Impact of SCBA size and fatigue from different firefighting work cycles on firefighter gait.
Kesler, Richard M; Bradley, Faith F; Deetjen, Grace S; Angelini, Michael J; Petrucci, Matthew N; Rosengren, Karl S; Horn, Gavin P; Hsiao-Wecksler, Elizabeth T
2018-04-04
Risk of slips, trips and falls in firefighters maybe influenced by the firefighter's equipment and duration of firefighting. This study examined the impact of a four self-contained breathing apparatus (SCBA) three SCBA of increasing size and a prototype design and three work cycles one bout (1B), two bouts with a five-minute break (2B) and two bouts back-to-back (BB) on gait in 30 firefighters. Five gait parameters (double support time, single support time, stride length, step width and stride velocity) were examined pre- and post-firefighting activity. The two largest SCBA resulted in longer double support times relative to the smallest SCBA. Multiple bouts of firefighting activity resulted in increased single and double support time and decreased stride length, step width and stride velocity. These results suggest that with larger SCBA or longer durations of activity, firefighters may adopt more conservative gait patterns to minimise fall risk. Practitioner Summary: The effects of four self-contained breathing apparatus (SCBA) and three work cycles on five gait parameters were examined pre- and post-firefighting activity. Both SCBA size and work cycle affected gait. The two largest SCBA resulted in longer double support times. Multiple bouts of activity resulted in more conservative gait patterns.
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 is small (n = 5) and of varied quality, which means recommendations arising from this evidence base should be interpreted with caution. There is generally weak evidence that suggests that gait plates and orthotic devices with a gait plate extension may assist in the management of a pediatric intoed gait pattern.
Gait parameter control timing with dynamic manual contact or visual cues
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. PMID:26936979
Svehlík, Martin; Kraus, Tanja; Steinwender, Gerhard; Zwick, Ernst B; Linhart, Wolfgang E
2012-06-01
Legg-Calvé-Perthes disease (LCP) severely limits the range of hip motion and hinders a normal gait. Loading of the hip joint is a major consideration in LCP treatment. The aim of this study was to evaluate gait patterns in LCP and identify gait modifications to decrease the load on the affected hip. Forty children with unilateral LCP were divided into three groups based on the time base integral of the hip abductor moments during single stance on the affected side acquired during instrumented 3D gait analysis. X-rays of the affected hip were classified according to Herring and Catterall. Children in the "unloading" group spontaneously adopted a Duchenne-like gait with pelvis elevation, hip abduction and external rotation during single support phase. The "normal-loading" group showed pelvis elevation with a neutral hip position in the frontal plane. In the "overloading" group the pelvis dropped to the swinging limb at the beginning of stance accompanied by prolonged hip adduction. The time base integral of the hip abductor moments during single stance correlated positively with the X-ray classifications of Herring and Catterall, hip abduction angle and age. Older children preferred to walk in hip adduction during single stance, had more impaired hips and tended to overload them. The hip overloading pattern should be avoided in children with LCP. Gait training to unload the hip might become an integral component of conservative treatment in children with LCP.
Gait parameter control timing with dynamic manual contact or visual cues.
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. Copyright © 2016 the American Physiological Society.
Basu, Abhijit; Jain, Niyati; Tolbert, Blanton S.; Komar, Anton A.
2017-01-01
Abstract RNA–protein interactions with physiological outcomes usually rely on conserved sequences within the RNA element. By contrast, activity of the diverse gamma-interferon-activated inhibitor of translation (GAIT)-elements relies on the conserved RNA folding motifs rather than the conserved sequence motifs. These elements drive the translational silencing of a group of chemokine (CC/CXC) and chemokine receptor (CCR) mRNAs, thereby helping to resolve physiological inflammation. Despite sequence dissimilarity, these RNA elements adopt common secondary structures (as revealed by 2D-1H NMR spectroscopy), providing a basis for their interaction with the RNA-binding GAIT complex. However, many of these elements (e.g. those derived from CCL22, CXCL13, CCR4 and ceruloplasmin (Cp) mRNAs) have substantially different affinities for GAIT complex binding. Toeprinting analysis shows that different positions within the overall conserved GAIT element structure contribute to differential affinities of the GAIT protein complex towards the elements. Thus, heterogeneity of GAIT elements may provide hierarchical fine-tuning of the resolution of inflammation. PMID:29069516
Walking stability and sensorimotor function in older people with diabetic peripheral neuropathy.
Menz, Hylton B; Lord, Stephen R; St George, Rebecca; Fitzpatrick, Richard C
2004-02-01
To evaluate, in older people with diabetic peripheral neuropathy (DPN) and in age-matched controls, acceleration patterns of the head and pelvis when walking to determine the effect of lower-limb sensory loss on walking stability. Case-control study. Falls and balance laboratory in Australia. Thirty persons with diabetes mellitus (age range, 55-91 y) and 30 age-matched controls. Acceleration patterns of the head and pelvis were measured while participants walked on a level surface and an irregular walkway. Participants also underwent tests of vision, sensation, strength, reaction time, and balance. Temporospatial gait parameters and variables derived from acceleration signals. Participants with DPN had reduced walking speed, cadence, and step length, and less rhythmic acceleration patterns at the head and pelvis compared with controls. These differences were particularly evident when participants walked on the irregular surface. Participants with DPN also had impaired peripheral sensation, reaction time, and balance. Older people with DPN have an impaired ability to stabilize their body when walking on irregular surfaces, even if they adopt a more conservative gait pattern. These results provide further insights into the role of peripheral sensory input in the control of gait stability, and suggest possible mechanisms underlying the increased risk of falling in older people with diabetic neuropathy.
Mazaheri, Masood; Negahban, Hossein; Soltani, Maryam; Mehravar, Mohammad; Tajali, Shirin; Hessam, Masumeh; Salavati, Mahyar; Kingma, Idsart
2017-08-01
The present experiment was conducted to examine the hypothesis that challenging control through narrow-base walking and/or dual tasking affects ACL-injured adults more than healthy control adults. Twenty male ACL-injured adults and twenty healthy male adults walked on a treadmill at a comfortable speed under two base-of-support conditions, normal-base versus narrow-base, with and without a cognitive task. Gait patterns were assessed using mean and variability of step length and mean and variability of step velocity. Cognitive performance was assessed using the number of correct counts in a backward counting task. Narrow-base walking resulted in a larger decrease in step length and a more pronounced increase in variability of step length and of step velocity in ACL-injured adults than in healthy adults. For most of the gait parameters and for backward counting performance, the dual-tasking effect was similar between the two groups. ACL-injured adults adopt a more conservative and more unstable gait pattern during narrow-base walking. This can be largely explained by deficits of postural control in ACL-injured adults, which impairs gait under more balance-demanding conditions. The observation that the dual-tasking effect did not differ between the groups may be explained by the fact that walking is an automatic process that involves minimal use of attentional resources, even after ACL injury. Clinicians should consider the need to include aspects of terrain complexity, such as walking on a narrow walkway, in gait assessment and training of patients with ACL injury. III.
NASA Astrophysics Data System (ADS)
Son, Yurak; Kamano, Takuya; Yasuno, Takashi; Suzuki, Takayuki; Harada, Hironobu
This paper describes the generation of adaptive gait patterns using new Central Pattern Generators (CPGs) including motor dynamic models for a quadruped robot under various environment. The CPGs act as the flexible oscillators of the joints and make the desired angle of the joints. The CPGs are mutually connected each other, and the sets of their coupling parameters are adjusted by genetic algorithm so that the quadruped robot can realize the stable and adequate gait patterns. As a result of generation, the suitable CPG networks for not only a walking straight gait pattern but also rotation gait patterns are obtained. Experimental results demonstrate that the proposed CPG networks are effective to automatically adjust the adaptive gait patterns for the tested quadruped robot under various environment. Furthermore, the target tracking control based on image processing is achieved by combining the generated gait patterns.
Hardware Development and Locomotion Control Strategy for an Over-Ground Gait Trainer: NaTUre-Gaits.
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.
Hardware Development and Locomotion Control Strategy for an Over-Ground Gait Trainer: NaTUre-Gaits
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. PMID:27170876
Nieuwenhuys, Angela; Papageorgiou, Eirini; Desloovere, Kaat; Molenaers, Guy; De Laet, Tinne
2017-01-01
Experts recently identified 49 joint motion patterns in children with cerebral palsy during a Delphi consensus study. Pattern definitions were therefore the result of subjective expert opinion. The present study aims to provide objective, quantitative data supporting the identification of these consensus-based patterns. To do so, statistical parametric mapping was used to compare the mean kinematic waveforms of 154 trials of typically developing children (n = 56) to the mean kinematic waveforms of 1719 trials of children with cerebral palsy (n = 356), which were classified following the classification rules of the Delphi study. Three hypotheses stated that: (a) joint motion patterns with 'no or minor gait deviations' (n = 11 patterns) do not differ significantly from the gait pattern of typically developing children; (b) all other pathological joint motion patterns (n = 38 patterns) differ from typically developing gait and the locations of difference within the gait cycle, highlighted by statistical parametric mapping, concur with the consensus-based classification rules. (c) all joint motion patterns at the level of each joint (n = 49 patterns) differ from each other during at least one phase of the gait cycle. Results showed that: (a) ten patterns with 'no or minor gait deviations' differed somewhat unexpectedly from typically developing gait, but these differences were generally small (≤3°); (b) all other joint motion patterns (n = 38) differed from typically developing gait and the significant locations within the gait cycle that were indicated by the statistical analyses, coincided well with the classification rules; (c) joint motion patterns at the level of each joint significantly differed from each other, apart from two sagittal plane pelvic patterns. In addition to these results, for several joints, statistical analyses indicated other significant areas during the gait cycle that were not included in the pattern definitions of the consensus study. Based on these findings, suggestions to improve pattern definitions were made.
Papageorgiou, Eirini; Desloovere, Kaat; Molenaers, Guy; De Laet, Tinne
2017-01-01
Experts recently identified 49 joint motion patterns in children with cerebral palsy during a Delphi consensus study. Pattern definitions were therefore the result of subjective expert opinion. The present study aims to provide objective, quantitative data supporting the identification of these consensus-based patterns. To do so, statistical parametric mapping was used to compare the mean kinematic waveforms of 154 trials of typically developing children (n = 56) to the mean kinematic waveforms of 1719 trials of children with cerebral palsy (n = 356), which were classified following the classification rules of the Delphi study. Three hypotheses stated that: (a) joint motion patterns with ‘no or minor gait deviations’ (n = 11 patterns) do not differ significantly from the gait pattern of typically developing children; (b) all other pathological joint motion patterns (n = 38 patterns) differ from typically developing gait and the locations of difference within the gait cycle, highlighted by statistical parametric mapping, concur with the consensus-based classification rules. (c) all joint motion patterns at the level of each joint (n = 49 patterns) differ from each other during at least one phase of the gait cycle. Results showed that: (a) ten patterns with ‘no or minor gait deviations’ differed somewhat unexpectedly from typically developing gait, but these differences were generally small (≤3°); (b) all other joint motion patterns (n = 38) differed from typically developing gait and the significant locations within the gait cycle that were indicated by the statistical analyses, coincided well with the classification rules; (c) joint motion patterns at the level of each joint significantly differed from each other, apart from two sagittal plane pelvic patterns. In addition to these results, for several joints, statistical analyses indicated other significant areas during the gait cycle that were not included in the pattern definitions of the consensus study. Based on these findings, suggestions to improve pattern definitions were made. PMID:28081229
Lack of maintenance of gait pattern as measured by instrumental methods suggests psychogenic gait.
Merello, Marcelo; Ballesteros, Diego; Rossi, Malco; Arena, Julieta; Crespo, Marcos; Cervio, Andres; Cuello Oderiz, Carolina; Rivero, Alberto; Cerquetti, Daniel; Risk, Marcelo; Balej, Jorge
2012-01-01
Fluctuation is a common feature of all psychogenic gait disorder (PGD) patterns. Whether this fluctuation involves only the degree of impairment or whether it affects the gait pattern itself remains an interesting question. We hypothesize that, on repeated measurements, both normal and abnormal gait may present quantitative differences while maintaining their basic underlying pattern; conversely, in psychogenic gait, the basic pattern appears not to be preserved. Using an optoelectronic system, data acquired from 19 normal subjects and 66 patients were applied to train a neural network (NN) and subsequently classify gait patterns into four different groups (normal, ataxic, spastic-paraparetic and parkinsonian). Five patients who fulfilled clinical criteria for psychogenic gait and six controls were then prospectively evaluated on two separate occasions, three months apart. Normal controls and ataxic, parkinsonian or spastic patients were correctly identified by the NN, and categorized within the corresponding groups at baseline as well as at a three-month follow-up evaluation. NN analysis showed that after three months, no PGD patient preserved the gait pattern detected at baseline, even though this finding was not clinically apparent. Modification of gait pattern detected by repeated kinematic measurement and NN analysis could suggest the presence of PGD, particularly in difficult-to-diagnose cases.
Effects of gyrokinesis exercise on the gait pattern of female patients with chronic low back pain
Seo, Kook-Eun; Park, Tae-Jin
2016-01-01
[Purpose] The purpose of the present study was to use kinematic variables to identify the effects of 8/weeks’ performance of a gyrokinesis exercise on the gait pattern of females with chronic low back pain. [Subjects] The subjects of the present study were females in their late 20s to mid 30s who were chronic back pain patients. [Methods] A 3-D motion analysis system was used to measure the changes in their gait patterns between pre and post-gyrokintic exercise. The SPSS 21.0 statistics program was used to perform the paired t-test, to compare the gait patterns of pre-post-gyrokinesis exercise. [Results] In the gait analysis, pre-post-gyrokinesis exercise gait patterns showed statistically significant differences in right and left step length, stride length, right-left step widths, and stride speed. [Conclusion] Gait pattern analysis revealed increases in step length, stride length, and stride speed along with a decrease in step width after 8 weeks of gyrokinesis exercise, demonstrating it improved gait pattern. PMID:27065537
Gait Analysis Methods for Rodent Models of Arthritic Disorders: Reviews and Recommendations
Lakes, Emily H.; Allen, Kyle D.
2016-01-01
Gait analysis is a useful tool to understand behavioral changes in preclinical arthritis models. While observational scoring and spatiotemporal gait parameters are the most widely performed gait analyses in rodents, commercially available systems can now provide quantitative assessments of spatiotemporal patterns. However, inconsistencies remain between testing platforms, and laboratories often select different gait pattern descriptors to report in the literature. Rodent gait can also be described through kinetic and kinematic analyses, but systems to analyze rodent kinetics and kinematics are typically custom made and often require sensitive, custom equipment. While the use of rodent gait analysis rapidly expands, it is important to remember that, while rodent gait analysis is a relatively modern behavioral assay, the study of quadrupedal gait is not new. Nearly all gait parameters are correlated, and a collection of gait parameters is needed to understand a compensatory gait pattern used by the animal. As such, a change in a single gait parameter is unlikely to tell the full biomechanical story; and to effectively use gait analysis, one must consider how multiple different parameters contribute to an altered gait pattern. The goal of this article is to review rodent gait analysis techniques and provide recommendations on how to use these technologies in rodent arthritis models, including discussions on the strengths and limitations of observational scoring, spatiotemporal, kinetic, and kinematic measures. Recognizing rodent gait analysis is an evolving tool, we also provide technical recommendations we hope will improve the utility of these analyses in the future. PMID:26995111
Quadrupedal galloping control for a wide range of speed via vertical impulse scaling.
Park, Hae-Won; Kim, Sangbae
2015-03-25
This paper presents a bio-inspired quadruped controller that allows variable-speed galloping. The controller design is inspired by observations from biological runners. Quadrupedal animals increase the vertical impulse that is generated by ground reaction forces at each stride as running speed increases and the duration of each stance phase reduces, whereas the swing phase stays relatively constant. Inspired by this observation, the presented controller estimates the required vertical impulse at each stride by applying the linear momentum conservation principle in the vertical direction and prescribes the ground reaction forces at each stride. The design process begins with deriving a planar model from the MIT Cheetah 2 robot. A baseline periodic limit cycle is obtained by optimizing ground reaction force profiles and the temporal gait pattern (timing and duration of gait phases). To stabilize the optimized limit cycle, the obtained limit cycle is converted to a state feedback controller by representing the obtained ground reaction force profiles as functions of the state variable, which is monotonically increasing throughout the gait, adding impedance control around the height and pitch trajectories of the obtained limit cycle and introducing a finite state machine and a pattern stabilizer to enforce the optimized gait pattern. The controller that achieves a stable 3 m s(-1) gallop successfully adapts the speed change by scaling the vertical ground reaction force to match the momentum lost by gravity and adding a simple speed controller that controls horizontal speed. Without requiring additional gait optimization processes, the controller achieves galloping at speeds ranging from 3 m s(-1) to 14.9 m s(-1) while respecting the torque limit of the motor used in the MIT Cheetah 2 robot. The robustness of the controller is verified by demonstrating stable running during various disturbances, including 1.49 m step down and 0.18 m step up, as well as random ground height and model parameter variations.
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 these findings, especially towards more individualized and situational diagnoses and therapy.
Feature extraction via KPCA for classification of gait patterns.
Wu, Jianning; Wang, Jue; Liu, Li
2007-06-01
Automated recognition of gait pattern change is important in medical diagnostics as well as in the early identification of at-risk gait in the elderly. We evaluated the use of Kernel-based Principal Component Analysis (KPCA) to extract more gait features (i.e., to obtain more significant amounts of information about human movement) and thus to improve the classification of gait patterns. 3D gait data of 24 young and 24 elderly participants were acquired using an OPTOTRAK 3020 motion analysis system during normal walking, and a total of 36 gait spatio-temporal and kinematic variables were extracted from the recorded data. KPCA was used first for nonlinear feature extraction to then evaluate its effect on a subsequent classification in combination with learning algorithms such as support vector machines (SVMs). Cross-validation test results indicated that the proposed technique could allow spreading the information about the gait's kinematic structure into more nonlinear principal components, thus providing additional discriminatory information for the improvement of gait classification performance. The feature extraction ability of KPCA was affected slightly with different kernel functions as polynomial and radial basis function. The combination of KPCA and SVM could identify young-elderly gait patterns with 91% accuracy, resulting in a markedly improved performance compared to the combination of PCA and SVM. These results suggest that nonlinear feature extraction by KPCA improves the classification of young-elderly gait patterns, and holds considerable potential for future applications in direct dimensionality reduction and interpretation of multiple gait signals.
ERIC Educational Resources Information Center
van Drongelen, Stefan; Dreher, Thomas; Heitzmann, Daniel W. W.; Wolf, Sebastian I.
2013-01-01
To examine gait patterns and gait quality, 7 twins with cerebral palsy were measured preoperatively and after surgical intervention. The aim was to study differences and/or similarities in gait between twins, the influence of personal characteristics and birth conditions, and to describe the development of gait over time after single event…
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.
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.
Quantitative method for gait pattern detection based on fiber Bragg grating sensors
NASA Astrophysics Data System (ADS)
Ding, Lei; Tong, Xinglin; Yu, Lie
2017-03-01
This paper presents a method that uses fiber Bragg grating (FBG) sensors to distinguish the temporal gait patterns in gait cycles. Unlike most conventional methods that focus on electronic sensors to collect those physical quantities (i.e., strains, forces, pressure, displacements, velocity, and accelerations), the proposed method utilizes the backreflected peak wavelength from FBG sensors to describe the motion characteristics in human walking. Specifically, the FBG sensors are sensitive to external strain with the result that their backreflected peak wavelength will be shifted according to the extent of the influence of external strain. Therefore, when subjects walk in different gait patterns, the strains on FBG sensors will be different such that the magnitude of the backreflected peak wavelength varies. To test the reliability of the FBG sensor platform for gait pattern detection, the gold standard method using force-sensitive resistors (FSRs) for defining gait patterns is introduced as a reference platform. The reliability of the FBG sensor platform is determined by comparing the detection results between the FBG sensors and FSRs platforms. The experimental results show that the FBG sensor platform is reliable in gait pattern detection and gains high reliability when compared with the reference platform.
Gait patterns in hemiplegic patients with equinus foot deformity.
Manca, M; Ferraresi, G; Cosma, M; Cavazzuti, L; Morelli, M; Benedetti, M G
2014-01-01
Equinus deformity of the foot is a common feature of hemiplegia, which impairs the gait pattern of patients. The aim of the present study was to explore the role of ankle-foot deformity in gait impairment. A hierarchical cluster analysis was used to classify the gait patterns of 49 chronic hemiplegic patients with equinus deformity of the foot, based on temporal-distance parameters and joint kinematic measures obtained by an innovative protocol for motion assessment in the sagittal, frontal, and transverse planes, synthesized by parametrical analysis. Cluster analysis identified five subgroups of patients with homogenous levels of dysfunction during gait. Specific joint kinematic abnormalities were found, according to the speed of progression in each cluster. Patients with faster walking were those with less ankle-foot complex impairment or with reduced range of motion of ankle-foot complex, that is with a stiff ankle-foot complex. Slow walking was typical of patients with ankle-foot complex instability (i.e., larger motion in all the planes), severe equinus and hip internal rotation pattern, and patients with hip external rotation pattern. Clustering of gait patterns in these patients is helpful for a better understanding of dysfunction during gait and delivering more targeted treatment.
Horst, F; Mildner, M; Schöllhorn, W I
2017-10-01
Although a hunch about the individuality of human movements generally exists, differences in gait patterns between individuals are often neglected. To date, only a few studies distinguished individual gait patterns in terms of uniqueness and emphasised the relevance of individualised diagnoses and therapy. However, small sample sizes have been a limitation on identifying subjects based on gait patterns, and little is known about the permanence of subject-specific characteristics over time. The purpose of this study was (1) to prove the uniqueness of individual gait patterns within a larger sample and (2) to prove the long-term permanence of individual gait patterns. A sample of 128 healthy participants each walked a distance of 10m barefoot 10 times. Two force plates recorded the ground reaction forces during a double step at a self-selected walking speed. A subsample of 46 participants repeated this procedure after a period of 7-16 months. The application of support vector machines resulted in classification rates of 99.8% (1278 out of 1280) and 99.4% (914 out of 920) for the initial subject-classification and the subsample follow-up-classification, respectively. The results showed that gait patterns based on time-continuous ground reaction forces were unique to an individual and could be differentiated from those of other individuals. Support vector machines classified gait patterns to the corresponding individual almost error-free. Hence, human gait is not only different between individuals but also exhibits unique individual characteristics that are persistent over years. Our findings provide evidence for the individual nature of human walking and emphasise the need to evaluate individualised clinical approaches for diagnoses and therapy. Copyright © 2017 Elsevier B.V. All rights reserved.
Astephen, J L; Deluzio, K J
2005-02-01
Osteoarthritis of the knee is related to many correlated mechanical factors that can be measured with gait analysis. Gait analysis results in large data sets. The analysis of these data is difficult due to the correlated, multidimensional nature of the measures. A multidimensional model that uses two multivariate statistical techniques, principal component analysis and discriminant analysis, was used to discriminate between the gait patterns of the normal subject group and the osteoarthritis subject group. Nine time varying gait measures and eight discrete measures were included in the analysis. All interrelationships between and within the measures were retained in the analysis. The multidimensional analysis technique successfully separated the gait patterns of normal and knee osteoarthritis subjects with a misclassification error rate of <6%. The most discriminatory feature described a static and dynamic alignment factor. The second most discriminatory feature described a gait pattern change during the loading response phase of the gait cycle. The interrelationships between gait measures and between the time instants of the gait cycle can provide insight into the mechanical mechanisms of pathologies such as knee osteoarthritis. These results suggest that changes in frontal plane loading and alignment and the loading response phase of the gait cycle are characteristic of severe knee osteoarthritis gait patterns. Subsequent investigations earlier in the disease process may suggest the importance of these factors to the progression of knee osteoarthritis.
A New Classification of Diabetic Gait Pattern Based on Cluster Analysis of Biomechanical Data
Sawacha, Zimi; Guarneri, Gabriella; Avogaro, Angelo; Cobelli, Claudio
2010-01-01
Background The diabetic foot, one of the most serious complications of diabetes mellitus and a major risk factor for plantar ulceration, is determined mainly by peripheral neuropathy. Neuropathic patients exhibit decreased stability while standing as well as during dynamic conditions. A new methodology for diabetic gait pattern classification based on cluster analysis has been proposed that aims to identify groups of subjects with similar patterns of gait and verify if three-dimensional gait data are able to distinguish diabetic gait patterns from one of the control subjects. Method The gait of 20 nondiabetic individuals and 46 diabetes patients with and without peripheral neuropathy was analyzed [mean age 59.0 (2.9) and 61.1(4.4) years, mean body mass index (BMI) 24.0 (2.8), and 26.3 (2.0)]. K-means cluster analysis was applied to classify the subjects' gait patterns through the analysis of their ground reaction forces, joints and segments (trunk, hip, knee, ankle) angles, and moments. Results Cluster analysis classification led to definition of four well-separated clusters: one aggregating just neuropathic subjects, one aggregating both neuropathics and non-neuropathics, one including only diabetes patients, and one including either controls or diabetic and neuropathic subjects. Conclusions Cluster analysis was useful in grouping subjects with similar gait patterns and provided evidence that there were subgroups that might otherwise not be observed if a group ensemble was presented for any specific variable. In particular, we observed the presence of neuropathic subjects with a gait similar to the controls and diabetes patients with a long disease duration with a gait as altered as the neuropathic one. PMID:20920432
Perez-Rizo, Enrique; Trincado-Alonso, Fernando; Pérez-Nombela, Soraya; Del Ama-Espinosa, Antonio; Jiménez-Díaz, Fernando; Lozano-Berrio, Vicente; Gil-Agudo, Angel
2017-01-01
Specific biomechanical models have been developed to study gait using crutches. Clinical application of these models is needed in adult spinal cord injury (SCI) population walking with different patterns of gait with crutches to prevent overuse shoulder injuries. To apply a biomechanical model in a clinical environment to analyze shoulder in adult SCI patients walking with two different patterns of gait with crutches: two point reciprocal gait (RG) and swing-through gait (SG). Load cells were fixed to the distal ends and forearm cuffs of a pair of crutches. An active markers system was used for kinematics. Five cycles for each gait pattern were analyzed applying a biomechanical model of the upper limbs. Fifteen subjects with SCI were analyzed. The flexo-extension range of motion was significantly greater when using SG (p < 0.01). Similarly, the superior, posterior and medial forces were significantly stronger for SG in all 3 directions. Flexion, adduction and internal rotation torques were also greater in SG (p < 0.01). A biomechanical model was successfully applied to study shoulder biomechanics in adult patients with SCI walking with crutches in two different gait patterns. Greater loads exerted on the shoulder walking with SG were confirmed compared to RG.
NASA Astrophysics Data System (ADS)
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.
Gray matter volume and dual-task gait performance in mild cognitive impairment.
Doi, Takehiko; Blumen, Helena M; Verghese, Joe; Shimada, Hiroyuki; Makizako, Hyuma; Tsutsumimoto, Kota; Hotta, Ryo; Nakakubo, Sho; Suzuki, Takao
2017-06-01
Dual-task gait performance is impaired in older adults with mild cognitive impairment, but the brain substrates associated with dual-task gait performance are not well-established. The relationship between gray matter and gait speed under single-task and dual-task conditions (walking while counting backward) was examined in 560 seniors with mild cognitive impairment (non-amnestic mild cognitive impairment: n = 270; mean age = 72.4 yrs., 63.6 % women; amnestic mild cognitive impairment: n = 290; mean age = 73.4 yrs., 45.4 % women). Multivariate covariance-based analyses of magnetic resonance imaging data, adjusted for potential confounders including single-task gait speed, were performed to identify gray matter patterns associated with dual-task gait speed. There were no differences in gait speed or cognitive performance during dual-task gait between individuals with non-amnestic mild cognitive impairment and amnestic mild cognitive impairment. Overall, increased dual-task gait speed was associated with a gray matter pattern of increased volume in medial frontal gyrus, superior frontal gyrus, anterior cingulate, cingulate, precuneus, fusiform gyrus, middle occipital gyrus, inferior temporal gyrus and middle temporal gyrus. The relationship between dual-task gait speed and brain substrates also differed by mild cognitive impairment subtype. Our study revealed a pattern of gray matter regions associated with dual-task performance. Although dual-task gait performance was similar in amnestic and non-amnestic mild cognitive impairment, the gray matter patterns associated with dual-task gait performance differed by mild cognitive impairment subtype. These findings suggest that the brain substrates supporting dual-task gait performance in amnestic and non-amnestic subtypes are different, and consequently may respond differently to interventions, or require different interventions.
Gray matter volume and dual-task gait performance in mild cognitive impairment
Blumen, Helena M.; Verghese, Joe; Shimada, Hiroyuki; Makizako, Hyuma; Tsutsumimoto, Kota; Hotta, Ryo; Nakakubo, Sho; Suzuki, Takao
2017-01-01
Dual-task gait performance is impaired in older adults with mild cognitive impairment, but the brain substrates associated with dual-task gait performance are not well-established. The relationship between gray matter and gait speed under single-task and dual-task conditions (walking while counting backward) was examined in 560 seniors with mild cognitive impairment (non-amnestic mild cognitive impairment: n = 270; mean age = 72.4 yrs., 63.6 % women; amnestic mild cognitive impairment: n = 290; mean age = 73.4 yrs., 45.4 % women). Multivariate covariance-based analyses of magnetic resonance imaging data, adjusted for potential confounders including single-task gait speed, were performed to identify gray matter patterns associated with dual-task gait speed. There were no differences in gait speed or cognitive performance during dual-task gait between individuals with non-amnestic mild cognitive impairment and amnestic mild cognitive impairment. Overall, increased dual-task gait speed was associated with a gray matter pattern of increased volume in medial frontal gyrus, superior frontal gyrus, anterior cingulate, cingulate, precuneus, fusiform gyrus, middle occipital gyrus, inferior temporal gyrus and middle temporal gyrus. The relationship between dual-task gait speed and brain substrates also differed by mild cognitive impairment subtype. Our study revealed a pattern of gray matter regions associated with dual-task performance. Although dual-task gait performance was similar in amnestic and non-amnestic mild cognitive impairment, the gray matter patterns associated with dual-task gait performance differed by mild cognitive impairment subtype. These findings suggest that the brain substrates supporting dual-task gait performance in amnestic and non-amnestic subtypes are different, and consequently may respond differently to interventions, or require different interventions. PMID:27392792
Karaaslan, Fatih; Mermerkaya, Musa Uğur; Çıraklı, Alper; Karaoğlu, Sinan; Duygulu, Fuat
2016-01-01
Controversy remains regarding the optimal treatment method and postoperative rehabilitation of acute Achilles tendon ruptures. In this study, pedobarographic assessments of surgical and conservative treatments were compared. A prospective assessment was made of 16 patients (eight surgical, eight conservative) and eight healthy controls using a plantar pressure measurement system. Biomechanical gait parameters were obtained using the Footscan dynamic gait analysis system. Kruskal-Wallis and Mann-Whitney U-tests were used for the evaluation of data. Nineteen males and five females were assessed, with an average age of 42.0±11.9 years. Follow-up was completed in 16 patients. No statistically significant difference was determined between the two treatment groups with regard to the gait analysis, but a difference was observed with the control group (P<0.001). All patients were able to resume their prior activities after 6 months and regained normal ranges of motion, with a high rate of satisfaction. Most of the patients (75%) were able to return to their pre-injury level of activities. Satisfactory results were obtained through conservative treatment of acute ruptures of the Achilles tendon. No significant differences or complications were observed in the group managed conservatively versus the group treated surgically. Further studies including 3D gait analyses and tendon biomechanical research are required to further investigate this issue.
Local dynamic stability and gait variability during attentional tasks in young adults.
Magnani, Rina Márcia; Lehnen, Georgia Cristina; Rodrigues, Fábio Barbosa; de Sá E Souza, Gustavo Souto; de Oliveira Andrade, Adriano; Vieira, Marcus Fraga
2017-06-01
Cell phone use while walking may be a cognitive distraction and reduce visual and motor attention. Thus, the aim of this study was to verify the effects of attentional dual-tasks while using a cell phone in different conditions. Stability, regularity, and linear variability of trunk kinematics, and gait spatiotemporal parameters in young adults were measured. Twenty young subjects of both genders were asked to walk on a treadmill for 4min under the following conditions: (a) looking forward at a fixed target 2.5m away (walking); (b) talking on a cell phone with unilateral handling (talking); (c) texting messages on a cell phone with unilateral handling (texting); and (d) looking forward at the aforementioned target while listening to music without handling the phone (listening). Local dynamic stability measured in terms of the largest Lyapunov exponent decreased while handling a cell phone (talking and texting). Gait variability and regularity increased when talking on a cell phone, but no variable changed in the listening condition. Under all dual-task conditions, there were significant increases in stride width and its variability. We conclude that young adults who use a cell phone when walking adapt their gait pattern conservatively, which can be because of increased attentional demand during cell phone use. Copyright © 2017 Elsevier B.V. All rights reserved.
Manjeri Keloth, Sana; Arjunan, Sridhar P; Kumar, Dinesh
2017-07-01
This study has investigated the stride, swing, stance and double support intervals of gait for Parkinson's disease (PD) patients with different levels of severity. Self-similar properties of the gait signal were analyzed to investigate the changes in the gait pattern of the healthy and PD patients. To understand the self-similar property, detrended fluctuation analysis was performed. The analysis shows that the PD patients have less defined gait when compared to healthy. The study also shows that among the stance and swing phase of stride interval, the self-similarity is less for swing interval when compared to the stance interval of gait and decreases with the severity of gait. Also, PD patients show decreased self-similar patterns in double support interval of gait. This suggest that there are less rhythmic gait intervals and a sense of urgency to remain in support phase of gait by the PD patients.
Elsoe, Rasmus; Larsen, Peter
2017-07-01
Despite the high number of studies evaluating outcomes following tibial plateau fractures, the literature lacks studies including the objective assessment of gait pattern. The purpose of the present study was to evaluate asymmetry in gait patterns at 12 months after frame removal following ring fixation of a tibial plateau fracture. The study design was a prospective cohort study. The primary outcome measurement was the gait patterns 12 months after frame removal measured with a pressure-sensitive mat. The mat registers footprints and present gait speed, cadence, as well as temporal and spatial parameters of the gait cycle. Gait patterns were compared to a healthy reference population. Twenty-three patients were included with a mean age of 54.4 years (32-78 years). Patients presented with a shorter step-length of the injured leg compared to the non-injured leg (asymmetry of 11.3%). Analysis of single-support showed shorter support time of the injured leg compared to the non-injured leg (asymmetry of 8.7%). Moreover, analysis of swing-time showed increased swing-time of the injured leg (asymmetry of 8.9%). Compared to a healthy reference population, increased asymmetry in all gait patterns was observed. The association between asymmetry and health-related quality of life (HRQOL) showed moderate associations (single-support: R=0.50, P=0.03; step-length: R=0.43, P=0.07; swing-time: R=0.46, P=0.05). Compared to a healthy reference population, gait asymmetry is common 12 months after frame removal in patients treated with external ring fixation following a tibial plateau fracture of the tibia. Copyright © 2017 Elsevier Ltd. All rights reserved.
Longitudinal quasi-static stability predicts changes in dog gait on rough terrain
Reeve, Michelle A.; Haynes, G. Clark; Revzen, Shai; Koditschek, Daniel E.; Spence, Andrew J.
2017-01-01
ABSTRACT Legged animals utilize gait selection to move effectively and must recover from environmental perturbations. We show that on rough terrain, domestic dogs, Canis lupus familiaris, spend more time in longitudinal quasi-statically stable patterns of movement. Here, longitudinal refers to the rostro-caudal axis. We used an existing model in the literature to quantify the longitudinal quasi-static stability of gaits neighbouring the walk, and found that trot-like gaits are more stable. We thus hypothesized that when perturbed, the rate of return to a stable gait would depend on the direction of perturbation, such that perturbations towards less quasi-statically stable patterns of movement would be more rapid than those towards more stable patterns of movement. The net result of this would be greater time spent in longitudinally quasi-statically stable patterns of movement. Limb movement patterns in which diagonal limbs were more synchronized (those more like a trot) have higher longitudinal quasi-static stability. We therefore predicted that as dogs explored possible limb configurations on rough terrain at walking speeds, the walk would shift towards trot. We gathered experimental data quantifying dog gait when perturbed by rough terrain and confirmed this prediction using GPS and inertial sensors (n=6, P<0.05). By formulating gaits as trajectories on the n-torus we are able to make tractable the analysis of gait similarity. These methods can be applied in a comparative study of gait control which will inform the ultimate role of the constraints and costs impacting locomotion, and have applications in diagnostic procedures for gait abnormalities, and in the development of agile legged robots. PMID:28264903
Longitudinal quasi-static stability predicts changes in dog gait on rough terrain.
Wilshin, Simon; Reeve, Michelle A; Haynes, G Clark; Revzen, Shai; Koditschek, Daniel E; Spence, Andrew J
2017-05-15
Legged animals utilize gait selection to move effectively and must recover from environmental perturbations. We show that on rough terrain, domestic dogs, Canis lupus familiaris , spend more time in longitudinal quasi-statically stable patterns of movement. Here, longitudinal refers to the rostro-caudal axis. We used an existing model in the literature to quantify the longitudinal quasi-static stability of gaits neighbouring the walk, and found that trot-like gaits are more stable. We thus hypothesized that when perturbed, the rate of return to a stable gait would depend on the direction of perturbation, such that perturbations towards less quasi-statically stable patterns of movement would be more rapid than those towards more stable patterns of movement. The net result of this would be greater time spent in longitudinally quasi-statically stable patterns of movement. Limb movement patterns in which diagonal limbs were more synchronized (those more like a trot) have higher longitudinal quasi-static stability. We therefore predicted that as dogs explored possible limb configurations on rough terrain at walking speeds, the walk would shift towards trot. We gathered experimental data quantifying dog gait when perturbed by rough terrain and confirmed this prediction using GPS and inertial sensors ( n =6, P <0.05). By formulating gaits as trajectories on the n -torus we are able to make tractable the analysis of gait similarity. These methods can be applied in a comparative study of gait control which will inform the ultimate role of the constraints and costs impacting locomotion, and have applications in diagnostic procedures for gait abnormalities, and in the development of agile legged robots. © 2017. Published by The Company of Biologists Ltd.
Larsen, Peter; Laessoe, Uffe; Rasmussen, Sten; Graven-Nielsen, Thomas; Berre Eriksen, Christian; Elsoe, Rasmus
2017-01-01
Despite the high number of studies evaluating the outcomes following tibial shaft fractures, the literature lacks studies including objective assessment of patients' recovery regarding gait pattern. The purpose of the present study was to evaluate whether gait patterns at 6 and 12 months post-operatively following intramedullary nailing of a tibial shaft fracture are different compared with a healthy reference population. The study design was a prospective cohort study. The primary outcome measurement was the gait patterns at 6 and 12 months post-operatively measured with a 6-metre-long pressure-sensitive mat. The mat registers footprints and present gait speed, cadence as well as temporal and spatial parameters of the gait cycle. Gait patterns were compared to a healthy reference population. 49 patients were included with a mean age of 43.1 years (18-79 years). Forty-three patients completed the 12-month follow-up (88%). Gait speed and cadence were significantly increased between the 6- and 12-month follow-up (P<0.001). At 6-month follow-up, patients showed considerable asymmetry in the injured leg compared with the non-injured leg: single-support time 12.8% shorter, swing-time 12.8% longer, step-length 11.9% shorter, and rotation of the foot increased by 32.3%. At the 12-month follow-up, gait asymmetry become almost normalized compared to a healthy reference group. In patients treated by intramedullary nailing following a tibial shaft fracture, gait asymmetry accompanied with slower speed and cadence are common during the first 6 months and become normalized compared with a healthy reference population between 6 and 12 months post-operatively. Copyright © 2016 Elsevier B.V. All rights reserved.
Stepping strategies for regulating gait adaptability and stability.
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 (p<0.01), tended to increase step width (p=0.074), and decreased walking speed while maintaining similar step frequency compared to unconstrained walking. These adaptations 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.
Spontaneous Symmetry-Breaking in a Network Model for Quadruped Locomotion
NASA Astrophysics Data System (ADS)
Stewart, Ian
2017-12-01
Spontaneous symmetry-breaking proves a mechanism for pattern generation in legged locomotion of animals. The basic timing patterns of animal gaits are produced by a network of spinal neurons known as a Central Pattern Generator (CPG). Animal gaits are primarily characterized by phase differences between leg movements in a periodic gait cycle. Many different gaits occur, often having spatial or spatiotemporal symmetries. A natural way to explain gait patterns is to assume that the CPG is symmetric, and to classify the possible symmetry-breaking periodic motions. Pinto and Golubitsky have discussed a four-node model CPG network for biped gaits with ℤ2 × ℤ2 symmetry, classifying the possible periodic states that can arise. A more specific rate model with this structure has been analyzed in detail by Stewart. Here we extend these methods to quadruped gaits, using an eight-node network with ℤ4 × ℤ2 symmetry proposed by Golubitsky and coworkers. We formulate a rate model and calculate how the first steady or Hopf bifurcation depends on its parameters, which represent four connection strengths. The calculations involve a distinction between “real” gaits with one or two phase shifts (pronk, bound, pace, trot) and “complex” gaits with four phase shifts (forward and reverse walk, forward and reverse buck). The former correspond to real eigenvalues of the connection matrix, the latter to complex conjugate pairs. The partition of parameter space according to the first bifurcation, ignoring complex gaits, is described explicitly. The complex gaits introduce further complications, not yet fully understood. All eight gaits can occur as the first bifurcation from a fully synchronous equilibrium, for suitable parameters, and numerical simulations indicate that they can be asymptotically stable.
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.
Kloefkorn, Heidi E.; Pettengill, Travis R.; Turner, Sara M. F.; Streeter, Kristi A.; Gonzalez-Rothi, Elisa J.; Fuller, David D.; Allen, Kyle D.
2016-01-01
While rodent gait analysis can quantify the behavioral consequences of disease, significant methodological differences exist between analysis platforms and little validation has been performed to understand or mitigate these sources of variance. By providing the algorithms used to quantify gait, open-source gait analysis software can be validated and used to explore methodological differences. Our group is introducing, for the first time, a fully-automated, open-source method for the characterization of rodent spatiotemporal gait patterns, termed Automated Gait Analysis Through Hues and Areas (AGATHA). This study describes how AGATHA identifies gait events, validates AGATHA relative to manual digitization methods, and utilizes AGATHA to detect gait compensations in orthopaedic and spinal cord injury models. To validate AGATHA against manual digitization, results from videos of rodent gait, recorded at 1000 frames per second (fps), were compared. To assess one common source of variance (the effects of video frame rate), these 1000 fps videos were re-sampled to mimic several lower fps and compared again. While spatial variables were indistinguishable between AGATHA and manual digitization, low video frame rates resulted in temporal errors for both methods. At frame rates over 125 fps, AGATHA achieved a comparable accuracy and precision to manual digitization for all gait variables. Moreover, AGATHA detected unique gait changes in each injury model. These data demonstrate AGATHA is an accurate and precise platform for the analysis of rodent spatiotemporal gait patterns. PMID:27554674
Kloefkorn, Heidi E; Pettengill, Travis R; Turner, Sara M F; Streeter, Kristi A; Gonzalez-Rothi, Elisa J; Fuller, David D; Allen, Kyle D
2017-03-01
While rodent gait analysis can quantify the behavioral consequences of disease, significant methodological differences exist between analysis platforms and little validation has been performed to understand or mitigate these sources of variance. By providing the algorithms used to quantify gait, open-source gait analysis software can be validated and used to explore methodological differences. Our group is introducing, for the first time, a fully-automated, open-source method for the characterization of rodent spatiotemporal gait patterns, termed Automated Gait Analysis Through Hues and Areas (AGATHA). This study describes how AGATHA identifies gait events, validates AGATHA relative to manual digitization methods, and utilizes AGATHA to detect gait compensations in orthopaedic and spinal cord injury models. To validate AGATHA against manual digitization, results from videos of rodent gait, recorded at 1000 frames per second (fps), were compared. To assess one common source of variance (the effects of video frame rate), these 1000 fps videos were re-sampled to mimic several lower fps and compared again. While spatial variables were indistinguishable between AGATHA and manual digitization, low video frame rates resulted in temporal errors for both methods. At frame rates over 125 fps, AGATHA achieved a comparable accuracy and precision to manual digitization for all gait variables. Moreover, AGATHA detected unique gait changes in each injury model. These data demonstrate AGATHA is an accurate and precise platform for the analysis of rodent spatiotemporal gait patterns.
Zhang, Jian; Lockhart, Thurmon E.; Soangra, Rahul
2013-01-01
Fatigue in lower extremity musculature is associated with decline in postural stability, motor performance and alters normal walking patterns in human subjects. Automated recognition of lower extremity muscle fatigue condition may be advantageous in early detection of fall and injury risks. Supervised machine learning methods such as Support Vector Machines (SVM) have been previously used for classifying healthy and pathological gait patterns and also for separating old and young gait patterns. In this study we explore the classification potential of SVM in recognition of gait patterns utilizing an inertial measurement unit associated with lower extremity muscular fatigue. Both kinematic and kinetic gait patterns of 17 participants (29±11 years) were recorded and analyzed in normal and fatigued state of walking. Lower extremities were fatigued by performance of a squatting exercise until the participants reached 60% of their baseline maximal voluntary exertion level. Feature selection methods were used to classify fatigue and no-fatigue conditions based on temporal and frequency information of the signals. Additionally, influences of three different kernel schemes (i.e., linear, polynomial, and radial basis function) were investigated for SVM classification. The results indicated that lower extremity muscle fatigue condition influenced gait and loading responses. In terms of the SVM classification results, an accuracy of 96% was reached in distinguishing the two gait patterns (fatigue and no-fatigue) within the same subject using the kinematic, time and frequency domain features. It is also found that linear kernel and RBF kernel were equally good to identify intra-individual fatigue characteristics. These results suggest that intra-subject fatigue classification using gait patterns from an inertial sensor holds considerable potential in identifying “at-risk” gait due to muscle fatigue. PMID:24081829
Symmetry in locomotor central pattern generators and animal gaits
NASA Astrophysics Data System (ADS)
Golubitsky, Martin; Stewart, Ian; Buono, Pietro-Luciano; Collins, J. J.
1999-10-01
Animal locomotion is controlled, in part, by a central pattern generator (CPG), which is an intraspinal network of neurons capable of generating a rhythmic output. The spatio-temporal symmetries of the quadrupedal gaits walk, trot and pace lead to plausible assumptions about the symmetries of locomotor CPGs. These assumptions imply that the CPG of a quadruped should consist of eight nominally identical subcircuits, arranged in an essentially unique matter. Here we apply analogous arguments to myriapod CPGs. Analyses based on symmetry applied to these networks lead to testable predictions, including a distinction between primary and secondary gaits, the existence of a new primary gait called `jump', and the occurrence of half-integer wave numbers in myriapod gaits. For bipeds, our analysis also predicts two gaits with the out-of-phase symmetry of the walk and two gaits with the in-phase symmetry of the hop. We present data that support each of these predictions. This work suggests that symmetry can be used to infer a plausible class of CPG network architectures from observed patterns of animal gaits.
Morphological computation of multi-gaited robot locomotion based on free vibration.
Reis, Murat; Yu, Xiaoxiang; Maheshwari, Nandan; Iida, Fumiya
2013-01-01
In recent years, there has been increasing interest in the study of gait patterns in both animals and robots, because it allows us to systematically investigate the underlying mechanisms of energetics, dexterity, and autonomy of adaptive systems. In particular, for morphological computation research, the control of dynamic legged robots and their gait transitions provides additional insights into the guiding principles from a synthetic viewpoint for the emergence of sensible self-organizing behaviors in more-degrees-of-freedom systems. This article presents a novel approach to the study of gait patterns, which makes use of the intrinsic mechanical dynamics of robotic systems. Each of the robots consists of a U-shaped elastic beam and exploits free vibration to generate different locomotion patterns. We developed a simplified physics model of these robots, and through experiments in simulation and real-world robotic platforms, we show three distinctive mechanisms for generating different gait patterns in these robots.
2013-01-01
Background Robot-assisted gait training and treadmill training can complement conventional physical therapy in children with neuro-orthopedic movement disorders. The aim of this study was to investigate surface electromyography (sEMG) activity patterns during robot-assisted gait training (with and without motivating instructions from a therapist) and unassisted treadmill walking and to compare these with physiological sEMG patterns. Methods Nine children with motor impairments and eight healthy children walked in various conditions: (a) on a treadmill in the driven gait orthosis Lokomat®, (b) same condition, with additional motivational instructions from a therapist, and (c) on the treadmill without assistance. sEMG recordings were made of the tibialis anterior, gastrocnemius lateralis, vastus medialis, and biceps femoris muscles. Differences in sEMG amplitudes between the three conditions were analyzed for the duration of stance and swing phase (for each group and muscle separately) using non-parametric tests. Spearman’s correlation coefficients illustrated similarity of muscle activation patterns between conditions, between groups, and with published reference trajectories. Results The relative duration of stance and swing phase differed between patients and controls, and between driven gait orthosis conditions and treadmill walking. While sEMG amplitudes were higher when being encouraged by a therapist compared to robot-assisted gait training without instructions (0.008 ≤ p-value ≤ 0.015), muscle activation patterns were highly comparable (0.648 ≤ Spearman correlation coefficients ≤ 0.969). In general, comparisons of the sEMG patterns with published reference data of over-ground walking revealed that walking in the driven gait orthosis could induce more physiological muscle activation patterns compared to unsupported treadmill walking. Conclusions Our results suggest that robotic-assisted gait training with therapeutic encouragement could appropriately increase muscle activity. Robotic-assisted gait training in general could induce physiological muscle activation patterns, which might indicate that this training exploits restorative rather than compensatory mechanisms. PMID:23867005
Muscle strength and kinetic gait pattern in children with bilateral spastic CP.
Eek, Meta Nyström; Tranberg, Roy; Beckung, Eva
2011-03-01
Cerebral palsy is often associated with an abnormal gait pattern. This study put focus on relation between muscle strength and kinetic gait pattern in children with bilateral spastic cerebral palsy and compares them with a reference group. In total 20 children with CP and 20 typically developing children participated. They were all assessed with measurement of muscle strength in eight muscle groups in the legs and a 3-dimensional gait analysis including force data. It was found that children with CP were not only significantly weaker in all muscle groups but also walked with slower velocity and shorter stride length when compared with the reference group. Gait moments differed at the ankle level with significantly lower moments in children with CP. Gait moments were closer to the maximal muscle strength in the group of children with CP. Furthermore a correlation between plantarflexing gait moment and muscle strength was observed in six of the eight muscle groups in children with CP, a relation not found in the reference group. A similar pattern was seen between muscle strength and generating ankle power with a rho=0.582-0.766. The results of this study state the importance of the relationship of the overall muscle strength pattern in the lower extremity, not only the plantarflexors. Copyright © 2010 Elsevier B.V. All rights reserved.
Street, Brian D; Gage, William
2013-04-01
The external knee adduction moment is an accurate estimation of the load distribution of the knee and is a valid predictor for the presence, severity and progression rate of medial compartment knee osteoarthritis. Gait modification strategies have been shown to be an effective means of reducing the external adduction moment. The purpose of this study was to test narrow gait as a mechanism to reduce the external adduction moment and investigate if limb dominance affects this pattern. Fifteen healthy male participants (mean age: 23.8 (SD=3.1) years, mean height: 1.8 (SD=0.1) m, and mean body mass: 82.9 (SD=16.1 kg) took part in this study. Five walking trials were performed for each of the three different gait conditions: normal gait, toe-out gait, and narrow gait. Adoption of the narrow gait strategy significantly reduced the early stance phase external knee adduction moment compared to normal and toe-out gait (p<.002). However, it was observed that this reduction only occurred in the non-dominant limb. Gait modification can reduce the external knee adduction moment. However, asymmetrical patterns between the dominant and non-dominant limbs, specifically during gait modification, may attenuate the effectiveness of this intervention. The mechanism of limb dominance and the specific roles of each limb during gait may account for an asymmetrical pattern in the moment arm and center of mass displacement during stance. This new insight into how limb-dominance effects gait modification strategies will be useful in the clinical setting when identifying appropriate patients, when indicating a gait modification strategy and in future research methodology. Copyright © 2013 Elsevier B.V. All rights reserved.
Modification of hemiplegic compensatory gait pattern by symmetry-based motion controller of HAL.
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.
Yoon, Jiyeon; Park, Jinse; Park, Kunbo; Jo, Geunyeol; Kim, Haeyu; Jang, Wooyoung; Kim, Ji Sun; Youn, Jinyoung; Oh, Eung Seok; Kim, Hee-Tae; Youm, Chang Hong
2016-01-01
Recently, arm facilitation has been interested in gait rehabilitation. However, there have been few studies concerning arm facilitation in patients with Parkinson's disease (PD). The aim of our study was to investigate the effect of increasing arm weights on gait pattern in patients with PD. Twenty-seven patients with PD were enrolled, and they underwent gait analysis using a three-dimensional motion capture system. Sandbags were applied to the distal forearms in all participants. We compared gait parameters including arm swing, pelvic motion, spatiotemporal data, and relative rotational angle between the weighted and unweighted gaits. The total arm-swing amplitude and pelvic rotation were significantly higher when walking with additional arm weights than without arm weights. Cadence, walking speed, stride length, and swing phase were significantly higher, whereas stride time, double-support time, and stance phase were significantly lower, when walking with additional arm weights than without arm weights. We conclude that adding weights to the arm during walking may facilitate arm and pelvic movements, which results in changes to gait patterns. The therapeutic use of additional arm weights could be considered for gait rehabilitation in PD to improve gait impairment. Arm-swing facilitation using weight load improved gait in Parkinson's disease. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.
Vision-based gait impairment analysis for aided diagnosis.
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.
Computer aided analysis of gait patterns in patients with acute anterior cruciate ligament injury.
Christian, Josef; Kröll, Josef; Strutzenberger, Gerda; Alexander, Nathalie; Ofner, Michael; Schwameder, Hermann
2016-03-01
Gait analysis is a useful tool to evaluate the functional status of patients with anterior cruciate ligament injury. Pattern recognition methods can be used to automatically assess walking patterns and objectively support clinical decisions. This study aimed to test a pattern recognition system for analyzing kinematic gait patterns of recently anterior cruciate ligament injured patients and for evaluating the effects of a therapeutic treatment. Gait kinematics of seven male patients with an acute unilateral anterior cruciate ligament rupture and seven healthy males were recorded. A support vector machine was trained to distinguish the groups. Principal component analysis and recursive feature elimination were used to extract features from 3D marker trajectories. A Classifier Oriented Gait Score was defined as a measure of gait quality. Visualizations were used to allow functional interpretations of characteristic group differences. The injured group was evaluated by the system after a therapeutic treatment. The results were compared against a clinical rating of the patients' gait. Cross validation yielded 100% accuracy. After the treatment the score improved significantly (P<0.01) as well as the clinical rating (P<0.05). The visualizations revealed characteristic kinematic features, which differentiated between the groups. The results show that gait alterations in the early phase after anterior cruciate ligament injury can be detected automatically. The results of the automatic analysis are comparable with the clinical rating and support the validity of the system. The visualizations allow interpretations on discriminatory features and can facilitate the integration of the results into the diagnostic process. Copyright © 2016 Elsevier Ltd. All rights reserved.
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.
ERIC Educational Resources Information Center
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…
Kinematic gait patterns in healthy runners: A hierarchical cluster analysis.
Phinyomark, Angkoon; Osis, Sean; Hettinga, Blayne A; Ferber, Reed
2015-11-05
Previous studies have demonstrated distinct clusters of gait patterns in both healthy and pathological groups, suggesting that different movement strategies may be represented. However, these studies have used discrete time point variables and usually focused on only one specific joint and plane of motion. Therefore, the first purpose of this study was to determine if running gait patterns for healthy subjects could be classified into homogeneous subgroups using three-dimensional kinematic data from the ankle, knee, and hip joints. The second purpose was to identify differences in joint kinematics between these groups. The third purpose was to investigate the practical implications of clustering healthy subjects by comparing these kinematics with runners experiencing patellofemoral pain (PFP). A principal component analysis (PCA) was used to reduce the dimensionality of the entire gait waveform data and then a hierarchical cluster analysis (HCA) determined group sets of similar gait patterns and homogeneous clusters. The results show two distinct running gait patterns were found with the main between-group differences occurring in frontal and sagittal plane knee angles (P<0.001), independent of age, height, weight, and running speed. When these two groups were compared to PFP runners, one cluster exhibited greater while the other exhibited reduced peak knee abduction angles (P<0.05). The variability observed in running patterns across this sample could be the result of different gait strategies. These results suggest care must be taken when selecting samples of subjects in order to investigate the pathomechanics of injured runners. Copyright © 2015 Elsevier Ltd. All rights reserved.
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.
Linking clinical measurements and kinematic gait patterns of toe-walking using fuzzy decision trees.
Armand, Stéphane; Watelain, Eric; Roux, Emmanuel; Mercier, Moïse; Lepoutre, François-Xavier
2007-03-01
Toe-walking is one of the most prevalent gait deviations and has been linked to many diseases. Three major ankle kinematic patterns have been identified in toe-walkers, but the relationships between the causes of toe-walking and these patterns remain unknown. This study aims to identify these relationships. Clearly, such knowledge would increase our understanding of this gait deviation, and could help clinicians plan treatment. The large quantity of data provided by gait analysis often makes interpretation a difficult task. Artificial intelligence techniques were used in this study to facilitate interpretation as well as to decrease subjective interpretation. Of the 716 limbs evaluated, 240 showed signs of toe-walking and met inclusion criteria. The ankle kinematic pattern of the evaluated limbs during gait was assigned to one of three toe-walking pattern groups to build the training data set. Toe-walker clinical measurements (range of movement, muscle spasticity and muscle strength) were coded in fuzzy modalities, and fuzzy decision trees were induced to create intelligible rules allowing toe-walkers to be assigned to one of the three groups. A stratified 10-fold cross validation situated the classification accuracy at 81%. Twelve rules depicting the causes of toe-walking were selected, discussed and characterized using kinematic, kinetic and EMG charts. This study proposes an original approach to linking the possible causes of toe-walking with gait patterns.
Spastic diplegia in children with HIV encephalopathy: first description of gait and physical status.
Langerak, Nelleke G; du Toit, Jacques; Burger, Marlette; Cotton, Mark F; Springer, Priscilla E; Laughton, Barbara
2014-07-01
The aim of this study was to explore the physical status and gait patterns of children with spastic diplegia secondary to human immunodeficiency virus encephalopathy (HIVE). A cross-sectional study was conducted on children diagnosed with HIVE and spastic diplegia. Sociodemographic and clinical background information was obtained, followed by three-dimensional gait analysis (3DGA) and a physical examination including assessments of muscle tone, strength, motor control, contractures, and bony deformities of the lower extremities. Fourteen children (eight males, six females; mean age 5 y 8 mo [SD 9 mo], range 4 y 4 mo-6 y 10 mo) were studied. The cohort was divided into two groups based on distinctive gait patterns. Nine participants in group I showed only limited abnormalities. Group II displayed a more pathological gait pattern including stiff knee and equinus ankle abnormalities. Results of 3DGA, as with the physical examination outcomes, showed increased impairments from proximal to distal (except for hip extension). This study provides a first description of distinctive gait patterns and related physical characteristics of children with HIVE and spastic diplegia. Further research is necessary. © 2013 Mac Keith Press.
Quadrupedal gaits in hexapod animals - inter-leg coordination in free-walking adult stick insects.
Grabowska, Martyna; Godlewska, Elzbieta; Schmidt, Joachim; Daun-Gruhn, Silvia
2012-12-15
The analysis of inter-leg coordination in insect walking is generally a study of six-legged locomotion. For decades, the stick insect Carausius morosus has been instrumental for unravelling the rules and mechanisms that control leg coordination in hexapeds. We analysed inter-leg coordination in C. morosus that freely walked on straight paths on plane surfaces with different slopes. Consecutive 1.7 s sections were assigned inter-leg coordination patterns (which we call gaits) based on footfall patterns. Regular gaits, i.e. wave, tetrapod or tripod gaits, occurred in different proportions depending on surface slopes. Tetrapod gaits were observed most frequently, wave gaits only occurred on 90 deg inclining slopes and tripod gaits occurred most often on 15 deg declining slopes, i.e. in 40% of the sections. Depending on the slope, 36-66% of the sections were assigned irregular gaits. Irregular gaits were mostly due to multiple stepping by the front legs, which is perhaps probing behaviour, not phase coupled to the middle legs' cycles. In irregular gaits, middle leg and hindleg coordination was regular, related to quadrupedal walk and wave gaits. Apparently, front legs uncouple from and couple to the walking system without compromising middle leg and hindleg coordination. In front leg amputees, the remaining legs were strictly coordinated. In hindleg and middle leg amputees, the front legs continued multiple stepping. The coordination of middle leg amputees was maladapted, with front legs and hindlegs performing multiple steps or ipsilateral legs being in simultaneous swing. Thus, afferent information from middle legs might be necessary for a regular hindleg stepping pattern.
Quantifying gait patterns in Parkinson's disease
NASA Astrophysics Data System (ADS)
Romero, Mónica; Atehortúa, Angélica; Romero, Eduardo
2017-11-01
Parkinson's disease (PD) is constituted by a set of motor symptoms, namely tremor, rigidity, and bradykinesia, which are usually described but not quantified. This work proposes an objective characterization of PD gait patterns by approximating the single stance phase a single grounded pendulum. This model estimates the force generated by the gait during the single support from gait data. This force describes the motion pattern for different stages of the disease. The model was validated using recorded videos of 8 young control subjects, 10 old control subjects and 10 subjects with Parkinson's disease in different stages. The estimated force showed differences among stages of Parkinson disease, observing a decrease of the estimated force for the advanced stages of this illness.
Probabilistic Gait Classification in Children with Cerebral Palsy: A Bayesian Approach
ERIC Educational Resources Information Center
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,…
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.
Neuromorphic walking gait control.
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.
Gait Patterns in Hemiplegic Children with Cerebral Palsy: Comparison of Right and Left Hemiplegia
ERIC Educational Resources Information Center
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…
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.
