Orientador: Alberto Cliquet Junior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-21T16:15:28Z (GMT). No. of bitstreams: 1 Alves_CarolinaLinsHenrique_M.pdf: 1344793 bytes, checksum: a8898223919974f480976745b55f4b9b (MD5) Previous issue date: 2012 / Resumo: As rupturas crônicas do tendão do calcâneo são desafios cirúrgicos e apresentam consequências na marcha. O propósito deste estudo foi avaliar parâmetros cinéticos e cinemáticos da articulação do tornozelo em treze pacientes diagnosticados com rupturas de tendão do calcâneo e tratados cirurgicamente através da técnica de enxerto livre do tendão do músculo semitendíneo. Os dados foram colhidos seis meses (6M) e doze meses (12M) após o procedimento através de plataforma de força enquanto os movimentos eram gravados por seis câmeras infravermelhas. Dois grupos foram submetidos à análise da marcha: grupo Paciente (subgrupos: pé Normal 6M, pé Normal 12M, pé Operado 6M e pé Operado 12M) e grupo Controle. As variáveis cinemáticas analisadas incluíram velocidade, cadência, comprimento do passo, porcentagem de fase de apoio e amplitude de movimento do tornozelo nos planos frontal e sagital. Os dados cinéticos foram obtidos pelo momento articular em diferentes fases do ciclo da marcha. No questionário de função AOFAS aplicado ao grupo Paciente observou-se aumento significativo de 68,5 pontos para 85,2 pontos (p=0,0215) na escala de 0 a 100 pontos, entre as coletas de seis e doze meses. Velocidade, cadência e comprimento do passo do grupo Paciente foram menores que o grupo Controle. A porcentagem da fase de apoio foi maior no subgrupo pé Normal 6M quando comparado ao grupo Controle. Nos dados cinemáticos a amplitude de movimento do tornozelo na fase de apoio aumentou entre os subgrupos pé Operado 6M e pé Operado 12M (p=0,0255) demonstrando efeito de tempo. Durante a fase de balanço a amplitude de movimento do tornozelo foi menor nos subgrupos pé Operado 6M/12M quando comparados aos subgrupos pé Normal 6M/12M demonstrando efeito de lado (p=0,0255). Os subgrupos pé Operado 6M e pé Operado 12M demonstraram diferença significativa quando comparado com grupo Controle (p=0,0240 e p=0,0414 respectivamente). A amplitude de movimento de inversão e eversão também apresentou efeito de tempo entre os mesmos grupos (p=0, 0059) citados anteriormente. Os dados cinéticos não apresentaram diferença significativa. O presente estudo mostrou grande proximidade entre o grupo Paciente e o grupo Controle, além da melhora entre os subgrupos pé Operado 6M e pé Operado 12M / Abstract: Chronic rupture of the Achilles tendon is a surgical challenge and has consequences in gait. The purpose of this study was to evaluate the kinetic and kinematic parameters of the ankle joint in 13 patients diagnosed with Achilles tendon rupture and operated using a free semitendinosus tendon graft. The data were collected six (6M) and twelve (12M) months after surgery in a force platform while the movements were recorded by six infrared cameras. Two groups were analyzed: group Patient (organized in 4 subgroups: Normal foot 6M, Normal foot 12M, Operated foot 6M, Operated foot 12M) and group Control. The kinematic variables analysed included speed, cadence, step length, percentage of stance phase and range of movement (ROM) of the ankle joint in sagital and frontal plane. Kinetic data were obtained by joint moment in different phases of gait cycle. In the functional questionnaire AOFAS applied to the group Patient it was observed a significant increase from 68,5 (±18,7) to 85,2 (±18,0) (p=0,0215) in a scale ranging from 0 to 100 within six and twelve months . Speed, cadence and step length of the group Patient were lower than Control group. The percentage in stance phase was higher for subgroup Normal foot 6M compared to the Control group. For kinematic data, the range of movement of the ankle in stance phase increased between Operated foot 6M and Operated foot 12M, showing an effect of time. During swing phase, the ankle ROM was lower in subgroups Operated foot 6M/12M when compared to subgroups Normal foot 6M/12M, showing effect of side (p=0,0255). The subgroups Operated foot 6M and Operated foot 12M demonstrated statistical difference when compared to Control group (p=0,0240 and p=0,0414, respectively). ROM of inversion and eversion presented effect of time among the same subgroups (p=0,0059) cited before. There were no statistic differences on kinetic data between groups. This study showed close proximity between group Patient and Control group and better results between subgroups Operated foot 6M and Operated foot 12M / Mestrado / Fisiopatologia Cirúrgica / Mestra em Ciências

