Dissertations / Theses: 'Stance phase of gait'

1

Aoki(Sakuma), Kaoru. "Immediate effects of stance and swing phase training on gait in patients with stroke." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/265169.

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京都大学
新制・論文博士
博士(人間健康科学)
乙第13430号
論人健博第8号
新制||人健||6(附属図書館)
京都大学大学院医学研究科人間健康科学系専攻
(主査)教授黒木裕士, 教授青山朋樹, 教授松田秀一
学位規則第4条第2項該当
Doctor of Human Health Sciences
Kyoto University
DFAM

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Wangerin, Spencer D. "Development and validation of a human knee joint finite element model for tissue stress and strain predictions during exercise." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/1129.

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Osteoarthritis (OA) is a degenerative condition of cartilage and is the leading cost of disability in the United States. Motion analysis experiments in combination with knee-joint finite element (FE) analysis may be used to identify exercises that maintain knee-joint osteochondral (OC) loading at safe levels for patients at high-risk for knee OA, individuals with modest OC defects, or patients rehabilitating after surgical interventions. Therefore, a detailed total knee-joint FE model was developed by modifying open-source knee-joint geometries in order to predict OC tissue stress and strain during the stance phase of gait. The model was partially validated for predicting the timing and locations of maximum contact parameters (contact pressure, contact area, and principal Green-Lagrangian strain), but over-estimated contact parameters compared with both published in vivo studies and other FE analyses of the stance phase of gait. This suggests that the model geometry and kinematic boundary conditions utilized in this FE model are appropriate, but limitations in the material properties used, as well as potentially the loading boundary conditions represent primary areas for improvement.

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3

Dalton, Elan. "Influence of initial stance configuration on gait initiation." [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0041274.

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4

Wühr, Max. "Sensorimotor postural control in healthy and pathological stance and gait." Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-178182.

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Postural control during standing and walking is an inherently unstable task requiring the interaction of various biomechanical, sensory, and neurophysiological mechanisms to shape stable patterns of whole-body coordination that are able to counteract postural disequilibrium. This thesis focused on the examination of central aspects of the functional roles of these mechanisms and the modes of interaction between them. A further aim was to determine the conditions of dynamic stability for healthy standing and walking performance as well as for certain balance and gait disorders. By studying movement fluctuations in the walking pattern it could be demonstrated that dynamic stability during walking depends on gait speed and is differentially regulated for the medio-lateral and the fore-aft walking planes. Stability control in the fore-aft walking plane exhibits attractor dynamics typical for a dynamical system. Accordingly, the most stable pattern of movement coordination in terms of minimal fluctuations in the order parameter (i.e., the relative phase between the two oscillating legs) can be observed at the attractor of self-paced walking. Critical fluctuations occur at increasingly non-preferred speeds, indicating a loss of dynamic gait stability close to the speed boundaries of the walking mode. Moreover, stability control during slow walking is critically dependent on sensory feedback control, whereas dynamic stability during fast walking relies mainly on the smooth operation of cerebellar pacemaker regions. Disturbances of sensory and cerebellar locomotor control in certain gait disorders could be further linked to a loss of dynamic gait stability, in particular an increased risk of falls. Furthermore, this thesis examined alterations in the sensorimotor postural control scheme that may trigger the experience of subjective imbalance and vertigo in the conditions of phobic postural vertigo and visual height intolerance. Both conditions are characterized by an inadequate mode of balance regulation featuring increased levels of open-loop balance control and a precipitate integration of closed-loop sensory feedback into the postural control scheme. This inadequate balance control strategy is accompanied by a stiffening of the anti-gravity musculature and is elicited by specific influences of attention and sensory feedback control. The findings of this thesis contribute to the understanding of central sensorimotor mechanisms involved in the control of dynamic postural stability during standing and walking. They further provide relevant information for the differential diagnosis and fall risk estimation of certain balance and gait disorders.

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Massenzo, Trisha J. "An Investigation of Kinetic Visual Biofeedback on Dynamic Stance Symmetry." VCU Scholars Compass, 2016. http://scholarscompass.vcu.edu/etd/4661.

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The intent of the following research is to utilize task-specific, constraint-induced therapies and apply towards dynamic training for symmetrical balance. Modifications to an elliptical trainer were made to both measure weight distributions during dynamic stance as well as provide kinetic biofeedback through a man-machine interface. Following a review of the background, which includes research from several decades that are seminal to current studies, a design review is discussed to cover the design of the modified elliptical (Chapter 2). An initial study was conducted in a healthy sample population in order to determine the best visual biofeedback representation by comparing different man-machine interfaces (Chapter 3). Index of gait symmetry measures indicated that one display interface optimized participant performance during activity with the modified elliptical trainer. A second study was designed to determine the effects of manipulating the gain of the signal to encourage increased distribution towards the non-dominant weight bearing limb. The purpose of the second study was to better understand the threshold value of gain manipulation in a healthy sample set. Results analyzing percentage error as a measure of performance show that a range between 5-10% allows for a suitable threshold value to be applied for participants who have suffered a stroke. A final study was conducted to apply results/knowledge from the previous two studies to a stroke cohort to determine short-term carryover following training with the modified elliptical trainer. Data taken from force measurements on the elliptical trainer suggest that there was carryover with decreased error from pre to post training. For one participant GaitRite® data show a significant difference from pre to post measurements in single limb support. The results of the research suggest that visual biofeedback can improve symmetrical performance during dynamic patterns. For a better understanding of visual biofeedback delivery, one display representation proved to be beneficial compared to the others which resulted in improved performance. Results show that healthy human participants can minimize error with visual biofeedback and continue minimizing error until a threshold value of 10%. Finally, results have shown promise towards applying such a system for kinetic gait rehabilitation.

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Sparrow, Leah M., Emily Pellatt, Sabrina S. Yu, David A. Raichlen, Herman Pontzer, and Campbell Rolian. "Gait changes in a line of mice artificially selected for longer limbs." PEERJ INC, 2017. http://hdl.handle.net/10150/623229.

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In legged terrestrial locomotion, the duration of stance phase, i.e., when limbs are in contact with the substrate, is positively correlated with limb length, and negatively correlated with the metabolic cost of transport. These relationships are well documented at the interspecific level, across a broad range of body sizes and travel speeds. However, such relationships are harder to evaluate within species (i.e., where natural selection operates), largely for practical reasons, including low population variance in limb length, and the presence of confounding factors such as body mass, or training. Here, we compared spatiotemporal kinematics of gait in Longshanks, a long-legged mouse line created through artificial selection, and in random-bred, mass-matched Control mice raised under identical conditions. We used a gait treadmill to test the hypothesis that Longshanks have longer stance phases and stride lengths, and decreased stride frequencies in both fore- and hind limbs, compared with Controls. Our results indicate that gait differs significantly between the two groups. Specifically, and as hypothesized, stance duration and stride length are 8–10% greater in Longshanks, while stride frequency is 8% lower than in Controls. However, there was no difference in the touch-down timing and sequence of the paws between the two lines. Taken together, these data suggest that, for a given speed, Longshanks mice take significantly fewer, longer steps to cover the same distance or running time compared to Controls, with important implications for other measures of variation among individuals in whole-organism performance, such as the metabolic cost of transport.

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Wühr, Max [Verfasser], and Hans [Akademischer Betreuer] Straka. "Sensorimotor postural control in healthy and pathological stance and gait / Max Wühr. Betreuer: Hans Straka." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2014. http://d-nb.info/1066206457/34.

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8

Liu, Zongyi. "Gait-Based Recognition at a Distance: Performance, Covariate Impact and Solutions." Scholar Commons, 2004. https://scholarcommons.usf.edu/etd/1134.

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It has been noticed for a long time that humans can identify others based on their biological movement from a distance. However, it is only recently that computer vision based gait biometrics has received much attention. In this dissertation, we perform a thorough study of gait recognition from a computer vision perspective. We first present a parameterless baseline recognition algorithm, which bases similarity on spatio-temporal correlation that emphasizes gait dynamics as well as gait shapes. Our experiments are performed with three popular gait databases: the USF/NIST HumanID Gait Challenge outdoor database with 122 subjects, the UMD outdoor database with 55 subjects, and the CMU Mobo indoor database with 25 subjects. Despite its simplicity, the baseline algorithm shows strong recognition power. On the other hand, the outcome suggests that changes in surface and time have strong impact on recognition with significant drop in performance. To gain insight into the effects of image segmentation on recognition -- a possible cause for performance degradation, we propose a silhouette reconstruction method based on a Population Hidden Markov Model (pHMM), which models gait over one cycle, coupled with an Eigen-stance model utilizing the Principle Component Analysis (PCA) of the silhouette shapes. Both models are built from a set of manually created silhouettes of 71 subjects. Given a sequence of machine segmented silhouettes, each frame is matched into a stance by pHMM using the Viterbi algorithm, and then is projected into and reconstructed by the Eigen-stance model. We demonstrate that the system dramatically improves the silhouette quality. Nonetheless, it does little help for recognition, indicating that segmentation is not the key factor of the covariate impacts. To improve performance, we look into other aspects. Toward this end, we propose three recognition algorithms: (i) an averaged silhouette based algorithm that deemphasizes gait dynamics, which substantially reduces computation time but achieves similar recognition power with the baseline algorithm; (ii) an algorithm that normalizes gait dynamics using pHMM and then uses Euclidean distance between corresponding selected stances -- this improves recognition over surface and time; and (iii) an algorithm that also performs gait dynamics normalization using pHMM, but instead of Euclidean distances, we consider distances in shape space based on the Linear Discriminant Analysis (LDA) and consider measures that are invariant to morphological deformation of silhouettes. This algorithm statistically improves the recognition over all covariates. Compared with the best reported algorithm to date, it improves the top-rank identification rate (gallery size: 122 subjects) for comparison across hard covariates: briefcase, surface type and time, by 22%, 14%, and 12% respectively. In addition to better gait algorithms, we also study multi-biometrics combination to improve outdoor biometric performance, specifically, fusing with face data. We choose outdoor face recognition, a "known" hard problem in face biometrics, and test four combination schemes: score sum, Bayesian rule, confidence score sum, and rank sum. We find that the recognition power after combination is significantly stronger although individual biometrics are weak, suggesting another effective approach to improve biometric recognition. The fundamental contributions of this work include (i) establishing the "hard" problems for gait recognition involving comparison across time, surface, and briefcase carrying conditions, (ii) revealing that their impacts cannot be explained by silhouette segmentation, (iii) demonstrating that gait shape is more important than gait dynamics in recognition, and (iv) proposing a novel gait algorithm that outperforms other gait algorithms to date.

