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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Porcine urinary bladder matrix in an in vitro equine model of tenogenesis

Khatibzadeh, Sarah M. 22 August 2019 (has links)
Extracellular matrix (ECM) is responsible for tendon strength and elasticity. Healed tendon ECM lacks structural integrity, leading to reinjury. Porcine urinary bladder matrix (UBM) provides a scaffold and source of bioactive proteins to improve tissue healing, but has received limited attention for treating tendon injuries. The objective of this study was to evaluate the ability of UBM to induce matrix organization and tenogenesis using a novel in vitro model. We hypothesized that addition of UBM to tendon ECM hydrogels would improve matrix organization and cell differentiation. Hydrogels seeded with bone marrow cells (n = 6 adult horses) were cast using rat tail tendon ECM ± UBM, fixed under static tension and harvested at 7 and 21 days for construct contraction, cell viability, histology, biochemistry, and gene expression. By day 7, UBM constructs contracted significantly from baseline, whereas control constructs did not. Both control and UBM constructs contracted significantly by day 21. In both groups, cells remained viable over time and changed from round and randomly oriented to elongated along lines of tension with visible compaction of the ECM. There were no differences over time or between treatments for nuclear aspect ratio, DNA, or glycosaminoglycan content. Decorin, matrix metalloproteinase 13, and scleraxis expression increased significantly over time, but not in response to UBM treatment. Mohawk expression was constant over time. Cartilage oligomeric matrix protein expression decreased over time in both groups. Using a novel ECM hydrogel model, substantial matrix organization and cell differentiation occurred; however, the addition of UBM failed to induce greater matrix organization than tendon ECM alone. / Master of Science / Tendon injuries are common in horses and are painful and can be career- and life-ending. Tendons have a special structure and organization that enables them to withstand high tensile forces without permanent deformation. Injured tendons heal by forming stiff, disorganized scar tissue that makes the tendon more prone to re-injury. The lining of urinary bladders from pigs (UBM) provides a physical mesh and signaling factors that help heal injuries in a variety of tissues to a more normal state. However, UBM has not been evaluated in a laboratory model of tendon tissue formation to determine how it can help heal tendon injuries. Three-dimensional models of new tendon tissue formation (neotendons) were made with rat tail tendon matrix and stem cells collected from horse bone marrow. The neotendons were placed under steady tension for 3 weeks. The models were collected after 1 and 3 weeks to measure their width, numbers of live cells, cell and matrix organization, levels of tendon matrix components and expression of genes found in tendons. Most cells in the neotendons remained alive during the study period. Over time, UBM-treated and untreated neotendons became narrower compared to their starting width. The width of UBM-treated neotendons decreased faster than non-treated neontendons in the first week of the study. Cells became longer, narrower, and oriented along lines of tension. Expression of genes important in tendon development and structure either increased or was constant over time. UBM treatment did not change cell shape or increase levels of tendon-associated genes, DNA, or tendon matrix components. Our novel tendon model successfully created organized tendon-like tissue when placed under tension. However, UBM treatment did not improve formation of tendon-like tissue to a greater extent than controls.
102

Propriedades mecânicas de dois padrões de sutura e dois tipos de fios aplicados às tenorrafias de equinos / Mechanical properties of two patterns and two suture material applied in equine tenorrhaphies

