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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Strategies and Adaptations Seen with Unilateral Lower Limb Weighting during Level Ground Walking and Obstacle Clearance Tasks

DeRochie, Marc 14 January 2010 (has links)
Abstract: Previous lower limb weighting studies have placed a load on the legs bilaterally and tested different placement locations. It was previously determined that kinematic changes occur with greater masses and at joints proximal to weight placement [1]. Other studies have determined that these changes exist for a short adaptation period before parameters revert to a steady state [2]. Tasks that require voluntary gait modifications such as obstacle clearance have also been performed with lower leg bilateral weight addition [4]. In cases of normal obstacle clearance increased flexion at all three joints in the lower limb is needed to safely traverse the obstacle [3]. The goal of this study was to investigate joint kinematics and kinetics of unilaterally weighted participants using level ground force platform collection techniques, rather than a treadmill. It was hoped that this would allow for new insight into the adaptation periods and strategic motor pattern changes seen at the ankle, knee and hip. Kinematic and force platform data were collected on two groups of 10 healthy male subjects. Group 1 (mean age = 23years, mean weight = 82.181kg, mean height = 1.798m) was a normal walking group and group 2 (mean age = 24.8years, mean weight = 79.901kg, mean height = 1.773m) was an obstacle clearance group. Both groups participated in 20 trials each of three different conditions; normal, weighted and weight off using a 2.27kg limb mass attached just proximal to the right maleoli markers. A repeated-measures two-way ANOVA was carried out on relevant variables in order to determine statistical significance. Weight addition and removal affected the kinematics and kinetics of the normal walking and obstacle clearance groups. This effect was more prominent in the normal walking group. If changes were seen, trials 1 through 3 were the locations showing a quick adaptation followed by a leveling off back to a new steady state in later trials. Participants in the normal walking group chose to utilize the hip joint in order to control for weight addition and removal. Kinematically, changes in the hip joint angle occurred at all instances analyzed throughout the gait cycle with this effect being more prominent in the weight off condition. In conjunction with this, the hip joint energy generation increased during all phases of the gait cycle while the ankle and knee joints either decreased energy generation or increased energy absorption. In the obstacle group, participants also chose to increase flexion at the hip joint. However, the ankle joint also had either decreased plantarflexion or increased dorsiflexion at all the instances analyzed during the gait cycle. However, joint energy generation increases at these joints were only found during stance and at heel contact. The toe obstacle clearance values also showed a marked increase in trial 1 for the weighted condition which demonstrates a voluntary gait modification made by participants to safely traverse the obstacle that was quickly adapted for. Overall, the results found by previous studies using treadmill collection techniques were still seen in overground force platform data but they were not as robust. References: 1.Martin PE et al. J Biomech. 1990; 23(6):529-536. 2.Noble et al. Exp Brain Res. 2006; 169: 482-495. 3.Patla AE et al. Exp Brain Res. 1995; 196: 499-504. 4.Reid MJ et al. Neurosci Res Comm. 2001; 29(2): 79-87.
52

Development of Conceptual and Process Models of Growing Pains: A Mixed-Method Research Design