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Thota, Anil Kumar. "NEUROMECHANICAL CONTROL OF LOCOMOTION IN INTACT AND INCOMPLETE SPINAL CORD INJURED RATS." UKnowledge, 2004. http://uknowledge.uky.edu/gradschool_theses/195.

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Rodent models are being extensively used to investigate the effects of traumatic injuryand to develop and assess the mechanisms of repair and regeneration. We presentquantitative assessment of 2D kinematics of overground walking and for the first time3D joint angle kinematics of all four limbs during treadmill walking in the intact and inincomplete spinal cord contusion injured (iSCI) adult female Long Evans rats. Phaserelationship between joint angles on a cycle-by-cycle basis and interlimb footfalls areassessed using a simple technique. Electromyogram (EMG) data from major flexor andextensor muscles for each of the hindlimb joints and elbow extensor muscles of theforelimbs synchronized to the 3D kinematics is also obtained in intact rats. EMG activityindicates specific relationships of the neural activity to joint angle kinematics. We findthat the ankle flexors as well as the hip and elbow extensors maintain constant burstduration with changing cycle duration. Overground walking kinematics providesinformation on stance width (SW), stride length (SL) and hindfoot rotation (Rot). SW andRot increased in iSCI rats. Treadmill walking kinematics provides information on jointangle trajectories. In iSCI rats double burst pattern in ankle angle as seen in intact ratsis lost and knee extension and range are reduced. Intra and interlimb coordination isimpaired. Left-right interlimb coordination and forelimb kinematics are not alteredsignificantly. In iSCI rats, maximum flexion of the knee during swing occurs in phasewith the hip as opposed to knee flexion preceeding hip flexion in intact rats. A mildexercise regimen in intact rats over eight weeks does not alter the kinematics.

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10

Hong, Jie. "Human gait identification and analysis." Thesis, Brunel University, 2012. http://bura.brunel.ac.uk/handle/2438/7115.

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Human gait identification has become an active area of research due to increased security requirements. Human gait identification is a potential new tool for identifying individuals beyond traditional methods. The emergence of motion capture techniques provided a chance of high accuracy in identification because completely recorded gait information can be recorded compared with security cameras. The aim of this research was to build a practical method of gait identification and investigate the individual characteristics of gait. For this purpose, a gait identification approach was proposed, identification results were compared by different methods, and several studies about the individual characteristics of gait were performed. This research included the following: (1) a novel, effective set of gait features were proposed; (2) gait signatures were extracted by three different methods: statistical method, principal component analysis, and Fourier expansion method; (3) gait identification results were compared by these different methods; (4) two indicators were proposed to evaluate gait features for identification; (5) novel and clear definitions of gait phases and gait cycle were proposed; (6) gait features were investigated by gait phases; (7) principal component analysis and the fixing root method were used to elucidate which features were used to represent gait and why; (8) gait similarity was investigated; (9) gait attractiveness was investigated. This research proposed an efficient framework for identifying individuals from gait via a novel feature set based on 3D motion capture data. A novel evaluating method of gait signatures for identification was proposed. Three different gait signature extraction methods were applied and compared. The average identification rate was over 93%, with the best result close to 100%. This research also proposed a novel dividing method of gait phases, and the different appearances of gait features in eight gait phases were investigated. This research identified the similarities and asymmetric appearances between left body movement and right body movement in gait based on the proposed gait phase dividing method. This research also initiated an analysing method for gait features extraction by the fixing root method. A prediction model of gait attractiveness was built with reasonable accuracy by principal component analysis and linear regression of natural logarithm of parameters. A systematic relationship was observed between the motions of individual markers and the attractiveness ratings. The lower legs and feet were extracted as features of attractiveness by the fixing root method. As an extension of gait research, human seated motion was also investigated.

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11

During, Alastair B. "An Attempt to Improve Stance Mechanics of Trans-Tibial Amputee Gait by the Design of a Modular Ankle Joint Prosthetic." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29626.

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Background: A-priori research shows that trans-tibial (TT) amputees display poor gait parameters when walking with low-cost ankle-foot prosthetics (here referred to as baseline AFP’s). This has drastic implications for the amputee populations in the developing world specifically, as they have limited access to advanced prosthetic technologies. Low-cost AFP’s are unable to adequately replicate natural stance mechanics, and reliance on these devices results in increased energy expenditure, osteoarthritis and lower-limb joint deterioration. Methodology: This project details the design of a novel ankle joint prosthetic (AJP) that serves as an attachment to baseline AFP’s, with the aim of facilitating better stance mechanics via the restoration of ankle joint mechanisms. The work is presented in three core sections: Part 1 explains the rationale as to why adequately replicating natural stance mechanics is an appropriate need; Part 2 presents the design of the modular low-cost AJP that utilises only simple mechanical elements; and Part 3 presents the experimental quantification of the impact the AJP has on stance mechanics of a baseline AFP (Otto Bock 1D10) in a simulation of the TT amputee walking gait cycle, via the use of three able-bodied participants and a pseudo-prosthesis. Results: The results indicate that the AJP significantly improves the stance mechanics of the baseline AFP. During forefoot rollover a stable joint moment and an increase in joint range of motion (RoM) was observed, yielding a decrease in ankle stiffness. During initial weight acceptance of early stance, an increase in joint RoM displays the restoration of controlled plantarflexion, which indicates an improved transition from heelstrike to footflat. This is a critical mechanism that facilitates stability control during weight acceptance, and the results suggest that the designed AJP is performing better in this regard than its closest functional competitor. However, equipment errors limited the ability to accurately report on ankle stiffness of this phase. Conclusions: Overall the final conclusions are that the designed AJP improves rollover shapes of the baseline AFP, eases phase transitions, and facilitates stability control and forward tibial progression. In combination with the low cost price (±50 USD), its ease of assembly and modular design, the AJP is thus a preferable option for low-income amputees in developing countries. Finally, there is significant evidence of functional and mechanical reliability, and therefore testing of the device can progress to a clinical study involving amputee participants.

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Michaels, Nathaniel I. "A Modular Robotic AFO for detecting phase changes during Walking Gait." Digital WPI, 2020. https://digitalcommons.wpi.edu/etd-dissertations/599.

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The focus of this paper is on the development of a modular AFO (Ankle Foot Orthosis) subsystem for the greater L.A.R.R.E (Legged Anthropomorphic Robotic Rehab Exoskeleton) Exoskeleton. The main role of the AFO device is in the role of medical rehabilitation, by providing passively-powered dorsiexion support to the user's ankle in order to prevent foot drop. It is able to accomplish this role through the use of a torsional spring attached to the ankle joint. Additionally, the AFO must also be able to provide sensory-feedback to the greater L.A.R.R.E system in order to help control walking gait. It can detect the orientation of the ankle through the use of both a potentiometer and IMU attached at the ankle joint, and it can detect which part of the foot is in contact with the ground through a specially-designed tactile sensor embedded within the sole of the AFO. This sensor consists of Force-Sensing Resistor sensors encased within a polyurethane rubber mold to provide protection from wear and tear as well as provide a rough surface to keep the device from slipping. The development of this "Sole-Sensor" was fairly extensive, with multiple iterations of the sensor being developed over the course of the project. It was found that Sole-Sensor works best when the resin geometry is shaped in such a way that it concentrates all forces applied on it directly above the FSRs. The development of a working Sole-Sensor subsystem allowed a proper test of the Right-foot AFO system within a VICON Motion-Capture room to test Foot-position detection and Center-of-Pressure point tracking. Translating the AFO CoP point into the VICON Lab's "World Frame" and comparing it to the independently calculated Force-Plate CoP point shows a maximum position displacement of +/- 3cm along the AFO's X-axis and +/- 5cm along the Y-axis.

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George-Reichley, Debra G. "Potential muscle function during the swing phase of stroke gait an induced acceleration study /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 51 p, 2008. http://proquest.umi.com/pqdweb?did=1481669451&sid=10&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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14

Pantall, Annette. "Pattern analysis of surface electromyographic activity from hip joint muscles during the stance phase in osseo-integrated transfemoral amputees." Thesis, University of Surrey, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492972.

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Although there have been considerable developments in surgical methods and prosthetic limbs, one quarter of transfemoral (TF) amputees remain dissatisfied with their prostheses. Function could be improved by establishing a communication link between the prosthetic limb and the residual limb. A potential non-invasive method of linking the limbs could be made by using surface electromyography (sEMG). The recent development of the osseo-integrated prosthesis (OP) allows electrodes to be freely attached without interference from the socket. This study's objective was to investigate patterns of sEMG in TF amputees fitted with OPs during the stance phase of gait.

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15

Montgomery, Whitney S. "Development and Application of a Virtual Reality Stumble Method to Test an Angular Velocity Control Orthosis." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/24225.

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The Ottawalk-Speed (OWS) orthosis prevents knee collapse in stumble situations. The purpose of this study was to develop a virtual stumble perturbation to measure OWS response to a knee collapse when walking. A new split speed perturbation was developed for the CAREN virtual reality system. This perturbation induced a stumble with increased knee flexion for five able-bodied participants, with either a hopping or stopping recovery strategy. Three knee-ankle-foot orthosis users were subjected to five stumble trials while wearing the OWS. OWS participants used a straight-legged recovery strategy, and extended the knee through recovery weight acceptance. Therefore, the split speed perturbation was not appropriate to measure OWS response to a stumble since knee collapse did not occur. The OWS allowed free knee motion during gait. Further study is required to measure OWS response during a stumble with a knee collapse event.

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16

Moser, David. "Application of angular rate gyroscopes for the analysis of swing phase control in transfemoral amputee gait." Thesis, University of Surrey, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.493049.

