Tesi sul tema "Tendon"
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1
Bouguer-Diquelou, Anne. "Rupture sous-cutanee du tendon d'achille (tendon calcaneen)". Nantes, 1989. http://www.theses.fr/1989NANT051M.
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2
Yuen, Man-hon. "Biomechanical analysis of tendon repair method in obliquely lacerated tendon /". View the Table of Contents & Abstract, 2005. http://sunzi.lib.hku.hk/hkuto/record/B31495539.
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3
張劍偉 e Kim-wai Cheung. "Biomechanical analysis of tendon repair method in partially lacerated tendon". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40738644.
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4
Yuen, Man-hon, e 阮文瀚. "Biomechanical analysis of tendon repair method in obliquely lacerated tendon". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B45010559.
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Breidenbach, Andrew P. "Translating Mechanisms of Tendon Development to Improve Adult Tendon Repair". University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1406809080.
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Cheung, Kim-wai. "Biomechanical analysis of tendon repair method in partially lacerated tendon". Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B40738644.
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7
Choi, Rachel Koeun. "Tendon properties: Differences between tendon types and why these occur". Thesis, The University of Sydney, 2019. http://hdl.handle.net/2123/20770.
Testo completoAbstract (sommario):
Tendon disorders are hugely burdensome to individuals, costly on a societal level, and are being compounded by the increasingly ageing population. These chronic and often disabling conditions are poorly understood and lacking in an effective long-term treatment. Recently, attempts to elucidate the underlying mechanisms of tendon diseases in order to improve their prognosis have arrived at a key hypothesis: it is posited that the various tendons found throughout the body have unique properties, unique responses to disease-causing stimuli, and in turn therefore, different responses to the therapies being applied. It is possible this is why individual therapies are simultaneously effective in specific patient groups, and disappointingly ineffective in others. The theme of distinct tendon phenotypes is central to this thesis. This body of work explores the hypothesis that functionally distinct tendons respond differently to changes in their loading environment, first by assessing properties developed in vivo in response to a surgically-induced injury of an equine tendon, and then the properties of ovine tendons developed in response to their distinct in vivo functions. It continues by then developing and applying in vitro loading environments, where more precisely controlled loading is used to understand how tendons with highly energy-storing functions may differ from simply positional tendons, at rest and under various loading conditions. The scope of the results span multiple levels, from cells and tissues, to the functional mechanical properties of multiple tendons and disease phenotypes, in order to better understand how these influence each other. This broad approach helps to try and unify work which has previously been isolated by discipline, and more accurately contextualise previous and future work to better understand tendon phenotypes. The key findings of this thesis are: A focal tendon injury in the horse's energy-storing superficial digital exor tendon disrupted healthy relationships (e.g. biomechanics-glycosaminoglycans), and caused widespread increases in chondroitin/dermatan sulfate glycosaminoglycan levels, which were partially responsible for the concomitant reductions in modulus and ultimate tensile strength. A subsequent study of three functionally distinct ovine tendon types showed higher biomechanical properties of the medial branch of the common digital extensor tendon, a positional tendon, when compared to its energy-storing counterparts, and distinct responses to stress-deprivation, with regards to loss of glycosaminoglycans and biomechanical properties. The underpinning gene expression and immunohistochemistry results suggest that despite broad similarities between the tendon types, differences also exist at baseline and in response to stress-deprivation. When cyclic loading ± compression loading were applied identically to those functionally distinct ovine tendons for 10 days, there was a convergence between the tendons in terms of gene expression and histological appearances, but not biochemical properties. Together, these results show there are differences between tendon types in baseline phenotype and mechanical properties and their response to perturbations in normal loading environments. By improving our understanding of the heterogeneity of tendons found throughout the body and their unique responses, this thesis takes a step along the pathway towards more targeted treatment and improved outcomes for tendon disorders.
8
Potts, Geoffrey. "Biomechanic analysis of 'heavy-load eccentric calf muscle' exercise used in the rehabilitation of achilles tendinosis a dissertation submitted in partial fulfilment for the degree of Master of Health Science, Auckland University of Technology, January 2005". Full thesis. Abstract, 2005. http://puka2.aut.ac.nz/ait/theses/PottsG.pdf.
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9
Blomgran, Parmis. "Inflammation and tendon healing". Doctoral thesis, Linköpings universitet, Avdelningen för Kirurgi, Ortopedi och Onkologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-142349.
Testo completoAbstract (sommario):
Tendons heal through three different overlapping phases; the inflammatory, proliferative and remodeling phase. Many studies have investigated what factors influence healing of tendons. However, little was known about inflammation and the immune cells present during Achilles tendon healing by the time this thesis started. We developed a flow cytometry method for our rat model of tendon healing, which enabled us to study different leukocyte subpopulations during Achilles tendon healing. The general aim of this thesis was to understand more about inflammation and the immune cell populations present during tendon healing and how the immune cell composition changes during normal tendon healing. Moreover, we investigated how different factors that are known to influence tendon healing affected the composition of the immune cell population. First, we described the immune cells during the time course of tendon healing focusing on different subpopulations of macrophages and T cells. Then, we studied how these cells were influenced by reduced mechanical loading. Mechanical loading prolonged the presence of M1 macrophages and delayed the switch to regulatory T cells and M2 macrophages compared to reduced mechanical loading. Next, the effect of nonsteroidal anti-inflammatory drugs (NSAIDs) on the leukocyte composition revealed that, even though NSAIDs influence the mechanical properties of healing tendon, this effect was not mediated via changes in the leukocyte sub-populations during early and mid-time tendon healing. Further, the effect of corticosteroids during the inflammatory and remodeling phases of tendon healing was an improved healing of tendons and a reduction of CD8a T cells when corticosteroid was administered after the inflammatory phase. Lastly, we investigated if impairment of tendon healing by NSAIDs was related to mechanotransduction or microdamage during mechanical loading and showed that NSAIDs impair tendon healing by reducing the response to microdamage. In conclusion, these studies show that inflammation plays an important role during Achilles tendon healing, and factors that influence healing can also alter the presence or polarization of immune cell populations.
10
Grant, Tyler M. "Microstructural deformation of tendon". Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:0ad70415-af7a-4b97-a93a-d17a73d8ff44.
Testo completoAbstract (sommario):
Tendon disorders are painful, disabling, and a major healthcare problem, with millions of people affected by tendon injuries each year. Current treatment strategies are inadequate and knowledge of the underlying mechanobiological mechanisms is required to develop novel therapies. Although the tissue–level properties of tendon are well–documented there remains a lack of understanding of the deformation mechanisms of this complex tissue. Therefore, the aim of this thesis is to characterize the microstructural deformation of tendon through biological imaging, mechanical testing, and computational modeling. Emphasis is placed on the structure and function of elastic fibers in tendon, whose role is poorly understood. First, histology, immunohistochemistry, and multiphoton microscopy are used to characterize the organization of elastic fibers in healthy and damaged tendon providing detailed microstructural information on their morphology and location for the first time. Elastic fibers are found to have a sparse distribution in the extracellular matrix, but are highly concentrated in the endotenon sheath and pericellular matrix. Moreover, damaged specimens are found to have a severely disrupted elastic fiber network. Elastic fibers likely contribute to fascicular deformation mechanisms and the micromechanical environment of tenocytes, which are expected to be disrupted in damaged tendon. Second, mechanical testing and enzyme treatments are used to analyze the mechanical contribution of elastic fibers to tendon. Elastase is found to significantly affect the mechanical properties of the tissue and remove the elastin component of both tendon and a control collagen–elastin biomaterial. However, elastase is also found to degrade non–elastin structural molecules that may contribute to tendon mechanics. The mechanical changes associated with the elastase treatment suggest that elastic fibers do not contribute to the elastic recoil of tendon as previously hypothesized. Third, multiphoton microscopy in combination with a novel microtensile testing machine is used to observe the deformation of collagen fibrils and tenocytes in tissue exposed to load. Tissue displacement is consistent with a helical arrangement of fibrils and nuclei experience significant elongation under physiological conditions. These results suggest that a helical arrangement of fibrils is responsible for the nonlinear stress–strain response of tendon and that nuclei are prime candidates for sensing mechanical forces in tendon. Finally, computation modeling and structural imaging are used to generate a microstructural finite element model of tendon. A helical model with embedded pericellular matrix is able to reproduce the stress–strain response and cell–level deformation of the tissue. The pericellular matrix is found to amplify mechanical forces exposed to cells, which is required to initiate mechanobiological stimulation of tenocytes under physiological conditions. Therefore, the structure and composition of the PCM during health and disease is expected to significantly affect mechanobiological mechanisms of tendon. The work presented in this thesis has used new experimental methods to provide novel insight into the structure, function, and deformation mechanisms of tendon. The techniques and concepts developed are widely applicable to the study of collagenous tissues in health and disease. In particular, observations regarding the pericellular matrix may lead to the development of new tissue–engineered and pharmacological strategies for the treatment of tendon disorders.
11
Picaut, Lise. "Synthèse d'un tendon artificiel". Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066265/document.
