of the predominant dynamic characteristics observed in animals. While it is not our goal to prove anything about biological locomotion, the dynamic similarities between the gaits we produce and those found in animals does indicate a similar underlying dynamic mechanism. Thus, we will show that achieving natural, efficient high-speed locomotion is possible even with a fairly simple robotic system. To generate the high-speed gaits, we use an efficient evolutionary algorithm called set-based stochastic optimization. This algorithm finds open-loop control parameters to generate periodic trajectories for the body. Several alternative methods are tested to generate periodic trajectories for the legs. The combined solutions found by the evolutionary search and the periodic-leg methods, over a range of speeds up to 10.0 m/s, reveal "biological" characteristics that are emergent properties of the underlying gaits.

Greater Fall Risk in Elderly Women Than in Men Is Associated With Increased Gait Variability During Multitasking.

Science.gov (United States)

Johansson, Jonas; Nordström, Anna; Nordström, Peter

2016-06-01

As 90% of fractures are caused by falls, and as fractures are more common in elderly women than in elderly men, a better understanding of potential sex differences in fall rates and underlying mechanisms is needed. The purpose of this study was to determine whether women are more prone than men to falling, and to evaluate whether the risk of falling is associated with variations in gait patterns. The cohort for this prospective observational study consisted of 1390 community-dwelling men and women aged 70 years, examined in a health survey between July 2012 and November 2014. Gait patterns were measured using a computerized walkway system during normal-speed, fast-speed, and dual-task trials. Triaxial accelerometers were used to collect objective data on physical activity, and self-reported fall data were collected by telephone 6 and 12 months after examination. Incident low-energy falls were defined as unexpected events in which participants came to rest on the ground. During the follow-up period, 148 study participants (88 women, 60 men; P = .01) reported falls. After adjusting for multiple confounders, including objective measures of physical activity, socioeconomic factors, cardiovascular disease, and cognitive function, the odds ratio for falling in women was 1.49 (95% confidence interval [CI] 1.02-2.19). Variations in gait pattern were significantly (20%-40%) increased in fallers compared with nonfallers during the dual-task trial for step width, step length, stride length, step time, stance time, stride velocity, and single support time (all P women showed 15% to 35% increased variability in all of these gait parameters during the dual-task trial compared with men (all P women were at greater risk of falls compared with their male counterparts. This increased risk was associated with increased variation in gait pattern during dual-task activities, and may contribute to women's greater fracture risk compared with men. Copyright © 2016 AMDA – The

Screw-Home Movement of the Tibiofemoral Joint during Normal Gait: Three-Dimensional Analysis.

Science.gov (United States)

Kim, Ha Yong; Kim, Kap Jung; Yang, Dae Suk; Jeung, Sang Wook; Choi, Han Gyeol; Choy, Won Sik

2015-09-01

The purpose of this study was to evaluate the screw-home movement at the tibiofemoral joint during normal gait by utilizing the 3-dimensional motion capture technique. Fifteen young males and fifteen young females (total 60 knee joints) who had no history of musculoskeletal disease or a particular gait problem were included in this study. Two more markers were attached to the subject in addition to the Helen-Hayes marker set. Thus, two virtual planes, femoral coronal plane (P f ) and tibial coronal plane (P t ), were created by Skeletal Builder software. This study measured the 3-dimensional knee joint movement in the sagittal, coronal, and transverse planes of these two virtual planes (P f and P t ) during normal gait. With respect to kinematics and kinetics, both males and females showed normal adult gait patterns, and the mean difference in the temporal gait parameters was not statistically significant (p > 0.05). In the transverse plane, the screw-home movement occurred as expected during the pre-swing phase and the late-swing phase at an angle of about 17°. However, the tibia rotated externally with respect to the femur, rather than internally, while the knee joint started to flex during the loading response (paradoxical screw-home movement), and the angle was 6°. Paradoxical screw-home movement may be an important mechanism that provides stability to the knee joint during the remaining stance phase. Obtaining the kinematic values of the knee joint during gait can be useful in diagnosing and treating the pathological knee joints.

Development of quadruped walking locomotion gait generator using a hybrid method

International Nuclear Information System (INIS)

Jasni, F; Shafie, A A

2013-01-01

The earth, in many areas is hardly reachable by the wheeled or tracked locomotion system. Thus, walking locomotion system is becoming a favourite option for mobile robot these days. This is because of the ability of walking locomotion to move on the rugged and unlevel terrains. However, to develop a walking locomotion gait for a robot is not a simple task. Central Pattern Generator (CPGs) method is a biological inspired method that is introduced as a method to develop the gait for the walking robot recently to tackle the issue faced by the conventional method of pre-designed trajectory based method. However, research shows that even the CPG method do have some limitations. Thus, in this paper, a hybrid method that combines CPG and the pre-designed trajectory based method is introduced to develop a walking gait for quadruped walking robot. The 3-D foot trajectories and the joint angle trajectories developed using the proposed method are compared with the data obtained via the conventional method of pre-designed trajectory to confirm the performance

How multi segmental patterns deviate in spastic diplegia from typical developed.

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Zago, Matteo; Sforza, Chiarella; Bona, Alessia; Cimolin, Veronica; Costici, Pier Francesco; Condoluci, Claudia; Galli, Manuela

2017-10-01

The relationship between gait features and coordination in children with Cerebral Palsy is not sufficiently analyzed yet. Principal Component Analysis can help in understanding motion patterns decomposing movement into its fundamental components (Principal Movements). This study aims at quantitatively characterizing the functional connections between multi-joint gait patterns in Cerebral Palsy. 65 children with spastic diplegia aged 10.6 (SD 3.7) years participated in standardized gait analysis trials; 31 typically developing adolescents aged 13.6 (4.4) years were also tested. To determine if posture affects gait patterns, patients were split into Crouch and knee Hyperextension group according to knee flexion angle at standing. 3D coordinates of hips, knees, ankles, metatarsal joints, pelvis and shoulders were submitted to Principal Component Analysis. Four Principal Movements accounted for 99% of global variance; components 1-3 explained major sagittal patterns, components 4-5 referred to movements on frontal plane and component 6 to additional movement refinements. Dimensionality was higher in patients than in controls (p<0.01), and the Crouch group significantly differed from controls in the application of components 1 and 4-6 (p<0.05), while the knee Hyperextension group in components 1-2 and 5 (p<0.05). Compensatory strategies of children with Cerebral Palsy (interactions between main and secondary movement patterns), were objectively determined. Principal Movements can reduce the effort in interpreting gait reports, providing an immediate and quantitative picture of the connections between movement components. Copyright © 2017 Elsevier Ltd. All rights reserved.

Exoskeleton-assisted gait training to improve gait in individuals with spinal cord injury: a pilot randomized study.

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Chang, Shuo-Hsiu; Afzal, Taimoor; Berliner, Jeffrey; Francisco, Gerard E

2018-01-01

Robotic wearable exoskeletons have been utilized as a gait training device in persons with spinal cord injury. This pilot study investigated the feasibility of offering exoskeleton-assisted gait training (EGT) on gait in individuals with incomplete spinal cord injury (iSCI) in preparation for a phase III RCT. The objective was to assess treatment reliability and potential efficacy of EGT and conventional physical therapy (CPT). Forty-four individuals were screened, and 13 were eligible to participate in the study. Nine participants consented and were randomly assigned to receive either EGT or CPT with focus on gait. Subjects received EGT or CPT, five sessions a week (1 h/session daily) for 3 weeks. American Spinal Injury Association (ASIA) Lower Extremity Motor Score (LEMS), 10-Meter Walk Test (10MWT), 6-Minute Walk Test (6MWT), Timed Up and Go (TUG) test, and gait characteristics including stride and step length, cadence and stance, and swing phase durations were assessed at the pre- and immediate post- training. Mean difference estimates with 95% confidence intervals were used to analyze the differences. After training, improvement was observed in the 6MWT for the EGT group. The CPT group showed significant improvement in the TUG test. Both the EGT and the CPT groups showed significant increase in the right step length. EGT group also showed improvement in the stride length. EGT could be applied to individuals with iSCI to facilitate gait recovery. The subjects were able to tolerate the treatment; however, exoskeleton size range may be a limiting factor in recruiting larger cohort of patients. Future studies with larger sample size are needed to investigate the effectiveness and efficacy of exoskeleton-assisted gait training as single gait training and combined with other gait training strategies. Clinicaltrials.org, NCT03011099, retrospectively registered on January 3, 2017.

Geomfinder: a multi-feature identifier of similar three-dimensional protein patterns: a ligand-independent approach.