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Microprocessor controlled knee prostheses require expertise and programming skill to setup the swing phase damping performance for different walking speeds. There is a lack of suitable sensing and analysis means to quantify control performance and assist the setup process thereby hindering the development of self-optimizing prostheses. In this project the application of miniature gyroscopes was explored as a means to quantify the swing phase control of transfemoral (TF) amputees. The stride-to-stride repeatability of locomotion and the timing and coordination of knee segment motions were investigated as potential indicators of prosthetic swing control performance.

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17

Vahedipour, Annie. "UNCOVERING THE STRUCTURE OF THE MOUSE GAIT CONTROLLER USING MECHANICAL AND NEUROMUSCULAR PERTURBATION OF FREELY RUNNING MICE." Diss., Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/484909.

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Bioengineering
Ph.D.
Locomotion is essential to survival in most animals. Studies have shown that animals, including humans, choose a gait that minimizes the risk of injury and maximizes energetic efficiency. Individuals often encounter obstacles and perturbations during normal locomotion, from which they must recover. Despite the importance of understanding the mechanisms that enable recovery from perturbations, ethical and experimental challenges have prevented full exploration of these in legged systems. A powerful paradigm with which to tackle this difficulty would be the application of external and internal manipulation of the nervous system. These perturbations could target how gait is regulated and how the neural systems process sensory information to control locomotion during an unexpected perturbation. Here we present data on the response of female mice to rapid, precisely timed, and spatially confined mechanical perturbations applied by a treadmill system. Our data elucidate that after the mechanical perturbation, the mouse gait response is anisotropic, preferring deviations away from the trot towards bounding, over those towards other gaits, such as walk or pace. We quantified this shift by projecting the observed gait onto the line between trot and bound, in the space of quadrupedal gaits. We call this projection λ. For λ=0, the gait is the ideal trot; for λ=±π, it is the ideal bound. We found that the substrate perturbation caused a significant shift in λ towards bound during the stride in which the perturbation occurred and the following stride (linear mixed effects model: Δλ=0.26±0.07 and Δλ=0.21±0.07, respectively; random effect for animal, p<0.05 for both strides, n = 8 mice). We hypothesize that this is because the bounding gait is better suited to rapid acceleration or deceleration, and an exploratory analysis of jerk showed that it was significantly correlated with λ (p<0.05). To evaluate whether the same structure of gait controller exists when undergoing an entirely different class of manipulation, we applied an internal, neuromuscular perturbation. We directly stimulated the lateral gastrocnemius muscle of mice using implanted electrodes and a custom magnetic headstage. We found that the electrical muscle stimulation caused a significant shift in λ towards bound in trials where the stimulation occurred during the swing phase (linear mixed effects model: Δλ=0.23±0.06 and Δλ=0.28±0.06; for the stride during and after the stimulation, respectively; random effect for animal, p<0.05 for both, n = 7 mice). Understanding how gait is controlled under perturbations can give insight into the neuromechanical basis of locomotion, aid in diagnosing gait pathologies, and aid the design of more agile robots.
Temple University--Theses

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18

Vahedipour, Annie. "gait.mp4." Diss., Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/508528.

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Bioengineering
Ph.D.
Locomotion is essential to survival in most animals. Studies have shown that animals, including humans, choose a gait that minimizes the risk of injury and maximizes energetic efficiency. Individuals often encounter obstacles and perturbations during normal locomotion, from which they must recover. Despite the importance of understanding the mechanisms that enable recovery from perturbations, ethical and experimental challenges have prevented full exploration of these in legged systems. A powerful paradigm with which to tackle this difficulty would be the application of external and internal manipulation of the nervous system. These perturbations could target how gait is regulated and how the neural systems process sensory information to control locomotion during an unexpected perturbation. Here we present data on the response of female mice to rapid, precisely timed, and spatially confined mechanical perturbations applied by a treadmill system. Our data elucidate that after the mechanical perturbation, the mouse gait response is anisotropic, preferring deviations away from the trot towards bounding, over those towards other gaits, such as walk or pace. We quantified this shift by projecting the observed gait onto the line between trot and bound, in the space of quadrupedal gaits. We call this projection λ. For λ=0, the gait is the ideal trot; for λ=±π, it is the ideal bound. We found that the substrate perturbation caused a significant shift in λ towards bound during the stride in which the perturbation occurred and the following stride (linear mixed effects model: Δλ=0.26±0.07 and Δλ=0.21±0.07, respectively; random effect for animal, p<0.05 for both strides, n = 8 mice). We hypothesize that this is because the bounding gait is better suited to rapid acceleration or deceleration, and an exploratory analysis of jerk showed that it was significantly correlated with λ (p<0.05). To evaluate whether the same structure of gait controller exists when undergoing an entirely different class of manipulation, we applied an internal, neuromuscular perturbation. We directly stimulated the lateral gastrocnemius muscle of mice using implanted electrodes and a custom magnetic headstage. We found that the electrical muscle stimulation caused a significant shift in λ towards bound in trials where the stimulation occurred during the swing phase (linear mixed effects model: Δλ=0.23±0.06 and Δλ=0.28±0.06; for the stride during and after the stimulation, respectively; random effect for animal, p<0.05 for both, n = 7 mice). Understanding how gait is controlled under perturbations can give insight into the neuromechanical basis of locomotion, aid in diagnosing gait pathologies, and aid the design of more agile robots.
Temple University--Theses

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19

Vahedipour, Annie. "oneafter_animation.mp4." Diss., Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/508529.

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Abstract:

Bioengineering
Ph.D.
Locomotion is essential to survival in most animals. Studies have shown that animals, including humans, choose a gait that minimizes the risk of injury and maximizes energetic efficiency. Individuals often encounter obstacles and perturbations during normal locomotion, from which they must recover. Despite the importance of understanding the mechanisms that enable recovery from perturbations, ethical and experimental challenges have prevented full exploration of these in legged systems. A powerful paradigm with which to tackle this difficulty would be the application of external and internal manipulation of the nervous system. These perturbations could target how gait is regulated and how the neural systems process sensory information to control locomotion during an unexpected perturbation. Here we present data on the response of female mice to rapid, precisely timed, and spatially confined mechanical perturbations applied by a treadmill system. Our data elucidate that after the mechanical perturbation, the mouse gait response is anisotropic, preferring deviations away from the trot towards bounding, over those towards other gaits, such as walk or pace. We quantified this shift by projecting the observed gait onto the line between trot and bound, in the space of quadrupedal gaits. We call this projection λ. For λ=0, the gait is the ideal trot; for λ=±π, it is the ideal bound. We found that the substrate perturbation caused a significant shift in λ towards bound during the stride in which the perturbation occurred and the following stride (linear mixed effects model: Δλ=0.26±0.07 and Δλ=0.21±0.07, respectively; random effect for animal, p<0.05 for both strides, n = 8 mice). We hypothesize that this is because the bounding gait is better suited to rapid acceleration or deceleration, and an exploratory analysis of jerk showed that it was significantly correlated with λ (p<0.05). To evaluate whether the same structure of gait controller exists when undergoing an entirely different class of manipulation, we applied an internal, neuromuscular perturbation. We directly stimulated the lateral gastrocnemius muscle of mice using implanted electrodes and a custom magnetic headstage. We found that the electrical muscle stimulation caused a significant shift in λ towards bound in trials where the stimulation occurred during the swing phase (linear mixed effects model: Δλ=0.23±0.06 and Δλ=0.28±0.06; for the stride during and after the stimulation, respectively; random effect for animal, p<0.05 for both, n = 7 mice). Understanding how gait is controlled under perturbations can give insight into the neuromechanical basis of locomotion, aid in diagnosing gait pathologies, and aid the design of more agile robots.
Temple University--Theses

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20

Vahedipour, Annie. "during_animation.mp4." Diss., Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/508530.

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Bioengineering
Ph.D.
Locomotion is essential to survival in most animals. Studies have shown that animals, including humans, choose a gait that minimizes the risk of injury and maximizes energetic efficiency. Individuals often encounter obstacles and perturbations during normal locomotion, from which they must recover. Despite the importance of understanding the mechanisms that enable recovery from perturbations, ethical and experimental challenges have prevented full exploration of these in legged systems. A powerful paradigm with which to tackle this difficulty would be the application of external and internal manipulation of the nervous system. These perturbations could target how gait is regulated and how the neural systems process sensory information to control locomotion during an unexpected perturbation. Here we present data on the response of female mice to rapid, precisely timed, and spatially confined mechanical perturbations applied by a treadmill system. Our data elucidate that after the mechanical perturbation, the mouse gait response is anisotropic, preferring deviations away from the trot towards bounding, over those towards other gaits, such as walk or pace. We quantified this shift by projecting the observed gait onto the line between trot and bound, in the space of quadrupedal gaits. We call this projection λ. For λ=0, the gait is the ideal trot; for λ=±π, it is the ideal bound. We found that the substrate perturbation caused a significant shift in λ towards bound during the stride in which the perturbation occurred and the following stride (linear mixed effects model: Δλ=0.26±0.07 and Δλ=0.21±0.07, respectively; random effect for animal, p<0.05 for both strides, n = 8 mice). We hypothesize that this is because the bounding gait is better suited to rapid acceleration or deceleration, and an exploratory analysis of jerk showed that it was significantly correlated with λ (p<0.05). To evaluate whether the same structure of gait controller exists when undergoing an entirely different class of manipulation, we applied an internal, neuromuscular perturbation. We directly stimulated the lateral gastrocnemius muscle of mice using implanted electrodes and a custom magnetic headstage. We found that the electrical muscle stimulation caused a significant shift in λ towards bound in trials where the stimulation occurred during the swing phase (linear mixed effects model: Δλ=0.23±0.06 and Δλ=0.28±0.06; for the stride during and after the stimulation, respectively; random effect for animal, p<0.05 for both, n = 7 mice). Understanding how gait is controlled under perturbations can give insight into the neuromechanical basis of locomotion, aid in diagnosing gait pathologies, and aid the design of more agile robots.
Temple University--Theses

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21

Vahedipour, Annie. "twobefore_animation.mp4." Diss., Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/508531.