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 tendineuses. / Tendon 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.

The Achilles tendon is the largest tendon in the human body, which elastically stores and releases energy to facilitate walking and running. Tendons can suffer from a range of pathologies, most notably that of complete rupture, which affects athletes, physically active workers and the aged. There is a growing demand for in vivo methods of objectively measuring tendon health for aiding diagnosis, monitoring therapy and for assessment of new treatments. Knowledge of the changes in mechanical properties during the healing process is also limited and new methods to accurately and consistently estimate these could provide insights into the healing process and guide future research efforts. This thesis presents the development and use of 2D ultrasound elastography, a quantitative strain estimation imaging technique, as a tool to measure changes in the tensile mechanical properties of the Achilles tendon. This technique performs frame-to-frame block matching of image texture to track motion in an ultrasound signal sequence and create a strain estimation field from the spatial derivative of the motion. Elastography in the image-lateral direction of sagittal plane scans is of particular interest as this is in line with the longitudinal axis of the tendon, but presents extra accuracy issues from out of plane motion and lower image spatial resolution. Tendon rupture also presents unique problems to image acquisition and analysis- patient pain and safety are important considerations and disruption of the ultrasound texture can make 2D motion tracking more difficult. A new 2D elastography block matching algorithm, named `AutoQual', was developed to enable accurate tracking of motion in the image-lateral direction and reduce the impact of artefacts and errors common with damaged Achilles tendons image sequences. It was shown to outperform a multiscale block matching method when tested using ultrasound sequences from in vivo and gelatine phantom experiments. The input parameters of this algorithm were then optimised using the phantom data for benchmarking. The AutoQual algorithm was then used to analyse ultrasound sequences from a 24-week longitudinal study of 21 subjects with ruptured Achilles tendons to assess lateral, axial and principal strains during controlled passive motion of the foot or axial palpation of the ultrasound probe. Lateral and principal strains from controlled dorsiflexion were shown to be more repeatable and more sensitive to change than axial strains with manual palpation. This experience with lateral strain imaging from ruptured Achilles tendons gave an increased knowledge of the strain imaging artefacts and features that can occur. These are described in detail in order that they may be further mitigated in quantitative analysis by optimising acquisition protocols, further amendment of the block tracking algorithm, or exclusion of erroneous areas when selecting regions of interest. Regularisation is a potential solution to some common artefacts such as discontinuities from poor tracking in shadow regions. Regularisation of the lateral displacement fields is investigated using 2D bicubic smoothing splines. The regularisation parameters used are shown to have minimal effect on quantitative analysis and can aid visual clarity or reduce artefacts within certain settings. However, regularisation was also shown to cause large errors when parameters were set more aggressively. Finally, it is identified that cumulative lateral strain measurement of the Achilles and other tendons is feasible but that future work is needed to further improve the quality of force and cross sectional area measurements in order to infer mechanical properties accurately. Repeatable high force motion protocols also need to be developed to measure healthy tendons and to ensure comparable results between different patients and research groups.

M.Tech.