Testo completoAbstract (sommario):
Le tendon est un tissu conjonctif fibreux qui transmet les forces du muscle à l'os. Il a une structure hiérarchique formée de faisceaux et de fibrilles de collagène de type I orientées parallèlement à son axe. Leurs propriétés structurales confèrent aux tendons une flexibilité et une résistance à la traction élevées. Cependant, soumis à des sollicitations répétées, les tendons peuvent se déchirer et même rompre, ce qui peut rendre nécessaire Une intervention chirurgicale. Plusieurs stratégies sont en cours de développement comme les autogreffes, les tendons décellularisés ou les fibres synthétiques tressées. Cependant, aucun de ces matériaux ne répond parfaitement au cahier des charges de l'ingénierie tissulaire (cytocompatibilitité, propriétés mécaniques etc). L'objectif de cette thèse est donc de produire par extrusion et dans des conditions physiologiques une matrice de collagène qui imite le tendon. Tout d'abord, nous avons étudié les instabilités d’extrusion d’un système modèle (alginate de sodium), choisi pour ses propriétés rhéologiques proches du collagène. A partir de cette étude, nous avons ensuite produit des fils de collagène dense ou de mélanges collagène/alginate de diamètre de l’ordre de 500 µm conduisant à l’obtention de structures alignées selon l'axe du fil. Les conditions physico-chimiques ont été sélectionnées afin d'obtenir des fils homogènes avec les meilleures propriétés mécaniques. Enfin, ces fils ont été mis in vitro en contact avec des cellules souches mésenchymateuses. Celles-ci colonisent nos matrices et expriment les différents gènes caractéristiques du tendon, ce qui suggère qu’elles se différencient en cellules tendineusesTendon is a fibrous connective tissue, which transmits forces from muscle to bone. It is mainly composed of collagen I fibrils and fascicles aligned along its axis. Moreover, collagen fascicles exhibit a helical “crimp” which acts as a natural shock-absorber and may play a role in elastic recoil. Due to this hierarchical structure, tendons present both flexibility and a high tensile strength over a wide load range. When an injured tendon is severely ruptured, a heavy surgical procedure is required. To overcome this issue, several strategies have already been developed as autografts, decellularized tendons, braided synthetic fibers. However, none of these materials fully meets chemical, mechanical and cytocompatibility requirements. The aim of this thesis is to produce a collagen matrix which mimics tendon by extrusion under physiological conditions. First, using alginate solutions as a model system for their similar rheological properties, we performed an extensive study of the helical extrusion instability which hinders the formation of regular threads. Based on this work, we then produced micrometric threads of dense collagen or mixtures of collagen and alginate which exhibit structures aligned along the thread axis. The physico-chemical conditions are chosen in order to obtain homogeneous threads with optimized mechanical properties. Finally, mesenchymal stem cells are seeded in vitro on collagen based threads. They colonize our matrices and express characteristic genes which suggests that they differentiate into tendon-like cells
12
Picaut, Lise. "Synthèse d'un tendon artificiel". Electronic Thesis or Diss., Paris 6, 2017. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2017PA066265.pdf.
Testo completoAbstract (sommario):
Le tendon est un tissu conjonctif fibreux qui transmet les forces du muscle à l'os. Il a une structure hiérarchique formée de faisceaux et de fibrilles de collagène de type I orientées parallèlement à son axe. Leurs propriétés structurales confèrent aux tendons une flexibilité et une résistance à la traction élevées. Cependant, soumis à des sollicitations répétées, les tendons peuvent se déchirer et même rompre, ce qui peut rendre nécessaire Une intervention chirurgicale. Plusieurs stratégies sont en cours de développement comme les autogreffes, les tendons décellularisés ou les fibres synthétiques tressées. Cependant, aucun de ces matériaux ne répond parfaitement au cahier des charges de l'ingénierie tissulaire (cytocompatibilitité, propriétés mécaniques etc). L'objectif de cette thèse est donc de produire par extrusion et dans des conditions physiologiques une matrice de collagène qui imite le tendon. Tout d'abord, nous avons étudié les instabilités d’extrusion d’un système modèle (alginate de sodium), choisi pour ses propriétés rhéologiques proches du collagène. A partir de cette étude, nous avons ensuite produit des fils de collagène dense ou de mélanges collagène/alginate de diamètre de l’ordre de 500 µm conduisant à l’obtention de structures alignées selon l'axe du fil. Les conditions physico-chimiques ont été sélectionnées afin d'obtenir des fils homogènes avec les meilleures propriétés mécaniques. Enfin, ces fils ont été mis in vitro en contact avec des cellules souches mésenchymateuses. Celles-ci colonisent nos matrices et expriment les différents gènes caractéristiques du tendon, ce qui suggère qu’elles se différencient en cellules tendineusesTendon is a fibrous connective tissue, which transmits forces from muscle to bone. It is mainly composed of collagen I fibrils and fascicles aligned along its axis. Moreover, collagen fascicles exhibit a helical “crimp” which acts as a natural shock-absorber and may play a role in elastic recoil. Due to this hierarchical structure, tendons present both flexibility and a high tensile strength over a wide load range. When an injured tendon is severely ruptured, a heavy surgical procedure is required. To overcome this issue, several strategies have already been developed as autografts, decellularized tendons, braided synthetic fibers. However, none of these materials fully meets chemical, mechanical and cytocompatibility requirements. The aim of this thesis is to produce a collagen matrix which mimics tendon by extrusion under physiological conditions. First, using alginate solutions as a model system for their similar rheological properties, we performed an extensive study of the helical extrusion instability which hinders the formation of regular threads. Based on this work, we then produced micrometric threads of dense collagen or mixtures of collagen and alginate which exhibit structures aligned along the thread axis. The physico-chemical conditions are chosen in order to obtain homogeneous threads with optimized mechanical properties. Finally, mesenchymal stem cells are seeded in vitro on collagen based threads. They colonize our matrices and express characteristic genes which suggests that they differentiate into tendon-like cells
13
von, Flotow Friedrich. "Characterization of an emerging tendon progenitor cell network during early embryonic tendon development". Thesis, Tufts University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1601708.
Testo completoAbstract (sommario):
Tendons are important tissues with unique mechanical properties necessary for their function. Tendon injuries require lengthy rehabilitation, with adult healing resulting in mechanically inferior scar tissue. A more complete understanding of the development of embryonic tendon may lead to advances in the field of tendon tissue engineering and regeneration. Mechanical properties of embryonic tendon are not dependent on the same factors as mature tendon, and during early development, embryonic tendon cells are maintained at a high density. They also contain actin filaments that increase in organization and span cells. These results suggest the importance of a tendon progenitor cell (TPC) network to emerging tendon functional properties. We examine the proliferation and apoptosis activities of resident TPCs as contributors to cell density maintenance. We characterize the TPC network by visualizing points of cell-cell contact via cell membrane staining as well as staining for the actin cytoskeleton. Finally, we characterize various cell-cell proteins as crosslinks in the TPC network and compare their expression and distribution. These data provide a deeper understanding of embryonic tendon development and the role of cellular contributions to the emerging functional characteristics of tendon.
14
Rajpar, Ibtesam Mohamed Husein. "Tendon Regeneration: Roles of Growth Factors and Phenotypic Diversity in Tendon Stem Cells". Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/88070.
Testo completoAbstract (sommario):
Tendon injuries significantly impact quality of life and are often career ending. Mesenchymal stem cell (MSC) therapy is known to augment intrinsic tendon healing, however, little is known of the stem cells endogenous to tendon, the microenvironmental cues that induce tendon differentiation, and whether individual cells in an inflammatory milieu respond differently to these cues. To address these questions, a three-dimensional tenogenesis assay was developed as an efficient and reproducible metric of cellular capacity to differentiate toward tendon. In contrast to more complex assays of tenogenesis, this design incorporates a simple apparatus using commercially available plasticware for the application of uniaxial static strain in in a type I collagen cell-seeded hydrogel construct. Tendon-related gene expression, glycosaminoglycan levels, elongated cell morphologies and parallel cell alignments are enhanced with BMP-12 induction over ten days of culture. This dissertation provides novel insight to the roles of growth factors in MSC tenogenesis.
Tendon healing in vivo is dependent on endogenous tendon stem cells (TSC) that mediate the inflammatory response to injury and promote synthesis of collagen and matrix remodeling, among other extracellular processes. Recent evidence suggests that these cells exist on a spectrum of differentiation potencies, and may be differently committed to the tendon fate. Individual stem cells were isolated from the tendon, and their capacities for proliferation, tri-lineage differentiation and tenogenesis were evaluated. Three distinct TSC phenotypes were revealed, and significant, positive correlations were found in quadra-differentiation potency (toward four lineages) and the expression of a strong, composite tendon phenotype.
These studies have important implications in the current standard-of-care in regenerative therapies for tendon. Our benchtop tenogenesis assay can be used to determine the therapeutic potential of allogeneic MSC lines and MSCs from novel sources for 'off-the-shelf' treatments. Our study of TSCs lends valuable insight to the diversity of cell phenotypes found in tendon, and the potential contributions of each phenotype to tendon healing and homeostasis. These results further strengthen the status of tendon as a superior source of stem cells for tendon repair.Ph. D.
