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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.
1

Biomechanical analysis of a ballistic throwing task under different loading conditions using non-linear optimisation methods

Tsirakos, Dimitrios Konstantinos January 1998 (has links)
No description available.
2

In vivo mechanical assessment of human elbow kinematics using a six axis parallel mechanism developed in house

Alrashidi, Mohammad January 2011 (has links)
Elbow joint laxity is a problem that normally comes with age; it increases up to critical levels due to rupture or damage to the ligaments of the elbow and affects the stability and capacities of the joint, interfering even with daily activities. This work investigates the kinematics of the elbow through in-vivo experimental measurement. To this end, a platform based on Stewart Platform mechanism was built and used at the bioengineering labs of Brunel University in West London, the UK, to measure the six degrees of freedom of the joint. This thesis aims to develop a method to simulate such motion which could be used for elbow implant design and manufacture. This work contributes to both the basic science of joint movement measurement and to the clinical applications of diagnosing elbow illness. In addition this research presents the preliminary results for a design for elbow implants. Tracking system developed in house was used to measure the degrees of freedom in healthy elbow motion. A pilot study was performed to assess the joint motion and its repeatability. A group of volunteers with normal elbow movement was used to carry out this study. A Stewart Platform mechanism based on the tracking system was used in this study as a non-invasive tool to capture elbow joint motion and track the trajectory and pattern of the motion in three-dimensional space. This thesis aimed to develop a method to simulate the elbow joint motion that could potentially be used for the elbow implants design and there manufacture. The goal of this study was achieved by in vivo measurement of the elbow movement. It was found that the results vary from person to person, but a healthy pattern of motion can be distinguished from an abnormal pattern. To ensure the result, the motion of the right and left hand of each person was compared,allowing the behaviour of the elbow motion to be judged and the results can help surgeons to analyze the motion of the elbow joint and follow up suspicions of abnormal behaviour in the joint or trace any possible joint laxity. Furthermore, the errors involved with the mechanism were calculated and appropriate factors were applied to correct them. As part of this study the manufacturing of medical implants was reviewed and discussed.
3

The design of a new elbow prosthesis

Boddington, Richard John 30 March 2017 (has links)
No description available.
4

The Anatomical Characteristics of a Giant Miocene Amphicyonid (Carnivora) Humerus From Pakistan

Viranta, Suvi, Hussain, S. Taseer, Bernor, Raymond L. 06 May 2004 (has links) (PDF)
A recently discovered distal humerus shows that very large bodied amphicyonids existed in Pakistan in the Early Miocene. Movements on their elbow joint are interpreted to be very similar to those of modern bears. They had powerful front limbs, which were probably used to grasp the prey. Taxonomic affinities of the specimen are also discussed.
5

Arthroplasty of the rheumatoid elbow with special reference to nonconstrained replacement and its complications /

Ljung, Peter. January 1995 (has links)
Thesis--Lund University, 1995.
6

Arthroplasty of the rheumatoid elbow with special reference to nonconstrained replacement and its complications /

Ljung, Peter. January 1995 (has links)
Thesis--Lund University, 1995.
7

Contribution of the anconeus muscle to the elbow kinematics : range of motion of 90° of flexion-extension and pronation-supination