Fibrotic diseases account for an estimated 45% of the total number of deaths in the developed world (Wynn 2007). Tendons are an excellent model for studying the dysregulated response which leads to fibrosis, as tendons have an organized, parallel matrix, in which tissue defects could easily be distinguished. Wong et al. (2006b) demonstrated the presence of a bell-shaped region around sutures in tendons that was devoid of cells in histological sections. The mechanisms of the formation of this acellular zone, that was also noted in cornea and cartilage (Matsuda et al. 1999; Hunziker and Stähli 2008), were unknown. It was hypothesized that the acellular zone was formed by cell death and that suturing caused alterations to the extracellular matrix of sutured regions of tendon, which made the acellular zone refractory to cellular re-population. The acellular zone was tracked in sutured tendons for up to a year to determine the temporal properties of the acellular zone. Electron microscopic and time lapse studies were carried out to determine if the acellular zone formed by cell migration or cell death. Microarray analysis was conduced to confirm this and to reveal potential molecular targets for future studies. The extracellular matrix of sutured tendons was studied by electron, atomic, scanning and polarized light microscopy and mechanical measurements were obtained using nanoindentation. It was concluded that the acellular zone formed within 24 hours and persisted for up to a year. Tension and size of the suture's grasp were also shown to be important for acellular zone formation. Cell death was the main effector of acellular zone formation. Microarray analysis showed evidence of upregulation of inflammatory mediators and programmed necrosis pathways. The sutured extracellular matrix was denser, more disorganized and had a lower Young's modulus than unsutured regions of the same tendon. These differences in the properties of the extracellular matrix of sutured tendons may be the cause of the persistence of the acellular zone.

Um dos recursos mais utilizados no processo de reparo de lesões tendíneas é o laser que demonstrou ter resultados satisfatórios quando se buscam efeitos antiinflamatório e cicatrizante. No entanto, por requerer uma tecnologia de alto custo, um outro tipo de fototerapia vem sendo buscado, como o diodo emissor de luz, LED. Porém, o número de pesquisas realizadas para a determinação segura de seus efeitos terapêuticos ainda é muito pequeno, inviabilizando uma proposta de protocolo para adoção do LED. Um outro recurso também utilizado durante a reabilitação de lesões tendíneas, é o ultra-som pulsado de baixa intensidade (LIPUS). Trabalhos realizados até o momento mostram alterações satisfatórias quanto à deposição e alinhamento das fibras de colágeno. Este estudo objetiva testar comparativamente a eficácia da aplicação de LEDs 630 nm e 830 nm em relação à terapia laser de baixa intensidade (LILT), com laser de 685 nm e 830 nm, e à terapia com LIPUS em tendão calcâneo parcialmente lesado. Foram utilizados 56 ratos Wistar, submetidos à lesão mecânica parcial do tendão calcâneo. A análise da evolução do processo foi realizada através da microscopia de polarização. Os resultados mostraram uma real eficácia dos tratamentos com LEDs e lasers, e uma ineficácia do tratamento à base de US. Nosso estudo sugere que uma boa organização e um bom alinhamento das fibras de colágeno são conseguidos no processo de reparo de lesões tendíneas através de aplicações à base de LED 880 nm e laser 630 nm, os quais se mostraram mais eficazes. No entanto, outras pesquisas na área se fazem necessárias para uma determinação segura e eficaz dos protocolos de tratamento utilizando essa modalidade de fototerapia. / Laser is one of the most effective resources of treatment for tendinous injury when anti-inflammatory and cicatrizing effects are wanted. However, it is considered an expensive treatment and so, an alternative and cheaper light therapy as effective as it has been searched and the light emitting diodes, LEDs, are a promising candidate for it. Results from the studies already done have been useful to predict the possible effects of LED on the injured tissues, but are not enough to establish a treatment protocol that guarantees its recommendation as a substitute therapeutic tool for tendinous injury treatment. Another promising resource for tendinous injury healing is the ultra-sound of low intensity (LIPUS). Studies done until the present moment have shown satisfactory results when deposition and alignments of collagens fibers are wanted. The aim of this study was to compare the effects of laser, light emitting diodes (LEDs) and ultra-sound of low intensity on the treatment of Achilles tendon of albino rats, Wistar lineage, exposed to mechanical trauma. The experimental model consisted of a partial mechanical lesion of the right Achilles tendon of 56 rats, which were divided in 6 groups, 5 with 10 animals and one, the control group, with 6. One hour after the lesion, the injured animals received the respective applications of laser, LED or US, and the same procedure was repeated each 24 h. The healing process and the deposition were evaluated by analyze of the alignment of collagens fibers through polarization microscopy. The results showed a real efficiency of treatments based on LEDs and lasers, but the treatment based on US was inefficient. Applications of laser at 830 and LED 880 nm were more efficient when the aim is a good organization and alignment of the collagen fibers on tendon healing. However more research is needed for a safety and more efficient determination of a protocol.