Tendons are fibrous, elastic bands of collagen that connect muscles to bones and are essential to movement and proper functioning of the skeletal system. Weight-bearing tendons like the Achilles in humans and superficial digital flexor tendons in horses are particularly prone to damage and degeneration with overuse and/or aging. Bone marrow-derived stem cell treatments have shown promise in the reduction of pain and inflammation, and restoration of native tendon structure and function in cases of severe tendon injuries. However, the roles of stem cells in tendon healing, particularly their ability to transition to cell types native to tendon and integrate with an environment distinct from their own is unknown. Culturing of stem cells in three dimensional (3D) environments has enabled us to identify and understand the biochemical and mechanical signals that trigger stem cell transitions to tendon cells in tendons, but currently available 3D culture systems are complex and inefficient. In this dissertation we have developed a cost-effective and high throughput 3D culture system to assay the potential of stem cells to form tendon cells and composite tendon-like tissues. Toward this, we have also optimized the effects of known tendon proteins on the tendon fate in 3D culture of stem cells. Like most adult tissues, the tendon encompasses an in-house repository of stem cells. Tendon stem cells (TSCs) are primarily responsible for the inflammatory and reparative responses to tendon injury. Recent evidence suggests that TSCs are diverse in character, and differ from each other in their ability to form cells and tissues of fat, bone and cartilage. In this work, we provide evidence that TSCs are also differently committed to forming tendon tissue, and moreover that significant inter-relationships among gene expression patterns in these cells directly contribute to cultural diversity. In sum, our results provide novel insight to the roles of stem cells in tendon healing, particularly their response to subtle changes in their biochemical environment, and the contributions of individual cells in a milieu to a holistic reparative response.
15
Chia, Felix (Chek Nam). "Histology and gene expression of extensor tendons and pathobiology of extensor tendon tendinopathy using an ovine model". Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/17998.
Testo completoAbstract (sommario):
Tendons function to transmit the forces generated by muscle to bone, resulting in movement of a joint. However some tendons have more specialized functions. Functionally distinct tendons have differences in tissue composition that relate to differences in function. However, it is unclear whether functionally distinct tendons also behave differently following injury. This study aims to investigate the normal characteristics of ovine forelimb extensor tendons and the changes that occur following injury using a combination of histological and gene expression analysis. The lateral digital extensor tendon (LDET) and two branches of the common digital extensor tendons (CDET) in the forelimb of 6 sheep were collected to study normal extensor tendon characteristics. In another 6 sheep, the LDET and two branches of the CDET were transected and harvested 8 weeks later to evaluate the characteristics of injured extensor tendons. In the third group of 6 sheep, the LDET and two branches of the CDET were harvested 8 weeks after partial transection of the superficial digital flexor tendon (SDFT) in the same limb to evaluate the effects of tendinopathy of the SDFT on the normal extensor tendon characteristics. Samples were assessed using histology and gene expression. The results demonstrate that there are gene expression differences between the extensor tendons in the ovine forelimb and the changes in the ovine extensor tendons following surgery are similar to that of other tendons studied including the “energy storing” tendons. Partial transection of the SDFT had no effect on the extensor tendons.
16
JUNCOSA, LAURA NATALIA. "DESIGN PARAMETERS FOR TISSUE ENGINEERED IMPLANTS FOR RABBIT PATELLAR TENDON AND ACHILLES TENDON REPAIRS". University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1022080022.
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17
Hajipour, Ladan. "Gliding properties of the flexor tendon in zone 2 : tendon repair and pulley resection". Thesis, University of Leicester, 2016. http://hdl.handle.net/2381/37468.
Testo completoAbstract (sommario):
Flexor tendon injuries can lead to significant morbidity and the repair of such injuries in zone 2 is technically demanding. Technical skills from bench models transfer very well to practical use, and many mechanical simulators have been developed for investigating optimal flexor tendon repairs. Embalmed cadavers are markedly different from fresh human tissue, and the latter is becoming increasingly difficult to obtain due to public concern over the handling of tissue removed from cadavers and the risk of transmissible diseases. Pig and chicken tendons have previously been used due to their similar anatomy to human tendons, to allow basic repair and mechanical testing of suture techniques. Turkey tendons are larger than chicken tendons, allowing for better handling but have not been studied or used routinely for flexor tendon studies. The outcome of flexor tendon repairs relies heavily on post-operative rehabilitation and a strong, trigger free tendon repair that can withstand active movements. The surface changes of a repaired tendon can lead to increased friction and therefore an increased risk of rupture. There are currently no studies in the literature that have looked at: 1) the anatomy of turkey feet and their relevance in tendon repair research; 2) surface changes to the flexor tendon following tendon repair; and 3) the effect of pulley resection following tendon repair in paired specimens from the same animal. There are no strong studies in the literature that show whether paired tendons from the same animal exhibit the same gliding properties under experimental settings. This research aims to answer these questions.
18
Murrell, George Anthony Calvert St George Clinical School UNSW. "Nitric oxide and tendon healing". Awarded by:University of New South Wales. St George Clinical School, 2006. http://handle.unsw.edu.au/1959.4/31887.
Testo completoAbstract (sommario):
Nitric oxide is a small free radical generated by family of enzymes, the nitric oxide synthases. In a series of experiments performed over the last 15 years we showed that nitric oxide is induced by all three isoforms of nitric oxide synthase during tendon healing and that it plays a crucial beneficial role in restoring tendon function. In normal tendon we found very little nitric oxide synthase activity while in injured rat and human tendons nitric oxide synthase activity was expressed in healing fibroblasts in a temporal fashion. In healing rat Achilles tendon fibroblasts the first isoform to be expressed was endothelial nitric oxide synthase (eNOS), followed by inducible nitric oxide synthase (iNOS), and then brain or neuronal nitric oxide synthase (bNOS). Systemic inhibition of nitric oxide synthase activity decreased the cross sectional area and mechanical properties of the healing rodent Achilles tendons. Addition of nitric oxide via NO-flurbiprofen or NO-paracetamol enhanced rat Achilles tendon healing. Addition of nitric oxide to cultured human tendon cells via chemical means and via adenoviral transfection enhanced collagen synthesis, suggesting that one mechanism for the beneficial of nitric oxide on tendon healing might be via matrix synthesis. The final part of the work involved three randomized, double-blind clinical trials which evaluated the efficacy of nitric oxide donation via a patch in the management of the tendinopathy. In all three clinical trials there was a significant positive beneficial effect of nitric oxide donation to the clinical symptoms and function of patients with Achilles tendinopathy, tennis elbow and Achilles tendonitis.
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Molloy, Timothy John St George Clinical School UNSW. "Gene expression in healing tendon". Awarded by:University of New South Wales. St George Clinical School, 2006. http://handle.unsw.edu.au/1959.4/23939.
Testo completoAbstract (sommario):
Tendon injury is painful and often debilitating, and is a one of the most prevalent soft tissue injuries encountered in the clinic. While common, the underlying molecular and genetic processes of tendon damage and repair remain poorly understood. The work described herein used genome-wide expression analyses to investigate tendon injury and healing from three perspectives. The first identified novel gene expression in tendon fibroblasts following their stimulation with nitric oxide (NO). Of particular relevance to tendon healing was the observation that stimulated fibroblasts express a number of extracellular matrix (ECM) genes in response to NO in a dose-dependent manner, and that NO significantly affects cellular adhesion, a critical process during tendon repair. These findings will be of use when optimising dosages of NO delivery in future work investigating NO as potential treatment for tendon injuries. The second study examined gene expression in an acute tendon injury model in the rat at 1, 7, and 21 days post injury, roughly representing the inflammation, proliferation, and remodelling phase of wound repair. Several novel genes and pathways were found to be differentially expressed at each stage of healing. Of particular interest were the presence of a significant number of genes related to glutamate signaling, a method of cellular communication that has not previously been shown to exist in tendon. Also upregulated were a number of genes which have previously only been associated with embryonic development. Finally, gene expression in a supraspinatus tendinopathy model in the rat was investigated. Several genetic pathways were identified in tendinopathic tendons which have not previously been associated with the disease, and, analogous to the acute injury model study, glutamate signaling gene overexpression was also prevalent. Further in vitro studies showed that the expression of these genes in tendon fibroblasts were stimulated by glutamate treatment, which in turn upregulated pro-apoptotic pathways causing cell death. This may prove to be an important causative factor in the tendon degeneration seen in tendinopathy, in which apoptosis has been identified as playing a significant role. The results of these studies contribute to a better understanding of the aetiology of several extremely common pathologies of this soft tissue, and may help to develop more targeted therapies for increasing the efficacy of tendon healing in future.
20
Sundar, Siva. "Tendon attachment to the skeleton". Thesis, University College London (University of London), 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.497801.
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Oryan, Ahmad. "Experimental tendon injury and repair". Thesis, University of Bristol, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260544.
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Qiu, Yiwei. "In vitro tendon tissue engineering". Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:10d2b8fe-c485-44e4-ba03-abdad0da48f7.
