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The purpose of this dissertation was to study the effects of graft pretension in anterior cruciate ligament (ACL) reconstruction through a series of experiments. First, an in vitro study of 5 human knees was conducted to determine if intact joint kinematics could be restored when using the ideal graft - the intrinsic ACL. The ACL tibial insertion site was freed, and pretensions of 0, 10, 20, 30, and 40 N were applied to the ligament using a custom designed load cell connection. Kinematics during a simulated active extension were compared to those of the intact knee. Intact knee kinematics were not restored. Pretensions that best restored tibial anterior/posterior translation and internal/external rotation ranged from 0-40 N. Furthermore, the pretensions that best restored these kinematic variables were widely disparate in two specimens. Second, the in vitro kinematics during a simulated active extension of human and porcine knees were compared and contrasted both prior to and following transection of the ACL. The ACL limited: (1) tibial anterior translation in both species, (2) tibial internal rotation in humans, and (3) tibial external rotation in pigs. Differences in kinematic patterns for tibial internal/external rotation and abduction/adduction between the species was explained by requirements for biped and quadruped stances. Third, the mechanical characteristics of porcine patellar tendon (PT) were investigated by uniaxial tensile testing at two strain rates. Patella-PT-tibia complexes from freshly sacrificed skeletally immature and mature animals were loaded to failure at elongation rates of 20 and 200 mm/min. Both strain rate and skeletal maturity significantly affected failure mode, tangent modulus, and ultimate stress of the tendons, and hence are important considerations in the mechanical evaluation of porcine PT. Fourth, ACL reconstructions were performed using pretensions of 10 or 20 N in an in vivo porcine model with a specially designed load cell/telemetry system to monitor graft load. Graft pretension was seen to increase during fixation with interference screws. Following sacrifice at 4 weeks, tissues were mechanically, histologically, and biochemically analyzed. A pretension of 20 N resulted in a tissue more similar to the intrinsic ACL. / Ph. D.

INTRODUÇÃO: O plasma rico em plaquetas (PRP) é utilizado em medicina esportiva para aumentar e acelerar o processo de reparação tecidual em lesões tendineas e ligamentares, no intuito de proporcionar um retorno mais rápido às atividades esportivas. No entanto faltam estudos com alto nível de evidência comprovando sua eficácia no tratamento destas lesões. Com o objetivo de estudar o efeito da aplicação do PRP no sitio doador de enxerto do ligamento da patela para reconstrução do ligamento cruzado anterior (LCA), realizamos ressonância magnética aos seis meses de pós-operatório para avaliar o ligamento da patela. Também aplicamos questionários de função do joelho e realizamos teste isocinético após seis meses da cirurgia. MÉTODOS: O presente estudo prospectivo, randomizado, avaliador cego incluiu 27 pacientes. Comparamos doze pacientes em que foi utilizado o PRP no defeito criado no terço central do ligamento da patela para retirada de enxerto com quinze pacientes do grupo controle. Aos seis meses de cirurgia realizamos ressonância magnética, em que foi avaliada a área não regenerada do defeito no terço central do ligamento da patela, a área de secção transversa do ligamento e a altura da patela pelo índice de Insall- Salvati. Realizamos teste isocinético e aplicamos questionários específicos de função do joelho. Quantificamos a dor pós-operatória imediata com escala visual analógica (EVA) de dor. RESULTADOS: Aos seis meses de pós-operatório a área não regenerada do defeito no terço central do ligamento da patela foi 4,95 mm2 no grupo PRP e 9,38 mm2 no grupo controle (p=0,046, teste t de Student). A área de secção transversa do ligamento da patela no grupo PRP foi de 173,05 mm2 e no grupo controle 176,29 mm2 (p=0,856). O índice de Insall-Salvati nos grupos PRP e controle foi de 1,04 e 1,06, respectivamente (p=0,808). Não houve diferença entre os grupos nos resultados dos questionários e teste isocinético. Nos pacientes em que foi utilizado o PRP houve menos dor pós-operatória imediata (p=0,02). CONCLUSÃO: Concluímos, nessa amostra, que o uso do PRP no defeito do terço central do ligamento da patela na reconstrução do LCA, nos primeiros seis meses; determinou maior regeneração do defeito; diminuiu a intensidade da dor pós-operatória imediata; não ocasionou alterações estruturais na avaliação por ressonância magnética; e não modificou os resultados clínicos e funcionais da cirurgia / INTRODUCTION: Platelet-rich plasma (PRP) has been used in sports medicine to improve and accelerate ligaments and tendons healing, in an effort to provide a faster return to sports activities. However there is a lack of high evidence level studies to support its