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Abstract:

Bioengineering
Ph.D.
Locomotion is essential to survival in most animals. Studies have shown that animals, including humans, choose a gait that minimizes the risk of injury and maximizes energetic efficiency. Individuals often encounter obstacles and perturbations during normal locomotion, from which they must recover. Despite the importance of understanding the mechanisms that enable recovery from perturbations, ethical and experimental challenges have prevented full exploration of these in legged systems. A powerful paradigm with which to tackle this difficulty would be the application of external and internal manipulation of the nervous system. These perturbations could target how gait is regulated and how the neural systems process sensory information to control locomotion during an unexpected perturbation. Here we present data on the response of female mice to rapid, precisely timed, and spatially confined mechanical perturbations applied by a treadmill system. Our data elucidate that after the mechanical perturbation, the mouse gait response is anisotropic, preferring deviations away from the trot towards bounding, over those towards other gaits, such as walk or pace. We quantified this shift by projecting the observed gait onto the line between trot and bound, in the space of quadrupedal gaits. We call this projection λ. For λ=0, the gait is the ideal trot; for λ=±π, it is the ideal bound. We found that the substrate perturbation caused a significant shift in λ towards bound during the stride in which the perturbation occurred and the following stride (linear mixed effects model: Δλ=0.26±0.07 and Δλ=0.21±0.07, respectively; random effect for animal, p<0.05 for both strides, n = 8 mice). We hypothesize that this is because the bounding gait is better suited to rapid acceleration or deceleration, and an exploratory analysis of jerk showed that it was significantly correlated with λ (p<0.05). To evaluate whether the same structure of gait controller exists when undergoing an entirely different class of manipulation, we applied an internal, neuromuscular perturbation. We directly stimulated the lateral gastrocnemius muscle of mice using implanted electrodes and a custom magnetic headstage. We found that the electrical muscle stimulation caused a significant shift in λ towards bound in trials where the stimulation occurred during the swing phase (linear mixed effects model: Δλ=0.23±0.06 and Δλ=0.28±0.06; for the stride during and after the stimulation, respectively; random effect for animal, p<0.05 for both, n = 7 mice). Understanding how gait is controlled under perturbations can give insight into the neuromechanical basis of locomotion, aid in diagnosing gait pathologies, and aid the design of more agile robots.
Temple University--Theses

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22

Vahedipour, Annie. "twoafter_animation.mp4." Diss., Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/508533.

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Abstract:

Bioengineering
Ph.D.
Locomotion is essential to survival in most animals. Studies have shown that animals, including humans, choose a gait that minimizes the risk of injury and maximizes energetic efficiency. Individuals often encounter obstacles and perturbations during normal locomotion, from which they must recover. Despite the importance of understanding the mechanisms that enable recovery from perturbations, ethical and experimental challenges have prevented full exploration of these in legged systems. A powerful paradigm with which to tackle this difficulty would be the application of external and internal manipulation of the nervous system. These perturbations could target how gait is regulated and how the neural systems process sensory information to control locomotion during an unexpected perturbation. Here we present data on the response of female mice to rapid, precisely timed, and spatially confined mechanical perturbations applied by a treadmill system. Our data elucidate that after the mechanical perturbation, the mouse gait response is anisotropic, preferring deviations away from the trot towards bounding, over those towards other gaits, such as walk or pace. We quantified this shift by projecting the observed gait onto the line between trot and bound, in the space of quadrupedal gaits. We call this projection λ. For λ=0, the gait is the ideal trot; for λ=±π, it is the ideal bound. We found that the substrate perturbation caused a significant shift in λ towards bound during the stride in which the perturbation occurred and the following stride (linear mixed effects model: Δλ=0.26±0.07 and Δλ=0.21±0.07, respectively; random effect for animal, p<0.05 for both strides, n = 8 mice). We hypothesize that this is because the bounding gait is better suited to rapid acceleration or deceleration, and an exploratory analysis of jerk showed that it was significantly correlated with λ (p<0.05). To evaluate whether the same structure of gait controller exists when undergoing an entirely different class of manipulation, we applied an internal, neuromuscular perturbation. We directly stimulated the lateral gastrocnemius muscle of mice using implanted electrodes and a custom magnetic headstage. We found that the electrical muscle stimulation caused a significant shift in λ towards bound in trials where the stimulation occurred during the swing phase (linear mixed effects model: Δλ=0.23±0.06 and Δλ=0.28±0.06; for the stride during and after the stimulation, respectively; random effect for animal, p<0.05 for both, n = 7 mice). Understanding how gait is controlled under perturbations can give insight into the neuromechanical basis of locomotion, aid in diagnosing gait pathologies, and aid the design of more agile robots.
Temple University--Theses

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23

Vahedipour, Annie. "onebefore_animation.mp4." Diss., Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/508534.

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Abstract:

Bioengineering
Ph.D.
Locomotion is essential to survival in most animals. Studies have shown that animals, including humans, choose a gait that minimizes the risk of injury and maximizes energetic efficiency. Individuals often encounter obstacles and perturbations during normal locomotion, from which they must recover. Despite the importance of understanding the mechanisms that enable recovery from perturbations, ethical and experimental challenges have prevented full exploration of these in legged systems. A powerful paradigm with which to tackle this difficulty would be the application of external and internal manipulation of the nervous system. These perturbations could target how gait is regulated and how the neural systems process sensory information to control locomotion during an unexpected perturbation. Here we present data on the response of female mice to rapid, precisely timed, and spatially confined mechanical perturbations applied by a treadmill system. Our data elucidate that after the mechanical perturbation, the mouse gait response is anisotropic, preferring deviations away from the trot towards bounding, over those towards other gaits, such as walk or pace. We quantified this shift by projecting the observed gait onto the line between trot and bound, in the space of quadrupedal gaits. We call this projection λ. For λ=0, the gait is the ideal trot; for λ=±π, it is the ideal bound. We found that the substrate perturbation caused a significant shift in λ towards bound during the stride in which the perturbation occurred and the following stride (linear mixed effects model: Δλ=0.26±0.07 and Δλ=0.21±0.07, respectively; random effect for animal, p<0.05 for both strides, n = 8 mice). We hypothesize that this is because the bounding gait is better suited to rapid acceleration or deceleration, and an exploratory analysis of jerk showed that it was significantly correlated with λ (p<0.05). To evaluate whether the same structure of gait controller exists when undergoing an entirely different class of manipulation, we applied an internal, neuromuscular perturbation. We directly stimulated the lateral gastrocnemius muscle of mice using implanted electrodes and a custom magnetic headstage. We found that the electrical muscle stimulation caused a significant shift in λ towards bound in trials where the stimulation occurred during the swing phase (linear mixed effects model: Δλ=0.23±0.06 and Δλ=0.28±0.06; for the stride during and after the stimulation, respectively; random effect for animal, p<0.05 for both, n = 7 mice). Understanding how gait is controlled under perturbations can give insight into the neuromechanical basis of locomotion, aid in diagnosing gait pathologies, and aid the design of more agile robots.
Temple University--Theses

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Chiu, Shiu-Ling, and Shiu-Ling Chiu. "Assessing Inter-joint Coordination during Walking." Thesis, University of Oregon, 2012. http://hdl.handle.net/1794/12543.

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Coordination indicates the ability to assemble and maintain a series of proper relations between joints or segments during motions. In Dynamical Systems Theory (DST), movement patterns are results of a synergistic organization of the neuromuscular system based on the constraints of anatomical structures, environmental factors, and movement tasks. Human gait requires the high level of neuromuscular control to regulate the initiation, intensity and adaptability of movements. To better understand how the neuromuscular system organizes and coordinates movements during walking, examination of single joint kinematics and kinetics alone may not be sufficient. Studying inter-joint coordination will provide insights into the essential timing and sequencing of neuromuscular control over biomechanical degrees of freedom, and the variability of inter-joint coordination would reflect the adaptability of such control. Previous studies assessing inter-joint coordination were mainly focused on neurological deficiencies, such as stroke or cerebral palsy. However, information on how inter-joint coordination is modulated with different constraints, such as walking speeds, aging, brain injury or joint dysfunctions, are limited. This knowledge could help us in identifying the potential risks during walking and improve the performance of individuals with movement impairments. The purpose of the present study was to investigate the properties of inter-joint coordination pattern and variability during walking with different levels of neuromuscular system perturbations using a DST approach, including an overall neuromuscular systemic degeneration, a direct insult to the brain, and a joint disease. We found that aging seemed to reduce the pattern adaptability of neuromuscular control. Isolated brain injury and joint disease altered the coordination pattern and exaggerated the variability, indicating a poor neuromuscular control. To improve gait performances for different populations, clinical rehabilitation should be carefully designed as different levels of neuromuscular system constraints would lead to different needs for facilitating appropriate coordinative movement. This dissertation includes both previously published/unpublished and coauthored material.

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25

Calvitti, Alan. "Phase Locking in Coupled Oscillators as Hybrid Automata." Case Western Reserve University School of Graduate Studies / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=case1083095786.

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26

Mendes, Ester Francisca. ""Comparação de parâmetros cinemáticos da marcha entre indivíduos jovens e idosos em tarefas de ateração do comprimento preferido do passo"." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/39/39132/tde-08072005-164641/.