Testo completoAbstract (sommario):
Tendon, ligament, and joint capsular injuries represent 45% of the 32 million musculoskeletal injuries each year in the United States. Tendon injuries are especially common, requiring surgical repair for the shoulder’s rotator cuff tendons (51,000 per year), the Achilles tendon (44,000 per year), and the patellar tendon (42,000 per year). Tissue engineering provides an alternative in the treatment of tendon lesions through replacement of an injured tendon segment. The purpose of this study was to develop a tendon construct in vitro for clinical reconstructive surgery. Human tenocytes were isolated from hamstring tendons of patients who had undergone anterior cruciate ligament (ACL) surgeries. These tenocytes were cultured with culture media (α-MEM) supplemented with various concentrations of foetal bovine serum (FBS) (0%, 1%, 5% and 10%) and in the presence of different growth factors such as PDGFBB (0, 5, 10 and 50ng/ml), basic FGF (0, 5, 10 and 50ng/ml), IGF-1 (0, 10 and 50ng/ml) and TGFβ-3 (0, 1 and 10ng/ml). Fractional factorial design was utilized to select the combinations of growth factors that supported the following criteria: (1) the maximal cell proliferation with a minimum differentiation of the tenocytes in the presence of the least concentration of FBS possible and (2) maintaining cell survival and promoting tenocyte differentiation in FBS free culture media. The results have shown that: (i) The tenocyte cell number when cultured for 14 days in media supplemented with 1% FBS, 50ng/ml PDGFBB and 50ng/ml bFGF matched that of the positive control (10% FBS-treated cells). Not only was the collagen synthesis significantly reduced in these growth factor-treated cultures compared to positive control tenocytes, but also a significant inhibition of the mRNA expression of various tenocyte differentiation markers (Scleraxis, Tenomodulin, Collagen type I and Decorin) was evident. IGF-1 did not promote significant cell proliferation under low serum conditions but did induce tenocyte differentiation in vitro. Examination of the cell morphology confirmed that tenocytes were capable of less differentiation when cultured with 1% FBS, 50ng/ml PDGFBB and 50ng/ml bFGF, this culture condition was termed “the expansion phase”; (ii) The cell survival was maintained for up to 14 days in serum free culture media supplemented with 50ng/ml IGF-1 and 10ng/ml TGFβ-3 whilst cell differentiation was enhanced and evident by the increase in collagen synthesis and cell morphology. Furthermore, mRNA expression of the aforementioned cell differentiation markers were also significantly increased, this culture condition was termed “the differentiation phase”; (iii) By combining the culture condition optimized for the expansion and differentiation phase sequentially, it was possible to maintain a long term 2-D tenocyte culture in vitro for up to 28 days. In these cultures, the presence of dense collagen formation was clearly evident whereas in positive control group (10% FBS group) such observation was not noted even after prolonged culturing period of up to 45 days. These results suggested that the sequential treatment of tenocytes with growth factors identified for the expansion and differentiation phases was significantly more superior than the standard 10% FBS treatment; (iv) By combining the expansion and differentiation phases optimized for the 2-D cultures, it was possible to maintain human tenocytes in a 3-D scaffold (Bombix silk) for up to 28 days. The tendon like constructs that were formed, macroscopically and microscopically resembled the human hamstring tendon. This observation was confirmed by using H&E staining, scanning electron microscopy and by detecting collagen type I immunohistochemically; (v) It was possible to further validate these findings using in vivo animal models. This was undertaken by implanting the tenocytes cultured sequentially in the defined culture media described above, into the quadriceps of Balb/c nude male mice for up to 30 days. The nature and specificity of the tendon like structure that was formed after this implantation was investigated by H&E staining and immunohistochemistry. It was revealed that the culture conditions that were optimized during the expansion and differentiation phases were suitable for generating a human tendon reconstruct; a finding which is of significance due to its potential for tendon reconstructive surgery.
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Salisbury, S. T. Samuel. "The mechanical properties of tendon". Thesis, University of Oxford, 2008. http://ora.ox.ac.uk/objects/uuid:97b73cf6-53bc-4606-b974-a1cdc662e9e8.
Testo completoAbstract (sommario):
Although the tensile mechanical properties of tendon have been well characterised, the viscoelastic and anisotropic properties remain uncertain. This thesis addresses the anisotropic and viscoelastic material properties of tendon. A method to characterise the three-dimensional shape of tendon is reported and experiments to characterise the fibre-aligned and fibre-transverse viscoelastic properties of tendon are presented. The cross-sectional profiles of bovine digital extensor tendons were determined by a laser-slice method. Linear dimensions were measured within 0.15 mm and cross-sectional areas within 1.7 mm². Tendons were compressed between two glass plates in creep loading at multiple loads. Compression was then modelled in a finite element environment. Tendon was found to be nearly incompressible and reproduction of its isochronal load-displacement curve was achieved with a neo-Hookean material model (E ≃ 0.3 MPa). The fibre-aligned tensile mechanical properties were described using a Quasi-Linear Viscoelastic model. The model was effective at reproducing cyclic loading; however, it was ineffective at predicting stress relaxation outside the scope of data used to fit the model. When all experimental results are considered together, two significant conclusions are made: (1) tendon is much stiffer in fibre-aligned tension than in fibre-transverse compression and (2) the fibre-aligned tensile response is strain dependant, while the transverse response is not.
24
Sawadkar, Prasad. "Engineering of a functional tendon". Thesis, University College London (University of London), 2015. http://discovery.ucl.ac.uk/1470606/.
Testo completoAbstract (sommario):
Reconstruction of a tendon following rupture is surgically challenging as each end of the tendon retracts leaving a substantial gap so that direct repair is often not feasible. To restore function, a tendon graft is required to bridge this defect and presently these gaps are filled with auto-, allo- or, synthetic grafts but they all have clinical limitations. To overcome this problem, tissue engineered collagen grafts were developed by a rapid process using compressed cell seeded type I collagen. Previously these constructs were tested in vivo in intercostal spaces of a lapine model to test immunocompatibility but material properties of the tissue engineered collagen grafts are currently unsuitable to withstand complete load bearing in vivo. A modified suture technique was developed to physiologically withstand and off load the tissue engineered collagen graft to aid integration in vivo. This modified suture method allowed only partial load to be transferred onto the tissue engineered collagen graft. Lapine tendons were used to test mechanical strength of repairs and a stress model was built. The break point for modified suture technique with tissue engineered collagen graft in situ was significantly higher compared to standard modified Kessler suture technique. To test the effect of the partial load on tenocytes, mechanobiology was studied under static and 10% cyclic loads using custom designed tensioning culture force monitors with immunohistology and matrix remodelling gene expression as quantifiable outcomes. Tendon fibroblast seeded tissue engineered collagen grafts were tested in vivo in a lapine model up to 12 weeks without immobilization. The gross observation at 3 and 12 weeks showed bridged integration of the graft without any adhesion with significant increase in the mechanical properties for 3 and 12 weeks as compared to 1 week. Histological analysis showed that tendon fibroblasts from the native tendon were able to migrate into the graft with higher collagen remodelling and graft maturation at 12 weeks as compared to 3 and 1 week. Insertion of tissue engineered collagen graft using a novel load bearing suture technique which partially loads in vivo showed integration, greater mechanical strength and no adhesion formation in the time period tested and it has inherent advantages as compared to the present day tendon grafts.
25
Kuchar, Olga Anna. "Development of animated finger movements via a neural network for tendon tension control". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq39322.pdf.
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Åström, Mats. "On the nature and etiology of chronic achilles tendinopathy". Lund : Dept. of Orthopaedics, Malmö University Hospital, Lund University, 1997. http://catalog.hathitrust.org/api/volumes/oclc/39705581.html.
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27
Gaut, Ludovic. "Mechanical and molecular signals underlying tendon cell differentiation". Electronic Thesis or Diss., Sorbonne université, 2018. http://www.theses.fr/2018SORUS301.
Testo completoAbstract (sommario):
Les tendons sont une forme unique de tissu conjonctif au sein du système musculosquelettique. Le développement, l’homéostasie et la réparation du tendon reposent sur des combinaisons de paramètres moléculaires et aussi mécaniques, régulant la production et l’assemblage des fibres de collagène. Notre objectif est de comprendre quelles sont les voies de mécanotransduction impliquées dans la différentiation tendineuse, via deux (co-)facteurs de transcription : EGR1 et YAP. Nous avons montré que l’expression du gène de tendon SCX, de EGR1 et l'activité de YAP sont réduites dans les tendons de membres de fœtus de poulet immobilisés. De plus, la reprise des contractions musculaires entraîne une reprise de l’expression des gènes de tendon comparable à celle des fœtus jamais immobilisés. La mécanobiologie du tendon a été étudiée avec des constructions cellulaires en 3-dimensions (3D) en gel de fibrine ou de collagène, faits de cellules souches mésenchymateuses. La perte de tension de ces constructions a induit une chute de l’expression de Egr1, des gènes de tendon et de l’activité de YAP. Une surexpression de Egr1 dans les constructions 3D en gel de fibrine sans tension a empêché la chute d’expression des gènes de tendon. L’activité de YAP et l’expression de Scx ont augmenté en étirant les constructions en gel de collagène. L’inactivation de l’activité de YAP par traitement à la verteporfin (VTPF) a induit une diminution de l’expression des gènes de tendon, qui n’a pas été restaurée lorsque ces constructions traitées ont été étirées. Ensemble, ces résultats montrent l’importance de YAP et EGR1 en aval des signaux mécaniques pour réguler la différentiation des cellules du tendonTendons are unique forms of connective tissue of the musculoskeletal system. Tendon development, homeostasis and repair rely on specific combinations of mechanical and molecular factors regulating the production and assembly of collagen fibers. Our objective is to decipher the mechanotransduction pathways underlying tendon cell differentiation, through the activity of two transcription (co-)factors, EGR1 and YAP. We showed that the expression of the tendon gene SCX, the mechanosensitive gene EGR1 and YAP activity were downregulated in limb tendons of immobilized chicken fetuses. Restored muscle contraction after immobilization led to a recovery of tendon gene expression. Tendon mechanobiology was studied in vitro in fibrin- or collagen-based 3-dimensional (3D) constructs made of mesenchymal stem cells and mimicking tendon formation. Tension release in fibrin and collagen 3D-constructs induced a drop of the expression of Egr1, tendon genes and YAP activity. Overexpression of Egr1 was able to prevent the downregulation of tendon gene expression in de-tensioned fibrin 3D-constructs. YAP activity was upregulated in dynamically stretched collagen 3D-constructs and was paired with the expression of the tendon gene Scx. Chemical knock-down of YAP activity with Verteporfin (VTPF) treatment showed a decrease in the expression of YAP target genes and the tendon genes. Besides, dynamic stretch applied on VTPF-treated constructs did not restore tendon gene expression, conforting the role of YAP as an intracellular relay of mechanical cues in tendon cells. Altogether, these results highlight the importance of EGR1 and YAP downstream of mechanical forces during tendon cell differentiation
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Gerber, Popp Ariane. "Management of irreparable subscapularis tendon tears". [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=973507578.