use. With the purpose to study the effect of PRP, patellar ligament was evaluated six months after harvesting its central third with magnetic resonance imaging (MRI). We also applied specific questionnaires of knee function and isokinetic testing. METHODS: This blinded, randomized, prospective study included 27 patients. Twelve patients in whom we added PRP in the patellar ligament after harvesting its central third for ACL reconstruction were compared to fifteen patients in the control group. After six months we evaluated the non-regenerated area of the patellar ligament, the cross section area of the patellar ligament and its length (Insall-Salvati index) with MRI. We also evaluated the results of isokinetic testing and specific questionnaires of knee function. Immediate post-operative pain was evaluated with visual analogical scale (VAS) score. RESULTS: The non-regenerated area of the patellar ligament was 4,95 mm2 in the PRP group and 9,35 mm2 in the control group (p=0,046 test). The cross section area of the patellar ligament in the PRP group was 173,05 mm2 and in the control group 176,29 mm2 (p=0,856). The Insall- Salvati index in the PRP and control group was 1,04 and 1,06, respectively (p=0,806). There was no difference between the groups in the questionnaires and isokinetic testing results. PRP group patients had less post-operative pain (p=0,02). CONCLUSION: We concluded, in this sample, that the use of PRP in the patellar ligament after harvesting its central third for ACL reconstruction, in the first six months: improved the ligament regeneration; reduced the intensity of immediate post-operative pain; did not cause structural changes in the patellar ligament in MRI; and did not modify the clinical and functional results of the procedure

O mal alinhamento do membro pélvico de cães contribui para o desenvolvimento ósseo anormal e deslocamento medial ou lateral do aparelho extensor do quadríceps. De acordo com o aumento da incidência da luxação de patela em cães de médio e grande porte, o estudo do alinhamento do membro pélvico e das deformidades ósseas associadas recebeu destaque. Assim, o conhecimento do eixo mecânico e do alinhamento do membro pélvico, bem como de seus ângulos articulares no plano frontal, é essencial para o diagnóstico, classificação, quantificação do grau de desvio, e para o delineamento do tratamento cirúrgico corretivo. O presente estudo teve como objetivo mensurar e correlacionar os ângulos articulares do fêmur e da tíbia com o diferentes graus de luxação de patela. Foram obtidos exames radiográficos independentes do fêmur e da tíbia, nas projeções craniocaudal e caudocranial, respectivamente, de cães com e sem luxação de patela. As imagens radiográficas foram processadas digitalmente produzindo 92 exames radiográficos do membro pélvico em extensão total que foram divididos em grupos controle e luxação de patela. O grupo luxação foi subdividido de acordo com o tipo de luxação, medial ou lateral. Foram determinados os ângulos articulares, alinhamento e o eixo mecânico do membro pélvico correlacionando os resultados com a luxação de patela. Concluiu-se que o grau de luxação de patela interferiu na magnitude do desvio do eixo mecânico e no valor do ângulo mecânico femorotibial, e que o valor do ângulo mecânico lateral distal do fêmur foi maior nos cães com luxação de patela, sugerindo a presença de deformidade femoral distal. / The misalignment of the pelvic limb dogs contributes to abnormal bone development and medial or lateral displacement of the extensor mechanism. Increased incidences of the patellar dislocation in medium and large dogs stimulated alignment study and the associated bone deformities. Thus, knowledge of the mechanical axis and the pelvic limb alignment, as well as their joint angles in the frontal plane is essential for the diagnosis, classification, quantification of the degree of deviation and for the design of corrective surgery. The purpose of this study was to measure the femoral and tibial articular angles and and assess the relationship between it and the different degrees of patellar luxation. Independent radiographs of the femur and tibia of dogs with or without patellar luxation were obtained in the craniocaudal and caudocranial projections, respectively. The radiographic images were digitally processed producing 92 x-ray exams of the pelvic limb in full extension that were divided into control and patella luxation groups. The patellar luxation group was divided according to the type of dislocation, medial or lateral, and dislocation grade. The joint angles, alignment and the mechanical axis of the pelvic limb were determined and the results were correlated with the disease. In conclusion, the degree of patellar dislocation interfered with the magnitude of the mechanical axis deviation and the value of mechanical femorotibial angle, the value of the mechanical lateral distal femoral angle was higher in dogs with patellar dislocation, suggesting the presence of femoral distal deformity.