Quadrupedal locomotor simulation: producing more realistic gaits using dual-objective optimization
Hirasaki, Eishi
2018-01-01
In evolutionary biomechanics it is often considered that gaits should evolve to minimize the energetic cost of travelling a given distance. In gait simulation this goal often leads to convincing gait generation. However, as the musculoskeletal models used get increasingly sophisticated, it becomes apparent that such a single goal can lead to extremely unrealistic gait patterns. In this paper, we explore the effects of requiring adequate lateral stability and show how this increases both energetic cost and the realism of the generated walking gait in a high biofidelity chimpanzee musculoskeletal model. We also explore the effects of changing the footfall sequences in the simulation so it mimics both the diagonal sequence walking gaits that primates typically use and also the lateral sequence walking gaits that are much more widespread among mammals. It is apparent that adding a lateral stability criterion has an important effect on the footfall phase relationship, suggesting that lateral stability may be one of the key drivers behind the observed footfall sequences in quadrupedal gaits. The observation that single optimization goals are no longer adequate for generating gait in current models has important implications for the use of biomimetic virtual robots to predict the locomotor patterns in fossil animals. PMID:29657790
Automated classification of neurological disorders of gait using spatio-temporal gait parameters.
Pradhan, Cauchy; Wuehr, Max; Akrami, Farhoud; Neuhaeusser, Maximilian; Huth, Sabrina; Brandt, Thomas; Jahn, Klaus; Schniepp, Roman
2015-04-01
Automated pattern recognition systems have been used for accurate identification of neurological conditions as well as the evaluation of the treatment outcomes. This study aims to determine the accuracy of diagnoses of (oto-)neurological gait disorders using different types of automated pattern recognition techniques. Clinically confirmed cases of phobic postural vertigo (N = 30), cerebellar ataxia (N = 30), progressive supranuclear palsy (N = 30), bilateral vestibulopathy (N = 30), as well as healthy subjects (N = 30) were recruited for the study. 8 measurements with 136 variables using a GAITRite(®) sensor carpet were obtained from each subject. Subjects were randomly divided into two groups (training cases and validation cases). Sensitivity and specificity of k-nearest neighbor (KNN), naive-bayes classifier (NB), artificial neural network (ANN), and support vector machine (SVM) in classifying the validation cases were calculated. ANN and SVM had the highest overall sensitivity with 90.6% and 92.0% respectively, followed by NB (76.0%) and KNN (73.3%). SVM and ANN showed high false negative rates for bilateral vestibulopathy cases (20.0% and 26.0%); while KNN and NB had high false negative rates for progressive supranuclear palsy cases (76.7% and 40.0%). Automated pattern recognition systems are able to identify pathological gait patterns and establish clinical diagnosis with good accuracy. SVM and ANN in particular differentiate gait patterns of several distinct oto-neurological disorders of gait with high sensitivity and specificity compared to KNN and NB. Both SVM and ANN appear to be a reliable diagnostic and management tool for disorders of gait. Copyright © 2015 Elsevier Ltd. All rights reserved.
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 swing, can contribute largely to an increased plantarflexion and knee extension during the swing phase and consequently to hampered toe clearance. Our results support the idea that hyperexcitability of length and velocity feedback pathways, especially in combination with altered reflex modulation patterns, can contribute to deviations in hemiparetic gait. Surprisingly, our results showed only subtle temporal differences between length and velocity feedback. Therefore, we cannot attribute the effects seen in kinematics to one specific type of feedback.
Ferrante, Simona; Ambrosini, Emilia; Ravelli, Paola; Guanziroli, Eleonora; Molteni, Franco; Ferrigno, Giancarlo; Pedrocchi, Alessandra
2011-08-24
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. 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. 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. The results demonstrated that the treatment is feasible and it might be effective in translating progresses from pedaling to locomotion. If these results are confirmed on a larger and controlled scale, the intervention, thanks to its safety and low price, could have a significant impact as a home- rehabilitation treatment for chronic stroke patients.
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 < 0.05). Kinematic data demonstrated that anterior tilt of the pelvis and hip flexion during a gait cycle was significantly ameliorated after rhythmic auditory stimulation (P < 0.05). Gait deviation index also showed modest improvement in cerebral palsy patients treated with rhythmic auditory stimulation (P < 0.05). However, neurodevelopmental treatment showed that internal and external rotations of hip joints were significantly improved, whereas rhythmic auditory stimulation showed aggravated maximal internal rotation in the transverse plane (P < 0.05). Gait training with rhythmic auditory stimulation or neurodevelopmental treatment elicited differential effects on gait patterns in adults with cerebral palsy.
Wang, Wei; Ackland, David C; McClelland, Jodie A; Webster, Kate E; Halgamuge, Saman
2018-01-01
Quantitative gait analysis is an important tool in objective assessment and management of total knee arthroplasty (TKA) patients. Studies evaluating gait patterns in TKA patients have tended to focus on discrete data such as spatiotemporal information, joint range of motion and peak values of kinematics and kinetics, or consider selected principal components of gait waveforms for analysis. These strategies may not have the capacity to capture small variations in gait patterns associated with each joint across an entire gait cycle, and may ultimately limit the accuracy of gait classification. The aim of this study was to develop an automatic feature extraction method to analyse patterns from high-dimensional autocorrelated gait waveforms. A general linear feature extraction framework was proposed and a hierarchical partial least squares method derived for discriminant analysis of multiple gait waveforms. The effectiveness of this strategy was verified using a dataset of joint angle and ground reaction force waveforms from 43 patients after TKA surgery and 31 healthy control subjects. Compared with principal component analysis and partial least squares methods, the hierarchical partial least squares method achieved generally better classification performance on all possible combinations of waveforms, with the highest classification accuracy . The novel hierarchical partial least squares method proposed is capable of capturing virtually all significant differences between TKA patients and the controls, and provides new insights into data visualization. The proposed framework presents a foundation for more rigorous classification of gait, and may ultimately be used to evaluate the effects of interventions such as surgery and rehabilitation.
Entrainment to a real time fractal visual stimulus modulates fractal gait dynamics.
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.
Stepping over obstacles: gait patterns of healthy young and old adults.
Chen, H C; Ashton-Miller, J A; Alexander, N B; Schultz, A B
1991-11-01
Falls associated with tripping over an obstacle can be devastating to elderly individuals, yet little is known about the strategies used for stepping over obstacles by either old or young adults. The gait of gender-matched groups of 24 young and 24 old healthy adults (mean ages 22 and 71 years) was studied during a 4 m approach to and while stepping over obstacles of 0, 25, 51, or 152 mm height and in level obstacle-free walking. Optoelectronic cameras and recorders were used to record approach and obstacle crossing speeds as well as bilateral lower extremity kinematic parameters that described foot placement and movement trajectories relative to the obstacle. The results showed that age had no effect on minimum swing foot clearance (FC) over an obstacle. For the 25 mm obstacle, mean FC was 64 mm, or approximately three times that used in level gait; FC increased nonlinearly with obstacle height for all subjects. Although no age differences were found in obstacle-free gait, old adults exhibited a significantly more conservative strategy when crossing obstacles, with slower crossing speed, shorter step length, and shorter obstacle-heel strike distance. In addition, the old adults crossed the obstacle so that it was 10% further forward in their obstacle-crossing step. Although all subjects successfully avoided the riskiest form of obstacle contact, tripping, 4/24 healthy old adults stepped on an obstacle, demonstrating an increased risk for obstacle contact with age.
Effect of Rhythmic Auditory Stimulation on Hemiplegic Gait Patterns.
Shin, Yoon-Kyum; Chong, Hyun Ju; Kim, Soo Ji; Cho, Sung-Rae
2015-11-01
The purpose of our study was to investigate the effect of gait training with rhythmic auditory stimulation (RAS) on both kinematic and temporospatial gait patterns in patients with hemiplegia. Eighteen hemiplegic patients diagnosed with either cerebral palsy or stroke participated in this study. All participants underwent the 4-week gait training with RAS. The treatment was performed for 30 minutes per each session, three sessions per week. RAS was provided with rhythmic beats using a chord progression on a keyboard. Kinematic and temporospatial data were collected and analyzed using a three-dimensional motion analysis system. Gait training with RAS significantly improved both proximal and distal joint kinematic patterns in hip adduction, knee flexion, and ankle plantar flexion, enhancing the gait deviation index (GDI) as well as ameliorating temporal asymmetry of the stance and swing phases in patients with hemiplegia. Stroke patients with previous walking experience demonstrated significant kinematic improvement in knee flexion in mid-swing and ankle dorsiflexion in terminal stance. Among stroke patients, subacute patients showed a significantly increased GDI score compared with chronic patients. In addition, household ambulators showed a significant effect on reducing anterior tilt of the pelvis with an enhanced GDI score, while community ambulators significantly increased knee flexion in mid-swing phase and ankle dorsiflexion in terminal stance phase. Gait training with RAS has beneficial effects on both kinematic and temporospatial patterns in patients with hemiplegia, providing not only clinical implications of locomotor rehabilitation with goal-oriented external feedback using RAS but also differential effects according to ambulatory function.
Adaptive changes in spatiotemporal gait characteristics in women during pregnancy.
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.
Xu, Benlei; Yan, Tiebin; Yang, Yuanle; Ou, Ruiqing; Huang, Shuping
2016-01-01
Functional electrical stimulation is a widely used technique for rehabilitation. To assess the efficacy of walking-pattern-based four-channel functional electric stimulation and its influence on the gait features of stroke patients with hemiplegia. A total of 21 stroke patients with hemiplegia were enrolled into the study. The walking gaits of patients were investigated before, during and after walking-pattern-based FES treatment using the gait analysis system. The changes of gait indexes were comparatively analyzed. After walking-pattern-based FES therapy, the pace, stride rate, gait cycle, and step length of stroke patients with hemiplegia were 50.19 ± 14.45 cm/s, 36.85 ± 5.85 time/min, 1.6643 ± 0.2626 sec, 80.3333 ± 15.1438 cm, respectively. The motion range of hip and knee joint were 47.5238 ± 10.7453, 56.7619 ± 14.5255, respectively. We found these indexes were significantly improved compared with those before FES treatment (P < 0.05). The single swing rate (injured extremity/uninjured extremity) after FES treatment was 1.5589 ± 0.4550. The statistical results showed that the gait cycle, pace, stride rat, and single swing rate (injured extremity/uninjured extremity) were significantly improved after FES treatment (P < 0.05). Our results demonstrate that walking-paradigm based FES we developed is effective for treating stroke patients during rehabilitation.
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 <0.01). The pattern and amount of activation of relevant weight-bearing muscles was comparable with an even larger activation of the M. biceps femoris on the gait trainer (p <0.01). The tibialis anterior muscle of the nonaffected side, however, was less activated during swing (p <0.01). Two therapists assisted walking on the treadmill while only one therapist was necessary to help with weight shifting on the new device. The newly developed 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.
Identity Recognition Algorithm Using Improved Gabor Feature Selection of Gait Energy Image
NASA Astrophysics Data System (ADS)
Chao, LIANG; Ling-yao, JIA; Dong-cheng, SHI
2017-01-01
This paper describes an effective gait recognition approach based on Gabor features of gait energy image. In this paper, the kernel Fisher analysis combined with kernel matrix is proposed to select dominant features. The nearest neighbor classifier based on whitened cosine distance is used to discriminate different gait patterns. The approach proposed is tested on the CASIA and USF gait databases. The results show that our approach outperforms other state of gait recognition approaches in terms of recognition accuracy and robustness.
Model Predictive Control-based gait pattern generation for wearable exoskeletons.
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
Optimality Principles for Model-Based Prediction of Human Gait
Ackermann, Marko; van den Bogert, Antonie J.
2010-01-01
Although humans have a large repertoire of potential movements, gait patterns tend to be stereotypical and appear to be selected according to optimality principles such as minimal energy. When applied to dynamic musculoskeletal models such optimality principles might be used to predict how a patient’s gait adapts to mechanical interventions such as prosthetic devices or surgery. In this paper we study the effects of different performance criteria on predicted gait patterns using a 2D musculoskeletal model. The associated optimal control problem for a family of different cost functions was solved utilizing the direct collocation method. It was found that fatigue-like cost functions produced realistic gait, with stance phase knee flexion, as opposed to energy-related cost functions which avoided knee flexion during the stance phase. We conclude that fatigue minimization may be one of the primary optimality principles governing human gait. PMID:20074736
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.
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
An Ambulatory Method of Identifying Anterior Cruciate Ligament Reconstructed Gait Patterns
Patterson, Matthew R.; Delahunt, Eamonn; Sweeney, Kevin T.; Caulfield, Brian
2014-01-01
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. PMID:24451464
Metabolic cost and mechanics of walking in women with fibromyalgia syndrome.
MacPhee, Renée S; McFall, Kristen; Perry, Stephen D; Tiidus, Peter M
2013-10-18
Fibromyalgia syndrome (FS) is characterized by the presence of widespread pain, fatigue, muscle weakness and reduced work capacity. Previous research has demonstrated that women with fibromyalgia have altered walking (gait) patterns, which may be a consequence of muscular pain. This altered gait is characterized by greater reliance on hip flexors rather than ankle plantar flexors and resembles gait patterns seen in normal individuals walking at higher speeds, suggesting that gait of individuals with fibromyalgia may be less efficient.This study compared rates of energy expenditure of 6 females with FS relative to 6 normal, age and weight matched controls, at various walking speeds on a motorized treadmill. Metabolic measurements including V02 (ml/kg/min), respirations, heart rate and calculated energy expenditures as well as the Borg Scale of Perceived Exertion scale ratings were determined at baseline and for 10 min while walking at each of 2, 4 and 5 km/hour on 1% grade. Kinematic recordings of limb and body movements while treadmill walking and separate measurements of ground reaction forces while walking over ground were also determined. In addition, all subjects completed the RAND 36-Item Health Survey (1.0). Gait analysis results were similar to previous reports of altered gait patterns in FS females. Despite noticeable differences in gait patterns, no significant differences (p > 0.05) existed between the FS and control subjects on any metabolic measures at any walking speed. Total number of steps taken was also similar between groups. Ratings on the Borg Scale of Perceived Exertion, the RAND and self-reported levels of pain indicated significantly greater (p < 0.05) perceived effort and pain in FS subjects relative to control subjects during walking and daily activities. The altered gait patterns and greater perceptions of effort and pain did not significantly increase the metabolic costs of walking in women with FS and hence, increased sensations of fatigue in FS women may not be related to alteration in metabolic cost of ambulation.
Metabolic cost and mechanics of walking in women with fibromyalgia syndrome
2013-01-01
Background Fibromyalgia syndrome (FS) is characterized by the presence of widespread pain, fatigue, muscle weakness and reduced work capacity. Previous research has demonstrated that women with fibromyalgia have altered walking (gait) patterns, which may be a consequence of muscular pain. This altered gait is characterized by greater reliance on hip flexors rather than ankle plantar flexors and resembles gait patterns seen in normal individuals walking at higher speeds, suggesting that gait of individuals with fibromyalgia may be less efficient. This study compared rates of energy expenditure of 6 females with FS relative to 6 normal, age and weight matched controls, at various walking speeds on a motorized treadmill. Metabolic measurements including V02 (ml/kg/min), respirations, heart rate and calculated energy expenditures as well as the Borg Scale of Perceived Exertion scale ratings were determined at baseline and for 10 min while walking at each of 2, 4 and 5 km/hour on 1% grade. Kinematic recordings of limb and body movements while treadmill walking and separate measurements of ground reaction forces while walking over ground were also determined. In addition, all subjects completed the RAND 36-Item Health Survey (1.0). Findings Gait analysis results were similar to previous reports of altered gait patterns in FS females. Despite noticeable differences in gait patterns, no significant differences (p > 0.05) existed between the FS and control subjects on any metabolic measures at any walking speed. Total number of steps taken was also similar between groups. Ratings on the Borg Scale of Perceived Exertion, the RAND and self-reported levels of pain indicated significantly greater (p < 0.05) perceived effort and pain in FS subjects relative to control subjects during walking and daily activities. Conclusions The altered gait patterns and greater perceptions of effort and pain did not significantly increase the metabolic costs of walking in women with FS and hence, increased sensations of fatigue in FS women may not be related to alteration in metabolic cost of ambulation. PMID:24139565
Sjöström, Henrik; Allum, John H J; Carpenter, Mark G; Adkin, Allan L; Honegger, Flurin; Ettlin, Thierry
2003-08-01
Trunk sway occurring during clinical stance and gait tasks was compared between a group of subjects with a chronic whiplash injury, resulting from an automobile collision, and a normal collective. To examine if population specific trunk sway patterns for stance and gait could be identified for chronic whiplash injury patients. Our previous work has established that it is possible to identify specific patterns of stance and gait deficits for vestibular loss (both acute and compensated) patients and those with Parkinson's disease. Our question was whether it was possible to use the same stance and gait tasks to identify patterns of trunk sway differences with respect to those of healthy subjects and individuals with a chronic whiplash injury. Twenty-five subjects with history of whiplash injury and 170 healthy age-matched control subjects participated in the study. Trunk sway angular displacements in chronic whiplash patients were assessed for a number of stance and gait tasks similar to those of the Tinetti and Clinical Test of Sensory Interaction and Balance (CTSIB) protocols. We used a lightweight, easy-to-attach, body-worn apparatus to measure trunk angular displacements and velocities in the roll (lateral) and the pitch (forward-backward) planes. Data analysis revealed several significant differences between the two groups. A pattern could be identified, showing greater trunk sway for stance tasks and for complex gait tasks that required task-specific gaze control such as walking up and down stairs. Trunk sway was less, however, for simple gait tasks that demanded large head movements but no task-specific gaze control, such as walking while rotating the head. Subjects who have a chronic whiplash injury show a characteristic pattern of trunk sway that is different from that of other patient groups with balance disorders. Balance was most unstable during gait involving task-specific head movements which possibly enhance a pathologic vestibulo-cervical interaction.
Richards, R E; Andersen, M S; Harlaar, J; van den Noort, J C
2018-04-30
To evaluate 1) the relationship between the knee contact force (KCF) and knee adduction and flexion moments (KAM and KFM) during normal gait in people with medial knee osteoarthritis (KOA), 2) the effects on the KCF of walking with a modified gait pattern and 3) the relationship between changes in the KCF and changes in the knee moments. We modeled the gait biomechanics of thirty-five patients with medial KOA using the AnyBody Modeling System during normal gait and two modified gait patterns. We calculated the internal KCF and evaluated the external joint moments (KAM and KFM) against it using linear regression analyses. First peak medial KCF was associated with first peak KAM (R 2 = 0.60) and with KAM and KFM (R 2 = 0.73). Walking with both modified gait patterns reduced KAM (P = 0.002) and the medial to total KCF ratio (P < 0.001) at the first peak. Changes in KAM during modified gait were moderately associated with changes in the medial KCF at the first peak (R 2 = 0.54 and 0.53). At the first peak, KAM is a reasonable substitute for the medial contact force, but not at the second peak. First peak KFM is also a significant contributor to the medial KCF. At the first peak, walking with a modified gait reduced the ratio of the medial to total KCF but not the medial KCF itself. To determine the effects of gait modifications on cartilage loading and disease progression, longitudinal studies and individualized modeling, accounting for motion control, would be required. Copyright © 2018 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.
Shull, Peter B; Huang, Yangjian; Schlotman, Taylor; Reinbolt, Jeffrey A
2015-09-18
While gait retraining paradigms that alter knee loads typically focus on modifying kinematics, the underlying muscle force modifications responsible for these kinematic changes remain largely unknown. As humans are generally thought to select uniform gait muscle patterns such as strategies based on fatigue cost functions or energy minimization, we hypothesized that a kinematic gait change known to reduce the knee adduction moment (i.e. toe-in gait) would be accompanied by a uniform muscle force modification strategy for individuals with symptomatic knee osteoarthritis. Ten subjects with self-reported knee pain and radiographic evidence of medial compartment knee osteoarthritis performed normal gait and toe-in gait modification walking trials. Two hundred muscle-actuated dynamic simulations (10 steps for normal gait and 10 steps from toe-in gait for each subject) were performed to determine muscle forces for each gait. Results showed that subjects internally rotated their feet during toe-in gait, which decreased the foot progression angle by 7° (p<0.01) and reduced the first peak knee adduction moment by 20% (p<0.01). While significant muscle force modifications were evidenced within individuals, there were no consistent muscle force modifications across all subjects. It may be that self-selected muscle pattern changes are not uniform for gait modification particularly for individuals with knee pain. Future studies focused on altering knee loads should not assume consistent muscle force modifications for a given kinematic gait change across subjects and should consider muscle forces in addition to kinematics in gait retraining paradigms. Copyright © 2015 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
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.
Clément, Julien; Toliopoulos, Panagiota; Hagemeister, Nicola; Desmeules, François; Fuentes, Alexandre; Vendittoli, Pascal-André
2018-06-11
Normal 3D knee kinematics during gait is still not well understood, especially regarding differences between women and men. The objective of the present study was to characterize 3D knee kinematics during gait in healthy women and men with a validated tool. Knee kinematics was analysed with the KneeKG™ system in 90 healthy subjects (49 females and 41 males). 3D knee rotations were compared between women and men, and between right and left knees. Each subject underwent full-length weight-bearing x-rays. Correlations between abduction-adduction angles and lower-limb alignment measures on x-rays were assessed. In the frontal plane, 2.0-5.0° more abduction occurred in women compared to men (0.000 ≤ p ≤ 0.015) throughout the entire gait cycle. In the transverse plane, 2.4-3.7° more external tibial rotation was seen in women than in men (0.002 ≤ p ≤ 0.041) during the initial and mid-swing phases. No difference was found between the right and left knees. Low correlations (-0.52 ≤ r≤-0.41, p < 0.001) were observed between radiographic hip-knee-ankle angle (HKA) and abduction-adduction angles throughout the stance phase. Kinematic differences between women and men in the frontal plane can be partly explained by their anatomical differences: women were less in varus than men (HKA of -0.8° vs. -2.6°, p < 0.001). Our study contributes to a better understanding of healthy 3D knee kinematics during gait and highlights the need for accounting of gender differences in future investigations. Better knowledge of natural knee kinematics will be helpful in assessing pathological gait patterns or determining the efficiency of conservative and surgical treatments to restore normal kinematics. Copyright © 2018 Elsevier B.V. All rights reserved.
NRH Neuroscience Research Center
2005-06-01
Gait Educationtf E Advanced gait 20-Patient * Community mobility Patient Assessmentt 21-Family/ caregiver ~( Formal assessment) 22-Staff Home Evaluation...interventions used. client diagnostic groups, which are termed practice patterns. Time for formal assessments, home evaluation, and work site The practice...18. Visual training 19. Sensory training Gait Education Interventions: 20. Patient 21. Family/ Caregiver Advanced Gait 22. Staff 23. Prescription
Thangavel, Pavithra; Vidhya, S; Li, Junhua; Chew, Effie; Bezerianos, Anastasios; Yu, Haoyong
2017-07-01
Since manual rehabilitation therapy can be taxing for both the patient and the physiotherapist, a gait rehabilitation robot has been built to reduce the physical strain and increase the efficacy of the rehabilitation therapy. The prototype of the gait rehabilitation robot is designed to provide assistance while walking for patients with abnormal gait pattern and it can also be used for rehabilitation therapy to restore an individual's normal gait pattern by aiding motor recovery. The Gait Rehabilitation Robot uses gait event based synchronization, which enables the exoskeleton to provide synchronous assistance during walking that aims to reduce the lower-limb muscle activation. This study emphasizes on the biomechanical effects of assisted walking on the lower limb by analyzing the EMG signal, knee joint kinematics data that was collected from the right leg during the various experimental conditions. The analysis of the measured data shows an improved knee joint trajectory and reduction in muscle activity with assistance. The result of this study does not only assess the functionality of the exoskeleton but also provides a profound understanding of the human-robot interaction by studying the effects of assistance on the lower limb.
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. Conclusion The results demonstrated that the treatment is feasible and it might be effective in translating progresses from pedaling to locomotion. If these results are confirmed on a larger and controlled scale, the intervention, thanks to its safety and low price, could have a significant impact as a home- rehabilitation treatment for chronic stroke patients. PMID:21861930
ERIC Educational Resources Information Center
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…
Adaptive gait responses to awareness of an impending slip during treadmill walking.
Yang, Feng; Kim, JaeEun; Munoz, Jose
2016-10-01
The awareness of potential slip risk has been shown to cause protective changes to human gait during overground walking. It remains unknown if such adaptations to walking pattern also exist when ambulating on a treadmill. This study sought to determine whether and to what extent individuals, when being aware of a potential slip risk during treadmill walking, could adjust their gait pattern to improve their dynamic stability against backward balance loss in response to the impending slip hazard. Fifty-four healthy young subjects (age: 23.9±4.7years) participated in this study. Subjects' gait pattern was measured under two conditions: walking on a treadmill without (or normal walking) and with (or aware walking) the awareness of the potential slip perturbation. During both walking conditions, subjects' full body kinematics were gathered by using a motion capture system. Spatial gait parameters and the dynamic gait stability against backward balance were compared between the two walking conditions. The results revealed that subjects proactively adopted a "cautious gait" during aware walking compared with the normal walking. The cautious gait, which was achieved by taking a shorter step and a more flatfoot landing, positioned the body center of mass closer to the base of support, improving participants' dynamic stability and increasing their resistance against a possible slip-related fall. The finding from this study could provide insights into the dynamic stability control when individuals anticipate potential slip risk during treadmill walking. Copyright © 2016 Elsevier B.V. All rights reserved.
Effect of Rhythmic Auditory Stimulation on Hemiplegic Gait Patterns
Shin, Yoon-Kyum; Chong, Hyun Ju
2015-01-01
Purpose The purpose of our study was to investigate the effect of gait training with rhythmic auditory stimulation (RAS) on both kinematic and temporospatial gait patterns in patients with hemiplegia. Materials and Methods Eighteen hemiplegic patients diagnosed with either cerebral palsy or stroke participated in this study. All participants underwent the 4-week gait training with RAS. The treatment was performed for 30 minutes per each session, three sessions per week. RAS was provided with rhythmic beats using a chord progression on a keyboard. Kinematic and temporospatial data were collected and analyzed using a three-dimensional motion analysis system. Results Gait training with RAS significantly improved both proximal and distal joint kinematic patterns in hip adduction, knee flexion, and ankle plantar flexion, enhancing the gait deviation index (GDI) as well as ameliorating temporal asymmetry of the stance and swing phases in patients with hemiplegia. Stroke patients with previous walking experience demonstrated significant kinematic improvement in knee flexion in mid-swing and ankle dorsiflexion in terminal stance. Among stroke patients, subacute patients showed a significantly increased GDI score compared with chronic patients. In addition, household ambulators showed a significant effect on reducing anterior tilt of the pelvis with an enhanced GDI score, while community ambulators significantly increased knee flexion in mid-swing phase and ankle dorsiflexion in terminal stance phase. Conclusion Gait training with RAS has beneficial effects on both kinematic and temporospatial patterns in patients with hemiplegia, providing not only clinical implications of locomotor rehabilitation with goal-oriented external feedback using RAS but also differential effects according to ambulatory function. PMID:26446657
Galli, Manuela; Cimolin, Veronica; Crugnola, Veronica; Priano, Lorenzo; Menegoni, Francesco; Trotti, Claudio; Milano, Eva; Mauro, Alessandro
2012-03-15
We investigated the gait pattern of 10 patients with myotonic dystrophy (Steinert disease; 4 females, 6 males; age: 41.5+7.6 years), compared to 20 healthy controls, through manual muscle test and gait analysis, in terms of kinematic, kinetic and EMG data. In most of patients (80%) distal muscle groups were weaker than proximal ones. Weakness at lower limbs was in general moderate to severe and MRC values evidenced a significant correlation between tibialis anterior and gastrocnemius medialis (R=0.91). An overall observation of gait pattern in patients when compared to controls showed that most spatio-temporal parameters (velocity, step length and cadence) were significantly different. As concerns kinematics, patients' pelvic tilt was globally in a higher position than control group, with reduced hip extension ability in stance phase and limited range of motion; 60% of the limbs revealed knee hyperextension during midstance and ankle joints showed a quite physiological position at initial contact and higher dorsiflexion during stance phase if compared to healthy individuals. Kinetic plots evidenced higher hip power during loading response and lower ankle power generation in terminal stance. The main EMG abnormalities were seen in tibialis anterior and gastrocnemius medialis muscles. In this study gait analysis gives objective and quantitative information about the gait pattern and the deviations due to the muscular situation of these patients; these results are important from a clinical point of view and suggest that rehabilitation programs for them should take these findings into account. Copyright © 2011 Elsevier B.V. All rights reserved.
Elbaz, Avi; Mor, Amit; Segal, Ganit; Aloni, Yoav; Teo, Yee Hong; Teo, Yee Sze; Das-De, Shamal; Yeo, Seng Jin
2014-01-02
Previous studies have shown the effect of a unique therapy with a non-invasive biomechanical foot-worn device (AposTherapy) on Caucasian western population suffering from knee osteoarthritis. The purpose of the current study was to evaluate the effect of this therapy on the level of symptoms and gait patterns in a multi-ethnic Singaporean population suffering from knee osteoarthritis. Fifty-eight patients with bilateral medial compartment knee osteoarthritis participated in the study. All patients underwent a computerized gait test and completed two self-assessment questionnaires (WOMAC and SF-36). The biomechanical device was calibrated to each patient, and therapy commenced. Changes in gait patterns and self-assessment questionnaires were reassessed after 3 and 6 months of therapy. A significant improvement was seen in all of the gait parameters following 6 months of therapy. Specifically, gait velocity increased by 15.9%, step length increased by 10.3%, stance phase decreased by 5.9% and single limb support phase increased by 2.7%. In addition, pain, stiffness and functional limitation significantly decreased by 68.3%, 66.7% and 75.6%, respectively. SF-36 physical score and mental score also increased significantly following 6 months of therapy (46.1% and 22.4%, respectively) (P < 0.05 for all parameters). Singaporean population with medial compartment knee osteoarthritis demonstrated improved gait patterns, reported alleviation in symptoms and improved function and quality of life following 6 months of therapy with a unique biomechanical device. Registration number NCT01562652.
Boyer, Elizabeth R; Patterson, Aleksys
2018-05-05
Trips and falls are common concerns reported by parents of children with cerebral palsy. Specific gait pathologies (excessive internal hip rotation, intoeing, and stiff knee gait) are anecdotally associated with higher rates of falls. Is fall frequency higher for the aforementioned gait pathologies? Parent-reported fall frequency from 1063 children with cerebral palsy who also had a three-dimensional gait analysis was retrospectively reviewed. Frequency of 10 common gait pathologies was determined and fall frequency for the gait pathologies of interest were compared to matched control groups. Possible effects of Gross Motor Functional Classification System (GMFCS) level and age on fall frequency were also assessed and matched in the control group, as appropriate. In general, parent-reported fall frequency increased from GMFCS level I to II and then decreased until level IV. Moreover, younger children tended to report greater fall frequency, though children who reported never falling were of similar age as those who reported weekly falls, resulting in an inverted-U shaped relationship. Children with cerebral palsy who walked with excessive internal hip rotation, excessive intoeing, or stiff knee gait did not report increased fall frequencies compared to other children with cerebral palsy matched on GMFCS level and age that did not walk with those gait patterns. Approximately 35% of children reported never falling, 35% reported falling daily, and 30% reported falling monthly or weekly for each gait pattern. Therefore, elevated fall frequency appears to be a generic problem for most children with CP rather than a function of a specific gait pattern. Clinicians should be aware of these relationships, or lack thereof, when trying to decipher the cause of a child's falling and when determining appropriate interventions. Future studies may seek to more objectively quantify fall frequency, as self-report is the main limitation of this study. Copyright © 2018 Elsevier B.V. All rights reserved.
Ancillao, Andrea; van der Krogt, Marjolein M; Buizer, Annemieke I; Witbreuk, Melinda M; Cappa, Paolo; Harlaar, Jaap
2017-10-01
Gait analysis is used for the assessment of walking ability of children with cerebral palsy (CP), to inform clinical decision making and to quantify changes after treatment. To simplify gait analysis interpretation and to quantify deviations from normality, some quantitative synthetic descriptors were developed over the years, such as the Movement Analysis Profile (MAP) and the Linear Fit Method (LFM), but their interpretation is not always straightforward. The aims of this work were to: (i) study gait changes, by means of synthetic descriptors, in children with CP that underwent Single Event Multilevel Surgery; (ii) compare the MAP and the LFM on these patients; (iii) design a new index that may overcome the limitations of the previous methods, i.e. the lack of information about the direction of deviation or its source. Gait analysis exams of 10 children with CP, pre- and post-surgery, were collected and MAP and LFM were computed. A new index was designed asa modified version of the MAP by separating out changes in offset (named OC-MAP). MAP documented an improvement in the gait pattern after surgery. The highest effect was observed for the knee flexion/extension angle. However, a worsening was observed as an increase in anterior pelvic tilt. An important source of gait deviation was recognized in the offset between observed tracks and reference. OC-MAP allowed the assessment of the offset component versus the shape component of deviation. LFM provided results similar to OC-MAP offset analysis but could not be considered reliable due to intrinsic limitations. As offset in gait features played an important role in gait deviation, OC-MAP synthetic analysis was proposed as a novel approach to a meaningful parameterisation of global deviations in gait patterns of subjects with CP and gait changes after treatment. Copyright © 2017 Elsevier B.V. All rights reserved.
Influence of altered gait patterns on the hip joint contact forces.
Carriero, Alessandra; Zavatsky, Amy; Stebbins, Julie; Theologis, Tim; Lenaerts, Gerlinde; Jonkers, Ilse; Shefelbine, Sandra J
2014-01-01
Children who exhibit gait deviations often present a range of bone deformities, particularly at the proximal femur. Altered gait may affect bone growth and lead to deformities by exerting abnormal stresses on the developing bones. The objective of this study was to calculate variations in the hip joint contact forces with different gait patterns. Muscle and hip joint contact forces of four children with different walking characteristics were calculated using an inverse dynamic analysis and a static optimisation algorithm. Kinematic and kinetic analyses were based on a generic musculoskeletal model scaled down to accommodate the dimensions of each child. Results showed that for all the children with altered gaits both the orientation and magnitude of the hip joint contact force deviated from normal. The child with the most severe gait deviations had hip joint contact forces 30% greater than normal, most likely due to the increase in muscle forces required to sustain his crouched stance. Determining how altered gait affects joint loading may help in planning treatment strategies to preserve correct loading on the bone from a young age.
Hayot, C; Sakka, S; Lacouture, P
2013-04-01
Saunders et al. (1953) stated that the introduction of six gait determinants (pelvic rotation, pelvic obliquity, stance knee flexion, foot and ankle mechanisms, and tibiofemoral angle) to a compass gait model (two rigid legs hinged at the hips) provides an accurate simulation of the actual trajectory of the whole body center of mass (CoM). Their respective actions could also explain the shape of the vertical ground reaction force (GRF) pattern. Saunders' approach is considered as a kinematic description of some features of gait and is subject to debate. The purpose of this study is to realize a rigorous mechanical evaluation of the gait determinants theory using an appropriated mathematical model in which specific experimental data of gait trials are introduced. We first simulate a compass-like CoM trajectory using the proposed 3D mathematical model. Then, factorizing the model to introduce successively the kinematic data related to each gait determinant, we assess their respective contribution to both the CoM trajectory and the pattern of vertical GRF at different gait speeds. The results show that the stance knee flexion significatively decreases the estimated position of the CoM during midstance. Stance knee extension and pelvic obliquity contribute to the appearance of the pattern of vertical GRF during stance. The stance ankle dorsiflexion significatively contributes to CoM vertical excursion and the ankle plantarflexion contributes to the vertical GRF during terminal stance. The largest contribution towards the minimization of the CoM vertical amplitude during the complete gait step appears when considering the foot mechanisms and the pelvic obliquity in the proposed model. Copyright © 2012 Elsevier B.V. All rights reserved.
Psarakis, Michael; Greene, David; Cole, Michael H; Lord, Stephen R; Hoang, Phu; Brodie, Matthew A D
2018-04-27
People with Multiple Sclerosis (PwMS) often experience a decline in gait performance, which can compromise their independence and increase falls. Ankle joint contractures in PwMS are common and often result in compensatory gait patterns to accommodate reduced ankle range of motion (ROM). Using advances in wearable technology, the aim of this study was to quantify head and pelvis movement patterns that occur in PwMS with disability and determine how these secondary gait compensations impact on gait stability. Twelve healthy participants and twelve PwMS participated in the study. Head and pelvis movements were measured using two tri-axial accelerometers. Measures of gait compensation, mobility, variability, asymmetry, stability and fatigue were assessed during a six-minute walking test. Compared to healthy controls, PwMS had greater vertical asymmetry in their head and pelvic movements (Cohen's d=1.85 & 1.60). Lower harmonic ratios indicated that PwMS were more unstable than controls (Cohen's d=-1.61 to -3.06), even after adjusting for their slower walking speeds. In the PwMS, increased compensatory movements were correlated with reduced ankle active ROM (r=-0.71), higher disability (EDSS) scores (r=0.58), unstable gait (r=-0.76), reduced mobility (r=-0.76) and increased variability (r=0.83). Wearable device technology provides an efficient and reliable way to screen for excessive compensatory movements often present in PwMS and provides clinically-important information that impacts on mobility, stride time variability and gait stability. This information may help clinicians identify PwMS at high risk of falling and develop better rehabilitation interventions that, in addition to improving mobility, may help target the underlying causes of unstable gait. © 2018 Institute of Physics and Engineering in Medicine.
How multi segmental patterns deviate in spastic diplegia from typical developed.
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.
Women with fibromyalgia walk with an altered muscle synergy.
Pierrynowski, Michael R; Tiidus, Peter M; Galea, Victoria
2005-11-01
Most individuals can use different movement and muscle recruitment patterns to perform a stated task but often only one pattern is selected which optimizes an unknown global objective given the individual's neuromusculoskeletal characteristics. Patients with fibromyalgia syndrome (FS), characterized by their chronic pain, reduced physical work capacity and muscular fatigue, could exhibit a different control signature compared to asymptomatic control volunteers (CV). To test this proposal, 22 women with FS, and 11 CV, were assessed in a gait analysis laboratory. Each subject walked repeatedly at self-selected slow, comfortable, and fast walking speeds. The gait analysis provided, for each walk, each subject's stride time, length, and velocity, and ground reaction force, and lower extremity joint kinematics, moments and powers. The data were then anthropometrically scaled and velocity normalized to reduce the influence of subject mass, leg length, and walking speed on the measured gait outcomes. Similarities and differences in the two groups' scaled and normalized gait patterns were then determined. Results show that FS and CV walk with externally similar stride lengths, times, and velocities, and joint angles and ground reaction forces but they use internally different muscle recruitment patterns. Specifically, FS preferentially power gait using their hip flexors instead of their ankle plantarflexors. Interestingly, CV use a similar muscle fatiguing recruitment pattern to walk fast which parallels the common complaint of fatigue reported by FS walking at comfortable speed.
Gait patterns in Prader-Willi and Down syndrome patients
2010-01-01
Background Prader-Willi (PWS) and Down Syndrome (DS) are two genetic disorders characterised by some common clinical and functional features. A quantitative description and comparison of their patterns would contribute to a deeper understanding of the determinants of motor disability in these two syndromes. The aim of this study was to measure gait pattern in PWS and DS in order to provide data for developing evidence-based deficit-specific or common rehabilitation strategies. Methods 19 PWS patients (17.7-40 yr) and 21 DS patients (18-39 yr) were evaluated with an optoelectronic system and force platforms for measuring kinematic and kinetic parameters during walking. The results were compared with those obtained in a group of normal-weight controls (Control Group: CG; 33.4 + 9.6 yr). Results and Discussion The results show that PWS and DS are characterised by different gait strategies. Spatio-temporal parameters indicated a cautious, abnormal gait in both groups, but DS walked with a less stable strategy than PWS. As for kinematics, DS showed a significantly reduced hip and knee flexion, especially at initial contact and ankle range of motion than PWS. DS were characterised by lower ranges of motion (p < 0.05) in all joints than CG and PWS. As for ankle kinetics, both PWS and DS showed a significantly lower push-off during terminal stance than CG, with DS yielding the lowest values. Stiffness at hip and ankle level was increased in DS. PWS showed hip stiffness values close to normal. At ankle level, stiffness was significantly decreased in both groups. Conclusions Our data show that DS walk with a less physiological gait pattern than PWS. Based on our results, PWS and DS patients need targeted rehabilitation and exercise prescription. Common to both groups is the aim to improve hypotonia, muscle strength and motor control during gait. In DS, improving pelvis and hip range of motion should represent a major specific goal to optimize gait pattern. PMID:20565926
Gait patterns in Prader-Willi and Down syndrome patients.
Cimolin, Veronica; Galli, Manuela; Grugni, Graziano; Vismara, Luca; Albertini, Giorgio; Rigoldi, Chiara; Capodaglio, Paolo
2010-06-21
Prader-Willi (PWS) and Down Syndrome (DS) are two genetic disorders characterised by some common clinical and functional features. A quantitative description and comparison of their patterns would contribute to a deeper understanding of the determinants of motor disability in these two syndromes. The aim of this study was to measure gait pattern in PWS and DS in order to provide data for developing evidence-based deficit-specific or common rehabilitation strategies. 19 PWS patients (17.7-40 yr) and 21 DS patients (18-39 yr) were evaluated with an optoelectronic system and force platforms for measuring kinematic and kinetic parameters during walking. The results were compared with those obtained in a group of normal-weight controls (Control Group: CG; 33.4 + 9.6 yr). The results show that PWS and DS are characterised by different gait strategies. Spatio-temporal parameters indicated a cautious, abnormal gait in both groups, but DS walked with a less stable strategy than PWS. As for kinematics, DS showed a significantly reduced hip and knee flexion, especially at initial contact and ankle range of motion than PWS. DS were characterised by lower ranges of motion (p < 0.05) in all joints than CG and PWS. As for ankle kinetics, both PWS and DS showed a significantly lower push-off during terminal stance than CG, with DS yielding the lowest values. Stiffness at hip and ankle level was increased in DS. PWS showed hip stiffness values close to normal. At ankle level, stiffness was significantly decreased in both groups. Our data show that DS walk with a less physiological gait pattern than PWS. Based on our results, PWS and DS patients need targeted rehabilitation and exercise prescription. Common to both groups is the aim to improve hypotonia, muscle strength and motor control during gait. In DS, improving pelvis and hip range of motion should represent a major specific goal to optimize gait pattern.
[Gait characteristics of women with fibromyalgia: a premature aging pattern].
Góes, Suelen M; Leite, Neiva; de Souza, Ricardo M; Homann, Diogo; Osiecki, Ana C V; Stefanello, Joice M F; Rodacki, André L F
2014-01-01
Fibromyalgia is a condition which involves chronic pain. Middle-aged individuals with fibromyalgia seem to exhibit changes in gait pattern, which may prematurely expose them to a gait pattern which resembles that found in the elderly population. To determine the 3D spatial (linear and angular) gait parameters of middle-aged women with fibromyalgia and compare to elderly women without this condition. 25 women (10 in the fibromyalgia group and 15 in the elderly group) volunteered to participate in the study. Kinematics was performed using an optoelectronic system, and linear and angular kinematic variables were determined. There was no difference in walking speed, stride length, cadence, hip, knee and ankle joints range of motion between groups, except the pelvic rotation, in which the fibromyalgia group showed greater rotation (P<0.05) compared to the elderly group. Also, there was a negative correlation with pelvic rotation and gluteus pain (r = -0.69; P<0.05), and between pelvic obliquity and greater trochanter pain (r = -0.69; P<0.05) in the fibromyalgia group. Middle-aged women with fibromyalgia showed gait pattern resemblances to elderly, women, which is characterized by reduced lower limb ROM, stride length and walking speed. Copyright © 2014 Elsevier Editora Ltda. All rights reserved.
Punt, Ilona M; Ziltener, Jean-Luc; Laidet, Magali; Armand, Stéphane; Allet, Lara
2015-01-01
To assess ankle function 4 weeks after conservative management and to examine the correlation of function with gait. A prospective comparison study. Thirty patients with grade I or II acute ankle sprains were followed up after 4 weeks of conservative management not involving physical therapy. Participants underwent a clinical assessment and had to walk at a normal self-selected walking speed. Their results were compared with the data of 15 healthy subjects. Participants' joint swelling, muscle strength, passive mobility, and pain were assessed. In addition, patients' temporal-spatial, kinematic, and kinetic gait data were measured while walking. Muscle strength and passive mobility were significantly reduced on the injured side compared with the noninjured side (P < .001). During gait analysis, patients with ankle sprains showed slower walking speed, shorter step length, shorter single support time, reduced and delayed maximum plantar flexion, decreased maximum power, and decreased maximum moment (P < .050) compared with healthy persons. Decreased walking speed was mainly correlated with pain (R = -0.566, P = .001) and deficits in muscle strength of dorsiflexors (R = 0.506, P = .004). Four weeks after an ankle sprain, patients who did not receive physical therapy showed physical impairments of the ankle that were correlated with gait parameters. These findings might help fine-tune rehabilitation protocols. Copyright © 2015 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.
The gait standard deviation, a single measure of kinematic variability.
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.
Gait analysis in anorexia and bulimia nervosa.
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.
Changes in in vivo knee contact forces through gait modification.
Kinney, Allison L; Besier, Thor F; Silder, Amy; Delp, Scott L; D'Lima, Darryl D; Fregly, Benjamin J
2013-03-01
Knee osteoarthritis (OA) commonly occurs in the medial compartment of the knee and has been linked to overloading of the medial articular cartilage. Gait modification represents a non-invasive treatment strategy for reducing medial compartment knee force. The purpose of this study was to evaluate the effectiveness of a variety of gait modifications that were expected to alter medial contact force. A single subject implanted with a force-measuring knee replacement walked using nine modified gait patterns, four of which involved different hiking pole configurations. Medial and lateral contact force at 25, 50, and 75% of stance phase, and the average value over all of stance phase (0-100%), were determined for each gait pattern. Changes in medial and lateral contact force values relative to the subject's normal gait pattern were determined by a Kruskal-Wallis test. Apart from early stance (25% of stance), medial contact force was most effectively reduced by walking with long hiking poles and wide pole placement, which significantly reduced medial and lateral contact force during stance phase by up to 34% (at 75% of stance) and 26% (at 50% of stance), respectively. Although this study is based on data from a single subject, the results provide important insight into changes in medial and lateral contact forces through gait modification. The results of this study suggest that an optimal configuration of bilateral hiking poles may significantly reduce both medial and lateral compartment knee forces in individuals with medial knee osteoarthritis. Copyright © 2012 Orthopaedic Research Society.
Energy-conserving impact algorithm for the heel-strike phase of gait.
Kaplan, M L; Heegaard, J H
2000-06-01
Significant ground reaction forces exceeding body weight occur during the heel-strike phase of gait. The standard methods of analytical dynamics used to solve the impact problem do not accommodate well the heel-strike collision due to the persistent contact at the front foot and presence of contact at the back foot. These methods can cause a non-physical energy gain on the order of the total kinetic energy of the system at impact. Additionally, these standard techniques do not quantify the contact force, but the impulse over the impact. We present an energy-conserving impact algorithm based on the penalty method to solve for the ground reaction forces during gait. The rigid body assumptions are relaxed and the bodies are allowed to penetrate one another to a small degree. Associated with the deformation is a potential, from which the contact forces are derived. The empirical coefficient-of-restitution used in the standard approaches is replaced by two parameters to characterize the stiffness and the damping of the materials. We solve two simple heel-strike models to illustrate the shortcomings of a standard approach and the suitability of the proposed method for use with gait.
A Quadruped Robot Exhibiting Spontaneous Gait Transitions from Walking to Trotting to Galloping.
Owaki, Dai; Ishiguro, Akio
2017-03-21
The manner in which quadrupeds change their locomotive patterns-walking, trotting, and galloping-with changing speed is poorly understood. In this paper, we provide evidence for interlimb coordination during gait transitions using a quadruped robot for which coordination between the legs can be self-organized through a simple "central pattern generator" (CPG) model. We demonstrate spontaneous gait transitions between energy-efficient patterns by changing only the parameter related to speed. Interlimb coordination was achieved with the use of local load sensing only without any preprogrammed patterns. Our model exploits physical communication through the body, suggesting that knowledge of physical communication is required to understand the leg coordination mechanism in legged animals and to establish design principles for legged robots that can reproduce flexible and efficient locomotion.
Effects of obesity on gait pattern in young individuals with Down syndrome.
Galli, Manuela; Cimolin, Veronica; Rigoldi, Chiara; Condoluci, Claudia; Albertini, Giorgio
2015-03-01
In individuals with Down syndrome (DS), the prevalence of obesity is widespread; despite this, there are no experimental studies on the effect of obesity on gait strategy in DS individuals. The aim of this study is to assess the clinical gait analysis of a group of obese individuals with DS and a group of nonobese individuals with DS to determine whether obesity produces a different gait pattern in these participants. In addition, although females and males share a similar mass, they are characterized by different fat distribution and/or accumulation; thus, the presence of differences between females and males within the two DS groups was investigated. Gait analysis data of a group of 78 young individuals with DS and 20 normal-weight participants in the 5-18-year age range were considered. Among DS individuals, 40 were classified as obese (obese DS group), whereas 38 were classified as normal weight (nonobese groups). A three-dimensional gait analysis was carried out using an optoelectronic system, force platforms and video recording. Spatiotemporal, kinematic and kinetic parameters were identified and calculated for each participant. Our results show that most of the parameters were similar in the two groups of DS participants; the only differences were in terms of stance duration, longer in the obese DS group and dorsiflexion ability during the swing phase, which was limited in the obese DS group. The two DS groups were significantly different in terms of ankle stiffness (Ka index): both groups were characterized by reduced values compared with the control group, but the obese group presented lower values with respect to nonobese participants. The data showed that females were characterized by significant modifications of gait pattern compared with males in both groups, in particular, at proximal levels, such as the hip and the pelvis. Our findings indicate that the presence of obesity exerts effects on gait pattern in DS individuals and in particular on ankle joint stiffness. These results may have special clinical relevance; the biomechanical comparison of gait in young obese and nonobese DS individuals may provide a basis for developing either specific or common rehabilitative strategies.
Strategies for Walking on a Laterally Oscillating Treadmill
NASA Technical Reports Server (NTRS)
Peters, Brian T.; Brady, Rachel A.; Bloomberg, Jacob, J.
2008-01-01
Most people use a variety of gait patterns each day. These changes can come about by voluntary actions, such as a decision to walk faster when running late. They can also be a result of both conscious and subconscious changes made to account for variation in the environmental conditions. Many factors can play a role in determining the optimal gait patterns, but the relative importance of each could vary between subjects. A goal of this study was to investigate whether subjects used consistent gait strategies when walking on an unstable support surface.
A multi-channel biomimetic neuroprosthesis to support treadmill gait training in stroke patients.
Chia, Noelia; Ambrosini, Emilia; Baccinelli, Walter; Nardone, Antonio; Monticone, Marco; Ferrigno, Giancarlo; Pedrocchi, Alessandra; Ferrante, Simona
2015-01-01
This study presents an innovative multi-channel neuroprosthesis that induces a biomimetic activation of the main lower-limb muscles during treadmill gait training to be used in the rehabilitation of stroke patients. The electrostimulation strategy replicates the physiological muscle synergies used by healthy subjects to walk on a treadmill at their self-selected speed. This strategy is mapped to the current gait sub-phases, which are identified in real time by a custom algorithm. This algorithm divides the gait cycle into six sub-phases, based on two inertial sensors placed laterally on the shanks. Therefore, the pre-defined stimulation profiles are expanded or stretched based on the actual gait pattern of each single subject. A preliminary experimental protocol, involving 10 healthy volunteers, was carried out to extract the muscle synergies and validate the gait-detection algorithm, which were afterwards used in the development of the neuroprosthesis. The feasibility of the neuroprosthesis was tested on one healthy subject who simulated different gait patterns, and a chronic stroke patient. The results showed the correct functioning of the system. A pilot study of the neurorehabilitation treatment for stroke patients is currently being carried out.
Selective motor control correlates with gait abnormality in children with cerebral palsy.
Chruscikowski, Emily; Fry, Nicola R D; Noble, Jonathan J; Gough, Martin; Shortland, Adam P
2017-02-01
Children with bilateral cerebral palsy (CP) commonly have limited selective motor control (SMC). This affects their ability to complete functional tasks. The impact of impaired SMC on walking has yet to be fully understood. Measures of SMC have been shown to correlate with specific characteristics of gait, however the impact of SMC on overall gait pattern has not been reported. This study explored SMC data collected as part of routine gait analysis in children with bilateral CP. As part of their clinical assessment, SMC was measured with the Selective Control Assessment of the Lower Extremities (SCALE) in 194 patients with bilateral cerebral palsy attending for clinical gait analysis at a single centre. Their summed SCALE score was compared with overall gait impairment, as measured by Gait Profile Score (GPS). Score on SCALE showed a significant negative correlation with GPS (r s =-0.603, p<0.001). Cerebral injuries in CP result in damage to the motor tracts responsible for SMC. Our results indicate that this damage is also associated with changes in the development of walking pattern in children with CP. Copyright © 2016 Elsevier B.V. All rights reserved.
USASOC Injury Prevention/Performance Optimization Musculoskeletal Screening Initiative
2012-11-01
gluteus medius) Poor gait pattern/ Overpronation Tibial Stress Fracture Overloading the bone due to excessive running...Excessively tight iliotibial band Hip musculature weakness (e.g. gluteus medius) Poor gait pattern/ Overpronation Tibial Stress Fracture ...Anatomic Location Specific Injuries Probable Causes All lower extremity is at risk for injury during this exercise Foot fractures Improper
2014-01-01
Background Gait analysis and research have been developed to obtain characteristics of movement patterns of people while walking. However, traditional measuring systems present different drawbacks that reduce their use and application. Among those drawbacks one can find: high price, low sampling frequency and limiting number of steps to be analyzed. Traditional measuring gait systems carry out their measurement at frequencies oscillating between 60 to 100 Hz. It can be argued about the need of higher sampling rates for gait measurements. However small displacements of the knee or hip for example, cannot be seen with low frequencies required a more detailed sampling and higher frequency sampling. Bearing this in mind, in this paper is presented a 250 Hz system based on accelerometers for gait measurement, and the particularities of knee and hip angles during gait are highlighted. Methods The system was designed with a PCI data acquisition card instrumented with an FPGA to achieve a rate sample of 250 Hz. The accelerometers were placed in thighs and legs to calculate the joint angles of hip and knee in the sagittal plane. The angles were estimated using the acceleration polygon method without integrating the acceleration and without filters. Results The gait of thirty healthy people of Mexican phenotype was analyzed over a flat floor free of obstacles. The results showed the gait phases and particularities associated with the walking style and people's laterality; the movement patterns were similar in the thirty persons. Based on the results, the particularities as the maximum amplitude in the angles and the shape in the movement patterns were related to the anthropometry and people phenotype. Conclusions The sampling frequency was essential to record 340 samples in single gait cycle and so registering the gait cycle with its particularities. In this work were recorded an average of 8 to 10 gait cycles, and the results showed variation regarding works carried out in biomechanics laboratories; this variation was related to the method and reference frame used to obtain the joint angles and the accuracy of measurement system. PMID:24684720
Martínez-Solís, Fermín; Claudio-Sánchez, Abraham; Rodríguez-Lelis, José M; Vergara-Limon, Sergio; Olivares-Peregrino, Víctor; Vargas-Treviño, Marciano
2014-03-31
Gait analysis and research have been developed to obtain characteristics of movement patterns of people while walking. However, traditional measuring systems present different drawbacks that reduce their use and application. Among those drawbacks one can find: high price, low sampling frequency and limiting number of steps to be analyzed. Traditional measuring gait systems carry out their measurement at frequencies oscillating between 60 to 100 Hz. It can be argued about the need of higher sampling rates for gait measurements. However small displacements of the knee or hip for example, cannot be seen with low frequencies required a more detailed sampling and higher frequency sampling. Bearing this in mind, in this paper is presented a 250 Hz system based on accelerometers for gait measurement, and the particularities of knee and hip angles during gait are highlighted. The system was designed with a PCI data acquisition card instrumented with an FPGA to achieve a rate sample of 250 Hz. The accelerometers were placed in thighs and legs to calculate the joint angles of hip and knee in the sagittal plane. The angles were estimated using the acceleration polygon method without integrating the acceleration and without filters. The gait of thirty healthy people of Mexican phenotype was analyzed over a flat floor free of obstacles. The results showed the gait phases and particularities associated with the walking style and people's laterality; the movement patterns were similar in the thirty persons. Based on the results, the particularities as the maximum amplitude in the angles and the shape in the movement patterns were related to the anthropometry and people phenotype. The sampling frequency was essential to record 340 samples in single gait cycle and so registering the gait cycle with its particularities. In this work were recorded an average of 8 to 10 gait cycles, and the results showed variation regarding works carried out in biomechanics laboratories; this variation was related to the method and reference frame used to obtain the joint angles and the accuracy of measurement system.
Chen, CH; Li, JS; Hosseini, A; Gadikota, HR; Gill, TJ; Li, G
2011-01-01
Quadriceps avoidance and higher flexion strategy have been assumed as effects of ACL deficiency on knee joint function during gait. However, the effect of ACL deficiency on anteroposterior stability of the knee during gait is not well defined. In this study, ten patients with unilateral acute ACL ruptures and the contralateral side intact performed gait on a treadmill. Flexion angles and anteroposterior translation of the ACL injured and the intact controlateral knees were measured at every 10% of the stance phase of the gait (from heel strike to toe-off) using a combined MRI and dual fluoroscopic image system (DFIS). The data indicated that during the stance phase of the gait, the ACL-deficient knees showed higher flexion angles compared to the intact contralateral side, consistent with the assumption of a higher flexion gait strategy. However, the data also revealed that the ACL-deficient knees had higher anterior tibial translation compared to the intact contralateral side during the stance phase of the gait. The higher flexion gait strategy was not shown to correlate to a reduction of the anterior tibial translation in ACL deficient knees. These data may provide indications for conservative treatment or surgical reconstruction of the ACL injured knees in restoration of the knee kinematics during daily walking activities. PMID:22169387
Rajachandrakumar, Roshanth; Fraser, Julia E; Schinkel-Ivy, Alison; Inness, Elizabeth L; Biasin, Lou; Brunton, Karen; McIlroy, William E; Mansfield, Avril
2017-02-01
Anticipatory postural adjustments, executed prior to gait initiation, help preserve lateral stability when stepping. Atypical patterns of anticipatory activity prior to gait initiation may occur in individuals with unilateral impairment (e.g., stroke). This study aimed to determine the prevalence, correlates, and consequences of atypical anticipatory postural adjustment patterns prior to gait initiation in a sub-acute stroke population. Forty independently-ambulatory individuals with sub-acute stroke stood on two force plates and initiated gait at a self-selected speed. Medio-lateral centre of pressure displacement was calculated and used to define anticipatory postural adjustments (shift in medio-lateral centre of pressure >10mm from baseline). Stroke severity, motor recovery, and functional balance and mobility status were also obtained. Three patterns were identified: single (typical), absent (atypical), and multiple (atypical) anticipatory postural adjustments. Thirty-five percent of trials had atypical anticipatory postural adjustments (absent and multiple). Frequency of absent anticipatory postural adjustments was negatively correlated with walking speed. Multiple anticipatory postural adjustments were more prevalent when leading with the non-paretic than the paretic limb. Trials with multiple anticipatory postural adjustments had longer duration of anticipatory postural adjustment and time to foot-off, and shorter unloading time than trials with single anticipatory postural adjustments. A high prevalence of atypical anticipatory control prior to gait initiation was found in individuals with stroke. Temporal differences were identified with multiple anticipatory postural adjustments, indicating altered gait initiation. These findings provide insight into postural control during gait initiation in individuals with sub-acute stroke, and may inform interventions to improve ambulation in this population. Copyright © 2016 Elsevier B.V. All rights reserved.
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 < .001; diabetic group, F(5,172) = 3.45, p < .001). Post hoc analyses showed early 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 < .001) and average (2mph, t = 2.97, p < .05) trials. By the fast (2.5mph) ambulation trial, both groups were performing equally, suggesting a rapid rate of adjustment to the device. No technical failures from 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.
Nyakatura, John A; Heymann, Eckhard W
2010-03-01
The adoption of a specific gait sequence pattern during symmetrical locomotion has been proposed to have been a key advantage for the exploitation of the fine branch niche in early primates. Diverse aspects of primate locomotion have been extensively studied in technically equipped laboratory settings, but evolutionary conclusions derived from these investigations have rarely been verified in wild primates. Bridging the gap from the lab to the field, we conducted an actual performance determination of symmetrical gaits in two free-ranging tamarin species (Saguinus mystax and Saguinus fuscicollis) of Amazonian Peru by analyzing high-speed video recordings of naturally occurring locomotor bouts. Tamarins arguably represent viable models for aspects of early primate locomotion. We tested three specific hypotheses derived from laboratory studies to test for the influence of support size and orientation and to gain further insight into the functional significance of primate gait sequence patterns: (1) The tamarins utilize symmetrical gaits at a higher rate on small supports than on larger ones. (2) During symmetrical locomotion on small supports, diagonal sequences are utilized at a higher rate than on larger supports. (3) On inclines, diagonal sequences are predominantly used and on declines, lateral sequences are predominantly used. Our results corroborated hypotheses 1 and 3. We found no clear support for hypothesis 2. In conclusion, our results add to the notion that primate gait plasticity, rather than uniform adoption of diagonal sequence gaits, enabled early primates to accommodate different support types and effectively exploit the small branch niche. Copyright 2009 Elsevier Ltd. All rights reserved.
Influence of Systematic Increases in Treadmill Walking Speed on Gait Kinematics After Stroke
Tyrell, Christine M.; Roos, Margaret A.; Rudolph, Katherine S.