Corrêa, Rodrigo Romero 11 May 2012 (has links)
As lesões traumáticas do membros que resultam em secções tendíneas são problemas comuns na clínica equina. Estas lesões podem ser tratadas de forma conservativa ou cirúrgica. Diversas complicações tem sido associadas às técnicas cirúrgicas, como ruptura do fio de sutura, ruptura do coto tendíneo suturado, infecções da ferida, entre outros. O objetivo do presente trabalho foi avaliar biomecanicamente a combinação entre os padrões de sutura locking loop duplo e locking loop simples com sutura de epitendão, com os fios de sutura polipropileno e poliglactina 910, ambos de número 2, visando estipular a melhor combinação entre as variáveis quando aplicadas ao tendão flexor digital profundo de equinos. Os corpos de prova foram submetidos a ensaios mecânicos de tração, onde determinaram-se valores de força mínima, força máxima e pico de força durante o afastamento de 3 milímetros entre os cotos suturados, além do afastamento observado entre os cotos durante o pico máximo de força. Quando avaliada a força máxima, observaram-se maiores valores (p0,05) nos grupos onde foi utilizado o padrão locking loop simples com sutura de epitendão, e também quando a sutura foi realizada com polipropileno. Para a força mínima, o padrão simples também se mostrou superior, não havendo diferença significativa quando variaram-se os fios de sutura. Quando avaliado o pico de força, as suturas duplas foram superiores, não havendo diferença estatística quando comparadas com a sutura simples realizada com polipropileno. Os padrões duplos permitiram maior afastamento que os padrões simples com sutura de epitendão. O padrão locking loop simples, com sutura de epitendão, atinge maiores valores de força enquanto o afastamento é de até 3 milímetros. Quando realizado com polipropileno, este padrão suporta maior carga do que quando realizado com poliglactina. / The traumatic lesions of the limbs that result in tendon sections are common problems in equine medicine. These lesions can be treated with clinical or surgical procedures. Several complications, as rupture of the suture material, rupture of the tendon extremity and wound infection have been associated with the technique. The objective of this study was evaluate biomechanically the locking loop suture and the locking loop with epitendon suture, when performed with polypropylene and polyglactin 910 suture material, number 2, looking for the best combination between the variables when applied to equine deep digital flexor tendon. The specimens was submitted to a strain test. Values of minimum strength, maximum strength and force peak were measured during 3 millimeters of separation between the tendon extremities, and the gap was observed between the tendon extremities during the maximum peak force. During maximum strength evaluation, the higher values (p0,05) were observed in groups which were used simple locking loop pattern associated with epitendon suture, and also when the suture was performed with polypropylene. For the minimum strength, the simple pattern was also better, showing no significant difference between the types of suture material. When the peak force was measured, the double sutures were better, and there was no statistic variation when compared with the suture performed with polypropilene in a simple pattern. The double patterns allowed higher separation than the simple patterns associated with epitendon suture. The simple locking loop pattern, with epitendon suture, reaches higher values of strength when there is 3 millimeters of separation. When performed with polypropylene, this pattern supports higher load than when performed with polyglactin.
103

Efeito sinérgico da associação exercício/aquecimento nas propriedades mecânicas e estruturais do tendão calcâneo / Synergistic effect of the combination exercise/heat on the mechanical and structural properties of the Achilles tendon

Rosa, Rubens dos Santos 19 March 2014 (has links)
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.
104

Estudo comparativo de sistemas a base de lasers, leds e ultra-som (US) de baixa intensidade no reparo tecidual em tendão calcâneo / Comparative study of Laser, LED and US systems of low intensity applied to tendon healing

Bastos, Jessica Lucia Neves 05 August 2008 (has links)
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.
105

Os efeitos do ultra-som terapêutico aplicado na fase precoce da cicatrização do tendão flexor. estudo biomecânico em tendões de coelho.