O aquecimento terapêutico e o treinamento com saltos verticais são modalidades de escolha para tratamentos nas várias áreas da medicina e da fisioterapia. Na literatura poucos estudos avaliaram a resistência do tendão calcâneo pós-aquecimento, principalmente em tecidos aquecidos a temperaturas elevadas (42 e 45°C). Este estudo teve o objetivo de comparar certas propriedades mecânicas do tendão calcâneo de ratos como: força no limite de resistência máxima (N), rigidez (N/m) e energia absorvida até o ponto de ruptura (mJ), após o aquecimento induzido in vivo por convecção associado ao exercício físico (saltos verticais) e posteriormente investigar quantitativamente e qualitativamente as alterações estruturais na proteína colágeno presente no tendão, por meio de análises histológicas (hematoxilina e eosina, picro-sirius), força atômica (AFM) e birrefringência. No presente estudo foram utilizados 35 Ratos Albinus da Raça Wistar, todos machos divididos em 7 grupos (grupo controle GC, I, II, III, IV, V e VI). O GC foi utilizado exclusivamente para análises histológicas, os grupos I (sem alteração térmica), III (42°C) e V (45°C) não passaram por exercícios físicos, os grupos II (sem alteração térmica), IV(42°C) e VI (45°C) passaram por exercícios físicos (saltos verticais) e todos os grupos passaram por ensaio mecânico de tração. De uma maneira generalizada os resultados para as análises mostraram uma diferença do grupo controle GC, I, II em relação aos grupos III, IV, V e VI, o que fez perceber que em temperaturas elevadas há danos no tecido tendíneo e em temperaturas iguais e ou acima de 42°C e 45°C associado ao exercício físico de saltos verticais o dano acentua-se. Há um início de danos ao tecido tendíneo, acentuando-se na temperatura de 45°C e os eventos constatados nas análises histológicas foram comprovados nos resultados dos ensaios mecânicos de tração. / Therapeutic heating and vertical jumps are training modalities of choice for treatment in various areas of medicine and physiotherapy. In the literature, few studies have evaluated the resistance of the Achilles tendon post-heating, especially in tissues heated to high temperatures (42 to 45°C). This study aims to compare certain mechanical properties of the Achilles tendon of rats as: strength in the limit of maximum resistance (N), stiffness (N/m) and energy absorbed to the point of rupture (mJ) after heat induction in vivo by convection associated with exercise (vertical jumps)and subsequently investigate qualitatively and quantitatively the structural changes in collagen protein present in the tendon by histological analysis (hematoxylin and eosin, picro-sirius red), atomic force (AFM) and birefringence. The present study used 35 Wistar rats, all males divided into 7 groups (control group GC, I, II, III, IV, V e VI). GC was used exclusively for histological analysis, the group I (no thermal alteration), III (42°C) and V (45°C) did not undergo physical exercises, groups II (without thermal alteration), IV (42°C) and VI (45°C) underwent exercise (vertical jumps) and all groups underwent mechanical tests. The results for the analyzes showed a difference between the GC, I, II groups in relation to III, IV, V and VI, showing that at elevated temperatures occurred a damage in tendon tissue and for temperatures equal or above 42°C and 45°C associated with the exercise of vertical jumps the damage is accentuated. There is an early tissue damage, with a peak temperature of 45°C and the events recorded in the histologic analyses were confirmed in the results of tensile test.