2011-01-01
Background Fast treadmill training improves walking speed to a greater extent than training at a self-selected speed after stroke. It is unclear whether fast treadmill walking facilitates a more normal gait pattern after stroke, as has been suggested for treadmill training at self-selected speeds. Given the massed stepping practice that occurs during treadmill training, it is important for therapists to understand how the treadmill speed selected influences the gait pattern that is practiced on the treadmill. Objective The purpose of this study was to characterize the effect of systematic increases in treadmill speed on common gait deviations observed after stroke. Design A repeated-measures design was used. Methods Twenty patients with stroke walked on a treadmill at their self-selected walking speed, their fastest speed, and 2 speeds in between. Using a motion capture system, spatiotemporal gait parameters and kinematic gait compensations were measured. Results Significant improvements in paretic- and nonparetic-limb step length and in single- and double-limb support were found. Asymmetry of these measures improved only for step length. Significant improvements in paretic hip extension, trailing limb position, and knee flexion during swing also were found as speed increased. No increases in circumduction or hip hiking were found with increasing speed. Limitations Caution should be used when generalizing these results to survivors of a stroke with a self-selected walking speed of less than 0.4 m/s. This study did not address changes with speed during overground walking. Conclusions Faster treadmill walking facilitates a more normal walking pattern after stroke, without concomitant increases in common gait compensations, such as circumduction. The improvements in gait deviations were observed with small increases in walking speed. PMID:21252308
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
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 < 0.01). The kinesiologic electromyogram of selected lower-limb muscles revealed a more physiologic pattern. The confounding influence of spontaneous recovery, the lack of a control group, and the double amount of therapy limit the clinical relevance of this study. Nevertheless, the gait trainer seems feasible as an adjunctive tool in gait rehabilitation after stroke; further studies are needed.
A Robust Parameterization of Human Gait Patterns Across Phase-Shifting Perturbations
Villarreal, Dario J.; Poonawala, Hasan A.; Gregg, Robert D.
2016-01-01
The phase of human gait is difficult to quantify accurately in the presence of disturbances. In contrast, recent bipedal robots use time-independent controllers relying on a mechanical phase variable to synchronize joint patterns through the gait cycle. This concept has inspired studies to determine if human joint patterns can also be parameterized by a mechanical variable. Although many phase variable candidates have been proposed, it remains unclear which, if any, provide a robust representation of phase for human gait analysis or control. In this paper we analytically derive an ideal phase variable (the hip phase angle) that is provably monotonic and bounded throughout the gait cycle. To examine the robustness of this phase variable, ten able-bodied human subjects walked over a platform that randomly applied phase-shifting perturbations to the stance leg. A statistical analysis found the correlations between nominal and perturbed joint trajectories to be significantly greater when parameterized by the hip phase angle (0.95+) than by time or a different phase variable. The hip phase angle also best parameterized the transient errors about the nominal periodic orbit. Finally, interlimb phasing was best explained by local (ipsilateral) hip phase angles that are synchronized during the double-support period. PMID:27187967
Gait alterations can reduce the risk of edge loading.
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.
Khandoker, Ahsan H; Karmakar, Chandan K; Begg, Rezaul K; Palaniswami, Marimuthu
2007-01-01
As humans age or are influenced by pathology of the neuromuscular system, gait patterns are known to adjust, accommodating for reduced function in the balance control system. The aim of this study was to investigate the effectiveness of a wavelet based multiscale analysis of a gait variable [minimum toe clearance (MTC)] in deriving indexes for understanding age-related declines in gait performance and screening of balance impairments in the elderly. MTC during walking on a treadmill for 30 healthy young, 27 healthy elderly and 10 falls risk elderly subjects with a history of tripping falls were analyzed. The MTC signal from each subject was decomposed to eight detailed signals at different wavelet scales by using the discrete wavelet transform. The variances of detailed signals at scales 8 to 1 were calculated. The multiscale exponent (beta) was then estimated from the slope of the variance progression at successive scales. The variance at scale 5 was significantly (p<0.01) different between young and healthy elderly group. Results also suggest that the Beta between scales 1 to 2 are effective for recognizing falls risk gait patterns. Results have implication for quantifying gait dynamics in normal, ageing and pathological conditions. Early detection of gait pattern changes due to ageing and balance impairments using wavelet-based multiscale analysis might provide the opportunity to initiate preemptive measures to be undertaken to avoid injurious falls.
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 < 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.
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.
Functional asymmetry of gait in children and youth with low-grade scoliosis.
Nowotny-Czupryna, Olga; Nowotny, Janusz; Brzek, Anna; Czupryna, Krzysztof
2006-04-28
Background. Compensation for abnormal alignment of body parts in scoliosis may occur above or below the pelvis. This manifests as dislocation of body parts or changes in the angular composition of the lower limbs. Compensation for unbalanced body arrangement through changes in pelvic tilt and lower limb joints are typically reflected in the gait pattern of the person with scoliosis. The aim of our research was to determine whether and how improper body arrangement in the frontal plane is reflected in the gait pattern of children and youth with lower degree scolioses. Material and method. Children and youth with scolioses of varying grade were examined. In addition to photogrammetric body posture examination, three-dimensional gait analysis was performed during particular gait phases. For each examined child the results of this analysis were compared to the posture parameters. Results. Varying signs of gait asymmetry were observed in the whole group of children and youth with scoliosis. The symptoms were connected with both general gait attributes (unisommetry and unisochrony) and further gait markers. The most obvious changes were observed in pelvis rotation during the swing phase and excessive pelvis elevation during the mid-stance phase. These deviations did not correlate significantly with the results of the static examination. Conclusions. The gait asymmetries observed in children and youth with low-grade scoliosis are non-specific, and probably depend on the individual capabilities of each person to compensate for deficiencies.
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.
Multifractal detrended cross correlation analysis of neuro-degenerative diseases-An in depth study
NASA Astrophysics Data System (ADS)
Dutta, Srimonti; Ghosh, Dipak; Chatterjee, Sucharita
2018-02-01
This work revisits our previous study on human gait diseases, (Dutta et al., 2013) where we have studied the autocorrelation of human gait pattern in normal and diseased set. Significant difference in results was observed for normal and diseased set. However we were not able to distinguish between sets of Parkinson's and Huntington's disease. In this paper we attempt to study whether cross correlations between two feet of human gait pattern can help to distinguish between different diseased set. The results reveal that study of cross correlations can help to distinguish between Parkinson's and Huntington's disease.
McGinnis, Ryan S; Mahadevan, Nikhil; Moon, Yaejin; Seagers, Kirsten; Sheth, Nirav; Wright, John A; DiCristofaro, Steven; Silva, Ikaro; Jortberg, Elise; Ceruolo, Melissa; Pindado, Jesus A; Sosnoff, Jacob; Ghaffari, Roozbeh; Patel, Shyamal
2017-01-01
Gait speed is a powerful clinical marker for mobility impairment in patients suffering from neurological disorders. However, assessment of gait speed in coordination with delivery of comprehensive care is usually constrained to clinical environments and is often limited due to mounting demands on the availability of trained clinical staff. These limitations in assessment design could give rise to poor ecological validity and limited ability to tailor interventions to individual patients. Recent advances in wearable sensor technologies have fostered the development of new methods for monitoring parameters that characterize mobility impairment, such as gait speed, outside the clinic, and therefore address many of the limitations associated with clinical assessments. However, these methods are often validated using normal gait patterns; and extending their utility to subjects with gait impairments continues to be a challenge. In this paper, we present a machine learning method for estimating gait speed using a configurable array of skin-mounted, conformal accelerometers. We establish the accuracy of this technique on treadmill walking data from subjects with normal gait patterns and subjects with multiple sclerosis-induced gait impairments. For subjects with normal gait, the best performing model systematically overestimates speed by only 0.01 m/s, detects changes in speed to within less than 1%, and achieves a root-mean-square-error of 0.12 m/s. Extending these models trained on normal gait to subjects with gait impairments yields only minor changes in model performance. For example, for subjects with gait impairments, the best performing model systematically overestimates speed by 0.01 m/s, quantifies changes in speed to within 1%, and achieves a root-mean-square-error of 0.14 m/s. Additional analyses demonstrate that there is no correlation between gait speed estimation error and impairment severity, and that the estimated speeds maintain the clinical significance of ground truth speed in this population. These results support the use of wearable accelerometer arrays for estimating walking speed in normal subjects and their extension to MS patient cohorts with gait impairment.
Lura, Derek J; Wernke, Matthew W; Carey, Stephanie L; Kahle, Jason T; Miro, Rebecca M; Highsmith, M Jason
2017-10-01
This study was a randomized crossover of stair ambulation of Transfemoral Amputees (TFAs) using the Genium and C-Leg prosthetic knees. TFAs typically have difficulty ascending and descending stairs, limiting community mobility. The objective of this study was to determine the relative efficacy of the Genium and C-Leg prostheses for stair ascent and descent, and their absolute efficacy relative to non-amputees. Twenty TFAs, and five non-amputees participated in the study. TFAs were randomized to begin the study with the Genium or C-Leg prosthesis. Informed consent was obtained from all participants prior to data collection and the study was listed on clinicaltrials.gov (#NCT01473662). After fitting, accommodation, and training, participants were asked to demonstrate their preferred gait pattern for stair ascent and descent and a step-over-step pattern if able. TFAs then switched prosthetic legs and repeated fitting, accommodation, training, and testing. An eight camera Vicon optical motion analysis system, and two AMTI force plates were used to track and analyze the participants' gait patterns, knee flexion angles, knee moment normalized by body weight, and swing time. For stair descent, no significant differences were found between prostheses. For stair ascent, Genium use resulted in: increased ability to use a step-over-step gait pattern (p=0.03), increased prosthetic side peak knee flexion (p<0.01), and increased swing duration (p<0.01). Changes in contralateral side outcomes and in knee moment were not significant. Overall the Genium knee decreased deficiency in gait patterns for stair ascent relative to the C-Leg, by enabling gait patterns that more closely resembled non-amputees. Copyright © 2017 Elsevier B.V. All rights reserved.
When human walking becomes random walking: fractal analysis and modeling of gait rhythm fluctuations
NASA Astrophysics Data System (ADS)
Hausdorff, Jeffrey M.; Ashkenazy, Yosef; Peng, Chang-K.; Ivanov, Plamen Ch.; Stanley, H. Eugene; Goldberger, Ary L.
2001-12-01
We present a random walk, fractal analysis of the stride-to-stride fluctuations in the human gait rhythm. The gait of healthy young adults is scale-free with long-range correlations extending over hundreds of strides. This fractal scaling changes characteristically with maturation in children and older adults and becomes almost completely uncorrelated with certain neurologic diseases. Stochastic modeling of the gait rhythm dynamics, based on transitions between different “neural centers”, reproduces distinctive statistical properties of the gait pattern. By tuning one model parameter, the hopping (transition) range, the model can describe alterations in gait dynamics from childhood to adulthood - including a decrease in the correlation and volatility exponents with maturation.
Palmerini, Luca; Rocchi, Laura; Mazilu, Sinziana; Gazit, Eran; Hausdorff, Jeffrey M.; Chiari, Lorenzo
2017-01-01
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. PMID:28855887
Sung, Paul S; Zipple, J Tim; Danial, Pamela
2017-04-01
New insight regarding limb-dominance effects on temporal-spatial gait parameters is needed to further investigate subjects with recurrent low back pain (LBP). Although an asymmetrical gait pattern was found to reflect natural functional differences, there is a lack of information regarding gender differences on dominant limb support patterns in subjects with LBP. The purpose of this study was to investigate temporal-spatial gait parameters based on limb dominance and gender between subjects with and without LBP. One hundred and ten right limb dominant older adults (51 subjects with LBP and 59 control subjects) participated in the study. A three-dimensional motion capture system was utilized to measure temporal-spatial gait parameters, including initial double, single, and terminal double limb support times and walking speed. The gender differences between subjects with and without LBP were analyzed based on dominance for those parameters. Overall, limb dominance demonstrated significant differences on single and terminal double limb support times as well as walking speed. Limb dominance also demonstrated interactions on group x gender for single limb support time and walking speed. The male subjects with LBP demonstrated significantly increased single limb support times on the non-dominant limb. The significant gender and group interactions based on limb dominance account for a possible pain avoidance, asymmetrical limb support pattern. The causal pathway in dominance dependency gait by unweighted ambulation might be considered as an intervention for correcting these gait deviations in subjects with LBP. The specific modification recovery profiles of the subjects with LBP could shed light on variability of current LBP experiences of the subjects and reasons for gait deviations. Clinicians need to consider the mechanism of dominant limb dependency, which requires postural control strategies in male subjects with recurrent LBP. Copyright © 2017 Elsevier B.V. All rights reserved.
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 limb circumduction during aquatic treadmill walking. Copyright (c) 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
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 (BMI<25), overweight (25≤BMI≤30), and obese (BMI>30). 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.
Chen, Chih-Hui; Li, Jing-Sheng; Hosseini, Ali; Gadikota, Hemanth R; Gill, Thomas J; Li, Guoan
2012-03-01
Quadriceps avoidance and higher flexion strategies have been assumed as effects of ACL deficiency on knee joint function during gait. However, the effect of ACL deficiency on anteroposterior stability of the knee during gait is not well defined. In this study, 10 patients with unilateral acute ACL ruptures and the contralateral side intact performed gait on a treadmill. Flexion angles and anteroposterior translation of the ACL injured and the intact controlateral knees were measured at every 10% of the stance phase of the gait (from heel strike to toe-off) using a combined MRI and dual fluoroscopic imaging system (DFIS). The data indicated that during the stance phase of the gait, the ACL-deficient knees showed higher flexion angles compared to the intact contralateral side, consistent with the assumption of a higher flexion gait strategy. However, the data also revealed that the ACL-deficient knees had higher anterior tibial translation compared to the intact contralateral side during the stance phase of the gait. The higher flexion gait strategy was not shown to correlate to a reduction of the anterior tibial translation in ACL deficient knees. These data may provide indications for conservative treatment or surgical reconstruction of the ACL injured knees in restoration of the knee kinematics during daily walking activities. Copyright © 2011 Elsevier B.V. All rights reserved.
2013-01-01
Background 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. Methods 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. Results 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. Conclusions 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. PMID:23819439
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.
ERIC Educational Resources Information Center
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…
Gait performance is not influenced by working memory when walking at a self-selected pace.
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.
Design of Human-Machine Interface and altering of pelvic obliquity with RGR Trainer.
Pietrusinski, Maciej; Unluhisarcikli, Ozer; Mavroidis, Constantinos; Cajigas, Iahn; Bonato, Paolo
2011-01-01
The Robotic Gait Rehabilitation (RGR) Trainer targets secondary gait deviations in stroke survivors undergoing rehabilitation. Using an impedance control strategy and a linear electromagnetic actuator, the device generates a force field to control pelvic obliquity through a Human-Machine Interface (i.e. a lower body exoskeleton). Herein we describe the design of the RGR Trainer Human-Machine Interface (HMI) and we demonstrate the system's ability to alter the pattern of movement of the pelvis during gait in a healthy subject. Results are shown for experiments during which we induced hip-hiking - in healthy subjects. Our findings indicate that the RGR Trainer has the ability of affecting pelvic obliquity during gait. Furthermore, we provide preliminary evidence of short-term retention of the modified pelvic obliquity pattern induced by the RGR Trainer. © 2011 IEEE
Design of Human – Machine Interface and Altering of Pelvic Obliquity with RGR Trainer
Pietrusinski, Maciej; Unluhisarcikli, Ozer; Mavroidis, Constantinos; Cajigas, Iahn; Bonato, Paolo
2012-01-01
The Robotic Gait Rehabilitation (RGR) Trainer targets secondary gait deviations in stroke survivors undergoing rehabilitation. Using an impedance control strategy and a linear electromagnetic actuator, the device generates a force field to control pelvic obliquity through a Human-Machine Interface (i.e. a lower body exoskeleton). Herein we describe the design of the RGR Trainer Human-Machine Interface (HMI) and we demonstrate the system’s ability to alter the pattern of movement of the pelvis during gait in a healthy subject. Results are shown for experiments during which we induced hip-hiking – in healthy subjects. Our findings indicate that the RGR Trainer has the ability of affecting pelvic obliquity during gait. Furthermore, we provide preliminary evidence of short-term retention of the modified pelvic obliquity pattern induced by the RGR Trainer. PMID:22275693
Biffi, E; Beretta, E; Diella, E; Panzeri, D; Maghini, C; Turconi, A C; Strazzer, S; Reni, G
2015-01-01
The Gait Real-time Analysis Interactive Lab (GRAIL) is an instrumented multi-sensor platform based on immersive virtual reality for gait training and rehabilitation. Few studies have been included GRAIL to evaluate gait patterns in normal and disabled people and to improve gait in adults, while at our knowledge no evidence on its use for the rehabilitation of children is available. In this study, 4 children suffering from acquired brain injury (ABI) underwent a 5 session treatment with GRAIL, to improve walking and balance ability in engaging VR environments. The first and the last sessions were partially dedicated to gait evaluation. Results are promising: improvements were recorded at the ankle level, selectively at the affected side, and at the pelvic level, while small changes were measured at the hip and knee joints, which were already comparable to healthy subjects. All these changes also conveyed advances in the symmetry of the walking pattern. In the next future, a longer intervention will be proposed and more children will be enrolled to strongly prove the effectiveness of GRAIL in the rehabilitation of children with ABI.
Femoral neck shortening after internal fixation of a femoral neck fracture.
Zielinski, Stephanie M; Keijsers, Noël L; Praet, Stephan F E; Heetveld, Martin J; Bhandari, Mohit; Wilssens, Jean Pierre; Patka, Peter; Van Lieshout, Esther M M
2013-07-01
This study assesses femoral neck shortening and its effect on gait pattern and muscle strength in patients with femoral neck fractures treated with internal fixation. Seventy-six patients from a multicenter randomized controlled trial participated. Patient characteristics and Short Form 12 and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were collected. Femoral neck shortening, gait parameters, and maximum isometric forces of the hip muscles were measured and differences between the fractured and contralateral leg were calculated. Variables of patients with little or no shortening, moderate shortening, and severe shortening were compared using univariate and multivariate analyses. Median femoral neck shortening was 1.1 cm. Subtle changes in gait pattern, reduced gait velocity, and reduced abductor muscle strength were observed. Age, weight, and Pauwels classification were risk factors for femoral neck shortening. Femoral neck shortening decreased gait velocity and seemed to impair gait symmetry and physical functioning. In conclusion, internal fixation of femoral neck fractures results in permanent physical limitations. The relatively young and healthy patients in our study seem capable of compensating. Attention should be paid to femoral neck shortening and proper correction with a heel lift, as inadequate correction may cause physical complaints and influence outcome. Copyright 2013, SLACK Incorporated.
Lobet, S; Detrembleur, C; Francq, B; Hermans, C
2010-09-01
A major complication in haemophilia is the destruction of joint cartilage because of recurrent intraarticular and intramuscular bleeds. Therefore, joint assessment is critical to quantify the extent of joint damage, which has traditionally been evaluated using both radiological and clinical joint scores. Our study aimed to evaluate the natural progression of haemophilic arthopathy using three-dimensional gait analysis (3DGA) and to assess the reproducibility of this technique. We hypothesized that the musculoskeletal function was relatively stable in patients with haemophilia. Eighteen adults with established haemophilic arthropathies were evaluated twice by 3DGA (mean follow-up: 18 +/- 5 weeks). Unexpectedly, our findings revealed infraclinical deterioration of gait pattern, characterized by a 3.2% decrease in the recovery index, which is indicative of the subject's ability to save energy while walking. A tendency towards modification of segmental joint function was also observed. Gait analysis was sufficiently reproducible with regards to spatiotemporal parameters as well as kinetic, mechanical and energetic gait variables. The kinematic variables were reproducible in both the sagittal and frontal planes. In conclusion, 3DGA is a reproducible tool to assess abnormal gait patterns and monitor natural disease progression in haemophilic patients.
A mechanized gait trainer for restoration of gait.
Hesse, S; Uhlenbrock, D
2000-01-01
The newly developed gait trainer allows wheel-chair-bound subjects the repetitive practice of a gait-like movement without overstressing therapists. The device simulates the phases of gait, supports the subjects according to their abilities, and controls the center of mass (CoM) in the vertical and horizontal directions. The patterns of sagittal lower limb joint kinematics and of muscle activation for a normal subject were similar when using the mechanized 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 were required to support treadmill walking. Gait movements on the trainer were highly symmetrical, impact free, and less spastic. The vertical displacement of the CoM was bi-phasic instead of mono-phasic during each gait cycle on the new device. Two cases of non-ambulatory patients, who regained their walking ability after 4 weeks of daily training on the gait trainer, are reported.
Effects of unilateral robotic limb loading on gait characteristics in subjects with chronic stroke.
Khanna, Ira; Roy, Anindo; Rodgers, Mary M; Krebs, Hermano I; Macko, Richard M; Forrester, Larry W
2010-05-21
Hemiparesis after stroke often leads to impaired ankle motor control that impacts gait function. In recent studies, robotic devices have been developed to address this impairment. While capable of imparting forces to assist during training and gait, these devices add mass to the paretic leg which might encumber patients' gait pattern. The purpose of this study was to assess the effects of the added mass of one of these robots, the MIT's Anklebot, while unpowered, on gait of chronic stroke survivors during overground and treadmill walking. Nine chronic stroke survivors walked overground and on a treadmill with and without the anklebot mounted on the paretic leg. Gait parameters, interlimb symmetry, and joint kinematics were collected for the four conditions. Repeated-measures analysis of variance (ANOVA) tests were conducted to examine for possible differences across four conditions for the paretic and nonparetic leg. The added inertia and friction of the unpowered anklebot had no statistically significant effect on spatio-temporal parameters of gait, including paretic and nonparetic step time and stance percentage, in both overground and treadmill conditions. Noteworthy, interlimb symmetry as characterized by relative stance duration was greater on the treadmill than overground regardless of loading conditions. The presence of the unpowered robot loading reduced the nonparetic knee peak flexion on the treadmill and paretic peak dorsiflexion overground (p < 0.05). Our results suggest that for these subjects the added inertia and friction of this backdriveable robot did not significantly alter their gait pattern.
Maiwald, Christian; Arndt, Anton; Nester, Chris; Jones, Richard; Lundberg, Arne; Wolf, Peter
2017-02-01
Bone anchored markers using intracortical bone pins are one of the few available methods for analyzing skeletal motion during human gait in-vivo without errors induced by soft tissue artifacts. However, bone anchored markers require local anesthesia and may alter the motor control and motor output during gait. The purpose of this study was to examine the effect of local anesthesia and the use of bone anchored markers on typical gait analysis variables. Five subjects were analyzed in two different gait analysis sessions. In the first session, a protocol with skin markers was used. In the second session, bone anchored markers were added after local anesthesia was applied. For both sessions, three dimensional infrared kinematics of the calcaneus and tibia segments, ground reaction forces, and plantar pressure data were collected. 95% confidence intervals and boxplots were used to compare protocols and assess the data distribution and data variability for each subject. Although considerable variation was found between subjects, within-subject comparison of the two protocols revealed non-systematic effects on the target variables. Two of the five subjects walked at reduced gait speed during the bone pin session, which explained the between-session differences found in kinetic and kinematic variables. The remaining three subjects did not systematically alter their gait pattern between the two sessions. Results support the hypothesis that local anesthesia and the presence of bone pins still allow a valid gait pattern to be analyzed. Copyright © 2016 Elsevier B.V. All rights reserved.
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.
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.
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
Gait ataxia in humans: vestibular and cerebellar control of dynamic stability.
Schniepp, Roman; Möhwald, Ken; Wuehr, Max
2017-10-01
During human locomotion, vestibular feedback control is fundamental for maintaining dynamic stability and adapting the gait pattern to external circumstances. Within the supraspinal locomotor network, the cerebellum represents the key site for the integration of vestibular feedback information. The cerebellum is further important for the fine-tuning and coordination of limb movements during walking. The aim of this review article is to highlight the shared structural and functional sensorimotor principles in vestibular and cerebellar locomotion control. Vestibular feedback for the maintenance of dynamic stability is integrated into the locomotor pattern via midline, caudal cerebellar structures (vermis, flocculonodular lobe). Hemispheric regions of the cerebellum facilitate feed-forward control of multi-joint coordination and higher locomotor functions. Characteristic features of the gait disorder in patients with vestibular deficits or cerebellar ataxia are increased levels of spatiotemporal gait variability in the fore-aft and the medio-lateral gait dimension. In the fore-aft dimension, pathologic increases of gait fluctuations critically depend on the locomotion speed and predominantly manifest during slow walking velocities. This feature is associated with an increased risk of falls in both patients with vestibular hypofunction as well as patients with cerebellar ataxia. Pharmacological approaches for the treatment of vestibular or cerebellar gait ataxia are currently not available. However, new promising options are currently tested in randomized, controlled trials (fampridine/FACEG; acetyl-DL-leucine/ALCAT).
Gait analysis in children with cerebral palsy.
Armand, Stéphane; Decoulon, Geraldo; Bonnefoy-Mazure, Alice
2016-12-01
Cerebral palsy (CP) children present complex and heterogeneous motor disorders that cause gait deviations.Clinical gait analysis (CGA) is needed to identify, understand and support the management of gait deviations in CP. CGA assesses a large amount of quantitative data concerning patients' gait characteristics, such as video, kinematics, kinetics, electromyography and plantar pressure data.Common gait deviations in CP can be grouped into the gait patterns of spastic hemiplegia (drop foot, equinus with different knee positions) and spastic diplegia (true equinus, jump, apparent equinus and crouch) to facilitate communication. However, gait deviations in CP tend to be a continuum of deviations rather than well delineated groups. To interpret CGA, it is necessary to link gait deviations to clinical impairments and to distinguish primary gait deviations from compensatory strategies.CGA does not tell us how to treat a CP patient, but can provide objective identification of gait deviations and further the understanding of gait deviations. Numerous treatment options are available to manage gait deviations in CP. Generally, treatments strive to limit secondary deformations, re-establish the lever arm function and preserve muscle strength.Additional roles of CGA are to better understand the effects of treatments on gait deviations. Cite this article: Armand S, Decoulon G, Bonnefoy-Mazure A. Gait analysis in children with cerebral palsy. EFORT Open Rev 2016;1:448-460. DOI: 10.1302/2058-5241.1.000052.
Ardestani, Marzieh Mostafavizadeh; Chen, Zhenxian; Wang, Ling; Lian, Qin; Liu, Yaxiong; He, Jiankang; Li, Dichen; Jin, Zhongmin
2014-10-01
There is a growing interest in non-surgical gait rehabilitation treatments to reduce the loading in the knee joint. In particular, synergetic kinematic changes required for joint offloading should be determined individually for each subject. Previous studies for gait rehabilitation designs are typically relied on a "trial-and-error" approach, using multi-body dynamic (MBD) analysis. However MBD is fairly time demanding which prevents it to be used iteratively for each subject. This study employed an artificial neural network to develop a cost-effective computational framework for designing gait rehabilitation patterns. A feed forward artificial neural network (FFANN) was trained based on a number of experimental gait trials obtained from literature. The trained network was then hired to calculate the appropriate kinematic waveforms (output) needed to achieve desired knee joint loading patterns (input). An auxiliary neural network was also developed to update the ground reaction force and moment profiles with respect to the predicted kinematic waveforms. The feasibility and efficiency of the predicted kinematic patterns were then evaluated through MBD analysis. Results showed that FFANN-based predicted kinematics could effectively decrease the total knee joint reaction forces. Peak values of the resultant knee joint forces, with respect to the bodyweight (BW), were reduced by 20% BW and 25% BW in the midstance and the terminal stance phases. Impulse values of the knee joint loading patterns were also decreased by 17% BW*s and 24%BW*s in the corresponding phases. The FFANN-based framework suggested a cost-effective forward solution which directly calculated the kinematic variations needed to implement a given desired knee joint loading pattern. It is therefore expected that this approach provides potential advantages and further insights into knee rehabilitation designs. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.
Hussain, Shahid; Jamwal, Prashant K; Ghayesh, Mergen H
2017-05-01
While body weight support (BWS) intonation is vital during conventional gait training of neurologically challenged subjects, it is important to evaluate its effect during robot assisted gait training. In the present research we have studied the effect of BWS intonation on muscle activities during robotic gait training using dynamic simulations. Two dimensional (2-D) musculoskeletal model of human gait was developed conjointly with another 2-D model of a robotic orthosis capable of actuating hip, knee and ankle joints simultaneously. The musculoskeletal model consists of eight major muscle groups namely; soleus (SOL), gastrocnemius (GAS), tibialis anterior (TA), hamstrings (HAM), vasti (VAS), gluteus maximus (GLU), uniarticular hip flexors (iliopsoas, IP), and Rectus Femoris (RF). BWS was provided at levels of 0, 20, 40 and 60% during the simulations. In order to obtain a feasible set of muscle activities during subsequent gait cycles, an inverse dynamics algorithm along with a quadratic minimization algorithm was implemented. The dynamic parameters of the robot assisted human gait such as joint angle trajectories, ground contact force (GCF), human limb joint torques and robot induced torques at different levels of BWS were derived. The patterns of muscle activities at variable BWS were derived and analysed. For most part of the gait cycle (GC) the muscle activation patterns are quite similar for all levels of BWS as is apparent from the mean of muscle activities for the complete GC. Effect of BWS variation during robot assisted gait on muscle activities was studied by developing dynamic simulation. It is expected that the proposed dynamic simulation approach will provide important inferences and information about the muscle function variations consequent upon a change in BWS during robot assisted gait. This information shall be quite important while investigating the influence of BWS intonation on neuromuscular parameters of interest during robotic gait training.
A human quadrupedal gait following poliomyelitis: From the Dercum-Muybridge collaboration (1885).
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.
NASA Astrophysics Data System (ADS)
Bohra, Murtaza
Legged rovers are often considered as viable solutions for traversing unknown terrain. This work addresses the optimal locomotion reconfigurability of quadruped rovers, which consists of obtaining optimal locomotion modes, and transitioning between them. A 2D sagittal plane rover model is considered based on a domestic cat. Using a Genetic Algorithm, the gait, pose and control variables that minimize torque or maximize speed are found separately. The optimization approach takes into account the elimination of leg impact, while considering the entire variable spectrum. The optimal solutions are consistent with other works on gait optimization, and are similar to gaits found in quadruped animals as well. An online model-free gait planning framework is also implemented, that is based on Central Pattern Generators is implemented. It is used to generate joint and control trajectories for any arbitrarily varying speed profile, and shown to regulate locomotion transition and speed modulation, both endogenously and continuously.
Chen, Gong; Qi, Peng; Guo, Zhao; Yu, Haoyong
2017-06-01
In the field of gait rehabilitation robotics, achieving human-robot synchronization is very important. In this paper, a novel human-robot synchronization method using gait event information is proposed. This method includes two steps. First, seven gait events in one gait cycle are detected in real time with a hidden Markov model; second, an adaptive oscillator is utilized to estimate the stride percentage of human gait using any one of the gait events. Synchronous reference trajectories for the robot are then generated with the estimated stride percentage. This method is based on a bioinspired adaptive oscillator, which is a mathematical tool, first proposed to explain the phenomenon of synchronous flashing among fireflies. The proposed synchronization method is implemented in a portable knee-ankle-foot robot and tested in 15 healthy subjects. This method has the advantages of simple structure, flexible selection of gait events, and fast adaptation. Gait event is the only information needed, and hence the performance of synchronization holds when an abnormal gait pattern is involved. The results of the experiments reveal that our approach is efficient in achieving human-robot synchronization and feasible for rehabilitation robotics application.
Robotic gait trainer in water: development of an underwater gait-training orthosis.
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.
Neurologic Correlates of Gait Abnormalities in Cerebral Palsy: Implications for Treatment
Zhou, Joanne; Butler, Erin E.; Rose, Jessica
2017-01-01
Cerebral palsy (CP) is the most common movement disorder in children. A diagnosis of CP is often made based on abnormal muscle tone or posture, a delay in reaching motor milestones, or the presence of gait abnormalities in young children. Neuroimaging of high-risk neonates and of children diagnosed with CP have identified patterns of neurologic injury associated with CP, however, the neural underpinnings of common gait abnormalities remain largely uncharacterized. Here, we review the nature of the brain injury in CP, as well as the neuromuscular deficits and subsequent gait abnormalities common among children with CP. We first discuss brain injury in terms of mechanism, pattern, and time of injury during the prenatal, perinatal, or postnatal period in preterm and term-born children. Second, we outline neuromuscular deficits of CP with a focus on spastic CP, characterized by muscle weakness, shortened muscle-tendon unit, spasticity, and impaired selective motor control, on both a microscopic and functional level. Third, we examine the influence of neuromuscular deficits on gait abnormalities in CP, while considering emerging information on neural correlates of gait abnormalities and the implications for strategic treatment. This review of the neural basis of gait abnormalities in CP discusses what is known about links between the location and extent of brain injury and the type and severity of CP, in relation to the associated neuromuscular deficits, and subsequent gait abnormalities. Targeted treatment opportunities are identified that may improve functional outcomes for children with CP. By providing this context on the neural basis of gait abnormalities in CP, we hope to highlight areas of further research that can reduce the long-term, debilitating effects of CP. PMID:28367118
Vickers, Joshua; Reed, Austin; Decker, Robert; Conrad, Bryan P; Olegario-Nebel, Marissa; Vincent, Heather K
2017-03-01
Despite the ubiquity of gait assessment in clinic and research, it is unclear how observation impacts gait, particularly in persons with chronic pain and psychological stress. We compared temporal spatial gait patterns in people with and without chronic low back pain (CLBP) when they were aware and unaware of being observed. This was a repeated-measures, deception study in 55 healthy persons (32.0±12.4 yr, 24.2±2.7kg/m 2 ) and persons with CLBP (51.9±17.9 yr, 27.8±4.4kg/m 2 ). Participants performed one condition in which they were unaware of observation (UNW), and three conditions under investigator observation: (1) aware of observation (AWA), (2) investigators watching cadence, (3) investigators watching step length. Participants walked across an 8.4m gait mat, while temporal spatial parameters of gait were collected. The Medical Outcomes Short Form (SF-12), Beck Depression Inventory (BDI), State Trait Anxiety Inventory (STAI), and Oswestry Disability Index (ODI) were completed. Significant condition by group interactions were found for velocity and step length (p<0.05). Main effects of study condition existed for all gait variables except for step width. Main effects of group (healthy, LBP) were significant for all variables except for step width (p<0.05). Regression analyses revealed that after accounting for age, sex, and SF-12 mental component score, BDI scores predict velocity changes during walking from the UNW to AWA conditions. These findings show that people change their gait patterns when being observed. Gait analyses may require additional trials before data can reliably be interpreted and used for clinical decision-making. Copyright © 2017 Elsevier B.V. All rights reserved.
Assistive devices alter gait patterns in Parkinson disease: advantages of the four-wheeled walker.
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.
Ground reaction forces and plantar pressure distribution during occasional loaded gait.
Castro, Marcelo; Abreu, Sofia; Sousa, Helena; Machado, Leandro; Santos, Rubim; Vilas-Boas, João Paulo
2013-05-01
This study compared the ground reaction forces (GRF) and plantar pressures between unloaded and occasional loaded gait. The GRF and plantar pressures of 60 participants were recorded during unloaded gait and occasional loaded gait (wearing a backpack that raised their body mass index to 30); this load criterion was adopted because is considered potentially harmful in permanent loaded gait (obese people). The results indicate an overall increase (absolute values) of GRF and plantar pressures during occasional loaded gait (p < 0.05); also, higher normalized (by total weight) values in the medial midfoot and toes, and lower values in the lateral rearfoot region were observed. During loaded gait the magnitude of the vertical GRF (impact and thrust maximum) decreased and the shear forces increased more than did the proportion of the load (normalized values). These data suggest a different pattern of GRF and plantar pressure distribution during occasional loaded compared to unloaded gait. Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.
Evaluation and management of crouch gait.
Kedem, Paz; Scher, David M
2016-02-01
Crouch gait is defined as excessive ankle dorsiflexion, knee and hip flexion during the stance phase. This gait disorder is common among patients with cerebral palsy. The present article brings an up-to-date literature review on the pathoanatomy, natural history, and treatment of this frequent gait abnormality. Hamstrings are often not shortened in patients with crouch. Patella alta must be addressed if surgery is performed. Surgical correction of joint contractures and lever arm dysfunction can be effectively achieved through a single-event multilevel surgery. Crouch gait is a common gait deviation, often seen among ambulatory diplegic and quadriplegic patients, once they reach the pubertal spurt, when weak muscles can no longer support a toe walking pattern because of rapidly increased weight. This form of gait is highly ineffective and might compromise walking ability over time. The anterior knee is overloaded; pain, extensor mechanism failure, and arthritis might develop. Its progressive nature often requires surgical intervention. The cause of crouch gait is multifactorial, and surgery should be tailored to meet the individual's specific anatomic and physiologic abnormalities.
Gait of dairy cows on floors with different slipperiness.
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 coefficient of friction, but the effect of pattern was better detected by skid-resistance measurements. Consequently, several physical characteristics are needed to objectively describe the slip resistance of cattle floors. Soft rubber mats gave better tracking than hard, solid floors, even with a grooved surface or a tamped pattern. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Galey, Scott A; Lerner, Zachary F; Bulea, Thomas C; Zimbler, Seymour; Damiano, Diane L
2017-05-01
Cerebral palsy (CP) is a prevalent group of neuromotor disorders caused by early injury to brain regions or pathways that control movement. Patients with CP exhibit a range of functional motor disabilities and pathologic gait patterns. Crouch gait, characterized by increased knee flexion throughout stance, is a common gait pattern in CP that increases energy costs of walking and contributes to ambulatory decline. Our aim was to perform the first systematic literature review on the effectiveness of interventions utilized to ameliorate crouch gait in CP. Comprehensive searches of five medical databases yielded 38 papers with 30 focused on orthopaedic management. Evidence supports the use of initial hamstring lengthenings and rectus femoris transfers, where indicated, for improving objective gait measures with limited data on improving gait speed or gross motor function. In contrast, evidence argues against hamstring transfers and revision hamstring lengthening, with recent interest in more technically demanding corrective procedures. Only eight studies evaluated alternatives to surgery, specifically strength training, botulinum toxin or orthoses, with inconsistent and/or short-lived results. Although crouch in CP is recognized clinically as a complex multi-joint, multi-planar gait disorder, this review largely failed to identify interventions beyond those which directly address sagittal plane knee motion, indicating a major knowledge gap. Quality of existing data was notably weak, with few studies properly controlled or adequately sized. Outcomes from specific procedures are confounded by multilevel surgeries. Successful longer term strategies to prevent worsening of crouch and subsequent functional decline are needed. Systematic review. Copyright © 2017. Published by Elsevier B.V.
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. PMID:25705672
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.
An accelerometry-based comparison of 2 robotic assistive devices for treadmill training of gait.
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.
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.
Scrunching: a novel escape gait in planarians
NASA Astrophysics Data System (ADS)
Cochet-Escartin, Olivier; Mickolajczyk, Keith J.; Collins, Eva-Maria S.
2015-10-01
The ability to escape a predator or other life-threatening situations is central to animal survival. Different species have evolved unique strategies under anatomical and environmental constraints. In this study, we describe a novel musculature-driven escape gait in planarians, ‘scrunching’, which is quantitatively different from other planarian gaits, such as gliding and peristalsis. We show that scrunching is a conserved gait among different flatworm species, underlying its importance as an escape mechanism. We further demonstrate that it can be induced by a variety of physical stimuli, including amputation, high temperature, electric shock and low pH. We discuss the functional basis for scrunching as the preferential gait when gliding is impaired due to a disruption of mucus production. Finally, we show that the key mechanical features of scrunching are adequately captured by a simple biomechanical model that is solely based on experimental data from traction force microscopy and tissue rheology without fit parameters. Together, our results form a complete description of this novel form of planarian locomotion. Because scrunching has distinct dynamics, this gait can serve as a robust behavioral readout for studies of motor neuron and muscular functions in planarians and in particular the restoration of these functions during regeneration.
Lee, Byoung-Hee
2016-04-01
[Purpose] This study investigated the effects of real-time feedback using infrared camera recognition technology-based augmented reality in gait training for children with cerebral palsy. [Subjects] Two subjects with cerebral palsy were recruited. [Methods] In this study, augmented reality based real-time feedback training was conducted for the subjects in two 30-minute sessions per week for four weeks. Spatiotemporal gait parameters were used to measure the effect of augmented reality-based real-time feedback training. [Results] Velocity, cadence, bilateral step and stride length, and functional ambulation improved after the intervention in both cases. [Conclusion] Although additional follow-up studies of the augmented reality based real-time feedback training are required, the results of this study demonstrate that it improved the gait ability of two children with cerebral palsy. These findings suggest a variety of applications of conservative therapeutic methods which require future clinical trials.
Pau, Massimiliano; Corona, Federica; Coghe, Giancarlo; Marongiu, Elisabetta; Loi, Andrea; Crisafulli, Antonio; Concu, Alberto; Galli, Manuela; Marrosu, Maria Giovanna; Cocco, Eleonora
2018-01-01
The purpose of this study is to quantitatively assess the effect of 6 months of supervised adapted physical activity (APA i.e. physical activity designed for people with special needs) on spatio-temporal and kinematic parameters of gait in persons with Multiple Sclerosis (pwMS). Twenty-two pwMS with Expanded Disability Status Scale scores ranging from 1.5 to 5.5 were randomly assigned either to the intervention group (APA, n = 11) or the control group (CG, n = 11). The former underwent 6 months of APA consisting of 3 weekly 60-min sessions of aerobic and strength training, while CG participants were engaged in no structured PA program. Gait patterns were analyzed before and after the training using three-dimensional gait analysis by calculating spatio-temporal parameters and concise indexes of gait kinematics (Gait Profile Score - GPS and Gait Variable Score - GVS) as well as dynamic Range of Motion (ROM) of hip, knee, and ankle joints. The training originated significant improvements in stride length, gait speed and cadence in the APA group, while GPS and GVS scores remained practically unchanged. A trend of improvement was also observed as regard the dynamic ROM of hip, knee, and ankle joints. No significant changes were observed in the CG for any of the parameters considered. The quantitative analysis of gait supplied mixed evidence about the actual impact of 6 months of APA on pwMS. Although some improvements have been observed, the substantial constancy of kinematic patterns of gait suggests that the full transferability of the administered training on the ambulation function may require more specific exercises. Implications for rehabilitation Adapted Physical Activity (APA) is effective in improving spatio-temporal parameters of gait, but not kinematics, in people with multiple sclerosis. Dynamic range of motion during gait is increased after APA. The full transferability of APA on the ambulation function may require specific exercises rather than generic lower limbs strength/flexibility training.
Design of a gait training device for control of pelvic obliquity.
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.
Beretta, Elena; Romei, Marianna; Molteni, Erika; Avantaggiato, Paolo; Strazzer, Sandra
2015-01-01
To evaluate the combined effect of robotic-aided gait training (RAGT) and physical therapy (PT) on functional abilities and gait pattern in children and adolescents exiting acquired brain injury (ABI), through functional clinical scales and 3D-Gait Analysis (GA). A group of 23 patients with ABI underwent 20 sessions of RAGT in addition to traditional manual PT. All the patients were evaluated before and after the training by using the Gross Motor Function Measures (GMFM) and the Functional Assessment Questionnaire. Ambulant children were also evaluated through the 6 Minutes Walk Test (6MinWT) and GA. Finally, results were compared with those obtained from a control group of ABI children who underwent PT only. After the training, the GMFM showed significant improvement in both dimensions 'D' (standing) and 'E' (walking). In ambulant patients the 6MinWT showed significant improvement after training and GA highlighted a significant increase in cadence, velocity and stride length. Moreover, hip kinematics on the sagittal plane revealed a statistically significant increase in range of motion (ROM) during the whole gait cycle, increased hip extension during terminal stance and increased ROM during the swing phase. The data suggest that the combined programme RAGT + PT induces improvements in functional activities and gait pattern in children and adolescents with ABI and demonstrated it to be an elective tool for the maintenance of the patients' full compliance throughout the rehabilitative programme.
Gait outcome following outpatient physiotherapy based on the Bobath concept in people post stroke.
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.
Joint Angular Velocity in Spastic Gait and the Influence of Muscle-Tendon Lengthening*
GRANATA, KEVIN P.; ABEL, MARK F.; DAMIANO, DIANE L.
2006-01-01
Background Joint angular velocity (the rate of flexion and extension of a joint) is related to the dynamics of muscle activation and force generation during walking. Therefore, the goal of this research was to examine the joint angular velocity in normal and spastic gait and changes resulting from muscle-tendon lengthening (recession and tenotomy) in patients who have spastic cerebral palsy. Methods The gait patterns of forty patients who had been diagnosed with spastic cerebral palsy (mean age, 8.3 years; range, 3.7 to 14.8 years) and of seventy-three age-matched, normally developing subjects were evaluated with three-dimensional motion analysis and electromyography. The patients who had cerebral palsy were evaluated before muscle-tendon lengthening and nine months after treatment. Results The gait patterns of the patients who had cerebral palsy were characterized by increased flexion of the knee in the stance phase, premature plantar flexion of the ankle, and reduced joint angular velocities compared with the patterns of the normally developing subjects. Even though muscle-tendon lengthening altered sagittal joint angles in gait, the joint angular velocities were generally unchanged at the hip and knee. Only the ankle demonstrated modified angular velocities, including reduced dorsiflexion velocity at foot-strike and improved dorsiflexion velocity through midstance, after treatment. Electromyographic changes included reduced amplitude of the gastrocnemius-soleus during the loading phase and decreased knee coactivity (the ratio of quadriceps and hamstring activation) at toe-off. Principal component analyses showed that, compared with joint-angle data, joint angular velocity was better able to discriminate between the gait patterns of the normal and cerebral palsy groups. Conclusions This study showed that muscle-tendon lengthening corrects biomechanical alignment as reflected by changes in sagittal joint angles. However, joint angular velocity and electromyographic data suggest that the underlying neural input remains largely unchanged at the hip and knee. Conversely, electromyographic changes and changes in velocity in the ankle indicate that the activation pattern of the gastrocnemius-soleus complex in response to stretch was altered by recession of the complex. PMID:10682726
Scott-Pandorf, Melissa M; O'Connor, Daniel P; Layne, Charles S; Josić, Kresimir; Kurz, Max J
2009-09-01
With human exploration of the moon and Mars on the horizon, research considerations for space suit redesign have surfaced. The portable life support system (PLSS) used in conjunction with the space suit during the Apollo missions may have influenced the dynamic balance of the gait pattern. This investigation explored potential issues with the PLSS design that may arise during the Mars exploration. A better understanding of how the location of the PLSS load influences the dynamic stability of the gait pattern may provide insight, such that space missions may have more productive missions with a smaller risk of injury and damaging equipment while falling. We explored the influence the PLSS load position had on the dynamic stability of the walking pattern. While walking, participants wore a device built to simulate possible PLSS load configurations. Floquet and Lyapunov analysis techniques were used to quantify the dynamic stability of the gait pattern. The dynamic stability of the gait pattern was influenced by the position of load. PLSS loads that are placed high and forward on the torso resulted in less dynamically stable walking patterns than loads placed evenly and low on the torso. Furthermore, the kinematic results demonstrated that all joints of the lower extremity may be important for adjusting to different load placements and maintaining dynamic stability. Space scientists and engineers may want to consider PLSS designs that distribute loads evenly and low, and space suit designs that will not limit the sagittal plane range of motion at the lower extremity joints.
Gait patterns for crime fighting: statistical evaluation
NASA Astrophysics Data System (ADS)
Sulovská, Kateřina; Bělašková, Silvie; Adámek, Milan
2013-10-01
The criminality is omnipresent during the human history. Modern technology brings novel opportunities for identification of a perpetrator. One of these opportunities is an analysis of video recordings, which may be taken during the crime itself or before/after the crime. The video analysis can be classed as identification analyses, respectively identification of a person via externals. The bipedal locomotion focuses on human movement on the basis of their anatomical-physiological features. Nowadays, the human gait is tested by many laboratories to learn whether the identification via bipedal locomotion is possible or not. The aim of our study is to use 2D components out of 3D data from the VICON Mocap system for deep statistical analyses. This paper introduces recent results of a fundamental study focused on various gait patterns during different conditions. The study contains data from 12 participants. Curves obtained from these measurements were sorted, averaged and statistically tested to estimate the stability and distinctiveness of this biometrics. Results show satisfactory distinctness of some chosen points, while some do not embody significant difference. However, results presented in this paper are of initial phase of further deeper and more exacting analyses of gait patterns under different conditions.
Ferrari, Alberto; Ginis, Pieter; Hardegger, Michael; Casamassima, Filippo; Rocchi, Laura; Chiari, Lorenzo
2016-07-01
Gait impairments are among the most disabling symptoms in several musculoskeletal and neurological conditions, severely limiting personal autonomy. Wearable gait sensors have been attracting attention as diagnostic tool for gait and are emerging as promising tool for tutoring and guiding gait execution. If their popularity is continuously growing, still there is room for improvement, especially towards more accurate solutions for spatio-temporal gait parameters estimation. We present an implementation of a zero-velocity-update gait analysis system based on a Kalman filter and off-the-shelf shoe-worn inertial sensors. The algorithms for gait events and step length estimation were specifically designed to comply with pathological gait patterns. More so, an Android app was deployed to support fully wearable and stand-alone real-time gait analysis. Twelve healthy subjects were enrolled to preliminarily tune the algorithms; afterwards sixteen persons with Parkinson's disease were enrolled for a validation study. Over the 1314 strides collected on patients at three different speeds, the total root mean square difference on step length estimation between this system and a gold standard was 2.9%. This shows that the proposed method allows for an accurate gait analysis and paves the way to a new generation of mobile devices usable anywhere for monitoring and intervention.
Astephen Wilson, J L; Deluzio, K J; Dunbar, M J; Caldwell, G E; Hubley-Kozey, C L
2011-02-01
The objective of this study was to determine the association between biomechanical and neuromuscular factors of clinically diagnosed mild to moderate knee osteoarthritis (OA) with radiographic severity and pain severity separately. Three-dimensional gait analysis and electromyography were performed on a group of 40 participants with clinically diagnosed mild to moderate medial knee OA. Associations between radiographic severity, defined using a visual analog radiographic score, and pain severity, defined with the pain subscale of the WOMAC osteoarthritis index, with knee joint kinematics and kinetics, electromyography patterns of periarticular knee muscles, BMI and gait speed were determined with correlation analyses. Multiple linear regression analyses of radiographic and pain severity were also explored. Statistically significant correlations between radiographic severity and the overall magnitude of the knee adduction moment during stance (r²=21.4%, P=0.003) and the magnitude of the knee flexion angle during the gait cycle (r²=11.4%, P=0.03) were found. Significant correlations between pain and gait speed (r²=28.2%, P<0.0001), the activation patterns of the lateral gastrocnemius (r²=16.6%, P=0.009) and the medial hamstring (r²=10.3%, P=0.04) during gait were found. The combination of the magnitude of the knee adduction moment during stance and BMI explained a significant portion of the variability in radiographic severity (R(2)=27.1%, P<0.0001). No multivariate model explained pain severity better than gait speed alone. This study suggests that some knee joint biomechanical variables are associated with structural knee OA severity measured from radiographs in clinically diagnosed mild to moderate levels of disease, but that pain severity is only reflected in gait speed and neuromuscular activation patterns. A combination of the knee adduction moment and BMI better explained structural knee OA severity than any individual factor alone. Copyright © 2010 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.
Dynamic Simulation and Analysis of Human Walking Mechanism
NASA Astrophysics Data System (ADS)
Azahari, Athirah; Siswanto, W. A.; Ngali, M. Z.; Salleh, S. Md.; Yusup, Eliza M.
2017-01-01
Behaviour such as gait or posture may affect a person with the physiological condition during daily activities. The characteristic of human gait cycle phase is one of the important parameter which used to described the human movement whether it is in normal gait or abnormal gait. This research investigates four types of crouch walking (upright, interpolated, crouched and severe) by simulation approach. The assessment are conducting by looking the parameters of hamstring muscle joint, knee joint and ankle joint. The analysis results show that based on gait analysis approach, the crouch walking have a weak pattern of walking and postures. Short hamstring and knee joint is the most influence factor contributing to the crouch walking due to excessive hip flexion that typically accompanies knee flexion.
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 robust, and to be in agreement with the current gold standard (i.e., manual calibration performed by an expert engineer). The use of a graphical user interface is a promising tool for the effective use of an automatic procedure in a clinical context. PMID:29615890
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 robust, and to be in agreement with the current gold standard (i.e., manual calibration performed by an expert engineer). The use of a graphical user interface is a promising tool for the effective use of an automatic procedure in a clinical context.
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 < 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.
Tiidus, Peter M.; Pierrynowski, Michael; Dawson, Kimberley A.
2002-01-01
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 < 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. PMID:24748843
Vismara, Luca; Romei, Marianna; Galli, Manuela; Montesano, Angelo; Baccalaro, Gabriele; Crivellini, Marcello; Grugni, Graziano
2007-05-10
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. 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. 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. 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.
Sacheli, Lucia Maria; Zapparoli, Laura; De Santis, Carlo; Preti, Matteo; Pelosi, Catia; Ursino, Nicola; Zerbi, Alberto; Banfi, Giuseppe; Paulesu, Eraldo
2017-10-01
Gait imagery and gait observation can boost the recovery of locomotion dysfunctions; yet, a neurologically justified rationale for their clinical application is lacking as much as a direct comparison of their neural correlates. Using functional magnetic resonance imaging, we measured the neural correlates of explicit motor imagery of gait during observation of in-motion videos shot in a park with a steady cam (Virtual Walking task). In a 2 × 2 factorial design, we assessed the modulatory effect of gait observation and of foot movement execution on the neural correlates of the Virtual Walking task: in half of the trials, the participants were asked to mentally imitate a human model shown while walking along the same route (mental imitation condition); moreover, for half of all the trials, the participants also performed rhythmic ankle dorsiflexion as a proxy for stepping movements. We found that, beyond the areas associated with the execution of lower limb movements (the paracentral lobule, the supplementary motor area, and the cerebellum), gait imagery also recruited dorsal premotor and posterior parietal areas known to contribute to the adaptation of walking patterns to environmental cues. When compared with mental imitation, motor imagery recruited a more extensive network, including a brainstem area compatible with the human mesencephalic locomotor region (MLR). Reduced activation of the MLR in mental imitation indicates that this more visually guided task poses less demand on subcortical structures crucial for internally generated gait patterns. This finding may explain why patients with subcortical degeneration benefit from rehabilitation protocols based on gait observation. Hum Brain Mapp 38:5195-5216, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
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 effects of increased weight during pre–post measurements to avoid misinterpretation of treatment results. Overweight and obesity in CP should be counteracted or prevented as the increased weight has detrimental effects on the gait pattern. PMID:28123360
Control of human gait stability through foot placement.
Bruijn, Sjoerd M; van Dieën, Jaap H
2018-06-01
During human walking, the centre of mass (CoM) is outside the base of support for most of the time, which poses a challenge to stabilizing the gait pattern. Nevertheless, most of us are able to walk without substantial problems. In this review, we aim to provide an integrative overview of how humans cope with an underactuated gait pattern. A central idea that emerges from the literature is that foot placement is crucial in maintaining a stable gait pattern. In this review, we explore this idea; we first describe mechanical models and concepts that have been used to predict how foot placement can be used to control gait stability. These concepts, such as for instance the extrapolated CoM concept, the foot placement estimator concept and the capture point concept, provide explicit predictions on where to place the foot relative to the body at each step, such that gait is stabilized. Next, we describe empirical findings on foot placement during human gait in unperturbed and perturbed conditions. We conclude that humans show behaviour that is largely in accordance with the aforementioned concepts, with foot placement being actively coordinated to body CoM kinematics during the preceding step. In this section, we also address the requirements for such control in terms of the sensory information and the motor strategies that can implement such control, as well as the parts of the central nervous system that may be involved. We show that visual, vestibular and proprioceptive information contribute to estimation of the state of the CoM. Foot placement is adjusted to variations in CoM state mainly by modulation of hip abductor muscle activity during the swing phase of gait, and this process appears to be under spinal and supraspinal, including cortical, control. We conclude with a description of how control of foot placement can be impaired in humans, using ageing as a primary example and with some reference to pathology, and we address alternative strategies available to stabilize gait, which include modulation of ankle moments in the stance leg and changes in body angular momentum, such as rapid trunk tilts. Finally, for future research, we believe that especially the integration of consideration of environmental constraints on foot placement with balance control deserves attention. © 2018 The Authors.
The impact of Nordic walking training on the gait of the elderly.
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.
IMU-Based Gait Recognition Using Convolutional Neural Networks and Multi-Sensor Fusion.
Dehzangi, Omid; Taherisadr, Mojtaba; ChangalVala, Raghvendar
2017-11-27
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 identification task. Based on our experimental results, 91% subject identification accuracy was achieved using the best individual IMU and 2DTF-DCNN. We then investigated our proposed early and late sensor fusion approaches, which improved the gait identification accuracy of the system to 93.36% and 97.06%, respectively.
NASA Technical Reports Server (NTRS)
1984-01-01
L & M Electronics, Inc.'s telemetry system is used to measure degree and location of abnormal muscle activity. This telemetry was originally used to monitor astronauts vital functions. Leg sensors send wireless signals to computer which develops pictures of gait patterns. System records, measures and analyzes muscle activities in limbs and spine. Computer developed pictures of gait patterns help physicians determine potential of corrective surgery, evaluate various types of braces, or decide whether physical therapy may improve motor functions.
Quantifying Parkinson's disease progression by simulating gait patterns
NASA Astrophysics Data System (ADS)
Cárdenas, Luisa; Martínez, Fabio; Atehortúa, Angélica; Romero, Eduardo
2015-12-01
Modern rehabilitation protocols of most neurodegenerative diseases, in particular the Parkinson Disease, rely on a clinical analysis of gait patterns. Currently, such analysis is highly dependent on both the examiner expertise and the type of evaluation. Development of evaluation methods with objective measures is then crucial. Physical models arise as a powerful alternative to quantify movement patterns and to emulate the progression and performance of specific treatments. This work introduces a novel quantification of the Parkinson disease progression using a physical model that accurately represents the main gait biomarker, the body Center of Gravity (CoG). The model tracks the whole gait cycle by a coupled double inverted pendulum that emulates the leg swinging for the single support phase and by a damper-spring System (SDP) that recreates both legs in contact with the ground for the double phase. The patterns generated by the proposed model are compared with actual ones learned from 24 subjects in stages 2,3, and 4. The evaluation performed demonstrates a better performance of the proposed model when compared with a baseline model(SP) composed of a coupled double pendulum and a mass-spring system. The Frechet distance measured differences between model estimations and real trajectories, showing for stages 2, 3 and 4 distances of 0.137, 0.155, 0.38 for the baseline and 0.07, 0.09, 0.29 for the proposed method.
Effects of Indoor Footwear on Balance and Gait Patterns in Community-Dwelling Older Women.
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.
Self-Organizing Map With Time-Varying Structure to Plan and Control Artificial Locomotion.
Araujo, Aluizio F R; Santana, Orivaldo V
2015-08-01
This paper presents an algorithm, self-organizing map-state trajectory generator (SOM-STG), to plan and control legged robot locomotion. The SOM-STG is based on an SOM with a time-varying structure characterized by constructing autonomously close-state trajectories from an arbitrary number of robot postures. Each trajectory represents a cyclical movement of the limbs of an animal. The SOM-STG was designed to possess important features of a central pattern generator, such as rhythmic pattern generation, synchronization between limbs, and swapping between gaits following a single command. The acquisition of data for SOM-STG is based on learning by demonstration in which the data are obtained from different demonstrator agents. The SOM-STG can construct one or more gaits for a simulated robot with six legs, can control the robot with any of the gaits learned, and can smoothly swap gaits. In addition, SOM-STG can learn to construct a state trajectory form observing an animal in locomotion. In this paper, a dog is the demonstrator agent.
Gait Planning and Stability Control of a Quadruped Robot
Li, Junmin; Wang, Jinge; Yang, Simon X.; Zhou, Kedong; Tang, Huijuan
2016-01-01
In order to realize smooth gait planning and stability control of a quadruped robot, a new controller algorithm based on CPG-ZMP (central pattern generator-zero moment point) is put forward in this paper. To generate smooth gait and shorten the adjusting time of the model oscillation system, a new CPG model controller and its gait switching strategy based on Wilson-Cowan model are presented in the paper. The control signals of knee-hip joints are obtained by the improved multi-DOF reduced order control theory. To realize stability control, the adaptive speed adjustment and gait switch are completed by the real-time computing of ZMP. Experiment results show that the quadruped robot's gaits are efficiently generated and the gait switch is smooth in the CPG control algorithm. Meanwhile, the stability of robot's movement is improved greatly with the CPG-ZMP algorithm. The algorithm in this paper has good practicability, which lays a foundation for the production of the robot prototype. PMID:27143959
Gait Planning and Stability Control of a Quadruped Robot.
Li, Junmin; Wang, Jinge; Yang, Simon X; Zhou, Kedong; Tang, Huijuan
2016-01-01
In order to realize smooth gait planning and stability control of a quadruped robot, a new controller algorithm based on CPG-ZMP (central pattern generator-zero moment point) is put forward in this paper. To generate smooth gait and shorten the adjusting time of the model oscillation system, a new CPG model controller and its gait switching strategy based on Wilson-Cowan model are presented in the paper. The control signals of knee-hip joints are obtained by the improved multi-DOF reduced order control theory. To realize stability control, the adaptive speed adjustment and gait switch are completed by the real-time computing of ZMP. Experiment results show that the quadruped robot's gaits are efficiently generated and the gait switch is smooth in the CPG control algorithm. Meanwhile, the stability of robot's movement is improved greatly with the CPG-ZMP algorithm. The algorithm in this paper has good practicability, which lays a foundation for the production of the robot prototype.
Jarchi, Delaram; Lo, Benny; Wong, Charence; Ieong, Edmund; Nathwani, Dinesh; Yang, Guang-Zhong
2016-08-01
Objective assessment of detailed gait patterns after orthopaedic surgery is important for post-surgical follow-up and rehabilitation. The purpose of this paper is to assess the use of a single ear-worn sensor for clinical gait analysis. A reliability measure is devised for indicating the confidence level of the estimated gait events, allowing it to be used in free-walking environments and for facilitating clinical assessment of orthopaedic patients after surgery. Patient groups prior to or following anterior cruciate ligament (ACL) reconstruction and knee replacement were recruited to assess the proposed method. The ability of the sensor for detailed longitudinal analysis is demonstrated with a group of patients after lower limb reconstruction by considering parameters such as temporal and force-related gait asymmetry derived from gait events. The results suggest that the ear-worn sensor can be used for objective gait assessments of orthopaedic patients without the requirement and expense of an elaborate laboratory setup for gait analysis. It significantly simplifies the monitoring protocol and opens the possibilities for home-based remote patient assessment.