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Berglund, Maria. "Biomolecular Aspects of Flexor Tendon Healing". Doctoral thesis, Uppsala universitet, Handkirurgi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-120304.
Testo completoAbstract (sommario):
Flexor tendon injuries in zone II of the hand (i.e. between the distal volar crease and the distal interphalangeal joint) can be costly for both the afflicted individual and society because of the high cost of a long rehabilitation period, complicated by tendon ruptures or scarring with adhesion formation, causing impaired range of motion. The aim of the present thesis was to characterize more fully the deep flexor tendon, the tendon sheath and their response to injury in a rabbit model in order to find potential targets to improve the outcome of repair. The intrasynovial rabbit deep flexor tendon differed from the extrasynovial peroneus tendon in the expression of collagens and transforming growth factor-β1 gene expression. Differences were also found in collagen III and proteoglycans between regions of the flexor tendon subjected to either compressive or tensile load. After laceration and subsequent repair of the flexor tendon, a shift in collagen gene expression from type I to type III occurred. Proteoglycans were generally increased with the notable exception of decorin, a potential inhibitor of the profibrotic transforming growth factor-β1 which was markedly increased during the first two weeks after repair in tendon tissue but remained unaltered in the sheaths. Both vascular endothelial growth factor and basic fibroblast growth factor mRNA levels remained essentially unaltered, whereas insulin-like growth factor-1 increased later in the healing process, suggesting potential beneficial effects of exogenous addition, increasing tendon strength through stimulating tenocyte proliferation and collagen synthesis. Matrix metalloproteinase-13 mRNA levels increased and remained high in both tendon and sheath, whereas there was only a transient increase of matrix metalloproteinase-3 mRNA in tendon. We could also demonstrate a significant increase of the proportion of myofibroblasts, mast cells and neuropeptide containing nerve fibers in the healing tendon tissue, all components of the profibrotic myofibroblast-mast cell-neuropeptide pathway.Biomolecular aspects of flexor tendon healing
30
Lantto, I. (Iikka). "Acute Achilles tendon rupture:epidemiology and treatment". Doctoral thesis, Oulun yliopisto, 2016. http://urn.fi/urn:isbn:9789526211985.
Testo completoAbstract (sommario):
Abstract The Achilles tendon is the strongest and largest of human tendons, and its proper function is essential for normal gait. Most acute Achilles tendon injuries occur during sports, particularly in ball games. The purposes of this study were (1) to examine the incidence of total Achilles tendon rupture (ATR) over a 33-year period in the city of Oulu and to investigate its changes with respect to age, sex, and injury mechanism. (2) to compare ≥10-year outcomes of two postoperative regimens after ATR repair: early weightbearing with early mobilization versus early weightbearing with early immobilization in tension, (3) to compare clinical outcome and calf muscle strength recovery after conservative treatment or open surgical repair of acute ATR, followed by identical accelerated rehabilitation programs. The overall incidence per 100 000 person years increased from 2.1 in 1979 to 21.5 in 2011. The incidence increased in all age groups. The incidence of sports-related ruptures increased during the second 11-year period, whereas the incidence of non-sports-related ruptures increased steadily over the entire study period. Early mobilization and immobilization in tension after ATR repair resulted in similar clinical outcomes and isokinetic strengths. Regardless of patient satisfaction with the operative treatment, calf muscle strength did not recover normally, even at the 10-year follow-up. Surgery and conservative treatment of acute ATR resulted in similar Achilles tendon performance score after 18 months, but surgery restored calf muscle strength earlier. Surgery also resulted in better health-related quality of life in the domains of physical functioning and bodily pain. Conservative treatment with a functional protocol is recommended for a large majority of patients. However, patients with high physical expectations could still benefit from operative treatment. In conclusion, the incidence of ATR is rising, postoperative immobilization and early mobilization result in similar long-term results in terms of the Achilles tendon performance score and calf muscle function, and conservative treatment with a functional protocol is the preferred treatment for the majority of patientsTiivistelmä Akillesjänne on ihmisen suurin ja vahvin jänne ja sen kunnollinen toiminta on edellytys normaalille kävelylle. Suurin osa akillesjänteen repeämistä syntyy urheilussa, erityisesti pallopeleissä. Ensimmäisessä osatyössä oli tarkoitus selvittää täydellisten akillesjänteen repeämien esiintyvyys Oulussa 33 vuoden aikana ja selvittää potilaiden ikä ja sukupuoli sekä vammamekanismi. Toisessa osatyössä vertailtiin akillesjänteen repeämän hoitotuloksia 11 vuotta vamman jälkeen. Tässä tutkimuksessa verrattiin kahta erilaista leikkauksen jälkeistä hoitomenetelmää; toisessa sallittiin varhainen varaaminen ja nilkan liikuttelu kun taas toisessa sallittiin varhainen varaaminen, mutta nilkka kipsattiin ojennukseen. Kolmannessa osatyössä vertailtiin tuloksia leikattujen ja ilman leikkausta hoidettujen potilaiden välillä. Molemmat ryhmät hoidettiin samanlaisella irrotettavalla varaamisen sallivalla lastalla. Akillesjänteen repeämien esiintyvyys oli 2.1/100 000 vuonna 1979 ja nousi vuoteen 2011 mennessä 21.5/100 000:een ja nousua oli kaikissa ikäryhmissä. Urheiluun liittyvät repeämät lisääntyivät erityisesti jakson keskimmäisen 11-vuotis jakson aikana kun taas urheiluun liittymättömät repeämät lisääntyivät koko seurantajakson ajan. Vertailtaessa kahta erilaista leikkauksen jälkeistä hoitomenetelmää todettiin ettei potilaiden välillä ollut eroa kliinisissä mittareissa tai voimissa 11 vuotta vamman jälkeen. Vaikka potilastyytyväisyys oli hyvä ei pohkeen voima palautunut normaaliksi edes 11 vuotta vamman jälkeen. Vertailtaessa leikkauksella ja ilman leikkausta hoidettuja potilaita ei myöskään todettu eroja kliinisissä mittareissa, mutta kirurgisella hoidolla voima palautui hiukan nopeammin ja ero myös säilyi 18 kuukautta vammasta. Myös elämänlaatumittarilla mitattuna leikkauksella hoidetut olivat kivun ja fyysisen toiminnan osalta tyytyväisempiä. Suurimmalle osalle potilaista konservatiivinen hoito sopii erinomaisesti, mutta jotkut fyysisesti aktiiviset potilaat hyötynevät leikkaushoidosta
31
Sanders, David W. "Biomechanical analysis of flexor tendon repairs". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0021/MQ42197.pdf.
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32
Yang, Xin. "The quantification of Achilles tendon neovascularity". Thesis, Cardiff University, 2010. http://orca.cf.ac.uk/54198/.
Testo completoAbstract (sommario):
In the investigation of the correlation between VON and clinical severity, the mean VON was definitely greater than that in healthy Achilles tendon. Neovascularization was noted in 97.5% (n = 39) symptomatic Achilles tendons in 30 patients. The VAS showed a positive correlation with VON with a Spearman correlation coefficient of 0.326 (
33
Wang, Xiao Tong. "Creep and fatigue properties of tendon". Thesis, University of Leeds, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.444440.
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34
Liu, Renjie. "Advanced polymeric materials for tendon repair". Thesis, Queen Mary, University of London, 2018. http://qmro.qmul.ac.uk/xmlui/handle/123456789/54465.