Miguel Andres, Israel January 2016 (has links)
The anconeus, a small triangular muscle positioned on the posterolateral part of the elbow joint, has been the subject of considerable research without a satisfactory conclusion being reached regarding the role it plays during normal elbow kinematics. The aim of this investigation was to elucidate the function of the anconeus muscle and find the relative contribution that it makes to elbow kinematics by examining relative electrical muscle activity and elbow kinematics both before and after anconeus defunctioning carried out using a local anaesthetic (lidocaine). The study was performed through an examination of the myoelectric activity of the representative elbow flexor and extensor muscles (biceps brachii and triceps brachii) and the elbow kinematics and kinetics. Right-handed, healthy volunteers performed elbow flexion-extension and supination-pronation movements in both horizontal and sagittal planes before and after blocking of the anconeus. The kinematics and kinetics of the elbow were assessed using inertial sensors, and muscle electrical activity was recorded using surface electromyography. In the following stage of the study, the anconeus muscle was blocked through an injection of lidocaine and then the flexion-extension and pronation-supination movements were repeated. The relative electrical activity results from the anconeus before blocking clearly indicate that the activity of the muscle was higher during the extension portion of the flexion-extension cycle, suggesting that it behaves as an extensor muscle. However, from the paired sample t-test analysis, it was found that blocking of the anconeus had no effect on the kinematics and kinetics of the elbow, including the angular velocity, net torque, power and net joint work. Moreover, the angular velocity data for the elbow, before and after the blocking for all movements, showed a linear trend with slopes and Pearson's correlations close to unity, indicating no apparent difference on the elbow kinematics. In addition, the relative electrical activity of the biceps and triceps brachii muscles did not alter significantly following blocking of the anconeus. These findings suggest that the anconeus muscle is a relatively weak elbow extensor as it is likely that the small contribution that the anconeus provides during extension before blocking is compensated by the triceps brachii after the anconeus is deactivated. In order to provide additional weight and support to the findings of the experimental study, a computational model of the elbow joint was created in Abaqus CAE with the aim of investigating the contribution of the anconeus during the flexion-extension motion. In particular, the effect on the range of motion and contact area of the elbow joint was investigated both before and after anconeus blocking. The analysis was done in a range of motion of 90°, starting with the elbow extended 30° and ending flexed 120°. The elbow joint model considered cortical bone, trabecular bone, cartilage, collateral ligaments, the anconeus, biceps brachii and triceps brachii. The results of the investigation indicated that the anconeus muscle does not produce a significant change in the range of motion and contact area in the articulation, an outcome that supports the findings of the experimental investigation.
8

Možnosti prevence hyperextenčního traumatu loketních kloubů u brankářek házené / Methods of prevention in hyperextension trauma to the elbow of the handball goalkeeper

Šrámková, Šárka January 2015 (has links)
Title: Methods of prevention in hyperextension trauma to the elbow of the handball goalkeeper. Objectives: The main objective of this thesis is to determine whether the muscle strengthening exercises stabilizers of the elbow affect the stability of the elbow joint and also draw attention to the issue of hyperextension trauma to the elbow joint of the handball goalkeeper. Another objective is to evaluate the possibility of prevention of hyperextension trauma to the elbow joint of the handball goalkeeper. Methods: Rating angular deviations observed in the elbow before and after completing the intervention. Deviations were recorded using a 3D analysis system Qualysis and were processed in software Qualisys Track Manager. Results: Strengthening the dynamic stabilizers of the elbow helps to improve stability of the elbow joint load into hyperextension. Active exercise can be used as a possible prevention of hyperextension trauma to the elbow joint of handball goalkeepers. Keywords: elbow joint, hyperextension trauma, goalkeeper, handball, strengthening
9

Avaliação radiográfica e tomográfica da articulação umerorradioulnar em cães / Radiographic and tomographic study of elbow joint in dogs