Hinton, Dorelle Clare; Cheng, Yeu-Yao; Paquette, Caroline
2018-01-01
With increasing numbers of adults owning a cell phone, walking while texting has become common in daily life. Previous research has shown that walking is not entirely automated and when challenged with a secondary task, normal walking patterns are disrupted. This study investigated the effects of texting on the walking patterns of healthy young adults while walking on a split-belt treadmill. Following full adaptation to the split-belt treadmill, thirteen healthy adults (23±3years) walked on a tied-belt and split-belt treadmill, both with and without a simultaneous texting task. Inertial-based movement monitors recorded spatiotemporal components of gait and stability. Measures of spatial and temporal gait symmetry were calculated to compare gait patterns between treadmill (tied-belt and split-belt) and between texting (absent or present) conditions. Typing speed and accuracy were recorded to monitor texting performance. Similar to previous research, the split-belt treadmill caused an alteration to both spatial and temporal aspects of gait, but not to time spent in dual support or stability. However, all participants successfully maintained balance while walking and were able to perform the texting task with no significant change to accuracy or speed on either treadmill. From this paradigm it is evident that when university students are challenged to text while walking on either a tied-belt or split-belt treadmill, without any other distraction, their gait is minimally affected and they are able to maintain texting performance. Copyright © 2017 Elsevier B.V. All rights reserved.
Self-esteem recognition based on gait pattern using Kinect.
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 (p<0.001). We divide the participants according to gender, and for males, the correlation coefficient is 0.43 (p<0.001), for females, it is 0.59 (p<0.001). Using gait data captured by Kinect sensor, we find that the gait pattern could be used to recognize self-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.
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.
Dynamics of the vortex wakes of flying and swimming vertebrates.
Rayner, J M
1995-01-01
The vortex wakes of flying and swimming animals provide evidence of the history of aero- and hydrodynamic force generation during the locomotor cycle. Vortex-induced momentum flux in the wake is the reaction of forces the animal imposes on its environment, which must be in equilibrium with inertial and external forces. In flying birds and bats, the flapping wings generate lift both to provide thrust and to support the weight. Distinct wingbeat and wake movement patterns can be identified as gaits. In flow visualization experiments, only two wake patterns have been identified: a vortex ring gait with inactive upstroke, and a continuous vortex gait with active upstroke. These gaits may be modelled theoretically by free vortex and lifting line theory to predict mechanical energy consumption, aerodynamic forces and muscle activity. Longer-winged birds undergo a distinct gait change with speed, but shorter-winged species use the vortex ring gait at all speeds. In swimming fish, the situation is more complex: the wake vortices form a reversed von Kármán vortex street, but little is known about the mechanism of generation of the wake, or about how it varies with speed and acceleration or with body form and swimming mode. An unresolved complicating factor is the interaction between the drag wake of the flapping fish body and the thrusting wake from the tail.
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.
Effects on proprioception by Kinesio taping of the knee after anterior cruciate ligament rupture.
Bischoff, Lars; Babisch, Christian; Babisch, Jürgen; Layher, Frank; Sander, Klaus; Matziolis, Georg; Pietsch, Stefan; Röhner, Eric
2018-03-10
The use of Kinesio tape (KT) to improve proprioception is a matter of considerable debate. In comparison, the rupture of the anterior cruciate ligament is a sufficiently well-investigated injury with a proven compromise of proprioception. The objective of the present study was to assess a supportive effect on proprioception after KT application, taking the anterior cruciate ligament (ACL) rupture as an example. Forty-eight patients who had suffered an ACL rupture, confirmed clinically and by magnetic resonance imaging, and who were treated conservatively or were awaiting surgery were included in this study. In all patients, a gait analysis was performed on the affected leg before and after KT application. In addition, the IKDC score, the Lysholm score, stability using the Rolimeter, and the angle reproduction test were determined. Thirty-nine men and nine women who had had an ACL rupture for at least 3 weeks were included in the study. Significant improvements were achieved on the affected knee joint for the gait analysis parameters touchdown and unrolling, cadence, stability and stance phase as well as an extension of the hip joint. The Lysholm score improved from 79.3 to 85.8 (p < 0.001) and the IKDC score from 60.2 to 71.3 points (p < 0.001). Significant improvements were achieved in the Rolimeter and angle reproduction test. The use of KT has a positive effect on proprioception in patients with an anterior cruciate ligament rupture. Therefore, the application may improve gait pattern as well as the subjective function of the affected knee joint.
Yeung, Ling-Fung; Ockenfeld, Corinna; Pang, Man-Kit; Wai, Hon-Wah; Soo, Oi-Yan; Li, Sheung-Wai; Tong, Kai-Yu
2018-06-19
Robot-assisted ankle-foot-orthosis (AFO) can provide immediate powered ankle assistance in post-stroke gait training. Our research team has developed a novel lightweight portable robot-assisted AFO which is capable of detecting walking intentions using sensor feedback of wearer's gait pattern. This study aims to investigate the therapeutic effects of robot-assisted gait training with ankle dorsiflexion assistance. This was a double-blinded randomized controlled trial. Nineteen chronic stroke patients with motor impairment at ankle participated in 20-session robot-assisted gait training for about five weeks, with 30-min over-ground walking and stair ambulation practices. Robot-assisted AFO either provided active powered ankle assistance during swing phase in Robotic Group (n = 9), or torque impedance at ankle joint as passive AFO in Sham Group (n = 10). Functional assessments were performed before and after the 20-session gait training with 3-month Follow-up. Primary outcome measure was gait independency assessed by Functional Ambulatory Category (FAC). Secondary outcome measures were clinical scores including Fugl-Meyer Assessment (FMA), Modified Ashworth Scale (MAS), Berg Balance Scale (BBS), Timed 10-Meter Walk Test (10MWT), Six-minute Walk Test (SMWT), supplemented by gait analysis. All outcome measures were performed in unassisted gait after patients had taken off the robot-assisted AFO. Repeated-measures analysis of covariance was conducted to test the group differences referenced to clinical scores before training. After 20-session robot-assisted gait training with ankle dorsiflexion assistance, the active ankle assistance in Robotic Group induced changes in gait pattern with improved gait independency (all patients FAC ≥ 5 post-training and 3-month follow-up), motor recovery, walking speed, and greater confidence in affected side loading response (vertical ground reaction force + 1.49 N/kg, peak braking force + 0.24 N/kg) with heel strike instead of flat foot touch-down at initial contact (foot tilting + 1.91°). Sham Group reported reduction in affected leg range of motion (ankle dorsiflexion - 2.36° and knee flexion - 8.48°) during swing. Robot-assisted gait training with ankle dorsiflexion assistance could improve gait independency and help stroke patients developing confidence in weight acceptance, but future development of robot-assisted AFO should consider more lightweight and custom-fit design. ClinicalTrials.gov NCT02471248 . Registered 15 June 2015 retrospectively registered.
Martín-Gonzalo, Juan Andrés; Rodríguez-Andonaegui, Irene; López-López, Javier; Pascual-Pascual, Samuel Ignacio
2018-01-01
The Hereditary Spastic Paraplegias (HSP) are a group of heterogeneous disorders with a wide spectrum of underlying neural pathology, and hence HSP patients express a variety of gait abnormalities. Classification of these phenotypes may help in monitoring disease progression and personalizing therapies. This is currently managed by measuring values of some kinematic and spatio-temporal parameters at certain moments during the gait cycle, either in the doctor´s surgery room or after very precise measurements produced by instrumental gait analysis (IGA). These methods, however, do not provide information about the whole structure of the gait cycle. Classification of the similarities among time series of IGA measured values of sagittal joint positions throughout the whole gait cycle can be achieved by hierarchical clustering analysis based on multivariate dynamic time warping (DTW). Random forests can estimate which are the most important isolated parameters to predict the classification revealed by DTW, since clinicians need to refer to them in their daily practice. We acquired time series of pelvic, hip, knee, ankle and forefoot sagittal angular positions from 26 HSP and 33 healthy children with an optokinetic IGA system. DTW revealed six gait patterns with different degrees of impairment of walking speed, cadence and gait cycle distribution and related with patient’s age, sex, GMFCS stage, concurrence of polyneuropathy and abnormal visual evoked potentials or corpus callosum. The most important parameters to differentiate patterns were mean pelvic tilt and hip flexion at initial contact. Longer time of support, decreased values of hip extension and increased knee flexion at initial contact can differentiate the mildest, near to normal HSP gait phenotype and the normal healthy one. Increased values of knee flexion at initial contact and delayed peak of knee flexion are important factors to distinguish GMFCS stages I from II-III and concurrence of polyneuropathy. PMID:29518090
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.
Schülein, Samuel; Barth, Jens; Rampp, Alexander; Rupprecht, Roland; Eskofier, Björn M; Winkler, Jürgen; Gaßmann, Karl-Günter; Klucken, Jochen
2017-02-27
In an increasing aging society, reduced mobility is one of the most important factors limiting activities of daily living and overall quality of life. The ability to walk independently contributes to the mobility, but is increasingly restricted by numerous diseases that impair gait and balance. The aim of this cross-sectional observation study was to examine whether spatio-temporal gait parameters derived from mobile instrumented gait analysis can be used to measure the gait stabilizing effects of a wheeled walker (WW) and whether these gait parameters may serve as surrogate marker in hospitalized patients with multifactorial gait and balance impairment. One hundred six patients (ages 68-95) wearing inertial sensor equipped shoes passed an instrumented walkway with and without gait support from a WW. The walkway assessed the risk of falling associated gait parameters velocity, swing time, stride length, stride time- and double support time variability. Inertial sensor-equipped shoes measured heel strike and toe off angles, and foot clearance. The use of a WW improved the risk of spatio-temporal parameters velocity, swing time, stride length and the sagittal plane associated parameters heel strike and toe off angles in all patients. First-time users (FTUs) showed similar gait parameter improvement patterns as frequent WW users (FUs). However, FUs with higher levels of gait impairment improved more in velocity, stride length and toe off angle compared to the FTUs. The impact of a WW can be quantified objectively by instrumented gait assessment. Thus, objective gait parameters may serve as surrogate markers for the use of walking aids in patients with gait and balance impairments.
Quadrupedal rodent gait compensations in a low dose monoiodoacetate model of osteoarthritis.
Lakes, Emily H; Allen, Kyle D
2018-06-01
Rodent gait analysis provides robust, quantitative results for preclinical musculoskeletal and neurological models. In prior work, surgical models of osteoarthritis have been found to result in a hind limb shuffle-stepping gait compensation, while a high dose monoiodoacetate (MIA, 3 mg) model resulted in a hind limb antalgic gait. However, it is unknown whether the antalgic gait caused by MIA is associated with severity of degeneration from the high dosage or the whole-joint degeneration associated with glycolysis inhibition. This study evaluates rodent gait changes resulting from a low dose, 1 mg unilateral intra-articular injection of MIA compared to saline injected and naïve rats. Spatiotemporal and dynamic gait parameters were collected from a total of 42 male Lewis rats spread across 3 time points: 1, 2, and 4 weeks post-injection. To provide a detailed analysis of this low dose MIA model, gait analysis was used to uniquely quantify both fore and hind limb gait parameters. Our data indicate that 1 mg of MIA caused relatively minor degeneration and a shuffle-step gait compensation, similar to the compensation observed in prior surgical models. These data from a 1 mg MIA model show a different gait compensation compared to a previously studied 3 mg model. This 1 mg MIA model resulted in gait compensations more similar to a previously studied surgical model of osteoarthritis. Additionally, this study provides detailed 4 limb analysis of rodent gait that includes spatiotemporal and dynamic data from the same gait trial. These data highlight the importance of measuring dynamic data in combination with spatiotemporal data, since compensatory gait patterns may not be captured by spatial, temporal, or dynamic characterizations alone. Copyright © 2018 Elsevier B.V. All rights reserved.
Kim, Kyoung; Lee, Dong-Kyu; Jung, Sang-In
2015-01-01
[Purpose] To investigate the effect of coordination movement using the Proprioceptive Neuromuscular Facilitation pattern underwater on the balance and gait of stroke patients. [Subjects and Methods] Twenty stroke patients were randomly assigned to an experimental group that performed coordination movement using the Proprioceptive Neuromuscular Facilitation pattern underwater and a control group (n =10 each). Both the groups underwent neurodevelopmental treatment, and the experimental group performed coordination movement using the Proprioceptive neuromuscular facilitation pattern underwater. Balance was measured using the Berg Balance Scale and Functional Reach Test, and gait was measured using the 10-Meter Walk Test and Timed Up and Go Test. To compare in-group data before and after the intervention, paired t-test was used. Independent t-test was used to compare differences in the results of the Berg Balance Scale, Functional Reach Test, 10-Meter Walk Test, and Timed Up and Go Test before and after the intervention between the groups. [Results] Comparison within the groups showed significant differences in the results of the Berg Balance Scale, Functional Reach Test, 10-Meter Walk Test, and Timed Up and Go Test before and after the experimental intervention. On comparison between the groups, there were greater improvements in the scores of the Berg Balance Scale, Functional Reach Test, 10-Meter Walk Test, and Timed Up and Go Test in the experimental group. [Conclusion] The findings demonstrate that coordination movement using the Proprioceptive Neuromuscular Facilitation pattern under water has a significant effect on the balance and gait of stroke patients. PMID:26834335
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.
New insights into turbulent pedestrian movement pattern in crowd-quakes
NASA Astrophysics Data System (ADS)
Ma, J.; Song, W. G.; Lo, S. M.; Fang, Z. M.
2013-02-01
Video recordings right before the Love Parade disaster have been quantitatively analyzed to explore the bursts of unusual crowd movement patterns, crowd-quakes. The pedestrian movement pattern in this incident was special for the reason that it happened in a congested counter flow scenario, where stopped pedestrians were involved. No one was believed to have pushed others intentionally at the beginning, however, under this situation, the body contacts among the pedestrians still induced a force spread, which then led to velocity fluctuation. As indicated by the individual velocity-related features, the densely crowded pedestrian movement displayed turbulent flow features. Further analyzing the overall flow field, we also found that the pedestrian flow field shared typical patterns with turbulent fluid flow. As a result of the turbulent state, different clusters of pedestrians displayed different velocity features. Thus crowd pressure which took into account the velocity and density information was proved to be a good indicator of crowd disasters. Based on these essential features of pedestrian crowd-quakes, a minimal model, i.e., a pedestrian crowd-quake model, was established. Effects including pedestrian gait, stress conservation level and personal intention to escape were explored.
Lee, Byoung-Hee
2016-01-01
[Purpose] This study investigated the effects of real-time feedback using infrared camera recognition technology-based augmented reality in gait training for children with cerebral palsy. [Subjects] Two subjects with cerebral palsy were recruited. [Methods] In this study, augmented reality based real-time feedback training was conducted for the subjects in two 30-minute sessions per week for four weeks. Spatiotemporal gait parameters were used to measure the effect of augmented reality-based real-time feedback training. [Results] Velocity, cadence, bilateral step and stride length, and functional ambulation improved after the intervention in both cases. [Conclusion] Although additional follow-up studies of the augmented reality based real-time feedback training are required, the results of this study demonstrate that it improved the gait ability of two children with cerebral palsy. These findings suggest a variety of applications of conservative therapeutic methods which require future clinical trials. PMID:27190489
2011-01-01
Background Fatigue is a frequent and serious symptom in patients with Multiple Sclerosis (MS). However, to date there are only few methods for the objective assessment of fatigue. The aim of this study was to develop a method for the objective assessment of motor fatigue using kinematic gait analysis based on treadmill walking and an infrared-guided system. Patients and methods Fourteen patients with clinically definite MS participated in this study. Fatigue was defined according to the Fatigue Scale for Motor and Cognition (FSMC). Patients underwent a physical exertion test involving walking at their pre-determined patient-specific preferred walking speed until they reached complete exhaustion. Gait was recorded using a video camera, a three line-scanning camera system with 11 infrared sensors. Step length, width and height, maximum circumduction with the right and left leg, maximum knee flexion angle of the right and left leg, and trunk sway were measured and compared using paired t-tests (α = 0.005). In addition, variability in these parameters during one-minute intervals was examined. The fatigue index was defined as the number of significant mean and SD changes from the beginning to the end of the exertion test relative to the total number of gait kinematic parameters. Results Clearly, for some patients the mean gait parameters were more affected than the variability of their movements while other patients had smaller differences in mean gait parameters with greater increases in variability. Finally, for other patients gait changes with physical exertion manifested both in changes in mean gait parameters and in altered variability. The variability and fatigue indices correlated significantly with the motoric but not with the cognitive dimension of the FSMC score (R = -0.602 and R = -0.592, respectively; P < 0.026). Conclusions Changes in gait patterns following a physical exertion test in patients with MS suffering from motor fatigue can be measured objectively. These changes in gait patterns can be described using the motor fatigue index and represent an objective measure to assess motor fatigue in MS patients. The results of this study have important implications for the assessments and treatment evaluations of fatigue in MS. PMID:22029427
Feldman, Anatol G; Krasovsky, Tal; Baniña, Melanie C; Lamontagne, Anouk; Levin, Mindy F
2011-04-01
Locomotion is presumably guided by feed-forward shifts in the referent body location in the desired direction in the environment. We propose that the difference between the actual and the referent body locations is transmitted to neurons that virtually diminish this difference by appropriately changing the referent body configuration, i.e. the body posture at which muscles reach their recruitment thresholds. Muscles are activated depending on the gap between the actual and the referent body configurations resulting in a step being made to minimize this gap. This hypothesis implies that the actual and the referent leg configurations can match each other at certain phases of the gait cycle, resulting in minimization of leg muscle activity. We found several leg configurations at which EMG minima occurred, both during forward and backward gait. It was also found that the set of limb configurations associated with EMG minima can be changed by modifying the pattern of forward and backward gait. Our hypothesis predicts that, in response to perturbations of gait, the rate of shifts in the referent body location can temporarily be changed to avoid falling. The rate influences the phase of rhythmic limb movements during gait. Therefore, following the change in the rate of the referent body location, the whole gait pattern, for all four limbs, will irreversibly be shifted in time (long-lasting and global phase resetting) with only transient changes in the gait speed, swing and stance timing and cycle duration. Aside from transient changes in the duration of the swing and/or stance phase in response to perturbation, few previous studies have documented long-lasting and global phase resetting of human gait in response to perturbation. Such resetting was a robust finding in our study. By confirming the notion that feed-forward changes in the referent body location and configuration underlie human locomotion, this study solves the classical problem in the relationship between stability of posture and gait and advances the understanding of how human locomotion involves the whole body and is accomplished in a spatial frame of reference associated with the environment.
Influence of artificial shock absorbers on human gait.
Voloshin, A; Wosk, J
1981-10-01
The effect of artificial shock absorbers on the human gait and the technique for its quantitative evaluation have been studied. The results obtained have shown that viscoelastic inserts reduced the amplitude of the incoming shock waves bearing upon the musculoskeletal system as a result of the heel strike, by 42 percent (mean value). Conservative treatment, using such inserts for patients with different clinical symptoms of degenerative joint diseases, has shown excellent results. Seventy-eight percent of the clinical symptoms disappeared, while satisfactory improvement was reported in 17 percent of the subjects.
Neuromuscular adjustments of gait associated with unstable conditions
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
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 < .05). Furthermore, women showed 15% to 35% increased variability in all of these gait parameters during the dual-task trial compared with men (all P < .01). In the present cohort, 70-year-old 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 Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.
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 Transplantation and Wiley Periodicals, Inc.
Gait mode recognition and control for a portable-powered ankle-foot orthosis.
David Li, Yifan; Hsiao-Wecksler, Elizabeth T
2013-06-01
Ankle foot orthoses (AFOs) are widely used as assistive/rehabilitation devices to correct the gait of people with lower leg neuromuscular dysfunction and muscle weakness. We have developed a portable powered ankle-foot orthosis (PPAFO), which uses a pneumatic bi-directional rotary actuator powered by compressed CO2 to provide untethered dorsiflexor and plantarflexor assistance at the ankle joint. Since portability is a key to the success of the PPAFO as an assist device, it is critical to recognize and control for gait modes (i.e. level walking, stair ascent/descent). While manual mode switching is implemented in most powered orthotic/prosthetic device control algorithms, we propose an automatic gait mode recognition scheme by tracking the 3D position of the PPAFO from an inertial measurement unit (IMU). The control scheme was designed to match the torque profile of physiological gait data during different gait modes. Experimental results indicate that, with an optimized threshold, the controller was able to identify the position, orientation and gait mode in real time, and properly control the actuation. It was also illustrated that during stair descent, a mode-specific actuation control scheme could better restore gait kinematic and kinetic patterns, compared to using the level ground controller.
Computational evaluation of load carriage effects on gait balance stability.
Mummolo, Carlotta; Park, Sukyung; Mangialardi, Luigi; Kim, Joo H
2016-01-01
Evaluating the effects of load carriage on gait balance stability is important in various applications. However, their quantification has not been rigorously addressed in the current literature, partially due to the lack of relevant computational indices. The novel Dynamic Gait Measure (DGM) characterizes gait balance stability by quantifying the relative effects of inertia in terms of zero-moment point, ground projection of center of mass, and time-varying foot support region. In this study, the DGM is formulated in terms of the gait parameters that explicitly reflect the gait strategy of a given walking pattern and is used for computational evaluation of the distinct balance stability of loaded walking. The observed gait adaptations caused by load carriage (decreased single support duration, inertia effects, and step length) result in decreased DGM values (p < 0.0001), which indicate that loaded walking motions are more statically stable compared with the unloaded normal walking. Comparison of the DGM with other common gait stability indices (the maximum Floquet multiplier and the margin of stability) validates the unique characterization capability of the DGM, which is consistently informative of the presence of the added load.
NASA Astrophysics Data System (ADS)
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.
Adair, Brooke; Rodda, Jillian; McGinley, Jennifer L; Graham, H Kerr; Morris, Meg E
2016-08-01
To examine the kinematic gait deviations at the trunk and pelvis of children with hereditary spastic paraplegia (HSP). This exploratory observational study quantified gait kinematics for the trunk and pelvis from 11 children with HSP (7 males, 4 females) using the Gait Profile Score and Gait Variable Scores (GVS), and compared the kinematics to data from children with typical development using a Mann-Whitney U test. Children with HSP (median age 11y 4mo, interquartile range 4y) demonstrated large deviations in the GVS for the trunk and pelvis in the sagittal and coronal planes when compared to the gait patterns of children with typical development (p=0.010-0.020). Specific deviations included increased range of movement for the trunk in the coronal plane and increased excursion of the trunk and pelvis in the sagittal plane. In the transverse plane, children with HSP demonstrated later peaks in posterior pelvic rotation. The kinematic gait deviations identified in this study raise questions about the contribution of muscle weakness in HSP. Further research is warranted to determine contributing factors for gait dysfunction in HSP, especially the relative influence of spasticity and weakness. © 2016 Mac Keith Press.
Herbin, Marc; Hommet, Eva; Hanotin-Dossot, Vicky; Perret, Martine; Hackert, Rémi
2018-06-01
The gaits of the adult grey mouse lemur Microcebus murinus were studied during treadmill locomotion over a large range of velocities. The locomotion sequences were analysed to determine the gait and the various spatiotemporal gait parameters of the limbs. We found that velocity adjustments are accounted for differently by stride frequency and stride length depending on whether the animal showed a symmetrical or an asymmetrical gait. When using symmetrical gaits the increase in velocity is associated with a constant contribution of the stride length and stride frequency; the increase of the stride frequency being always lower. When using asymmetrical gaits, the increase in velocity is mainly assured by an increase in the stride length which tends to decrease with increasing velocity. A reduction in both stance time and swing time contributed to the increase in stride frequency for both gaits, though with a major contribution from the decrease in stance time. The pattern of locomotion obtained in a normal young adult mouse lemurs can be used as a template for studying locomotor control deficits during aging or in different environments such as arboreal ones which likely modify the kinematics of locomotion.
Modelling gait transition in two-legged animals
NASA Astrophysics Data System (ADS)
Pinto, Carla M. A.; Santos, Alexandra P.
2011-12-01
The study of locomotor patterns has been a major research goal in the last decades. Understanding how intralimb and interlimb coordination works out so well in animals' locomotion is a hard and challenging task. Many models have been proposed to model animal's rhythms. These models have also been applied to the control of rhythmic movements of adaptive legged robots, namely biped, quadruped and other designs. In this paper we study gait transition in a central pattern generator (CPG) model for bipeds, the 4-cells model. This model is proposed by Golubitsky, Stewart, Buono and Collins and is studied further by Pinto and Golubitsky. We briefly resume the work done by Pinto and Golubitsky. We compute numerically gait transition in the 4-cells CPG model for bipeds. We use Morris-Lecar equations and Wilson-Cowan equations as the internal dynamics for each cell. We also consider two types of coupling between the cells: diffusive and synaptic. We obtain secondary gaits by bifurcation of primary gaits, by varying the coupling strengths. Nevertheless, some bifurcating branches could not be obtained, emphasizing the fact that despite analytically those bifurcations exist, finding them is a hard task and requires variation of other parameters of the equations. We note that the type of coupling did not influence the results.
Gait re-education based on the Bobath concept in two patients with hemiplegia following stroke.
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.
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.
Compressive tibiofemoral force during crouch gait.
Steele, Katherine M; Demers, Matthew S; Schwartz, Michael H; Delp, Scott L
2012-04-01
Crouch gait, a common walking pattern in individuals with cerebral palsy, is characterized by excessive flexion of the hip and knee. Many subjects with crouch gait experience knee pain, perhaps because of elevated muscle forces and joint loading. The goal of this study was to examine how muscle forces and compressive tibiofemoral force change with the increasing knee flexion associated with crouch gait. Muscle forces and tibiofemoral force were estimated for three unimpaired children and nine children with cerebral palsy who walked with varying degrees of knee flexion. We scaled a generic musculoskeletal model to each subject and used the model to estimate muscle forces and compressive tibiofemoral forces during walking. Mild crouch gait (minimum knee flexion 20-35°) produced a peak compressive tibiofemoral force similar to unimpaired walking; however, severe crouch gait (minimum knee flexion>50°) increased the peak force to greater than 6 times body-weight, more than double the load experienced during unimpaired gait. This increase in compressive tibiofemoral force was primarily due to increases in quadriceps force during crouch gait, which increased quadratically with average stance phase knee flexion (i.e., crouch severity). Increased quadriceps force contributes to larger tibiofemoral and patellofemoral loading which may contribute to knee pain in individuals with crouch gait. Copyright © 2011 Elsevier B.V. All rights reserved.
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.
NASA Astrophysics Data System (ADS)
Oliveira, Miguel; Santos, Cristina P.; Costa, Lino
2012-09-01
In this paper, a study based on sensitivity analysis is performed for a gait multi-objective optimization system that combines bio-inspired Central Patterns Generators (CPGs) and a multi-objective evolutionary algorithm based on NSGA-II. In this system, CPGs are modeled as autonomous differential equations, that generate the necessary limb movement to perform the required walking gait. In order to optimize the walking gait, a multi-objective problem with three conflicting objectives is formulated: maximization of the velocity, the wide stability margin and the behavioral diversity. The experimental results highlight the effectiveness of this multi-objective approach and the importance of the objectives to find different walking gait solutions for the quadruped robot.
Neurological Gait Abnormalities And Risk Of Falls In Older Adults
Verghese, Joe; Ambrose, Anne F; Lipton, Richard B; Wang, Cuiling
2009-01-01
Objective To estimate the validity of neurological gait evaluations in predicting falls in older adults. Methods We studied 632 adults age 70 and over (mean age 80.6 years, 62% women) enrolled in the Einstein Aging Study whose walking patterns were evaluated by study clinicians using a clinical gait rating scale. Association of neurological gaits and six subtypes (hemiparetic, frontal, Parkinsonian, unsteady, neuropathic, and spastic) with incident falls was studied using generalized estimation equation procedures adjusted for potential confounders, and reported as risk ratio with 95% confidence intervals (CI). Results Over a mean follow-up of 21 months, 244 (39%) subjects fell. Mean fall rate was 0.47 falls per person year. At baseline, 120 subjects were diagnosed with neurological gaits. Subjects with neurological gaits were at increased risk of falls (risk ratio 1.49, 95% CI 1.11 – 2.00). Unsteady (risk ratio 1.52, 95% CI 1.04 – 2.22), and neuropathic gait (risk ratio 1.94, 95% CI 1.07 – 3.11) were the two gait subtypes that predicted risk of falls. The results remained significant after accounting for disability and cognitive status, and also with injurious falls as the outcome. Conclusions Neurological gaits and subtypes are independent predictors of falls in older adults. Neurological gait assessments will help clinicians identify and institute preventive measures in older adults at high risk for falls. PMID:19784714
Rucco, Rosaria; Agosti, Valeria; Jacini, Francesca; Sorrentino, Pierpaolo; Varriale, Pasquale; De Stefano, Manuela; Milan, Graziella; Montella, Patrizia; Sorrentino, Giuseppe
2017-02-01
Alzheimer's disease (AD) and behavioral variant of Frontotemporal Dementia (bvFTD) are characterized respectively by atrophy in the medial temporal lobe with memory loss and prefrontal and anterior temporal degeneration with dysexecutive syndrome. In this study, we hypothesized that specific gait patterns are induced by either frontal or temporal degeneration. To test this hypothesis, we studied the gait pattern in bvFTD (23) and AD (22) patients in single and dual task ("motor" and "cognitive") conditions. To detect subtle alterations, we performed motion analysis estimating both spatio-temporal parameters and joint excursions. In the single task condition, the bvFTD group was more unstable and slower compared to healthy subjects, while only two stability parameters were compromised in the AD group. During the motor dual task, both velocity and stability parameters worsened further in the bvFTD group. In the same experimental conditions, AD patients showed a significantly lower speed and stride length than healthy subjects. During the cognitive dual task, a further impairment of velocity and stability parameters was observed in the bvFTD group. Interestingly, during the cognitive dual task, the gait performance of the AD group markedly deteriorated, as documented by the impairment of more indices of velocity and stability. Finally, the kinematic data of thigh, knee, and ankle were more helpful in revealing gait impairment than the spatio-temporal parameters alone. In conclusion, our data showed that the dysexecutive syndrome induces specific gait alterations. Furthermore, our results suggest that the gait worsens in the AD patients when the cognitive resources are stressed. Copyright © 2016 Elsevier B.V. All rights reserved.
Catavitello, Giovanna; Ivanenko, Yuri P.; Lacquaniti, Francesco
2015-01-01
The rich repertoire of locomotor behaviors in quadrupedal animals requires flexible inter-limb and inter-segmental coordination. Here we studied the kinematic coordination of different gaits (walk, trot, gallop, and swim) of six dogs (Canis lupus familiaris) and, in particular, the planar covariation of limb segment elevation angles. The results showed significant variations in the relative duration of rearward limb movement, amplitude of angular motion, and inter-limb coordination, with gait patterns ranging from a lateral sequence of footfalls during walking to a diagonal sequence in swimming. Despite these differences, the planar law of inter-segmental coordination was maintained across different gaits in both forelimbs and hindlimbs. Notably, phase relationships and orientation of the covariation plane were highly limb specific, consistent with the functional differences in their neural control. Factor analysis of published muscle activity data also demonstrated differences in the characteristic timing of basic activation patterns of the forelimbs and hindlimbs. Overall, the results demonstrate that the planar covariation of inter-segmental coordination has emerged for both fore- and hindlimbs and all gaits, although in a limb-specific manner. PMID:26218076
"Gunslinger's gait": a new cause of unilaterally reduced arm swing.
Araújo, Rui; Ferreira, Joaquim J; Antonini, Angelo; Bloem, Bastiaan R
2015-12-14
To postulate a new possible cause of a unilaterally reduced arm swing in addition to the known medical conditions such as shoulder pathology, Erb's palsy, stroke, and Parkinson's disease. Analysis of YouTube videos depicting the gait of highly ranked Russian officials. We found a similar walking pattern in President Vladimir Putin, Prime Minister Dmitry Medvedev and three other highly ranked Russian officials, all presenting with a consistently reduced right arm swing in the absence of other overt neurological abnormalities. We propose that this new gait pattern, which we term "gunslinger's gait," may result from a behavioural adaptation, possibly triggered by KGB or other forms of weapons training where trainees are taught to keep their right hand close to the chest while walking, allowing them to quickly draw a gun when faced with a foe. This should be included in the differential diagnosis of a unilaterally reduced arm swing. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Locomotor Adaptation to an Asymmetric Force on the Human Pelvis Directed Along the Right Leg.
Vashista, Vineet; Martelli, Dario; Agrawal, Sunil
2015-09-11
In this work, we study locomotor adaptation in healthy adults when an asymmetric force vector is applied to the pelvis directed along the right leg. A cable-driven Active Tethered Pelvic Assist Device (A-TPAD) is used to apply an external force on the pelvis, specific to a subject's gait pattern. The force vector is intended to provide external weight bearing during walking and modify the durations of limb supports. The motivation is to use this paradigm to improve weight bearing and stance phase symmetry in individuals with hemiparesis. An experiment with nine healthy subjects was conducted. The results show significant changes in the gait kinematics and kinetics while the healthy subjects developed temporal and spatial asymmetry in gait pattern in response to the applied force vector. This was followed by aftereffects once the applied force vector was removed. The adaptation to the applied force resulted in asymmetry in stance phase timing and lower limb muscle activity. We believe this paradigm, when extended to individuals with hemiparesis, can show improvements in weight bearing capability with positive effects on gait symmetry and walking speed.
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.
A Symmetric Inchworm Nanowalker
NASA Astrophysics Data System (ADS)
Chiang, Yi Herng
Intracellular transport by biological nanowalkers occurs in inchworm (IW) gait as well as hand-over-hand (HOH) gait. Multiple versions of artificial inchworm nanowalkers are also realized and proposed, but all rely on different 'head' and 'tail' to gain a direction. Here we demonstrate an inchworm bipedal nanowalker made of DNA that possesses two identical legs and moves directionally along a linear track under alternating ultraviolet and visible light. The inchworm gait is confirmed by operating the walker on a DNA duplex track that is designed to show a distinctive pattern for inchworm versus hand-over-hand gait. Interestingly, the same walker exhibits stride-controlled direction reversals and IW-to-HOH gait switch when the track is systematically modified for elongated spacing between periodic binding stations for the walker. The IW and HOH regimes altogether present an integrated nanowalker mechanism, which can be used to implement nanowalkers of different gaits and directions with DNA, other biomolecules or synthetic molecules on molecular tracks, optical potentials or even solid-state substrates.
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 < 0.001) and impulse (p < 0.001) decreased six months following arthroplasty, whilst gait in women remained unchanged after surgery. Obesity did not influence gait changes in men or women. Gait of female arthroplasty participants did not differ from female controls after surgery except for sagittal plane knee range of motion (p = 0.003), whilst men differed from controls for peak knee adduction moment (p = 0.011), knee range of motion (p < 0.001), and peak knee flexion moment (p < 0.001). Sex, but not obesity, influenced changes in gait 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.
The Gait Disorder in Downbeat Nystagmus Syndrome
Schniepp, Roman; Wuehr, Max; Huth, Sabrina; Pradhan, Cauchy; Schlick, Cornelia; Brandt, Thomas; Jahn, Klaus
2014-01-01
Background Downbeat nystagmus (DBN) is a common form of acquired fixation nystagmus with key symptoms of oscillopsia and gait disturbance. Gait disturbance could be a result of impaired visual feedback due to the involuntary ocular oscillations. Alternatively, a malfunction of cerebellar locomotor control might be involved, since DBN is considered a vestibulocerebellar disorder. Methods Investigation of walking in 50 DBN patients (age 72±11 years, 23 females) and 50 healthy controls (HS) (age 70±11 years, 23 females) using a pressure sensitive carpet (GAITRite). The patient cohort comprised subjects with only ocular motor signs (DBN) and subjects with an additional limb ataxia (DBNCA). Gait investigation comprised different walking speeds and walking with eyes closed. Results In DBN, gait velocity was reduced (p<0.001) with a reduced stride length (p<0.001), increased base of support (p<0.050), and increased double support (p<0.001). Walking with eyes closed led to significant gait changes in both HS and DBN. These changes were more pronounced in DBN patients (p<0.001). Speed-dependency of gait variability revealed significant differences between the subgroups of DBN and DBNCA (p<0.050). Conclusions (I) Impaired visual control caused by involuntary ocular oscillations cannot sufficiently explain the gait disorder. (II) The gait of patients with DBN is impaired in a speed dependent manner. (III) Analysis of gait variability allows distinguishing DBN from DBNCA: Patients with pure DBN show a speed dependency of gait variability similar to that of patients with afferent vestibular deficits. In DBNCA, gait variability resembles the pattern found in cerebellar ataxia. PMID:25140517
The gait disorder in downbeat nystagmus syndrome.
Schniepp, Roman; Wuehr, Max; Huth, Sabrina; Pradhan, Cauchy; Schlick, Cornelia; Brandt, Thomas; Jahn, Klaus
2014-01-01
Downbeat nystagmus (DBN) is a common form of acquired fixation nystagmus with key symptoms of oscillopsia and gait disturbance. Gait disturbance could be a result of impaired visual feedback due to the involuntary ocular oscillations. Alternatively, a malfunction of cerebellar locomotor control might be involved, since DBN is considered a vestibulocerebellar disorder. Investigation of walking in 50 DBN patients (age 72 ± 11 years, 23 females) and 50 healthy controls (HS) (age 70 ± 11 years, 23 females) using a pressure sensitive carpet (GAITRite). The patient cohort comprised subjects with only ocular motor signs (DBN) and subjects with an additional limb ataxia (DBNCA). Gait investigation comprised different walking speeds and walking with eyes closed. In DBN, gait velocity was reduced (p<0.001) with a reduced stride length (p<0.001), increased base of support (p<0.050), and increased double support (p<0.001). Walking with eyes closed led to significant gait changes in both HS and DBN. These changes were more pronounced in DBN patients (p<0.001). Speed-dependency of gait variability revealed significant differences between the subgroups of DBN and DBNCA (p<0.050). (I) Impaired visual control caused by involuntary ocular oscillations cannot sufficiently explain the gait disorder. (II) The gait of patients with DBN is impaired in a speed dependent manner. (III) Analysis of gait variability allows distinguishing DBN from DBNCA: Patients with pure DBN show a speed dependency of gait variability similar to that of patients with afferent vestibular deficits. In DBNCA, gait variability resembles the pattern found in cerebellar ataxia.
Design of patient-specific gait modifications for knee osteoarthritis rehabilitation.
Fregly, Benjamin J; Reinbolt, Jeffrey A; Rooney, Kelly L; Mitchell, Kim H; Chmielewski, Terese L
2007-09-01
Abstract-Gait modification is a nonsurgical approach for reducing the external knee adduction torque in patients with knee osteoarthritis (OA). The magnitude of the first adduction torque peak in particular is strongly associated with knee OA progression. While toeing out has been shown to reduce the second peak, no clinically realistic gait modifications have been identified that effectively reduce both peaks simultaneously. This study predicts novel patient-specific gait modifications that achieve this goal without changing the foot path. The modified gait motion was designed for a single patient with knee OA using dynamic optimization of a patient-specific, full-body gait model. The cost function minimized the knee adduction torque subject to constraints limiting how much the new gait motion could deviate from the patient's normal gait motion. The optimizations predicted a "medial-thrust" gait pattern that reduced the first adduction torque peak between 32% and 54% and the second peak between 34% and 56%. The new motion involved three synergistic kinematic changes: slightly decreased pelvis obliquity, slightly increased leg flexion, and slightly increased pelvis axial rotation. After gait retraining, the patient achieved adduction torque reductions of 39% to 50% in the first peak and 37% to 55% in the second one. These reductions are comparable to those reported after high tibial osteotomy surgery. The associated kinematic changes were consistent with the predictions except for pelvis obliquity, which showed little change. This study demonstrates that it is feasible to design novel patient-specific gait modifications with potential clinical benefit using dynamic optimization of patient-specific, full-body gait models. Further investigation is needed to assess the extent to which similar gait modifications may be effective for other patients with knee OA.
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.
Effects of walking speed on asymmetry and bilateral coordination of gait
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 (p<0.001). Stepwise regression revealed that slowed gait 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
Singh, Harshvardhan; Sanders, Ozell; McCombe Waller, Sandy; Bair, Woei-Nan; Beamer, Brock; Creath, Robert A; Rogers, Mark W
2017-10-01
To determine and compare gait speed during head-forward and side-to-side head-turn walking in individuals with lower versus greater lateral balance. Cross-sectional study. University research laboratory. Older adults (N=93; 42 men, 51 women; mean age ± SD, 73 ± 6.08y) who could walk independently. (1) Balance tolerance limit (BTL), defined as the lowest perturbation intensity where a multistep balance recovery pattern was first evoked in response to randomized lateral waist-pull perturbations of standing balance to the left and right sides, at 6 different intensities (range from level 2: 4.5-cm displacement at 180cm/s 2 acceleration, to level 7: 22.5-cm displacement at 900cm/s 2 acceleration); (2) gait speed, determined using an instrumented gait mat; (3) balance, evaluated with the Activities-specific Balance Confidence Scale; and (4) mobility, determined with the Timed Up and Go (TUG). Individuals with low versus high BTL had a slower self-selected head-forward gait speed and head-turn gait speed (P=.002 and P<.001, respectively); the magnitude of difference was greater in head-turn gait speed than head-forward gait speed (Cohen's d=1.0 vs 0.6). Head-turn gait speed best predicted BTL. BTL was moderately and positively related (P=.003) to the ABC Scale and negatively related (P=.017) to TUG. Head-turn gait speed is affected to a greater extent than head-forward gait speed in older individuals with poorer lateral balance and at greater risk of falls. Moreover, head-turn gait speed can be used to assess the interactions of limitations in lateral balance function and gait speed in relation to fall risk in older adults. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Gait characteristics of post-poliomyelitis patients: standardization of quantitative data reporting.
Portnoy, S; Schwartz, I
2013-10-01
To evaluate the differences in gait characteristics and gait symmetry of post-polio syndrome (PPS) patients ambulating with or without shoes and between subgroups walking with different walking aids and orthoses, study the correlation of these data with personal data, illness condition, physical health, frequency of using aids and orthotics and frequency of falls, and derive recommendations for standardization of reporting these data. Twenty-six PPS subjects ambulated with their own walking devices. We calculated spatio-temporal parameters and symmetry indices (SI) of gait using a data acquired by a motion capture system. We compared inter-subject differences in gait pattern for PPS groups that differed by questionnaire-obtained data of demographics, physical activity, polio history, falls and walking aids. Additional inter-subject comparisons were performed between normal subjects (n=16), PPS patients walking with shoes with/without an ankle-foot-orthosis (n=11), PPS patients walking with knee-ankle-foot-orthosis (n=5), and PPS patients walking with a walker/crutches (n=10). We also compared intra-subject variability in PPS subjects who were able to repeat the trials barefoot. Our main results show that subjects who reported participating in physical activity twice a week or more had significantly better step time and double support symmetry. Subjects who use walking aids on a daily basis had significantly higher gait cadence and shorter stride time. Also, subjects that do not require knee-ankle-foot orthoses and/or walking aids walked with a smaller base width and better symmetry in stance and swing durations than PPS subjects who require these aids. The gait pattern of PPS patients is related to numerous intrinsic and extrinsic factors. Standardization of the reporting protocol of gait-related data of PPS patients is crucial for patient evaluation and treatment design. Copyright © 2013 Elsevier Masson SAS. All rights reserved.
Vismara, Luca; Romei, Marianna; Galli, Manuela; Montesano, Angelo; Baccalaro, Gabriele; Crivellini, Marcello; Grugni, Graziano
2007-01-01
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. PMID:17493259
Plummer, Prudence; Eskes, Gail; Wallace, Sarah; Giuffrida, Clare; Fraas, Michael; Campbell, Grace; Clifton, Kerrylee; Skidmore, Elizabeth R
2013-12-01
Cognitive-motor interference (CMI) is evident when simultaneous performance of a cognitive task and a motor task results in deterioration in performance in one or both of the tasks, relative to performance of each task separately. The purpose of this review is to present a framework for categorizing patterns of CMI and to examine the specific patterns of CMI evident in published studies comparing single-task and dual-task performance of cognitive and motor tasks during gait and balance activities after stroke. We also examine the literature for associations between patterns of CMI and a history of falls, as well as evidence for the effects of rehabilitation on CMI after stroke. Overall, this review suggests that during gait activities with an added cognitive task, people with stroke are likely to demonstrate significant decrements in motor performance only (cognitive-related motor interference), or decrements in both motor and cognitive performance (mutual interference). In contrast, patterns of CMI were variable among studies examining balance activities. Comparing people poststroke with and without a history of falls, patterns and magnitude of CMI were similar for fallers and nonfallers. Longitudinal studies suggest that conventional rehabilitation has minimal effects on CMI during gait or balance activities. However, early-phase pilot studies suggest that dual-task interventions may reduce CMI during gait performance in community-dwelling stroke survivors. It is our hope that this innovative and critical examination of the existing literature will highlight the limitations in current experimental designs and inform improvements in the design and reporting of dual-task studies in stroke. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
A generalized locomotion CPG architecture based on oscillatory building blocks.
Yang, Zhijun; França, Felipe M G
2003-07-01
Neural oscillation is one of the most extensively investigated topics of artificial neural networks. Scientific approaches to the functionalities of both natural and artificial intelligences are strongly related to mechanisms underlying oscillatory activities. This paper concerns itself with the assumption of the existence of central pattern generators (CPGs), which are the plausible neural architectures with oscillatory capabilities, and presents a discrete and generalized approach to the functionality of locomotor CPGs of legged animals. Based on scheduling by multiple edge reversal (SMER), a primitive and deterministic distributed algorithm, it is shown how oscillatory building block (OBB) modules can be created and, hence, how OBB-based networks can be formulated as asymmetric Hopfield-like neural networks for the generation of complex coordinated rhythmic patterns observed among pairs of biological motor neurons working during different gait patterns. It is also shown that the resulting Hopfield-like network possesses the property of reproducing the whole spectrum of different gaits intrinsic to the target locomotor CPGs. Although the new approach is not restricted to the understanding of the neurolocomotor system of any particular animal, hexapodal and quadrupedal gait patterns are chosen as illustrations given the wide interest expressed by the ongoing research in the area.
Effects of Corrective Taping on Balance and Gait in Patients With Hallux Valgus.
Gur, Gozde; Ozkal, Ozden; Dilek, Burcu; Aksoy, Songul; Bek, Nilgun; Yakut, Yavuz
2017-05-01
Taping is an effective temporary therapy for improving hallux valgus (HV) in adults. Although HV has been demonstrated to impair postural balance, there is a lack of information about how corrective taping affects balance and gait patterns in adults with HV deformity. Eighteen middle-aged female patients (average age, 53.5 years) with HV were included. Corrective tape was applied to correct HV angulation. A series of balance and gait stability tests were performed before applying tape and 1 hour after the tape was applied with a Balance Master computerized posturography device. The study involved the following tests: modified clinical test of sensory interaction and balance (mCTSIB), unilateral stance (US), limit of stability (LoS), step up/over (SUO), and walk across (WA) tests. No significant difference was found between the no-tape and taped condition in the static balance mCTSIB and US tests ( P > .05). The taping intervention resulted in significant improvement in the dynamic balance measures for the LoS test's backward reaction time and left maximum excursion ( P < .05), a significantly higher impact index bilaterally in the SUO assessment ( P < .05), and an increase in step width mean and variability in the WA test ( P < .05). Taping for correcting HV angulation had negative acute effects on dynamic balance in the SUO and WA tests and positive effects in the LoS test. Corrective taping, although a form of conservative treatment for hallux valgus, has been insufficiently studied in terms of effects on balance. Our results show that taping, as an acute effect, may impair balance in middle-aged adults when walking or ascending and descending stairs.
Quadruped Robot Locomotion using a Global Optimization Stochastic Algorithm
NASA Astrophysics Data System (ADS)
Oliveira, Miguel; Santos, Cristina; Costa, Lino; Ferreira, Manuel
2011-09-01
The problem of tuning nonlinear dynamical systems parameters, such that the attained results are considered good ones, is a relevant one. This article describes the development of a gait optimization system that allows a fast but stable robot quadruped crawl gait. We combine bio-inspired Central Patterns Generators (CPGs) and Genetic Algorithms (GA). CPGs are modelled as autonomous differential equations, that generate the necessar y limb movement to perform the required walking gait. The GA finds parameterizations of the CPGs parameters which attain good gaits in terms of speed, vibration and stability. Moreover, two constraint handling techniques based on tournament selection and repairing mechanism are embedded in the GA to solve the proposed constrained optimization problem and make the search more efficient. The experimental results, performed on a simulated Aibo robot, demonstrate that our approach allows low vibration with a high velocity and wide stability margin for a quadruped slow crawl gait.
Gravel, P; Tremblay, M; Leblond, H; Rossignol, S; de Guise, J A
2010-07-15
A computer-aided method for the tracking of morphological markers in fluoroscopic images of a rat walking on a treadmill is presented and validated. The markers correspond to bone articulations in a hind leg and are used to define the hip, knee, ankle and metatarsophalangeal joints. The method allows a user to identify, using a computer mouse, about 20% of the marker positions in a video and interpolate their trajectories from frame-to-frame. This results in a seven-fold speed improvement in detecting markers. This also eliminates confusion problems due to legs crossing and blurred images. The video images are corrected for geometric distortions from the X-ray camera, wavelet denoised, to preserve the sharpness of minute bone structures, and contrast enhanced. From those images, the marker positions across video frames are extracted, corrected for rat "solid body" motions on the treadmill, and used to compute the positional and angular gait patterns. Robust Bootstrap estimates of those gait patterns and their prediction and confidence bands are finally generated. The gait patterns are invaluable tools to study the locomotion of healthy animals or the complex process of locomotion recovery in animals with injuries. The method could, in principle, be adapted to analyze the locomotion of other animals as long as a fluoroscopic imager and a treadmill are available. Copyright 2010 Elsevier B.V. All rights reserved.
Gait consistency over a 7-day interval in people with Parkinson's disease.
Urquhart, D M; Morris, M E; Iansek, R
1999-06-01
To evaluate the consistency of temporal and spatial parameters of the walking pattern in subjects with idiopathic Parkinson's disease (PD) over a 7-day interval during the "on" phase of the levodopa medication cycle. Walking patterns were measured on a 12-meter walkway at the Kingston Gait Laboratory, Cheltenham, using a computerized stride analyzer. Sixteen subjects (7 women, 9 men) with PD recruited from the Movement Disorders Clinic at Kingston Centre. Speed of walking, stride length, cadence, and the percentage of the walking cycle spent in the double limb support phase of gait were measured, together with the level of disability as indexed by the modified Webster scale. Product-moment correlation coefficients and intraclass correlation coefficients (ICC 2,1) for repeat measures over a 7-day interval were high for speed (r = .90; ICC = .93), cadence (r = .90; ICC = .86), and stride length (r = 1.00; ICC = .97) and moderate for double limb support duration after removal of outliers (r = .75; ICC = .73); 95% confidence intervals for the change scores were within clinically acceptable limits for all variables. The mean modified Webster score was 11.4 on the first day and 10.1 7 days later. The gait pattern and level of disability in subjects with PD without severe motor fluctuations remained stable over a 1-week period when optimal medication prevailed.
Control of impact loading during distracted running before and after gait retraining in runners.
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 < 0.007; Cohen's d > 0.68). Visual feedback after gait retraining reduced PPA and vertical loading rates during distracted running (P < 0.033; Cohen's d > 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.
Gaudreault, Nathaly; Gravel, Denis; Nadeau, Sylvie; Houde, Sylvie; Gagnon, Denis
2010-07-01
3D analysis of the gait of children with Duchenne muscular dystrophy (DMD) was the topic of only a few studies and none of these considered the effect of gait velocity on the gait parameters of children with DMD. Gait parameters of 11 children with DMD were compared to those of 14 control children while considering the effect of gait velocity using 3D biomechanical analysis. Kinematic and kinetic gait parameters were measured using an Optotrak motion analysis system and AMTI force plates embedded in the floor. The data profiles of children with DMD walking at natural gait velocity were compared to those of the control children who walked at both natural and slow gait velocities. When both groups walked at similar velocity, children with DMD had higher cadence and shorter step length. They demonstrated a lower hip extension moment as well as a minimal or absent knee extension moment. At the ankle, a dorsiflexion moment was absent at heel strike due to the anterior location of the center of pressure. The magnitude of the medio-lateral ground reaction force was higher in children with DMD. Despite this increase, the hip abductor moment was lower. Hip power generation was also observed at the mid-stance in DMD children. These results suggest that most of the modifications observed are strategies used by children with DMD to cope with possible muscle weakness in order to provide support, propulsion and balance of the body during gait. Copyright © 2010 Elsevier B.V. All rights reserved.
Imaging: what can it tell us about parkinsonian gait?
Bohnen, Nicolaas I.; Jahn, Klaus
2013-01-01
Functional neuroimaging has provided new tools to study cerebral gait control in Parkinson disease (PD). First, imaging of blood flow functions has identified a supraspinal locomotor network that includes the (frontal) cortex, basal ganglia, brainstem tegmentum and the cerebellum. These studies emphasize also the cognitive and attentional dependency of gait in PD. Furthermore, gait in PD and related syndromes like progressive supranuclear palsy may be associated with dysfunction of the indirect, modulatory prefrontal–subthalamic–pedunculopontine loop of locomotor control. The direct, stereotyped locomotor loop from the primary motor cortex to the spinal cord with rhythmic cerebellar input appears preserved and may contribute to the unflexible gait pattern in parkinsonian gait. Second, neurotransmitter and proteinopathy imaging studies are beginning to unravel novel mechanisms of parkinsonian gait and postural disturbances. Dopamine displacement imaging studies have shown evidence for a mesofrontal dopaminergic shift from a depleted striatum in parkinsonian gait. This may place additional burden on other brain systems mediating attention functions to perform previously automatic motor tasks. For example, our preliminary cholinergic imaging studies suggest significant slowing of gait speed when additional forebrain cholinergic denervation occurs in PD. Cholinergic denervation of the pedunculopontine nucleus and its thalamic projections have been associated with falls and impaired postural control. Deposition of β-amyloid may represent another non-dopaminergic correlate of gait disturbance in PD. These findings illustrate the emergence of dopamine non-responsive gait problems to reflect the transition from a predominantly hypodopaminergic disorder to a multisystem neurodegenerative disorder involving non-dopaminergic locomotor network structures and pathologies. PMID:24132837
MacAulay, Rebecca K; Wagner, Mark T; Szeles, Dana; Milano, Nicholas J
2017-07-01
Longitudinal research indicates that cognitive load dual-task gait assessment is predictive of cognitive decline and thus might provide a sensitive measure to screen for mild cognitive impairment (MCI). However, research among older adults being clinically evaluated for cognitive concerns, a defining feature of MCI, is lacking. The present study investigated the effect of performing a cognitive task on normal walking speed in patients presenting to a memory clinic with cognitive complaints. Sixty-one patients with a mean age of 68 years underwent comprehensive neuropsychological testing, clinical interview, and gait speed (simple- and dual-task conditions) assessments. Thirty-four of the 61 patients met criteria for MCI. Repeated measure analyses of covariance revealed that greater age and MCI both significantly associated with slower gait speed, ps<.05. Follow-up analysis indicated that the MCI group had significantly slower dual-task gait speed but did not differ in simple-gait speed. Multivariate linear regression across groups found that executive attention performance accounted for 27.4% of the variance in dual-task gait speed beyond relevant demographic and health risk factors. The present study increases the external validity of dual-task gait assessment of MCI. Differences in dual-task gait speed appears to be largely attributable to executive attention processes. These findings have clinical implications as they demonstrate expected patterns of gait-brain behavior relationships in response to a cognitive dual task within a clinically representative population. Cognitive load dual-task gait assessment may provide a cost efficient and sensitive measure to detect older adults at high risk of a dementia disorder. (JINS, 2017, 23, 493-501).
Independent influence of gait speed and step length on stability and fall risk.
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.
Bibiloni, Maria Del Mar; Julibert, Alicia; Argelich, Emma; Aparicio-Ugarriza, Raquel; Palacios, Gonzalo; Pons, Antoni; Gonzalez-Gross, Marcela; Tur, Josep A
2017-07-06
Objectives: To assess prevailing food patterns, and its association with physical activity and fitness among Spanish older adults. Methods: Cross-sectional study in Spain, collecting data from a sample ( n = 380; 54% female) aged 55-80 years (men) and 60-80 years (women) with no previously documented cardiovascular disease. Body weight, body fat and waist circumference were assessed. Physical activity performed was measured using the Minnesota Leisure-time Physical Activity Questionnaire (LTPA). Physical fitness was assessed using a validated physical fitness test battery. Food consumption was assessed by a validated semi-quantitative food-frequency questionnaire. Factor analysis identified two major dietary food patterns: "Western" (WDP) and "Mediterranean" (MDP) dietary patterns. Results: Participants in MDP's fourth quartile were classified in the second (men) and third (men and women) tertile of LTPA. After adjusting for age, body fat, waist-to-height ratio, and METs, in both sexes, a negative significant association was found between 30-s Chair stand and 6-min walking test, a positive significant association was found between 30-m Gait speed and 8-foot Time Up-and-Go (except in men) tests with WDP. The 30-m Gait speed test was negatively associated with MDP in men. Conclusions: MDP is associated with more time spent on LTPA, and this association was independent of body composition and a fast gait speed in men. WDP is associated with slower gait speed and lower body strength, agility and aerobic endurance. MDP has protective effect on healthy physical fitness, and WDP may be a contributor to frailty.
Asymmetrical Pedaling Patterns in Parkinson's Disease Patients
Penko, Amanda L.; Hirsch, Joshua R.; Voelcker-Rehage, Claudia; Martin, Philip E.; Blackburn, Gordon; Alberts, Jay L.
2015-01-01
Background Approximately 1.5 million Americans are affected by Parkinson's disease [1] which includes the symptoms of postural instability and gait dysfunction. Currently, clinical evaluations of postural instability and gait dysfunction consist of a subjective rater assessment of gait patterns using items from the Unified Parkinson's Disease Rating Scale, and assessments can be insensitive to the effectiveness of medical interventions. Current research suggests the importance of cycling for Parkinson's disease patients, and while Parkinson's gait has been evaluated in previous studies, little is known about lower extremity control during cycling. The purpose of this study is to examine the lower extremity coordination patterns of Parkinson's patients during cycling. Methods Twenty five participants, ages 44-72, with a clinical diagnosis of idiopathic Parkinson's disease participated in an exercise test on a cycle ergometer that was equipped with pedal force measurements. Crank torque, crank angle and power produced by right and left leg were measured throughout the test to calculate Symmetry Index at three stages of exercise (20 Watt, 60 Watt, maximum performance). Findings Decreases in Symmetry Index were observed for average power output in Parkinson's patients as workload increased. Maximum power Symmetry Index showed a significant difference in symmetry between performance at both the 20 Watt and 60 Watt stage and the maximal resistance stage. Minimum power Symmetry Index did not show significant differences across the stages of the test. While lower extremity asymmetries were present in Parkinson's patients during pedaling, these asymmetries did not correlate to postural instability and gait dysfunction Unified Parkinson's Disease Rating Scale scores. Interpretation This pedaling analysis allows for a more sensitive measure of lower extremity function than the Unified Parkinson's Disease Rating Scale and may help to provide unique insight into current and future lower extremity function. PMID:25467810
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.
Papageorgiou, Eirini; Nieuwenhuys, Angela; Desloovere, Kaat
2017-01-01
Background This study aimed to improve the automatic probabilistic classification of joint motion gait patterns in children with cerebral palsy by using the expert knowledge available via a recently developed Delphi-consensus study. To this end, this study applied both Naïve Bayes and Logistic Regression classification with varying degrees of usage of the expert knowledge (expert-defined and discretized features). A database of 356 patients and 1719 gait trials was used to validate the classification performance of eleven joint motions. Hypotheses Two main hypotheses stated that: (1) Joint motion patterns in children with CP, obtained through a Delphi-consensus study, can be automatically classified following a probabilistic approach, with an accuracy similar to clinical expert classification, and (2) The inclusion of clinical expert knowledge in the selection of relevant gait features and the discretization of continuous features increases the performance of automatic probabilistic joint motion classification. Findings This study provided objective evidence supporting the first hypothesis. Automatic probabilistic gait classification using the expert knowledge available from the Delphi-consensus study resulted in accuracy (91%) similar to that obtained with two expert raters (90%), and higher accuracy than that obtained with non-expert raters (78%). Regarding the second hypothesis, this study demonstrated that the use of more advanced machine learning techniques such as automatic feature selection and discretization instead of expert-defined and discretized features can result in slightly higher joint motion classification performance. However, the increase in performance is limited and does not outweigh the additional computational cost and the higher risk of loss of clinical interpretability, which threatens the clinical acceptance and applicability. PMID:28570616
Why is walker-assisted gait metabolically expensive?
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.
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.
Quantifying gait deviations in individuals with rheumatoid arthritis using the Gait Deviation Index.
Esbjörnsson, A-C; Rozumalski, A; Iversen, M D; Schwartz, M H; Wretenberg, P; Broström, E W
2014-01-01
In this study we evaluated the usability of the Gait Deviation Index (GDI), an index that summarizes the amount of deviation in movement from a standard norm, in adults with rheumatoid arthritis (RA). The aims of the study were to evaluate the ability of the GDI to identify gait deviations, assess inter-trial repeatability, and examine the relationship between the GDI and walking speed, physical disability, and pain. Sixty-three adults with RA and 59 adults with typical gait patterns were included in this retrospective case-control study. Following a three-dimensional gait analysis (3DGA), representative gait cycles were selected and GDI scores calculated. To evaluate the effect of walking speed, GDI scores were calculated using both a free-speed and a speed-matched reference set. Physical disability was assessed using the Health Assessment Questionnaire (HAQ) and subjects rated their pain during walking. Adults with RA had significantly increased gait deviations compared to healthy individuals, as shown by lower GDI scores [87.9 (SD = 8.7) vs. 99.4 (SD = 8.3), p < 0.001]. This difference was also seen when adjusting for walking speed [91.7 (SD = 9.0) vs. 99.9 (SD = 8.6), p < 0.001]. It was estimated that a change of ≥ 5 GDI units was required to account for natural variation in gait. There was no evident relationship between GDI and low/high RA-related physical disability and pain. The GDI seems to useful for identifying and summarizing gait deviations in individuals with RA. Thus, we consider that the GDI provides an overall measure of gait deviation that may reflect lower extremity pathology and may help clinicians to understand the impact of RA on gait dynamics.