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O presente estudo teve como objetivo verificar o efeito de restrições no comprimento do passo sobre o desempenho da marcha em adultos e idosos, supondo que: (a) quando submetidos a condições de marcha semelhantes, adultos e idosos apresentam desempenhos similares em alguns parâmetros da marcha; (b) as restrições no comprimento do passo interferem sobre a velocidade de deslocamento e sobre a relação de fase entre braço e perna da mesma forma para adultos e idosos; (c) as restrições no comprimento de passo causam maior impacto sobre a variabilidade das relações de fase entre membro superior nos idosos. Para verificar estas hipóteses, nove adultos jovens e oito idosos foram filmados em três tarefas: marcha regular, aumento de passo e diminuição do passo. As comparações foram feitas em função das seguintes variáveis: velocidade de marcha, cadência, razão entre o comprimento do passo e o comprimento do membro, amplitude de variação angular do tornozelo, amplitude de variação angular do membro superior, relação de fase e variabilidade da relação de fase entre os membros superior e inferior direitos. Os resultados encontrados revelaram que o padrão de marcha dos idosos apresentou-se semelhante ao de adultos em muitos aspectos. As restrições no comprimento de passo levaram a modificações significativas da velocidade de deslocamento para adultos e idosos, sugerindo que parte das modificações relacionadas ao padrão de marcha do idoso estão relacionados à diminuição no comprimento do passo. A coordenação de movimentos, analisada através da relação de fase entre membros superior e inferior direito, mostrou ser influenciada pela tarefa, enquanto a estabilidade da coordenação entre braços e pernas não foi afetada pela restrição do passo. Estes achados comprovam a hipótese formulada inicialmente, de similaridade das características adaptativas entre os dois grupos etários. A interpretação destes resultados permite concluir que: (a) em marcha regular, adultos e idosos apresentaram desempenhos semelhantes; (b) a restrição de comprimento de passo exerceu efeito significativo sobre a velocidade de deslocamento, sobre a amplitude de movimentação do membro superior e sobre a relação de fase entre membro superior e inferior igualmente para adultos e idosos e (c) a amplitude de movimentação do tornozelo e a variabilidade da relação de fase não foram alterados em função da restrição na amplitude do passo.
The main purpose of this study was verifying the effect of step length restrictions on gait performance of young and old aged, assuming that: (a) when submitted to similar gait conditions, young and old aged presents analogous performance in some gait parameters; (b) the step length restrictions intervene on gait velocity an phase relation between arm and leg in the same way for young and old aged; (c) the step length restrictions cause a larger impact on phase relations variability between superior and inferior limbs for old aged. In order to verify these hypothesis, nine young adults and eight old-aged was filmed on three tasks: regular gait, increase on step length and decrease on step length. The comparisons was made to the following variables: gait velocity, cadency, step length and leg length rate, amplitude of ankle angular variation, amplitude of arm angular variation, phase relation and phase relation variability between right superior and right inferior limbs. The results revealed that the old-aged gait pattern was similar to the adult pattern in considerably aspects. Step length restrictions carried to significative changes on gait velocity for young and old aged, suggesting that part of modifications on old people gait pattern are related to decrease on step length. The movement coordination, analyzed by phase relation between right superior and right inferior limbs was influenced by task condition but not the stability of coordination between arm and legs. These findings corroborates the initial hypothesis, about the similarity of the adaptative characteristics between both groups. The interpretation of these results allows concluding that: (a) on regular gait, young and old aged had similar performance; (b) the step length alterations exerted significative effect over gait velocity, amplitude of arm angular variation and phase relations between superior and inferior limbs on the same way for young and old aged; (c) the task condition had no influence over the amplitude of ankle movement neither over variability of phase relations.

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Porto, Jaqueline Mello. "Associação entre função muscular do quadril e do tronco, equilíbrio e funcionalidade em idosos da comunidade." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/17/17152/tde-04012017-113909/.

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Estudos pregressos têm investigado causas e fatores de risco para quedas e incapacidade funcional em idosos. Porém, no que se refere a fatores biomecânicos envolvidos no desempenho funcional e controle postural, a contribuição dos grupos musculares proximais de quadril e de tronco ainda recebe pouca atenção. Assim, o objetivo deste estudo foi verificar a associação entre a função muscular dos abdutores e adutores do quadril e dos extensores e flexores do tronco com o desempenho do equilíbrio semi-estático e dinâmico e da funcionalidade de idosos independentes que vivem na comunidade. Métodos: oitenta e um idosos de ambos os sexos foram submetidos à avaliação do equilíbrio e da funcionalidade por meio dos testes: (1) marcha tandem sobre a plataforma de força Balance Master (Neurocom International Inc., Clackamas, OR) para obtenção das variáveis velocidade da marcha tandem e velocidade de oscilação corporal ao final da marcha tandem; e (2) testes clínicos de apoio unipodal e Timed Up and Go (TUG). Também foram submetidos à avaliação da função muscular em dinamômetro isocinético (Biodex System 4 Pro, Nova York, EUA) por meio de 3 contrações isométricas máximas de abdução e adução do quadril e flexão e extensão do tronco para obtenção das variáveis pico de torque (PT) e taxa de desenvolvimento de força (TDF) proporcionais ao peso corporal. Após aplicação do teste de normalidade de Shapiro-Wilk, foi realizado teste de correlação de Pearson (dados com distribuição normal) e de Spearman (dados com distribuição não-normal). Para aquelas variáveis com coeficiente de correlação significativo, foi aplicado teste de regressão linear para quantificar o índice de determinação (r2) da função muscular do quadril e tronco no equilíbrio e funcionalidade de idosos. Foi adotado nível de significância de 5% (p < 0,05). Resultados: houve correlação com índice de determinação significativo do PT dos grupos musculares do quadril e do tronco sobre o desempenho dos testes de equilíbrio e funcionalidade. Em relação à TDF, foi encontrada correlação com índice de determinação significativo da TDF de abdução de quadril e de extensão de tronco sobre a velocidade de oscilação ao final da marcha tandem e sobre o TUG e também da TDF de extensão de tronco sobre o apoio unipodal. Conclusões: esses 10 achados podem ser clinicamente relevantes considerando que (1) diferentes parâmetros da função muscular (como PT e TDF) apresentam diferentes estratégias de intervenção para seu aprimoramento e que (2) problemas de equilíbrio e/ou de funcionalidade em idosos podem estar associados com comprometimentos da TDF e do PT da musculatura proximal, os quais são parâmetros passíveis de intervenção.
Previous studies have investigated causes and risk factors for falls and functional disability in the elderly. However, regarding biomechanical factors involved in the functional performance and postural control, the contribution of the proximal muscle groups of the hip and trunk still receives little attention. The objective of this study was to assess the association between muscle function of hip abductors and adductors and trunk flexors and extensors muscles with the performance of static and dynamic balance and functionality of community-dwelling older adults. Methods: eighty-one elderly of both sexes underwent assessment of balance and functionality through: (1) tandem gait test on the Balance Master force platform (Neurocom International Inc., Clackamas, OR) to obtain the variable tandem gait speed and body sway velocity in the end of tandem gait; and (2) clinical tests of single-leg stance and Timed Up and Go (TUG). The participants also underwent assessment of muscle function in isokinetic dynamometer (Biodex System 4 Pro, New York, USA) through 3 maximal isometric contractions of abduction and adduction of the hip and flexion and extension of the trunk to obtain the variables peak torque (PT) and rate of force development (RFD) in proportion to body weight. The Shapiro-Wilk normality test was performed and then, Pearson correlation test (data with normal distribution) and Spearman (data with non-normal distribution) were applied. Linear regression test was applied to quantify the determination index (r2) of muscle function of the hip and trunk in balance and functionality of the elderly for those variables with significant correlation coefficient. It was adopted a significance level of 5% (p < 0.05). Results: there was correlation with a significant determination index of PT of muscle groups of the hip and trunk in the performance of balance and functionality tests. Regarding the RFD, it was found correlation with significant determination index of RFD of the hip abduction and trunk extension in the body sway velocity in the end of tandem gait and TUG; and of RFD of the trunk extension in single-leg stance. Conclusions: These findings may be clinically relevant considering that (1) different parameters of muscle function (such as PT and RDF) have different intervention strategies for their improvement and (2) problems of balance and / or functionality in the elderly may be 12 associated with impairments of RFD and PT of proximal muscles, which are parameters that can be treated.

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28

Guillebastre, Bastien. "Effets du port d’orthèses de type releveur de pied aux caractéristiques mécaniques variées sur le comportement postural et locomoteur : cas de patients présentant une atteinte du nerf sciatique poplité externe ou la maladie de Charcot-Marie-Tooth." Thesis, Saint-Etienne, 2011. http://www.theses.fr/2011STET001T/document.

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Dans le secteur industriel, la nécessité de fournir des données cliniques lors de la mise sur le marché d’un nouveau dispositif médical s’est sensiblement accrue suite à de récentes évolutions juridiques. L’objectif de ce travail de thèse était de recueillir des données cliniques relatives à l’utilisation d’un nouveau modèle d’orthèse de type releveur de pied pour valider son intérêt vis-à-vis de produits standards. Pour formuler des hypothèses raisonnées et interpréter objectivement ces données, la connaissance des caractéristiques mécaniques des orthèses étudiées a constitué l’étape préalable nécessaire. Après s’être assuré de la faisabilité et de la pertinence du protocole expérimental sur des sujets sains, l’analyse des effets du port des dispositifs lors de tâches motrices élémentaires que sont la station debout et la marche chez des patients (avec atteinte uni ou bilatérale, d’origine périphérique, des muscles fléchisseurs dorsaux de cheville) a constitué le cœur de nos investigations. Celles-ci ont ainsi pu mettre en évidence que le port d’orthèse induit des effets communs et d’autres spécifiques à chaque modèle. Dès lors, de façon originale, nous nous sommes proposés d’identifier, par des moyens simples et rapides, les patients qui tirent davantage profit d’un des modèles d’orthèse. Outre le prérequis indispensable qui est l’acceptation de l’appareillage par le patient, nos résultats précisent que le dispositif orthopédique le plus adapté est celui qui compense le(s) déficit(s) en restaurant la fonction motrice, sans contraindre les capacités préservées
In the industrial field, the necessity of providing some clinical data during the launching of a new medical device has noticeably increased after some recent legal evolutions. The aim of this thesis was to collect some clinical data concerning the use of a new ankle-foot orthosis in order to confirm its relevance in comparison with standard products. To formulate some reasoned hypotheses and objectively interpret these data, the knowledge of the mechanical characteristics of the studied orthoses has constituted the preliminary necessary step. After checking the feasibility and the relevance of the experimental protocol on healthy subjects, the analysis of the effects of the ankle-foot orthoses during some elementary motor tasks, which are the stance and gait, in patients (suffering from a uni or bilateral affection, of a peripheral origin, ankle dorsal ﬂexor muscles) has been the core of our research. As a consequence, it results from this that the ankle-foot orthosesinfer some common effects and some other, specific to each model. From that moment on, in an original way, we were bound to identify, with some simple and fast ways the patients taking the larger advantage from one of the orthosis models. In addition to the necessary prerequisite which is the acceptance of the equipment by the patient, our results specify that the most adapted orthopaedic device compensates for the deficiency(ies) by restoring the motor function, without restraining the preserved abilities

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29

Ottonello, Dominique Marchelle. "Impact of Passive Range of Motion Exercises and Stretching in Knee Osteoarthritis Pain during Walking." Wright State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=wright1589847790494845.