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Núñez-Vivanco, Gabriel; Valdés-Jiménez, Alejandro; Besoaín, Felipe; Reyes-Parada, Miguel

2016-01-01

Since the structure of proteins is more conserved than the sequence, the identification of conserved three-dimensional (3D) patterns among a set of proteins, can be important for protein function prediction, protein clustering, drug discovery and the establishment of evolutionary relationships. Thus, several computational applications to identify, describe and compare 3D patterns (or motifs) have been developed. Often, these tools consider a 3D pattern as that described by the residues surrounding co-crystallized/docked ligands available from X-ray crystal structures or homology models. Nevertheless, many of the protein structures stored in public databases do not provide information about the location and characteristics of ligand binding sites and/or other important 3D patterns such as allosteric sites, enzyme-cofactor interaction motifs, etc. This makes necessary the development of new ligand-independent methods to search and compare 3D patterns in all available protein structures. Here we introduce Geomfinder, an intuitive, flexible, alignment-free and ligand-independent web server for detailed estimation of similarities between all pairs of 3D patterns detected in any two given protein structures. We used around 1100 protein structures to form pairs of proteins which were assessed with Geomfinder. In these analyses each protein was considered in only one pair (e.g. in a subset of 100 different proteins, 50 pairs of proteins can be defined). Thus: (a) Geomfinder detected identical pairs of 3D patterns in a series of monoamine oxidase-B structures, which corresponded to the effectively similar ligand binding sites at these proteins; (b) we identified structural similarities among pairs of protein structures which are targets of compounds such as acarbose, benzamidine, adenosine triphosphate and pyridoxal phosphate; these similar 3D patterns are not detected using sequence-based methods; (c) the detailed evaluation of three specific cases showed the versatility

Gait transition and oxygen consumption in swimming striped surfperch Embiotoca lateralis Agassiz

DEFF Research Database (Denmark)

Cannas, M.; Schaefer, J.; Domenici, P.

2006-01-01

A flow-through respirometer and swim tunnel was used to estimate the gait transition speed (Up-c) of striped surfperch Embiotoca lateralis, a labriform swimmer, and to investigate metabolic costs associated with gait transition. The Up-c was defined as the lowest speed at which fish decrease...... the use of pectoral fins significantly. While the tail was first recruited for manoeuvring at relatively low swimming speeds, the use of the tail at these low speeds [as low as 0·75 body (fork) lengths s-1, LF s-1) was rare (..., either in addition to pectoral fins or during burst-and-coast mode. Oxygen consumption increased exponentially with swimming speeds up to gait transition, and then levelled off. Similarly, cost of transport (CT) decreased with increasing speed, and then levelled off near Up-c. When speeds =Up...

Distal muscle activity alterations during the stance phase of gait in restless leg syndrome (RLS) patients.

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Dafkin, Chloe; Green, Andrew; Olivier, Benita; McKinon, Warrick; Kerr, Samantha

2018-05-01

To assess if there is a circadian variation in electromyographical (EMG) muscle activity during gait in restless legs syndrome (RLS) patients and healthy control participants. Gait assessment was done in 14 RLS patients and 13 healthy control participants in the evening (PM) and the morning (AM). Muscle activity was recorded bilaterally from the tibialis anterior (TA), lateral gastrocnemius (GL), rectus femoris (RF) and biceps femoris (BF) muscles. A circadian variation during the stance phase in only TA (PM > AM, p  Controls, p < 0.05) during early stance and decreased GL activity (RLS < Controls, p < 0.01) during terminal stance in comparison to control participants in the evening. No other significant differences were noted between RLS patients and control participants. Activation of GL during the swing phase was noted in 79% of RLS patients and in 23% of control participants in the morning compared to 71% and 38% in the evening, respectively. EMG muscle activity shows no circadian variation in RLS patients. Evening differences in gait muscle activation patterns between RLS patients and control participants are evident. These results extend our knowledge about alterations in spinal processing during gait in RLS. A possible explanation for these findings is central pattern generator sensitization caused by increased sensitivity in cutaneous afferents in RLS patients. Copyright © 2018 Elsevier B.V. All rights reserved.

Muscle coordination in healthy subjects during floor walking and stair climbing in robot assisted gait training.

Science.gov (United States)

Hussein, S; Schmidt, H; Volkmar, M; Werner, C; Helmich, I; Piorko, F; Krüger, J; Hesse, S

2008-01-01

The aim of gait rehabilitation is a restoration of an independent gait and improvement of daily life walking functions. Therefore the specific patterns, that are to be relearned, must be practiced to stimulate the learning process of the central nervous system (CNS). The Walking Simulator HapticWalker allows for the training of arbitrary gait trajectories of daily life. To evaluate the quality of the training a total of 9 subjects were investigated during free floor walking and stair climbing and during the same tasks in two different training modes on the HapticWalker: 1) with and 2) without vertical center of mass (CoM) motion. Electromyograms (EMG) of 8 gait relevant muscles were measured and muscle activation was compared for the various training modes. Besides the muscle activation as an indicator for the quality of rehabilitation training the study investigates if a cancellation of the vertical CoM movement by adaption of the footplate trajectory is feasible i.e. the muscle activation patterns for the two training modes on the HapticWalker agree. Results show no significant differences in activation timing between the training modes. This indicates the feasibility of using a passive patient suspension and emulate the vertical CoM motion by trajectory adaption of the footplates. The muscle activation timing during HapticWalker training shows important characteristics observed in physiological free walking though a few differences can still remain.

Inertial Sensor-Based Gait Recognition: A Review

Science.gov (United States)

Sprager, Sebastijan; Juric, Matjaz B.

2015-01-01

With the recent development of microelectromechanical systems (MEMS), inertial sensors have become widely used in the research of wearable gait analysis due to several factors, such as being easy-to-use and low-cost. Considering the fact that each individual has a unique way of walking, inertial sensors can be applied to the problem of gait recognition where assessed gait can be interpreted as a biometric trait. Thus, inertial sensor-based gait recognition has a great potential to play an important role in many security-related applications. Since inertial sensors are included in smart devices that are nowadays present at every step, inertial sensor-based gait recognition has become very attractive and emerging field of research that has provided many interesting discoveries recently. This paper provides a thorough and systematic review of current state-of-the-art in this field of research. Review procedure has revealed that the latest advanced inertial sensor-based gait recognition approaches are able to sufficiently recognise the users when relying on inertial data obtained during gait by single commercially available smart device in controlled circumstances, including fixed placement and small variations in gait. Furthermore, these approaches have also revealed considerable breakthrough by realistic use in uncontrolled circumstances, showing great potential for their further development and wide applicability. PMID:26340634

Overground robot assisted gait trainer for the treatment of drug-resistant freezing of gait in Parkinson disease.

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Pilleri, Manuela; Weis, Luca; Zabeo, Letizia; Koutsikos, Konstantinos; Biundo, Roberta; Facchini, Silvia; Rossi, Simonetta; Masiero, Stefano; Antonini, Angelo

2015-08-15

Freezing of Gait (FOG) is a frequent and disabling feature of Parkinson disease (PD). Gait rehabilitation assisted by electromechanical devices, such as training on treadmill associated with sensory cues or assisted by gait orthosis have been shown to improve FOG. Overground robot assisted gait training (RGT) has been recently tested in patients with PD with improvement of several gait parameters. We here evaluated the effectiveness of RGT on FOG severity and gait abnormalities in PD patients. Eighteen patients with FOG resistant to dopaminergic medications were treated with 15 sessions of RGT and underwent an extensive clinical evaluation before and after treatment. The main outcome measures were FOG questionnaire (FOGQ) global score and specific tasks for gait assessment, namely 10 meter walking test (10 MWT), Timed Up and Go test (TUG) and 360° narrow turns (360 NT). Balance was also evaluated through Fear of Falling Efficacy Scale (FFES), assessing self perceived stability and Berg Balance Scale (BBS), for objective examination. After treatment, FOGQ score was significantly reduced (P=0.023). We also found a significant reduction of time needed to complete TUG, 10 MWT, and 360 NT (P=0.009, 0.004 and 0.04, respectively). By contrast the number of steps and the number of freezing episodes recorded at each gait task did not change. FFES and BBS scores also improved, with positive repercussions on performance on daily activity and quality of life. Our results indicate that RGT is a useful strategy for the treatment of drug refractory FOG. Copyright © 2015 Elsevier B.V. All rights reserved.