Reliability of videotaped observational gait analysis in patients with orthopedic impairments
Brunnekreef, Jaap J; van Uden, Caro JT; van Moorsel, Steven; Kooloos, Jan GM
2005-01-01
Background In clinical practice, visual gait observation is often used to determine gait disorders and to evaluate treatment. Several reliability studies on observational gait analysis have been described in the literature and generally showed moderate reliability. However, patients with orthopedic disorders have received little attention. The objective of this study is to determine the reliability levels of visual observation of gait in patients with orthopedic disorders. Methods The gait of thirty patients referred to a physical therapist for gait treatment was videotaped. Ten raters, 4 experienced, 4 inexperienced and 2 experts, individually evaluated these videotaped gait patterns of the patients twice, by using a structured gait analysis form. Reliability levels were established by calculating the Intraclass Correlation Coefficient (ICC), using a two-way random design and based on absolute agreement. Results The inter-rater reliability among experienced raters (ICC = 0.42; 95%CI: 0.38–0.46) was comparable to that of the inexperienced raters (ICC = 0.40; 95%CI: 0.36–0.44). The expert raters reached a higher inter-rater reliability level (ICC = 0.54; 95%CI: 0.48–0.60). The average intra-rater reliability of the experienced raters was 0.63 (ICCs ranging from 0.57 to 0.70). The inexperienced raters reached an average intra-rater reliability of 0.57 (ICCs ranging from 0.52 to 0.62). The two expert raters attained ICC values of 0.70 and 0.74 respectively. Conclusion Structured visual gait observation by use of a gait analysis form as described in this study was found to be moderately reliable. Clinical experience appears to increase the reliability of visual gait analysis. PMID:15774012
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.
Bez, Joelita Pessoa de Oliveira; Neri, Anita Liberalesso
2014-08-01
The article seeks to investigate patterns of performance and relationships between grip strength, gait speed and self-rated health, and investigate the relationships between them, considering the variables of gender, age and family income. This was conducted in a probabilistic sample of community-dwelling elderly aged 65 and over, members of a population study on frailty. A total of 689 elderly people without cognitive deficit suggestive of dementia underwent tests of gait speed and grip strength. Comparisons between groups were based on low, medium and high speed and strength. Self-related health was assessed using a 5-point scale. The males and the younger elderly individuals scored significantly higher on grip strength and gait speed than the female and oldest did; the richest scored higher than the poorest on grip strength and gait speed; females and men aged over 80 had weaker grip strength and lower gait speed; slow gait speed and low income arose as risk factors for a worse health evaluation. Lower muscular strength affects the self-rated assessment of health because it results in a reduction in functional capacity, especially in the presence of poverty and a lack of compensatory factors.
Bing, Zhenshan; Cheng, Long; Chen, Guang; Röhrbein, Florian; Huang, Kai; Knoll, Alois
2017-04-04
Snake-like robots with 3D locomotion ability have significant advantages of adaptive travelling in diverse complex terrain over traditional legged or wheeled mobile robots. Despite numerous developed gaits, these snake-like robots suffer from unsmooth gait transitions by changing the locomotion speed, direction, and body shape, which would potentially cause undesired movement and abnormal torque. Hence, there exists a knowledge gap for snake-like robots to achieve autonomous locomotion. To address this problem, this paper presents the smooth slithering gait transition control based on a lightweight central pattern generator (CPG) model for snake-like robots. First, based on the convergence behavior of the gradient system, a lightweight CPG model with fast computing time was designed and compared with other widely adopted CPG models. Then, by reshaping the body into a more stable geometry, the slithering gait was modified, and studied based on the proposed CPG model, including the gait transition of locomotion speed, moving direction, and body shape. In contrast to sinusoid-based method, extensive simulations and prototype experiments finally demonstrated that smooth slithering gait transition can be effectively achieved using the proposed CPG-based control method without generating undesired locomotion and abnormal torque.
Real-time feedback to improve gait in children with cerebral palsy.
van Gelder, Linda; Booth, Adam T C; van de Port, Ingrid; Buizer, Annemieke I; Harlaar, Jaap; van der Krogt, Marjolein M
2017-02-01
Real-time feedback may be useful for enhancing information gained from clinical gait analysis of children with cerebral palsy (CP). It may also be effective in functional gait training, however, it is not known if children with CP can adapt gait in response to real-time feedback of kinematic parameters. Sixteen children with cerebral palsy (age 6-16; GMFCS I-III), walking with a flexed-knee gait pattern, walked on an instrumented treadmill with virtual reality in three conditions: regular walking without feedback (NF), feedback on hip angle (FH) and feedback on knee angle (FK). Clinically relevant gait parameters were calculated and the gait profile score (GPS) was used as a measure of overall gait changes between conditions. All children, except one, were able to improve hip and/or knee extension during gait in response to feedback, with nine achieving a clinically relevant improvement. Peak hip extension improved significantly by 5.1±5.9° (NF: 8.9±12.8°, FH: 3.8±10.4°, p=0.01). Peak knee extension improved significantly by 7.7±7.1° (NF: 22.2±12.0°, FK: 14.5±12.7°, p<0.01). GPS did not change between conditions due to increased deviations in other gait parameters. Responders to feedback were shown to have worse initial gait as measured by GPS (p=0.005) and functional selectivity score (p=0.049). In conclusion, ambulatory children with CP show adaptability in gait and are able to respond to real-time feedback, resulting in significant and clinically relevant improvements in peak hip and knee extension. These findings show the potential of real-time feedback as a tool for functional gait training and advanced gait analysis in CP. Copyright © 2016 Elsevier B.V. All rights reserved.
Goudriaan, Marije; Van den Hauwe, Marleen; Simon-Martinez, Cristina; Huenaerts, Catherine; Molenaers, Guy; Goemans, Nathalie; Desloovere, Kaat
2018-04-30
Prolonged ambulation is considered important in children with Duchenne muscular dystrophy (DMD). However, previous studies analyzing DMD gait were sensitive to false positive outcomes, caused by uncorrected multiple comparisons, regional focus bias, and inter-component covariance bias. Also, while muscle weakness is often suggested to be the main cause for the altered gait pattern in DMD, this was never verified. Our research question was twofold: 1) are we able to confirm the sagittal kinematic and kinetic gait alterations described in a previous review with statistical non-parametric mapping (SnPM)? And 2) are these gait deviations related to lower limb weakness? We compared gait kinematics and kinetics of 15 children with DMD and 15 typical developing (TD) children (5-17 years), with a two sample Hotelling's T 2 test and post-hoc two-tailed, two-sample t-test. We used canonical correlation analyses to study the relationship between weakness and altered gait parameters. For all analyses, α-level was corrected for multiple comparisons, resulting in α = 0.005. We only found one of the previously reported kinematic deviations: the children with DMD had an increased knee flexion angle during swing (p = 0.0006). Observed gait deviations that were not reported in the review were an increased hip flexion angle during stance (p = 0.0009) and swing (p = 0.0001), altered combined knee and ankle torques (p = 0.0002), and decreased power absorption during stance (p = 0.0001). No relationships between weakness and these gait deviations were found. We were not able to replicate the gait deviations in DMD previously reported in literature, thus DMD gait remains undefined. Further, weakness does not seem to be linearly related to altered gait features. The progressive nature of the disease requires larger study populations and longitudinal analyses to gain more insight into DMD gait and its underlying causes. Copyright © 2018 Elsevier B.V. All rights reserved.
Secure and Privacy Enhanced Gait Authentication on Smart Phone
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. PMID:24955403
Ambiguity domain-based identification of altered gait pattern in ALS disorder
NASA Astrophysics Data System (ADS)
Sugavaneswaran, L.; Umapathy, K.; Krishnan, S.
2012-08-01
The onset of a neurological disorder, such as amyotrophic lateral sclerosis (ALS), is so subtle that the symptoms are often overlooked, thereby ruling out the option of early detection of the abnormality. In the case of ALS, over 75% of the affected individuals often experience awkwardness when using their limbs, which alters their gait, i.e. stride and swing intervals. The aim of this work is to suitably represent the non-stationary characteristics of gait (fluctuations in stride and swing intervals) in order to facilitate discrimination between normal and ALS subjects. We define a simple-yet-representative feature vector space by exploiting the ambiguity domain (AD) to achieve efficient classification between healthy and pathological gait stride interval. The stride-to-stride fluctuations and the swing intervals of 16 healthy control and 13 ALS-affected subjects were analyzed. Three features that are representative of the gait signal characteristics were extracted from the AD-space and are fed to linear discriminant analysis and neural network classifiers, respectively. Overall, maximum accuracies of 89.2% (LDA) and 100% (NN) were obtained in classifying the ALS gait.
Video gait analysis for ambulatory children with cerebral palsy: Why, when, where and how!
Harvey, Adrienne; Gorter, Jan Willem
2011-03-01
This paper outlines the application of video gait analysis (VGA) for children with cerebral palsy (CP) when full instrumented three dimensional gait analysis (3DGA) is either not indicated or not available. Gait analysis is an important part of the assessment of ambulant children with CP for diagnosing gait deviations and for evaluating change. Many regard 3DGA as the most informative method of assessing gait, however, it is not always accessible, practical, or feasible and the detail obtained is not always indicated. VGA in conjunction with other carefully selected outcome measures can provide a comprehensive gait assessment in situations where 3DGA is not available or not indicated. Indications for VGA use include: documenting change in gait pattern over time, frequent monitoring in the rehabilitation phase following treatments and interventions (including surgery, spasticity management, serial casting and intensive therapy), monitoring orthotic changes, and for very young children and those with behavioural/cognitive issues that preclude them from cooperating with a 3DGA. Simple and inexpensive VGA systems can be set up in most settings. In an effort to make the process more objective and reliable a number of observational gait scales have been developed. Of these the Edinburgh Gait Score (EGS) has the strongest psychometric properties and is the most comprehensive by including both the coronal and the sagittal planes. While 3DGA remains an important part of complex clinical decision-making, there is also an increasingly important role for VGA. Guidelines need to be developed for its use within the field of gait analysis. Crown Copyright © 2010. Published by Elsevier B.V. All rights reserved.
Labriffe, Matthieu; Annweiler, Cédric; Amirova, Liubov E; Gauquelin-Koch, Guillemette; Ter Minassian, Aram; Leiber, Louis-Marie; Beauchet, Olivier; Custaud, Marc-Antoine; Dinomais, Mickaël
2017-01-01
Human locomotion is a complex sensorimotor behavior whose central control remains difficult to explore using neuroimaging method due to technical constraints, notably the impossibility to walk with a scanner on the head and/or to walk for real inside current scanners. The aim of this functional Magnetic Resonance Imaging (fMRI) study was to analyze interactions between two paradigms to investigate the brain gait control network: (1) mental imagery of gait, and (2) passive mechanical stimulation of the plantar surface of the foot with the Korvit boots. The Korvit stimulator was used through two different modes, namely an organized ("gait like") sequence and a destructured (chaotic) pattern. Eighteen right-handed young healthy volunteers were recruited (mean age, 27 ± 4.7 years). Mental imagery activated a broad neuronal network including the supplementary motor area-proper (SMA-proper), pre-SMA, the dorsal premotor cortex, ventrolateral prefrontal cortex, anterior insula, and precuneus/superior parietal areas. The mechanical plantar stimulation activated the primary sensorimotor cortex and secondary somatosensory cortex bilaterally. The paradigms generated statistically common areas of activity, notably bilateral SMA-proper and right pre-SMA, highlighting the potential key role of SMA in gait control. There was no difference between the organized and chaotic Korvit sequences, highlighting the difficulty of developing a walking-specific plantar stimulation paradigm. In conclusion, this combined-fMRI paradigm combining mental imagery and gait-like plantar stimulation provides complementary information regarding gait-related brain activity and appears useful for the assessment of high-level gait control.
Health Monitors for Chronic Disease by Gait Analysis with Mobile Phones
Juen, Joshua; Cheng, Qian; Prieto-Centurion, Valentin; Krishnan, Jerry A.
2014-01-01
Abstract We have developed GaitTrack, a phone application to detect health status while the smartphone is carried normally. GaitTrack software monitors walking patterns, using only accelerometers embedded in phones to record spatiotemporal motion, without the need for sensors external to the phone. Our software transforms smartphones into health monitors, using eight parameters of phone motion transformed into body motion by the gait model. GaitTrack is designed to detect health status while the smartphone is carried during normal activities, namely, free-living walking. The current method for assessing free-living walking is medical accelerometers, so we present evidence that mobile phones running our software are more accurate. We then show our gait model is more accurate than medical pedometers for counting steps of patients with chronic disease. Our gait model was evaluated in a pilot study involving 30 patients with chronic lung disease. The six-minute walk test (6MWT) is a major assessment for chronic heart and lung disease, including congestive heart failure and especially chronic obstructive pulmonary disease (COPD), affecting millions of persons. The 6MWT consists of walking back and forth along a measured distance for 6 minutes. The gait model using linear regression performed with 94.13% accuracy in measuring walk distance, compared with the established standard of direct observation. We also evaluated a different statistical model using the same gait parameters to predict health status through lung function. This gait model has high accuracy when applied to demographic cohorts, for example, 89.22% accuracy testing the cohort of 12 female patients with ages 50–64 years. PMID:24694291
NASA Astrophysics Data System (ADS)
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 could need others specific external cues. In conclusion the current protocol (and their selected parameters, kind of sound time for training, step of variation, range of variation) provide a suitable gait facilitation method specially for patients with the highest gait disturbance (stage 2 and 3). The method should be adjusted for initial stages and evaluated in a rehabilitation program.
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 speed, fractal dynamics increased closer to 1/f when participants were exposed to asymmetric walking. These findings suggest there may not be a relationship between unperturbed preferred or slow speed walking fractal dynamics and gait adaptability. However, the emergent relationship between asymmetric walking fractal dynamics and limb phase adaptation may represent a functional reorganization of the locomotor system (i.e., improved interactivity between degrees of freedom within the system) to be better suited to attenuate externally generated perturbations at various spatiotemporal scales. Copyright © 2018 Elsevier B.V. All rights reserved.
The feasibility of singing to improve gait in Parkinson disease
Harrison, Elinor C.; McNeely, Marie E.; Earhart, Gammon M.
2017-01-01
Brain regions important for controlling movement are also responsible for rhythmic processing. In Parkinson disease (PD), defective internal timing within the brain has been linked to impaired beat discrimination, and may contribute to a loss of ability to maintain a steady gait rhythm. Less rhythmic gait is inherently less efficient, and this may lead to gait impairment including reduced speed, cadence, and stride length, as well as increased variability. While external rhythmic auditory stimulation (e.g. a metronome beat) is well-established as an effective tool to stabilize gait in PD, little is known about whether self-generated cues such as singing have the same beneficial effect on gait in PD. Thus, we compared gait patterns of 23 people with mild to moderate PD under five cued conditions: uncued, music only, singing only, singing with music, and a verbal dual-task condition. In our single session study, singing while walking did not significantly alter velocity, cadence, or stride length, indicating that it was not excessively demanding for people with PD. In addition, walking was less variable when singing than during other cued conditions. This was further supported by the comparison between singing trials and a verbal dual-task condition. In contrast to singing, the verbal dual-task negatively affected gait performance. These findings suggest that singing holds promise as an effective cueing technique that may be as good as or better than traditional cueing techniques for improving gait among people with PD. PMID:28226309
The feasibility of singing to improve gait in Parkinson disease.
Harrison, Elinor C; McNeely, Marie E; Earhart, Gammon M
2017-03-01
Brain regions important for controlling movement are also responsible for rhythmic processing. In Parkinson disease (PD), defective internal timing within the brain has been linked to impaired beat discrimination, and may contribute to a loss of ability to maintain a steady gait rhythm. Less rhythmic gait is inherently less efficient, and this may lead to gait impairment including reduced speed, cadence, and stride length, as well as increased variability. While external rhythmic auditory stimulation (e.g. a metronome beat) is well-established as an effective tool to stabilize gait in PD, little is known about whether self-generated cues such as singing have the same beneficial effect on gait in PD. Thus, we compared gait patterns of 23 people with mild to moderate PD under five cued conditions: uncued, music only, singing only, singing with music, and a verbal dual-task condition. In our single-session study, singing while walking did not significantly alter velocity, cadence, or stride length, indicating that it was not excessively demanding for people with PD. In addition, walking was less variable when singing than during other cued conditions. This was further supported by the comparison between singing trials and a verbal dual-task condition. In contrast to singing, the verbal dual-task negatively affected gait performance. These findings suggest that singing holds promise as an effective cueing technique that may be as good as or better than traditional cueing techniques for improving gait among people with PD. Copyright © 2017 Elsevier B.V. All rights reserved.
Crouch severity is a poor predictor of elevated oxygen consumption in cerebral palsy.
Steele, Katherine M; Shuman, Benjamin R; Schwartz, Michael H
2017-07-26
Children with cerebral palsy (CP) expend more energy to walk compared to typically-developing peers. One of the most prevalent gait patterns among children with CP, crouch gait, is often singled out as especially exhausting. The dynamics of crouch gait increase external flexion moments and the demand on extensor muscles. This elevated demand is thought to dramatically increase energy expenditure. However, the impact of crouch severity on energy expenditure has not been investigated among children with CP. We evaluated oxygen consumption and gait kinematics for 573 children with bilateral CP. The average net nondimensional oxygen consumption during gait of the children with CP (0.18±0.06) was 2.9 times that of speed-matched typically-developing peers. Crouch severity was only modestly related to oxygen consumption, with measures of knee flexion angle during gait explaining only 5-20% of the variability in oxygen consumption. While knee moment and muscle activity were moderately to strongly correlated with crouch severity (r 2 =0.13-0.73), these variables were only weakly correlated with oxygen consumption (r 2 =0.02-0.04). Thus, although the dynamics of crouch gait increased muscle demand, these effects did not directly result in elevated energy expenditure. In clinical gait analysis, assumptions about an individual's energy expenditure should not be based upon kinematics or kinetics alone. Identifying patient-specific factors that contribute to increased energy expenditure may provide new pathways to improve gait for children with CP. Copyright © 2017 Elsevier Ltd. All rights reserved.
Invariant ankle moment patterns when walking with and without a robotic ankle exoskeleton.
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, p<0.05). Not all of the subjects reached a steady-state gait pattern within the two sessions, in contrast to a previous study using a weaker robotic 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.
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. PMID:27516737
Sylos-Labini, Francesca; d'Avella, Andrea; Lacquaniti, Francesco; Ivanenko, Yury
2018-01-01
Handholding can naturally occur between two walkers. When people walk side-by-side, either with or without hand contact, they often synchronize their steps. However, despite the importance of haptic interaction in general and the natural use of hand contact between humans during walking, few studies have investigated forces arising from physical interactions. Eight pairs of adult subjects participated in this study. They walked on side-by-side treadmills at 4 km/h independently and with hand contact. Only hand contact-related sensory information was available for unintentional synchronization, while visual and auditory communication was obstructed. Subjects walked at their natural cadences or following a metronome. Limb kinematics, hand contact 3D interaction forces and EMG activity of 12 upper limb muscles were recorded. Overall, unintentional step frequency locking was observed during about 40% of time in 88% of pairs walking with hand contact. On average, the amplitude of contact arm oscillations decreased while the contralateral (free) arm oscillated in the same way as during normal walking. Interestingly, EMG activity of the shoulder muscles of the contact arm did not decrease, and their synergistic pattern remained similar. The amplitude of interaction forces and of trunk oscillations was similar for synchronized and non-synchronized steps, though the synchronized steps were characterized by significantly more regular orientations of interaction forces. Our results further support the notion that gait synchronization during natural walking is common, and that it may occur through interaction forces. Conservation of the proximal muscle activity of the contact (not oscillating) arm is consistent with neural coupling between cervical and lumbosacral pattern generation circuitries ("quadrupedal" arm-leg coordination) during human gait. Overall, the findings suggest that individuals might integrate force interaction cues to communicate and coordinate steps during walking.
Sylos-Labini, Francesca; d'Avella, Andrea; Lacquaniti, Francesco; Ivanenko, Yury
2018-01-01
Handholding can naturally occur between two walkers. When people walk side-by-side, either with or without hand contact, they often synchronize their steps. However, despite the importance of haptic interaction in general and the natural use of hand contact between humans during walking, few studies have investigated forces arising from physical interactions. Eight pairs of adult subjects participated in this study. They walked on side-by-side treadmills at 4 km/h independently and with hand contact. Only hand contact-related sensory information was available for unintentional synchronization, while visual and auditory communication was obstructed. Subjects walked at their natural cadences or following a metronome. Limb kinematics, hand contact 3D interaction forces and EMG activity of 12 upper limb muscles were recorded. Overall, unintentional step frequency locking was observed during about 40% of time in 88% of pairs walking with hand contact. On average, the amplitude of contact arm oscillations decreased while the contralateral (free) arm oscillated in the same way as during normal walking. Interestingly, EMG activity of the shoulder muscles of the contact arm did not decrease, and their synergistic pattern remained similar. The amplitude of interaction forces and of trunk oscillations was similar for synchronized and non-synchronized steps, though the synchronized steps were characterized by significantly more regular orientations of interaction forces. Our results further support the notion that gait synchronization during natural walking is common, and that it may occur through interaction forces. Conservation of the proximal muscle activity of the contact (not oscillating) arm is consistent with neural coupling between cervical and lumbosacral pattern generation circuitries (“quadrupedal” arm-leg coordination) during human gait. Overall, the findings suggest that individuals might integrate force interaction cues to communicate and coordinate steps during walking. PMID:29563883
Miyake, Tamon; Kobayashi, Yo; Fujie, Masakatsu G; Sugano, Shigeki
2017-07-01
Gait training robots are useful for changing gait patterns and decreasing risk of trip. Previous research has reported that decreasing duration of the assistance or guidance of the robot is beneficial for efficient gait training. Although robotic intermittent control method for assisting joint motion has been established, the effect of the robot intervention timing on change of toe clearance is unclear. In this paper, we tested different timings of applying torque to the knee, employing the intermittent control of a gait training robot to increase toe clearance throughout the swing phase. We focused on knee flexion motion and designed a gait training robot that can apply flexion torque to the knee with a wire-driven system. We used a method of timing detecting for the robot conducting torque control based on information from the hip, knee, and ankle angles to establish a non-time dependent parameter that can be used to adapt to gait change, such as gait speed. We carried out an experiment in which the conditions were four time points: starting the swing phase, lifting the foot, maintaining knee flexion, and finishing knee flexion. The results show that applying flexion torque to the knee at the time point when people start lifting their toe is effective for increasing toe clearance in the whole swing phase.
Towards a Passive Low-Cost In-Home Gait Assessment System for Older Adults
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
Upper limb movement analysis during gait in multiple sclerosis patients.
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.
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 (p<0.05) in the peak values for hip flexion angle, dorsiflexor moment, ankle power generation, propulsion force, braking impulse, and propulsive impulse were found in patients with PAD compared to healthy controls. No significant differences were observed between patients with COPD and controls. The results of this study demonstrate that while gait 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.
Zhang, Li; Li, Tian-Nv; Yuan, Yong-Sheng; Jiang, Si-Ming; Tong, Qing; Wang, Min; Wang, Jian-Wei; Chen, Hua-Jun; Ding, Jian; Xu, Qin-Rong; Zhang, Ke-Zhong
2016-05-01
The aim of this study is to further uncover the neural basis of postural instability gait disorder (PIGD) subtype of Parkinson's disease. With F-18 fluorodeoxyglucose PET (FDG-PET), brain glucose metabolism of patients with PIGD (n = 15) was compared with healthy controls (n = 17) and tremor-dominant (TD) patients (n = 15), and the correlation between metabolism and PIGD symptoms was also assessed. Within PIGD symptom-correlated hypometabolic areas, the relationship of functional connectivity (FC) with motor and cognitive symptoms was examined by using functional MRI. Compared with controls, patients with PIGD displayed a distributed pattern of brain hypometabolism including striatal, frontal, and parietal areas. Relative to the pattern of TD patients, the pattern of patients with PIGD had additional metabolic decreases in caudate and inferior parietal lobule (IPL, Brodmann area [BA] 40). In PIGD group, the metabolic reductions in IPL (BA 40), middle frontal gyrus (MFG, BA 9) and fusiform gyrus (FG, BA 20) were associated with severe PIGD symptoms. Regions showing such correlation were chosen for further seed-based FC analysis. Decreased FC within the prefrontal-parietal network (between the MFG and IPL) was associated with severe PIGD symptoms. The involvement of the caudate, FG, and prefrontal-parietal network may be associated with the prominent gait impairments of PIGD subtype. Our findings expand the pathophysiological knowledge of PIGD subtype and provide valuable information for potential neuromodulation therapies alleviating gait disorders. © 2016 John Wiley & Sons Ltd.
Inducing self-selected human engagement in robotic locomotion training.
Collins, Steven H; Jackson, Rachel W
2013-06-01
Stroke leads to severe mobility impairments for millions of individuals each year. Functional outcomes can be improved through manual treadmill therapy, but high costs limit patient exposure and, thereby, outcomes. Robotic gait training could increase the viable duration and frequency of training sessions, but robotic approaches employed thus far have been less effective than manual therapy. These shortcomings may relate to subconscious energy-minimizing drives, which might cause patients to engage less actively in therapy when provided with corrective robotic assistance. We have devised a new method for gait rehabilitation that harnesses, rather than fights, least-effort tendencies. Therapeutic goals, such as increased use of the paretic limb, are made easier than the patient's nominal gait through selective assistance from a robotic platform. We performed a pilot test on a healthy subject (N = 1) in which altered self-selected stride length was induced using a tethered robotic ankle-foot orthosis. The subject first walked on a treadmill while wearing the orthosis with and without assistance at unaltered and voluntarily altered stride length. Voluntarily increasing stride length by 5% increased metabolic energy cost by 4%. Robotic assistance decreased energy cost at both unaltered and voluntarily increased stride lengths, by 6% and 8% respectively. We then performed a test in which the robotic system continually monitored stride length and provided more assistance if the subject's stride length approached a target increase. This adaptive assistance protocol caused the subject to slowly adjust their gait patterns towards the target, leading to a 4% increase in stride length. Metabolic energy consumption was simultaneously reduced by 5%. These results suggest that selective-assistance protocols based on targets relevant to rehabilitation might lead patients to self-select desirable gait patterns during robotic gait training sessions, possibly facilitating better adherence and outcomes.
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 (P<0.05). Except for the knee flexion/extension angle, two different groups (G(1) and G(2)) were extracted from the angle and moment data. When pre- and post-treatment analyses were performed considering the groups, participants exhibiting a G(2) knee moment pattern demonstrated a greater first peak flexion moment, lower adduction moment impulse and smaller rotation angle range post-treatment (P<0.05). When pre- and post-treatment comparisons were performed without grouping, the data showed no treatment effect. The results of the present study suggest that the effect of physiotherapy 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.
2010-01-01
Background Stair climbing up and down is an essential part of everyday's mobility. To enable wheelchair-dependent patients the repetitive practice of this task, a novel gait robot, G-EO-Systems (EO, Lat: I walk), based on the end-effector principle, has been designed. The trajectories of the foot plates are freely programmable enabling not only the practice of simulated floor walking but also stair climbing up and down. The article intended to compare lower limb muscle activation patterns of hemiparetic subjects during real floor walking and stairs climbing up, and during the corresponding simulated conditions on the machine, and secondly to demonstrate gait improvement on single case after training on the machine. Methods The muscle activation pattern of seven lower limb muscles of six hemiparetic patients during free and simulated walking on the floor and stair climbing was measured via dynamic electromyography. A non-ambulatory, sub-acute stroke patient additionally trained on the G-EO-Systems every workday for five weeks. Results The muscle activation patterns were comparable during the real and simulated conditions, both on the floor and during stair climbing up. Minor differences, concerning the real and simulated floor walking conditions, were a delayed (prolonged) onset (duration) of the thigh muscle activation on the machine across all subjects. Concerning stair climbing conditions, the shank muscle activation was more phasic and timely correct in selected patients on the device. The severely affected subject regained walking and stair climbing ability. Conclusions The G-EO-Systems is an interesting new option in gait rehabilitation after stroke. The lower limb muscle activation patterns were comparable, a training thus feasible, and the positive case report warrants further clinical studies. PMID:20584307
Hesse, Stefan; Waldner, Andreas; Tomelleri, Christopher
2010-06-28
Stair climbing up and down is an essential part of everyday's mobility. To enable wheelchair-dependent patients the repetitive practice of this task, a novel gait robot, G-EO-Systems (EO, Lat: I walk), based on the end-effector principle, has been designed. The trajectories of the foot plates are freely programmable enabling not only the practice of simulated floor walking but also stair climbing up and down. The article intended to compare lower limb muscle activation patterns of hemiparetic subjects during real floor walking and stairs climbing up, and during the corresponding simulated conditions on the machine, and secondly to demonstrate gait improvement on single case after training on the machine. The muscle activation pattern of seven lower limb muscles of six hemiparetic patients during free and simulated walking on the floor and stair climbing was measured via dynamic electromyography. A non-ambulatory, sub-acute stroke patient additionally trained on the G-EO-Systems every workday for five weeks. The muscle activation patterns were comparable during the real and simulated conditions, both on the floor and during stair climbing up. Minor differences, concerning the real and simulated floor walking conditions, were a delayed (prolonged) onset (duration) of the thigh muscle activation on the machine across all subjects. Concerning stair climbing conditions, the shank muscle activation was more phasic and timely correct in selected patients on the device. The severely affected subject regained walking and stair climbing ability. The G-EO-Systems is an interesting new option in gait rehabilitation after stroke. The lower limb muscle activation patterns were comparable, a training thus feasible, and the positive case report warrants further clinical studies.
Bukowska, Anna A; Krężałek, Piotr; Mirek, Elżbieta; Bujas, Przemysław; Marchewka, Anna
2015-01-01
Idiopathic Parkinson's Disease (PD) is a progressive condition with gait disturbance and balance disorder as the main symptoms. Previous research studies focused on the application of Rhythmic Auditory Stimulation (RAS) in PD gait rehabilitation. The key hypothesis of this pilot study, however, assumes the major role of the combination of all three Neurologic Music Therapy (NMT) sensorimotor techniques in improving spatio-temporal gait parameters, and postural stability in the course of PD. The 55 PD-diagnosed subjects invited to the study were divided into two groups: 30 in the experimental and 25 in the control group. Inclusion criteria included Hoehn and Yahr stages 2 or 3, the ability to walk independently without any aid and stable pharmacological treatment for the duration of the experiment. In order to evaluate the efficacy of the chosen therapy procedure the following measures were applied: Optoelectrical 3D Movement Analysis, System BTS Smart for gait, and Computerized Dynamic Posturography CQ Stab for stability and balance. All measures were conducted both before and after the therapy cycle. The subjects from the experimental group attended music therapy sessions four times a week for 4 weeks. Therapeutic Instrumental Music Performance (TIMP), Pattern Sensory Enhancement (PSE) and RAS were used in every 45-min session for practicing daily life activities, balance, pre-gait, and gait pattern. Percussion instruments, the metronome and rhythmic music were the basis for each session. The subjects from the control group were asked to stay active and perform daily life activities between the measures. The research showed that the combination of the three NMT sensorimotor techniques can be used to improve gait and other rhythmical activities in PD rehabilitation. The results demonstrated significant improvement in the majority of the spatiotemporal gait parameters in the experimental group in comparison to the control group. In the stability tests with eyes closed, substantial differences were revealed, indicating improvement of proprioception (the sense of body position and movement). These findings suggest a new compensatory strategy for movement and postural control through the use of the auditory system.
Bukowska, Anna A.; Krężałek, Piotr; Mirek, Elżbieta; Bujas, Przemysław; Marchewka, Anna
2016-01-01
Idiopathic Parkinson’s Disease (PD) is a progressive condition with gait disturbance and balance disorder as the main symptoms. Previous research studies focused on the application of Rhythmic Auditory Stimulation (RAS) in PD gait rehabilitation. The key hypothesis of this pilot study, however, assumes the major role of the combination of all three Neurologic Music Therapy (NMT) sensorimotor techniques in improving spatio-temporal gait parameters, and postural stability in the course of PD. The 55 PD-diagnosed subjects invited to the study were divided into two groups: 30 in the experimental and 25 in the control group. Inclusion criteria included Hoehn and Yahr stages 2 or 3, the ability to walk independently without any aid and stable pharmacological treatment for the duration of the experiment. In order to evaluate the efficacy of the chosen therapy procedure the following measures were applied: Optoelectrical 3D Movement Analysis, System BTS Smart for gait, and Computerized Dynamic Posturography CQ Stab for stability and balance. All measures were conducted both before and after the therapy cycle. The subjects from the experimental group attended music therapy sessions four times a week for 4 weeks. Therapeutic Instrumental Music Performance (TIMP), Pattern Sensory Enhancement (PSE) and RAS were used in every 45-min session for practicing daily life activities, balance, pre-gait, and gait pattern. Percussion instruments, the metronome and rhythmic music were the basis for each session. The subjects from the control group were asked to stay active and perform daily life activities between the measures. The research showed that the combination of the three NMT sensorimotor techniques can be used to improve gait and other rhythmical activities in PD rehabilitation. The results demonstrated significant improvement in the majority of the spatiotemporal gait parameters in the experimental group in comparison to the control group. In the stability tests with eyes closed, substantial differences were revealed, indicating improvement of proprioception (the sense of body position and movement). These findings suggest a new compensatory strategy for movement and postural control through the use of the auditory system. PMID:26858628
Interrater reliability of videotaped observational gait-analysis assessments.
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.
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.
Markerless identification of key events in gait cycle using image flow.
Vishnoi, Nalini; Duric, Zoran; Gerber, Naomi Lynn
2012-01-01
Gait analysis has been an interesting area of research for several decades. In this paper, we propose image-flow-based methods to compute the motion and velocities of different body segments automatically, using a single inexpensive video camera. We then identify and extract different events of the gait cycle (double-support, mid-swing, toe-off and heel-strike) from video images. Experiments were conducted in which four walking subjects were captured from the sagittal plane. Automatic segmentation was performed to isolate the moving body from the background. The head excursion and the shank motion were then computed to identify the key frames corresponding to different events in the gait cycle. Our approach does not require calibrated cameras or special markers to capture movement. We have also compared our method with the Optotrak 3D motion capture system and found our results in good agreement with the Optotrak results. The development of our method has potential use in the markerless and unencumbered video capture of human locomotion. Monitoring gait in homes and communities provides a useful application for the aged and the disabled. Our method could potentially be used as an assessment tool to determine gait symmetry or to establish the normal gait pattern of an individual.
Comparing electro- and mechano-myographic muscle activation patterns in self-paced pediatric gait.
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.
Morphology and the gradient of a symmetric potential predict gait transitions of dogs.
Wilshin, Simon; Haynes, G Clark; Porteous, Jack; Koditschek, Daniel; Revzen, Shai; Spence, Andrew J
2017-08-01
Gaits and gait transitions play a central role in the movement of animals. Symmetry is thought to govern the structure of the nervous system, and constrain the limb motions of quadrupeds. We quantify the symmetry of dog gaits with respect to combinations of bilateral, fore-aft, and spatio-temporal symmetry groups. We tested the ability of symmetries to model motion capture data of dogs walking, trotting and transitioning between those gaits. Fully symmetric models performed comparably to asymmetric with only a [Formula: see text] increase in the residual sum of squares and only one-quarter of the parameters. This required adding a spatio-temporal shift representing a lag between fore and hind limbs. Without this shift, the symmetric model residual sum of squares was [Formula: see text] larger. This shift is related to (linear regression, [Formula: see text], [Formula: see text]) dog morphology. That this symmetry is respected throughout the gaits and transitions indicates that it generalizes outside a single gait. We propose that relative phasing of limb motions can be described by an interaction potential with a symmetric structure. This approach can be extended to the study of interaction of neurodynamic and kinematic variables, providing a system-level model that couples neuronal central pattern generator networks and mechanical models.
Afzal, Muhammad Raheel; Pyo, Sanghun; Oh, Min-Kyun; Park, Young Sook; Yoon, Jungwon
2018-04-16
Integration of kinesthetic and tactile cues for application to post-stroke gait rehabilitation is a novel concept which needs to be explored. The combined provision of haptic cues may result in collective improvement of gait parameters such as symmetry, balance and muscle activation patterns. Our proposed integrated cue system can offer a cost-effective and voluntary gait training experience for rehabilitation of subjects with unilateral hemiparetic stroke. Ten post-stroke ambulatory subjects participated in a 10 m walking trial while utilizing the haptic cues (either alone or integrated application), at their preferred and increased gait speeds. In the system a haptic cane device (HCD) provided kinesthetic perception and a vibrotactile feedback device (VFD) provided tactile cue on the paretic leg for gait modification. Balance, gait symmetry and muscle activity were analyzed to identify the benefits of utilizing the proposed system. When using kinesthetic cues, either alone or integrated with a tactile cue, an increase in the percentage of non-paretic peak activity in the paretic muscles was observed at the preferred gait speed (vastus medialis obliquus: p < 0.001, partial eta squared (η 2 ) = 0.954; semitendinosus p < 0.001, partial η 2 = 0.793) and increased gait speeds (vastus medialis obliquus: p < 0.001, partial η 2 = 0.881; semitendinosus p = 0.028, partial η 2 = 0.399). While using HCD and VFD (individual and integrated applications), subjects could walk at their preferred and increased gait speeds without disrupting trunk balance in the mediolateral direction. The temporal stance symmetry ratio was improved when using tactile cues, either alone or integrated with a kinesthetic cue, at their preferred gait speed (p < 0.001, partial η 2 = 0.702). When combining haptic cues, the subjects walked at their preferred gait speed with increased temporal stance symmetry and paretic muscle activity affecting their balance. Similar improvements were observed at higher gait speeds. The efficacy of the proposed system is influenced by gait speed. Improvements were observed at a 20% increased gait speed, whereas, a plateau effect was observed at a 40% increased gait speed. These results imply that integration of haptic cues may benefit post-stroke gait rehabilitation by inducing simultaneous improvements in gait symmetry and muscle activity.
The influence of the Re-Link Trainer on gait symmetry in healthy adults.
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.
Planning strategies for the Ambler walking robot
NASA Technical Reports Server (NTRS)
Wettergreen, David; Thomas, Hans; Thorpe, Chuck
1990-01-01
A hierarchy of planning strategies is proposed and explained for a walking robot called the Ambler. The hierarchy decomposes planning into levels of trajectory, gait, and footfall. An abstraction of feasible traversability allows the Ambler's trajectory planner to identify acceptable trajectories by finding paths that guarantee footfalls without specifying exactly which footfalls. Leg and body moves that achieve this trajectory can be generated by the Ambler's gait planner, which incorporates pattern constraints and measures of utility to search for the best next move. By combining constraints from the quality and details of the terrain, the Ambler's footfall planner can select footfalls that insure stability and remain within the tolerances of the gait.
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.
2014-01-01
Background Infants born preterm commonly suffer from a combination of hypoxia-ischemia (HI) and infectious perinatal inflammatory insults that lead to cerebral palsy, cognitive delay, behavioral issues and epilepsy. Using a novel rat model of combined late gestation HI and lipopolysaccharide (LPS)-induced inflammation, we tested our hypothesis that inflammation from HI and LPS differentially affects gliosis, white matter development and motor impairment during the first postnatal month. Methods Pregnant rats underwent laparotomy on embryonic day 18 and transient systemic HI (TSHI) and/or intra-amniotic LPS injection. Shams received laparotomy and anesthesia only. Pups were born at term. Immunohistochemistry with stereological estimates was performed to assess regional glial loads, and western blots were performed for protein expression. Erythropoietin ligand and receptor levels were quantified using quantitative PCR. Digigait analysis detected gait deficits. Statistical analysis was performed with one-way analysis of variance and post-hoc Bonferonni correction. Results Microglial and astroglial immunolabeling are elevated in TSHI + LPS fimbria at postnatal day 2 compared to sham (both P < 0.03). At postnatal day 15, myelin basic protein expression is reduced by 31% in TSHI + LPS pups compared to shams (P < 0.05). By postnatal day 28, white matter injury shifts from the acute injury pattern to a chronic injury pattern in TSHI pups only. Both myelin basic protein expression (P < 0.01) and the phosphoneurofilament/neurofilament ratio, a marker of axonal dysfunction, are reduced in postnatal day 28 TSHI pups (P < 0.001). Erythropoietin ligand to receptor ratios differ between brains exposed to TSHI and LPS. Gait analyses reveal that all groups (TSHI, LPS and TSHI + LPS) are ataxic with deficits in stride, paw placement, gait consistency and coordination (all P < 0.001). Conclusions Prenatal TSHI and TSHI + LPS lead to different patterns of injury with respect to myelination, axon integrity and gait deficits. Dual injury leads to acute alterations in glial response and cellular inflammation, while TSHI alone causes more prominent chronic white matter and axonal injury. Both injuries cause significant gait deficits. Further study will contribute to stratification of injury mechanisms in preterm infants, and guide the use of promising therapeutic interventions. PMID:25082427
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.
Dystonic pattern in a fibromyalgia patient: relevance of a biopsychosocial rehabilitation approach.
Prist, V; De Wilde, V-A; Masquelier, E
2012-04-01
We present the complex case of a 49-year-old woman who worked as a cook in a school cafeteria and has been suffering from widespread pain since 2002. This patient showed a very particular gait pattern with hips adduction, flexed hips and knees and bilateral equinus foot deformity. Clinical examinations conducted by various clinicians, such as physical medicine and rehabilitation (PM&R) physicians and neurologists, yielded very different diagnostic hypotheses, each being nevertheless quite "logical": fibromyalgia syndrome with dystonia, CNS injury, Little's disease, intramedullary spinal cord tumor or multiple sclerosis. The only abnormalities observed occurred during the quantitative sensory test presenting as severe widespread allodynia to cold and hot temperatures and during Laser Evoked Potentials shown as a dysfunctional pattern for central processing of nociceptive data. Gait analysis showed that parameters were in the norms. Considering these different tests and the excellent progression of the patient's gait and general posture, we must envision that the fibromyalgia syndrome hypothesis remained the most likely one. The generalized dystonia was probably due to the patient's analgesic protective attitude. The actual therapy is still based on the biopsychosocial approach. Copyright © 2011 Elsevier Masson SAS. All rights reserved.
Motor strategy patterns study of diabetic neuropathic individuals while walking. A wavelet approach.
Sacco, I C N; Hamamoto, A N; Onodera, A N; Gomes, A A; Weiderpass, H A; Pachi, C G F; Yamamoto, J F; von Tscharner, V
2014-07-18
The aim of this study was to investigate muscle׳s energy patterns and spectral properties of diabetic neuropathic individuals during gait cycle using wavelet approach. Twenty-one diabetic patients diagnosed with peripheral neuropathy, and 21 non-diabetic individuals were assessed during the whole gait cycle. Activation patterns of vastus lateralis, medial gastrocnemius and tibialis anterior were studied by means of bipolar surface EMG. The signal׳s energy and frequency were compared between groups using t-test. The energy was compared in each frequency band (7-542 Hz) using ANOVAs for repeated measures for each group and each muscle. The diabetic individuals displayed lower energies in lower frequency bands for all muscles and higher energies in higher frequency bands for the extensors׳ muscles. They also showed lower total energy of gastrocnemius and a higher total energy of vastus, considering the whole gait cycle. The overall results suggest a change in the neuromuscular strategy of the main extensor muscles of the lower limb of diabetic patients to compensate the ankle extensor deficit to propel the body forward and accomplish the walking task. Copyright © 2014 Elsevier Ltd. All rights reserved.
2009-01-01
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. PMID:19380288
Serrao, Mariano; Chini, Giorgia; Iosa, Marco; Casali, Carlo; Morone, Giovanni; Conte, Carmela; Bini, Fabiano; Marinozzi, Franco; Coppola, Gianluca; Pierelli, Francesco; Draicchio, Francesco; Ranavolo, Alberto
2017-10-01
The harmony of the human gait was recently found to be related to the golden ratio value (ϕ). The ratio between the duration of the stance and that of the swing phases of a gait cycle was in fact found to be close to ϕ, which implies that, because of the fractal property of autosimilarity of that number, the gait ratios stride/stance, stance/swing, swing/double support, were not significantly different from one another. We studied a group of patients with cerebellar ataxia to investigate how the differences between their gait ratios and the golden ratio are related to efficiency and stability of their gait, assessed by energy expenditure and stride-to-stride variability, respectively. The gait of 28 patients who were affected by degenerative cerebellar ataxia and of 28 healthy controls was studied using a stereophotogrammetric system. The above mentioned gait ratios, the energy expenditure estimated using the pelvis reconstructed method and the gait variability in terms of the stride length were computed, and their relationships were analyzed. Matching procedures have also been used to avoid multicollinearity biases. The gait ratio values of the patients were farther from the controls (and hence from ϕ), even in speed matched conditions (P=0.011, Cohen's D=0.76), but not when the variability and energy expenditure were matched between the two groups (Cohen's D=0.49). In patients with cerebellar ataxia, the farther the stance-swing ratio was from ϕ, the larger the total mechanical work (R 2 adj =0.64). Further, a significant positive correlation was observed between the difference of the gait ratio from the golden ratio and the severity of the disease (R=0.421, P=0.026). Harmony of gait appears to be a benchmark of physiological gait leading to physiological energy recovery and gait reliability. Neurorehabilitation of patients with ataxia might benefit from the restoration of harmony of their locomotor patterns. Copyright © 2017. Published by Elsevier Ltd.
Lambert, C S; Philpot, R M; Engberg, M E; Johns, B E; Wecker, L
2015-09-15
Studies have demonstrated that administration of the neuronal nicotinic receptor agonist varenicline to rats with olivocerebellar lesions attenuates balance deficits on a rotorod and balance beam, but the effects of this drug on gait deficits have not been investigated. To accomplish this, male Sprague-Dawley rats were trained to walk on a motorized treadmill at 25 and 35 cm/s and baseline performance determined; both temporal and spatial gait parameters were analyzed. A principal component analysis (PCA) was used to identify the key components of gait, and the cumulative gait index (CGI) was calculated, representing deviations from prototypical gait patterns. Subsequently, animals either remained as non-lesioned controls or received injections of 3-acetylpyridine (3-AP)/nicotinamide to destroy the climbing fibers innervating Purkinje cells. The gait of the non-lesioned group was assessed weekly to monitor changes in the normal population, while the gait of the lesioned group was assessed 1 week following 3-AP administration, and weekly following the daily administration of saline or varenicline (0.3, 1.0, or 3.0mg free base/kg) for 2 weeks. Non-lesioned animals exhibited a 60-70% increased CGI over time due to increases in temporal gait measures, whereas lesioned animals exhibited a nearly 3-fold increased CGI as a consequence of increases in spatial measures. Following 2 weeks of treatment with the highest dose of varenicline (3.0mg free base/kg), the swing duration of lesioned animals normalized, and stride duration, stride length and step angle in this population did not differ from the non-lesioned population. Thus, varenicline enabled animals to compensate for their impairments and rectify the timing of the gait cycle. Copyright © 2015 Elsevier B.V. All rights reserved.
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.
Debi, R; Elbaz, A; Mor, A; Kahn, G; Peskin, B; Beer, Y; Agar, G; Morag, G; Segal, G
2017-06-01
The purpose of the current study was to compare the gait patterns in patients with three differing knee pathologies - knee osteoarthritis (OA), degenerative meniscal lesion (DML) and spontaneous osteonecrosis of the knee (SONK) and a group of healthy controls. A simple gait test will detect differences between different knee pathologies. Forty-seven patients with bilateral knee OA, 47 patients with DML, 28 patients with SONK and 27 healthy controls were included in this analysis. Patients underwent a spatiotemporal gait assessment and were asked to complete the Western Ontario and McMaster University (WOMAC) Index and the Short-Form (SF)-36 Health Survey. ANOVA tests, followed by Bonferroni multiple comparison tests and the Chi 2 tests were performed for continuous and categorical variables, respectively. Significant differences were found for all gait measures and clinical questionnaires between healthy controls and all knee conditions. Patients with SONK differed from patients with bilateral knee OA and DML in all gait measures and clinical questionnaires, except for WOMAC subscales. There were no significant differences between patients with bilateral knee OA and patients with DML. Symmetry was also examined and revealed asymmetry in some gait parameters in patients with SONK and DML. Based on the differences in gait parameters that were found in the current study, adding an objective functional spatiotemporal gait test may assist in the diagnostic process of knee pathologies. Case Control study Level III. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
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.
Forneris, E; Andreacchio, A; Pollio, B; Mannucci, C; Franchini, M; Mengoli, C; Pagliarino, M; Messina, M
2016-05-01
To investigate the functional status in haemophilia patients referred to an Italian paediatric haemophilia centre using gait analysis, verifying any differences between mild, moderate or severe haemophilia at a functional level. Forty-two patients (age 4-18) presenting to the Turin Paediatric Haemophilia Centre who could walk independently were included. Therapy included prophylaxis (n = 21), on-demand (n = 17) or immune tolerance induction + inhibitor (n = 4). Patients performed a test of gait analysis. Temporal, spatial and kinematic parameters were calculated for patient subgroups by disease severity and background treatment, and compared with normal values. Moderate (35.7%) or severe (64.3%) haemophilia patients showed obvious variations from normal across a variety of temporal and spatial gait analysis parameters, including step speed and length, double support, swing phase, load asymmetry, stance phase, swing phase and speed. Kinematic parameters were characterized by frequent foot external rotation with deficient plantar flexion during the stance phase, retropelvic tilt, impaired power generation distally and reduced ground reaction forces. Both Gait Deviation Index and Gait Profile Score values for severe haemophilia patients indicated abnormal gait parameters, which were worst in patients with a history of past or current use of inhibitors and those receiving on-demand therapy. Functional evaluation identified changes in gait pattern in patients with severe and moderate haemophilia, compared with normal values. Gait analysis may be a useful tool to facilitate early diagnosis of joint damage, prevent haemophilic arthropathy, design a personalized rehabilitative treatment and monitor functional status over time. © 2016 John Wiley & Sons Ltd.
Reliability and validity of gait analysis by android-based smartphone.
Nishiguchi, Shu; Yamada, Minoru; Nagai, Koutatsu; Mori, Shuhei; Kajiwara, Yuu; Sonoda, Takuya; Yoshimura, Kazuya; Yoshitomi, Hiroyuki; Ito, Hiromu; Okamoto, Kazuya; Ito, Tatsuaki; Muto, Shinyo; Ishihara, Tatsuya; Aoyama, Tomoki
2012-05-01
Smartphones are very common devices in daily life that have a built-in tri-axial accelerometer. Similar to previously developed accelerometers, smartphones can be used to assess gait patterns. However, few gait analyses have been performed using smartphones, and their reliability and validity have not been evaluated yet. The purpose of this study was to evaluate the reliability and validity of a smartphone accelerometer. Thirty healthy young adults participated in this study. They walked 20 m at their preferred speeds, and their trunk accelerations were measured using a smartphone and a tri-axial accelerometer that was secured over the L3 spinous process. We developed a gait analysis application and installed it in the smartphone to measure the acceleration. After signal processing, we calculated the gait parameters of each measurement terminal: peak frequency (PF), root mean square (RMS), autocorrelation peak (AC), and coefficient of variance (CV) of the acceleration peak intervals. Remarkable consistency was observed in the test-retest reliability of all the gait parameter results obtained by the smartphone (p<0.001). All the gait parameter results obtained by the smartphone showed statistically significant and considerable correlations with the same parameter results obtained by the tri-axial accelerometer (PF r=0.99, RMS r=0.89, AC r=0.85, CV r=0.82; p<0.01). Our study indicates that the smartphone with gait analysis application used in this study has the capacity to quantify gait parameters with a degree of accuracy that is comparable to that of the tri-axial accelerometer.
Luu, Trieu Phat; He, Yongtian; Brown, Samuel; Nakagome, Sho; Contreras-Vidal, Jose L.
2016-01-01
The control of human bipedal locomotion is of great interest to the field of lower-body brain computer interfaces (BCIs) for rehabilitation of gait. While the feasibility of a closed-loop BCI system for the control of a lower body exoskeleton has been recently shown, multi-day closed-loop neural decoding of human gait in a virtual reality (BCI-VR) environment has yet to be demonstrated. In this study, we propose a real-time closed-loop BCI that decodes lower limb joint angles from scalp electroencephalography (EEG) during treadmill walking to control the walking movements of a virtual avatar. Moreover, virtual kinematic perturbations resulting in asymmetric walking gait patterns of the avatar were also introduced to investigate gait adaptation using the closed-loop BCI-VR system over a period of eight days. Our results demonstrate the feasibility of using a closed-loop BCI to learn to control a walking avatar under normal and altered visuomotor perturbations, which involved cortical adaptations. These findings have implications for the development of BCI-VR systems for gait rehabilitation after stroke and for understanding cortical plasticity induced by a closed-loop BCI system. PMID:27713915
Muscle Activation during Gait in Children with Duchenne Muscular Dystrophy.
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.
Mollaei, Nafiseh; Bicho, Estela; Sousa, Nuno; Gago, Miguel Fernandes
2017-01-01
Imbalance and tripping over obstacles as a result of altered gait in older adults, especially in patients with Parkinson's disease (PD), are one of the most common causes of falls. During obstacle crossing, patients with PD modify their behavior in order to decrease the mechanical demands and enhance dynamic stability. Various descriptions of dynamic traits of gait that have been collected over longer periods, probably better synthesize the underlying structure and pattern of fluctuations in gait and can be more sensitive markers of aging or early neurological dysfunction and increased risk of falls. This confirmation challenges the clinimetric of different protocols and paradigms used for gait analysis up till now, in particular when analyzing obstacle crossing. The authors here present a critical review of current knowledge concerning the interplay between the cognition and gait in aging and PD, emphasizing the differences in gait behavior and adaptability while walking over different and challenging obstacle paradigms, and the implications of obstacle negotiation as a predictor of falls. Some evidence concerning the effectiveness of future rehabilitation protocols on reviving obstacle crossing behavior by trial and error relearning, taking advantage of dual-task paradigms, physical exercise, and virtual reality have been put forward in this article.
Effects of visual focus and gait speed on walking balance in the frontal plane.
Goodworth, Adam; Perrone, Kathryn; Pillsbury, Mark; Yargeau, Michelle
2015-08-01
We investigated how head position and gait speed influenced frontal plane balance responses to external perturbations during gait. Thirteen healthy participants walked on a treadmill at three different gait speeds. Visual conditions included either focus downward on lower extremities and walking surface only or focus forward on a stationary scene with horizontal and vertical lines. The treadmill was positioned on a platform that was stationary (non-perturbed) or moving in a pattern that appeared random to the subjects (perturbed). In non-perturbed walking, medial-lateral upper body motion was very similar between visual conditions. However, in perturbed walking, there was significantly less body motion when focus was on the stationary visual scene, suggesting visual feedback of stationary vertical and horizontal cues are particularly important when balance is challenged. Sensitivity of body motion to perturbations was significantly decreased by increasing gait speed, suggesting that faster walking was less sensitive to frontal plane perturbations. Finally, our use of external perturbations supported the idea that certain differences in balance control mechanisms can only be detected in more challenging situations, which is an important consideration for approaches to investigating sensory contribution to balance during gait. Copyright © 2015 Elsevier B.V. All rights reserved.
Gait alterations to effectively reduce hip contact forces.
Wesseling, Mariska; de Groote, Friedl; Meyer, Christophe; Corten, Kristoff; Simon, Jean-Pierre; Desloovere, Kaat; Jonkers, Ilse
2015-07-01
Patients with hip pathology present alterations in gait which have an effect on joint moments and loading. In knee osteoarthritic patients, the relation between medial knee contact forces and the knee adduction moment are currently being exploited to define gait retraining strategies to effectively reduce pain and disease progression. However, the relation between hip contact forces and joint moments has not been clearly established. Therefore, this study aims to investigate the effect of changes in hip and pelvis kinematics during gait on internal hip moments and contact forces which is calculated using muscle driven simulations. The results showed that frontal plane kinetics have the largest effect on hip contact forces. Given the high correlation between the change in hip adduction moment and contact force at initial stance (R(2) = 0.87), this parameter can be used to alter kinematics and predict changes in contact force. At terminal stance the hip adduction and flexion moment can be used to predict changes in contact force (R(2) = 0.76). Therefore, gait training that focuses on decreasing hip adduction moments, a wide base gait pattern, has the largest potential to reduce hip contact forces. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.
“Gunslinger’s gait”: a new cause of unilaterally reduced arm swing
Araújo, Rui; Ferreira, Joaquim J; Antonini, Angelo
2015-01-01
Objective To postulate a new possible cause of a unilaterally reduced arm swing in addition to the known medical conditions such as shoulder pathology, Erb’s palsy, stroke, and Parkinson’s disease. Methods Analysis of YouTube videos depicting the gait of highly ranked Russian officials. Results We found a similar walking pattern in President Vladimir Putin, Prime Minister Dmitry Medvedev and three other highly ranked Russian officials, all presenting with a consistently reduced right arm swing in the absence of other overt neurological abnormalities. Conclusions We propose that this new gait pattern, which we term “gunslinger’s gait,” may result from a behavioural adaptation, possibly triggered by KGB or other forms of weapons training where trainees are taught to keep their right hand close to the chest while walking, allowing them to quickly draw a gun when faced with a foe. This should be included in the differential diagnosis of a unilaterally reduced arm swing. PMID:26666758
A PDF-based classification of gait cadence patterns in patients with amyotrophic lateral sclerosis.
Wu, Yunfeng; Ng, Sin Chun
2010-01-01
Amyotrophic lateral sclerosis (ALS) is a type of neurological disease due to the degeneration of motor neurons. During the course of such a progressive disease, it would be difficult for ALS patients to regulate normal locomotion, so that the gait stability becomes perturbed. This paper presents a pilot statistical study on the gait cadence (or stride interval) in ALS, based on the statistical analysis method. The probability density functions (PDFs) of stride interval were first estimated with the nonparametric Parzen-window method. We computed the mean of the left-foot stride interval and the modified Kullback-Leibler divergence (MKLD) from the PDFs estimated. The analysis results suggested that both of these two statistical parameters were significantly altered in ALS, and the least-squares support vector machine (LS-SVM) may effectively distinguish the stride patterns between the ALS patients and healthy controls, with an accurate rate of 82.8% and an area of 0.87 under the receiver operating characteristic curve.
Caetano, Maria Joana D; Lord, Stephen R; Schoene, Daniel; Pelicioni, Paulo H S; Sturnieks, Daina L; Menant, Jasmine C
2016-05-01
A large proportion of falls in older people occur when walking. Limitations in gait adaptability might contribute to tripping; a frequently reported cause of falls in this group. To evaluate age-related changes in gait adaptability in response to obstacles or stepping targets presented at short notice, i.e.: approximately two steps ahead. Fifty older adults (aged 74±7 years; 34 females) and 21 young adults (aged 26±4 years; 12 females) completed 3 usual gait speed (baseline) trials. They then completed the following randomly presented gait adaptability trials: obstacle avoidance, short stepping target, long stepping target and no target/obstacle (3 trials of each). Compared with the young, the older adults slowed significantly in no target/obstacle trials compared with the baseline trials. They took more steps and spent more time in double support while approaching the obstacle and stepping targets, demonstrated poorer stepping accuracy and made more stepping errors (failed to hit the stepping targets/avoid the obstacle). The older adults also reduced velocity of the two preceding steps and shortened the previous step in the long stepping target condition and in the obstacle avoidance condition. Compared with their younger counterparts, the older adults exhibited a more conservative adaptation strategy characterised by slow, short and multiple steps with longer time in double support. Even so, they demonstrated poorer stepping accuracy and made more stepping errors. This reduced gait adaptability may place older adults at increased risk of falling when negotiating unexpected hazards. Copyright © 2016 Elsevier B.V. All rights reserved.
The role of a vertical reference point in changing gait regulation in cricket run-ups.
Greenwood, Daniel; Davids, Keith; Renshaw, Ian
2016-10-01
The need to identify information sources which facilitate a functional coupling of perception and action in representative practice contexts is an important challenge for sport scientists and coaches. The current study investigated the role of visual information in regulating athlete gait behaviours during a locomotor pointing task in cricket. Integration of experiential knowledge of elite coaches and theoretical understanding from previous empirical research led us to investigate whether the presence of an umpire would act as a vertical informational constraint that could constrain the emergent coordination tendencies of cricket bowlers' run-up patterns. To test this idea, umpire presence was manipulated during run-ups of 10 elite medium-fast bowlers. As hypothesised, removal of the umpire from the performance environment did not result in an inability to regulate gait to intercept a target, however, the absence of this informational constraint resulted in the emergence of different movement patterns in participant run-ups. Significantly lower standard deviation values of heel-to-crease distances were observed in the umpire condition at multiple steps, compared to performance in the no-umpire condition. Manipulation of this informational constraint altered gait regulation of participants, offering a mechanism to understand how perception-action couplings can be varied during performance in locomotor pointing tasks in sport.
Velayutham, Selva Ganapathy; Chandra, Sadanandavalli Retnaswami; Bharath, Srikala; Shankar, Ravi Girikamatha
2017-01-01
Alzhiemers disease and Frontotemporal dementia are common neurodegenerative dementias with a wide prevalence. Falls are a common cause of morbidity in these patients. Identifying subclinical involvement of these parameters might serve as a tool in differential analysis of these distinct parameters involved in these conditions and also help in planning preventive strategies to prevent falls. Eight patients in age and gender matched patients in each group were compared with normal controls. Standardizes methods of gait and balance aseesment were done in all persons. Results revealed subclinical involvement of gait and balancesin all groups specially during divided attention. The parameters were significantly more affected in patients. Patients with AD and FTD had involement of over all ambulation index balance more affected in AD patients FTD patients showed step cycle, stride length abnormalities. There is balance and gait involvement in normal ageing as well as patients with AD and FTD. The pattern of involvement in AD correlates with WHERE pathway involvement and FTD with frontal subcortical circuits involvement. Identification the differential patterns of involvement in subclinical stage might help to differentiate normal ageing and the different types of cortical dementias. This could serve as an additional biomarker and also assist in initiating appropriate training methods to prevent future falls.