Visram, Faizah 06 August 2009 (has links)
Despite being a common childhood complaint there is little research on growing pains. Existing research is inconsistent with regard to sample selection and prevalence rates. There are only two English language intervention studies, and with the exception of associations noted in prevalence research, there has been no systematic research on the potential impact of growing pains on daily activities. Lack of a universal definition of growing pains poses difficulty for both diagnosis and research. The purposes of the current investigation were to propose a definition of growing pains grounded in literature and clinical practice, to develop a conceptual model of growing pains, and to understand childrens experiences with growing pains. A mixed-method research program involved four phases. In phase I, a survey of physicians indicated the following definition of growing pains: Intermittent pain of unknown etiology, occurring nocturnally in the lower limbs. Features that may occur in some cases, but not part of the definition, include arm pain and daytime pain. In phase II, non-parametric statistical analyses of child, familial, and environmental variables in a rheumatology clinic database were conducted to determine potential risk factors for growing pains. Logistic regression modeling indicated an association between growing pains and maternal illness or rash during the pregnancy, maternal smoking during the pregnancy, delayed pull to standing (i.e., greater than age 10 months), and family histories of back pain and arthritis. Potential mechanisms for these empirical associations are explored. In phase III, qualitative interviews with children were conducted to develop a grounded theory of how children process their experiences. Children engaged in a process of evaluating their current and past experiences of growing pains to determine how to manage specific pain episodes. Their evaluation was influenced by how they understood their pain which in turn was influenced by their intrapersonal and interpersonal experiences. Phase IV integrated results and existing literature to develop a conceptual model of growing pains which outlines characteristic features, predisposing factors, triggers, alleviating actions, and associated psychosocial features. Implications of the process theory and the conceptual model of growing pains with regard to clinical practice and future research are discussed.
53

System design for lower limb rehabilitation : upstairs and downstairs trainings

Liao, Yin-ling 12 August 2010 (has links)
The study is to propose a novel design for the lower limb rehabilitation system through the motion training of stepping upward or downward. A main goal of this design is to constrain the system dimension to a small value for home use purpose. It is also desired that the functioning of system is automatic that the direction of stepping upward or downward can be changed arbitrarily in the training process. The TRIZ theory, which offers a systematic thinking process for problem solving, is adopted in this study to construct the first step of conceptual design. From the theory, the problems of system design is mainly to deal with three issues, which are the spatial analysis and optimization, motion conversion design for ladder, and the motion control of ladder. The spatial analysis is to investigate the optimal trajectory of ladder motion that the total space of the system can be minimized. It is done by assuming a specific geometrical property of ladder trajectory and solving the optimization problem through the parameter optimization. The motion conversion design is to invent an approach to change the configuration of ladder from either open-to-close or close-to-open status. To do so, a small section of ladder trajectory is asked to be flexible and a mechanism to trigger the configuration change is proposed. The motion control is to maintain the user located in an almost same location while the training is preceded. In this study, the PID control scheme is adopted to examine whether the control goal can be properly achieved. This study reveals that a proper design can be obtained through the specific process of problem solving. The system is shown to function well when the above three issues are solved by the proposed schemes.
54

Mechanical Properties of Dynamic Energy Return Prosthetic Feet

Haberman, Andrea 16 April 2008 (has links)
The long-term goal of this study is to improve the ability of designers and prosthetists to match the mechanical characteristics of prosthetic feet to patient specific parameters, including, needs, abilities and biomechanical characteristics. While patient measures of performance are well developed, there is a need to develop a practical method by which non-linear and time-dependent mechanical properties of the prosthetic component can be measured. In this study, testing methodologies were developed that separately evaluated the elastic and time-dependent properties. Three styles of feet were tested to span the range of designs of interest: a standard solid ankle cushioned heel (SACH) foot, two energy return feet for active users and a new prosthetic foot designed to provide partial energy return. The first testing regime involved mechanically characterizing prostheses under conditions similar to gait. The heels and toes of four sample feet were loaded to peak forces based on their design mass at a series of angles and forces that the prosthetic system would go through during the gait cycle, based on the waveform in ISO 22675. Tangential stiffnesses of the samples were determined using numerical differentiation. The force-displacement responses of prosthetic feet reflect increasing stiffnesses with increasing loads and a decreasing pylon angle. Key features reflecting foot design are: the relative stiffness of the heel and toe and the displacement gap at midstance. Stable feet tend to exhibit lower heel stiffnesses and higher toe stiffnesses, whereas dynamics energy return (DER) feet tend to exhibit higher heel stiffnesses and lower toe stiffnesses. The differences in heel and toe loading at midstance suggest that DER feet can aid in the transition from heel to toe, providing a smooth rollover whereas SACH feet provide greater stability. A second testing regime examined the time-dependent properties of the heel and toe. A three-parameter reduced relaxation response of the form was able to capture the force-relaxation characteristics with RMS differences ranging from 0.0006 to 0.0119. In this model, A is the initial decay, B is the decay coefficient, a linear decay term, and τ is a time constant. While the model is practical for comparing various prostheses at a single load level, a fully non-linear model is required to model the time-dependent response at all loading levels. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2008-04-16 11:27:02.51 / Otto Bock® Dupont Niagara Prothetics and Orthotics International Health Technology Exchange (HTX) Ontario Centres of Excellence
55