Romano, Cristiane Vitaliano Graminha 21 June 2001 (has links)
Foi realizado um estudo experimental dos efeitos do ultra-som terapêutico sobre a resistência à tração de tendões flexores em cicatrização, usando o tendão flexor dos dedos de coelho como modelo. Foram utilizados 25 coelhos fêmea, da raça Nova Zelândia, adultos jovens de 3 Kg de peso corporal médio. Todos os animais foram operados sob anestesia geral para terem o tendão flexor profundo do terceiro dedo da pata dianteira direita seccionado e imediatamente reparado com a técnica de Kessler. As patas operadas eram imobilizadas com uma órtese de material termoplástico durante todo o período do experimento (4 semanas) e os animais foram distribuídos em dois grupos ( A e B) de acordo com o tratamento pós-operatório. No grupo A (13 animais) todos os animais receberam uma aplicação diária de 6 minutos de duração de ultra-som pulsado (1:5), regulado para uma freqüência de 3 MHz e intensidade de 0,8 W/cm², por sete dias consecutivos começando do primeiro dia. O grupo B (12 animais) era apenas de controle. Quatro semanas mais tarde, os animais eram mortas e todo o tendão operado era ressecado, incluindo a junção miotendínea e o segmento distal, e submetidos aos testes de resistência à tração na máquina universal de ensaios. Gráficos das cargas versus a deformação foram obtidos, permitindo a análise dos parâmetros carga e deformação máximas, carga e deformação no limite de proporcionalidade e rigidez. Os resultados mostraram que não houve diferenças significantes entre os grupos A e B, levando à conclusão de que o ultra-som terapêutico não tem influência no curso do processo de cicatrização dos tendões, particularmente no que se refere à resistência mecânica. / An experimental study of the effects of the therapeutic ultrasound on the resistance to traction of healing flexor tendons carried out using the rabbit flexor tendon as model. Twenty five young adult female New Zeland rabbits of average 3 Kg body weight were used. All the animals were operated under general anesthetics to have the profundus flexor tendon of the third finger of the right forepaw divided and immediately repaired with Kessler technique. The operated on paw was immobilized with an orthesis made of thermoplastic material for the entire length of the experiment (four weeks) and the animals were divided in two groups (A and B), according to the postoperative treatment. In group A (13 animals) all animals received one 6 minutes daily application of pulsed ultrasound (1:5), set for 3 MHz frequence and 0,8 W/cm² intensity, for seven consecutive days beginning on the first postoperative day. Group B (12 animals) was for control only. Four weeks later, the animals were killed, the entire operated tendons were resected including the myotendinous junction and the distal segment and submitted to the test of resistance to traction in a universal testing machine. Load versus deformation graphs were obtained allowing for the analysis of the parameters maximum load and deformation, load and deformation in the limit of proportionality, and stiffness. The results showed that there was no significant difference between groups A and B, leading to the conclusion that therapeutic ultrasound does not influence the course of the tendon healing process, as refers to mechanical resistance.
106

Mudança nas propriedades passivas da unidade musculo-tendínea do tríceps sural durante 10 minutos de alongamento estático passivo