Classification of rhythmic locomotor patterns in electromyographic signals using fuzzy sets

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Thrasher Timothy A

2011-12-01

Full Text Available Abstract Background Locomotor control is accomplished by a complex integration of neural mechanisms including a central pattern generator, spinal reflexes and supraspinal control centres. Patterns of muscle activation during walking exhibit an underlying structure in which groups of muscles seem to activate in united bursts. Presented here is a statistical approach for analyzing Surface Electromyography (SEMG data with the goal of classifying rhythmic "burst" patterns that are consistent with a central pattern generator model of locomotor control. Methods A fuzzy model of rhythmic locomotor patterns was optimized and evaluated using SEMG data from a convenience sample of four able-bodied individuals. As well, two subjects with pathological gait participated: one with Parkinson's Disease, and one with incomplete spinal cord injury. Subjects walked overground and on a treadmill while SEMG was recorded from major muscles of the lower extremities. The model was fit to half of the recorded data using non-linear optimization and validated against the other half of the data. The coefficient of determination, R2, was used to interpret the model's goodness of fit. Results Using four fuzzy burst patterns, the model was able to explain approximately 70-83% of the variance in muscle activation during treadmill gait and 74% during overground gait. When five burst functions were used, one function was found to be redundant. The model explained 81-83% of the variance in the Parkinsonian gait, and only 46-59% of the variance in spinal cord injured gait. Conclusions The analytical approach proposed in this article is a novel way to interpret multichannel SEMG signals by reducing the data into basic rhythmic patterns. This can help us better understand the role of rhythmic patterns in locomotor control.

Exercises to Improve Gait Abnormalities

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... Articles Directories Videos Resources Contact Exercises to Improve Gait Abnormalities Home » Article Categories » Exercise and Fitness Font Size: A A A A Exercises to Improve Gait Abnormalities Next Page The manner of how a ...

Neural Global Pattern Similarity Underlies True and False Memories.

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Ye, Zhifang; Zhu, Bi; Zhuang, Liping; Lu, Zhonglin; Chen, Chuansheng; Xue, Gui

2016-06-22

The neural processes giving rise to human memory strength signals remain poorly understood. Inspired by formal computational models that posit a central role of global matching in memory strength, we tested a novel hypothesis that the strengths of both true and false memories arise from the global similarity of an item's neural activation pattern during retrieval to that of all the studied items during encoding (i.e., the encoding-retrieval neural global pattern similarity [ER-nGPS]). We revealed multiple ER-nGPS signals that carried distinct information and contributed differentially to true and false memories: Whereas the ER-nGPS in the parietal regions reflected semantic similarity and was scaled with the recognition strengths of both true and false memories, ER-nGPS in the visual cortex contributed solely to true memory. Moreover, ER-nGPS differences between the parietal and visual cortices were correlated with frontal monitoring processes. By combining computational and neuroimaging approaches, our results advance a mechanistic understanding of memory strength in recognition. What neural processes give rise to memory strength signals, and lead to our conscious feelings of familiarity? Using fMRI, we found that the memory strength of a given item depends not only on how it was encoded during learning, but also on the similarity of its neural representation with other studied items. The global neural matching signal, mainly in the parietal lobule, could account for the memory strengths of both studied and unstudied items. Interestingly, a different global matching signal, originated from the visual cortex, could distinguish true from false memories. The findings reveal multiple neural mechanisms underlying the memory strengths of events registered in the brain. Copyright © 2016 the authors 0270-6474/16/366792-11$15.00/0.

VASTUS LATERALIS OBLIQUE ACTIVITY DURING GAIT OF SUBJECTS WITH PATELLOFEMORAL PAIN

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Gilmar Moraes Santos

Full Text Available ABSTRACT Introduction: So far, little is known about the behavior of electromyographic activity of vastus lateralis oblique muscle during treadmill gait in subjects with and without patellofemoral pain syndrome. Objective: The purpose of this study was to investigate the electromyographic activity of the patellar stabilizers muscles and the angle of the knee joint flexion in subjects with and without patellofemoral pain syndrome. Method: Fifteen subjects without (21 ± 3 years and 12 with patellofemoral pain syndrome (20 ± 2 years were evaluated. The electromyographic activity and flexion angle of the knee joint were obtained during gait on the treadmill with a 5 degree inclination. Results: The knee flexion angle was significantly lower in the subjects with patellofemoral pain syndrome when compared with the healthy controls. The electromyographic activity of vastus lateralis longus was significantly greater during gait on the treadmill with inclination in subjects with patellofemoral pain syndrome. The results also showed that the electromyographic activity of vastus lateralis oblique and vastus medialis oblique were similar in both groups, regardless of the condition (with/without inclination. Conclusion: We have shown that knee kinematics during gait differs among patients with and without patellofemoral pain syndrome and healthy controls and that a different motor strategy persists even when the pain is no longer present. In addition, the findings suggested that the vastus lateralis oblique has a minor role in patellar stability during gait.

Association of Gait Characteristics and Depression in Patients with Parkinson's Disease Assessed in Goal-Directed Locomotion Task

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Kincses, Péter; Karádi, Kázmér; Feldmann, Ádám; Dorn, Krisztina; Aschermann, Zsuzsanna; Szolcsányi, Tibor; Csathó, Árpád

2017-01-01

Introduction. In the genesis of Parkinson's disease (PD) clinical phenomenology the exact nature of the association between bradykinesia and affective variables is unclear. In the present study, we analyzed the gait characteristics and level of depression in PD and healthy volunteers. Methods. Patients with PD (n = 48) and healthy controls (n = 52) were recruited for the present study. Walking speed, stride length, and cadence were compared between groups while participants completed a goal-directed locomotion task under visually controlled (VC) and visually noncontrolled conditions (VnC). Results. Significantly higher depression scores were found in PD comparing to healthy control groups. In PD, depression was associated with gait components in the VC wherein the place of the target was visible. In contrast, in healthy subjects the depression was associated with gait components in VnC wherein the location and image of the target were memorized and recalled. In patients with PD and depression, the visually deprived multitask augments the rate of cadence and diminishes stride length, while velocity remains relatively unchanged. The depression associated with gait characteristics as a comorbid affective factor in PD, and that impairs the coherence of gait pattern. Conclusion. The relationship between depression and gait parameters appears to indicate that PD not only is a neurological disease but also incorporates affective disturbances that associate with the regulation of gait characteristics. PMID:28293444

Asymmetry of Anticipatory Postural Adjustment During Gait Initiation

OpenAIRE

Hiraoka, Koichi; Hatanaka, Ryota; Nikaido, Yasutaka; Jono, Yasutomo; Nomura, Yoshifumi; Tani, Keisuke; Chujo, Yuta

2014-01-01

The purpose of this study was to investigate the asymmetry of anticipatory postural adjustment (APA) during gait initiation and to determine whether the process of choosing the initial swing leg affects APA during gait initiation. The participants initiated gait with the leg indicated by a start tone or initiated gait with the leg spontaneously chosen. The dependent variables of APA were not significantly different among the condition of initiating gait with the preferred leg indicated by the...

Specific smartphone usage and cognitive performance affect gait characteristics during free-living and treadmill walking.

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Niederer, Daniel; Bumann, Anke; Mühlhauser, Yvonne; Schmitt, Mareike; Wess, Katja; Engeroff, Tobias; Wilke, Jan; Vogt, Lutz; Banzer, Winfried

2018-04-06

Mobile phone tasks like texting, typing, and dialling during walking are known to impact gait characteristics. Beyond that, the effects of performing smartphone-typical actions like researching and taking self-portraits (selfie) on gait have not been investigated yet. We aimed to investigate the effects of smartphone usage on relevant gait characteristics and to reveal potential association of basic cognitive and walking plus smartphone dual-task abilities. Our cross-sectional, cross-over study on physically active, healthy participants was performed on two days, interrupted by a 24-h washout in between. Assessments were: 1) Cognitive testing battery consisting of the trail making test (TMT A and B) and the Stroop test 2) Treadmill walking under five smartphone usage conditions: no use (control condition), reading, dialling, internet searching and taking a selfie in randomized order. Kinematic and kinetic gait characteristics were assessed to estimate conditions influence. In our sample of 36 adults (24.6 ± 1 years, 23 female, 13 male), ANCOVAs followed by post-hoc t-tests revealed that smartphone usage impaired all tested gait characteristics: gait speed (decrease, all conditions): F = 54.7, p smartphone usage was systematically associated with the TMT B time regarding cadence and double stride length for reading (r = -0.37), dialling (r = -0.35) and taking a selfie (r = -0.34). Smartphone usage substantially impacts walking characteristics in most situations. Changes of gait patterns indicate higher cognitive loads and lower awareness. Copyright © 2018 Elsevier B.V. All rights reserved.

The Required Coefficient of Friction for evaluating gait alterations in people with Multiple Sclerosis during gait.