Testo completoAbstract (sommario):
Tendons transfer forces from muscle to bone and allow the locomotion of the body. However, tendons, especially for tendons in the hand, get lacerated commonly in different injuries and the healing of tendon within the narrow channel in the hand will normally lead to tendon adhesion and sacrificed tendon mechanics. Researches have been focused on addressing tendon adhesion prevention but neglecting healed tendon mechanics. This thesis discusses the principles and challenges in the design of biomaterials regarding flexor tendon repair with advanced polymer chemistry and materials science. A rational platform, not only focusing on the prevention of tendon adhesion, but devoting more efforts on final healed properties of tendons via implementing glycopolymer-based materials to guide tendon cells attachment, was designed, fabricated and characterized. Controlled ring opening polymerizations and atom transfer radical polymerizations were combined for the synthesis of miktoarm well-defined block copolymers. Para-fluorine click reactions were then implemented to afford glycopolymers with glucose units. Obtained copolymers were transformed into 3D membranes constituting a porous fibrous structure utilizing electrospinning. The aligned structure was then fabricated to optimize the mechanics of these materials for practical application as well as reconstruct normal tendon physiological structure. Lastly, the toxicity, cell affinity and cell activity of obtained materials were evaluated in vitro employing tendon cells as a cell line to confirm the suitability of obtained platforms for flexor tendon repair.
35
Mombrun, Denis. "Les ruptures fraîches du tendon d'Achille". Caen, 1994. http://www.theses.fr/1994CAEN3047.
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36
Edsfeldt, Sara. "Intrasynovial flexor tendon injuries and repair". Doctoral thesis, Uppsala universitet, Handkirurgi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-316559.
Testo completoAbstract (sommario):
Complications after surgical repair of intrasynovial flexor tendon injuries in the hand occur despite advanced suture techniques and structured postoperative rehabilitation regimens. Early controlled tendon mobilization prevents adhesion formations and improves tendon healing as well as digit range of motion. To allow early postoperative rehabilitation, the strength of the repair must withstand forces created during the rehabilitation maneuvers. Improvements in suture biomechanics have increased repair strength, but up to 18 percent of repaired tendons still rupture. The overarching aim of this thesis was to investigate how to best treat intrasynovial flexor tendon injuries with limited risk of repair rupture, decreased adhesion formations, and to estimate the effect of individual patient and injury characteristics on functional outcome. In two observational studies, we identified risk factors for rupture of repaired intrasynovial flexor digitorum profundus (FDP) tendons, and studied effects of these risk factors on the long-term outcome. Age was associated with increased risk of repair rupture and impaired digital mobility the first year after surgical repair. Concomitant flexor digitorum superficialis (FDS) transection was associated with increased risk of repair rupture without affecting digital mobility. Concomitant nerve transection lowered the rupture risk without affecting digital mobility. To better understand forces generated in the flexor tendons during rehabilitation maneuvers, we measured in vivo forces in the index finger FDP and FDS tendons during rehabilitation exercises. Highest forces were measured during isolated FDP and FDS flexion for the FDP and FDS respectively. For the FDS tendon, higher forces were observed with the wrist at 30° flexion compared to neutral position, and for the FDP tendon, forces were higher during active finger flexion compared to place and hold. PXL01 is a lactoferrin peptide with anti-adhesive effects previously demonstrated in animal studies and a clinical trial to improve digital mobility when administrated around repaired tendons. We studied the mechanism of action of its corresponding rabbit peptide, rabPXL01 in sodium hyaluronate (HA) in a rabbit model of flexor tendon transection and repair and used RT-qPCR to assess mRNA levels for different genes. Increased levels of PRG4 (encoding lubricin) were observed in rabPXL01 in HA treated tendons. The expression of Interleukin 1β, 6, and 8 was repressed in tendon sheaths. RabPXL01 in HA might stimulate the release of lubricin and diminish inflammation, which correspondingly reduces tendon-gliding resistance and adhesion formations during postoperative rehabilitation exercises. The results of this thesis suggest individually adapted treatment plans, depending on repair strength, patient and injury characteristics, as a possible way to improve outcome after flexor tendon repair.
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Popp, Ariane Gerber. "Management of irreparable subscapularis tendon tears". Doctoral thesis, Humboldt-Universität zu Berlin, Medizinische Fakultät - Universitätsklinikum Charité, 2005. http://dx.doi.org/10.18452/13956.
Testo completoAbstract (sommario):
Zur Zeit gibt es keinen optimalen Sehnentransfer zur Behandlung von irreparablen Ruptur der Subscapularissehne. Obwohl der Pectoralis major Transfer als Therapie der Wahl gilt, bleibt der Kraftvektor der verlagerten Sehne-Muskeleinheit sehr unterschiedlich zum Kraftvektor des Subscapularismuskels. Das Ziel dieser Arbeit war, ein neues Konzept zur Behandlung von irreparablen Subscapularisrupturen zu definieren, bei dem die Subscapulariseinheit selektiv mittels Teres major(TM) und Pectoralis major (PM) wiederhergestellt wird. In den Kadaverstudien dieser Arbeit konnte gezeigt werden, dass sich der M. Teres major anatomisch-chirurgisch als Sehnentransfer zur Rekonstruktion der unteren Hälfte des M. Subscapularis eignet. Darüberhinaus wurde in einer dreidimensionalen Vektoranalyse gezeigt, dass der Kraftvektoren vom verlagerten Teres major sich nicht signifikant vom Kraftvektoir des unteren Anteils des Musculus subscapularis unterscheidet. Es wurde weiterhin gezeigt, dass Modifikationen des Pectoralis major transfer durch Reroutingmassnahmen zu einer deutlichen Verbesserung seines Kraftvektors im Vergleich zum oberen Amteil des Musculussubscapularis führt. Basierend auf den neuen anatomischen und biomechanischen Erkenntnissen wurde im letzten Teil dieser Schrift das neue Konzept klinisch angewandt. Dabei wurde bei 7 Patienten mit einer irreparablen Subscapularisruptur nach multiplen Voreingriffen eine selektive Rekonstruktion mittels kombinierten TM-PM Transfer durchgeführt. Es traten keine Komplikationen auf und alle Patienten hatten eine deutliche Linderung Ihrer Schmerzen und eine Verbesserung der Funktion. Somit erscheint diese neue Transferoperation eine sichere und effiziente Option zur Behandlung irreparabler Subscapularisrupturen darzustellen.Currently there is no optimal tendon transfer procedure for the management of irreparable subscapularis lesions. Although the pectoralis major transfer is considered as the gold standard in the treatment of irreparable subscapularis tears, the force vector orientation of this transfer may not be optimal in comparision to the situation at the subscapularis muscle. Objective of this monograph was to establish the anatomical and biomechanical basis for a new concept of selective subscapularis reconstruction combining a teres major transfer to the pectoralis major transfer. In the cadaveric part of this work, it could be demonstrated that the teres major is a safe and biomechanically logical transfer for reconstruction of the lower part of the subscapularis. The analysis was carried on to define the optimal transfer for reconstruction of the upper part of the subscapularis. It was possible to determine the biomechanical effect of rerouting procedures of the pectoralis major transfer. Passing the tendon underneath the conjoined tendon appeared to be the most effective way to improve the direction of the pectoralis major transfer for subscapularis reconstruction. However this technique is demanding when the plane underneath the conjoined tendon is scarred and the pectoralis major is bulky. In such cases there is a risk to injure the musculocutaneous nerve. Therefore, rerouting the sternal part of the pectoralis major underneath its clavicular part (sPM tansfer) may be a safer option. Finally, based on the acquired anatomical and biomechanical data, early clinical experience in a series of 7 patients was reported. Although the clinical series was small, the combined TM-sPM transfer appeared to be a valuable and a safe alternative to treat irreparable subscapularis tears. An interesting observation in this study was that the transfer was able to recenter the statically subluxed humeral head in two cases. This could be attributed to the dynamic hammock built by the transferred teres major. The early promising subjective and objective results presented here encourage for further investigation.
38
Lalley, Andrea L. "Identifying and Evaluating Novel Biological Targets to Improve Musculoskeletal Tissue Engineering Strategies". University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1416231302.
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Alam, Nawsheen. "The cellular biology of tendon grafting and graft integration". Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/the-cellular-biology-of-tendon-grafting-and-graft-integration(ae75cfd2-86f4-4d5d-9511-edca52d2a6f6).html.