Borges, Mariana de Oliveira January 2018 (has links)
Introdução: os estudos sobre flexibilidade vêm tentando compreender quais propriedades explicam o aumento da amplitude de movimento (ADM), além do aumento de extensibilidade muscular. Propriedades mecânicas passivas de outros tipos de tecido, como o tendão, vêm sendo avaliadas, para entender a sua interferência no aumento da ADM. Desenho do estudo: o estudo foi do tipo ensaio clínico randomizado. Objetivos: analisar, minuto a minuto, o deslocamento da junção miotendínea (JMT) do músculo gastrocnêmio medial com o tendão do calcâneo e o torque passivo durante uma sessão de 10 minutos de alongamento estático passivo de flexores plantares, e analisar a mudança destas e de outras propriedades passivas mecânicas da unidade músculo-tendínea (UMT) do tríceps sural antes e após essa intervenção, verificando se estas mudanças perduram após 15, 30, 45 e 60 minutos após o protocolo de alongamento. Métodos: 30 participantes saudáveis foram divididos em grupo controle, o qual permaneceu em repouso, e experimental, o qual realizou uma sessão de 10 minutos de alongamento estático passivo no dinamômetro isocinético. Os participantes realizaram os testes de ADM, torque passivo, deslocamento da JMT e histerese antes e após a intervenção (0, 15, 30, 45 e 60 minutos). A partir dessas variáveis, foram calculadas as medidas de rigidez tendínea, muscular e da UMT. Resultados: Cinco participantes não permaneceram relaxados durante os testes e foram excluídos após análise dos dados eletromiográficos. 25 participantes foram incluídos na análise. Os resultados foram divididos em dois estudos diferentes. No primeiro estudo, apenas os 12 participantes do grupo experimental foram incluídos e, ao longo da intervenção, foi encontrada uma redução significativa do torque passivo, com a principal diferença ocorrendo nos minutos cinco e sete. No segundo estudo, foram comparados os indivíduos do grupo controle (n=13) e do grupo experimental (n=12), com um período de follow up de 60 minutos após a intervenção. A ADM aumentou e permaneceu aumentada até uma hora após a intervenção em ambos os grupos. As variáveis de deslocamento da JMT, rigidez muscular e histerese aumentaram em alguns momentos ao longo do tempo, sem diferença entre os grupos. A rigidez tendínea não apresentou diferença nem para grupo e nem para tempo. As variáveis de torque passivo e rigidez da UMT apresentaram uma interação significativa entre grupo e tempo, com uma redução das duas ao longo do tempo no grupo experimental. Conclusões: há uma redução de torque passivo ao longo de uma sessão de alongamento estático de 10 minutos dos flexores plantares de tornozelo, e fazer parte do grupo experimental influenciou no comportamento do torque passivo e da rigidez da UMT, levando a uma maior redução das mesmas para o grupo que realizou o alongamento. A ADM aumentou e permaneceu aumentada até uma hora após a intervenção. / Background: studies on flexibility have attempted to understand which properties explain increased range of motion (ROM), in addition to increased muscle extensibility. Mechanical and passive properties of other types of tissue, such tendon tissue, have been evaluated in order to understand their interference in increased ROM. Study Design: randomized clinical trial. Objectives: to analyze, minute by minute, myotendinous junction (MTJ) displacement of the medial gastrocnemius muscle with Achilles tendon and passive torque during a 10-minute passive static stretching of the ankle plantar flexors. To analyze, also, the time course change of these and other muscle-tendon unit (MTU) mechanical properties of the triceps surae before and after the intervention, verifying if the changes persist after 15, 30, 45 and 60 minutes after the stretching protocol. Methods: 30 healthy participants were divided into a control group, which remained at rest, and an experimental group, which performed a 10-minute passive static stretching on the isokinetic dynamometer. Participants performed tests of ROM, passive torque, MTJ displacement and hysteresis before and after the intervention (0, 15, 30, 45 and 60 minutes). From these variables, the measures of tendinous, muscular and MTU stiffness were calculated. Results: Five participants did not remain relaxed during the test and were excluded after electromyographic data analysis. 25 participants were included in the analysis. Results were divided into two different studies. In the first one, only 12 participants of experimental group were included and during the intervention, a significant reduction of the passive torque was found, with the main difference occurring in minutes five and seven. In the second study, individuals from control group (n=13) and experimental group (n=12) were compared, with a 60 minute follow-up period after the intervention. ADM increased and remained increased up to one hour after the intervention. The variables of MTJ displacement, muscular stiffness and hysteresis increased at some moments over time, with no difference between the groups. The tendinous stiffness showed no difference neither for group nor for time. The variables of passive torque and MTU stiffness showed a significant interaction between group and time, with a reduction of the two over time in the experimental group. Conclusions: passive torque decreased throughout a 10-minute passive static stretching of the ankle plantar flexors, and being part of the experimental group influenced the behavior of the passive torque and the MTU stiffness, leading to a greater reduction of the same for the group who performed the stretching.
107

Propriedades mecânicas de dois padrões de sutura e dois tipos de fios aplicados às tenorrafias de equinos / Mechanical properties of two patterns and two suture material applied in equine tenorrhaphies