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30

Chang, Ying-Chi, and 張盈琪. "The Effect of Different Slippers on Human Gait Biomechanical Parameters in Stance Phase." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/92248692036874791813.

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碩士
長榮大學
運動休閒管理學系(所)
101
In this research, human gait biomechanical parameters in stance phase when wearing flip-flops, slipper or barefoot to walk (including walking velocity, the time ratio of heel-contact-ground stage to forefoot-push-off stage, the joint angle of hip, knee and ankle, data of the peak of active force, the peak of impact force, maximum loading rate and moment concerning the force produced by human body when acting to the ground, coefficient of friction in heel-contact-ground and forefoot-push-off stage) were aimed to compare. In experiment, VICON motion analysis system was used to capture relating data when ten male college students without specific injuries in lower extremity wearing blue-white flip-flops, blue-white slipper or barefoot respectively to walk in three different velocities. Statistics were completed by two-way repeated measure ANOVA using SPSS software. Significant level was set at α=.05. Results: 1. Although different slippers and different walking velocity would influence the time ratio of heel-contact-ground stage to forefoot-push-off stage synthetically, different slippers couldn’t affect walking velocity. 2. The peak of impact force and maximum loading rate would influence the performance of shock absorbing. Different slippers and walking velocities would affect these two parameters, but only the maximum loading rate would be affected interactively by different slippers and walking velocities. 3. The peak of active force, maximum and minimum moment, coefficient of friction in heel-contact-ground and forefoot-push-off stage would influence the functional performance of shoe. Different slippers and walking velocities would affect maximum moment respectively and interactively, but only affecting minimum moment, coefficient of friction in heel-contact-ground and forefoot-push-off stage respectively. As for the peak of active force, it would be influenced by different walking velocities respectively and by different slippers and walking velocities interactively. 4. When wearing different slippers and changing different walking velocity to walk, the movement of lower extremity would change. The changing of walking velocity would cause the variation of hip extension and ankle eversion. For these movement including the flexion and extension of knee and ankle joint, different slippers and walking velocities would cause different effects.

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31

Chen, Cheng-Wei, and 陳政偉. "The Biomechanical Behavior of Plantar Fascia during Stance Phase of Gait Cycle - A Finite Element Analysis." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/955z8z.

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碩士
國立臺北科技大學
機電整合研究所
100
The plantar fascia is an important soft tissue for stabilization of the foot arch. It can provide the flexibility to dissipate impact energy during gait cycle. Abnormal load or repeated injuries are the possible factors for plantar fasciitis. According to previous in vitro studies, there are two major loading factors causing plantar fasciitis during gait cycle. One is the weight-bearing load following the mid-stance phase of gait. The other is the windlass effect caused by phalanges winding the plantar fascia during heel rise and terminal period of gait. Although the loading on the plantar fascia during gait cycle was revealed in previous in vitro study, it didn’t describe the magnitude and position of the loads applied on the plantar fascia. Therefore, the aim of the current study was to use dynamic finite element analysis to investigate the biomechanical behavior of the plantar fascia during stance phase of gait cycle, and it’s biomechanical effect on the foot. This study established a three-dimensional finite element foot model with complete plantar fascia structure, and the non-linear material properties of the soft tissues were considered. This model was better than the models created in previous literature which used simple truss element to represent the plantar fascia. In addition, an in-house material testing machine which integrated with ultrasonic graphic system was used to determine the material property of plantar soft tissue. The use of these non-linear material properties could increase the accuracy of the simulation results. The loading and boundary conditions for the finite element analysis of the foot were adopted from the kinematic and kinetic data obtained from gait analysis. The force and stress distributions on the plantar fascia during stance phase were obtained from the dynamic finite element analysis. Because of the windlass effect, a tension force of 1082.4N was found near the junction of plantar fascia and calcaneus during push off. The peak von Mises stress distributions of plantar fascia were 15.58MPa, 15.0MPa and 11.42MPa from medial to lateral aspects of the foot, respectively. The location of the stress concentration on the plantar fascia was consistent with the commonly found locations of plantar fasciitis. The results of this study were validated by comparing the experimental kinematic data, ground reaction force, and plantar pressure distributions. These quantitative data can provide reference for clinicians who treat plantar fasciitis with the strategy of using biomechanical control on the footwear.

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32

Lin, Shih-Cherng, and 林師誠. "The biomechanical effects of different footwear designs on the plantar aponeurosis during stance phase of gait." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/n7ts86.

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博士
中原大學
生物醫學工程研究所
102
The plantar aponeurosis (PA) has long been considered to play an important role in weight-bearing, both in static stance and in dynamic ambulation. Excessive and repeated loading imposed on the PA is believed to be the most likely risk factor for developing plantar fasciitis. Treatment strategies that can diminish factors leading to excessive strain or stress on the PA during the terminal stage of the gait cycle may facilitate a patient's recovery from plantar fasciitis. Foot orthoses and shoe modifications are commonly used in treating the plantar fasciitis. However, the mechanism has not been thoroughly investigated during the entire gait cycle. Therefore, the purpose of this study was to investigate the biomechanical responses of the PA to different insole designs and shoe modifications throughout the stance phase of the gait. Foot kinematic analyses of 10 normal volunteers were performed during gait under the conditions of barefoot, regular shoe (RGS) with flat insole (FI) or carbon fiber insole (CFI), and rocker sole shoe (RSS) with FI or CFI. The shoe cover consisted of transparent polymer, PolyVinyl Chloride, which allowed for accurate measurement of kinematic data since it meant specific areas on the cover could be cut away for direct placement of reflective markers onto the skin. Furthermore, a subject-specific three-dimensional finite element foot model with emphasis on the "tension-only" feature of the PA was constructed to simulate the foot motion. The kinematic data of foot bone motions were collected to serve as the input conditions for the dynamic finite element analysis. The analyses were performed under barefoot, RGS with FI or total contact insole (TCI), and RSS with FI or TCI conditions. The experimental results revealed that the mean of maximum dorsiflexion angle of the 1st MTP joint was measured to be 48.0°±7.3° under the barefoot condition, and decreased significantly to 28.2°±5.7° when wearing RGS with FI, and to 24.1°±5.7° when wearing RGS with CFI. This angle was further decreased to around 13° when wearing RSS with FI or CFI. Subjects wearing footwear alone can increase the minimum medial longitudinal angle and decrease the maximum plantarflexion angle of the metatarsus in relation to the calcaneus, as compared with the barefoot condition, resulting in a flatter medial foot arch. It is suggested that RSS is the most effective footwear for reducing the windlass effect, regardless of the type of insole inserted. The predicted results showed that the TCI provides more benefit in terms of reducing the PA force and the medial PA von Mises stress than the FI during the mid-stance phase. However, no obvious inhibition was found on the windlass effect occurring in the late stance phase. As compared to the RGS, the RSS can provide more reduction in peak PA force. Therefore, in addition to prescribing TCIs to prevent the collapse of the medial longitudinal arch, the RSS should be taken into consideration as a means of inhibiting the windlass effect. The findings in this study provided us with evidence to assist clinicians in finding the appropriate footwear for treating foot disorders such as plantar fasciitis by effectively reducing the windlass effect. Clinical trials should be carried out in the future to validate the suggestions from this study.

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CHEN, LIANG-YU, and 陳亮宇. "Biomechanical Evaluation of Additive-Manufactured Midsoles during Stance Phase of Gait – a Dynamic Finite Element Analysis." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/9jpje3.

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碩士
國立臺北科技大學
製造科技研究所
107
The foot and the ground produce repeated impact when the heel strikes the ground. During this process, the lower limbs are responsible for absorbing these impact forces, and excessive impact forces may cause damage to the foot. For the sake of protecting foot, proper footwear is an important consideration, and the midsole of the footwear can provide impact absorbing function. As additive manufacturing technology advances, many processing technologies that can not be achieved by traditional manufacturing methods are developed. In recent years, such technology has also been applied to the production of commercially available honeycomb-structured shoes, such as Adidas Futurecraft 4D (FC4D) shoes, and they emphasize on better shock absorbing capability. At the same time, some literatures have pointed out that a negative poisson's ratio (NPR) can be applied to impact attenuation devices such as automobile bumpers and packaging materials. Therefore, the purpose of this study is to use dynamic finite element analysis to assess the relationship between the biomechanical benefits of the foot and the energy absorbing efficacies of the midsoles for the Adidas Futurecraft 4D and NPR midsoles. In this study, two honeycomb structures with different internal geometries were established and made according to the standard specifications, and the porosity of the test blocks were defined as 65% (Adidas FC4D) and 67% (NPR). The finite element model of the midsole was simplified by using equivalent element method, and the elemental triaxial compression analysis was performed to verify that the element has the equivalent anisotropic material property of the detailed honeycomb structure. To simulate the change in the plantar pressure when wearing two footwears with different midsole structures during the stance phase. Biomechanical evaluation was performed by using a three-dimensional finite element model of the foot, and the kinematic parameters obtained from gait analysis were brought into the foot model. From the analysis results, the plantar pressure under the calcaneus and the third metatarsal region of the forefoot were compared and the energy absorption of the midsole during stance phase was observed. The results showed that the midsoles of the Adidas FC4D shoes are more effective in plantar pressure reduction than the NPR midsole under the calcaneus and the third metatarsal region. For the percentage of plantar pressure reduction in the calcaneus area, Adidas FC4D midsole is 54% and the NPR shoe midsole is 33%, as compared to the barefoot condition. As for the third metatarsal area, Adidas FC4D midsole is 50% and the NPR midsole is 38%. The energy absorption results of the two hollow midsoles showed that the adidas FC4D midsole is better than that of the NPR midsole during the heel strike and push-off phases, Adidas FC4D midsole can absorb 903 joules of energy and the NPR shoe midsole can absorb 875 joules during heel strike, while the Adidas FC4D midsole can absorb 1368 joules and the NPR midsole can absorb 1200 joules during push-off. When comparing the plantar pressure reduction effects of the midsole and the energy absorption effect, the adidas FC4D midsole is better than the NPR midsole during the stance phase. Therefore, it can absorb more impact energy and decrease the plantar pressure of the foot. This study simplified the finite element model of the honeycomb structured shoes with equivalent elements. This can significantly reduce the number of elements for the honeycomb structure and can shorten the time required for analysis. The finite element model established in this study can be used as a preliminary evaluation tool for new shoes by eliminating unnecessary waste of experimental resources.