Science.gov (United States)

Pacifici, Ilaria; Galli, Manuela; Kleiner, Ana Francisca Rozin; Corona, Federica; Coghe, Giancarlo; Marongiu, Elisabetta; Loi, Andrea; Crisafulli, Antonio; Cocco, Eleonora; Marrosu, Maria Giovanna; Pau, Massimiliano

2016-11-01

Required Coefficient of Friction (RCOF) is one of the most critical gait parameters associated to the occurrence of slipping in individuals affected by neurological disorders characterized by balance impairments. This study aims to calculate RCOF in people with Multiple Sclerosis (MS) on the basis of three-dimensional Gait Analysis (GA) data. This study enrolls 22 people with MS (pwMS) who were characterized by an Expanded Disability Status Score in the range 1.5-6 and 10 healthy controls (HC). All participants underwent to three-dimensional GA from which we extracted kinematic and kinetic data (i.e. the Ground Reaction Forces, GRF, and joint moments and powers in the sagittal plane). RCOF was calculated as the ratio of the shear to normal GRF components during the stance phase of gait cycle, and normalized by the walking velocity. Thus, the following variables were extracted: first peak (named P1COF), valley (named V1COF), and second peak (named P2COF) in RCOF curve; also computating the maximum ankle dorsi-plantarflexion moment (MOMmax) and the maximum ankle joint power (PWRmax). Our data revealed that P2COF results are significantly lower in pwMS when compared to HC (p=0.043; Z=-2.025). In pwMS, the study found a moderate, positive correlation between V1COF and MOMmax (r=0.558; pFriction during mid stance and push off phases is critically important to determine whether the frictional capabilities of foot/floor interface are sufficient to prevent slips in pwMS. The impaired ankle moment in MS group causes increased P2COF in comparison to HC, increasing the risk of slipping in the critical phase of transmission of the developed forces to kinematic chain. Also, the correlation analysis among RCOF values and kinetic variables describe the interplay between V1COF and MOMmax: the higher V1COF is, the higher is MOMmax; and the different correlation the study found between COF and kinetic parameters in MS and HC group highlightes the different gait patterns of the two

Effect of Cue Timing and Modality on Gait Initiation in Parkinson Disease With Freezing of Gait.

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Lu, Chiahao; Amundsen Huffmaster, Sommer L; Tuite, Paul J; Vachon, Jacqueline M; MacKinnon, Colum D

2017-07-01

To examine the effects of cue timing, across 3 sensory modalities, on anticipatory postural adjustments (APAs) during gait initiation in people with Parkinson disease (PD). Observational study. Biomechanics research laboratory. Individuals with idiopathic PD (N=25; 11 with freezing of gait [FOG]) were studied in the off-medication state (12-h overnight withdrawal). Gait initiation was tested without cueing (self-initiated) and with 3 cue timing protocols: fixed delay (3s), random delay (4-12s), and countdown (3-2-1-go, 1-s intervals) across 3 sensory modalities (acoustic, visual, and vibrotactile). The incidence and spatiotemporal characteristics of APAs during gait initiation were analyzed, including vertical ground reaction forces and center of pressure. All cue timings and modalities increased the incidence and amplitude of APAs compared with self-initiated stepping. Acoustic and visual cues, but not vibrotactile stimulation, improved the timing of APAs. Fixed delay or countdown timing protocols were more effective at decreasing APA durations than random delay cues. Cue-evoked improvements in APA timing, but not amplitude, correlated with the level of impairment during self-initiated gait. Cues did not improve the late push-off phase in the FOG group. External cueing improves gait initiation in PD regardless of cue timing, modality, or clinical phenotype (with and without FOG). Acoustic or visual cueing with predictive timing provided the greatest improvements in gait initiation; therefore, these protocols may provide the best outcomes when applied by caregivers or devices. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Challenges and Specifications for Robust Face and Gait Recognition Systems for Surveillance Application

Directory of Open Access Journals (Sweden)

BUCIU Ioan

2014-05-01

Full Text Available Automated person recognition (APR based on biometric signals addresses the process of automatically recognize a person according to his physiological traits (face, voice, iris, fingerprint, ear shape, body odor, electroencephalogram – EEG, electrocardiogram, or hand geometry, or behavioural patterns (gait, signature, hand-grip, lip movement. The paper aims at briefly presenting the current challenges for two specific non-cooperative biometric approaches, namely face and gait biometrics as well as approaches that consider combination of the two in the attempt of a more robust system for accurate APR, in the context of surveillance application. Open problems from both sides are also pointed out.

Gait COP trajectory of left side hip-dislocation and scoliotic patient using ankle-foot orthoses

Science.gov (United States)

Chong, Albert K.; Alrikabi, Redha; Milburn, Peter

2017-07-01

Plantar pressure-sensing mats and insole plantar sensor pads are ideal low-cost alternatives to force plates for capturing plantar COP excursion during gait. The acquired COP traces, in the form of pedobarographic images are favored by many clinicians and allied health professionals for evaluation of foot loading and balance in relation to foot biomechanics, foot injury, foot deformation, and foot ulceration. Researchers have recommended the use of COP trace for the biomechanical study of the deformed foot and lower-limb to improve orthosis design and testing. A correctly designed orthoses improves mobility and reduces pain in the foot, lower limb and lower spine region during gait. The research was carried out to evaluate the performance of two types of orthosis, namely: a custom-molded orthosis and an over-the-counter molded orthosis to determine the quality of gait of an adult scoliotic patient. COP trace patterns were compared with those of a healthy adult and showed the design of the custom-molded orthosis resulted in an improved quality of movements and provided enhanced stability for the deformed left foot during gait.

The effects of dual tasking on gait synchronization during over-ground side-by-side walking.

Science.gov (United States)

Zivotofsky, Ari Z; Bernad-Elazari, Hagar; Grossman, Pnina; Hausdorff, Jeffrey M

2018-03-23

Recent studies have shown that gait synchronization during natural walking is not merely anecdotal, but it is a repeatable phenomenon that is quantifiable and is apparently related to available sensory feedback modalities. However, the mechanisms underlying this phase-locking of gait have only recently begun to be investigated. For example, it is not known what role, if any, attention plays. We employed a dual tasking paradigm in order to investigate the role attention plays in gait synchronization. Sixteen pairs of subjects walked under six conditions that manipulated the available sensory feedback and the degree of difficulty of the dual task, i.e., the attention. Movement was quantified using a trunk-mounted tri-axial accelerometer. A gait synchronization index (GSI) was calculated in order to quantify the degree of synchronization of the gait pattern. A simple dual task resulted in an increased level of synchronization, whereas a more complex dual task lead to a reduction in synchronization. Handholding increased synchronization, compared to the same attention condition without handholding. These results indicate that in order for two walkers to synchronize, some level of attention is apparently required, such that a relatively complex dual task utilizes enough attentional resources to reduce the occurrence of synchronization. Copyright © 2018 Elsevier B.V. All rights reserved.

Flexible Piezoelectric Sensor-Based Gait Recognition

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Youngsu Cha

2018-02-01

Full Text Available Most motion recognition research has required tight-fitting suits for precise sensing. However, tight-suit systems have difficulty adapting to real applications, because people normally wear loose clothes. In this paper, we propose a gait recognition system with flexible piezoelectric sensors in loose clothing. The gait recognition system does not directly sense lower-body angles. It does, however, detect the transition between standing and walking. Specifically, we use the signals from the flexible sensors attached to the knee and hip parts on loose pants. We detect the periodic motion component using the discrete time Fourier series from the signal during walking. We adapt the gait detection method to a real-time patient motion and posture monitoring system. In the monitoring system, the gait recognition operates well. Finally, we test the gait recognition system with 10 subjects, for which the proposed system successfully detects walking with a success rate over 93 %.

Tai Chi and vestibular rehabilitation improve vestibulopathic gait via different neuromuscular mechanisms: Preliminary report

Directory of Open Access Journals (Sweden)

Parker Stephen W

2005-02-01

Full Text Available Abstract Background Vestibular rehabilitation (VR is a well-accepted exercise program intended to remedy balance impairment caused by damage to the peripheral vestibular system. Alternative therapies, such as Tai Chi (TC, have recently gained popularity as a treatment for balance impairment. Although VR and TC can benefit people with vestibulopathy, the degree to which gait improvements may be related to neuromuscular adaptations of the lower extremities for the two different therapies are unknown. Methods We examined the relationship between lower extremity neuromuscular function and trunk control in 36 older adults with vestibulopathy, randomized to 10 weeks of either VR or TC exercise. Time-distance measures (gait speed, step length, stance duration and step width, lower extremity sagittal plane mechanical energy expenditures (MEE, and trunk sagittal and frontal plane kinematics (peak and range of linear and angular velocity, were measured. Results Although gait time-distance measures were improved in both groups following treatment, no significant between-groups differences were observed for the MEE and trunk kinematic measures. Significant within groups changes, however, were observed. The TC group significantly increased ankle MEE contribution and decreased hip MEE contribution to total leg MEE, while no significant changes were found within the VR group. The TC group exhibited a positive relationship between change in leg MEE and change in trunk velocity peak and range, while the VR group exhibited a negative relationship. Conclusion Gait function improved in both groups consistent with expectations of the interventions. Differences in each group's response to therapy appear to suggest that improved gait function may be due to different neuromuscular adaptations resulting from the different interventions. The TC group's improvements were associated with reorganized lower extremity neuromuscular patterns, which appear to promote a faster

Detecting gait abnormalities after concussion or mild traumatic brain injury: A systematic review of single-task, dual-task, and complex gait.