An analysis of the different spike attack arm swings used in elite levels of men's volleyball

Plawinski, Marek Pawel 18 July 2008 (has links)
Objective As part of this work, two preliminary studies were conducted that identified three possible swings used at the elite level of volleyball and the resulting ball velocities created using these swings. Therefore, the purpose of this work was to explore the kinematic aspects of the different spike attack arm swings (straight ahead (SA), cross body (CB) and outside (OS)) where each different swing was broken down into its constituent parts. Methods Six elite-level varsity players participated in this study. A motion tracking system was used to collect motion data which was used to calculate the kinematics of the upper arm during each of the swing types. A number of minimums and maximums were then calculated including maximum hand speed. To compare means between swings one-way ANOVA’s were used. Results Few differences were found between the swing types. The only difference seen between the SA CB swings was a more pronounced wrist flexion during the CB swing. It is possible that this helped propel the ball across the body during the CB. The OS swings differed from the CB and SA swings in that the OS was less horizontally adducted and there was a more pronounced external rotation during CB than during OS. These differences are likely to be responsible for the ball being hit away from the midline of the body during the OS swing. Typically, the hand speed results agreed with those of the study done previously concerning resulting ball speeds when these swings were employed. Conclusions Between the SA, CB and OS swing types, only the OS was consistantly different throughout the three studies. It is recommended that future studies attempt to examine the whole body during these types of swings. Also, it appears that elite-level players may be quite different kinematically, and each one should be treated as a separate case in a training situation. The findings of these studies may help coaches, trainers and athletes develop better training, injury prevention and rehabilitation programs in the sport. / Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2008-07-16 12:10:06.42
56

Stair Negotiation in an older adult population: Analysis of the lower limb

Reid, Samantha M 25 September 2010 (has links)
Stair negotiation has been identified by older adults as one of the most challenging locomotor tasks, one that is associated with a high risk for falls and serious injury. Currently lacking is a comprehensive understanding of the lower limb during stair negotiation in an older adult population. It has been identified that more research is needed to determine key determinants of difficulty and safety on stairs. The objective of this thesis was to investigate lower limb kinematics and kinetics during stair negotiation and evaluate the impact of handrail use on stair ambulation in young adults, older adults, and older adults with a fear of falling (FOF). The four studies that make up this dissertation provide a detailed picture of the lower limb joint kinematics and kinetics during stair ambulation, as well as provide insight into the role of handrail use and FOF in performance of stair negotiation. Specifically, in the first study principal component analysis (PCA) was used, of the scores generated from the PCA models four principal component (PC) scores were identified that could be used to correctly classify 95% of young and older adults. The second study provided a comprehensive data set of lower limb joint kinematics and kinetics during stair negotiation. The third study identified comparable centre of pressure velocities (VCOP) between young adults and older adults during stair negotiation with and without a handrail. Whereas older adults with FOF demonstrated reduced VCOP during stair negotiation without a handrail and further reduced VCOP when using the handrail. Furthermore, no significant difference in lower limb moments during stair negotiation with and without a handrail were found in older adults, as was similar for older adults with FOF. However, a gait assessment revealed that older adults with FOF demonstrated differences from ‘normal’ gait patterns during stair negotiation with and without a handrail. These studies provide a comprehensive normative dataset of the lower limb joint kinematics and kinetics during stair negotiation, as well as provide insight into the role of handrail use and fear of falling in performance of stair ambulation. It is important to appreciate the nature and extent of normal age-related adaption and compensatory strategies to identify unique patterns of movement due to the superimposition of pathology. / Thesis (Ph.D, Kinesiology & Health Studies) -- Queen's University, 2010-09-24 14:50:22.242
57