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Fang, Hou Chuan, and 侯傳方. "The effect of sliding surface on GRF and knee joint kinetics during stance phase of gait." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/73062883197398290704.

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碩士
臺北巿立體育學院
運動器材研究所
98
The purpose of this study was to investigate the sliding effect on heel kinematics, GRF, and knee joint loading. Heel velocity and displacement, anterior-posterior and vertical GRF, anterior-posterior knee force, and knee torque were collected from 14 healthy male recreational athletes in walking(1.5 ms-1± 5%), running(3.5 ms-1± 5%), and leap-landing in non-sliding and sliding conditions by using reflective markers and motion analysis system. Besides, the knee force and torque were derived from inverse dynamics approach. A paired-t test was used to determine the difference of heel kinematics, GRF, and knee joint loading between non-sliding and sliding trials. The results showed heel velocity and displacement significantly increased in sliding trials. In addition, A-P and vertical GRF, knee A-P force and torque of walking and leap-landing significantly decreased in sliding condition. However, the A-P GRF and knee torque of running showed non-significant difference in sliding trials. Therefore, the effect of sliding condition on heel kinematics and knee joint loading varied in different gait styles.

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35

Lin, Yi-Chia, and 林一嘉. "Effect of Anterior Rocker Sole Shoe Profiles on the Plantar Fascia Loading during Stance Phase of Gait." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/df3a7g.

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碩士
國立臺北科技大學
製造科技研究所
102
Plantar fasciitis is commonly observed in the patients with heel pain. The etiology is multifactorial, such as abnormal foot structure or overuse injury. Both these factors may lead to excessive loading on the plantar fascia, and then impair it. It is obvious that the plantar fascia bears loading during the period of mid-stance phase and push-off phase. As to the push-off phase, the windlass effect is induced by dorsiflexion of the toes, and brings on the peak loading on the plantar fascia. In clinical practice, the anterior rocker sole is a common orthosis prescribed for the treatment of plantar fasciitis. The effect of orthoses to the loading of plantar fascia, however, is not well investigated. For this reason, the gait analysis and dynamic finite element analysis (FEA) were used in this study to investigate the effect of the anterior rocker shoe designs on the loading of planter fascia during the stance phase of gait. A three-dimensional finite element foot model, including the bones, the planter fascia and the other soft tissues, were reconstructed in this study. A total contact insole and the anterior rocker soles with 3 different designs of rocker angle were also created. The kinematic data obtained from the gait analysis was used as the boundary conditions to simulate the motion of the foot with different anterior rocker soles during the stance phase, while the kinetic data was used to validate the results from the FEA. The material property of the plantar soft tissues obtained from our previous study was adopted in this study as well. The result showed that the tensile loading of the planter fascia under barefoot, RBS10°, RBS20° and RBS30° conditions were 1338.2 N, 1077.7 N, 907.5 N and 752.3 N, respectively. The maximal peak von Mises stresses in the plantar fascia near the calcaneal tuberosity calculated 22.2 MPa, 15.49 MPa, 14.04 MPa and 11.87 MPa under barefoot, RBS10°, RBS20° and RBS30° conditions, respectively. As a result, wearing a shoe with larger anterior rocker angle would be able to inhibit the windlass effect, and the peak loading of the plantar fascia will thus be relieved. The validated results from this study can provide a treatment guideline for treatment of plantar fasciitis, and would be benefical to orthotis in the design of orthosis.

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Cheng, Chin-Hung, and 陳志宏. "A Mechanism Design to Simulate Human Ankle during the Stance Phase of Walking." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/44084494684511199067.

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37

Chu, Chun-Gin, and 朱長君. "The Biomechanical Analysis of the Rotation Axis of Foot-Ankle Complex during Stance Phase." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/33567459429617864265.

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碩士
國立成功大學
醫學工程學系
84
The main purpose of the study is to calculate the position, direction and energy of ankle joint axis on foot and shank by using screw axis theory. After constructing a screw axis model for the segments of foot and shank, we can calculate for the position, direction and work along screw axis of ankle joint axis by means of coordinate transformation. Moments of foot and shank segments during normal walking will be measured using a Motion Kinematic measuring system and the foot reaction forces of stance phase will be measured using Kistler force plate. According to the results, the screw axis passes outside the midpoint of a line drawn between the tips of malleoli and moves backward beneath the midpoint of malleoli during normal walking gait cycle. The direction of screw axis is not fixed but the projection ankle of screw axis at transverse plane is getting lager. For the normal subjects, the component force of ground reaction force along the screw axis is high correlated with the projection of screw axis on the Z axis. The energy of foot/ ankle joint is mainly to provide the power for foot and shank. The method used in these study could provide another point of view for the clinic doctors to judge whether the ankle joint is normal or not. Based on the results, we could also help on the design of prosthesis and patients with disorders of foot and ankle.

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38

Zhu, Zhang-Jun, and 朱長君. "The Biomechanical Analysis of the Rotation Axis of Foot-Ankle Complex during Stance Phase." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/67410721164070814880.

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39

Chen, Chi-Chuan, and 陳啟專. "Multibody dynamics Simulation of 3-D human Gait during swing Phase." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/77770651006144105062.

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Tseng, Chien-Yuan, and 曾健源. "A Comparative Study of Square and Open Stance of Forehand Stroke for Tennis during Acceleration Phase." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/66266057924307692437.

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碩士
輔仁大學
體育學系碩士班
101
The purpose of this study was to compare the kinematics of tennis square and open stance forehand stroke during acceleration phase. Six elite male college tennis players participated in this study. With 18 retro-reflective balls installed on participant’s joints, a Mega Speed high-speed camera (120Hz) was able to record the actions of two types of forehand stroke from sagittal plane. The recorded images were digitized by Kwon 3D 3.1 motion analysis system. Differences between two stances were analyzed by t-test for paired samples. The results of this study as following: 1. The ball velocity of square stance forehand stroke during acceleration phase is greater than that of open stance, and the difference is significant (p< .05); however, there were no significant differences between two stances on either maximum velocity of racket or the velocity of impact. 2. During acceleration phase, the distance between participant’s feet and contact point with square stance is significantly greater than that with open stance. (p< .05). But the distances between the contact point and the center body mass do not have remarkable difference. 3. In acceleration phase, the participant with square stance has greater horizontal movement on center of body mass (p< .05), but less vertical movement (p< .05) than that with open stance. Meanwhile, the horizontal movement of racket between two stances are remarkable (p< .05), but not for vertical movement. To conclude, based on Law of Conservation of Momentum, since the movement of acceleration stage of square stance is greater than that of open stance, a tennis ball should get greater momentum for acceleration. Hence, if a tennis player wish to make a faster ball velocity, square stance should be a better choice. Key words: forehand stroke, square stance, open stance

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41

Liu, I.-Kuei, and 劉奕奎. "The Evaluation of Stress Distribution of the Different Layers in Rearfoot Plantar Soft Tissue during Stance Phase." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/48741293827914309854.

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碩士
中原大學
醫學工程研究所
96
Based on the anatomical definition, the human heel fat pad consists of the microchamber layer lying beneath the plantar skin and the macrochamber layer lying near the calcaneus. In previous studies, the heel pad is often considered as a simple structure with homogeneous material owing to some simplifications and limitations. There is few study investigated the biomechanical behavior of the heel pad with both the microchamber and macrochamber layers during human locomotion. Therefore, the purpose of this study was to evaluate the biomechanical behavior of the detailed plantar heel soft tissue structure during stance phase by finite element analysis. In order to construct the detailed finite element model of the rearfoot, magnetic resonance imaging (MRI) system was used to capture the right foot images from a healthy male subject. A specially-designed loading device was integrated with an ultrasonic imaging system to measure the material properties of different plantar soft tissue layers as well. Motion analysis was performed to obtain the kinematic and kinetic data of the right foot of the same subject who received MRI scanning. Finally, the results from finite element analysis were compared with the data from plantar pressure measurement to verify the accuracy of computer simulation. The result show that the maximum stress which concentrated around the medial calcaneal tuberosity was about 250 KPa. Moreover, there was a high shear stress of 150 KPa found in the inner soft tissue. About 90% of the heel fat pad strain was found in the macrochamber layer when the plantar soft tissue was subjected to loading. On the other hand, only about 10% of the heel fat pad strain was found in the microchamber layer. Therefore, when considering the plantar soft tissue as a nonhomogeneous material not only can present the realistic loading response of the plantar soft tissue, but also show similar strain results from both finite element analysis and experimental measurement. For this reason, the presented quantitative data in the current study can provide meaningful reference for the prevention and treatment of foot disease for clinical applications.

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LIN, HUI-FEN, and 林慧芬. "Prediction of muscle forces of lower extremities during double support phase of gait." Thesis, 1990. http://ndltd.ncl.edu.tw/handle/29337937553780546773.

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43

Lin, Sheng-Yu, and 林省佑. "A Comparative Study on Square and Open Stance of Backhand Stroke for Male Tennis Players during Acceleration Phase." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/23389296297048865849.