Science.gov (United States)

Fino, Peter C; Parrington, Lucy; Pitt, Will; Martini, Douglas N; Chesnutt, James C; Chou, Li-Shan; King, Laurie A

2018-05-01

While a growing number of studies have investigated the effects of concussion or mild traumatic brain injury (mTBI) on gait, many studies use different experimental paradigms and outcome measures. The path for translating experimental studies for objective clinical assessments of gait is unclear. This review asked 2 questions: 1) is gait abnormal after concussion/mTBI, and 2) what gait paradigms (single-task, dual-task, complex gait) detect abnormalities after concussion. Data sources included MEDLINE/PubMed, Scopus, Web of Science, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) accessed on March 14, 2017. Original research articles reporting gait outcomes in people with concussion or mTBI were included. Studies of moderate, severe, or unspecified TBI, and studies without a comparator were excluded. After screening 233 articles, 38 studies were included and assigned to one or more sections based on the protocol and reported outcomes. Twenty-six articles reported single-task simple gait outcomes, 24 reported dual-task simple gait outcomes, 21 reported single-task complex gait outcomes, and 10 reported dual-task complex gait outcomes. Overall, this review provides evidence for two conclusions: 1) gait is abnormal acutely after concussion/mTBI but generally resolves over time; and 2) the inconsistency of findings, small sample sizes, and small number of studies examining homogenous measures at the same time-period post-concussion highlight the need for replication across independent populations and investigators. Future research should concentrate on dual-task and complex gait tasks, as they showed promise for detecting abnormal locomotor function outside of the acute timeframe. Additionally, studies should provide detailed demographic and clinical characteristics to enable more refined comparisons across studies. Copyright © 2018 Elsevier B.V. All rights reserved.

Gait analysis in forensic medicine

DEFF Research Database (Denmark)

Larsen, Peter K; Simonsen, Erik B; Lynnerup, Niels

2008-01-01

Recordings from video surveillance systems are used as evidence from crime scenes. It would be useful to perform comparisons between disguised perpetrators and suspects based on their gait. We applied functional anatomical and biomechanical knowledge to analyze the gait of perpetrators, as record...

Feasibility of external rhythmic cueing with the Google Glass for improving gait in people with Parkinson's disease.

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Zhao, Yan; Nonnekes, Jorik; Storcken, Erik J M; Janssen, Sabine; van Wegen, Erwin E H; Bloem, Bastiaan R; Dorresteijn, Lucille D A; van Vugt, Jeroen P P; Heida, Tjitske; van Wezel, Richard J A

2016-06-01

New mobile technologies like smartglasses can deliver external cues that may improve gait in people with Parkinson's disease in their natural environment. However, the potential of these devices must first be assessed in controlled experiments. Therefore, we evaluated rhythmic visual and auditory cueing in a laboratory setting with a custom-made application for the Google Glass. Twelve participants (mean age = 66.8; mean disease duration = 13.6 years) were tested at end of dose. We compared several key gait parameters (walking speed, cadence, stride length, and stride length variability) and freezing of gait for three types of external cues (metronome, flashing light, and optic flow) and a control condition (no-cue). For all cueing conditions, the subjects completed several walking tasks of varying complexity. Seven inertial sensors attached to the feet, legs and pelvis captured motion data for gait analysis. Two experienced raters scored the presence and severity of freezing of gait using video recordings. User experience was evaluated through a semi-open interview. During cueing, a more stable gait pattern emerged, particularly on complicated walking courses; however, freezing of gait did not significantly decrease. The metronome was more effective than rhythmic visual cues and most preferred by the participants. Participants were overall positive about the usability of the Google Glass and willing to use it at home. Thus, smartglasses like the Google Glass could be used to provide personalized mobile cueing to support gait; however, in its current form, auditory cues seemed more effective than rhythmic visual cues.

Predictors of Gait Speeds and the Relationship of Gait Speeds to Falls in Men and Women with Parkinson Disease

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Samuel T. Nemanich

2013-01-01

Full Text Available Gait difficulties and falls are commonly reported in people with Parkinson disease (PD. Reduction in gait speed is a major characteristic of Parkinsonian gait, yet little is known about its underlying determinants, its ability to reflect an internal reservation about walking, or its relationship to falls. To study these issues, we selected age, disease severity, and nonmotor factors (i.e., depression, quality of life, balance confidence, and exercise beliefs and attitudes to predict self-selected (SELF, fast-as-possible (FAST, and the difference (DIFF between these walking speeds in 78 individuals with PD. We also examined gender differences in gait speeds and evaluated how gait speeds were related to a retrospective fall report. Age, disease severity, and balance confidence were strong predictors of SELF, FAST, and, to a lesser extent, DIFF. All three parameters were strongly associated with falling. DIFF was significantly greater in men compared to women and was significantly associated with male but not female fallers. The results supported the clinical utility of using a suite of gait speed parameters to provide insight into the gait difficulties and differentiating between fallers in people with PD.

Synergy of EMG patterns in gait as an objective measure of muscle selectivity in children with spastic cerebral palsy.

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Zwaan, Esther; Becher, Jules G; Harlaar, Jaap

2012-01-01

Selective motor control (SMC) is an important determinant of functioning in cerebral palsy (CP). Currently its assessment is based on subjective clinical tests with a low sensitivity. Electromyography (EMG) profiles during gait represent muscle coordination and might be used to assess SMC. EMG measurements during gait were processed into a measure of extensor synergy and thigh synergy. This was obtained in two groups of children with CP, and 30 typically developing children. Extensor synergy in CP was higher (0.95) than in healthy children (0.77), thigh synergy was almost equal in both groups. GMFM scores in the first group of 39 children with CP did not correlate to EMG based synergy measures. In a second group of 38 children with CP, a clear relation of clinical SMC score with extensor synergy was found, but only a weak relation with thigh synergy. Although an extensor synergy was validated at group level, our results present no convincing evidence for the use of EMG during gait to assess SMC in individual subjects with CP. Since gait involves both synergistic and selective contractions, the inherent motor control properties of this task will not allow for an assessment of selectivity comparable to the ability to perform isolated movements. Nevertheless, our results support the sensitive nature of EMG to represent an aberrant motor control in CP. Copyright © 2011 Elsevier B.V. All rights reserved.

Effect of therapeutic horseback riding on balance and gait of people with multiple sclerosis.

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Muñoz-Lasa, Susana; Ferriero, Giorgio; Valero, Raquel; Gomez-Muñiz, Fernando; Rabini, Alessia; Varela, Enrique

2011-01-01

Exercise therapy is an important part of symptomatic and supportive treatment in patients with multiple sclerosis (PwMS). According to the literature, equine-assisted therapies--such as therapeutic horseback riding (THR) and hippotherapy (HT)--are exercise therapies that can have positive physical effects on coordination, muscle tone, postural alignment, stiffness/flexibility, endurance and strength, correcting abnormal movement patterns and improving gait and balance. While HT is known to have a positive effect on balance in PwMS, data about THR are limited. The aim of the present work was to determine the effect of THR on the balance and gait of ambulatory PwMS. Twenty-seven PwMS were included in the study. Patients were divided into two groups: 12 underwent THR and 15 traditional physiotherapy (for both groups, two series of 10 weekly sessions were performed). Before and after the study period, the following outcome measures were applied: Extended Disability Status Scale (EDSS), Barthel Index, Tinetti Performance-Oriented Mobility Assessment (POMA). In addition, patients of the THR group underwent a gait analysis to assess spatiotemporal gait parameters and ground reaction forces. The THR group showed a significant improvement in POMA scores (p<0.005) and two gait parameters: stride time (p<0.04) and ground reaction forces (p<0.01). No statistically significant change was found in the control group. The results of the study show that THR can improve balance and gait of ambulatory PwMS. Findings are preliminary, but promising and in line with the recent literature.

Gait, posture and cognition in Parkinson's disease

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Alessandra Ferreira Barbosa

Full Text Available ABSTRACT Gait disorders and postural instability are the leading causes of falls and disability in Parkinson's disease (PD. Cognition plays an important role in postural control and may interfere with gait and posture assessment and treatment. It is important to recognize gait, posture and balance dysfunctions by choosing proper assessment tools for PD. Patients at higher risk of falling must be referred for rehabilitation as early as possible, because antiparkinsonian drugs and surgery do not improve gait and posture in PD.