Rodrigo Romero Corrêa 11 May 2012 (has links)
As lesões traumáticas do membros que resultam em secções tendíneas são problemas comuns na clínica equina. Estas lesões podem ser tratadas de forma conservativa ou cirúrgica. Diversas complicações tem sido associadas às técnicas cirúrgicas, como ruptura do fio de sutura, ruptura do coto tendíneo suturado, infecções da ferida, entre outros. O objetivo do presente trabalho foi avaliar biomecanicamente a combinação entre os padrões de sutura locking loop duplo e locking loop simples com sutura de epitendão, com os fios de sutura polipropileno e poliglactina 910, ambos de número 2, visando estipular a melhor combinação entre as variáveis quando aplicadas ao tendão flexor digital profundo de equinos. Os corpos de prova foram submetidos a ensaios mecânicos de tração, onde determinaram-se valores de força mínima, força máxima e pico de força durante o afastamento de 3 milímetros entre os cotos suturados, além do afastamento observado entre os cotos durante o pico máximo de força. Quando avaliada a força máxima, observaram-se maiores valores (p0,05) nos grupos onde foi utilizado o padrão locking loop simples com sutura de epitendão, e também quando a sutura foi realizada com polipropileno. Para a força mínima, o padrão simples também se mostrou superior, não havendo diferença significativa quando variaram-se os fios de sutura. Quando avaliado o pico de força, as suturas duplas foram superiores, não havendo diferença estatística quando comparadas com a sutura simples realizada com polipropileno. Os padrões duplos permitiram maior afastamento que os padrões simples com sutura de epitendão. O padrão locking loop simples, com sutura de epitendão, atinge maiores valores de força enquanto o afastamento é de até 3 milímetros. Quando realizado com polipropileno, este padrão suporta maior carga do que quando realizado com poliglactina. / The traumatic lesions of the limbs that result in tendon sections are common problems in equine medicine. These lesions can be treated with clinical or surgical procedures. Several complications, as rupture of the suture material, rupture of the tendon extremity and wound infection have been associated with the technique. The objective of this study was evaluate biomechanically the locking loop suture and the locking loop with epitendon suture, when performed with polypropylene and polyglactin 910 suture material, number 2, looking for the best combination between the variables when applied to equine deep digital flexor tendon. The specimens was submitted to a strain test. Values of minimum strength, maximum strength and force peak were measured during 3 millimeters of separation between the tendon extremities, and the gap was observed between the tendon extremities during the maximum peak force. During maximum strength evaluation, the higher values (p0,05) were observed in groups which were used simple locking loop pattern associated with epitendon suture, and also when the suture was performed with polypropylene. For the minimum strength, the simple pattern was also better, showing no significant difference between the types of suture material. When the peak force was measured, the double sutures were better, and there was no statistic variation when compared with the suture performed with polypropilene in a simple pattern. The double patterns allowed higher separation than the simple patterns associated with epitendon suture. The simple locking loop pattern, with epitendon suture, reaches higher values of strength when there is 3 millimeters of separation. When performed with polypropylene, this pattern supports higher load than when performed with polyglactin.
108

Ultrasound imaging of finger tendons at the bedside in the emergency department: a pilot study to assess whether it is a feasible and useful investigation

Hall, Ann Charlotte Unknown Date (has links)
The interplay of structures in the finger that facilitate movement is complex and not yet fully understood. Subtle finger injuries are often missed during the initial assessment in the Emergency Department, because clinical examination of the acutely injured hand can be difficult. The consequences of unrecognized finger injuries can be devastating for the patient. Ultrasound imaging of tendons is a useful investigative tool although little has been published regarding the reliability of finger tendon measurements. The overall objective of this project was to establish if bedside ultrasound imaging of tendons was possible and useful in the setting of acute injury. The project was divided into two studies.In the first study, 65 apparently normal volunteers were scanned to allow the principal investigator to practise and refine the ultrasound technique. The dimensions of the Extensor Digitorum Longus and two flexor tendons combined (Flexor Digitorum Profundus and Flexor Digitorum Superficialis) were measured in both transverse and longitudinal sections. Fifteen of the volunteers had their left middle fingers scanned twice within 48 hours to establish the test to retest reliability of tendon measurement. The established scanning technique was simple to perform and the scans, including both static and real time images, were completed within five minutes. All volunteers were able to tolerate a full scan. Measurement of tendon width showed fair to good reliability (Intra class correlation [ICC] of flexor tendons = 0.66, ICC of extensor tendon = 0.54). However measurement of the depth of all the tendons was unreliable test to retest (ICC < 0.37).In the second study, 30 patients who presented to the Emergency Department at Lismore Base Hospital with hand injuries were scanned for evidence of tendon injury and tendon gliding restriction. The patient’s ability to tolerate ultrasound examination was investigated. The scan findings were compared with the clinical findings and then to the operation report or to the patient’s self reported outcome, one month after injury.Patients were willing to undergo ultrasound examination regardless of the extent of their injury. There was a significant difference (p = 0.04) in scan tolerance related to the site of injury with 50% of those with extensor surface injuries having completed scans in comparison to 36% with flexor surface injuries and 9.1% of finger tip injuries. Injury mechanism was not related to scan tolerance.Excluding a partial tendon laceration was technically difficult due to the presence of anisotropy artefact. However, all complete tendon lacerations were successfully identified prior to surgery. The gliding of the tendons was easy to visualize and abnormal gliding was found to be a marker of tendon injury.The overall results show that ultrasound imaging of finger tendons at the bedside in the Emergency Department is a feasible examination to perform. The addition of ultrasound examination, however, did not identify any cases of tendon injury not already suspected on routine clinical examination.Therefore, this pilot study suggests that routine use of ultrasound examination to detect finger tendon injury in the Emergency Department setting will not prove to be a useful investigation. There may be a role for ultrasound as a screening tool as the gliding of normal tendons differed noticeably from the gliding of injured tendons. The presence of normal tendon gliding may be helpful in identifying those patients that are safe to be discharged from the Emergency Department without further evaluation.
109