Early Changes of Articular Cartilage and Subchondral Bone in The DMM Mouse Model of Osteoarthritis.
Fang, Hang; Huang, Lisi; Welch, Ian; Norley, Chris; Holdsworth, David W; Beier, Frank; Cai, Daozhang
2018-02-12
To examine the early changes of articular cartilage and subchondral bone in the DMM mouse model of osteoarthritis, mice were subjected to DMM or SHAM surgery and sacrificed at 2-, 5- and 10-week post-surgery. Catwalk gait analyses, Micro-Computed Tomography, Toluidine Blue, Picrosirius Red and Tartrate-Resistant Acid Phosphatase (TRAP) staining were used to investigate gait patterns, joint morphology, subchondral bone, cartilage, collagen organization and osteoclasts activity, respectively. Results showed OA progressed over 10-week time-course. Gait disparity occurred only at 10-week post-surgery. Osteophyte formed at 2-week post-surgery. BMDs of DMM showed no statistical differences comparing to SHAM at 2 weeks, but BV/TV is much higher in DMM mice. Increased BMD was clearly found at 5- and 10-week post-surgery in DMM mice. TRAP staining showed increased osteoclast activity at the site of osteophyte formation of DMM joints at 5- and 10-week time points. These results showed that subchondral bone turnover might occurred earlier than 2 weeks in this mouse DMM model. Gait disparity only occurred at later stage of OA in DMM mice. Notably, patella dislocation could occur in some of the DMM mice and cause a different pattern of OA in affected knee.
Invariant hip moment pattern while walking with a robotic hip exoskeleton
Lewis, Cara L.; Ferris, Daniel P.
2011-01-01
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 minutes of the powered condition and the unpowered condition. After completing three 30-minute 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. PMID:21333995
van Bloemendaal, Maijke; Bus, Sicco A; de Boer, Charlotte E; Nollet, Frans; Geurts, Alexander C H; Beelen, Anita
2016-10-01
Many stroke survivors suffer from paresis of lower limb muscles, resulting in compensatory gait patterns characterised by asymmetries in spatial and temporal parameters and reduced walking capacity. Functional electrical stimulation has been used to improve walking capacity, but evidence is mostly limited to the orthotic effects of peroneal functional electrical stimulation in the chronic phase after stroke. The aim of this study is to investigate the therapeutic effects of up to 10 weeks of multi-channel functional electrical stimulation (MFES)-assisted gait training on the restoration of spatiotemporal gait symmetry and walking capacity in subacute stroke patients. In a proof-of-principle study with a randomised controlled design, 40 adult patients with walking deficits who are admitted for inpatient rehabilitation within 31 days since the onset of stroke are randomised to either MFES-assisted gait training or conventional gait training. Gait training is delivered in 30-minute sessions each workday for up to 10 weeks. The step length symmetry ratio is the primary outcome. Blinded assessors conduct outcome assessments at baseline, every 2 weeks during the intervention period, immediately post intervention and at 3-month follow-up. This study aims to provide preliminary evidence for the feasibility and effectiveness of MFES-assisted gait rehabilitation early after stroke. Results will inform the design of a larger multi-centre trial. This trial is registered at the Netherlands Trial Register (number NTR4762 , registered 28 August 2014).
An apparent contradiction: increasing variability to achieve greater precision?
Rosenblatt, Noah J; Hurt, Christopher P; Latash, Mark L; Grabiner, Mark D
2014-02-01
To understand the relationship between variability of foot placement in the frontal plane and stability of gait patterns, we explored how constraining mediolateral foot placement during walking affects the structure of kinematic variance in the lower-limb configuration space during the swing phase of gait. Ten young subjects walked under three conditions: (1) unconstrained (normal walking), (2) constrained (walking overground with visual guides for foot placement to achieve the measured unconstrained step width) and, (3) beam (walking on elevated beams spaced to achieve the measured unconstrained step width). The uncontrolled manifold analysis of the joint configuration variance was used to quantify two variance components, one that did not affect the mediolateral trajectory of the foot in the frontal plane ("good variance") and one that affected this trajectory ("bad variance"). Based on recent studies, we hypothesized that across conditions (1) the index of the synergy stabilizing the mediolateral trajectory of the foot (the normalized difference between the "good variance" and "bad variance") would systematically increase and (2) the changes in the synergy index would be associated with a disproportionate increase in the "good variance." Both hypotheses were confirmed. We conclude that an increase in the "good variance" component of the joint configuration variance may be an effective method of ensuring high stability of gait patterns during conditions requiring increased control of foot placement, particularly if a postural threat is present. Ultimately, designing interventions that encourage a larger amount of "good variance" may be a promising method of improving stability of gait patterns in populations such as older adults and neurological patients.
Stride-related rein tension patterns in walk and trot in the ridden horse.
Egenvall, Agneta; Roepstorff, Lars; Eisersiö, Marie; Rhodin, Marie; van Weeren, René
2015-12-30
The use of tack (equipment such as saddles and reins) and especially of bits because of rein tension resulting in pressure in the mouth is questioned because of welfare concerns. We hypothesised that rein tension patterns in walk and trot reflect general gait kinematics, but are also determined by individual horse and rider effects. Six professional riders rode three familiar horses in walk and trot. Horses were equipped with rein tension meters logged by inertial measurement unit technique. Left and right rein tension data were synchronized with the gait. Stride split data (0-100 %) were analysed using mixed models technique to elucidate the left/right rein and stride percentage interaction, in relation to the exercises performed. In walk, rein tension was highest at hindlimb stance. Rein tension was highest in the suspension phase at trot, and lowest during the stance phase. In rising trot there was a significant difference between the two midstance phases, but not in sitting trot. When turning in trot there was a significant statistical association with the gait pattern with the tension being highest in the inside rein when the horse was on the outer fore-inner hindlimb diagonal. Substantial between-rider variation was demonstrated in walk and trot and between-horse variation in walk. Biphasic rein tensions patterns during the stride were found mainly in trot.
Doherty, Cailbhe; Bleakley, Chris; Hertel, Jay; Caulfield, Brian; Ryan, John; Delahunt, Eamonn
2015-02-01
Laboratory analyses of chronic ankle instability populations during gait have elucidated a number of anomalous movement patterns. No current research exists analysing these movement patterns in a group in the acute phase of lateral ankle sprain (LAS) injury. It is possible that participants with an acute LAS display movement patterns continuous with their chronically impaired counterparts. Sixty eight participants with acute LAS and nineteen non-injured participants completed five gait trials. 3D lower extremity temporal kinematic and kinetic data were collected from 200 ms pre- to 200 ms post-heel strike (period 1) and from 200 ms pre- to 200 ms post-toe off (period 2). During period 1, the LAS group displayed increased knee flexion with increased net extensor pattern at the knee joint, increased ankle inversion with a greater inversion moment, and reduced ankle plantar flexion, compared to the non-injured control group. During period 2, the LAS group displayed decreased hip extension with a decrease in the flexor moment at the hip, and decreased ankle plantar flexion with a decrease in the net plantar flexion moment, compared to the non-injured control group. These results indicate that participants with acute LAS display coordination strategies which may play a role in the onset of chronicity or recovery. Copyright © 2014 Elsevier Ltd. All rights reserved.
Rossi, Stefano; Colazza, Alessandra; Petrarca, Maurizio; Castelli, Enrico; Cappa, Paolo; Krebs, Hermano Igo
2013-01-01
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.
Sanz-Mengibar, Jose Manuel; Altschuck, Natalie; Sanchez-de-Muniain, Paloma; Bauer, Christian; Santonja-Medina, Fernando
2017-04-01
To understand whether there is a trunk postural control threshold in the sagittal plane for the transition between the Gross Motor Function Classification System (GMFCS) levels measured with 3-dimensional gait analysis. Kinematics from 97 children with spastic bilateral cerebral palsy from spine angles according to Plug-In Gait model (Vicon) were plotted relative to their GMFCS level. Only average and minimum values of the lumbar spine segment correlated with GMFCS levels. Maximal values at loading response correlated independently with age at all functional levels. Average and minimum values were significant when analyzing age in combination with GMFCS level. There are specific postural control patterns in the average and minimum values for the position between trunk and pelvis in the sagittal plane during gait, for the transition among GMFCS I-III levels. Higher classifications of gross motor skills correlate with more extended spine angles.
LeMoyne, Robert; Mastroianni, Timothy
2016-08-01
Natural gait consists of synchronous and rhythmic patterns for both the lower and upper limb. People with hemiplegia can experience reduced arm swing, which can negatively impact the quality of gait. Wearable and wireless sensors, such as through a smartphone, have demonstrated the ability to quantify various features of gait. With a software application the smartphone (iPhone) can function as a wireless gyroscope platform capable of conveying a gyroscope signal recording as an email attachment by wireless connectivity to the Internet. The gyroscope signal recordings of the affected hemiplegic arm with reduced arm swing arm and the unaffected arm are post-processed into a feature set for machine learning. Using a multilayer perceptron neural network a considerable degree of classification accuracy is attained to distinguish between the affected hemiplegic arm with reduced arm swing arm and the unaffected arm.
FreeWalker: a smart insole for longitudinal gait analysis.
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.
Locomotor-respiratory coupling during axillary crutch ambulation.
Hurst, C A; Kirby, R L; MacLeod, D A
2001-11-01
To test the hypotheses that locomotor-respiratory coupling occurs in humans using axillary crutches in a swing-through ambulation pattern and that expiration occurs during crutch-stance phase during locomotor-respiratory coupling. Eighteen able-bodied persons were trained in one-footed swing-through gait with axillary crutches. Then, as subjects walked at "somewhat hard" speeds (Borg) on a motorized treadmill for 5 min, we recorded signals from a crutch pressure switch and a mouthpiece-mounted thermocouple. Coupling was defined as being present when the onset of inspiration varied by < or = 5% with respect to the onset of the crutch gait cycle for a minimum of 10 consecutive gait cycles and when there was no drift on a raster plot of the respiratory phases relative to the onset of the gait cycle. Ten (56%) of the 18 subjects exhibited locomotor-respiratory coupling on 1-4 occasions each, with episodes lasting 11.3-148 sec. In 17 (89%) of the 19 episodes of 1:1 locomotor-respiratory coupling, expiration occurred during the crutch-stance phase of the gait cycle and inspiration occurred during crutch swing. Transient 1:1 locomotor-respiratory coupling occurs in many able-bodied subjects ambulating with axillary crutches and a swing-through gait. Expiration is most often associated with the crutch-stance phase of the gait cycle. This study may have implications for training axillary crutch users.
Seyed, Mohammadali Rahmati; Mostafa, Rostami; Borhan, Beigzadeh
2018-04-27
The parametric optimization techniques have been widely employed to predict human gait trajectories; however, their applications to reveal the other aspects of gait are questionable. The aim of this study is to investigate whether or not the gait prediction model is able to justify the movement trajectories for the higher average velocities. A planar, seven-segment model with sixteen muscle groups was used to represent human neuro-musculoskeletal dynamics. At first, the joint angles, ground reaction forces (GRFs) and muscle activations were predicted and validated for normal average velocity (1.55 m/s) in the single support phase (SSP) by minimizing energy expenditure, which is subject to the non-linear constraints of the gait. The unconstrained system dynamics of extended inverse dynamics (USDEID) approach was used to estimate muscle activations. Then by scaling time and applying the same procedure, the movement trajectories were predicted for higher average velocities (from 2.07 m/s to 4.07 m/s) and compared to the pattern of movement with fast walking speed. The comparison indicated a high level of compatibility between the experimental and predicted results, except for the vertical position of the center of gravity (COG). It was concluded that the gait prediction model can be effectively used to predict gait trajectories for higher average velocities.
Altered vision destabilizes gait in older persons.
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.
Springer, Shmuel; Friedman, Itamar; Ohry, Avi
2018-01-01
Background Age-related changes in coordinated movement pattern of the thorax and pelvis may be one of the factors contributing to fall risk. This report describes the feasibility of using a new thoracopelvic assisted movement device to improve gait and balance in an elderly population with increased risk for falls. Methods In this case series, 19 older adults were recruited from an assisted living facility. All had gait difficulties (gait speed <1.0 m/s) and history of falls. Participants received 12 training sessions with the thoracopelvic assisted movement device. Functional performance was measured before, during (after 6 sessions), and after the 12 sessions. Outcomes measures were Timed Up and Go, Functional Reach Test, and the 10-meter Walk Test. Changes in outcomes were calculated for each participant in the context of minimal detectable change (MDC) values. Results More than 25% of participants showed changes >MDC in their clinical measures after 6 treatment sessions, and more than half improved >MDC after 12 sessions. Six subjects (32%) improved their Timed Up and Go time by >4 seconds after 6 sessions, and 10 (53%) after 12 sessions. After the intervention, 4 subjects (21%) improved their 10-meter Walk Test velocity from limited community ambulation (0.4–0.8 m/s) to functional community ambulation (>0.8 m/s). Conclusion Thoracopelvic assisted movement training that mimics normal walking pattern may have clinical implications, by improving skills that enhance balance and gait function. Additional randomized, controlled studies are required to examine the effects of this intervention on larger cohorts with a variety of subjects.
Vendrely, Ann; Messmer, Eric; Moseley, Jennifer
2012-04-01
Fear of falling is a common concern among adults over age 65, which results in decreased activity levels. Cognitive-behavioral therapy (CBT) uses psychological techniques to redirect negative cognitive, emotional, or behavioral affects for improvement of self-efficacy and reduced fear of falling. The purpose of this case study is to describe the integration of CBT into the physical therapy (PT) management of a middle-aged male with fear of falling and difficulty walking. The single subject was a 58-year-old male with complaints of frequently losing his balance, feeling unstable while walking, and requiring the use of a walker to ambulate. During the initial PT examination his primary impairment was difficulty ambulating in open spaces. Dynamic Gait Index (DGI) was 8/24 and the Modified Falls Efficacy Score (MFES) was 6.36/10. The interventions began with a general lower extremity strengthening program, balance exercises, and gait training. At visit 9, CBT techniques of cognitive restructuring were added. Visualization of correct gait patterns was added to the program during visit 10, which continued until discharge after visit 14. Measurements on the DGI improved to 23/24 and MFES improved to 9.43/10 at discharge. Gait pattern improved with the ability to ambulate indoors without an assistive device and using only a straight cane for community ambulation. The use of CBT is well documented as a group intervention for older adults with fear of falling, but CBT techniques may also be helpful for younger adults with fear of falling.
Gait dynamics in Pisa syndrome and Camptocormia: The role of stride length and hip kinematics.
Tramonti, C; Di Martino, S; Unti, E; Frosini, D; Bonuccelli, U; Rossi, B; Ceravolo, R; Chisari, C
2017-09-01
This is an observational cross-sectional study evaluating gait dynamics in patients with Parkinson's Disease (PD) and severe postural deformities, PD without axial deviations and healthy subjects. Ten PS individuals with Pisa syndrome (PS) and nine subjects with Camptocormia (CC) performed 3-D Gait Analysis and were evaluated with walking and balance scales. Correlations with clinical and functional scales were investigated. Spatio-temporal and kinematic data were compared to ten PD subjects without postural deformities (PP) and ten healthy matched individuals (CG). Data obtained showed decreased walking velocity, stride and step length in PP, PS and CC groups compared to controls. The correlation analysis showed that stride and step length were associated with reduced functional abilities and disease severity in PS and CC groups. Kinematic data revealed marked reduction in range of movements (ROMs) at all lower-extremity joints in PS group. While, in CC group the main differences were pronounced in hip and knee joints. PS and CC groups presented a more pronounced reduction in hip articular excursion compared to PP subjects, revealing an increased hip flexion pattern during gait cycle. Moreover, the increased hip and knee flexion pattern adversely affected functional performance during walking tests. Results obtained provide evidence that step length, along with stride length, can be proposed as simple and clear indicators of disease severity and reduced functional abilities. The reduction of ROMs at hip joint represented an important mechanism contributing to decreased walking velocity, balance impairment and reduced gait performance in PD patients with postural deformities. Copyright © 2017 Elsevier B.V. All rights reserved.
Yoshida, Yuri; Mizner, Ryan L.; Snyder-Mackler, Lynn
2013-01-01
INTRODUCTION Quadriceps weakness is one of the primary post-operative impairments that persist long term for patients after total knee arthroplasty (TKA). We hypothesized that early gait muscle recruitment patterns of the quadriceps and hamstrings with diminished knee performance at 3 months after surgery would be related to long-term quadriceps strength at one year after TKA. METHODS Twenty-one subjects who underwent primary unilateral TKA and 14 age-matched healthy controls were analyzed. At three months after TKA, the maximum voluntary isometric contraction of quadriceps and a comprehensive gait analysis were performed. Quadriceps strength was assessed again at one year after surgery. RESULTS Quadriceps muscle recruitment of the operated limb was greater than the non-operated limb during the loading response of gait (p=0.03), but there were no significant differences in hamstring recruitment or co-contraction between limbs (p>0.05). There were significant differences in quadriceps muscle recruitment during gait between the non-operated limb of TKA group and healthy control group (p<0.05). The TKA group showed a significant inverse relationship between one year quadriceps strength and co-contraction (r = −0.543) and hamstring muscle recruitment (r = −0.480) during loading response at 3 months after TKA. CONCLUSIONS The results revealed a reverse relationship where stronger patients tended to demonstrate lower quadriceps recruitment at 3 months post-surgery that was not observed in the healthy peer group. The altered neuromuscular patterns of quadriceps and hamstrings during gait may influence chronic quadriceps strength in individuals after TKA. PMID:23352711
Gait COP trajectory of left side hip-dislocation and scoliotic patient using ankle-foot orthoses
NASA Astrophysics Data System (ADS)
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.
Interactive locomotion: Investigation and modeling of physically-paired humans while walking
Le Goff, Camille G.; Ijspeert, Auke Jan
2017-01-01
In spite of extensive studies on human walking, less research has been conducted on human walking gait adaptation during interaction with another human. In this paper, we study a particular case of interactive locomotion where two humans carry a rigid object together. Experimental data from two persons walking together, one in front of the other, while carrying a stretcher-like object is presented, and the adaptation of their walking gaits and coordination of the foot-fall patterns are analyzed. It is observed that in more than 70% of the experiments the subjects synchronize their walking gaits; it is shown that these walking gaits can be associated to quadrupedal gaits. Moreover, in order to understand the extent by which the passive dynamics can explain this synchronization behaviour, a simple 2D model, made of two-coupled spring-loaded inverted pendulums, is developed, and a comparison between the experiments and simulations with this model is presented, showing that with this simple model we are able to reproduce some aspects of human walking behaviour when paired with another human. PMID:28877161
A Feasibility Study of View-independent Gait Identification
2012-03-01
ice skates . For walking, the footprint records for single pixels form clusters that are well separated in space and time. (Any overlap of contact...Pattern Recognition 2007, 1-8. Cheng M-H, Ho M-F & Huang C-L (2008), "Gait Analysis for Human Identification Through Manifold Learning and HMM... Learning and Cybernetics 2005, 4516-4521 Moeslund T B & Granum E (2001), "A Survey of Computer Vision-Based Human Motion Capture", Computer Vision
Shin, Hyung-Ik; Sung, Ki Hyuk; Chung, Chin Youb; Lee, Kyoung Min; Lee, Seung Yeol; Lee, In Hyeok
2016-01-01
Purpose This study investigated the correlation between isometric muscle strength, gross motor function, and gait parameters in patients with spastic cerebral palsy and to find which muscle groups play an important role for gait pattern in a flexed knee gait. Materials and Methods Twenty-four ambulatory patients (mean age, 10.0 years) with spastic cerebral palsy who were scheduled for single event multilevel surgery, including distal hamstring lengthening, were included. Preoperatively, peak isometric muscle strength was measured for the hip flexor, hip extensor, knee flexor, and knee extensor muscle groups using a handheld dynamometer, and three-dimensional (3D) gait analysis and gross motor function measure (GMFM) scoring were also performed. Correlations between peak isometric strength and GMFM, gait kinematics, and gait kinetics were analyzed. Results Peak isometric muscle strength of all muscle groups was not related to the GMFM score and the gross motor function classification system level. Peak isometric strength of the hip extensor and knee extensor was significantly correlated with the mean pelvic tilt (r=-0.588, p=0.003 and r=-0.436, p=0.033) and maximum pelvic obliquity (r=-0.450, p=0.031 and r=-0.419, p=0.041). There were significant correlations between peak isometric strength of the knee extensor and peak knee extensor moment in early stance (r=0.467, p=0.021) and in terminal stance (r=0.416, p=0.043). Conclusion There is no correlation between muscle strength and gross motor function. However, this study showed that muscle strength, especially of the extensor muscle group of the hip and knee joints, might play a critical role in gait by stabilizing pelvic motion and decreasing energy consumption in a flexed knee gait. PMID:26632404
Shin, Hyung Ik; Sung, Ki Hyuk; Chung, Chin Youb; Lee, Kyoung Min; Lee, Seung Yeol; Lee, In Hyeok; Park, Moon Seok
2016-01-01
This study investigated the correlation between isometric muscle strength, gross motor function, and gait parameters in patients with spastic cerebral palsy and to find which muscle groups play an important role for gait pattern in a flexed knee gait. Twenty-four ambulatory patients (mean age, 10.0 years) with spastic cerebral palsy who were scheduled for single event multilevel surgery, including distal hamstring lengthening, were included. Preoperatively, peak isometric muscle strength was measured for the hip flexor, hip extensor, knee flexor, and knee extensor muscle groups using a handheld dynamometer, and three-dimensional (3D) gait analysis and gross motor function measure (GMFM) scoring were also performed. Correlations between peak isometric strength and GMFM, gait kinematics, and gait kinetics were analyzed. Peak isometric muscle strength of all muscle groups was not related to the GMFM score and the gross motor function classification system level. Peak isometric strength of the hip extensor and knee extensor was significantly correlated with the mean pelvic tilt (r=-0.588, p=0.003 and r=-0.436, p=0.033) and maximum pelvic obliquity (r=-0.450, p=0.031 and r=-0.419, p=0.041). There were significant correlations between peak isometric strength of the knee extensor and peak knee extensor moment in early stance (r=0.467, p=0.021) and in terminal stance (r=0.416, p=0.043). There is no correlation between muscle strength and gross motor function. However, this study showed that muscle strength, especially of the extensor muscle group of the hip and knee joints, might play a critical role in gait by stabilizing pelvic motion and decreasing energy consumption in a flexed knee gait.
Psarakis, Michael; Greene, David; Moresi, Mark; Baker, Michael; Stubbs, Peter; Brodie, Matthew; Lord, Stephen; Hoang, Phu
2017-11-01
Gait impairment in people with Multiple Sclerosis results from neurological impairment, muscle weakness and reduced range of motion. Restrictions in passive ankle range of motion can result in abnormal heel-to-toe progression (weight transfer) and inefficient gait patterns in people with Multiple Sclerosis. The purpose of this study was to determine the associations between gait impairment, heel-to-toe progression and ankle range of motion in people with Multiple Sclerosis. Twelve participants with Multiple Sclerosis and twelve healthy age-matched participants were assessed. Spatiotemporal parameters of gait and individual footprint data were used to investigate group differences. A pressure sensitive walkway was used to divide each footprint into three phases (contact, mid-stance, propulsive) and calculate the heel-to-toe progression during the stance phase of gait. Compared to healthy controls, people with Multiple Sclerosis spent relatively less time in contact phase (7.8% vs 25.1%) and more time in the mid stance phase of gait (57.3% vs 33.7%). Inter-limb differences were observed in people with Multiple Sclerosis between the affected and non-affected sides for contact (7.8% vs 15.3%) and mid stance (57.3% and 47.1%) phases. Differences in heel-to-toe progression remained significant after adjusting for walking speed and were correlated with walking distance and ankle range of motion. Impaired heel-to-toe progression was related to poor ankle range of motion in people with Multiple Sclerosis. Heel-to-toe progression provided a sensitive measure for assessing gait impairments that were not detectable using standard spatiotemporal gait parameters. Copyright © 2017 Elsevier Ltd. All rights reserved.
Arellano-Martínez, Irma Tamara; Rodríguez-Reyes, Gerardo; Quiñones-Uriostegui, Ivet; Arellano-Saldaña, María Elena
2013-01-01
Cerebral palsy is the most common cause of disability among children. Parent's main concerns are the acquisition and improvement of gait. The aim of this study was to compare long term results of the effect of two modalities of gait training. Quantitative measurement of gait and clinical assessment of the gross motor function classification system and Modified Ashworth Scale were perfomed in 14 patients with Cerebral palsy -spastic hemiplegia and randomizedly assigned into two groups of treatment: the first one using a driven gait orthosis (Lokomat(®)) and the second a gait training a long a rail inside a hydrotherapy tank. Measurements and assessments, above described, were performed immediately and one year after the treatment concluded. Significant change was observed in the gross motor function classification system from II to I among children (p=0.042) and a positive correlation between the shape functional of the march and the gross motor function classification system (r = 0.54, p = 0.042). Patients on the Lokomat(®) training improved on gait symmetry over patients on the conventional therapy (p = 0.05). A year after, this intervention showed tendency to kept the gait patterns only on patients treated with the Lokomat(®) Benefit obtained with either modality was evident for both groups. However, residual effects observed on the Lokomat group, either in clinical assessment or gait parameters, were more promising than in the conventional therapy. Due to the size of the sample used in this study the results are not conclusive and more research must be done on this subject in long term time horizon.
Forner-Cordero, Arturo; Ackermann, Marko; de Lima Freitas, Mateus
2011-01-01
Perturbations during human gait such as a trip or a slip can result in a fall, especially among frail populations such as the elderly. In order to recover from a trip or a stumble during gait, humans perform different types of recovery strategies. It is very useful to uncover the mechanisms of the recovery to improve training methods for populations at risk of falling. Moreover, human recovery strategies could be applied to implement controllers for bipedal robot walker, as an application of biomimetic design. A biomechanical model of the response to a trip during gait might uncover the control mechanisms underlying the different recovery strategies and the adaptation of the responses found during the execution of successive perturbation trials. This paper introduces a model of stumble in the multibody system framework. This model is used to assess different feedforward strategies to recover from a trip. First of all, normal gait patterns for the musculoskeletal system model are obtained by solving an optimal control problem. Secondly, the reference gait is perturbed by the application of forces on the swinging foot in different ways: as an instantaneous inelastic collision of the foot with an obstacle, as an impulsive horizontal force or using a force curve measured experimentally during gait perturbation experiments. The influence of the type of perturbation, the timing of the collision with respect to the gait cycle, as well as of the coefficient of restitution was investigated previously. Finally, in order to test the effects of different muscle excitation levels on the initial phases of the recovery response, several muscle excitations were added to selected muscles of the legs, thus providing a simulation of the recovery reactions. These results pave the way for future analysis and modeling of the control mechanisms of gait.
McGibbon, Chris A; Krebs, David E; Parker, Stephen W; Scarborough, Donna M; Wayne, Peter M; Wolf, Steven L
2005-01-01
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 gait and reduced excessive hip compensation. The VR group's improvements, however, were not the result of lower extremity neuromuscular pattern changes. Lower-extremity MEE increases corresponded to attenuated forward trunk linear and angular movement in the VR group, suggesting better control of upper body motion to minimize loss of balance. These data support a growing body of evidence that Tai Chi may be a valuable complementary treatment for vestibular disorders. PMID:15717934
Performance of an inverted pendulum model directly applied to normal human gait.
Buczek, Frank L; Cooney, Kevin M; Walker, Matthew R; Rainbow, Michael J; Concha, M Cecilia; Sanders, James O
2006-03-01
In clinical gait analysis, we strive to understand contributions to body support and propulsion as this forms a basis for treatment selection, yet the relative importance of gravitational forces and joint powers can be controversial even for normal gait. We hypothesized that an inverted pendulum model, propelled only by gravity, would be inadequate to predict velocities and ground reaction forces during gait. Unlike previous ballistic and passive dynamic walking studies, we directly compared model predictions to gait data for 24 normal children. We defined an inverted pendulum from the average center-of-pressure to the instantaneous center-of-mass, and derived equations of motion during single support that allowed a telescoping action. Forward and inverse dynamics predicted pendulum velocities and ground reaction forces, and these were statistically and graphically compared to actual gait data for identical strides. Results of forward dynamics replicated those in the literature, with reasonable predictions for velocities and anterior ground reaction forces, but poor predictions for vertical ground reaction forces. Deviations from actual values were explained by joint powers calculated for these subjects. With a telescoping action during inverse dynamics, predicted vertical forces improved dramatically and gained a dual-peak pattern previously missing in the literature, yet expected for normal gait. These improvements vanished when telescoping terms were set to zero. Because this telescoping action is difficult to explain without muscle activity, we believe these results support the need for both gravitational forces and joint powers in normal gait. Our approach also begins to quantify the relative contributions of each.
Aging effect on step adjustments and stability control in visually perturbed gait initiation.
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 dual tasking on gait synchronization during over-ground side-by-side walking.
Zivotofsky, Ari Z; Bernad-Elazari, Hagar; Grossman, Pnina; Hausdorff, Jeffrey M
2018-06-01
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.
Ankle Training With a Robotic Device Improves Hemiparetic Gait After a Stroke
Forrester, Larry W.; Roy, Anindo; Krebs, Hermano Igo; Macko, Richard F.
2013-01-01
Background Task-oriented therapies such as treadmill exercise can improve gait velocity after stroke, but slow velocities and abnormal gait patterns often persist, suggesting a need for additional strategies to improve walking. Objectives To determine the effects of a 6-week visually guided, impedance controlled, ankle robotics intervention on paretic ankle motor control and gait function in chronic stroke. Methods This was a single-arm pilot study with a convenience sample of 8 stroke survivors with chronic hemiparetic gait, trained and tested in a laboratory. Subjects trained in dorsiflexion–plantarflexion by playing video games with the robot during three 1-hour training sessions weekly, totaling 560 repetitions per session. Assessments included paretic ankle ranges of motion, strength, motor control, and overground gait function. Results Improved paretic ankle motor control was seen as increased target success, along with faster and smoother movements. Walking velocity also increased significantly, whereas durations of paretic single support increased and double support decreased. Conclusions Robotic feedback training improved paretic ankle motor control with improvements in floor walking. Increased walking speeds were comparable with reports from other task-oriented, locomotor training approaches used in stroke, suggesting that a focus on ankle motor control may provide a valuable adjunct to locomotor therapies. PMID:21115945
A novel adaptive, real-time algorithm to detect gait events from wearable sensors.
Chia Bejarano, Noelia; Ambrosini, Emilia; Pedrocchi, Alessandra; Ferrigno, Giancarlo; Monticone, Marco; Ferrante, Simona
2015-05-01
A real-time, adaptive algorithm based on two inertial and magnetic sensors placed on the shanks was developed for gait-event detection. For each leg, the algorithm detected the Initial Contact (IC), as the minimum of the flexion/extension angle, and the End Contact (EC) and the Mid-Swing (MS), as minimum and maximum of the angular velocity, respectively. The algorithm consisted of calibration, real-time detection, and step-by-step update. Data collected from 22 healthy subjects (21 to 85 years) walking at three self-selected speeds were used to validate the algorithm against the GaitRite system. Comparable levels of accuracy and significantly lower detection delays were achieved with respect to other published methods. The algorithm robustness was tested on ten healthy subjects performing sudden speed changes and on ten stroke subjects (43 to 89 years). For healthy subjects, F1-scores of 1 and mean detection delays lower than 14 ms were obtained. For stroke subjects, F1-scores of 0.998 and 0.944 were obtained for IC and EC, respectively, with mean detection delays always below 31 ms. The algorithm accurately detected gait events in real time from a heterogeneous dataset of gait patterns and paves the way for the design of closed-loop controllers for customized gait trainings and/or assistive devices.
Begon, Mickaël; Leardini, Alberto; Belvedere, Claudio; Farahpour, Nader; Allard, Paul
2015-10-01
While sagittal trunk inclinations alter upper body biomechanics, little is known about the extent of frontal trunk bending on upper body and pelvis kinematics in adults during gait and its relation to sagittal trunk inclinations. The objective was to determine the effect of the mean lateral trunk attitude on upper body and pelvis three-dimensional kinematics during gait in asymptomatic subjects. Three gait cycles were collected in 30 subjects using a motion analysis system (Vicon 612) and an established protocol. Sub-groups were formed based on the mean thorax lateral bending angle, bending side, and also sagittal tilt. These were compared based on 38 peak angles identified on pelvis, thorax and shoulder kinematics using MANOVAs. A main effect for bending side (p = 0.038) was found, especially for thorax peak angles. Statistics revealed also a significant interaction (p = 0.04993) between bending side and tilt for the thorax sagittal inclination during body-weight transfer. These results reinforce the existence of different gait patterns, which correlate upper body and pelvis motion measures. The results also suggest that frontal and sagittal trunk attitude should be considered carefully when treating a patient with impaired gait. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.
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.
Shoe-Insole Technology for Injury Prevention in Walking
Nagano, Hanatsu
2018-01-01
Impaired walking increases injury risk during locomotion, including falls-related acute injuries and overuse damage to lower limb joints. Gait impairments seriously restrict voluntary, habitual engagement in injury prevention activities, such as recreational walking and exercise. There is, therefore, an urgent need for technology-based interventions for gait disorders that are cost effective, willingly taken-up, and provide immediate positive effects on walking. Gait control using shoe-insoles has potential as an effective population-based intervention, and new sensor technologies will enhance the effectiveness of these devices. Shoe-insole modifications include: (i) ankle joint support for falls prevention; (ii) shock absorption by utilising lower-resilience materials at the heel; (iii) improving reaction speed by stimulating cutaneous receptors; and (iv) preserving dynamic balance via foot centre of pressure control. Using sensor technology, such as in-shoe pressure measurement and motion capture systems, gait can be precisely monitored, allowing us to visualise how shoe-insoles change walking patterns. In addition, in-shoe systems, such as pressure monitoring and inertial sensors, can be incorporated into the insole to monitor gait in real-time. Inertial sensors coupled with in-shoe foot pressure sensors and global positioning systems (GPS) could be used to monitor spatiotemporal parameters in real-time. Real-time, online data management will enable ‘big-data’ applications to everyday gait control characteristics. PMID:29738486
del-Ama, Antonio J.; Gil-Agudo, Ángel; 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. PMID:24860478
Mollaei, Nafiseh; Bicho, Estela; Sousa, Nuno; Gago, Miguel Fernandes
2017-01-01
Imbalance and tripping over obstacles as a result of altered gait in older adults, especially in patients with Parkinson’s disease (PD), are one of the most common causes of falls. During obstacle crossing, patients with PD modify their behavior in order to decrease the mechanical demands and enhance dynamic stability. Various descriptions of dynamic traits of gait that have been collected over longer periods, probably better synthesize the underlying structure and pattern of fluctuations in gait and can be more sensitive markers of aging or early neurological dysfunction and increased risk of falls. This confirmation challenges the clinimetric of different protocols and paradigms used for gait analysis up till now, in particular when analyzing obstacle crossing. The authors here present a critical review of current knowledge concerning the interplay between the cognition and gait in aging and PD, emphasizing the differences in gait behavior and adaptability while walking over different and challenging obstacle paradigms, and the implications of obstacle negotiation as a predictor of falls. Some evidence concerning the effectiveness of future rehabilitation protocols on reviving obstacle crossing behavior by trial and error relearning, taking advantage of dual-task paradigms, physical exercise, and virtual reality have been put forward in this article. PMID:29158667
[Walking with canes and forearm-crutches (author's transl)].
Bergmann, G; Kölbel, R; Rauschenbach, N; Rohlmann, A
1978-02-01
Partial weight bearing is frequently prescribed but cannot be controlled adequately. In a previous paper the change of forces at the hip joint as effected by a one sided cane was determined by instrumentation of the cane and a mechanical analysis of gait on a walkway. In the present study we looked at the conditions for control of partial weightbearing when two forearm crutches are used. Instrumented crutches and a forceplate were used. In walking with two forearm crutches the total of the ground reaction forces and the force pattern differ from those in free walking. The total of two crutch forces plus the force at the leg with partial weightbearing exceeds that caused by body weight alone. This is due to mass accelerations in a changed gait pattern. When the maximal leg force is reduced from 100% body weight to zero, the additional dynamic forces exceed those caused by body weight alone by 4%-19%. Only 2% of the additional dynamic forces act on the controlateral crutch while the rest is transmitted through the ipsilateral crutch. The crutch force pattern on the ipsilateral side depends more on individual gait characteristics than does that on the controlateral side. Load reduction is more pronounced in the late stages of the stand phase than in the early ones.
Older adults adopted more cautious gait patterns when walking in socks than barefoot.
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.
Does the anthropometric model influence whole-body center of mass calculations in gait?
Catena, Robert D; Chen, Szu-Hua; Chou, Li-Shan
2017-07-05
Examining whole-body center of mass (COM) motion is one of method being used to quantify dynamic balance and energy during gait. One common method for estimating the COM position is to apply an anthropometric model to a marker set and calculate the weighted sum from known segmental COM positions. Several anthropometric models are available to perform such a calculation. However, to date there has been no study of how the anthropometric model affects whole-body COM calculations during gait. This information is pertinent to researchers because the choice of anthropometric model may influence gait research findings and currently the trend is to consistently use a single model. In this study we analyzed a single stride of gait data from 103 young adult participants. We compared the whole-body COM motion calculated from 4 different anthropometric models (Plagenhoef et al., 1983; Winter, 1990; de Leva, 1996; Pavol et al., 2002). We found that anterior-posterior motion calculations are relatively unaffected by the anthropometric model. However, medial-lateral and vertical motions are significantly affected by the use of different anthropometric models. Our findings suggest that the researcher carefully choose an anthropometric model to fit their study populations when interested in medial-lateral or vertical motions of the COM. Our data can provide researchers a priori information on the model determination depending on the particular variable and how conservative they may want to be with COM comparisons between groups. Copyright © 2017 Elsevier Ltd. All rights reserved.
Daryabor, Alieh; Arazpour, Mokhtar; Samadian, Mohammad; Veiskarami, Masoumeh; Ahmadi Bani, Monireh
2017-05-01
Adolescent idiopathic scoliosis (AIS) is a progressive growth disease that affects spinal anatomy, mobility, and left-right trunk symmetry. As a consequence, AIS can modify human gait. Spinal orthoses are a commonly used conservative method for the treatment of AIS. This review evaluated the AIS spinal orthosis literature that involved gait and energy consumption evaluations. Literature review. According to the population intervention comparison outcome measure methods and based on selected keywords, 10 studies met the inclusion criteria. People with AIS who wore a spinal orthosis, compared with able-bodied participants, walked slower with decreased hip and pelvic movements, decreased hip mediolateral forces, ground reaction force asymmetry, and excessive energy cost. Pelvis and hip frontal plane motion decreased when wearing an orthosis. Hip and pelvis movement symmetry improved when using an orthosis. Ankle and foot kinematics did not change with orthotic intervention. People with AIS continued to have excessive energy expenditure with an orthosis. Spinal orthoses may be considered for improving the walking style, although energy cost does not decline following the orthotic intervention. Implications for Rehabilitations Problems related to scoliosis include reduced quality of life, disability, pain, postural alterations, sensory perturbations, standing instability and gait modifications. Wearing corrective spinal orthoses in AIS subjects produce a reduction in walking speed and cadence, increase in stride length and reduction of gait load asymmetry compared to without brace condition. Spinal orthoses do not decline excessive energy expenditure to walk versus without it.
2014-01-01
Background Locomotion involves an integration of vision, proprioception, and vestibular information. The parieto-insular vestibular cortex is known to affect the supra-spinal rhythm generators, and the vestibular system regulates anti-gravity muscle tone of the lower leg in the same side to maintain an upright posture through the extra-pyramidal track. To demonstrate the relationship between locomotion and vestibular function, we evaluated the differences in gait patterns between vestibular neuritis (VN) patients and normal subjects using a gyroscope sensor and long-way walking protocol. Methods Gyroscope sensors were attached to both shanks of healthy controls (n=10) and age-matched VN patients (n = 10). We then asked the participants to walk 88.8 m along a corridor. Through the summation of gait cycle data, we measured gait frequency (Hz), normalized angular velocity (NAV) of each axis for legs, maximum and minimum NAV, up-slope and down-slope of NAV in swing phase, stride-swing-stance time (s), and stance to stride ratio (%). Results The most dominant walking frequency in the VN group was not different compared to normal control. The NAVs of z-axis (pitch motion) were significantly larger than the others (x-, y-axis) and the values in VN patients tended to decrease in both legs and the difference of NAV between both group was significant in the ipsi-lesion side in the VN group only (p=0.03). Additionally, the gait velocity of these individuals was decreased relatively to controls (1.11 ± 0.120 and 0.84 ± 0.061 m/s in control and VN group respectively, p<0.01), which seems to be related to the significantly increased stance and stride time of the ipsi-lesion side. Moreover, in the VN group, the maximum NAV of the lesion side was less, and the minimum one was higher than control group. Furthermore, the down-slope and up-slope of NAV decreased on the impaired side. Conclusion The walking pattern of VN patients was highly phase-dependent, and NAV of pitch motion was significantly decreased in the ipsi-lesion side. The change of gait rhythm, stance and stride time, and maximum/minimum NAV of the ipsi-lesion side were characteristics of individuals with VN. PMID:24725764
Kim, Soo Chan; Kim, Joo Yeon; Lee, Hwan Nyeong; Lee, Hwan Ho; Kwon, Jae Hwan; Kim, Nam Beom; Kim, Mi Joo; Hwang, Jong Hyun; Han, Gyu Cheol
2014-04-11
Locomotion involves an integration of vision, proprioception, and vestibular information. The parieto-insular vestibular cortex is known to affect the supra-spinal rhythm generators, and the vestibular system regulates anti-gravity muscle tone of the lower leg in the same side to maintain an upright posture through the extra-pyramidal track. To demonstrate the relationship between locomotion and vestibular function, we evaluated the differences in gait patterns between vestibular neuritis (VN) patients and normal subjects using a gyroscope sensor and long-way walking protocol. Gyroscope sensors were attached to both shanks of healthy controls (n=10) and age-matched VN patients (n = 10). We then asked the participants to walk 88.8 m along a corridor. Through the summation of gait cycle data, we measured gait frequency (Hz), normalized angular velocity (NAV) of each axis for legs, maximum and minimum NAV, up-slope and down-slope of NAV in swing phase, stride-swing-stance time (s), and stance to stride ratio (%). The most dominant walking frequency in the VN group was not different compared to normal control. The NAVs of z-axis (pitch motion) were significantly larger than the others (x-, y-axis) and the values in VN patients tended to decrease in both legs and the difference of NAV between both group was significant in the ipsi-lesion side in the VN group only (p=0.03). Additionally, the gait velocity of these individuals was decreased relatively to controls (1.11 ± 0.120 and 0.84 ± 0.061 m/s in control and VN group respectively, p<0.01), which seems to be related to the significantly increased stance and stride time of the ipsi-lesion side. Moreover, in the VN group, the maximum NAV of the lesion side was less, and the minimum one was higher than control group. Furthermore, the down-slope and up-slope of NAV decreased on the impaired side. The walking pattern of VN patients was highly phase-dependent, and NAV of pitch motion was significantly decreased in the ipsi-lesion side. The change of gait rhythm, stance and stride time, and maximum/minimum NAV of the ipsi-lesion side were characteristics of individuals with VN.
Yarnitzky, G; Yizhar, Z; Gefen, A
2006-01-01
No technology is presently available to provide real-time information on internal deformations and stresses in plantar soft tissues of individuals during evaluation of the gait pattern. Because internal deformations and stresses in the plantar pad are critical factors in foot injuries such as diabetic foot ulceration, this severely limits evaluation of patients. To allow such real-time subject-specific analysis, we developed a hierarchal modeling system which integrates a two-dimensional gross structural model of the foot (high-order model) with local finite element (FE) models of the plantar tissue padding the calcaneus and medial metatarsal heads (low-order models). The high-order whole-foot model provides real-time analytical evaluations of the time-dependent plantar fascia tensile forces during the stance phase. These force evaluations are transferred, together with foot-shoe local reaction forces, also measured in real time (under the calcaneus, medial metatarsals and hallux), to the low-order FE models of the plantar pad, where they serve as boundary conditions for analyses of local deformations and stresses in the plantar pad. After careful verification of our custom-made FE solver and of our foot model system with respect to previous literature and against experimental results from a synthetic foot phantom, we conducted human studies in which plantar tissue loading was evaluated in real time during treadmill gait in healthy individuals (N = 4). We concluded that internal deformations and stresses in the plantar pad during gait cannot be predicted from merely measuring the foot-shoe force reactions. Internal loading of the plantar pad is constituted by a complex interaction between the anatomical structure and mechanical behavior of the foot skeleton and soft tissues, the body characteristics, the gait pattern and footwear. Real-time FE monitoring of internal deformations and stresses in the plantar pad is therefore required to identify elevated deformation/stress exposures toward utilizing it in gait laboratories to protect feet that are susceptible to injury.
Maurer, Christian; Federolf, Peter; von Tscharner, Vinzenz; Stirling, Lisa; Nigg, Benno M
2012-05-01
Changes in gait kinematics have often been analyzed using pattern recognition methods such as principal component analysis (PCA). It is usually just the first few principal components that are analyzed, because they describe the main variability within a dataset and thus represent the main movement patterns. However, while subtle changes in gait pattern (for instance, due to different footwear) may not change main movement patterns, they may affect movements represented by higher principal components. This study was designed to test two hypotheses: (1) speed and gender differences can be observed in the first principal components, and (2) small interventions such as changing footwear change the gait characteristics of higher principal components. Kinematic changes due to different running conditions (speed - 3.1m/s and 4.9 m/s, gender, and footwear - control shoe and adidas MicroBounce shoe) were investigated by applying PCA and support vector machine (SVM) to a full-body reflective marker setup. Differences in speed changed the basic movement pattern, as was reflected by a change in the time-dependent coefficient derived from the first principal. Gender was differentiated by using the time-dependent coefficient derived from intermediate principal components. (Intermediate principal components are characterized by limb rotations of the thigh and shank.) Different shoe conditions were identified in higher principal components. This study showed that different interventions can be analyzed using a full-body kinematic approach. Within the well-defined vector space spanned by the data of all subjects, higher principal components should also be considered because these components show the differences that result from small interventions such as footwear changes. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.
Invariant hip moment pattern while walking with a robotic hip exoskeleton.
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.
Meyer, Andrew J; D'Lima, Darryl D; Besier, Thor F; Lloyd, David G; Colwell, Clifford W; Fregly, Benjamin J
2013-06-01
Mechanical loading is believed to be a critical factor in the development and treatment of knee osteoarthritis. However, the contact forces to which the knee articular surfaces are subjected during daily activities cannot be measured clinically. Thus, the ability to predict internal knee contact forces accurately using external measures (i.e., external knee loads and muscle electromyographic [EMG] signals) would be clinically valuable. We quantified how well external knee load and EMG measures predict internal knee contact forces during gait. A single subject with a force-measuring tibial prosthesis and post-operative valgus alignment performed four gait patterns (normal, medial thrust, walking pole, and trunk sway) to induce a wide range of external and internal knee joint loads. Linear regression analyses were performed to assess how much of the variability in internal contact forces was accounted for by variability in the external measures. Though the different gait patterns successfully induced significant changes in the external and internal quantities, changes in external measures were generally weak indicators of changes in total, medial, and lateral contact force. Our results suggest that when total contact force may be changing, caution should be exercised when inferring changes in knee contact forces based on observed changes in external knee load and EMG measures. Advances in musculoskeletal modeling methods may be needed for accurate estimation of in vivo knee contact forces. Copyright © 2012 Orthopaedic Research Society.
Velayutham, Selva Ganapathy; Chandra, Sadanandavalli Retnaswami; Bharath, Srikala; Shankar, Ravi Girikamatha
2017-01-01
Introduction: Alzhiemers disease and Frontotemporal dementia are common neurodegenerative dementias with a wide prevalence. Falls are a common cause of morbidity in these patients. Identifying subclinical involvement of these parameters might serve as a tool in differential analysis of these distinct parameters involved in these conditions and also help in planning preventive strategies to prevent falls. Patients and Methods: Eight patients in age and gender matched patients in each group were compared with normal controls. Standardizes methods of gait and balance aseesment were done in all persons. Results: Results revealed subclinical involvement of gait and balancesin all groups specially during divided attention. The parameters were significantly more affected in patients. Patients with AD and FTD had involement of over all ambulation index balance more affected in AD patients FTD patients showed step cycle, stride length abnormalities. Discussion: There is balance and gait involvement in normal ageing as well as patients with AD and FTD. The pattern of involvement in AD correlates with WHERE pathway involvement and FTD with frontal subcortical circuits involvement. Conclusion: Identification the differential patterns of involvement in subclinical stage might help to differentiate normal ageing and the different types of cortical dementias. This could serve as an additional biomarker and also assist in initiating appropriate training methods to prevent future falls. PMID:28515555
Rossi, Stefano; Colazza, Alessandra; Petrarca, Maurizio; Castelli, Enrico; Cappa, Paolo; Krebs, Hermano Igo
2013-01-01
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. PMID:24023822
Papagiannis, Georgios I; Roumpelakis, Ilias M; Triantafyllou, Athanasios I; Makris, Ioannis N; Babis, George C
2016-08-01
Total knee arthroplasties (TKAs) using well-designed, fixed bearing prostheses, such as medial pivot (MP), have produced good long-term results. Rotating-platform, posterior-stabilized (RP-PS) mobile bearing implants were designed to decrease polyethylene wear. Sagittal and coronal plane TKA biomechanics are well examined and correlated to polyethylene wear. However, limited research findings describe this relationship in transverse plane. We assumed that although axial plane biomechanics might not be the most destructive parameters on polyethylene wear, it is important to clarify their role because both joint kinematics and kinetics in all 3 planes are important input parameters for TKA wear testing (International Organization for Standardization 14243-1 and 14343-3). Our hypothesis was that transverse plane overall range of motion (ROM) and/or peak moment show differences that reflect on wear advantages when compared RP-PS implants to MP designs. Two groups (MPs = 24 and RP-PSs = 22 subjects) were examined by using 3D gait analysis. The variables were total internal-external rotation (IER) ROM and peak IER moments. No statistically significant difference was demonstrated between the 2 groups in kinetics (P = .389) or kinematics (P = .275). In the present study, no wear advantages were found between 2 TKAs. Both designs showed identical kinetics at the transverse plane in level-ground walking. Kinematic analysis could not illustrate any statistically significant difference in terms of overall IER ROM. Nevertheless, kinematic gait pattern differences observed possibly reflect different patterns of joint surface motion or abnormal gait patterns. Thus, wear testing with various input waveforms combined with functional data analysis will be necessary to identify the actual effects of gait variability on polyethylene wear. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
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.
Husa-Russell, Johanna; Ukelo, Thomas; List, Renate; Lorenzetti, Silvio; Wolf, Peter
2011-04-01
Before making interpretations on the effects of interventions or on the features of pathological gait patterns during stair ambulation, the day-to-day consistency of the investigated variables must be established. In this article, the day-to-day consistency was determined for kinematic variables during barefoot stair ambulation. Ten healthy athletes performed two gait analysis sessions, at least one week apart, utilizing a marker set of 47 skin markers, and a functional joint center/axes determination. Being found on limits of agreement and mean differences between the repeated stair ambulation sessions, totally 43 ranges of motions were examined at the hip, knee, ankle, and midfoot joints. The day-to-day consistency was generally in the magnitude of three degrees, irrespective of test condition, investigated joint, or regarded cardinal body plane. The reported values of the day-to-day consistency provide guidelines to distinguish between pathological and healthy gait patterns, and thresholds to determine minimal effects of interventions during stair ambulation. Copyright © 2011 Elsevier B.V. All rights reserved.
Spitz, Jonathan; Evstrachin, Alexandrina; Zacksenhouse, Miriam
2015-08-20
In recent years there has been a growing interest in the field of dynamic walking and bio-inspired robots. However, while walking and running on a flat surface have been studied extensively, walking dynamically over terrains with varying slope remains a challenge. Previously we developed an open loop controller based on a central pattern generator (CPG). The controller applied predefined torque patterns to a compass-gait biped, and achieved stable gaits over a limited range of slopes. In this work, this range is greatly extended by applying a once per cycle feedback to the CPG controller. The terrain's slope is measured and used to modify both the CPG frequency and the torque amplitude once per step. A multi-objective optimization algorithm was used to tune the controller parameters for a simulated CB model. The resulting controller successfully traverses terrains with slopes ranging from +7° to -8°, comparable to most slopes found in human constructed environments. Gait stability was verified by computing the linearized Poincaré Map both numerically and analytically.
The contribution of a central pattern generator in a reflex-based neuromuscular model
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
Influence of gait speed on stability: recovery from anterior slips and compensatory stepping.
Bhatt, T; Wening, J D; Pai, Y-C
2005-02-01
Falls precipitated by slipping are a major health concern, with the majority of all slip-related falls occurring during gait. Recent evidence shows that a faster and/or more anteriorly positioned center of mass (COM) is more stable against backward balance loss, and that compensatory stepping is the key to recovering stability upon balance loss. The purposes of this paper were to determine whether walking speed affected gait stability for backward balance loss at slip onset and touchdown of compensatory stepping, and whether compensatory stepping response resembled the regular gait pattern. Forty-seven young subjects were slipped unexpectedly either at a self-selected fast, natural or slow speed. Speed-related differences in stability at slip onset and touchdown of the subsequent compensatory step were analyzed using the COM position-velocity state. The results indicate that gait speed highly correlated with stability against backward balance loss at slip onset. The low COM velocity of the slow group was not sufficiently compensated for by a more anteriorly positioned COM associated with a shorter step length at slip onset. At touchdown of the compensatory step, the speed-related differences in stability diminished, due to the continued advantage of anterior COM positioning from a short compensatory step retained by the slow group, coupled with an increase in COM velocity. Compensatory step length and relative COM position altered as a function of gait speed, indicating the motor program for gait regulation may play a role in modulating the compensatory step.
Henriksen, Marius; Klokker, Louise; Bartholdy, Cecilie; Schjoedt-Jorgensen, Tanja; Bandak, Elisabeth; Bliddal, Henning
2016-01-01
To assess the effects of a functional and individualised exercise programme on gait biomechanics during walking in people with knee OA. Sixty participants were randomised to 12 weeks of facility-based functional and individualised neuromuscular exercise therapy (ET), 3 sessions per week supervised by trained physical therapists, or a no attention control group (CG). Three-dimensional gait analyses were used, from which a comprehensive list of conventional gait variables were extracted (totally 52 kinematic, kinetic and spatiotemporal variables). According to the protocol, the analyses were based on the 'Per-Protocol' population (defined as participants following the protocol with complete and valid gait analyses). Analysis of covariance adjusting for the level at baseline was used to determine differences between groups (95% CIs) in the changes from baseline at follow-up. The per-protocol population included 46 participants (24 ET/22 CG). There were no group differences in the analysed gait variables, except for a significant group difference in the second peak knee flexor moment and second peak vertical ground reaction force. While plausible we have limited confidence in the findings due to multiple statistical tests and lack of biomechanical logics. Therefore we conclude that a 12-week supervised individualised neuromuscular exercise programme has no effects on gait biomechanics. Future studies should focus on exercise programmes specifically designed to alter gait patterns, or include other measures of mobility, such as walking on stairs or inclined surfaces. ClinicalTrials.gov: NCT01545258.
Monticone, Marco; Ambrosini, Emilia; Fiorentini, Roberta; Rocca, Barbara; Liquori, Valentina; Pedrocchi, Alessandra; Ferrante, Simona
2014-09-01
To evaluate the reliability and minimum detectable change (MDC) of spatial-temporal gait parameters in subjects with multiple sclerosis (MS) during dual tasking. This cross-sectional study involved 25 healthy subjects (mean age 49.9 ± 15.8 years) and 25 people with MS (mean age 49.2 ± 11.5 years). Gait under motor-cognitive and motor-motor dual tasking conditions was evaluated in two sessions separated by a one-day interval using the GAITRite Walkway System. Test-retest reliability was assessed using intraclass correlation coefficients (ICCs), standard errors of measurement (SEM), and coefficients of variation (CV). MDC scores were computed for the velocity, cadence, step and stride length, step and stride time, double support time, the % of gait cycle for single support and stance phase, and base of support. All of the gait parameters reported good to excellent ICCs under both conditions, with healthy subject values of >0.69 and MS subject values of >0.84. SEM values were always below 18% for both groups of subjects. The gait patterns of the people with MS were slightly more variable than those of the normal controls (CVs: 5.88-41.53% vs 2.84-30.48%). The assessment of quantitative gait parameters in healthy subjects and people with MS is highly reliable under both of the investigated dual tasking conditions. Copyright © 2014 Elsevier B.V. All rights reserved.
Lopez, William Omar Contreras; Higuera, Carlos Andres Escalante; Fonoff, Erich Talamoni; Souza, Carolina de Oliveira; Albicker, Ulrich; Martinez, Jairo Alberto Espinoza
2014-10-01
Evidence supports the use of rhythmic external auditory signals to improve gait in PD patients (Arias & Cudeiro, 2008; Kenyon & Thaut, 2000; McIntosh, Rice & Thaut, 1994; McIntosh et al., 1997; Morris, Iansek, & Matyas, 1994; Thaut, McIntosh, & Rice, 1997; Suteerawattananon, Morris, Etnyre, Jankovic, & Protas , 2004; Willems, Nieuwboer, Chavert, & Desloovere, 2006). However, few prototypes are available for daily use, and to our knowledge, none utilize a smartphone application allowing individualized sounds and cadence. Therefore, we analyzed the effects on gait of Listenmee®, an intelligent glasses system with a portable auditory device, and present its smartphone application, the Listenmee app®, offering over 100 different sounds and an adjustable metronome to individualize the cueing rate as well as its smartwatch with accelerometer to detect magnitude and direction of the proper acceleration, track calorie count, sleep patterns, steps count and daily distances. The present study included patients with idiopathic PD presented gait disturbances including freezing. Auditory rhythmic cues were delivered through Listenmee®. Performance was analyzed in a motion and gait analysis laboratory. The results revealed significant improvements in gait performance over three major dependent variables: walking speed in 38.1%, cadence in 28.1% and stride length in 44.5%. Our findings suggest that auditory cueing through Listenmee® may significantly enhance gait performance. Further studies are needed to elucidate the potential role and maximize the benefits of these portable devices. Copyright © 2014 Elsevier B.V. All rights reserved.
A Neuro-Musculo-Skeletal Model for Insects With Data-driven Optimization.
Guo, Shihui; Lin, Juncong; Wöhrl, Toni; Liao, Minghong
2018-02-01
Simulating the locomotion of insects is beneficial to many areas such as experimental biology, computer animation and robotics. This work proposes a neuro-musculo-skeletal model, which integrates the biological inspirations from real insects and reproduces the gait pattern on virtual insects. The neural system is a network of spiking neurons, whose spiking patterns are controlled by the input currents. The spiking pattern provides a uniform representation of sensory information, high-level commands and control strategy. The muscle models are designed following the characteristic Hill-type muscle with customized force-length and force-velocity relationships. The model parameters, including both the neural and muscular components, are optimized via an approach of evolutionary optimization, with the data captured from real insects. The results show that the simulated gait pattern, including joint trajectories, matches the experimental data collected from real ants walking in the free mode. The simulated character is capable of moving at different directions and traversing uneven terrains.
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 < 0.005) and BF (PM < AM, p = 0.008) activity was observed in control participants. Conversely no circadian variation was seen in any muscles in the RLS patients. RLS patients had an increased TA and GL activity (RLS > 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.
Decker, Leslie M; Cignetti, Fabien; Hunt, Nathaniel; Potter, Jane F; Stergiou, Nicholas; Studenski, Stephanie A
2016-08-01
A U-shaped relationship between cognitive demand and gait control may exist in dual-task situations, reflecting opposing effects of external focus of attention and attentional resource competition. The purpose of the study was twofold: to examine whether gait control, as evaluated from step-to-step variability, is related to cognitive task difficulty in a U-shaped manner and to determine whether age modifies this relationship. Young and older adults walked on a treadmill without attentional requirement and while performing a dichotic listening task under three attention conditions: non-forced (NF), forced-right (FR), and forced-left (FL). The conditions increased in their attentional demand and requirement for inhibitory control. Gait control was evaluated by the variability of step parameters related to balance control (step width) and rhythmic stepping pattern (step length and step time). A U-shaped relationship was found for step width variability in both young and older adults and for step time variability in older adults only. Cognitive performance during dual tasking was maintained in both young and older adults. The U-shaped relationship, which presumably results from a trade-off between an external focus of attention and competition for attentional resources, implies that higher-level cognitive processes are involved in walking in young and older adults. Specifically, while these processes are initially involved only in the control of (lateral) balance during gait, they become necessary for the control of (fore-aft) rhythmic stepping pattern in older adults, suggesting that attentional resources turn out to be needed in all facets of walking with aging. Finally, despite the cognitive resources required by walking, both young and older adults spontaneously adopted a "posture second" strategy, prioritizing the cognitive task over the gait task.
Weakening iliopsoas muscle in healthy adults may induce stiff knee pattern.