Gait Disorders In Patients After Polytrauma

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Jakušonoka Ruta

2015-04-01

Full Text Available Evaluation of the gait of patients after polytrauma is important, as it indicates the ability of patients to the previous activities and work. The aim of our study was to evaluate the gait of patients with lower limb injuries in the medium-term after polytrauma. Three-dimensional instrumental gait analysis was performed in 26 polytrauma patients (16 women and 10 men; mean age 38.6 years, 14 to 41 months after the trauma. Spatio-temporal parameters, motions in pelvis and lower extremities joints in sagittal plane and vertical load ground reaction force were analysed. Gait parameters in polytrauma patients were compared with a healthy control group. Polytrauma patients in the injured side had decreased step length, cadence, hip extension, maximum knee flexion, vertical load ground reaction force, and increased stance time and pelvic anterior tilt; in the uninjured side they had decreased step length, cadence, maximum knee flexion, vertical load ground reaction force and increased stance time (p < 0.05. The use of the three-dimensional instrumental gait analysis in the evaluation of polytrauma patients with lower limb injuries consequences makes it possible to identify the gait disorders not only in the injured, but also in the uninjured side.

Gait stability and variability measures show effects of impaired cognition and dual tasking in frail people

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de Vries Oscar J

2011-01-01

Full Text Available Abstract Background Falls in frail elderly are a common problem with a rising incidence. Gait and postural instability are major risk factors for falling, particularly in geriatric patients. As walking requires attention, cognitive impairments are likely to contribute to an increased fall risk. An objective quantification of gait and balance ability is required to identify persons with a high tendency to fall. Recent studies have shown that stride variability is increased in elderly and under dual task condition and might be more sensitive to detect fall risk than walking speed. In the present study we complemented stride related measures with measures that quantify trunk movement patterns as indicators of dynamic balance ability during walking. The aim of the study was to quantify the effect of impaired cognition and dual tasking on gait variability and stability in geriatric patients. Methods Thirteen elderly with dementia (mean age: 82.6 ± 4.3 years and thirteen without dementia (79.4 ± 5.55 recruited from a geriatric day clinic, walked at self-selected speed with and without performing a verbal dual task. The Mini Mental State Examination and the Seven Minute Screen were administered. Trunk accelerations were measured with an accelerometer. In addition to walking speed, mean, and variability of stride times, gait stability was quantified using stochastic dynamical measures, namely regularity (sample entropy, long range correlations and local stability exponents of trunk accelerations. Results Dual tasking significantly (p Conclusions The observed trunk adaptations were a consistent instability factor. These results support the concept that changes in cognitive functions contribute to changes in the variability and stability of the gait pattern. Walking under dual task conditions and quantifying gait using dynamical parameters can improve detecting walking disorders and might help to identify those elderly who are able to adapt walking

Association of Gait Characteristics and Depression in Patients with Parkinson’s Disease Assessed in Goal-Directed Locomotion Task

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Péter Kincses

2017-01-01

Full Text Available Introduction. In the genesis of Parkinson’s disease (PD clinical phenomenology the exact nature of the association between bradykinesia and affective variables is unclear. In the present study, we analyzed the gait characteristics and level of depression in PD and healthy volunteers. Methods. Patients with PD (n=48 and healthy controls (n=52 were recruited for the present study. Walking speed, stride length, and cadence were compared between groups while participants completed a goal-directed locomotion task under visually controlled (VC and visually noncontrolled conditions (VnC. Results. Significantly higher depression scores were found in PD comparing to healthy control groups. In PD, depression was associated with gait components in the VC wherein the place of the target was visible. In contrast, in healthy subjects the depression was associated with gait components in VnC wherein the location and image of the target were memorized and recalled. In patients with PD and depression, the visually deprived multitask augments the rate of cadence and diminishes stride length, while velocity remains relatively unchanged. The depression associated with gait characteristics as a comorbid affective factor in PD, and that impairs the coherence of gait pattern. Conclusion. The relationship between depression and gait parameters appears to indicate that PD not only is a neurological disease but also incorporates affective disturbances that associate with the regulation of gait characteristics.

TKA patients with unsatisfying knee function show changes in neuromotor synergy pattern but not joint biomechanics.

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Ardestani, Marzieh M; Malloy, Philip; Nam, Denis; Rosenberg, Aaron G; Wimmer, Markus A

2017-12-01

Nearly 20% of patients who have undergone total knee arthroplasty (TKA) report persistent poor knee function. This study explores the idea that, despite similar knee joint biomechanics, the neuro-motor synergies may be different between high-functional and low-functional TKA patients. We hypothesized that (1) high-functional TKA recruit a more complex neuro-motor synergy pattern compared to low-functional TKA and (2) high-functional TKA patients demonstrate more stride-to-stride variability (flexibility) in their synergies. Gait and electromyography (EMG) data were collected during level walking for three groups of participants: (i) high-functional TKA patients (n=13); (ii) low-functional TKA patients (n=13) and (iii) non-operative controls (n=18). Synergies were extracted from EMG data using non-negative matrix factorization. Analysis of variance and Spearman correlation analyses were used to investigate between-group differences in gait and neuro-motor synergies. Results showed that synergy patterns were different among the three groups. Control subjects used 5-6 independent neural commands to execute a gait cycle. High functional TKA patients used 4-5 independent neural commands while low-functional TKA patients relied on only 2-3 independent neural commands to execute a gait cycle. Furthermore, stride-to-stride variability of muscles' response to the neural commands was reduced up to 15% in low-functional TKAs compared to the other two groups. Copyright © 2017 Elsevier Ltd. All rights reserved.

Intensive gait training in toddlers with cerebral palsy: A pilot study

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Anna Herskind

2016-07-01

Full Text Available Background: Reduced muscle growth may be involved in the development of contractures in children with cerebral palsy (CP. Here, we report data from a pilot study of intensive gait training in CP toddlers. Methods: Five children with CP aged 8-30 months performed activity-based gait training for one hour/day, five days/week for three consecutive months. Included children were diagnosed with spastic CP, had a Gross Motor Function Classification System (GMFCS score of I–II, and were not epileptic. All children wore pedometers during training. Before and after the training period, kinematic and qualitative gait analysis, clinical and objective evaluation of spasticity, Gross Motor Function Measure-66 (GMFM-66, and ultrasound of the affected medial gastrocnemius (MG muscle were performed. Two children were also tested before and after three months of receiving only standard care (SC. Results: On average 1410 steps/session were logged during 63 days of training. More steps were achieved at home than at a central facility. During training, MG muscle volume increased significantly, while it decreased for SC children. Gait improved qualitatively in all children, and GMFM-66 score improved in four of the five children. Similar improvements were seen among the SC children. Two children had pathologically increased muscle stiffness prior to training, which was reduced during training. Reflex stiffness was unchanged in all five children. Conclusions: This pilot study suggests that intensive gait training may increase muscle volume, improve walking skills and reduce passive muscle stiffness in toddlers with CP.

A gait stability investigation into FES-assisted paraplegic walking based on the walker tipping index.

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Ming, Dong; Bai, Yanru; Liu, Xiuyun; Qi, Hongzhi; Cheng, Longlong; Wan, Baikun; Hu, Yong; Wong, Yatwa; Luk, Keith D K; Leong, John C Y

2009-12-01

The gait outcome measures used in clinical trials of paraplegic locomotor training determine the effectiveness of improved walking function assisted by the functional electrical stimulation (FES) system. Focused on kinematic, kinetic or physiological changes of paraplegic patients, traditional methods cannot quantify the walking stability or identify the unstable factors of gait in real time. Up until now, the published studies on dynamic gait stability for the effective use of FES have been limited. In this paper, the walker tipping index (WTI) was used to analyze and process gait stability in FES-assisted paraplegic walking. The main instrument was a specialized walker dynamometer system based on a multi-channel strain-gauge bridge network fixed on the frame of the walker. This system collected force information for the handle reaction vector between the patient's upper extremities and the walker during the walking process; the information was then converted into walker tipping index data, which is an evaluation indicator of the patient's walking stability. To demonstrate the potential usefulness of WTI in gait analysis, a preliminary clinical trial was conducted with seven paraplegic patients who were undergoing FES-assisted walking training and seven normal control subjects. The gait stability levels were quantified for these patients under different stimulation patterns and controls under normal walking with knee-immobilization through WTI analysis. The results showed that the walking stability in the FES-assisted paraplegic group was worse than that in the control subject group, with the primary concern being in the anterior-posterior plane. This new technique is practical for distinguishing useful gait information from the viewpoint of stability, and may be further applied in FES-assisted paraplegic walking rehabilitation.