Testo completoAbstract (sommario):
Background: Prolonged recovery after tendon injury has given rise to the need for innovative therapy including tendon engineering and cell based therapies. The role of cells in grafted or engineered tendon is poorly understood. Clarifying the persistence of grafted tissue is fundamentally important to ensure that tissue engineering strategies are fit for clinical application. We have devised a murine model for tendon grafting that allows for cell tracking and the assessment of tendon integration and engineered construct integration. Materials and methods: We studied the macroscopic and microscopic architecture of the mouse Achilles tendon to investigate its properties as a study model. Using microsurgical techniques, transgenic tendon grafting procedures were then carried out between C57B/L6 wild type and GFP (Green Fluorescent Protein) mice Achilles tendon. The temporal and spatial fate of the cells in the graft was assessed using quantitative serial histology and immunohistochemistry with Three Dimensional reconstruction. Markers for proliferation, collagen synthesis, cell death and inflammatory infiltrate were used. The Achilles tendon model was also applied to test its applicability to investigate tissue engineered tendon constructs developed in vitro. Results: GFP positive graft cells were seen at Day 3 and Day 21 but disappeared by Day 90. At Day 21both graft cells and the cells of the recipient tendon showed intense collagen synthetic activity. At the same time both graft and host tendon cells began to show signs of apoptosis which continued till Day 90. Subcutaneous tissue and paratenon maintained a much higher level of cellularity, cell proliferation, collagen synthesis and apoptosis at all time. The interplay between cell activity and cell death appear to play central role in the integration of the tendon graft. The persistence of tissue engineered tendon constructs was far less than syngenic or autografts. The Achilles tendon model proved to be a robust and economically viable model for testing of biomaterials particularly at the early stage of their development. Conclusion: The cells of tendon grafts persist only for a finite time before being repopulated by host cells. Tissue engineered cell-based constructs do not provide sufficient persistence to substitute in place of syngenic or autologous graft options. Future designs of engineered tendon should facilitate tendon integration and aim to persist for longer periods of time in order to participate in the healing process.
40
Özer, Özgür Baydar Metin Lütfi. "Ön çapraz bağ rekonstrüksiyonlarında anterior tibial tendon allogrefti ve dörtlü hamstring tendon otogrefti kullanılan olguların fonksiyonel karşılaştırılması /". Isparta : SDÜ Tıp Fakültesi, 2004. http://tez.sdu.edu.tr/Tezler/TT00171.pdf.
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Fidalgo, Sara Lourenço de Matos Sêrro. "Tenoscopic examination of the digital flexor tendon sheath a retrospective analysis of 86 horses (2016)". Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2017. http://hdl.handle.net/10400.5/13663.
Testo completoAbstract (sommario):
Dissertação de Mestrado Integrado em Medicina VeterináriaThe digital flexor tendon sheath (DFTS) enfolds the digital flexor tendons and their associated structures, protecting and facilitating its movements. Tenoscopic examination of the DFTS has become a routine procedure in equine surgical practice since it is a minimal invasive technique that allows the exploration of the sheath structures with direct observation of lesions and therefore, confirmation of a diagnosis and, in some cases, early treatment. In this work, medical records of horses that underwent tenoscopic examination of the DFTS in 2016 at four different equine hospitals in the United Kingdom had their medical records reviewed. Eighty-six cases (93 DFTSs) were included in this study. There were 31% Thoroughbreds, 28% Warmbloods, 20% Coldbloods, 12% Ponies and 9% unknown. Ninety-eight percent of horses were lame at the time of clinical examination, effusion was present in 94% of the DFTSs and the hindlimbs were more frequently intervened (61%). Palmar/plantar annular ligament (PAL) constriction (43%) was the most common pathology, followed by sheath penetration (27%), and tears of the flexor tendons (24%) and manica flexoria (MF) (19%). Other diagnosis included tendonitis, infectious tenosynovitis, fibrosis, diseases of sesamoidean ligaments and ganglion cysts. Results show that PAL constriction, flexor tendon and MF tears were diagnosed more frequently in the hindlimbs (72.5%, 64% and 90%, respectively), while traumatic injuries affected more forelimbs (60%). Coldbloods and Ponies were predisposed to MF tears and PAL constriction, Warmbloods to PAL constriction and flexor tendon tears, and Thoroughbreds to traumatic injuries. Young horses (<10 years) had a higher incidence of traumatic injuries, whereas older horses (>10 years) were commonly diagnosed with MF tears and PAL constriction. Tenoscopy was of extreme importance as a diagnostic method, considering that MF tears were only identified by other diagnostic methods in 61% of cases, flexor tendon tears in 67% and PAL constriction in 53%. In conclusion, tenoscopy was proven to be a simple and useful diagnose and treatment method of DFTS pathology, even though the long term follow-up of the analysed horses was not studied.
RESUMO - TENOSCOPIA DA BAÍNHA DIGITAL DOS TENDÕES: ANÁLISE RETROSPETIVA DE 86 CAVALOS (2016) - A bainha digital dos tendões (BDT) envolve os tendões flexores digitais e as estruturas associadas aos mesmos, protegendo-os e facilitando os seus movimentos. A examinação tenoscópica da BDT tornou-se um procedimento de rotina em cirurgia de equinos, visto ser uma técnica cirúrgica minimamente invasiva que permite a observação direta de lesões, confirmação de diagnósticos e, em alguns casos, tratamento precoce. Neste trabalho foram revistos os registos médicos dos cavalos que foram submetidos a tenoscopia da BDT em 2016 em quatro hospitais de equinos no Reino Unido. Oitenta e seis casos (93 BDTs) foram incluídos no presente estudo sendo que 31% eram de raça puro-sangue inglês, 28% de sangue quente, 20% de sangue frio, 12% póneis e 9% de raça desconhecida. Noventa e oito porcento dos cavalos exibiram claudicação e 94% dos membros tinham distensão da BDT. Os membros posteriores foram os mais intervencionados (61%). Constrição pelo ligamento anular palmar/plantar (LAP) (46%) foi a doença mais comum, seguida de lesão percutânea da bainha (27%), e lesões marginais dos tendões flexores (24%) e roturas da manica flexoria (MF) (19%). Outros diagnósticos incluíram tendinite, tenosinovite infeciosa, fibrose, doenças de ligamentos sesamoideus e quistos. Os resultados indicam que a constrição pelo LAP, lesões marginais dos tendões flexores e roturas da MF são mais frequentes nos membros posteriores (72.5%, 64% e 90%, respetivamente), enquanto lesões percutâneas afectam mais os membros anteriores (60%). Cavalos de sangue frio e póneis foram mais propensos a roturas da MF e constrição pelo LAP, cavalos de sangue quente a constrição pelo LAP e lesões marginais dos tendões flexores, e puro-sangue inglês a lesões traumáticas da BDT. Cavalos jovens (<10 anos) tiveram maior incidência de lesões traumáticas mas cavalos mais velhos (>10 anos) foram mais afetados por roturas da MF e constrição pelo LAP. A tenoscopia é de extrema importância como método de diagnóstico, considerando que roturas da MF apenas foram identificadas por outros métodos em 61% dos casos, lesões marginais dos tendões flexores em 67% e constrição pelo PAL em 53%. Em conclusão, foi provado que a tenoscopia é uma técnica simples e útil de diagnóstico e tratamento de doenças da BDT, embora o acompanhamento da recuperação do cavalo a longo prazo não tenha sido estudado.
N/A
42
Cowder, Justin Dennis. "Testing and application of a novel hybrid combination of ultrasound and motion analysis for estimation of Achilles tendon moment arms in vivo". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 97 p, 2008. http://proquest.umi.com/pqdweb?did=1597632581&sid=4&Fmt=2&clientId=8331&RQT=309&VName=PQD.
Testo completo
43
Achkire, Younes. "Active tendon control of cable-stayed bridges". Doctoral thesis, Universite Libre de Bruxelles, 1997. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/212180.
Testo completo
44
Williams, Lakiesha Nicole. "MULTISCALE STRUCTURE-FUNCTION RELATIONS OF A TENDON". MSSTATE, 2006. http://sun.library.msstate.edu/ETD-db/theses/available/etd-07062006-214357/.
Testo completoAbstract (sommario):
In 1998, the United States National Committee on Biomechanics (USNCB) established an evolving discipline called Functional Tissue Engineering (FTE). In establishing this discipline, the goals of the USNCB were to advance FTE by increasing awareness among tissue engineers about the importance of restoring function when engineering tissue constructs. Another goal was to encourage tissue engineers to incorporate these functional criteria in the design, manufacturing and optimization of tissue engineered constructs. Based on this motivation, an investigation of the structure and mechanical properties of the rabbit patellar tendon will be executed, with the ultimate goal of creating a multiscale soft tissue model based on internal state variable (ISV) theory. Many continuum scale models, mostly phenomenological and microstrucutral, have been created to contribute to the understanding of the complex functional properties of the tendon, such as its anisotropy, inhomogeneity, nonlinearity, and viscoelasticity. However, none of these models have represented the mechanical behavior of the tendon in the presence of internal structural change on a multiscale level. The development of a multiscale ISV model will allow the capture of the irreversible, path history dependent aspects of the material behavior. The objective of this study is to contribute to the multiscale ISV model development by quantifying the structure- property relations. In particular, the fibril distribution at the microstructural level and the resultant multiaxial stress states (longitudinal and transverse compression and longitudinal tension) will be examined).
45
Tillander, Bo. "The Supraspinatus Tendon : Clinical and histopathological aspects". Doctoral thesis, Linköping : Univ, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-5224.
Testo completo
46
Zhao, Jing. "Tendon and ligament repair regeneration and maturation /". Connect to this title online, 2008. http://etd.lib.clemson.edu/documents/1211389215/.
Testo completo
47
Schepull, Thorsten. "Stiffness of the healing human Achilles tendon". Doctoral thesis, Linköpings universitet, Institutionen för klinisk och experimentell medicin, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-91727.