Introducción: Determinar la asociación entre el ángulo de inclinación del tendón patelar (AITP) y la presencia de dolor anterior de rodilla (DAR), así como conocer la prevalencia de DAR en deportistas universitarios. Material y métodos: Estudio de corte transversal en 143 deportistas universitarios. La presencia de DAR se detectó usando la Anterior Knee Pain Scale de Kujala y se calculó el AITP analizando una fotografía de ambas piernas con el programa Kinovea ®. Cada rodilla se consideró como una muestra. La razón de prevalencia entre el DAR y el AITP se calculó usando regresión de Poisson robusta. Resultados: Se evaluaron 143 sujetos, por tanto, 286 rodillas, donde 176 (61.5%) presentaban DAR. El AITP se clasificó en cuartiles. Para el análisis se unió el segundo y tercer cuartil, por lo que se obtuvo un cuartil medio (9°y 14°).Se encontró que un AITP menor a 9° tiene 1,34 (IC95%; 1,09-1,65) más probabilidad de tener DAR, y un AITP mayor a 14° tiene 1,35 (IC95%; 1,09-1,69) más probabilidades. Conclusiones: Los deportistas con un AIPT menor a 9° o mayor a 14° tienen mayor probabilidad de presentar DAR. Se recomienda que el profesional considere el ángulo de inclinación del tendón patelar en su evaluación. / Introduction: To determine the association between patellar tendon angle (AITP) and the presence of anterior knee pain (DAR) and the prevalence of DAR in college athletes. Materials and methods: Cross-sectional study of college athletes. The presence of DAR was detected using the Anterior Knee Pain Scale by Kujala and AITP was calculated by analyzing a photograph of both legs with Kinovea program ®. Each knee was considered as a sample. The prevalence ratio between the DAR and the AITP was calculated using Poisson regression robust Results: 143 subjects were evaluated, therefore, 286 knees, where 176 (61.5%) had anterior knee pain (DAR). The AITP was ranked in quartiles. To analyze was joined second and third quartile so was obtained a midquartile (9° and 14°). It was found that AITP fewer than 9° is 1.34 (95% CI, 1.09 - 1.65) more likely to have DAR, and AITP greater than 14° is 1.35 (95% CI; 1,09- 1.69) more likely. Conclusions: Athletes with AITP fewer than 9 ° or greater than 14 ° are more likely to have DAR. It is recommended that the professional considers the inclination patellar tendon angle in the evaluation / Tesis

Treatment of acute Achilles tendon ruptures has long been controversial. Several treatment options exist for patient with variable harms and benefits to each. Recognizing that decision of treatment option is preference-sensitive, this thesis focused on updating the current literature on Achilles tendon rupture management to facilitate the creation of a patient decision aid. A network meta-analysis of all treatment options for acute Achilles tendon ruptures was performed. Results demonstrated that minimally invasive surgery options were associated with lower complications and lower complications requiring surgery. Return to sport was similar amongst all treatment groups. With guidance from the Ottawa Decision Support Framework and the International Patient Decision Aid Standards, a three-tiered protocol for development, alpha testing and field-testing a novel patient decision aid is outlined next. The patient decision aid will be reviewed and revised iteratively by multi-disciplinary steering group. This protocol will act as a framework for further orthopaedic patient decision aid development.

The time it takes an athlete to recover from an injury can be highly influenced by training procedures as well as the medical care and physical therapy received. When an injury occurs to the muscles or tendons of an athlete, it is desirable to cool the muscles and tendons within the body to reduce inflammation, thereby reducing the recovery time. Consequently, finding a method of treatment that is effective in reducing tendon temperatures is beneficial to increasing the speed at which the athlete is able to recover. In this project, Bayesian inference with Gaussian processes will be used to model the effect that different treatments have in reducing tendon temperature within the ankle. Gaussian processes provide a powerful methodology for modeling data that exhibit complex characteristics such as nonlinear behavior while retaining mathematical simplicity.