A gait stability investigation into FES-assisted paraplegic walking based on the walker tipping index

Science.gov (United States)

Ming, Dong; Bai, Yanru; Liu, Xiuyun; Qi, Hongzhi; Cheng, Longlong; Wan, Baikun; Hu, Yong; Wong, Yatwa; Luk, Keith D. K.; Leong, John C. Y.

2009-12-01

The gait outcome measures used in clinical trials of paraplegic locomotor training determine the effectiveness of improved walking function assisted by the functional electrical stimulation (FES) system. Focused on kinematic, kinetic or physiological changes of paraplegic patients, traditional methods cannot quantify the walking stability or identify the unstable factors of gait in real time. Up until now, the published studies on dynamic gait stability for the effective use of FES have been limited. In this paper, the walker tipping index (WTI) was used to analyze and process gait stability in FES-assisted paraplegic walking. The main instrument was a specialized walker dynamometer system based on a multi-channel strain-gauge bridge network fixed on the frame of the walker. This system collected force information for the handle reaction vector between the patient's upper extremities and the walker during the walking process; the information was then converted into walker tipping index data, which is an evaluation indicator of the patient's walking stability. To demonstrate the potential usefulness of WTI in gait analysis, a preliminary clinical trial was conducted with seven paraplegic patients who were undergoing FES-assisted walking training and seven normal control subjects. The gait stability levels were quantified for these patients under different stimulation patterns and controls under normal walking with knee-immobilization through WTI analysis. The results showed that the walking stability in the FES-assisted paraplegic group was worse than that in the control subject group, with the primary concern being in the anterior-posterior plane. This new technique is practical for distinguishing useful gait information from the viewpoint of stability, and may be further applied in FES-assisted paraplegic walking rehabilitation.

Gait Stability in Children with Cerebral Palsy

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Bruijn, Sjoerd M.; Millard, Matthew; van Gestel, Leen; Meyns, Pieter; Jonkers, Ilse; Desloovere, Kaat

2013-01-01

Children with unilateral Cerebral Palsy (CP) have several gait impairments, amongst which impaired gait stability may be one. We tested whether a newly developed stability measure (the foot placement estimator, FPE) which does not require long data series, can be used to asses gait stability in typically developing (TD) children as well as…

Office management of gait disorders in the elderly.

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Lam, Robert

2011-07-01

To provide family physicians with an approach to office management of gait disorders in the elderly. Ovid MEDLINE was searched from 1950 to July 2010 using subject headings for gait or neurologic gait disorders combined with physical examination. Articles specific to family practice or family physicians were selected. Relevant review articles and original research were used when appropriate and applicable to the elderly. Gait and balance disorders in the elderly are difficult to recognize and diagnose in the family practice setting because they initially present with subtle undifferentiated manifestations, and because causes are usually multifactorial, with multiple diseases developing simultaneously. To further complicate the issue, these manifestations can be camouflaged in elderly patients by the physiologic changes associated with normal aging. A classification of gait disorders based on sensorimotor levels can be useful in the approach to management of this problem. Gait disorders in patients presenting to family physicians in the primary care setting are often related to joint and skeletal problems (lowest-level disturbances), as opposed to patients referred to neurology specialty clinics with sensory ataxia, myelopathy, multiple strokes, and parkinsonism (lowest-, middle-, and highest-level disturbances). The difficulty in diagnosing gait disorders stems from the challenge of addressing early undifferentiated disease caused by multiple disease processes involving all sensorimotor levels. Patients might present with a nonspecific "cautious" gait that is simply an adaptation of the body to disease limitations. This cautious gait has a mildly flexed posture with reduced arm swing and a broadening of the base of support. This article reviews the focused history (including medication review), practical physical examination, investigations, and treatments that are key to office management of gait disorders. Family physicians will find it helpful to classify gait

Human Gait Recognition Based on Multiview Gait Sequences

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Xiaxi Huang

2008-05-01

Full Text Available Most of the existing gait recognition methods rely on a single view, usually the side view, of the walking person. This paper investigates the case in which several views are available for gait recognition. It is shown that each view has unequal discrimination power and, therefore, should have unequal contribution in the recognition process. In order to exploit the availability of multiple views, several methods for the combination of the results that are obtained from the individual views are tested and evaluated. A novel approach for the combination of the results from several views is also proposed based on the relative importance of each view. The proposed approach generates superior results, compared to those obtained by using individual views or by using multiple views that are combined using other combination methods.

Effects of Visual Feedback Distortion on Gait Adaptation: Comparison of Implicit Visual Distortion Versus Conscious Modulation on Retention of Motor Learning.

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Kim, Seung-Jae; Ogilvie, Mitchell; Shimabukuro, Nathan; Stewart, Trevor; Shin, Joon-Ho

2015-09-01

Visual feedback can be used during gait rehabilitation to improve the efficacy of training. We presented a paradigm called visual feedback distortion; the visual representation of step length was manipulated during treadmill walking. Our prior work demonstrated that an implicit distortion of visual feedback of step length entails an unintentional adaptive process in the subjects' spatial gait pattern. Here, we investigated whether the implicit visual feedback distortion, versus conscious correction, promotes efficient locomotor adaptation that relates to greater retention of a task. Thirteen healthy subjects were studied under two conditions: (1) we implicitly distorted the visual representation of their gait symmetry over 14 min, and (2) with help of visual feedback, subjects were told to walk on the treadmill with the intent of attaining the gait asymmetry observed during the first implicit trial. After adaptation, the visual feedback was removed while subjects continued walking normally. Over this 6-min period, retention of preserved asymmetric pattern was assessed. We found that there was a greater retention rate during the implicit distortion trial than that of the visually guided conscious modulation trial. This study highlights the important role of implicit learning in the context of gait rehabilitation by demonstrating that training with implicit visual feedback distortion may produce longer lasting effects. This suggests that using visual feedback distortion could improve the effectiveness of treadmill rehabilitation processes by influencing the retention of motor skills.

Reshaping of Gait Coordination by Robotic Intervention in Myelopathy Patients After Surgery

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Puentes, Sandra; Kadone, Hideki; Kubota, Shigeki; Abe, Tetsuya; Shimizu, Yukiyo; Marushima, Aiki; Sankai, Yoshiyuki; Yamazaki, Masashi; Suzuki, Kenji

2018-01-01

The Ossification of the Posterior Longitudinal Ligament (OPLL) is an idiopathic degenerative spinal disease which may cause motor deficit. For patients presenting myelopathy or severe stenosis, surgical decompression is the treatment of choice; however, despite adequate decompression residual motor impairment is found in some cases. After surgery, there is no therapeutic approach available for this population. The Hybrid Assistive Limb® (HAL) robot suit is a unique powered exoskeleton designed to predict, support, and enhance the lower extremities performance of patients using their own bioelectric signals. This approach has been used for spinal cord injury and stroke patients where the walking performance improved. However, there is no available data about gait kinematics evaluation after HAL therapy. Here we analyze the effect of HAL therapy in OPLL patients in acute and chronic stages after decompression surgery. We found that HAL therapy improved the walking performance for both groups. Interestingly, kinematics evaluation by the analysis of the elevation angles of the thigh, shank, and foot by using a principal component analysis showed that planar covariation, plane orientation, and movement range evaluation improved for acute patients suggesting an improvement in gait coordination. Being the first study performing kinematics analysis after HAL therapy, our results suggest that HAL improved the gait coordination of acute patients by supporting the relearning process and therefore reshaping their gait pattern. PMID:29551960

Hybrid gait training with an overground robot for people with incomplete spinal cord injury: a pilot study.

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Del-Ama, Antonio J; Gil-Agudo, Angel; Pons, José L; Moreno, Juan C

2014-01-01

Locomotor training has proved to provide beneficial effect in terms of mobility in incomplete paraplegic patients. Neuroprosthetic technology can contribute to increase the efficacy of a training paradigm in the promotion of a locomotor pattern. Robotic exoskeletons can be used to manage the unavoidable loss of performance of artificially driven muscles. Hybrid exoskeletons blend complementary robotic and neuro-prosthetic technologies. The aim of this pilot study was to determine the effects of hybrid gait training in three case studies with persons with incomplete spinal cord injury (iSCI) in terms of locomotion performance during assisted gait, patient-robot adaptations, impact on ambulation and assessment of lower limb muscle strength and spasticity. Participants with iSCI received interventions with a hybrid bilateral exoskeleton for 4 days. Assessment of gait function revealed that patients improved the 6 min and 10 m walking tests after the intervention, and further improvements were observed 1 week after the intervention. Muscle examination revealed improvements in knee and hip sagittal muscle balance scores and decreased score in ankle extensor balance. It is concluded that improvements in biomechanical function of the knee joint after the tested overground hybrid gait trainer are coherent with improvements in gait performance.