Akalan, N Ekin; Kuchimov, Shavkat; Apti, Adnan; Temelli, Yener; Nene, Anand
2016-12-01
The goal of the present study was to investigate the relationship between iliopsoas muscle group weakness and related hip joint velocity reduction and stiff-knee gait (SKG) during walking in healthy individuals. A load of 5% of each individual's body weight was placed on non-dominant thigh of 15 neurologically intact, able-bodied participants (average age: 22.4 ± 0.81 years). For 33 min (135 s × 13 repetitions × 5 s rest), a passive stretch (PS) was applied with the load in place until hip flexor muscle strength dropped from 5/5 to 3+/5 according to manual muscle test. All participants underwent gait analysis before and after PS to compare sagittal plane hip, knee, and ankle kinematics and kinetics and temporo-spatial parameters. Paired t-test was used to compare pre- and post-stretch findings and Pearson correlation coefficient (r) was calculated to determine strength of correlation between SKG parameters and gait parameters of interest (p < 0.05). Reduced hip flexion velocity (mean: 21.5%; p = 0.005) was a contributor to SKG, decreasing peak knee flexion (PKF) (-20%; p = 0.0008), total knee range (-18.9%; p = 0.003), and range of knee flexion between toe-off and PKF (-26.7%; p = 0.001), and shortening duration between toe-off to PKF (-16.3%; p = 0.0005). These findings verify that any treatment protocol that slows hip flexion during gait by weakening iliopsoas muscle may have great potential to produce SKG pattern combined with reduced gait velocity. Copyright © 2016 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.
Tegotae-based decentralised control scheme for autonomous gait transition of snake-like robots.
Kano, Takeshi; Yoshizawa, Ryo; Ishiguro, Akio
2017-08-04
Snakes change their locomotion patterns in response to the environment. This ability is a motivation for developing snake-like robots with highly adaptive functionality. In this study, a decentralised control scheme of snake-like robots that exhibited autonomous gait transition (i.e. the transition between concertina locomotion in narrow aisles and scaffold-based locomotion on unstructured terrains) was developed. Additionally, the control scheme was validated via simulations. A key insight revealed is that these locomotion patterns were not preprogrammed but emerged by exploiting Tegotae, a concept that describes the extent to which a perceived reaction matches a generated action. Unlike local reflexive mechanisms proposed previously, the Tegotae-based feedback mechanism enabled the robot to 'selectively' exploit environments beneficial for propulsion, and generated reasonable locomotion patterns. It is expected that the results of this study can form the basis to design robots that can work under unpredictable and unstructured environments.
Convergent evolution in locomotory patterns of flying and swimming animals.
Gleiss, Adrian C; Jorgensen, Salvador J; Liebsch, Nikolai; Sala, Juan E; Norman, Brad; Hays, Graeme C; Quintana, Flavio; Grundy, Edward; Campagna, Claudio; Trites, Andrew W; Block, Barbara A; Wilson, Rory P
2011-06-14
Locomotion is one of the major energetic costs faced by animals and various strategies have evolved to reduce its cost. Birds use interspersed periods of flapping and gliding to reduce the mechanical requirements of level flight while undergoing cyclical changes in flight altitude, known as undulating flight. Here we equipped free-ranging marine vertebrates with accelerometers and demonstrate that gait patterns resembling undulating flight occur in four marine vertebrate species comprising sharks and pinnipeds. Both sharks and pinnipeds display intermittent gliding interspersed with powered locomotion. We suggest, that the convergent use of similar gait patterns by distinct groups of animals points to universal physical and physiological principles that operate beyond taxonomic limits and shape common solutions to increase energetic efficiency. Energetically expensive large-scale migrations performed by many vertebrates provide common selection pressure for efficient locomotion, with potential for the convergence of locomotory strategies by a wide variety of species.
Quadruped robots' modular trajectories: Stability issues
NASA Astrophysics Data System (ADS)
Pinto, Carla M. A.
2012-09-01
Pinto, Santos, Rocha and Matos [13, 12] study a CPG model for the generation of modular trajectories of quadruped robots. They consider that each movement is composed of two types of primitives: rhythmic and discrete. The rhythmic primitive models the periodic patterns and the discrete primitive is inserted as a perturbation of those patterns. In this paper we begin to tackle numerically the problem of the stability of that mathematical model. We observe that if the discrete part is inserted in all limbs, with equal values, and as an offset of the rhythmic part, the obtained gait is stable and has the same spatial and spatio-temporal symmetry groups as the purely rhythmic gait, differing only on the value of the offset.
2011-01-01
Background The computer-aided identification of specific gait patterns is an important issue in the assessment of Parkinson's disease (PD). In this study, a computer vision-based gait analysis approach is developed to assist the clinical assessments of PD with kernel-based principal component analysis (KPCA). Method Twelve PD patients and twelve healthy adults with no neurological history or motor disorders within the past six months were recruited and separated according to their "Non-PD", "Drug-On", and "Drug-Off" states. The participants were asked to wear light-colored clothing and perform three walking trials through a corridor decorated with a navy curtain at their natural pace. The participants' gait performance during the steady-state walking period was captured by a digital camera for gait analysis. The collected walking image frames were then transformed into binary silhouettes for noise reduction and compression. Using the developed KPCA-based method, the features within the binary silhouettes can be extracted to quantitatively determine the gait cycle time, stride length, walking velocity, and cadence. Results and Discussion The KPCA-based method uses a feature-extraction approach, which was verified to be more effective than traditional image area and principal component analysis (PCA) approaches in classifying "Non-PD" controls and "Drug-Off/On" PD patients. Encouragingly, this method has a high accuracy rate, 80.51%, for recognizing different gaits. Quantitative gait parameters are obtained, and the power spectrums of the patients' gaits are analyzed. We show that that the slow and irregular actions of PD patients during walking tend to transfer some of the power from the main lobe frequency to a lower frequency band. Our results indicate the feasibility of using gait performance to evaluate the motor function of patients with PD. Conclusion This KPCA-based method requires only a digital camera and a decorated corridor setup. The ease of use and installation of the current method provides clinicians and researchers a low cost solution to monitor the progression of and the treatment to PD. In summary, the proposed method provides an alternative to perform gait analysis for patients with PD. PMID:22074315
Froehle, Andrew W; Nahhas, Ramzi W; Sherwood, Richard J; Duren, Dana L
2013-05-01
Walking gait is generally held to reach maturity, including walking at adult-like velocities, by 7-8 years of age. Lower limb length, however, is a major determinant of gait, and continues to increase until 13-15 years of age. This study used a sample from the Fels Longitudinal Study (ages 8-30 years) to test the hypothesis that walking with adult-like velocity on immature lower limbs results in the retention of immature gait characteristics during late childhood and early adolescence. There was no relationship between walking velocity and age in this sample, whereas the lower limb continued to grow, reaching maturity at 13.2 years in females and 15.6 years in males. Piecewise linear mixed models regression analysis revealed significant age-related trends in normalized cadence, initial double support time, single support time, base of support, and normalized step length in both sexes. Each trend reached its own, variable-specific age at maturity, after which the gait variables' relationships with age reached plateaus and did not differ significantly from zero. Offsets in ages at maturity occurred among the gait variables, and between the gait variables and lower limb length. The sexes also differed in their patterns of maturation. Generally, however, immature walkers of both sexes took more frequent and relatively longer steps than did mature walkers. These results support the hypothesis that maturational changes in gait accompany ongoing lower limb growth, with implications for diagnosing, preventing, and treating movement-related disorders and injuries during late childhood and early adolescence. Copyright © 2012 Elsevier B.V. All rights reserved.
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.
Brozgol, Marina; Arbiv, Mira; Mirelman, Anat; Herman, Talia; Hausdorff, Jeffrey M; Vaisman, Nachum
2017-05-01
Osteoporosis is a systemic skeletal disease that is characterized by reduced bone mass, deterioration of bone tissue and skeletal fragility. The purpose of the current study was to determine whether asymmetrical femur bone mineral density (BMD) is associated with asymmetrical gait and standing. We compared measures of gait and standing asymmetry in subjects with (n=38) and without (n=11) significant left-right differences in BMD. Participants walked for 72m at their comfortable speed and stood quietly for 60s while outfitted with pressure-sensitive insoles. Based on the pressure measurements, indices of standing and gait asymmetry were determined. Gait Asymmetry (GA) indices of maximum ground reaction force (GRF) and stance time were significantly higher in the asymmetrical BMD group, compared to the symmetrical group (p<0.03). During quiet standing, maximal GRF was twice as high in those with BMD asymmetry, compared to those without, although this difference was not statistically significant (p=0.10). These preliminary findings indicate that femur BMD asymmetry and gait asymmetry are interrelated in otherwise healthy adults. Nutrition, metabolism and lifestyle are known contributors to BMD; typically, they affect bone health symmetrically. We suggest, therefore, that the BMD asymmetry may be due to previous changes in the loading pattern during walking that might have led to asymmetric bone deterioration. Future larger scale and prospective studies are needed to identify the mechanisms underlying the relationship between standing, gait and BMD and to explore whether gait training and exercises that target gait symmetry might help to reduce BMD asymmetry. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
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.
The Importance of Mid-to-Late-Life Body Mass Index Trajectories on Late-Life Gait Speed.
Windham, B Gwen; Griswold, Michael E; Wang, Wanmei; Kucharska-Newton, Anna; Demerath, Ellen W; Gabriel, Kelley Pettee; Pompeii, Lisa A; Butler, Kenneth; Wagenknecht, Lynne; Kritchevsky, Stephen; Mosley, Thomas H
2017-08-01
Prior studies suggest being overweight may be protective against poor functional outcomes in older adults. Body mass index (BMI, kg/m2) was measured over 25 years across five visits (1987-2011) among Atherosclerosis Risk in Communities Study participants (baseline Visit 1 n = 15,720, aged 45-64 years). Gait speed was measured at Visit 5 ("late-life", aged ≥65 years, n = 6,229). BMI trajectories were examined using clinical cutpoints and continuous mixed models to estimate effects of patterns of BMI change on gait speed, adjusting for demographics and comorbidities. Mid-life BMI (baseline visit; 55% women; 27% black) was associated with late-life gait speed 25 years later; gait speeds were 94.3, 89.6, and 82.1 cm/s for participants with baseline normal BMI (<25), overweight (25 ≤ BMI < 30), and obese (BMI ≥ 30) (p < .001). In longitudinal analyses, late-life gait speeds were 96.9, 88.8, and 81.3 cm/s for participants who maintained normal, overweight, and obese weight status, respectively, across 25 years (p < .01). Increasing BMI over 25 years was associated with poorer late-life gait speeds; a 1%/year BMI increase for a participant with a baseline BMI of 22.5 (final BMI 28.5) was associated with a 4.6-cm/s (95% confidence interval: -7.0, -1.8) slower late-life gait speed than a participant who maintained a baseline BMI of 22.5. Being overweight in older age was not protective of mobility function. Maintaining a normal BMI in mid- and late-life may help preserve late-life mobility. © The Author 2016. 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.
Czupryna, Krzysztof; Nowotny, Janusz
2012-01-01
Physiological human gait is characterized by tree-dimensional pelvis movements, which make that gait is smooth and does not require excessive energy expenditure. In children with cerebral palsy determinants of the pelvis may be affected, mainly due to pathological afferent synergisms. Therefore many specialists is looking for ways to improve this situation. The aim of this study was to verify whether the use of botulinium toxin or inhibitive casts affects the kinematic parameters of the pelvis during the gait of children with hemiparetic form of cerebral palsy. The study involved 34 hemiparetic children with cerebral palsy aged 7-14 years who reached the capacity of walking. All were improving by neurodevelop-mental treatment according to NDT-Bobath method. Two groups were created. In the first group inhibiting casting was used in 16 children. In the second group botulinium toxin was injected in 18 children. Gait analysis was performed before and after using those type of treatment. Ultrasonic CMS-HS system (Zebris) was used for three dimensional gait analysis. Despite of the characteristic for hemiplegic gait pattern asymmetry, various ab-normalities of pelvis kinematic parameters were observed. Gait symmetry was improved aafter the treatment. Using inhibiting casts also improved kinematic parameters of the pelvis, especially in those children who are found deficit of decreasing and rotation of the pelvis. 1) The use of Btx-A or inhibitive casts results in improving temporal- spatial parameters of gait of cerebral palsied children with hemiparesis. 2) The improvement of kinematic pelvis parameters are obtained through the use of inhibitive casts, while the use of Btx-A does not have a significant impact on them.
Czupryna, Krzysztof; Nowotny, Janusz
2012-01-01
Physiological human gait is characterized by changes of foot and knee angle that make the gait efficient and not require excessive energy expenditure. In cerebral palsied children, the foot-knee relationship is disturbed by pathological synergies. Therefore, ways to improve this situation are sought. The aim of the study was to verify whether and how well the use of botulinum toxin or inhibitive casts alters the behaviour of the foot-knee complex in cerebral palsy gait. The study involved 34 hemiparetic children with cerebral palsy aged 7-14 years who were able to walk unassisted. Neurodevelopmental treatment according to the NDT-Bobath method was given to all the children. Two groups were formed. In the first group of 16 children, inhibitive castings were used. The second group of 18 children received Btx-A injections. Gait analysis was performed at baseline and one month after administering these additional treatments. The CMS-HS ultrasonic system (Zebris) was used for three dimensional gait analysis. Apart from the pattern asymmetry characteristic of a hemiplegic gait, various pronounced abnormalities of the foot-knee complex were observed. Following treatment, gait symmetry improved in both groups as did the position of the hemiparetic foot in the mid-support phase. In the inhibitive casting groups, similar improvements were also observed in the initial contact phase. In the knee, greater improvement in knee was noted in the Btx-A group. Btx-A injections or inhibitive casts improve gait parameters in cerebral palsied children. This improvement is individual and seen in different stages of the support phase, but of similar magnitude following the use of either treatment. Achieving simultaneous improvement in the knee and foot is difficult.
Carcreff, Lena; Paraschiv-Ionescu, Anisoara; De Coulon, Geraldo; Armand, Stéphane; Aminian, Kamiar
2018-01-01
Wearable inertial devices have recently been used to evaluate spatiotemporal parameters of gait in daily life situations. Given the heterogeneity of gait patterns in children with cerebral palsy (CP), the sensor placement and analysis algorithm may influence the validity of the results. This study aimed at comparing the spatiotemporal measurement performances of three wearable configurations defined by different sensor positioning on the lower limbs: (1) shanks and thighs, (2) shanks, and (3) feet. The three configurations were selected based on their potential to be used in daily life for children with CP and typically developing (TD) controls. For each configuration, dedicated gait analysis algorithms were used to detect gait events and compute spatiotemporal parameters. Fifteen children with CP and 11 TD controls were included. Accuracy, precision, and agreement of the three configurations were determined in comparison with an optoelectronic system as a reference. The three configurations were comparable for the evaluation of TD children and children with a low level of disability (CP-GMFCS I) whereas the shank-and-thigh-based configuration was more robust regarding children with a higher level of disability (CP-GMFCS II–III). PMID:29385700
Gait and energy consumption in adolescent idiopathic scoliosis: A literature review.
Daryabor, Aliyeh; Arazpour, Mokhtar; Sharifi, Guive; Bani, Monireh Ahmadi; Aboutorabi, Atefeh; Golchin, Navid
2017-04-01
Adolescent idiopathic scoliosis (AIS) is a progressive growth disease that affects spinal anatomy, mobility, and left-right trunk symmetry. The disease can modify human gait. We aimed to review articles describing the measurement of gait parameters and energy consumption in AIS during walking without any intervention. Literature review. The search strategy was based on the Population Intervention Comparison Outcome method and included all relevant articles published from 1996 to 2015. Articles were searched in MEDLINE via PubMed, Science Direct, Google Scholar, and ISI Web of Knowledge databases. We selected 33 studies investigating the effect of scoliosis deformity on gait parameters and energy expenditure during walking. Most of the studies concluded no significant differences in walking speed, cadence and step width in scoliosis patients and normal participants. However, patients showed decreased hip and pelvic motion, excessive energy cost of walking, stepping pattern asymmetry and ground reaction force asymmetry. We lack consistent evidence of the effect of scoliosis on temporal spatial and kinematic parameters in AIS patients as compared with normal people. However, further research is needed to assess the effect of scoliosis on gait and energy consumption. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Kawamoto, Hiroaki; Kandone, Hideki; Sakurai, Takeru; Ariyasu, Ryohei; Ueno, Yukiko; Eguchi, Kiyoshi; Sankai, Yoshiyuki
2014-01-01
Among several characteristics seen in gait of hemiplegic patients after stroke, symmetry is known to be an indicator of the degree of impairment of walking ability. This paper proposes a control method for a wearable type lower limb motion assist robot to realize spontaneous symmetric gait for these individuals. This control method stores the motion of the unaffected limb during swing 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. This method is implemented on the robot suit HAL (Hybrid Assistive Limbs). Clinical tests were conducted in order to assess the feasibility of the control method. Our case study involved participation of one chronic stroke patient who was not able to flex his right knee. As a result, the walking support for hemiplegic leg provided by the HAL improved the subject's gait symmetry. The feasibility study showed promising basis for the future clinical study.
Does external walking environment affect gait patterns?
Patterson, Matthew R; Whelan, Darragh; Reginatto, Brenda; Caprani, Niamh; Walsh, Lorcan; Smeaton, Alan F; Inomata, Akihiro; Caulfield, Brian
2014-01-01
The objective of this work is to develop an understanding of the relationship between mobility metrics obtained outside of the clinic or laboratory and the context of the external environment. Ten subjects walked with an inertial sensor on each shank and a wearable camera around their neck. They were taken on a thirty minute walk in which they mobilized over the following conditions; normal path, busy hallway, rough ground, blind folded and on a hill. Stride time, stride time variability, stance time and peak shank rotation rate during swing were calculated using previously published algorithms. Stride time was significantly different between several of the conditions. Technological advances mean that gait variables can now be captured as patients go about their daily lives. The results of this study show that the external environment has a significant impact on the quality of gait metrics. Thus, context of external walking environment is an important consideration when analyzing ambulatory gait metrics from the unsupervised home and community setting.
Damiano, Diane L.; Bulea, Thomas C.
2016-01-01
Individuals with cerebral palsy frequently exhibit crouch gait, a pathological walking pattern characterized by excessive knee flexion. Knowledge of the knee joint moment during crouch gait is necessary for the design and control of assistive devices used for treatment. Our goal was to 1) develop statistical models to estimate knee joint moment extrema and dynamic stiffness during crouch gait, and 2) use the models to estimate the instantaneous joint moment during weight-acceptance. We retrospectively computed knee moments from 10 children with crouch gait and used stepwise linear regression to develop statistical models describing the knee moment features. The models explained at least 90% of the response value variability: peak moment in early (99%) and late (90%) stance, and dynamic stiffness of weight-acceptance flexion (94%) and extension (98%). We estimated knee extensor moment profiles from the predicted dynamic stiffness and instantaneous knee angle. This approach captured the timing and shape of the computed moment (root-mean-squared error: 2.64 Nm); including the predicted early-stance peak moment as a correction factor improved model performance (root-mean-squared error: 1.37 Nm). Our strategy provides a practical, accurate method to estimate the knee moment during crouch gait, and could be used for real-time, adaptive control of robotic orthoses. PMID:27101612
Kloos, Anne D; Kegelmeyer, Deborah A; White, Susan E; Kostyk, Sandra K
2012-01-01
Gait and balance impairments lead to frequent falls and injuries in individuals with Huntington's disease (HD). Assistive devices (ADs) such as canes and walkers are often prescribed to prevent falls, but their efficacy is unknown. We systematically examined the effects of different types of ADs on quantitative gait measures during walking in a straight path and around obstacles. Spatial and temporal gait parameters were measured in 21 subjects with HD as they walked across a GAITRite walkway under 7 conditions (i.e., using no AD and 6 commonly prescribed ADs: a cane, a weighted cane, a standard walker, and a 2, 3 or 4 wheeled walker). Subjects also were timed and observed for number of stumbles and falls while walking around two obstacles in a figure-of-eight pattern. Gait measure variability (i.e., coefficient of variation), an indicator of fall risk, was consistently better when using the 4WW compared to other ADs. Subjects also walked the fastest and had the fewest number of stumbles and falls when using the 4WW in the figure-of-eight course. Subjects walked significantly slower using ADs compared to no AD both across the GAITRite and in the figure-of-eight. Measures reflecting gait stability and safety improved with the 4WW but were made worse by some other ADs.
White, Susan E.; Kostyk, Sandra K.
2012-01-01
Background Gait and balance impairments lead to frequent falls and injuries in individuals with Huntington's disease (HD). Assistive devices (ADs) such as canes and walkers are often prescribed to prevent falls, but their efficacy is unknown. We systematically examined the effects of different types of ADs on quantitative gait measures during walking in a straight path and around obstacles. Methods Spatial and temporal gait parameters were measured in 21 subjects with HD as they walked across a GAITRite walkway under 7 conditions (i.e., using no AD and 6 commonly prescribed ADs: a cane, a weighted cane, a standard walker, and a 2, 3 or 4 wheeled walker). Subjects also were timed and observed for number of stumbles and falls while walking around two obstacles in a figure-of-eight pattern. Results Gait measure variability (i.e., coefficient of variation), an indicator of fall risk, was consistently better when using the 4WW compared to other ADs. Subjects also walked the fastest and had the fewest number of stumbles and falls when using the 4WW in the figure-of-eight course. Subjects walked significantly slower using ADs compared to no AD both across the GAITRite and in the figure-of-eight. Measures reflecting gait stability and safety improved with the 4WW but were made worse by some other ADs. PMID:22363511
Zhao, Dong; Banks, Scott A; Mitchell, Kim H; D'Lima, Darryl D; Colwell, Clifford W; Fregly, Benjamin J
2007-06-01
The external knee adduction torque has been proposed as a surrogate measure for medial compartment load during gait. However, a direct link between these two quantities has not been demonstrated using in vivo measurement of medial compartment load. This study uses in vivo data collected from a single subject with an instrumented knee implant to evaluate this link. The subject performed five different overground gait motions (normal, fast, slow, wide, and toe-out) with simultaneous collection of instrumented implant, video motion, and ground reaction data. For each trial, the knee adduction torque was measured externally while the total axial force applied to the tibial insert was measured internally. Based on data collected from the same subject performing treadmill gait under fluoroscopic motion analysis, a regression equation was developed to calculate medial contact force from the implant load cell measurements. Correlation analyses were performed for the stance phase and entire gait cycle to quantify the relationship between the knee adduction torque and both the medial contact force and the medial to total contact force ratio. When the entire gait cycle was analyzed, R(2) for medial contact force was 0.77 when all gait trials were analyzed together and between 0.69 and 0.93 when each gait trial was analyzed separately (p < 0.001 in all cases). For medial to total force ratio, R(2) was 0.69 for all trials together and between 0.54 and 0.90 for each trial separately (p < 0.001 in all cases). When only the stance phase was analyzed, R(2) values were slightly lower. These results support the hypothesis that the knee adduction torque is highly correlated with medial compartment contact force and medial to total force ratio during gait. (c) 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Ravera, Emiliano Pablo; Catalfamo Formento, Paola Andrea; José Crespo, Marcos; Andrés Braidot, Ariel
2011-12-01
Cerebral Palsy represents the most common cause of physical disability in modern world and within the pediatrics orthopedics units. The gait analysis provides great contributions to the understanding of gait disorders in CP. Giving a more comprehensive treatment plan, including or excluding surgical procedures that can potentially decrease the number of surgical interventions in the life of these patients. Recommendations for orthopedic surgery may be based on a quantitative description of how to alter the properties probably muscle force generation, and how this affects the action of the muscle to determine how these muscles, impaired by disease or surgery, contributing to the movement of the segments of the limb during crouch gait. So the causes and appropriate treatment of gait abnormalities are difficult to determine because the movements generated by the muscular forces of these patients are not clearly understood. A correct determination of the etiology of abnormal patterns of the knee is the key to select the appropriate therapy, presenting a major challenge at present since there is no theoretical basis to determine the biomechanical causes of abnormal gait of these patients. The potential and necessity of using correct biomechanical models that consistently study the abnormalities becomes clear. Reinforcing and correcting a simple gait analysis and eliminating the unknowns when selecting the appropriate treatment is crucial in clinical settings. In this paper a computer muscle-skeletal model is proposed. The model represents a person's thigh simulating the six most representative muscles and joints of the hip and knee. In this way you can have a better understanding of gait abnormalities present in these patients. So the quality of these estimates of individual muscle dynamics facilitate better understanding of the biomechanics of gait pathologies helping to reach better diagnosis prior to surgery and rehabilitation treatments.
Wang, Xiao Hong; Lu, Gang; Hu, Xiang; Tsang, Kam Sze; Kwong, Wing Hang; Wu, Feng Xia; Meng, Hai Wei; Jiang, Shu; Liu, Shu Wei; Ng, Ho Keung; Poon, Wai Sang
2012-11-14
Gait deficits are important clinical symptoms of Parkinson's disease (PD). However, existing behavioral tests for the detection of motor impairments in rodents with systemic dopamine depletion only measure akinesia and dyskinesia, and data focusing on gait are scarce. We evaluated gait changes in the methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced C57BL/6 murine model of PD by using a computer-assisted CatWalk system. Correlations of gait parameters with tyrosine hydroxylase (TH) protein levels in the substantia nigra (SN) were also investigated. The gait readouts, including the walking duration, variation of walking speed, step cycle, duty cycle, stance, initial dual stance, terminal dual stance, three- and four-point supports, and the base of support between hind limbs was noted to increase significantly one week after MPTP injection. In contrast, values of the stride length, cadence, swing speed, and diagonal dual support decreased substantially following MPTP treatment (p < 0.05). All of these changes lasted for three weeks after the last MPTP administration. Except for the stance in the fore limbs and the swing speed in the hind limbs, the gait variability in the PD mice showed a closer correlation with the protein levels of TH in the SN than the walking distances in the conventional open field test. Coordination parameters of the regularity index and step pattern were not affected in mice treated with MPTP. Data of the study suggest that the computer-assisted CatWalk system can provide reliable and objective criteria to stratify gait changes arising from MPTP-induced bilateral lesions in C57/BL6 mice. The extent of gait changes was noted to correlate with the expression of the biomarker for dopaminergic neurons. This novel analytical method may hold promise in the study of disease progression and new drug screening in a murine PD model.
2012-01-01
Background Gait deficits are important clinical symptoms of Parkinson’s disease (PD). However, existing behavioral tests for the detection of motor impairments in rodents with systemic dopamine depletion only measure akinesia and dyskinesia, and data focusing on gait are scarce. We evaluated gait changes in the methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced C57BL/6 murine model of PD by using a computer-assisted CatWalk system. Correlations of gait parameters with tyrosine hydroxylase (TH) protein levels in the substantia nigra (SN) were also investigated. Results The gait readouts, including the walking duration, variation of walking speed, step cycle, duty cycle, stance, initial dual stance, terminal dual stance, three- and four-point supports, and the base of support between hind limbs was noted to increase significantly one week after MPTP injection. In contrast, values of the stride length, cadence, swing speed, and diagonal dual support decreased substantially following MPTP treatment (p < 0.05). All of these changes lasted for three weeks after the last MPTP administration. Except for the stance in the fore limbs and the swing speed in the hind limbs, the gait variability in the PD mice showed a closer correlation with the protein levels of TH in the SN than the walking distances in the conventional open field test. Coordination parameters of the regularity index and step pattern were not affected in mice treated with MPTP. Conclusion Data of the study suggest that the computer-assisted CatWalk system can provide reliable and objective criteria to stratify gait changes arising from MPTP-induced bilateral lesions in C57/BL6 mice. The extent of gait changes was noted to correlate with the expression of the biomarker for dopaminergic neurons. This novel analytical method may hold promise in the study of disease progression and new drug screening in a murine PD model. PMID:23151254
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
Hejrati, Babak; Chesebrough, Sam; Bo Foreman, K; Abbott, Jake J; Merryweather, Andrew S
2016-10-01
Previous studies have shown that inclusion of arm swing in gait rehabilitation leads to more effective walking recovery in patients with walking impairments. However, little is known about the correct arm-swing trajectories to be used in gait rehabilitation given the fact that changes in walking conditions affect arm-swing patterns. In this paper we present a comprehensive look at the effects of a variety of conditions on arm-swing patterns during walking. The results describe the effects of surface slope, walking speed, and physical characteristics on arm-swing patterns in healthy individuals. We propose data-driven mathematical models to describe arm-swing trajectories. Thirty individuals (fifteen females and fifteen males) with a wide range of height (1.58-1.91m) and body mass (49-98kg), participated in our study. Based on their self-selected walking speed, each participant performed walking trials with four speeds on five surface slopes while their whole-body kinematics were recorded. Statistical analysis showed that walking speed, surface slope, and height were the major factors influencing arm swing during locomotion. The results demonstrate that data-driven models can successfully describe arm-swing trajectories for normal gait under varying walking conditions. The findings also provide insight into the behavior of the elbow during walking. Copyright © 2016. Published by Elsevier B.V.
Lo, Wai Leung; Lin, Qiang; Xiao, Xiang; Raghavan, Preeti; Huang, Dong-Feng
2015-01-01
Objective. Gait performance is an indicator of mobility impairment after stroke. This study evaluated changes in balance, lower extremity motor function, and spatiotemporal gait parameters after receiving body weight supported treadmill training (BWSTT) and conventional overground walking training (CT) in patients with subacute stroke using 3D motion analysis. Setting. Inpatient department of rehabilitation medicine at a university-affiliated hospital. Participants. 24 subjects with unilateral hemiplegia in the subacute stage were randomized to the BWSTT (n = 12) and CT (n = 12) groups. Parameters were compared between the two groups. Data from twelve age matched healthy subjects were recorded as reference. Interventions. Patients received gait training with BWSTT or CT for an average of 30 minutes/day, 5 days/week, for 3 weeks. Main Outcome Measures. Balance was measured by the Brunel balance assessment. Lower extremity motor function was evaluated by the Fugl-Meyer assessment scale. Kinematic data were collected and analyzed using a gait capture system before and after the interventions. Results. Both groups improved on balance and lower extremity motor function measures (P < 0.05), with no significant difference between the two groups after intervention. However, kinematic data were significantly improved (P < 0.05) after BWSTT but not after CT. Maximum hip extension and flexion angles were significantly improved (P < 0.05) for the BWSTT group during the stance and swing phases compared to baseline. Conclusion. In subacute patients with stroke, BWSTT can lead to improved gait quality when compared with conventional gait training. Both methods can improve balance and motor function. PMID:26649295
Mao, Yu-Rong; Lo, Wai Leung; Lin, Qiang; Li, Le; Xiao, Xiang; Raghavan, Preeti; Huang, Dong-Feng
2015-01-01
Gait performance is an indicator of mobility impairment after stroke. This study evaluated changes in balance, lower extremity motor function, and spatiotemporal gait parameters after receiving body weight supported treadmill training (BWSTT) and conventional overground walking training (CT) in patients with subacute stroke using 3D motion analysis. Inpatient department of rehabilitation medicine at a university-affiliated hospital. 24 subjects with unilateral hemiplegia in the subacute stage were randomized to the BWSTT (n = 12) and CT (n = 12) groups. Parameters were compared between the two groups. Data from twelve age matched healthy subjects were recorded as reference. Patients received gait training with BWSTT or CT for an average of 30 minutes/day, 5 days/week, for 3 weeks. Balance was measured by the Brunel balance assessment. Lower extremity motor function was evaluated by the Fugl-Meyer assessment scale. Kinematic data were collected and analyzed using a gait capture system before and after the interventions. Both groups improved on balance and lower extremity motor function measures (P < 0.05), with no significant difference between the two groups after intervention. However, kinematic data were significantly improved (P < 0.05) after BWSTT but not after CT. Maximum hip extension and flexion angles were significantly improved (P < 0.05) for the BWSTT group during the stance and swing phases compared to baseline. In subacute patients with stroke, BWSTT can lead to improved gait quality when compared with conventional gait training. Both methods can improve balance and motor function.
Screw-Home Movement of the Tibiofemoral Joint during Normal Gait: Three-Dimensional Analysis
Kim, Ha Yong; Yang, Dae Suk; Jeung, Sang Wook; Choi, Han Gyeol; Choy, Won Sik
2015-01-01
Background 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. Methods 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 (Pf) and tibial coronal plane (Pt), 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 (Pf and Pt) during normal gait. Results 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°. Conclusions 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. PMID:26330951
Bartholdy, Cecilie; Schjoedt-Jorgensen, Tanja; Bliddal, Henning
2016-01-01
Aim To assess the effects of a functional and individualised exercise programme on gait biomechanics during walking in people with knee OA. Methods Sixty participants were randomised to 12 weeks of facility-based functional and individualised neuromuscular exercise therapy (ET), 3 sessions per week supervised by trained physical therapists, or a no attention control group (CG). Three-dimensional gait analyses were used, from which a comprehensive list of conventional gait variables were extracted (totally 52 kinematic, kinetic and spatiotemporal variables). According to the protocol, the analyses were based on the ‘Per-Protocol’ population (defined as participants following the protocol with complete and valid gait analyses). Analysis of covariance adjusting for the level at baseline was used to determine differences between groups (95% CIs) in the changes from baseline at follow-up. Results The per-protocol population included 46 participants (24 ET/22 CG). There were no group differences in the analysed gait variables, except for a significant group difference in the second peak knee flexor moment and second peak vertical ground reaction force. Conclusion While plausible we have limited confidence in the findings due to multiple statistical tests and lack of biomechanical logics. Therefore we conclude that a 12-week supervised individualised neuromuscular exercise programme has no effects on gait biomechanics. Future studies should focus on exercise programmes specifically designed to alter gait patterns, or include other measures of mobility, such as walking on stairs or inclined surfaces. Trial registration number ClinicalTrials.gov: NCT01545258. PMID:28879038
Does walking strategy in older people change as a function of walking distance?
Najafi, Bijan; Helbostad, Jorunn L; Moe-Nilssen, Rolf; Zijlstra, Wiebren; Aminian, Kamiar
2009-02-01
This study investigates whether the spatio-temporal parameters of gait in the elderly vary as a function of walking distance. The gait pattern of older subjects (n=27) over both short (SWD<10 m) and long (LWD>20 m) walking was evaluated using an ambulatory device consisting of body-worn sensors (Physilog). The stride velocity (SV), gait cycle time (GCT), and inter-cycle variability of each parameter (CV) were evaluated for each subject. Analysis was undertaken after evaluating the errors and the test-retest reliability of the Physilog device compared with an electronic walkway system (GaitRite) over the SWD with different walking speeds. While both systems were highly reliable with respect to the SV and GCT parameters (ICC>0.82), agreement for the gait variability was poor. Interestingly, our data revealed that the measured gait parameters over SWD and LWD were significantly different. LWD trials had a mean increase of 5.2% (p<0.05) in SV, and a mean decrease of 3.7% (p<0.05) in GCT compared with SWD trials. Although variability in both the SV and GCT measured during LWD trials decreased by an average of 1% relative to the SWD case, the drop was not significant. Moreover, reliability for gait variability measures was poor, irrespective of the instrument and despite a moderate improvement for LWD trials. Taken together, our findings indicate that for valid and reliable comparisons, test and retest should be performed under identical distance conditions. Furthermore, our findings suggest that the older subjects may choose different walking strategies for SWD and LWD conditions.
Behavioral and Neural Correlates of Imagined Walking and Walking-While-Talking in the Elderly
Blumen, Helena M.; Holtzer, Roee; Brown, Lucy L.; Gazes, Yunglin; Verghese, Joe
2014-01-01
Cognition is important for locomotion and gait decline increases the risk for morbidity, mortality, cognitive decline, and dementia. Yet, the neural correlates of gait are not well established, because most neuroimaging methods cannot image the brain during locomotion. Imagined gait protocols overcome this limitation. This study examined the behavioral and neural correlates of a new imagined gait protocol that involved imagined walking (iW), imagined talking (iT), and imagined walking-while-talking (iWWT). In Experiment 1, 82 cognitively-healthy older adults (M = 80.45) walked (W), iW, walked while talking (WWT) and iWWT. Real and imagined walking task times were strongly correlated, particularly real and imagined dual-task times (WWT and iWWT). In Experiment 2, 33 cognitively-healthy older adults (M = 73.03) iW, iT, and iWWT during functional Magnetic Resonance Imaging. A multivariate Ordinal Trend (OrT) Covariance analysis identified a pattern of brain regions that: 1) varied as a function of imagery task difficulty (iW, iT and iWWT), 2) involved cerebellar, precuneus, supplementary motor and other prefrontal regions, and 3) were associated with kinesthetic imagery ratings and behavioral performance during actual WWT. This is the first study to compare the behavioral and neural correlates of imagined gait in single and dual-task situations, an issue that is particularly relevant to elderly populations. These initial findings encourage further research and development of this imagined gait protocol as a tool for improving gait and cognition among the elderly. PMID:24522972
Gait coordination in pregnancy: transverse pelvic and thoracic rotations and their relative phase.
Wu, Wenhua; Meijer, Onno G; Lamoth, Claudine J C; Uegaki, Kimi; van Dieën, Jaap H; Wuisman, Paul I J M; de Vries, Johanna I P; Beek, Peter J
2004-06-01
To examine the effects of pregnancy on the coordination of transverse pelvic and thoracic rotations during gait. Gait of healthy pregnant women and nulligravidae was studied during treadmill walking at predetermined velocities ranging from 0.17 to 1.72 m/s. pelvis-thorax coordination during walking is altered in women with postpartum pregnancy-related pelvic girdle pain. This coordination has not been investigated in a healthy pregnant population. Comfortable walking velocity was established. Amplitudes of pelvic and thoracic rotations were calculated. Their coordination was characterized by relative Fourier phase and its standard deviation. Comfortable walking velocity was significantly reduced. The amplitudes of pelvic and thoracic rotations were somewhat reduced, with significantly smaller intra-individual standard deviations. Also pelvis-thorax relative Fourier phase was somewhat smaller, its intra-individual standard deviation was negatively correlated with week of pregnancy, and significantly lower at velocities > or = 1.06 m/s. The general pattern of gait kinematics in pregnant women is very similar to that of nulligravidae. Still, it appears that pregnant women experience difficulties in realizing the more anti-phase pelvis-thorax coordination that is required at higher walking velocities. The present study shows that gait in healthy pregnancy is remarkably normal, but some differences in pelvis-thorax coordination were detected. In healthy pregnancy, anti-phase pelvis-thorax coordination appears difficult, but less so than in pregnancy-related pelvic girdle pain. Better understanding of gait in healthy pregnancy may provide insight into the gait problems of women with pregnancy-related pelvic girdle pain. Copyright 2004 Elsevier Ltd.
Screw-Home Movement of the Tibiofemoral Joint during Normal Gait: Three-Dimensional Analysis.
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.
Substrate attributes determine gait in a terrestrial gastropod.
McKee, Amberle; Voltzow, Janice; Pernet, Bruno
2013-02-01
Some terrestrial gastropods are able to move using two gaits: adhesive crawling, where the entire foot is separated from the substrate only by a thin layer of mucus and the snail leaves a continuous mucus trail; and loping, where regions of the foot arch above the substrate and the snail leaves a discontinuous mucus trail. Loping has been interpreted as a means of rapidly escaping predators. We found that the pulmonate Cornu aspersum moved using adhesive crawling on dry acrylic or glass substrates, but loped on dry concrete or wood. Loping snails did not move more rapidly than snails using adhesive crawling. Snails moving on concrete secreted a greater volume of pedal mucus per area of trail than those moving on acrylic; locomotion on concrete thus requires greater expenditure of mucus than does locomotion on acrylic. Because loping snails deposit a smaller area of mucus per distance traveled than do snails using adhesive crawling, loping may conserve mucus when moving on porous, absorbent substrates. Members of several other terrestrial pulmonate taxa can also lope on concrete, suggesting that this plasticity in gait is widespread among terrestrial snails.
LSTM for diagnosis of neurodegenerative diseases using gait data
NASA Astrophysics Data System (ADS)
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
Schwartz, Isabella; Meiner, Zeev
2013-03-01
Regaining one's ability to walk is of great importance for neurological patients and is a major goal of all rehabilitation programs. Treating neurological patients in the acute phase after the event is technically difficult because of their motor weakness and balance disturbances. Based on studies in spinalized animals, a novel locomotor training that incorporates high repetitions of task-oriented practice by the use of body weight-supported treadmill training (BWSTT) was developed to overcome these obstacles. The use of BWSTT enables early initiation of gait training, integration of weightbearing activities, stepping and balance by the use of a task-specific approach, and a symmetrical gait pattern. However, despite the theoretical potential of BWSTT to become an invaluable therapeutic tool, its effect on walking outcomes was disappointing when compared with conventional training of the same duration. To facilitate the deLivery of BWSTT, a motorized robotic driven gait orthosis (RBWSTT) was recently developed. It has many advantages over the conventional method, including less effort for the physiotherapists, longer session duration, more physiological and reproducible gait patterns, and the possibility of measuring a patient's performances. Several studies have been conducted using RBWSTT in patients after stroke, spinal cord injury, multiple sclerosis and other neurological diseases. Although some of the results were encouraging, there is still uncertainty regarding proper patient selection, timing and protocol for RBWTT treatment following neurological diseases. More large randomized controlled studies are needed in order to answer these questions.
Halloran, Jason P; Ackermann, Marko; Erdemir, Ahmet; van den Bogert, Antonie J
2010-10-19
Current computational methods for simulating locomotion have primarily used muscle-driven multibody dynamics, in which neuromuscular control is optimized. Such simulations generally represent joints and soft tissue as simple kinematic or elastic elements for computational efficiency. These assumptions limit application in studies such as ligament injury or osteoarthritis, where local tissue loading must be predicted. Conversely, tissue can be simulated using the finite element method with assumed or measured boundary conditions, but this does not represent the effects of whole body dynamics and neuromuscular control. Coupling the two domains would overcome these limitations and allow prediction of movement strategies guided by tissue stresses. Here we demonstrate this concept in a gait simulation where a musculoskeletal model is coupled to a finite element representation of the foot. Predictive simulations incorporated peak plantar tissue deformation into the objective of the movement optimization, as well as terms to track normative gait data and minimize fatigue. Two optimizations were performed, first without the strain minimization term and second with the term. Convergence to realistic gait patterns was achieved with the second optimization realizing a 44% reduction in peak tissue strain energy density. The study demonstrated that it is possible to alter computationally predicted neuromuscular control to minimize tissue strain while including desired kinematic and muscular behavior. Future work should include experimental validation before application of the methodology to patient care. Copyright © 2010 Elsevier Ltd. All rights reserved.
Early signs of gait deviation in Duchenne muscular dystrophy.
Doglio, L; Pavan, E; Pernigotti, I; Petralia, P; Frigo, C; Minetti, C
2011-12-01
Most analytical studies found in literature only focus on specific aspects of Duchenne muscular dystrophy (DMD) gait and posture (joint range of motion, standing balance, variations of gait spatial-temporal parameters). Some of them analyze single cases and do not provide a comprehensive evaluation of locomotion. There are few studies about DMD gait patterns, most of them concerning small groups of patients, sometimes not homogeneous, in which the clinical manifestations of the next stages of DMD were present. The goal of our study was to analyze the characteristics of gait patterns in early stage patients, when clinical and functional evaluation do not allow to quantify initial walking worsening or to identify the changes adopted to compensate for muscle weakness. Gait Analysis Laboratory by using a six-camera motion capture system (Vicon, Oxford Metrics, UK), set at a sampling rate of 60 Hz. Subjects were asked to walk barefoot at their usual cadence, along a 10-m walkway, where one force platform (Kistler, Switzerland), embedded in the middle portion of the pathway, measured the foot-ground reaction forces. Retroreflective markers were placed on the subjects according to the protocol described in Davis et al. A group of 15 patients aging from 5 to 6.8 years was compared with a similar age control group composed of 9 healthy children. Spatial and temporal parameters showed significant differences between the two groups: cadence was increased and step length was decreased significantly in the DMD group. We found a significant increase in the range of anterior-posterior pelvic tilt and in pelvic rotation. In the frontal plane there was a tendency for an increased pelvic obliquity. Dynamic range of motion in sagittal plane showed a significant difference at the ankle, with an increased plantarflexion in swing in the dystrophic patients. Maximum dorsiflexion was reduced in the DMD group. Kinetic analysis showed significant differences in power generation and absorption at the hip joint and at the ankle joint. At knee there was a reduced flexor moment in mid-stance. Ankle showed a reduced dorsiflexor moment in terminal stance and pre-swing with a consequent reduction in the peak-to-peak excursion. It was shown that instrumented gait analysis, being more sensitive than other clinical and functional assessment methods, allowed to quantify the very early modifications characterizing locomotion worsening in the first stage of the DMD.
Mind your step: metabolic energy cost while walking an enforced gait pattern.
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.
Kinematic primitives for walking and trotting gaits of a quadruped robot with compliant legs.
Spröwitz, Alexander T; Ajallooeian, Mostafa; Tuleu, Alexandre; Ijspeert, Auke Jan
2014-01-01
In this work we research the role of body dynamics in the complexity of kinematic patterns in a quadruped robot with compliant legs. Two gait patterns, lateral sequence walk and trot, along with leg length control patterns of different complexity were implemented in a modular, feed-forward locomotion controller. The controller was tested on a small, quadruped robot with compliant, segmented leg design, and led to self-stable and self-stabilizing robot locomotion. In-air stepping and on-ground locomotion leg kinematics were recorded, and the number and shapes of motion primitives accounting for 95% of the variance of kinematic leg data were extracted. This revealed that kinematic patterns resulting from feed-forward control had a lower complexity (in-air stepping, 2-3 primitives) than kinematic patterns from on-ground locomotion (νm4 primitives), although both experiments applied identical motor patterns. The complexity of on-ground kinematic patterns had increased, through ground contact and mechanical entrainment. The complexity of observed kinematic on-ground data matches those reported from level-ground locomotion data of legged animals. Results indicate that a very low complexity of modular, rhythmic, feed-forward motor control is sufficient for level-ground locomotion in combination with passive compliant legged hardware.
Kinematic primitives for walking and trotting gaits of a quadruped robot with compliant legs
Spröwitz, Alexander T.; Ajallooeian, Mostafa; Tuleu, Alexandre; Ijspeert, Auke Jan
2014-01-01
In this work we research the role of body dynamics in the complexity of kinematic patterns in a quadruped robot with compliant legs. Two gait patterns, lateral sequence walk and trot, along with leg length control patterns of different complexity were implemented in a modular, feed-forward locomotion controller. The controller was tested on a small, quadruped robot with compliant, segmented leg design, and led to self-stable and self-stabilizing robot locomotion. In-air stepping and on-ground locomotion leg kinematics were recorded, and the number and shapes of motion primitives accounting for 95% of the variance of kinematic leg data were extracted. This revealed that kinematic patterns resulting from feed-forward control had a lower complexity (in-air stepping, 2–3 primitives) than kinematic patterns from on-ground locomotion (νm4 primitives), although both experiments applied identical motor patterns. The complexity of on-ground kinematic patterns had increased, through ground contact and mechanical entrainment. The complexity of observed kinematic on-ground data matches those reported from level-ground locomotion data of legged animals. Results indicate that a very low complexity of modular, rhythmic, feed-forward motor control is sufficient for level-ground locomotion in combination with passive compliant legged hardware. PMID:24639645
Perception of passage through openings depends on the size of the body in motion
Franchak, John M.; Celano, Emma C.; Adolph, Karen E.
2012-01-01
Walkers need to modify their ongoing actions to meet the demands of everyday environments. Navigating through openings requires gait modifications if the size of the opening is too small relative to the body. Here we ask if the spatial requirements for navigating horizontal and vertical openings differ, and, if so, whether walkers are sensitive to those requirements. To test walkers’ sensitivity to demands for gait modification, we asked participants to judge whether they could walk through horizontal openings without shoulder rotation and through vertical openings without ducking. Afterward, participants walked through the openings so that we could determine which opening sizes elicited gait modifications. Participants turned their shoulders with more space available than the space they left themselves for ducking. Larger buffers for horizontal openings may reflect different spatial requirements created by lateral sway of the body during walking compared to vertical bounce. In addition, greater variability of turning from trial to trial compared with ducking may lead walkers to adopt a more conservative buffer to avoid errors. Verbal judgments accurately predicted whether openings required gait modifications. For horizontal openings, participants’ judgments were best predicted by the body’s dynamic abilities, not static shoulder width. The differences between horizontal and vertical openings illustrate that walkers account for the dynamic properties of walking in addition to scaling decisions to body dimensions. PMID:22990292
Perception of passage through openings depends on the size of the body in motion.
Franchak, John M; Celano, Emma C; Adolph, Karen E
2012-11-01
Walkers need to modify their ongoing actions to meet the demands of everyday environments. Navigating through openings requires gait modifications if the size of the opening is too small relative to the body. Here we ask whether the spatial requirements for navigating horizontal and vertical openings differ, and, if so, whether walkers are sensitive to those requirements. To test walkers' sensitivity to demands for gait modification, we asked participants to judge whether they could walk through horizontal openings without shoulder rotation and through vertical openings without ducking. Afterward, participants walked through the openings, so that we could determine which opening sizes elicited gait modifications. Participants turned their shoulders with more space available than the space they left themselves for ducking. Larger buffers for horizontal openings may reflect different spatial requirements created by lateral sway of the body during walking compared to vertical bounce. In addition, greater variability of turning from trial to trial compared with ducking may lead walkers to adopt a more conservative buffer to avoid errors. Verbal judgments accurately predicted whether openings required gait modifications. For horizontal openings, participants' judgments were best predicted by the body's dynamic abilities, not static shoulder width. The differences between horizontal and vertical openings illustrate that walkers account for the dynamic properties of walking in addition to scaling decisions to body dimensions.
Is walking a random walk? Evidence for long-range correlations in stride interval of human gait
NASA Technical Reports Server (NTRS)
Hausdorff, Jeffrey M.; Peng, C.-K.; Ladin, Zvi; Wei, Jeanne Y.; Goldberger, Ary L.
1995-01-01
Complex fluctuation of unknown origin appear in the normal gait pattern. These fluctuations might be described as being (1) uncorrelated white noise, (2) short-range correlations, or (3) long-range correlations with power-law scaling. To test these possibilities, the stride interval of 10 healthy young men was measured as they walked for 9 min at their usual rate. From these time series we calculated scaling indexes by using a modified random walk analysis and power spectral analysis. Both indexes indicated the presence of long-range self-similar correlations extending over hundreds of steps; the stride interval at any time depended on the stride interval at remote previous times, and this dependence decayed in a scale-free (fractallike) power-law fashion. These scaling indexes were significantly different from those obtained after random shuffling of the original time series, indicating the importance of the sequential ordering of the stride interval. We demonstrate that conventional models of gait generation fail to reproduce the observed scaling behavior and introduce a new type of central pattern generator model that sucessfully accounts for the experimentally observed long-range correlations.
Farkas, Gary J; Schlink, Bryan R; Fogg, Louis F; Foucher, Kharma C; Wimmer, Markus A; Shakoor, Najia
2018-05-01
Little is known about the loading patterns in unilateral hip osteoarthritis (OA) and their relationship to radiographic severity and pain. We aimed to examine the loading patterns at the hips of those with unilateral symptomatic hip OA and identify associations between radiographic severity and pain with loading alterations. Sixty-one subjects with symptomatic unilateral hip OA underwent gait analyses and evaluation for radiographic severity (Kellgren-Lawrence [KL]-grade) and pain (visual analogue scale) at bilateral hips. Hip OA subjects had greater range of motion and higher hip flexion, adduction, internal and external rotation moments at the contralateral, asymptomatic hip compared to the ipsilateral hip ( p < 0.05). Correlations were noted between increasing KL-grade and increasing asymmetry of contralateral to ipsilateral hip loading ( p < 0.05). There were no relationships with pain and loading asymmetry. Unilateral symptomatic hip OA subjects demonstrate asymmetry in loading between the hips, with relatively greater loads at the contralateral hip. These loading asymmetries were directly related to the radiographic severity of symptomatic hip OA and not with pain. Additional research is needed to determine the role of gait asymmetries in disease progression.
Baby Carriage: Infants Walking with Loads
ERIC Educational Resources Information Center
Garciaguirre, Jessie S.; Adolph, Karen E.; Shrout, Patrick E.
2007-01-01
Maintaining balance is a central problem for new walkers. To examine how infants cope with the additional balance control problems induced by load carriage, 14-month-olds were loaded with 15% of their body weight in shoulder-packs. Both symmetrical and asymmetrical loads disrupted alternating gait patterns and caused less mature footfall patterns.…
The Effect of Auditory Cueing on the Spatial and Temporal Gait Coordination in Healthy Adults.
Almarwani, Maha; Van Swearingen, Jessie M; Perera, Subashan; Sparto, Patrick J; Brach, Jennifer S
2017-12-27
Walk ratio, defined as step length divided by cadence, indicates the coordination of gait. During free walking, deviation from the preferential walk ratio may reveal abnormalities of walking patterns. The purpose of this study was to examine the impact of rhythmic auditory cueing (metronome) on the neuromotor control of gait at different walking speeds. Forty adults (mean age 26.6 ± 6.0 years) participated in the study. Gait characteristics were collected using a computerized walkway. In the preferred walking speed, there was no significant difference in walk ratio between uncued (walk ratio = .0064 ± .0007 m/steps/min) and metronome-cued walking (walk ratio = .0064 ± .0007 m/steps/min; p = .791). A higher value of walk ratio at the slower speed was observed with metronome-cued (walk ratio = .0071 ± .0008 m/steps/min) compared to uncued walking (walk ratio = .0068 ± .0007 m/steps/min; p < .001). The walk ratio was less at faster speed with metronome-cued (walk ratio = .0060 ± .0009 m/steps/min) compared to uncued walking (walk ratio = .0062 ± .0009 m/steps/min; p = .005). In healthy adults, the metronome cues may become an attentional demanding task, and thereby disrupt the spatial and temporal integration of gait at nonpreferred speeds.
Solomonow-Avnon, Deborah; Levin, Daniel; Elboim-Gabyzon, Michal; Rozen, Nimrod; Peled, Eli; Wolf, Alon
2016-06-01
Footwear-generated medio-lateral foot center of pressure manipulation has been shown to have potential positive effects on gait parameters of hip osteoarthritis patients, ultimately reducing maximum joint reaction forces. The objective of this study was to investigate effects of medio-lateral foot center of pressure manipulation on muscle activity of hip-spanning and back muscles during gait in bilateral hip osteoarthritis patients. Foot center of pressure was shifted along the medio-lateral foot axis using a foot-worn biomechanical device allowing controlled center of pressure manipulation. Sixteen female bilateral hip osteoarthritis patients underwent electromyography analysis while walking in the device set to three parasagittal configurations: neutral (control), medial, and lateral. Seven hip-spanning muscles (Gluteus Medius, Gluteus Maximus, Tensor Fascia Latae, Rectus Femoris, Semitendinosis, Biceps Femoris, Adductor Magnus) and one back muscle (Erector Spinae) were analyzed. Magnitude and temporal parameters were calculated. The amplitude and temporal parameter varied significantly between foot center of pressure positions for 5 out of 8 muscles each for either the more or less symptomatic leg in at least one subphase of the gait cycle. Medio-lateral foot center of pressure manipulation significantly affects neuromuscular pattern of hip and back musculature during gait in female hip bilateral osteoarthritis patients. Copyright © 2016 Elsevier Ltd. All rights reserved.
Smith, Beth A.; Kubo, Masayoshi; Ulrich, Beverly D.
2012-01-01
The combined effects of ligamentous laxity, hypotonia, and decrements associated with aging lead to stability-enhancing foot placement adaptations during routine overground walking at a younger age in adults with Down syndrome (DS) compared to their peers with typical development (TD). Our purpose here was to examine real-time adaptations in older adults with DS by testing their responses to walking on a treadmill at their preferred speed and at speeds slower and faster than preferred. We found that older adults with DS were able to adapt their gait to slower and faster than preferred treadmill speeds; however, they maintained their stability-enhancing foot placements at all speeds compared to their peers with TD. All adults adapted their gait patterns similarly in response to faster and slower than preferred treadmill-walking speeds. They increased stride frequency and stride length, maintained step width, and decreased percent stance as treadmill speed increased. Older adults with DS, however, adjusted their stride frequencies significantly less than their peers with TD. Our results show that older adults with DS have the capacity to adapt their gait parameters in response to different walking speeds while also supporting the need for intervention to increase gait stability. PMID:22693497
Lerner, Zachary F; Damiano, Diane L; Bulea, Thomas C
2016-08-01
A robotic exoskeleton was designed for individuals with crouch gait caused by cerebral palsy with the intent to supplement existing muscle function during walking. The aim of this study was to evaluate how powered knee extension assistance provided during stance and swing phases of the gait cycle affect knee kinematics, and knee flexor and extensor muscle activity. Muscle activity and kinematic data were collected from four individuals with crouch gait from cerebral palsy during their normal walking condition and while walking with the exoskeleton under stance, swing, and stance & swing assistance. The exoskeleton was effective in reducing crouch by an average of 13.8° in three of the four participants when assistance was provided during the stance phase; assistance during the swing phase alone was ineffective. Peak knee extensor activity was maintained for all of the conditions during the stance and swing phases. Integrated (i.e. area under the curve) knee extensor activity decreased in two of the subjects indicating a more well-modulated activation pattern. Modest increases in peak and integrated antagonist knee flexor activity were exhibited in all participants; the subject without kinematic improvement had the greatest increase. While the exoskeleton was well tolerated, additional training with a focus on reducing knee flexor activity may lead to further improvements in crouch gait reduction.
Contribution of tibiofemoral joint contact to net loads at the knee in gait.
Walter, Jonathan P; Korkmaz, Nuray; Fregly, Benjamin J; Pandy, Marcus G
2015-07-01
Inverse dynamics analysis is commonly used to estimate the net loads at a joint during human motion. Most lower-limb models of movement represent the knee as a simple hinge joint when calculating muscle forces. This approach is limited because it neglects the contributions from tibiofemoral joint contact forces and may therefore lead to errors in estimated muscle forces. The aim of this study was to quantify the contributions of tibiofemoral joint contact loads to the net knee loads calculated from inverse dynamics for multiple subjects and multiple gait patterns. Tibiofemoral joint contact loads were measured in four subjects with instrumented implants as each subject walked at their preferred speed (normal gait) and performed prescribed gait modifications designed to treat medial knee osteoarthritis. Tibiofemoral contact loads contributed substantially to the net knee extension and knee adduction moments in normal gait with mean values of 16% and 54%, respectively. These findings suggest that knee-contact kinematics and loads should be included in lower-limb models of movement for more accurate determination of muscle forces. The results of this study may be used to guide the development of more realistic lower-limb models that account for the effects of tibiofemoral joint contact at the knee. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.
Walton, Courtney C; Shine, James M; Mowszowski, Loren; Gilat, Moran; Hall, Julie M; O'Callaghan, Claire; Naismith, Sharon L; Lewis, Simon J G
2015-05-01
Freezing of gait is a frequent and disabling symptom experienced by many patients with Parkinson's disease. A number of executive deficits have been shown to be associated with the phenomenon suggesting a common underlying pathophysiology, which as of yet remains unclear. Neuroimaging studies have also implicated the role of the cognitive control network in patients with freezing. To explore this concept, the current study examined error-monitoring as a measure of cognitive control. Thirty-four patients with and 38 without freezing of gait, who were otherwise well matched on disease severity, completed a colour-word interference task that allowed the specific assessment of error monitoring during conflict. Whilst both groups performed colour-naming and word-reading tasks equally well, those patients with freezing showed a pattern between conditions whereby they were better able to monitor performance and self-correct errors in the pure inhibition task but not after a switching rule was introduced. The novel results shown here provide insight into possible pathophysiological mechanisms involved in cognitive load and error monitoring in patients with freezing of gait. These results provide further evidence for the role of functional frontostriatal circuitry impairments in patients with freezing of gait and have implications for future studies and possible therapeutic interventions.
Metabolic, Cardiopulmonary, and Gait Profiles of Recently Injured and Noninjured Runners
Peng, Lucinda; Seay, Amanda N.; Montero, Cindy; Barnes, Leslie L.; Vincent, Kevin R.; Conrad, Bryan P.; Chen, Cong; Vincent, Heather K.
2017-01-01
Objective To examine whether runners recovering from a lower body musculoskeletal injury have different metabolic, cardiopulmonary, and gait responses compared with healthy runners. Design Cross-sectional study. Setting Research laboratory at an academic institution. Methods Healthy runners (n = 50) were compared with runners who were recently injured but had returned to running (n = 50). Both groups were participating in similar cross-training modalities such as swimming, weight training, biking, and yoga. Running gait was analyzed on a treadmill using 3-dimensional motion capture, and metabolic and cardiopulmonary measures were captured simultaneously with a portable metabolic analyzer. Main Outcome Measures Rate of oxygen consumption, heart rate, ventilation, carbohydrate and fat oxidation values, gait temporospatial parameters and range of motion measures (ROM) in the sagittal plane, energy expenditure, and vertical displacement of the body’s center of gravity (COG). Results The self-selected running speed was different between the injured and healthy runners (9.7 ± 1.1 km/h and 10.6 ± 1.1 km/h, respectively; P = .038). No significant group differences were noted in any metabolic or cardiopulmonary variable while running at the self-selected or standard speed (13.6 km/h). The vertical displacement of the COG was less in the injured group (8.4 ± 1.4 cm and 8.9 ± 1.4, respectively; P = .044). ROM about the right ankle in the sagittal plane at the self-selected running speed during the gait cycle was less in the injured runners compared with the healthy runners (P < .05). Conclusions Runners with a recent lower body injury who have returned to running have similar cardiopulmonary and metabolic responses to running as healthy runners at the self-selected and standard speeds; this finding may be due in part to participation in cross-training modes that preserve cardiopulmonary and metabolic adaptations. Injured runners may conserve motion by minimizing COG displacement and ankle joint ROM during a gait cycle. PMID:24998402
Acetabular cartilage defects cause altered hip and knee joint coordination variability during gait.
Samaan, Michael A; Teng, Hsiang-Ling; Kumar, Deepak; Lee, Sonia; Link, Thomas M; Majumdar, Sharmila; Souza, Richard B
2015-12-01
Patients with acetabular cartilage defects reported increased pain and disability compared to those without acetabular cartilage defects. The specific effects of acetabular cartilage defects on lower extremity coordination patterns are unclear. The purpose of this study was to determine hip and knee joint coordination variability during gait in those with and without acetabular cartilage defects. A combined approach, consisting of a semi-quantitative MRI-based quantification method and vector coding, was used to assess hip and knee joint coordination variability during gait in those with and without acetabular cartilage lesions. The coordination variability of the hip flexion-extension/knee rotation, hip abduction-adduction/knee rotation, and hip rotation/knee rotation joint couplings were reduced in the acetabular lesion group compared to the control group during loading response of the gait cycle. The lesion group demonstrated increased variability in the hip flexion-extension/knee rotation and hip abduction-adduction/knee rotation joint couplings, compared to the control group, during the terminal stance/pre-swing phase of gait. Reduced variability during loading response in the lesion group may suggest reduced movement strategies and a possible compensation mechanism for lower extremity instability during this phase of the gait cycle. During terminal stance/pre-swing, a larger variability in the lesion group may suggest increased movement strategies and represent a compensation or pain avoidance mechanism caused by the load applied to the hip joint. Copyright © 2015 Elsevier Ltd. All rights reserved.