Grunkraut, Alessandra Sendyk 18 June 2014 (has links)
A displasia do cotovelo é considerada uma disfunção ou má formação da articulação umerorradioulnar com causas multifatoriais, é a causa mais comum de claudicação de membros torácicos em cães jovens e acomete principalmente cães de raças grandes e gigantes. As alterações da displasia do cotovelo incluem não união do processo ancôneo, fragmentação do processo coronóide medial, osteocondrose da tróclea umeral, incongruência articular e doença articular degenerativa. Esse estudo teve como objetivo apresentar de forma detalhada dados morfológicos e morfométricos da articulação umerorradioulnar de cães de raça definida avaliados por meio de exames clínicos, radiográficos e tomográficos. A amostra de cães dessa pesquisa constituiu-se de 44 cotovelos de cães com idades variadas. Realizou-se a comparação do desempenho de diferentes projeções radiográficas individualmente e sua análise comparativa com o exame tomográfico, mensuração da incongruência radioulnar ao exame tomográfico e posterior comparação à análise qualitativa ao exame radiográfico, cálculo do ângulo da incisura ulnar e sua comparação entre exames radiográfico e tomográfico e verificação da concordância entre avaliadores para as diferentes mensurações realizadas nos exames radiográfico e tomográfico. Para análise dessas informações, o coeficiente kappa, correlação interclasse e testes Fischer e McNemar foram realizados. Constatou-se que o desempenho individual de cada projeção radiográfica teve pobre concordância com o exame tomográfico sugerindo-se a realização de mais de duas projeções radiográficas; não houve concordância entre os três observadores para as mensurações do ângulo da incisura ulnar ao exame radiográfico e tomográfico. Porém houve boa/moderada concordância para mensuração da incongruência radioulnar no plano sagital entre os observadores. Concluiu-se que nenhuma das cinco incidências radiográficas foi superior à outras para análise radiográfica, uma vez que cada projeção apresentou melhor identificação de um compartimento do cotovelo; medidas ao exame tomográfico para incongruência radioulnar não apresentam reprodutibilidade no corte dorsal, no corte sagital apresentaram boa e moderada concordância entre os observadores e que a mensuração do ângulo da incisura ulnar não apresentou repetibilidade ao exame radiográfico e reprodutibilidade ao exame tomográfico. / Elbow dysplasia is considered a dysfunction or malformation of the elbow joint with multifactorial causes and is the most common cause of thoracic limb lameness in young dogs and mainly affecting large and giant breeds. Elbow dysplasia disease include ununited anconeal process, fragmented medial coronoid process, osteochondrosis of humeral trochlea, articular incongruity and degenerative joint disease. The aim of this study was to present detailed morphologic and morphometric aspects of the elbow joint in Labrador retriever and Australian shepherd dog in clinical and correlate with radiographic and tomographic (CT) exam. Interobserver variation for articular incongruity measurements by CT, comparative analysis in the radiographic exam, angle in ulnar notch and its comparative analysis between radiographic and tomographic agreement examination in 44 elbow of dogs with different ages were evaluated. The statistics analyses included the kappa coefficient and interclass correlation and Fischers test and McNemars test. It was evidenced that individual performance of each radiographic incidence had poor agreement with the tomographic exam, suggesting that the accomplishment of more than two radiograph views are needed. There was no agreement between the three evaluators in the ulnar notch angle at radiographic and tomographic exams. However, there was good/moderate agreement for articular incongruity measurement in the sagittal plane between evaluators. It was possible to conclude that none of the five radiographic incidences was better than the others for radiographic analysis because each incidence had a better identification of a particular elbow compartment; measurements at the tomographic exam to evaluate radioulnar incongruity had no reproductiveness in the dorsal plane, but in sagittal plan had a good/moderate agreement between observers and the angle in ulnar notch presented no repeatability at radiographic exam and no reproductiveness at tomographic exam.
10

Morphologische und klinische Untersuchungen zur experimentellen Denervation des Ellbogengelenks beim Hund