Feasibility study of a wearable exoskeleton for children: is the gait altered by adding masses on lower limbs?

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Stefano Rossi

Full Text Available We are designing a pediatric exoskeletal ankle robot (pediatric Anklebot to promote gait habilitation in children with Cerebral Palsy (CP. Few studies have evaluated how much or whether the unilateral loading of a wearable exoskeleton may have the unwanted effect of altering significantly the gait. The purpose of this study was to evaluate whether adding masses up to 2.5 kg, the estimated overall added mass of the mentioned device, at the knee level alters the gait kinematics. Ten healthy children and eight children with CP, with light or mild gait impairment, walked wearing a knee brace with several masses. Gait parameters and lower-limb joint kinematics were analyzed with an optoelectronic system under six conditions: without brace (natural gait and with masses placed at the knee level (0.5, 1.0, 1.5, 2.0, 2.5 kg. T-tests and repeated measures ANOVA tests were conducted in order to find noteworthy differences among the trial conditions and between loaded and unloaded legs. No statistically significant differences in gait parameters for both healthy children and children with CP were observed in the five "with added mass" conditions. We found significant differences among "natural gait" and "with added masses" conditions in knee flexion and hip extension angles for healthy children and in knee flexion angle for children with CP. This result can be interpreted as an effect of the mechanical constraint induced by the knee brace rather than the effect associated with load increase. The study demonstrates that the mechanical constraint induced by the brace has a measurable effect on the gait of healthy children and children with CP and that the added mass up to 2.5 kg does not alter the lower limb kinematics. This suggests that wearable devices weighing 25 N or less will not noticeably modify the gait patterns of the population examined here.

Temporal and Spatial Characterization of Gait Pattern in Rodents as an Animal model of Cerebrovascular Lesion

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Jaison D Cucarián

2017-09-01

Full Text Available Animal experimentation is crucial for the advance in the understanding of pathophysiological mechanisms and their application on both clinical diagnosis and neuro-rehabilitation. Particularly, rodent brain lesion is commonly used in the modeling of locomotor, somatosensory and cognitive symptoms. The automated rodent gait analysis has been proposed as a tool for studying locomotor and sensory abilities and its use includes the identification of functional alterations, structural adaptations as well as neuro-rehabilitation mechanisms. From that standpoint, the effectiveness of many therapeutic intervention (i.e. physical exercises has been documented in rodents and humans. The translation from experimental data to clinical conditions requires the continuous collaboration and feedback between researchers and health clinicians looking for the selection of the best rehabilitation protocols obtained from animal research. Here we will show some locomotor alterations, the traditional methods used to assess motor dysfunction and gait abnormalities in rodent models with stroke. The aim of this review is to show some motor deficiencies and some methods used to establish gait disturbances in rodents with cerebrovascular lesion. The review included the search of defined terms (MeSH in PychINFO, Medline and Web of Science, between January 2000 and January 2017. Qualitative and narrative reports, dissertations, end course works and conference resumes were discarded. The review focuses on some clinical signs, their effects on rodent locomotor activity, some methodologies used to create lesion and to study motor function, some assessment methods and some translational aspects.

Gait parameters in patients with diabetes mellitus

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Cristina Elena Prado Teles Fregonesi

2010-02-01

Full Text Available Diabetes mellitus is a chronic disease that results in sensorimotor alterations. These changes affect balance and walking and predispose affected patients to falls. The aim of this review was to identify studies in the recent literature that assess gait parameters and aspects involved in walking. The MEDLINE, SciELO, LILACS and PEDro databases were searched using the following combination of keywords: diabetic neuropathies x gait; diabetes mellitus x gait, and diabetic foot x gait. After the application of selection criteria, 15 articles were retrieved, summarized, discussed, and are included in this review. Diabetic neuropathy was found to lead to deficits in step amplitude, gait velocity and gait cadence on flat surfaces, without sudden changes in direction or stops, and to balance and coordination deficits on inclined and uneven terrain. Diabetic neuropathies also increase plantar pressure rates and lead to difficulties in the terminal stance phase and pre-swing phase due to changes in triceps surae activation. Thus, the next initial contact occurs in an inadequate manner, with the forefoot and without absorption of shocks.

Skeletal and Clinical Effects of Exoskeleton-Assisted Gait

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2015-10-01

robotic exoskeletons to enable gait in individuals with a complete spinal cord injury, the health benefits of exoskeleton -assisted gait have not been...for the use of robotic exoskeletons to enable gait in individuals with a complete spinal cord injury, clinical teams are not provided with...appropriate tools to estimate or predict potential health benefits (e.g. bone health) associated with exoskeleton -assisted gait. What was the impact on other

Estimating Human Physical States from Chronological Gait Features Acquired with RFID Technology

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Yoshihiro UEMURA

2015-11-01

Full Text Available This paper proposes a method to estimate the state of the user to provide proactive hospitality from features of their gait pattern acquired with a Radio Frequency Identifier (RFID system. This method uses RFID readers on each shoe, as well as RFID tags installed on the floor. The ID of each tag is organized as a map, to show the precise position of the user. The reader and tags communicate while the user is walking. We extract feature components which represents gait patterns. Two-way ANOVA test and correlation analysis are conducted to find significant features. We classify the state of the user from these components with the Naȉve Bayes, the Support Vector Machine, and the Random Forest. Compared with each combination of the analysis and the machine learning method, the most efficient way is found to identify the state of the user. The experimental results show that different state of users can be classified appropriately. Finally, variable importance and the feasibility of proposed method are discussed to show potential implications of the proposed approach.

Dual task interference on postural sway, postural transitions and gait in people with Parkinson's disease and freezing of gait.

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de Souza Fortaleza, Ana Claudia; Mancini, Martina; Carlson-Kuhta, Patty; King, Laurie A; Nutt, John G; Chagas, Eliane Ferrari; Freitas, Ismael Forte; Horak, Fay B

2017-07-01

Freezing of gait (FoG) is associated with less automatic gait and more impaired cognition, balance and postural transitions compared to people with PD who do not have FoG. However, it is unknown whether dual-task cost during postural sway, postural transitions (such as gait initiation and turning), and gait are more in subjects with Parkinson's disease (PD) who have freezing of gait (FoG+) compared to those who do not have FoG (FoG-). Here, we hypothesized that the effects of a cognitive dual task on postural sway, postural transitions and gait would be larger in FoG+ than FoG-. Thirty FoG- and 24 FoG+ performed an Instrumented Stand and Walk test in OFF medication state, with and without a secondary cognitive task (serial subtraction by 3s). Measures of postural sway, gait initiation, turning, and walking were extracted using body-worn inertial sensors. FoG+ showed significantly larger dual task cost than FoG- for several gait metrics, but not during postural sway or postural transitions. During walking, FoG+ exhibited a larger dual task cost than FoG- resulting in shorter stride length and slower stride velocity. During standing, FoG+ showed a larger postural sway compared to FoG- and during gait initiation, FoG+, but not FoG-, showed a longer first step duration during the dual-task condition compared to single-task condition (interaction effect, p=0.04). During turning, both groups showed a slower turn peak speed in the dual-task condition compared to single task condition. These findings partly support our hypothesis that dual task cost on walking is greater in FoG+ than FoG-. Copyright © 2017. Published by Elsevier B.V.

Can biomechanical variables predict improvement in crouch gait?

Science.gov (United States)

Hicks, Jennifer L.; Delp, Scott L.; Schwartz, Michael H.

2011-01-01

Many patients respond positively to treatments for crouch gait, yet surgical outcomes are inconsistent and unpredictable. In this study, we developed a multivariable regression model to determine if biomechanical variables and other subject characteristics measured during a physical exam and gait analysis can predict which subjects with crouch gait will demonstrate improved knee kinematics on a follow-up gait analysis. We formulated the model and tested its performance by retrospectively analyzing 353 limbs of subjects who walked with crouch gait. The regression model was able to predict which subjects would demonstrate ‘improved’ and ‘unimproved’ knee kinematics with over 70% accuracy, and was able to explain approximately 49% of the variance in subjects’ change in knee flexion between gait analyses. We found that improvement in stance phase knee flexion was positively associated with three variables that were drawn from knowledge about the biomechanical contributors to crouch gait: i) adequate hamstrings lengths and velocities, possibly achieved via hamstrings lengthening surgery, ii) normal tibial torsion, possibly achieved via tibial derotation osteotomy, and iii) sufficient muscle strength. PMID:21616666

Response of the arterial blood pressure of quadriplegic patients to treadmill gait training