Robotic Guidance: Velocity Profile Symmetry and Online Feedback Use during Manual Aiming

Srubiski, Shirley Luba 27 November 2012 (has links)
The current study evaluated whether robotic guidance can influence movement planning and/or the use of online proprioceptive feedback. Participants were divided into three groups wherein they practiced an aiming task unassisted or via a robotic device that led them through a trajectory with an asymmetric or symmetric velocity profile. Baseline performance was measured prior to training and a post-test included control and tendon vibration trials. Temporal, spatial, and kinematic variables were used to assess planning and online control mechanisms. Results indicated that tendon vibration altered the way individuals planned their movements and used online sensory feedback. Robotic-guided groups appeared to use online feedback to a lesser extent than the unassisted group during tendon vibration trials, based on kinematic data. Individuals may become less inclined to use erroneous proprioceptive feedback following robotic guidance, supporting the potential benefit of robotics in neuro-motor rehabilitation for those with proprioceptive deficits.
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Effets d'un programme en électrostimulation suite à une rupture du tendon d'Achille

Veillette, Pierre-Marc January 2008 (has links) (PDF)
L'électrostimulation est une méthode de mieux en mieux comprise en physiologie humaine. D'un autre côté, la rupture du tendon d'Achille amène chez la personne l'ayant subi une perte de force et de volume chronique. L'objet de ce projet fut d'observer si la force et le volume d'une jambe peuvent être améliorés avec l'aide d'un entraînement en électrostimulation. 9 sujets divisés en deux groupes (expérimental = 6, témoin = 3) ont subit un pré-test où fut mesurée leur force de contraction concentrique, excentrique et isométrique lors du mouvement de flexion plantaire. Le volume de la jambe fut également mesuré par la prise de la circonférence du mollet au niveau du ventre des gastrocnémiens. Le groupe expérimental a suivi un entraînement en électrostimulation des fléchisseurs plantaires d'une seule jambe à une fréquence de 50 Hz, 5 secondes de travail, 15 secondes de repos pendant 15 minutes. L'entraînement eu lieu 3 fois par semaine durant 8 semaines. Le groupe témoin ne suivit aucun entraînement particulier durant les 8 semaines. Un test identique au pré test fut repassé 4 semaines (test intermédiaire) après le début de l'entraînement (ou du non-entraînement pour le groupe témoin). L'ensemble des mesures de force et de volume (post-test) fut repris après les 8 semaines d'entraînement (ou de non entraînement pour le groupe témoin). Une analyse comparative de la force et du volume des deux jambes avant et après la période de 8 semaines fut effectuée pour les deux groupes. Nous avons observé une augmentation significative de force concentrique et isométrique pour la jambe entraînée par électrostimulation du groupe expérimental. Aucun autre gain de force ne fut significatif pour les autres groupes. Aucun gain de volume ne fut significatif pour aucun groupe. Ces résultats laissent croire que l'électrostimulation peut améliorer la force d'une jambe et que cette technique pourrait être employée pour aider ceux ayant subi une rupture du tendon d'Achille. D'autres recherches sont nécessaires sur des personnes ayant subi une rupture du tendon d'Achille pour observer si un gain de volume serait possible et si les paramètres de stimulation pourraient être améliorés. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Électrostimulation, Rupture tendon d'Achille, Triceps sural, Force.

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