Fischer, Jenny 30 May 2012 (has links) (PDF)
Die Osteoarthrose (OA) des Ellbogengelenks ist eine der wichtigsten Gelenkerkrankungen des Hundes, die sich aufgrund erblich bedingter Fehlstellung der Gelenke sekundär häufig schon bei sehr jungen Hunden entwickelt und zu einer verminderten Lebensqualität der Tiere führt. Im Laufe der Erkrankung kommt es zu einer Schädigung des Gelenkknorpels, der an Elastizität und Spannkraft verliert und seine Funktion, nicht mehr ausüben kann. Eine Ablösung von Knorpelfragmenten und Entzündungen im Gelenk können die Zerstörung des Gelenkknorpels beschleunigen. Die OA ist nicht heilbar. Das Therapieziel ist eine möglichst vollständige Schmerzreduktion und die Verbesserung der Lebensqualität. Eine chirurgische Denervation ist im Ellbogengelenk des Hundes ohne Traumatisierung anatomischer Strukturen nicht möglich. Ziel der vorliegenden Arbeit war es, erstmalig einen experimentellen Ansatz zur chemischen Denervation sensibler Gelenkafferenzen im Ellbogengelenk beim Beagle mit dem Neurotoxin OX7-Saporin durchzuführen. Zusätzlich wurden Substanzen aus der Humanmedizin zur Schmerzreduktion und symptomatischen Therapie der OA am Hund erprobt und der Therapieerfolg evaluiert. Im Rahmen eines Therapieversuches in der Klinik für Kleintiere der Universität Leipzig wurde bei zwei, an OA erkrankten Hunden Capsaicin einmalig intraartikulär injiziert. Der erste Hund erhielt intraartikulär 250 mg Capsaicin. Dieser Patient zeigte Nebenwirkungen in Form einer Herz- und Atemfrequenzerhöhung, starker Schmerzhaftigkeit und neurologischen Symptomen. Der zweite Hund wurde mit 83 mg Capsaicin behandelt und zeigte keine Nebenwirkungen. Sowohl die Bewertung der Besitzer als auch die orthopädische Untersuchung ergaben keine Verbesserung der Lahmheit. Vier kranken Hunden wurde ebenfalls im Rahmen eines Therapieversuches Botox (Botulinumtoxin A) intraartikulär einmalig injiziert. Drei Hunde wurden mit 50 Einheiten, ein Hund mit 100 Einheiten Botox behandelt. Die Applikation von Capsaicin und Botox führten zu keiner Verbesserung der Symptomatik. In der Humanmedizin ist die Schmerzbehandlung mit Capsaicin und Botox erfolgreich. Deshalb sollten diese Therapieansätze auch für die Anwendung beim Hund weiter optimiert werden. Das Neurotoxin OX7-Saporin wurde in einer Dosierung von 100 µg erstmalig in das Ellbogengelenk von drei Beagle-Hündinnen appliziert, um eine sensible Denervation des Gelenkes zu erreichen. Der retrograde Transport des Ribosomen-inaktivierenden Proteins in die Perikarya der Spinalganglienzellen, die das Ellbogengelenk sensibel innervieren, sollte eine selektive Zerstörung der Neurone durch das Neurotoxin bewirken. Der retrograde Tracer Fluoro-Gold wurde, zur Kontrolle der Wirkung des Neurotoxins, nach einer Wartezeit von 15 Tagen intraartikulär in das linke und das rechte Ellbogengelenk appliziert. Fluoro-Gold kann ausschließlich von intakten Nervenfasern transportiert werden. Die Ganglien C4 - Th3 wurden bilateral zur histologischen Auswertung entnommen und in Paraffin eingebettet. Zur Bestimmung der Gesamtneuronenanzahl wurden alle Neurone in jedem dritten Schnitt eines Ganglions gezählt. Die Summe dieser Nervenzellen ergab die Gesamtneuronenanzahl eines Ganglions. Die Einlagerung von Lipofuszin führte zu einer starken Autofluoreszenz im Zytoplasma der Neuronen. Alle Schnitte wurden mit Sudan-Schwarz gefärbt, um die Autofluoreszenz von der retrograden FG-Markierung zu unterscheiden. Die FG-Markierung konnte nur in den Ganglien C6 und Th1 im Zytoplasma sehr weniger Neuronen dokumentiert werden. Der histologische Nachweis einer Neurodegeneration nach Applikation des Neurotoxins OX7-Saporin in das linke Ellbogengelenk war negativ. In den untersuchten Spinalganglien wurden intakte Nervenzellen nachgewiesen. Auch die bilaterale intraartikuläre Injektion des retrograden Tracers FG war nicht erfolgreich. Aus den Ergebnissen dieser experimentellen Ansätze wird zusammenfassend geschlussfolgert: Ø Vor der Durchführung zukünftiger experimenteller Untersuchungen beim Hund muss die optimale Konzentration und die Wartezeit für das Neurotoxins OX7-Saporin ermittelt werden. Ø Die Rezeptoren für OX7-Saporin müssen an den Nervenzellen des Hundes zweifelsfrei nachgewiesen werden, bevor das Neurotoxin im caninen Tiermodell eingesetzt werden kann. Ø Die optimale Konzentration des Fluoreszenzfarbstoffes FG für intraartikuläre Injektionen und dessen retrograde Transportgeschwindigkeit beim Hund müssen ermittelt werden, bevor dieser Tracer wieder im Tierexperiment eingesetzt werden kann. Ø FG wurde als 1,8%ige Lösung in das Ellbogengelenk beim Beagle appliziert. Diese Konzentration war wahrscheinlich zu gering, um eine retrograde Markierung der sensiblen Neurone in den entsprechenden Spinalganglienzellen nachzuweisen. Ø Die intraartikuläre Applikation des Neurotoxins OX7-Saporin führte nicht zur selektiven Neurodegeneration. Eine Aussage zur Schmerzausschaltung und symptomatischen Therapie der OA des Hundes mit OX7-Saporin ist deshalb nicht möglich.

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