Testo completoAbstract (sommario):
Achilles tendon ruptures in humans are followed by a long period of immobilisation, rehabilitation and limitations of physical activity and sometimes work also. This prolonged period probably leaves a marginal for improvement in the management of this injury. Animal studies have shown that there are several possibilities to influence and improve tendon healing. The aim of this thesis was to find a way to examine the mechanical properties of the healing human Achilles tendon and, by using that method, to gain a better understanding of the tissue properties and healing process in these tendons. It was also our aim to use our knowledge from animal studies in an attempt to improve tendon healing in humans. We developed a radiological method using radiostereophotogrammetric analysis (RSA) and computed tomography (CT), which enabled us to measure the stiffness of the healing Achilles tendon. The results of these measurements, as early as 7 weeks after injury correlated with the late clinical results in all studies. Clinical results were measured using a heel-raise test comparing the injured with the non-injured tendon. We could not find a significant difference in stiffness between patients treated surgically or non-surgically. Neither could we demonstrate that platelet-rich plasma improved the mechanical properties of the healing tendon or the clinical outcome, within the limits of the statistical power. In contrast, patients following a specific training programme with early tension loading of the tendon twice a day developed stiffer tendon tissue later in the healing process. Since RSA is unsuitable for routine clinical use, we evaluated the possibility to use radiodensity findings from CT as a proxy for healing and its correlation to mechanical and clinical results. Density and mechanical properties correlated strongly when analysing all time points together, but only weakly at each particular point in time. Density may still be useful in describing mechanical properties at a later stage of repair, but this remains to be seen. In conclusion, these studies show that early mechanical properties correlate to late clinical outcome and that the early use of daily tension loading sessions leads to an improvement in the mechanical properties of the tendon tissue.
48
Scott, Alexander. "Tendon overuse pathology : clinical and laboratory studies". Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/5621.
Testo completoAbstract (sommario):
Background: Painful tendon overuse pathology (tendinosis) is poorly understood. The
objectives were to identify major cell populations within clinical tendinosis lesions, and
to examine factors involved in the regulation of tendon cell death, survival, or
proliferation. The overarching hypothesis was that both cell death and cell proliferation
play roles in the development of tendinosis.
Methods:
1: Chronic patellar tendinosis tissue was compared with normal, pain-free patellar tendon
using Western blot, immunohistochemistry and in situ hybridization. A variety of cell
types were examined in relation to relevant features of soft tissue injury and repair
including cellular proliferation and versican expression.
2: In adult male rats, early tendinosis was induced in the supraspinatus tendon by 4-16
weeks of mechanical loading (eccentric exercise). Tendons were analyzed
morphologically using polarized light and transmission electron microscopy, and by
immunolabeling for molecular markers of proliferation and survival.
3: The influence of IGF-I on tenocyte survival was tested in response to chronic hypoxia
in a cell-culture setting.
Results
1: Tendinosis was characterized by proliferation of tenocytes, endothelial cells, and
smooth muscle cells within a versican-enriched extracellular matrix. Mast cells were also
more numerous in patient biopsies, whereas macrophages and lymphocytes were virtually
absent. VEGF expression was increased in endothelial cells from tendinosis tendons and
was more marked in patients with shorter symptom duration.
2: Mechanical loading of the rat supraspinatus tendon by downhill running caused focal
tendon lesions characterized by tenocyte proliferation, collagen disarray and
glycosaminoglycan accumulation. Tenocytes in these areas of injury demonstrated a
proliferative response which correlated with IGF-I expression and phosphorylation of
ERK-l/2and IRS-1.
3: Prolonged hypoxia of primary tenocyte cell cultures resulted in tenocyte apoptosis and
caspase activation. Apoptosis could be prevented dose-dependently by IGF-I, which
activated the PKB survival pathway
Conclusions
The current studies outlined predominant cell populations present in tendinosis lesions
and identified factors which may be involved in regulating their death, survival and
activity. These experiments have opened up new avenues of research into the
pathophysiology of tendinosis.
49
Grewal, Navdeep. "The link between hypercholesterolemia and tendon pathology". Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44472.
Testo completoAbstract (sommario):
Tendinopathy is a major cause of morbidity in athletic populations and in the work force, traditionally thought to occur as a consequence of an imbalance between damage (resulting from mechanical loading) and repair. However, one third of the cases for midportion Achilles tendinopathy occur in sedentary individuals, and recent data suggests an association between hypercholesterolemia and the occurrence of tendon rupture or tendinopathy. The aim of this study was to examine the link between elevated lipids and tendon pathology. We used an apolipoprotein E-knockout model (ApoE-KO), in which apolipoprotein E deficiency leads to development of atherosclerosis. We hypothesized that tendons from ApoE-KO mice fed a high fat diet, in comparison to those fed a regular chow diet and the wild type (non-atherosclerotic mice), will demonstrate increased lipid deposition, increased cross-sectional area, and increased expression levels of collagen genes (Col1a1 and Col3a1), a growth factor gene (TGF-β), and an indicator of mast cell presence (Cpa3).
To test these hypotheses, ApoE-KO and control mice were fed a regular or high fat diet and sacrificed at different time points: 0, 15, and 30 weeks. The morphological properties were examined on H&E stained Achilles tendon sections while the lipid content was analyzed with Oil Red O staining. Tendon thickening was measured by ultrasonography of patellar tendon cross-sectional area. qPCR analysis was carried out on tail tendons at 30 week time point to analyze gene expression of Cpa3, TGF-β, Col1a1, and Col3a1.
ApoE-KO mice developed xanthomatous lesions, and showed less weight gain than control mice. ApoE-KO mice showed no appreciable changes in tendon histomorphology. Compared to control mice, ApoE-KO mice had lower tendon lipid content but demonstrated an increase in tendon cross-sectional area. Col1a1 gene expression levels were decreased in ApoE-KO mice. Cpa3, TGF-β, and Col3a1 showed no differences between strains; however, Cpa3 expression was decreased in mice that were fed the high fat diet. ApoE-KO mice demonstrated significant tendon alterations, demonstrating thicker tendons with decreased collagen expression. Future work is required to determine the mechanism involved and the potential impact on tendon function.
50
Meghoufel, Ali. "Analyse des images échographiques du tendon équin". Mémoire, École de technologie supérieure, 2011. http://espace.etsmtl.ca/889/1/MEGHOUFEL_Ali.pdf.
Testo completoAbstract (sommario):
Les articulations du cheval de sport de haut niveau sont très sollicitées, ce qui peut entraîner
de multiples tendinopathies telles que la déchirure ou la rupture du Tendon Fléchisseur
Superficiel du Doigt (SDFT). L’imagerie par échographie, peu coûteuse, non invasive et
propice à l’exploration de la structure interne du SDFT est régulièrement utilisée pour
évaluer l’intégrité du tendon. Cependant, le pronostic fonctionnel sur l’état des tendons à
partir des examens cliniques est souvent difficile à poser. Cette difficulté résulte du manque
d’information a priori des structures visibles sur les images échographiques cliniques qui
peut entraîner une interprétation subjective ou erronée sur l’état du tendon. Une autre
difficulté est le manque d’outils en imagerie pour supporter les vétérinaires dans leur prise de
décision.
Dans cette recherche, nous nous intéressons à développer une méthode d’analyse pour
évaluer objectivement la structure interne des SDFTs à partir des examens cliniques. Deux
axes de recherche sont privilégiés :
− La simulation, dans des conditions réalistes, de la propagation des ondes ultrasonores à
travers la structure tendineuse, dans le but de reproduire l’aspect général clinique des
images échographiques. Les résultats de la simulation nous aideront à déduire
l’information sur le contenu structural observé sur les images cliniques des tendons sains
et lésés. Cette information servira ensuite à :
− L’élaboration de méthodes de segmentation de la structure interne et de la quantification
de la densité des faisceaux fibreux des tendons SDFTs à partir des examens cliniques.
La simulation nous a permis de noter d’une manière objective que les structures
hyperéchogènes observées sur les échographies des tendons normaux sont les résultats de la
rétrodiffusion des ondes ultrasonores sur les interstices qui entourent les faisceaux fibreux.
Les interstices qui génèrent les structures hyperéchogènes à une fréquence de 7,5 MHz sont
ceux qui ont des épaisseurs supérieures à la longueur d’onde acoustique λ (~256 μm) selon
l’axe de propagation des ondes ultrasonores. Les méthodes de segmentation utilisées se
résument en deux approches principales : une première méthode est dédiée exclusivement à
la segmentation des échographies du SDFT et combine une méthode de décompression
logarithmique et des opérations morphologiques. Une deuxième approche, plus générale, est
dédiée à la segmentation des échographies et des macrophotographies du SDFT. Elle se base
essentiellement sur un nouvel algorithme d’amincissement morphologique.
La quantification de la structure interne des tendons SDFT a permis de discerner
objectivement les tendons normaux des lésés. L’analyse statistique sur la densité des
faisceaux fibreux, évaluée à partir des examens cliniques sur des sites préférentiels des
SDFTs normaux a montré une faible densité sur le site distal. Cette analyse a été corroborée
par l’application de la même approche de segmentation et de quantification sur une base de
données d’images macrophotographiques des SDFTs. Cela peut traduire une faiblesse en
traction mécanique du site distal et expliquer la fréquence élevée des blessures sur ce site.
Ces résultats pourront éventuellement être adaptés à l’étude des tendons et des ligaments
chez l’humain.