Ankylosaur (Dinosauria, Ankylosauria) foot morphology and an assessment of the function of the limbs and feet

Sissons, Robin L. Unknown Date
No description available.
58

Imaging and image processing in the trans-femoral prosthetics

Douglas, Tania January 1998 (has links)
No description available.
59

Ankylosaur (Dinosauria, Ankylosauria) foot morphology and an assessment of the function of the limbs and feet

Sissons, Robin L. 11 1900 (has links)
Morphology and function of ankylosaur dinosaur limbs are explored and analyzed using comparative morphology and finite element analysis. Reconstruction of the forelimb and posture of Pinacosaurus grangeri matches well with trackways attributed to ankylosaurs. A flexed humerus angled away from the body, perpendicular radius and ulna, and upright metacarpus forming an arch proximally result in a crescent configuration of the manus, and a semi-supinated posture relative to the main axis of the body. The ankylosaurid metatarsus has a twisted proximal articular surface, metatarsals being optimally adapted for bearing weight at increasing angles, from medial to lateral. Metatarsal counts of Thyreophorans and other basal ornithischians do not match well with currently accepted phylogeny of these taxa, indicating that a revised phylogeny should be considered. Finite element analysis results, the twisted proximal articular surface, and other morphological features support a rolling motion in the foot while pushing off in locomotion. This is perhaps an adaptation to cope with the wide hips of ankylosaurids, bringing the pes closer to the midline of the animal during locomotion to increase maneuverability. / Systematics and Evolution
60

Participation restrictions and vocational needs amongst persons with a lower limb amputation in Cape Town, South Africa

Wing, Yu Tak January 2017 (has links)
Masters of Science - Msc (Physiotherapy) / Vocational rehabilitation relates to rehabilitating a person with an amputation back into actively participating in society. Although vocational rehabilitation is important, before it can be implemented, the participation restrictions should be identified. Even though lower limb amputation surgery is commonly performed in South Africa, and given the high unemployment rate in the country, no research has been done into the participation restrictions and vocational needs of a person with a unilateral lower limb amputation in the Western Cape. The aim of this study was to determine and explore the participation restrictions and vocational rehabilitation needs in terms of hobbies, sport activities, employment and employment needs of persons with a unilateral lower limb amputation (LLA) in the Western Cape. The objectives were to: 1) Determine the participation restrictions of persons with a unilateral LLA in the Western Cape. 2) To explore the vocational rehabilitation needs of persons with a lower limb amputation. A mixed methods approach, and an explanatory sequential design was used in this study. The study was conducted in two phases. The first phase utilised a quantitative approach and the WHODAS 2.0 was used as the instrument to collect data. The second phase aimed to explain the data collected in the first phase in more depth, and semi-structured telephonic interviews were utilized to collect the qualitative data. The study was set in the Cape Metropole region of the Western Cape. Participants were recruited from Tygerberg Tertiary Hospital and a private sub-acute rehabilitation centre. In the quantitative (first) phase of the study, 50 participants were conveniently recruited to participate. In the second phase eight participants were purposefully selected from the pool of 50 participants from the first phase of the study who consented to participate in the second phase. Quantitative data was analysed using SPSS vs. 22 and analysed for descriptive and inferential statistics. Qualitative data has been analysed using Creswell's seven step process of thematic analysis. Ethical clearance has been obtained from the University of the Western Cape, permission to access patients' details has been obtained from Tygerberg Tertiary Hospital and private sub-acute rehabilitation centre. Written informed consent as well as permission for audio recording during the telephonic interview was obtained.

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