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碩士
輔仁大學
體育學系碩士在職專班
103
Abstract The purpose of this study was to compare the kinematics of tennis square and open stance of backhand stroke for male tennis players during acceleration phase. Six elite male college tennis players participated in this study. A Mega Speed high-speed camera (120Hz) was employed to record the actions of two types of backhand stroke from sagittal plane. The recorded images were digitized by Kwon 3D 3.1 motion analysis system. Kinematic differences between two stances of backhand stroke during acceleration phase were analyzed by t-test for paired samples. The results of this study were as following: 1. During acceleration phase, the difference of average ball velocity was significant (p<.05) between two stances of backhand stroke; and the average ball velocity with square stance was greater than that of open stance. 2. There were no significant differences between two stances of backhand stroke on either the maximum velocity of stroke or the maximum velocity of racket; however, the velocity of racket and the maximum velocity of racket with square stance was greater than that of open stance with a slight inclination. A remarkable difference was observed between two type of stances when the maximum velocity of racket was reached (p< .05), and the maximum velocity of racket can be reached at the stroking moment with square stance. 3. The forward displacement of body center of mass (COM) during acceleration phase with square stance of backhand stroke (24.18 ± 5.53 cm) was greater than that with open stance (14.40 ± 5.13 cm); however, the vertical displacement of body COM with open stance (13.46 ± 3.85 cm) was greater than that with square stance (6.84 ± 2.90 cm),and there was significant difference of vertical displacement between the square stance and open stance(p< .05). In conclusion, this study give suggestions for tennis players to choose type of stances for backhand stroke that can generate greater velocity while stroking. Keywords: backhand stroke, square stance, open stance

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44

Gabriela, De A. C. Abbud. "Attentional requirements of walking according to the gait phase and onset of auditory stimuli." Thesis, 2008. http://spectrum.library.concordia.ca/975896/1/MR40860.pdf.

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The influence of an attention demanding cognitive task on each phase of gait was analyzed, using a dual-task paradigm. Electromyography (iEMG) from eight muscles from the dominant leg was collected from 23 participants (age 18-27) while walking on a treadmill at a 20% increase of their self-selected speed and while walking and performing a cognitive task. The cognitive task consisted of subtracting one (EASY) or seven (HARD) from numbers aurally presented. Reaction time (RT) and accurate responses of the cognitive task were recorded. iEMG events were selected according to stimuli onset (0-150 ms, 150-300 ms and 300-450 ms) prior to the phases of gait (double-leg, single- leg and swing). There was a decrease in iEMG amplitude of fibularis longus (p = .013) and vastus lateralis (p = .065) while walking and performing the cognitive task. When stimulus onset was considered, iEMG of medial gastrocnemius (p = .021) and lateral gastrocnemius (p = .004) were reduced during single-leg stance, when stimuli occurred between 300-450 ms prior to this phase. Participants committed more errors and had longer RT on the HARD task. RT was longer when subtracting while walking in comparison to subtracting alone. Young adults expressed dual-task cost in the motor and the cognitive tasks, suggesting that walking requires attention. There was a specific moment (300 ms after stimulus onset) during single-leg stance that dual-task cost occurred. Reasons for this interference and the implications of a reduction in iEMG while walking and performing an attention demanding cognitive task are discussed.

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45

Wyss, Dominik. "Evaluation and Design of a Globally Applicable Rear-locking Prosthetic Knee Mechanism." Thesis, 2012. http://hdl.handle.net/1807/33575.

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A rear locking prosthetic knee joint with a durable, rear Automatic Stance-Phase Lock (ASPL), was developed to investigate the versatility of the (ASPL) mechanism in improving the functionality of prosthetic knees appropriate for a global market. An international survey and a Quality Function Deployment identified deficits with existing prosthetic knee mechanisms and established the most influential design parameters. Work on the knee design was completed following a comparative stability analysis of different knee mechanisms which justified the initial design. Solid models were generated with computer design software and a prototype was produced and structurally tested. Finally, clinical pilot testing was conducted on a unilateral transfemoral amputee, and various gait variables were assessed. As hypothesized, the knee performed close to the level of a conventional six-bar knee providing highly effective stance-phase control and the pilot test showed that improvements to the swing-phase response could further reduce the asymmetry of gait.

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46

Kao, Chiao-Yi, and 高巧宜. "The function of selected lower limb muscles in arch support and center of pressure shifting during stance phase of walking." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/73632564300199481452.

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碩士
國立陽明大學
物理治療暨輔助科技學系
99
Background and purpose: Flexible flatfoot is commonly observed in young children. It is a condition when the medial longitudinal arch of the foot collapses in weight bearing and restores after removing the body weight. The condition is made worse by excessive loose soft tissue in the foot and is linked to various lower extremity injuries, such as patellofemoral pain syndrome, medial tibial stress syndrome and plantar fasciitis. Subjects with flexible flatfoot are usually prescribed exercises for strengthening selected lower limb muscles in order to reduce the risk of getting injury. However, the influence of lower limb muscles, especially the foot intrinsics, on the foot arch support is still unclear. Besides, differences of the center of pressure (COP) excursion between subjects with normal arch and flexible flatfoot were found in the past studies. However, it is unclear if the difference in COP excursion is associated with differential activation of selected lower extremity muscles. The purposes of our study are: (1) to investigate the function of selected lower limb muscles in arch support, and (2) to explore the association between the muscle activation of selected muscles and the displacement of COP during walking. Methods: Twenty flexible-flatfooted subjects and fifteen normal-arched subjects were recruited. The arch height, range of motion of ankle and foot, muscle strength of selected lower extremity muscles were measured in both groups. Then we collected activation of tibialis anterior, preoneus longus and hallucis abductor with surface electromyography and recorded the path of COP while the subjects were walking on a pressure mat system. Statistical Analysis: Independent t test was used to analyze group differences in the ROM and muscle strength. Analysis of variance with repeated measures was used to analyze the differences between the two groups in muscle activation of each period of the stance phase. Then we calculated Pearson's correlation coefficient to estimate the association between muscle strength, COP displacement, muscle activation and the severity of flatfoot. Results: Subjects with flexible flatfoot is stronger in hallucal abductor/flexor groups than the normal-arched subjects. The muscle activation of abductor hallucis in the terminal stance is significantly higher in subjects with flatfoot. The mediolateral displacement of COP during walking is smaller in flatfooted subjects. There are positive correlations between the severity of flatfoot, strength of hallucal abductor/flexor groups and the activation of abductor hallucis during terminal stance (r=0.43-0.49). There is a weak negative correlation between the mediolateral displacement of COP and severity of flatfoot (r=-0.35). Conclusions: The posture of foot might influence selected muscle activation and COP excursion during gait. The hallucal abductor/flexor groups are stronger and the abductor hallucis muscle is more active in the terminal stance in our subjects with mild flexible flatfoot; this may be explained by overloading the muscle to aid push-off and propulsion of the body weight in these individuals. Additionally, narrower mediolateral COP span, which was weakly negatively correlated to the activation of abductor hallucis, was found in subjects with flatfoot during walking. Clinical Relevance: Abductor hallucis is assicated with COP excursion during gait, and may be highly recruited in subjects with mild flexible flatfoot. These subjects may benefit from training programs to reduce the risk of fatiguing this muscle.

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47

WEI, SHUN-HUA, and 蔚順華. "A mechanical model for swing phase of human gait and quantitative analysis of inertia in B/K prostheses." Thesis, 1988. http://ndltd.ncl.edu.tw/handle/47058456454043854763.

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48

Luan, Wu-fu, and 阮五福. "A three dimensional biomechanical model for swing phase of humwn gait and analytic smiulation of below-knee Amputees." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/57800609681803515653.

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碩士
國立成功大學
醫學工程學系
84
Recently, scholars have used biomechanical model to predict and analyze the dynamics of human motion. Some of them focus on gait analyses that intend to give people better understanding of human walking pattern and the induced joint forces. In order to build a biomechanical model that can predict the gait motion of below-knee amputees, this paper uses seven links to build a three dimensional dynamic model to simulate the swing phase of human gait. The dynamic equations are derived based on Newton- Euler method. Once the motion parameters such as displacement, velocity、and acceleration are measured experimentally,the joint forces of normal subject could be obtained by inverse- dynamic method. These joint forces could then be used as referenced parameters to predict the motion trajectory of below- knee amputees by direct-dynamic method, where some of the parameters, such as the body mass and moment of inertia, are changed to that of amputees, also some constraints are added to limit the mobility of the model to emulate an artificial limb .

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49

Honsová, Kamila. "Vliv fyzioterapie na stabilitu stoje a vybrané klinické parametry u pacientů s roztroušenou sklerózou." Master's thesis, 2008. http://www.nusl.cz/ntk/nusl-290714.

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Diploma thesis "Impact of physiotherapy on stability in stance and selected clinical parameters in Multiple Sclerosis patients" is aimed to study problems of disturbed postural stability in connection with this disorder. Research was made to evaluate the impact of two-month's physiotherapy, based on sensomotor learning, on the balance in stance, gait parameters and related functions. The sample of 6 patients with disability EDSS = 5, age 43 and more than five years course of MS on average, were undergoing a battery of clinical and paraclinical tests. Questionaire method was used for assessing quality of life parameters. Powered by TCPDF (www.tcpdf.org)

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50

Bulánová, Kateřina. "Analýza stoje a chůze s využitím ZEBRIS FDM-T systému u pacientů se skoliózou." Master's thesis, 2016. http://www.nusl.cz/ntk/nusl-345646.

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The thesis deals with the issue of walking and standing in patients with a scoliosis. The theoretical part of this thesis summarizes current knowledge of scoliosis, its classification, etiology, pathogenesis and risk factors of the curve progression. Then the most often changes of the stand and gait stereotype and their main causes are discussed. Goal of the practical part was to identify the difference between particular parameters of gait in an experimental group of patients with scoliosis and a control group of healthy individuals. The examination was performed via the dynamic plantography method using the Zebris FDM-T System. 19 probands with scoliosis aged 8 - 19 and a control group of 19 orthopedically healthy patients in a corresponding age distribution have been selected for the study. The results did not provide any statistically significant difference on a significance level p=0,05. However, there were clear differences between the groups referring to bigger asymmetries in stance and gait stereotype in the scoliosis patients group. Since even in a scientific literature there is a difference in opinion on this issue, more research might be necessary for the exact evaluation of the influence of scoliosis on the stance and gait stereotype.

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Dissertations / Theses on the topic 'Stance phase of gait'

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