Kosse, Nienke M; Caljouw, Simone; Vervoort, Danique; Vuillerme, Nicolas; Lamoth, Claudine J C
2015-08-01
Accelerometer-based assessments can identify elderly with an increased fall risk and monitor interventions. Smart devices, like the iPod Touch, with built-in accelerometers are promising for clinical gait and posture assessments due to easy use and cost-effectiveness. The aim of the present study was to establish the validity and reliability of the iPod Touch for gait and posture assessment. Sixty healthy participants (aged 18-75 years) were measured with an iPod Touch and stand-alone accelerometer while they walked under single- and dual-task conditions, and while standing in parallel and semi-tandem stance with eyes open, eyes closed and when performing a dual task. Cross-correlation values (CCV) showed high correspondence of anterior-posterior and medio-lateral signal patterns (CCV's ≥ 0.88). Validity of gait parameters (foot contacts, index of harmonicity, and amplitude variability) and standing posture parameters [root mean square of accelerations, median power frequency (MPF) and sway area] as indicated by intra-class correlation (ICC) was high (ICC = 0.85-0.99) and test-retest reliability was good (ICC = 0.81-0.97), except for MPF (ICC = 0.59-0.87). Overall, the iPod Touch obtained valid and reliable measures of gait and postural control in healthy adults of all ages under different conditions. Additionally, smart devices have the potential to be used for clinical gait and posture assessments.
Ganley, Kathleen J; Powers, Christopher M
2005-02-01
The purpose of this study was to determine if sagittal plane gait kinematics and kinetics of 7-year-old children differed from those of adults when age-specific anthropometrics were used in the calculations. Joint angles, moments, and power obtained during level walking in 7-year-old children (n=15) were compared to data from adults (n=15). Calculations were performed using age-specific anthropometric data obtained from dual energy X-ray absorptiometry. For most of the variables examined, 7-year-olds were similar to adults, however children demonstrated a diminished peak plantar flexor moment and less peak power absorption and generation at the ankle during late stance. These results provide support for the hypothesis that children lack the neuromuscular maturity, especially at the ankle, to produce an adult-like gait pattern.
Balance control during gait initiation: State-of-the-art and research perspectives.
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.
Carmo, A.A.; Kleiner, A.F.R.; Lobo da Costa, P.H.; Barros, R.M.L.
2012-01-01
The aim of this study was to analyze the alterations of arm and leg movements of patients during stroke gait. Joint angles of upper and lower limbs and spatiotemporal variables were evaluated in two groups: hemiparetic group (HG, 14 hemiparetic men, 53 ± 10 years) and control group (CG, 7 able-bodied men, 50 ± 4 years). The statistical analysis was based on the following comparisons (P ≤ 0.05): 1) right versus left sides of CG; 2) affected (AF) versus unaffected (UF) sides of HG; 3) CG versus both the affected and unaffected sides of HG, and 4) an intracycle comparison of the kinematic continuous angular variables between HG and CG. This study showed that the affected upper limb motion in stroke gait was characterized by a decreased range of motion of the glenohumeral (HG: 6.3 ± 4.5, CG: 20.1 ± 8.2) and elbow joints (AF: 8.4 ± 4.4, UF: 15.6 ± 7.6) on the sagittal plane and elbow joint flexion throughout the cycle (AF: 68.2 ± 0.4, CG: 46.8 ± 2.7). The glenohumeral joint presented a higher abduction angle (AF: 14.2 ± 1.6, CG: 11.5 ± 4.0) and a lower external rotation throughout the cycle (AF: 4.6 ± 1.2, CG: 22.0 ± 3.0). The lower limbs showed typical alterations of the stroke gait patterns. Thus, the changes in upper and lower limb motion of stroke gait were identified. The description of upper limb motion in stroke gait is new and complements gait analysis. PMID:22473324
Jagos, Harald; Pils, Katharina; Haller, Michael; Wassermann, Claudia; Chhatwal, Christa; Rafolt, Dietmar; Rattay, Frank
2017-07-01
Clinical gait analysis contributes massively to rehabilitation support and improvement of in-patient care. The research project eSHOE aspires to be a useful addition to the rich variety of gait analysis systems. It was designed to fill the gap of affordable, reasonably accurate and highly mobile measurement devices. With the overall goal of enabling individual home-based monitoring and training for people suffering from chronic diseases, affecting the locomotor system. Motion and pressure sensors gather movement data directly on the (users) feet, store them locally and/or transmit them wirelessly to a PC. A combination of pattern recognition and feature extraction algorithms translates the motion data into standard gait parameters. Accuracy of eSHOE were evaluated against the reference system GAITRite in a clinical pilot study. Eleven hip fracture patients (78.4 ± 7.7 years) and twelve healthy subjects (40.8 ± 9.1 years) were included in these trials. All subjects performed three measurements at a comfortable walking speed over 8 m, including the 6-m long GAITRite mat. Six standard gait parameters were extracted from a total of 347 gait cycles. Agreement was analysed via scatterplots, histograms and Bland-Altman plots. In the patient group, the average differences between eSHOE and GAITRite range from -0.046 to 0.045 s and in the healthy group from -0.029 to 0.029 s. Therefore, it can be concluded that eSHOE delivers adequately accurate results. Especially with the prospect as an at home supplement or follow-up to clinical gait analysis and compared to other state of the art wearable motion analysis systems.
Gait adaptations to awareness and experience of a slip when walking on a cross-slope.
Lawrence, Daniel; Domone, Sarah; Heller, Ben; Hendra, Timothy; Mawson, Susan; Wheat, Jon
2015-10-01
Falls that occur as a result of a slip are one of the leading causes of injuries, particularly in the elderly population. Previous studies have focused on slips that occur on a flat surface. Slips on a laterally sloping surface are important and may be related to different mechanisms of balance recovery. This type of slip might result in different gait adaptations to those previously described on a flat surface, but these adaptations have not been investigated. The aim of this study was to assess whether, when walking on a cross-slope, young adults adapted their gait when made aware of a potential slip, and having experienced a slip. Gait parameters were compared for three conditions--(1) Normal walking; (2) Walking after being made aware of a potential slip (participants were told that a slip may occur); (3) Walking after experiencing a slip (Participants had already experienced at least one slip induced using a soapy contaminant). Gait parameters were only analysed for trials in which there was no slippery contaminant present on the walkway. Stride length and walking velocity were significantly reduced, and stance duration was significantly greater in the awareness and experience conditions compared to normal walking, with no significant differences in any gait parameters between the awareness and experience conditions. In addition, 46.7% of the slip trials resulted in a fall. This is higher than reported for slips induced on a flat surface, suggesting slips on a cross-slope are more hazardous. This would help explain the more cautious gait patterns observed in both the awareness and experience conditions. Copyright © 2015 Elsevier B.V. All rights reserved.
Lerner, Zachary F; Damiano, Diane L; Park, Hyung-Soon; Gravunder, Andrew J; Bulea, Thomas C
2017-06-01
Crouch gait, a pathological pattern of walking characterized by excessive knee flexion, is one of the most common gait disorders observed in children with cerebral palsy (CP). Effective treatment of crouch during childhood is critical to maintain mobility into adulthood, yet current interventions do not adequately alleviate crouch in most individuals. Powered exoskeletons provide an untapped opportunity for intervention. The multiple contributors to crouch, including spasticity, contracture, muscle weakness, and poor motor control make design and control of such devices challenging in this population. To our knowledge, no evidence exists regarding the feasibility or efficacy of utilizing motorized assistance to alleviate knee flexion in crouch gait. Here, we present the design of and first results from a powered exoskeleton for extension assistance as a treatment for crouch gait in children with CP. Our exoskeleton, based on the architecture of a knee-ankle-foot orthosis, is lightweight (3.2 kg) and modular. On board sensors enable knee extension assistance to be provided during distinct phases of the gait cycle. We tested our device on one six-year-old male participant with spastic diplegia from CP. Our results show that the powered exoskeleton improved knee extension during stance by 18.1° while total knee range of motion improved 21.0°. Importantly, we observed no significant decrease in knee extensor muscle activity, indicating the user did not rely solely on the exoskeleton to extend the limb. These results establish the initial feasibility of robotic exoskeletons for treatment of crouch and provide impetus for continued investigation of these devices with the aim of deployment for long term gait training in this population.
Response of the arterial blood pressure of quadriplegic patients to treadmill gait training.
Carvalho, D C L; Cliquet, A
2005-09-01
Blood pressure pattern was analyzed in 12 complete quadriplegics with chronic lesions after three months of treadmill gait training. Before training, blood pressure values were obtained at rest, during treadmill walking and during the recovery phase. Gait training was performed for 20 min twice a week for three months. Treadmill gait was achieved using neuromuscular electrical stimulation, assisted by partial body weight relief (30-50%). After training, blood pressure was evaluated at rest, during gait and during recovery phase. Before and after training, mean systolic blood pressures and heart rates increased significantly during gait compared to rest (94.16 +/- 5.15 to 105 +/- 5.22 mmHg and 74.27 +/- 10.09 to 106.23 +/- 17.31 bpm, respectively), and blood pressure decreased significantly in the recovery phase (86.66 +/- 9.84 and 57.5 +/- 8.66 mmHg, respectively). After three months of training, systolic blood pressure became higher at rest (94.16 +/- 5.15 mmHg before training and 100 +/- 8.52 mmHg after training; P < 0.05) and during gait exercise (105 +/- 5.22 mmHg before and 110 +/- 7.38 mmHg after training; P < 0.05) when compared to the initial values, with no changes in heart rate. No changes occurred in blood pressure during the recovery phase, with the lower values being maintained. A drop in systolic pressure from 105 +/- 5.22 to 86.66 +/- 9.84 mmHg before training and from 110 +/- 7.38 to 90 +/- 7.38 mmHg after training was noticed immediately after exercise, thus resulting in hypotensive symptoms when chronic quadriplegics reach the sitting position from the upright position.
Gait post-stroke: Pathophysiology and rehabilitation strategies.
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.
Balance control during gait initiation: State-of-the-art and research perspectives
Yiou, Eric; Caderby, Teddy; Delafontaine, Arnaud; Fourcade, Paul; Honeine, Jean-Louis
2017-01-01
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. PMID:29184756
Wuehr, M; Schniepp, R; Pradhan, C; Ilmberger, J; Strupp, M; Brandt, T; Jahn, K
2013-01-01
Healthy persons exhibit relatively small temporal and spatial gait variability when walking unimpeded. In contrast, patients with a sensory deficit (e.g., polyneuropathy) show an increased gait variability that depends on speed and is associated with an increased fall risk. The purpose of this study was to investigate the role of vision in gait stabilization by determining the effects of withdrawing visual information (eyes closed) on gait variability at different locomotion speeds. Ten healthy subjects (32.2 ± 7.9 years, 5 women) walked on a treadmill for 5-min periods at their preferred walking speed and at 20, 40, 70, and 80 % of maximal walking speed during the conditions of walking with eyes open (EO) and with eyes closed (EC). The coefficient of variation (CV) and fractal dimension (α) of the fluctuations in stride time, stride length, and base width were computed and analyzed. Withdrawing visual information increased the base width CV for all walking velocities (p < 0.001). The effects of absent visual information on CV and α of stride time and stride length were most pronounced during slow locomotion (p < 0.001) and declined during fast walking speeds. The results indicate that visual feedback control is used to stabilize the medio-lateral (i.e., base width) gait parameters at all speed sections. In contrast, sensory feedback control in the fore-aft direction (i.e., stride time and stride length) depends on speed. Sensory feedback contributes most to fore-aft gait stabilization during slow locomotion, whereas passive biomechanical mechanisms and an automated central pattern generation appear to control fast locomotion.
Reinforcement learning of periodical gaits in locomotion robots
NASA Astrophysics Data System (ADS)
Svinin, Mikhail; Yamada, Kazuyaki; Ushio, S.; Ueda, Kanji
1999-08-01
Emergence of stable gaits in locomotion robots is studied in this paper. A classifier system, implementing an instance- based reinforcement learning scheme, is used for sensory- motor control of an eight-legged mobile robot. Important feature of the classifier system is its ability to work with the continuous sensor space. The robot does not have a prior knowledge of the environment, its own internal model, and the goal coordinates. It is only assumed that the robot can acquire stable gaits by learning how to reach a light source. During the learning process the control system, is self-organized by reinforcement signals. Reaching the light source defines a global reward. Forward motion gets a local reward, while stepping back and falling down get a local punishment. Feasibility of the proposed self-organized system is tested under simulation and experiment. The control actions are specified at the leg level. It is shown that, as learning progresses, the number of the action rules in the classifier systems is stabilized to a certain level, corresponding to the acquired gait patterns.
Development of quadruped walking locomotion gait generator using a hybrid method
NASA Astrophysics Data System (ADS)
Jasni, F.; Shafie, A. A.
2013-12-01
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.
Chien, Hui-Lien; Lu, Tung-Wu; Liu, Ming-Wei
2013-07-01
High-heeled shoes are associated with instability and falling, leading to injuries such as fracture and ankle sprain. Knowledge of the motion of the body's center of mass (COM) with respect to the center of pressure (COP) during high-heeled gait may offer insights into the balance control strategies and provide a basis for approaches that minimize the risk of falling and associated adverse effects. The study aimed to investigate the influence of the base and height of the heels on the COM motion in terms of COM-COP inclination angles (IA) and the rate of change of IA (RCIA). Fifteen females who regularly wear high heels walked barefoot and with narrow-heeled shoes with three heel heights (3.9cm, 6.3cm and 7.3cm) while kinematic and ground reaction force data were measured and used to calculate the COM and COP, as well as the temporal-distance parameters. The reduced base of the heels was found to be the primary factor for the reduced normalized walking speed and the reduced frontal IA throughout the gait cycle. This was achieved mainly through the control of the RCIA during double-leg stance (DLS). The heel heights affected mainly the peak RCIA during DLS, which were not big enough to affect the IA. These results suggest young adults adopt a conservative strategy for balance control during narrow-heeled gait. The results will serve as baseline data for future evaluation of patients and/or older adults during narrow-heeled gait with the aim of reducing the risk of falling. Copyright © 2012 Elsevier B.V. All rights reserved.
Menz, Hylton B; Auhl, Maria; Munteanu, Shannon E
2017-09-11
Footwear has the potential to influence balance in either a detrimental or beneficial manner, and is therefore an important consideration in relation to falls prevention. The objective of this study was to evaluate balance ability and gait patterns in older women while wearing prototype footwear and insoles designed to improve 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 on a foam rubber mat, limits of stability and tandem walking, measured with the Neurocom® Balance Master) and gait patterns (walking speed, cadence, step length and step width at preferred speed, measured with the GAITRite® walkway) while wearing (i) flexible footwear (Dunlop Volley™), (ii) their own footwear, and (iii) prototype footwear and insoles designed to improve dynamic balance. Perceptions of the footwear were also documented using a structured questionnaire. There was no difference in postural sway, limits of stability or gait patterns between the footwear conditions. However, when performing the tandem walking test, there was a significant reduction in step width and end sway when wearing the prototype footwear compared to both the flexible footwear and participants' own footwear. Participants perceived their own footwear to be more attractive, comfortable, well-fitted and easier to put on and off compared to the prototype footwear. Despite this, most participants (n = 18, 60%) reported that they would consider wearing the prototype footwear to reduce their risk of falling. The prototype footwear and insoles used in this study improve balance when performing a tandem walk test, as evidenced by a narrower step width and decreased sway at completion of the task. However, further development of the design is required to make the footwear acceptable to older women from the perspective of aesthetics and comfort. Australian New Zealand Clinical Trials Registry. ACTRN12617001128381 , 01/08/2017 (retrospectively registered).
Powered ankle-foot prosthesis to assist level-ground and stair-descent gaits.
Au, Samuel; Berniker, Max; Herr, Hugh
2008-05-01
The human ankle varies impedance and delivers net positive work during the stance period of walking. In contrast, commercially available ankle-foot prostheses are passive during stance, causing many clinical problems for transtibial amputees, including non-symmetric gait patterns, higher gait metabolism, and poorer shock absorption. In this investigation, we develop and evaluate a myoelectric-driven, finite state controller for a powered ankle-foot prosthesis that modulates both impedance and power output during stance. The system employs both sensory inputs measured local to the external prosthesis, and myoelectric inputs measured from residual limb muscles. Using local prosthetic sensing, we first develop two finite state controllers to produce biomimetic movement patterns for level-ground and stair-descent gaits. We then employ myoelectric signals as control commands to manage the transition between these finite state controllers. To transition from level-ground to stairs, the amputee flexes the gastrocnemius muscle, triggering the prosthetic ankle to plantar flex at terminal swing, and initiating the stair-descent state machine algorithm. To transition back to level-ground walking, the amputee flexes the tibialis anterior muscle, triggering the ankle to remain dorsiflexed at terminal swing, and initiating the level-ground state machine algorithm. As a preliminary evaluation of clinical efficacy, we test the device on a transtibial amputee with both the proposed controller and a conventional passive-elastic control. We find that the amputee can robustly transition between the finite state controllers through direct muscle activation, allowing rapid transitioning from level-ground to stair walking patterns. Additionally, we find that the proposed finite state controllers result in a more biomimetic ankle response, producing net propulsive work during level-ground walking and greater shock absorption during stair descent. The results of this study highlight the potential of prosthetic leg controllers that exploit neural signals to trigger terrain-appropriate, local prosthetic leg behaviors.
Roca-Dols, Andrea; Losa-Iglesias, Marta Elena; Sánchez-Gómez, Rubén; López-López, Daniel; Becerro-de-Bengoa-Vallejo, Ricardo; Calvo-Lobo, César
2018-06-01
Peroneus longus and brevis (PLB) disorders are commonly in people with lateral ligamentous instability, ankle pain, lateral hindfoot pain and structures of the proximal compartment of the lower legs and their muscle activity is believed to be influenced by different footwear types. The proposal of this research is to evaluate the effects of five types of footwear with respect to the barefoot condition and analyze the activity patterns of PLB muscles in healthy subjects during the gait cycle. Thirty healthy subjects were recruited in a laboratory in this cross-sectional research design. While walking, electromyography (EMG) activity was measured from PLB via surface electrodes in six experimental conditions: 1) barefoot, 2) minimalist, 3) pronated control, 4) air chamber, 5) ethyl-vinyl-acetate (EVA) and 6) boost. These data were obtained and compared. The peroneus brevis showed significant reductions in the peak amplitude of the five footwear types (minimalist, pronation control, air chamber, EVA and boost) with respect to the barefoot condition in the propulsion phase of the gait cycle during walking (P = 0.034; P < 0.001; P < 0.001; P < 0.001; P = 0.006) and running (P = 0.004; P < 0.001; P = 0.001; P < 0.001; P = 0.001), respectively. Furthermore, peroneus longus showed significant reductions in the peak amplitude of these five footwear types with respect to the barefoot condition in the propulsion phase of the gait cycle during running (P = 0.005; P = 0.038; P = 0.019; P = 0.025; P = 0.021). The EMG activity patterns of the PLB muscles may depend on the use of different types of sport shoes such as minimalist, pronation control, air chamber, EVA and boost footwear with respect the barefoot condition in different phases of the gait cycle during walking and running. Copyright © 2018 Elsevier Ltd. All rights reserved.
Yang, Wen-Chieh; Hsu, Wei-Li; Wu, Ruey-Meei; Lin, Kwan-Hwa
2016-10-01
Turning difficulty is common in people with Parkinson disease (PD). The clock-turn strategy is a cognitive movement strategy to improve turning performance in people with PD despite its effects are unverified. Therefore, this study aimed to investigate the effects of the clock-turn strategy on the pattern of turning steps, turning performance, and freezing of gait during a narrow turning, and how these effects were influenced by concurrent performance of a cognitive task (dual task). Twenty-five people with PD were randomly assigned to the clock-turn or usual-turn group. Participants performed the Timed Up and Go test with and without concurrent cognitive task during the medication OFF period. The clock-turn group performed the Timed Up and Go test using the clock-turn strategy, whereas participants in the usual-turn group performed in their usual manner. Measurements were taken during the 180° turn of the Timed Up and Go test. The pattern of turning steps was evaluated by step time variability and step time asymmetry. Turning performance was evaluated by turning time and number of turning steps. The number and duration of freezing of gait were calculated by video review. The clock-turn group had lower step time variability and step time asymmetry than the usual-turn group. Furthermore, the clock-turn group turned faster with fewer freezing of gait episodes than the usual-turn group. Dual task increased the step time variability and step time asymmetry in both groups but did not affect turning performance and freezing severity. The clock-turn strategy reduces turning time and freezing of gait during turning, probably by lowering step time variability and asymmetry. Dual task compromises the effects of the clock-turn strategy, suggesting a competition for attentional resources.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, http://links.lww.com/JNPT/A141).
Rosenlund, Signe; Broeng, Leif; Overgaard, Søren; Jensen, Carsten; Holsgaard-Larsen, Anders
2016-11-01
The lateral and the posterior approach are the most commonly used procedures for total hip arthroplasty. Due to the detachment of the hip abductors, lateral approach is claimed to cause reduced hip muscle strength and altered gait pattern. However, this has not been investigated in a randomised controlled trial. The aim was to compare the efficacy of total hip arthroplasty performed by lateral or posterior approach on gait function and hip muscle strength up to 12months post-operatively. We hypothesised that posterior approach would be superior to lateral approach. Forty-seven patients with primary hip osteoarthritis were randomised to total hip arthroplasty with either posterior or lateral approach and evaluated pre-operatively, 3 and 12months post-operatively using 3-dimensional gait analyses as objective measures of gait function, including Gait Deviation Index, temporo-spatial parameters and range of motion. Isometric maximal hip muscle strength in abduction, flexion and extension was also tested. Post-operatively, no between-group difference in gait function was observed. However, both hip abductor and flexor muscle strength improved more in the posterior approach group: -0.20(Nm/kg)[95%CI:-0.4 to 0.0] and -0.20(Nm/kg)[95%CI:-0.4 to 0.0], respectively. Contrary to our first hypothesis, the overall gait function in the posterior approach group did not improve more than in the lateral approach group. However, in agreement with our second hypothesis, patients in the posterior approach group improved more in hip abductor and flexor muscle strength at 12months. Further investigation of the effect of reduced maximal hip muscle strength on functional capacity is needed. ClinicalTrials.gov. No.: NCT01616667. Copyright © 2016 Elsevier Ltd. All rights reserved.
Houdijk, Han; van Ooijen, Mariëlle W; Kraal, Jos J; Wiggerts, Henri O; Polomski, Wojtek; Janssen, Thomas W J; Roerdink, Melvyn
2012-11-01
Gait adaptability, including the ability to avoid obstacles and to take visually guided steps, is essential for safe movement through a cluttered world. This aspect of walking ability is important for regaining independent mobility but is difficult to assess in clinical practice. The objective of this study was to investigate the validity of an instrumented treadmill with obstacles and stepping targets projected on the belt's surface for assessing prosthetic gait adaptability. This was an observational study. A control group of people who were able bodied (n=12) and groups of people with transtibial (n=12) and transfemoral (n=12) amputations participated. Participants walked at a self-selected speed on an instrumented treadmill with projected visual obstacles and stepping targets. Gait adaptability was evaluated in terms of anticipatory and reactive obstacle avoidance performance (for obstacles presented 4 steps and 1 step ahead, respectively) and accuracy of stepping on regular and irregular patterns of stepping targets. In addition, several clinical tests were administered, including timed walking tests and reports of incidence of falls and fear of falling. Obstacle avoidance performance and stepping accuracy were significantly lower in the groups with amputations than in the control group. Anticipatory obstacle avoidance performance was moderately correlated with timed walking test scores. Reactive obstacle avoidance performance and stepping accuracy performance were not related to timed walking tests. Gait adaptability scores did not differ in groups stratified by incidence of falls or fear of falling. Because gait adaptability was affected by walking speed, differences in self-selected walking speed may have diminished differences in gait adaptability between groups. Gait adaptability can be validly assessed by use of an instrumented treadmill with a projected visual context. When walking speed is taken into account, this assessment provides unique, quantitative information about walking ability in people with a lower-limb amputation.
Terrier, Philippe; Dériaz, Olivier
2013-01-01
It has been observed that times series of gait parameters [stride length (SL), stride time (ST), and stride speed (SS)], exhibit long-term persistence and fractal-like properties. Synchronizing steps with rhythmic auditory stimuli modifies the persistent fluctuation pattern to anti-persistence. Another non-linear method estimates the degree of resilience of gait control to small perturbations, i.e., the local dynamic stability (LDS). The method makes use of the maximal Lyapunov exponent, which estimates how fast a non-linear system embedded in a reconstructed state space (attractor) diverges after an infinitesimal perturbation. We propose to use an instrumented treadmill to simultaneously measure basic gait parameters (time series of SL, ST, and SS from which the statistical persistence among consecutive strides can be assessed), and the trajectory of the center of pressure (from which the LDS can be estimated). In 20 healthy participants, the response to rhythmic auditory cueing (RAC) of LDS and of statistical persistence [assessed with detrended fluctuation analysis (DFA)] was compared. By analyzing the divergence curves, we observed that long-term LDS (computed as the reverse of the average logarithmic rate of divergence between the 4th and the 10th strides downstream from nearest neighbors in the reconstructed attractor) was strongly enhanced (relative change +73%). That is likely the indication of a more dampened dynamics. The change in short-term LDS (divergence over one step) was smaller (+3%). DFA results (scaling exponents) confirmed an anti-persistent pattern in ST, SL, and SS. Long-term LDS (but not short-term LDS) and scaling exponents exhibited a significant correlation between them (r = 0.7). Both phenomena probably result from the more conscious/voluntary gait control that is required by RAC. We suggest that LDS and statistical persistence should be used to evaluate the efficiency of cueing therapy in patients with neurological gait disorders.
Licence, Sammy; Smith, Robynne; McGuigan, Miranda P.; Earnest, Conrad P.
2015-01-01
Objectives Mobile phone texting is a common daily occurrence with a paucity of research examining corresponding gait characteristics. To date, most studies have participants walk in a straight line vs. overcoming barriers and obstacles that occur during regular walking. The aim of our study is to examine the effect of mobile phone texting during periods of cognitive distraction while walking and negotiating barriers synonymous with pedestrian traffic. Methods Thirty participants (18-50y) completed three randomized, counter-balanced walking tasks over a course during: (1) normal walking (control), (2) texting and walking, and (3) texting and walking whilst being cognitively distraction via a standard mathematical test performed while negotiating the obstacle course. We analyzed gait characteristics during course negotiation using a 3-dimensional motion analysis system and a general linear model and Dunnet-Hsu post-hoc procedure the normal walking condition to assess gait characteristic differences. Primary outcomes included the overall time to complete the course time and barrier contact. Secondary outcomes included obstacle clearance height, step frequency, step time, double support phase and lateral deviation. Results Participants took significantly longer (mean ± SD) to complete the course while texting (24.96±4.20 sec) and during cognitive distraction COG (24.09±3.36 sec) vs. normal walking (19.32±2.28 sec; all, P<0.001). No significant differences were noted for barrier contacts (P = 0.28). Step frequency, step time, double support phase and lateral deviation all increased in duration during the texting and cognitive distraction trial. Texting and being cognitively distracted also increased obstacle clearance versus the walking condition (all, P<0.02). Conclusions Texting while walking and/or being cognitively distracted significantly affect gait characteristics concordant to mobile phone usage resulting in a more cautious gate pattern. Future research should also examine a similar study in older participants who may be at a greater risk of tripping with such walking deviations. PMID:26222430
Bicycling suppresses abnormal beta synchrony in the Parkinsonian basal ganglia.
Storzer, Lena; Butz, Markus; Hirschmann, Jan; Abbasi, Omid; Gratkowski, Maciej; Saupe, Dietmar; Vesper, Jan; Dalal, Sarang S; Schnitzler, Alfons
2017-10-01
Freezing of gait is a poorly understood symptom of Parkinson disease, and can severely disrupt the locomotion of affected patients. However, bicycling ability remains surprisingly unaffected in most patients suffering from freezing, suggesting functional differences in the motor network. The purpose of this study was to characterize and contrast the oscillatory dynamics underlying bicycling and walking in the basal ganglia. We present the first local field potential recordings directly comparing bicycling and walking in Parkinson disease patients with electrodes implanted in the subthalamic nuclei for deep brain stimulation. Low (13-22Hz) and high (23-35Hz) beta power changes were analyzed in 22 subthalamic nuclei from 13 Parkinson disease patients (57.5 ± 5.9 years old, 4 female). The study group consisted of 5 patients with and 8 patients without freezing of gait. In patients without freezing of gait, both bicycling and walking led to a suppression of subthalamic beta power (13-35Hz), and this suppression was stronger for bicycling. Freezers showed a similar pattern in general. Superimposed on this pattern, however, we observed a movement-induced, narrowband power increase around 18Hz, which was evident even in the absence of freezing. These results indicate that bicycling facilitates overall suppression of beta power. Furthermore, movement leads to exaggerated synchronization in the low beta band specifically within the basal ganglia of patients susceptible to freezing. Abnormal ∼18Hz oscillations are implicated in the pathophysiology of freezing of gait, and suppressing them may form a key strategy in developing potential therapies. Ann Neurol 2017;82:592-601. © 2017 American Neurological Association.
Bracing of the trunk and neck has a differential effect on head control during gait
Russell, D. M.; Kelleran, K.; Walker, M. L.
2015-01-01
During gait, the trunk and neck are believed to play an important role in dissipating the transmission of forces from the ground to the head. This attenuation process is important to ensure head control is maintained. The aim of the present study was to assess the impact of externally restricting the motion of the trunk and/or neck segments on acceleration patterns of the upper body and head and related trunk muscle activity. Twelve healthy adults performed three walking trials on a flat, straight 65-m walkway, under four different bracing conditions: 1) control-no brace; 2) neck-braced; 3) trunk-braced; and 4) neck-trunk braced. Three-dimensional acceleration from the head, neck (C7) and lower trunk (L3) were collected, as was muscle activity from trunk. Results revealed that, when the neck and/or trunk were singularly braced, an overall decrease in the ability of the trunk to attenuate gait-related oscillations was observed, which led to increases in the amplitude of vertical acceleration for all segments. However, when the trunk and neck were braced together, acceleration amplitude across all segments decreased in line with increased attenuation from the neck to the head. Bracing was also reflected by increased activity in erector spinae, decreased abdominal muscle activity and lower trunk muscle coactivation. Overall, it would appear that the neuromuscular system of young, healthy individuals was able to maintain a consistent pattern of head acceleration, irrespective of the level of bracing, and that priority was placed over the control of vertical head accelerations during these gait tasks. PMID:26180113
Relationship between gait initiation and disability in individuals affected by multiple sclerosis.
Galli, Manuela; Coghe, Giancarlo; Sanna, Paola; Cocco, Eleonora; Marrosu, Maria Giovanna; Pau, Massimiliano
2015-11-01
This study analyzes how multiple sclerosis (MS) does affect one of the most common voluntary activities in life: the gait initiation (GI). The main aim of the work is to characterize the execution of this task by measuring and comparing relevant parameters based on center of pressure (COP) patterns and to study the relationship between these and the level of expanded disability status scale (EDSS). To this aim, 95 MS subjects with an average EDSS score of 2.4 and 35 healthy subjects were tested using a force platform during the transition from standing posture to gait. COP time-series were acquired and processed to extract a number of parameters related to the trajectory followed by the COP. The statistical analysis revealed that only a few measurements were statistically different between the two groups and only these were subsequently correlated with EDSS score. The correlation analysis underlined that a progressive alteration of the task execution can be directly related with the increase of EDSS score. These finding suggest that most of the impairment found in people with MS comes from the first part of the COP pattern, the anticipatory postural adjustments (APAs). The central nervous system performs APAs before every voluntary movement to minimize balance perturbation due to the movement itself. Gait Initiation's APAs consist in some ankle muscles contractions that induce a backward COP shift to the swing limb. The analysis here performed highlighted that MS affected patients have a reduced posterior COP shift that reveals that the anticipatory mechanism is impaired. Copyright © 2015 Elsevier B.V. All rights reserved.
Effects of unilateral real-time biofeedback on propulsive forces during gait.
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 targeted limb. These results demonstrate the short-term effects of using unilateral AGRF biofeedback to target propulsion in a specific leg, which may have utility as a training tool for individuals with gait deficits such as post-stroke hemiparesis. Future studies are needed to investigate the effects of real-time AGRF biofeedback as a gait training tool in neurologically-impaired individuals.
Webster, K N; Dawson, T J
2003-09-01
The locomotory characteristics of kangaroos and wallabies are unusual, with both energetic costs and gait parameters differing from those of quadrupedal running mammals. The kangaroos and wallabies have an evolutionary history of only around 5 million years; their closest relatives, the rat-kangaroos, have a fossil record of more than 26 million years. We examined the locomotory characteristics of a rat-kangaroo, Bettongia penicillata. Locomotory energetics and gait parameters were obtained from animals exercising on a motorised treadmill at speeds from 0.6 m s(-1) to 6.2 m s(-1). Aerobic metabolic costs increased as hopping speed increased, but were significantly different from the costs for a running quadruped; at the fastest speed, the cost of hopping was 50% of the cost of running. Therefore B. penicillata can travel much faster than quadrupedal runners at similar levels of aerobic output. The maximum aerobic output of B. penicillata was 17 times its basal metabolism. Increases in speed during hopping were achieved through increases in stride length, with stride frequency remaining constant. We suggest that these unusual locomotory characteristics are a conservative feature among the hopping marsupials, with an evolutionary history of 20-30 million years.
Astephen Wilson, Janie L; Dunbar, Michael J; Hubley-Kozey, Cheryl L
2015-01-01
The future of total knee arthroplasty (TKA) surgery will involve planning that incorporates more patient-specific characteristics. Despite known biological, morphological, and functional differences between men and women, there has been little investigation into knee joint biomechanical and neuromuscular differences between men and women with osteoarthritis, and none that have examined sex-specific biomechanical and neuromuscular responses to TKA surgery. The objective of this study was to examine sex-associated differences in knee kinematics, kinetics and neuromuscular patterns during gait before and after TKA. Fifty-two patients with end-stage knee OA (28 women, 24 men) underwent gait and neuromuscular analysis within the week prior to and one year after surgery. A number of sex-specific differences were identified which suggest a different manifestation of end-stage knee OA between the sexes. Copyright © 2014 Elsevier Inc. All rights reserved.
Jasiewicz, Jan M; Allum, John H J; Middleton, James W; Barriskill, Andrew; Condie, Peter; Purcell, Brendan; Li, Raymond Che Tin
2006-12-01
We report on three different methods of gait event detection (toe-off and heel strike) using miniature linear accelerometers and angular velocity transducers in comparison to using standard pressure-sensitive foot switches. Detection was performed with normal and spinal-cord injured subjects. The detection of end contact (EC), normally toe-off, and initial contact (IC) normally, heel strike was based on either foot linear accelerations or foot sagittal angular velocity or shank sagittal angular velocity. The results showed that all three methods were as accurate as foot switches in estimating times of IC and EC for normal gait patterns. In spinal-cord injured subjects, shank angular velocity was significantly less accurate (p<0.02). We conclude that detection based on foot linear accelerations or foot angular velocity can correctly identify the timing of IC and EC events in both normal and spinal-cord injured subjects.
Adaptive Gait Control for a Quadruped Robot on 3D Path Planning
NASA Astrophysics Data System (ADS)
Igarashi, Hiroshi; Kakikura, Masayoshi
A legged walking robot is able to not only move on irregular terrain but also change its posture. For example, the robot can pass under overhead obstacles by crouching. The purpose of our research is to realize efficient path planning with a quadruped robot. Therefore, the path planning is expected to extended in three dimensions because of the mobility. However, some issues of the quadruped robot, which are instability, workspace limitation, deadlock and slippage, complicate realizing such application. In order to improve these issues and reinforce the mobility, a new static gait pattern for a quadruped robot, called TFG: Trajectory Following Gait, is proposed. The TFG intends to obtain high controllability like a wheel robot. Additionally, the TFG allows to change it posture during the walk. In this paper, some experimental results show that the TFG improves the issues and it is available for efficient locomotion in three dimensional environment.
The predictive value of cerebrospinal fluid tap-test in normal pressure hydrocephalus.
Damasceno, B P; Carelli, E F; Honorato, D C; Facure, J J
1997-06-01
Eighteen patients (mean age of 66.5 years) with normal pressure hydrocephalus (NPH) underwent a ventriculo-peritoneal shunt surgery. Prior to operation a cerebrospinal fluid tap-test (CSF-TT) was performed with measurements of gait pattern and psychometric functions (memory, visuo-motor speed and visuo-constructive skills) before and after the removal of 50 ml CSF by lumbar puncture (LP). Fifteen patients improved and 3 were unchanged after surgery. Short duration of disease, gait disturbance preceding mental deterioration, wide temporal horns and small sulci on CT-scan were associated with good outcome after shunting. There was a good correlation between the results of CSF-TT and shunt surgery (chi 2 = 4.11, phi = 0.48, p < 0.05), with gait test showing highest correlation (r = 0.99, p = 0.01). In conclusion, this version of CSF-TT proved to be an effective test to predict improvement after shunting in patients with NPH.
Six degree-of-freedom knee joint kinematics in obese individuals with knee pain during gait.
Li, Jing-Sheng; Tsai, Tsung-Yuan; Felson, David T; Li, Guoan; Lewis, Cara L
2017-01-01
Knee joint pain is a common symptom in obese individuals and walking is often prescribed as part of management programs. Past studies in obese individuals have focused on standing alignment and kinematics in the sagittal and coronal planes. Investigation of 6 degree-of-freedom (6DOF) knee joint kinematics during standing and gait is important to thoroughly understand knee function in obese individuals with knee pain. This study aimed to investigate the 6DOF knee joint kinematics in standing and during gait in obese patients using a validated fluoroscopic imaging system. Ten individuals with obesity and knee pain were recruited. While standing, the knee was in 7.4±6.3°of hyperextension, 2.8±3.3° of abduction and 5.6±7.3° of external rotation. The femoral center was located 0.7±3.1mm anterior and 5.1±1.5mm medial to the tibial center. During treadmill gait, the sagittal plane motion, i.e., flexion/extension and anterior-posterior translation, showed a clear pattern. Specifically, obese individuals with knee pain maintained the knee in more flexion and more anterior tibial translation during most of the stance phase of the gait cycle and had a reduced total range of knee flexion when compared to a healthy non-obese group. In conclusion, obese individuals with knee pain used hyperextension knee posture while standing, but maintained the knee in more flexion during gait with reduced overall range of motion in the 6DOF analysis.
Six degree-of-freedom knee joint kinematics in obese individuals with knee pain during gait
Li, Jing-Sheng; Tsai, Tsung-Yuan; Felson, David T.; Li, Guoan; Lewis, Cara L.
2017-01-01
Knee joint pain is a common symptom in obese individuals and walking is often prescribed as part of management programs. Past studies in obese individuals have focused on standing alignment and kinematics in the sagittal and coronal planes. Investigation of 6 degree-of-freedom (6DOF) knee joint kinematics during standing and gait is important to thoroughly understand knee function in obese individuals with knee pain. This study aimed to investigate the 6DOF knee joint kinematics in standing and during gait in obese patients using a validated fluoroscopic imaging system. Ten individuals with obesity and knee pain were recruited. While standing, the knee was in 7.4±6.3°of hyperextension, 2.8±3.3° of abduction and 5.6±7.3° of external rotation. The femoral center was located 0.7±3.1mm anterior and 5.1±1.5mm medial to the tibial center. During treadmill gait, the sagittal plane motion, i.e., flexion/extension and anterior-posterior translation, showed a clear pattern. Specifically, obese individuals with knee pain maintained the knee in more flexion and more anterior tibial translation during most of the stance phase of the gait cycle and had a reduced total range of knee flexion when compared to a healthy non-obese group. In conclusion, obese individuals with knee pain used hyperextension knee posture while standing, but maintained the knee in more flexion during gait with reduced overall range of motion in the 6DOF analysis. PMID:28339477
Dynamic parameters of three-point crutch gait in female patients after total hip arthroplasty.
Murawa, Michał; Dworak, Lechosław B; Kabaciński, Jarosław; Syczewska, Małgorzata; Rzepnicka, Agata
2016-01-01
Patient recovery after a surgical procedure depends, among other factors, on the amount of the body weight with which patient loads lower limb. Research studies report different results of the degree of body weight with which lower limb is loaded during three-point crutch gait. The aim of this study was to evaluate the level of the ground reaction forces (GRF) during crutch gait used by patients after total hip arthroplasty (THA) in the first week after discharge from the orthopaedic units. Ten female patients diagnosed with primary unilateral coxarthrosis participated in a single measurement session. In order to record kinematic and dynamic variables of this gait pattern motion analysis system was used together with two force plates. The static test of body weight distribution between lower limbs was performed on a dual-top stabilometric plate. The average peak values of loading on the operated (O) limb during mid stance and terminal stance of three-point crutch gait were 64.6% and 64.3% of body weight (BW), respectively, whereas in the case of the nonoperated (NO) limb 103.5%BW and 108.8%BW, respectively. The maximum loads on the crutches were significantly higher (by 9%BW) on the NO side as compared to the O side ( p < 0.05). During the static test, average values of body weight distribution on the O and NO limb were 36%BW and 64%BW, respectively. The patients showed surprisingly similar level of loading on the O limb. The weight bearing on the O limb was lower during static trial than during three-point crutch gait.
Richard, Aliénor; Van Hamme, Angèle; Drevelle, Xavier; Golmard, Jean-Louis; Meunier, Sabine; Welter, Marie-Laure
2017-09-01
Several brain structures including the brainstem, the cerebellum and the frontal cortico-basal ganglia network, with the primary and premotor areas have been shown to participate in the functional organization of gait initiation and postural control in humans, but their respective roles remain poorly understood. The aim of this study was to better understand the role of the supplementary motor area (SMA) and posterior cerebellum in the gait initiation process. Gait initiation parameters were recorded in 22 controls both before and after continuous theta burst transcranial stimulation (cTBS) of the SMA and cerebellum, and were compared to sham stimulation, using a randomized double-blind design study. The two phases of gait initiation process were analyzed: anticipatory postural adjustments (APAs) and execution, with recordings of soleus and tibialis anterior muscles. Functional inhibition of the SMA led to a shortened APA phase duration with advanced and increased muscle activity; during execution, it also advanced muscle co-activation and decreased the duration of stance soleus activity. Cerebellar functional inhibition did not influence the APA phase duration and amplitude but increased muscle co-activation, it decreased execution duration and showed a trend to increase velocity, with increased swing soleus muscle duration and activity. The results suggest that the SMA contributes to both the timing and amplitude of the APAs with no influence on step execution and the posterior cerebellum in the coupling between the APAs and execution phases and leg muscle activity pattern during gait initiation. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.
Sosdian, L; Dobson, F; Wrigley, T V; Paterson, K; Bennell, K; Dowsey, M; Choong, P; Allison, K; Hinman, R S
2014-12-01
Knee arthroplasty (KA) is recognized as an effective treatment of knee joint osteoarthritis and up to 90% of patients experience substantial pain relief. There has been no systematic review synthesizing the longitudinal changes in gait following KA. The aims of this systematic review were to determine the effects of KA on (i) frontal plane and (ii) sagittal plane kinematic and kinetic parameters during the stance phase of gait. MEDLINE (PubMed), CINAHL, SPORTdiscus (EBSCO), and Cochrane Library (Wiley) were searched until April 10th, 2014. 1,765 articles were identified, of which 19 studies describing 3-dimensional gait analysis pre- and post-KA were included. Study quality was evaluated by two reviewers independently using the Downs and Black checklist. Following KA, in the frontal plane, the maximum knee adduction angle and external knee adduction moment (KAM) tended to decrease. In the sagittal plane, findings suggest that the maximum knee flexion moment is increased. From the ten studies that included a healthy reference group, it was unclear whether gait variables returned to normal following KA. Overall, it appears that KA results in a decreased peak KAM and maximum knee adduction angles, an increased peak knee flexion moment and inconsistent changes in the peak knee flexion angle. Knowledge gaps remain due to methodological inconsistencies across studies, limited statistical analysis, and largely heterogeneous sample populations. More research is needed to determine whether KA restores gait patterns to normal, or if additional rehabilitation may be needed to optimize gait following surgery for osteoarthritis. Copyright © 2014 Elsevier B.V. All rights reserved.
Moon, Hyun Im; Pyun, Sung-Bom; Tae, Woo-Suk; Kwon, Hee Kyu
2016-07-01
Stroke impairs motor, balance, and gait function and influences activities of daily living. Understanding the relationship between brain lesions and deficits can help clinicians set goals during rehabilitation. We sought to elucidate the neural substrates of lower extremity motor, balance, and ambulation function using voxel-based lesion symptom mapping (VLSM) in supratentorial stroke patients. We retrospectively screened patients who met the following criteria: first-ever stroke, supratentorial lesion, and available brain magnetic resonance imaging (MRI) data. MRIs of 133 stroke patients were selected for VLSM analysis. We generated statistical maps of lesions related to lower extremity motor (lower extremity Fugl-Meyer assessment, LEFM), balance (Berg Balance Scale, BBS), and gait (Functional Ambulation Category, FAC) using VLSM. VLSM revealed that lower LEFM scores were associated with damage to the bilateral basal ganglia, insula, internal capsule, and subgyral white matter adjacent to the corona radiata. The lesions were more widely distributed in the left than in the right hemisphere, representing motor and praxis function necessary for performing tasks. However, no associations between lesion maps and balance and gait function were established. Motor impairment of the lower extremities was associated with lesions in the basal ganglia, insula, internal capsule, and white matter adjacent to the corona radiata. However, VLSM revealed no specific lesion locations with regard to balance and gait function. This might be because balance and gait are complex skills that require spatial and temporal integration of sensory input and execution of movement patterns. For more accurate prediction, factors other than lesion location need to be investigated.
Arm swing magnitude and asymmetry during gait in the early stages of Parkinson's disease.
Lewek, Michael D; Poole, Roxanne; Johnson, Julia; Halawa, Omar; Huang, Xuemei
2010-02-01
The later stages of Parkinson's disease (PD) are characterized by altered gait patterns. Although decreased arm swing during gait is the most frequently reported motor dysfunction in individuals with PD, quantitative descriptions of gait in early PD have largely ignored upper extremity movements. This study was designed to perform a quantitative analysis of arm swing magnitude and asymmetry that might be useful in the assessment of early PD. Twelve individuals with early PD (in "off" state) and eight controls underwent gait analysis using an optically-based motion capture system. Participants were instructed to walk at normal and fast velocities, and then on heels (to minimize push-off). Arm swing was measured as the excursion of the wrist with respect to the pelvis. Arm swing magnitude for each arm, and inter-arm asymmetry, were compared between groups. Both groups had comparable gait velocities (p = 0.61), and there was no significant difference between the groups in the magnitude of arm swing in all walking conditions for the arm that swung more (p = 0.907) or less (p = 0.080). Strikingly, the PD group showed significantly greater arm swing asymmetry (asymmetry angle: 13.9 + or - 7.9%) compared to the control group (asymmetry angle: 5.1 + or - 4.0%; p = 0.003). Unlike arm swing magnitude, arm swing asymmetry unequivocally differs between people with early PD and controls. Such quantitative evaluation of arm swing, especially its asymmetry, may have utility for early and differential diagnosis, and for tracking disease progression in patients with later PD. Copyright 2009 Elsevier B.V. All rights reserved.
Arm Swing Magnitude and Asymmetry During Gait in the Early Stages of Parkinson's Disease
Lewek, Michael D.; Poole, Roxanne; Johnson, Julia; Halawa, Omar; Huang, Xuemei
2009-01-01
The later stages of Parkinson's disease (PD) are characterized by altered gait patterns. Although decreased arm swing during gait is the most frequently reported motor dysfunction in individuals with PD, quantitative descriptions of gait in early PD have largely ignored upper extremity movements. This study was designed to perform a quantitative analysis of arm swing magnitude and asymmetry that might be useful in the assessment of early PD. Twelve individuals with early PD (in “off” state) and eight controls underwent gait analysis using an optically-based motion capture system. Participants were instructed to walk at normal and fast velocities, and then on heels (to minimize push-off). Arm swing was measured as the excursion of the wrist with respect to the pelvis. Arm swing magnitude for each arm, and inter-arm asymmetry, were compared between groups. Both groups had comparable gait velocities (p=0.61), and there was no significant difference between the groups in the magnitude of arm swing in all walking conditions for the arm that swung more (p=0.907) or less (p=0.080). Strikingly, the PD group showed significantly greater arm swing asymmetry (asymmetry angle: 13.9±7.9%) compared to the control group (asymmetry angle: 5.1±4.0%; p=0.003). Unlike arm swing magnitude, arm swing asymmetry unequivocally differs between people with early PD and controls. Such quantitative evaluation of arm swing, especially its asymmetry, may have utility for early and differential diagnosis, and for tracking disease progression in patients with later PD. PMID:19945285
Effect of observation on lower limb prosthesis gait biomechanics: Preliminary results.
Malchow, Connor; Fiedler, Goeran
2016-12-01
The Hawthorne effect, a subcategory of reactivity, causes human behavior to change when under observation. Such an effect may apply to gait variation of persons with prosthetics or orthotics devices. This study investigated whether the presence of observers directly affects the gait pattern of users of lower limb prostheses. Within-subject intervention study. Primary outcome measures were gait parameters of initial double support time and upper body lateral tilt angle, which were collected with a mobile sensor attached to the subjects' back. To make subjects feel unwatched, a certain amount of deception was necessary, and two different conditions were created and statistically compared against each other: one in which the subjects were initially unaware of the attention of observers and another one in which the same subjects were aware of a group of observers. Data from two subjects using trans-femoral prosthesis are reported. Findings included a change in step initial double support percentage by up to 14.2% (p = 0.019). Considerable changes were also noted in secondary outcome measures including speed, stride length, and stride symmetry. A reactivity effect of observation exists in prosthetics gait analysis. More comprehensive studies may be motivated by these preliminary findings. Results of this study suggest that users of lower limb prostheses walk differently when their gait is being assessed (e.g. in the prosthetist's office) than in situations without observers. This may in part explain the clinical experience that modifications of prosthetic fit or alignment provide only short-term betterment. © The International Society for Prosthetics and Orthotics 2015.
Moreno Catalá, María; Woitalla, Dirk; Arampatzis, Adamantios
2016-07-01
Gait and balance disorders are common in Parkinson's disease (PD) and major contributors to increased falling risk. Predictive and reactive adjustments can improve recovery performance after gait perturbations. However, these mechanisms have not been investigated in young-onset PD. We aimed to investigate the effect of gait perturbations on dynamic stability control as well as predictive and reactive adaptability to repeated gait perturbations in young PD patients. Fifteen healthy controls and twenty-five young patients (48±5yrs.) walked on a walkway. By means of a covered exchangeable element, the floor surface condition was altered to induce gait perturbations. The experimental protocol included a baseline on a hard surface, an unexpected trial on a soft surface and an adaptation phase with 5 soft trials to quantify the reactive adaptation. After the first and sixth soft trials, the surface was changed to hard, to examine after-effects and, thus, predictive motor control. Dynamic stability was assessed using the 'extrapolated center of mass' concept. Patients' unperturbed walking was less stable than controls' and this persisted in the perturbed trials. Both groups demonstrated after-effects directly after the first perturbation, showing similar predictive responses. However, PD patients did not improve their reactive behavior after repeated perturbations while controls showed clear locomotor adaptation. Our data suggest that more unstable gait patterns and a less effective reactive adaptation to perturbed walking may be a disease-related characteristic in young PD patients. These deficits were related to reduced ability to increase the base of support. Copyright © 2016 Elsevier B.V. All rights reserved.
Moore, Talia Y; Cooper, Kimberly L; Biewener, Andrew A; Vasudevan, Ramanarayan
2017-09-05
Mechanistically linking movement behaviors and ecology is key to understanding the adaptive evolution of locomotion. Predator evasion, a behavior that enhances fitness, may depend upon short bursts or complex patterns of locomotion. However, such movements are poorly characterized by existing biomechanical metrics. We present methods based on the entropy measure of randomness from Information Theory to quantitatively characterize the unpredictability of non-steady-state locomotion. We then apply the method by examining sympatric rodent species whose escape trajectories differ in dimensionality. Unlike the speed-regulated gait use of cursorial animals to enhance locomotor economy, bipedal jerboa (family Dipodidae) gait transitions likely enhance maneuverability. In field-based observations, jerboa trajectories are significantly less predictable than those of quadrupedal rodents, likely increasing predator evasion ability. Consistent with this hypothesis, jerboas exhibit lower anxiety in open fields than quadrupedal rodents, a behavior that varies inversely with predator evasion ability. Our unpredictability metric expands the scope of quantitative biomechanical studies to include non-steady-state locomotion in a variety of evolutionary and ecologically significant contexts.Biomechanical understanding of animal gait and maneuverability has primarily been limited to species with more predictable, steady-state movement patterns. Here, the authors develop a method to quantify movement predictability, and apply the method to study escape-related movement in several species of desert rodents.
Rupp, Rüdiger; Plewa, Harry; Schuld, Christian; Gerner, Hans Jürgen; Hofer, Eberhard P; Knestel, Markus
2011-02-01
In incomplete spinal cord injured subjects, task-oriented training regimes are applied for enhancement of neuroplasticity to improve gait capacity. However, a sufficient training intensity can only be achieved during the inpatient phase, which is getting shorter and shorter due to economic restrictions. In the clinical environment, complex and expensive robotic devices have been introduced to maintain the duration and the intensity of the training, but up to now only a few exist for continuation of automated locomotion training at home. For continuation of the automated locomotion training at home prototypes of the compact, pneumatically driven orthosis MoreGait have been realized, which generate the key afferent stimuli for activation of the spinal gait pattern generator. Artificial pneumatic muscles with excellent weight-to-force ratio and safety characteristics have been integrated as joint actuators. Additionally, a Stimulative Shoe for generation of the appropriate foot loading pattern has been developed without the need for verticalization of the user. The first results of the pilot study in eight chronic incomplete spinal cord injured subjects indicate that the home-based therapy is safe and feasible. The therapy related improvements of the walking capacity are in the range of locomotion robots used in clinical settings.
Meijer, Onno G.
2016-01-01
Introduction Patients with chronic low back pain (CLBP) often demonstrate altered timing of thorax rotations in the transverse plane during gait. Increased axial trunk stiffness has been claimed to cause this movement pattern. Objectives The objective of this study was to assess whether axial trunk stiffness is increased in gait in CLBP patients. Methods 15 CLBP patients and 15 healthy controls walked on a treadmill that imposed rotational perturbations in the transverse plane. The effect of these perturbations on transverse pelvis, thorax and trunk (thorax relative to pelvis) rotations was evaluated in terms of residual rotations, i.e., the deviation of these movements from the unperturbed patterns. In view of the heterogeneity of the CLBP group, we additionally performed a subgroup comparison between seven patients and seven controls with maximal between-group contrast for timing of thorax rotations. Results Rotations of the walking surface had a clear effect on transverse pelvis, thorax and trunk rotations in all groups. No significant between-group differences on residual transverse pelvis, thorax and trunk rotations were observed. Conclusion Axial trunk stiffness in gait does not appear to be increased in CLBP. Altered timing of thorax rotations in CLBP does not seem to be a result of increased axial trunk stiffness. PMID:27310528
Behavioural effects of prenatal exposure to carbon disulphide and to aromatol in rats.
Lehotzky, K; Szeberényi, J M; Ungváry, G; Kiss, A
1985-01-01
The neurotoxic effects of prenatal organosolvent inhalation were studied in rats, because of the expectation that a developing organism may be more sensitive than the adult to the induction of functional deficits. The aim was to determine whether prenatal exposure to the new organosolvent mixture, Aromatol, and the well known neurotoxic carbon disulphide, would impair reflex ontogeny or produce neurobehavioural dysfunctions in the offspring. Development of gait, motor coordination, and activity, avoidance learning and swimming were tested in the offspring of CFY rat mothers, exposed to CS2 inhalation (0, less than 10, 700 and 2000 mg/m3) and to Aromatol (0, 600, 1000 and 2000 mg/m3) on days 7-15 gestation. Prenatal CS2 inhalation induced dose related perinatal mortality of pups. Eye opening and the auditory startle were retarded. There were immature gait, motor incoordination, diminished open field activity and altered behavioural patterns on day 21 and 36 but they were nearly age-appropriate on day 90. As signs of disturbed learning ability, there were diminished performance and lengthened latency of the conditioned avoidance response, related to the concentrations administered. Contrary to expectations, prenatal Aromatol inhalation had no effect on maturation of gait, behaviour patterns, or learning ability.
Thijssen, Dick H; Paulus, Rebecca; van Uden, Caro J; Kooloos, Jan G; Hopman, Maria T
2007-02-01
To measure energy cost and gait analysis in persons with stroke with and without a newly developed orthosis. Immediate and long-term (3wk) intervention (before-after trial). University medical center. Volunteer sample of 27 persons with long-term (range, 0.6-19y) hemiparetic stroke. Three-week familiarization to the new walking aid. Energy cost (per distance walked), preferred walking speed (PWS), and step length. Energy cost was examined in all subjects while walking on a treadmill at 3 different velocities (PWS, PWS+30%, PWS-30%) during 3 different situations (without orthosis, with orthosis, after 3-wk orthosis familiarization). Spatiotemporal aspects of the gait pattern were examined using a 6-m instrumented walkway system. Using the orthosis immediately decreased energy cost in persons with stroke during walking at the PWS (P<.001) and significantly increased walking speed (P<.005) and step length (P<.001). After 3 weeks of familiarization to the orthosis, energy cost at the PWS and at PWS+30% showed further improvement in energy cost (P<.05). The newly developed orthosis immediately decreases energy cost and improves walking speed and step length in persons with long-term stroke. After only 3 weeks of orthosis familiarization, energy cost shows additional improvement.
First published record of urban malaria in Puerto Gaitán, Meta, Colombia
Buitrago, Luz Stella; Brochero, Helena Luisa; McKeon, Sascha N; Lainhart, William; Conn, Jan E
2013-01-01
Patterns of malaria cases were compared between the department of Meta and the municipality of Puerto Gaitán, Colombia, to examine temporal change in malaria from 2005-2010. During this time frame in Meta the mean ratio was 2.53; in contrast, in Puerto Gaitán it was 1.41, meaning that a surprisingly high proportion of Plasmodium falciparum cases were reported from this municipality. A detailed analysis of data from Puerto Gaitán for 2009 and 2010 detected a significant difference (χ2, p < 0.001) in the distribution of plasmodia, with Plasmodium vivax more prevalent in 2009 and P. falciparum in 2010. Males had the highest number of cases but there was no difference in the distribution of cases between sexes and years. In both years, for both sexes, people 16-40 accounted for the majority of cases (58.9% in 2009; 60.4% in 2010). There were significant differences in the distribution of both P. vivax (χ2, p < 0.01) and P. falciparum cases (χ2, p < 0.05) by geographic setting (urban vs. non-urban) between years. Urban cases of both P. vivax and P. falciparum are recorded in this study for the first time in Puerto Gaitán, possibly the result of area wide displacement and migration due to armed conflict. PMID:24402157
Mao, Yurong; Chen, Peiming; Li, Lifang; Li, Le; Huang, Dongfeng
2015-01-01
Gait recovery is very important to stroke survivors to regain their independence in activity of daily life. This study aimed to investigate the effects of virtual reality (VR) coupled body weight support treadmill training (BWSTT) on pelvic control at the early stage of stroke. Kinematic and kinetic changes of pelvic motion were evaluated by a 3D gait analysis system and were compared to the results from over-ground walking training. Twenty-four patients having unilateral hemiplegia with subacute stroke were recruited to a VR coupled BWSTT group (n= 12) and a conventional therapy (CT) group (n= 12). Both of the groups received training of 20-40 min/day, 5 days/week, for 3 weeks. The results showed the tilt of pelvis in sagittal plane improved significantly (P= 0.038) after treatment in the BWSTT+VR group, in terms of decreased amplitude of anterior peak (mean, from 10.99° to 6.25°), while there were no significant differences in the control group. The findings suggested that VR coupled BWSTT gait training could decrease anterior tilt of pelvis in early hemiparetic persons following a modest intervention dose, and the training may have advantages over conventional over-ground gait training and can assist the therapists in correcting abnormal gait pattern of stroke survivors.
Advantages of EEG phase patterns for the detection of gait intention in healthy and stroke subjects
NASA Astrophysics Data System (ADS)
Ioana Sburlea, Andreea; Montesano, Luis; Minguez, Javier
2017-06-01
Objective. One use of EEG-based brain-computer interfaces (BCIs) in rehabilitation is the detection of movement intention. In this paper we investigate for the first time the instantaneous phase of movement related cortical potential (MRCP) and its application to the detection of gait intention. Approach. We demonstrate the utility of MRCP phase in two independent datasets, in which 10 healthy subjects and 9 chronic stroke patients executed a self-initiated gait task in three sessions. Phase features were compared to more conventional amplitude and power features. Main results. The neurophysiology analysis showed that phase features have higher signal-to-noise ratio than the other features. Also, BCI detectors of gait intention based on phase, amplitude, and their combination were evaluated under three conditions: session-specific calibration, intersession transfer, and intersubject transfer. Results show that the phase based detector is the most accurate for session-specific calibration (movement intention was correctly detected in 66.5% of trials in healthy subjects, and in 63.3% in stroke patients). However, in intersession and intersubject transfer, the detector that combines amplitude and phase features is the most accurate one and the only that retains its accuracy (62.5% in healthy subjects and 59% in stroke patients) w.r.t. session-specific calibration. Significance. MRCP phase features improve the detection of gait intention and could be used in practice to remove time-consuming BCI recalibration.
Reshaping of Gait Coordination by Robotic Intervention in Myelopathy Patients After Surgery
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