Este trabalho objetivou avaliar através do exame clínico, radiográfico e ultra-sonográfico a articulação fêmuro-tíbio-patelar pós desmotomia patelar medial. Foram utilizados oito equinos, machos e fêmeas, de peso, raça e idade variáveis. Todos animais foram submetidos a desmotomia patelar medial no membro pélvico direito. Os exames clínico e ultra-sonográfico foram realizados no 7º, 14º, 21º, 28º, 43º, 58º, 88º e 118º dia do pós-operatório. Os exames radiográficos e do líquido sinovial foram realizados no 15º, 30º, 60º, 90º e 120º dia do pós-operatório. No pós-operatório foi observado durante exame radiográfico do joelho direito, aumento do ângulo entre a superfície articular proximal da patela e a superfície cranial distal do fêmur, formação óssea na crista tibial, entesofitos na patela, deslocamento da patela e irregularidade óssea na superfície patelar lateral. No exame ultra-sonográfico foi observado aumento da espessura (p<0,05) no segmento proximal e médio do ligamento patelar intermédio do membro pélvico direito, desmite do patelar intermédio, enteseofitos na patela, distensão do recesso articular medial do fêmur, efusão articular e irregularidade da cartilagem do sulco troclear femoral. Conclui-se que a desmotomia patelar medial causa alterações no joelho devido a instbilidade articular e deve ser indicada apenas nos casos que não responderam a outras forma de tratamento. / This study aimed the evaluation of the femurotibiopatellar joint trough clinical, radiographic and ultrasonographic examinations after experimental medial patellar desmotomy. Medial patellar desmotomy was performed on the right hindlimb in eight mixed-breed horses. The clinical and ultrasonographic evaluation was performed on day 7, 14, 21, 28, 43, 58, 88 e 118 after surgery. The radiographic and synovial fluid evaluation was performed on day 15, 30, 60, 90 e 120 after surgery. It was observed during radiographic evaluation of the right stifle, an increase of the angle between the patellar proximal articular surface and the cranial distal femur surface. During ultrasonographic evaluation it was observed thickening (p<0,05) on the proximal and midlle segment of the midlle patellar ligament on the right hindlimb, entesophyte at the patella, femoral medial joint recess distending, joint effusion and cartilage irregularity of the femoral troclear groove. The medial patellar desmotomy causes stifle changes and must be performed only in animals non responsive to other treatment.

Chronic patellar tendinopathy is a degenerative tendon disorder characterized by chronic activity-related, anterior knee pain associated with localized tenderness, swelling and impaired performance, which is a common clinical problem in athletes. The pathogenesis of patellar tendinopathy is still largely unknown, although tendon overuse is the most commonly suggested etiological factor, and treatment is usually symptomatic. / Histopathologically, the predominant feature of patellar tendinopathy is tendinosis, which is characterized by progressive tissue degeneration with a failed healing response and the absence of inflammatory cells. Hypercellularity with non-tenocyte phenotype cells and tissue metaplasia, including hyaline metaplasia, fibrocartilaginous metaplasia and bony metaplasia were observed in clinical patellar tendinopathy samples. The degeneration of patellar tendon in patellar tendinopathy is an active cell-mediated process rather than a passive degenerative process. Using a patellar tendinopathy animal model, we observed the presence of chondrocytic and osteoblastic phenotype / markers in patellar tendinopathy samples with or without ossification, which was consistent with the findings in clinical samples. Interestingly, chondrocyte makers were expressed by healing tendon cells at week 2 which became round prior to their expression in the chondrocyte-like cells at week 4. This leads us to speculate that erroneous differentiation of tendon-derived stem cells (TDSCs) identified recently in tendon tissues by our group, to chondrocyte / osteoblasts, due to alteration of mechanical and biological microenvironment during overuse, may lead to the ectopic chondro-ossification and failed healing in patellar tendinopathy. Osteo-chondrogenic BMPs, such as BMP-2, BMP-4 and BMP-7 might be possible factors regulating the osteo-chondrogenic differentiation of TDSCs in the pathogenesis of patellar tendinopathy. / In conclusion, our results have provided new insights about the pathological mechanisms of patellar tendinopathy involving the resident stem cells, osteo-chondrogenic BMPs and mechanical overloading. Erroneous differentiation of TDSCs to chondrocytes / osteoblasts due to ectopic osteo-chondrogenic BMP-2 expression, which were induced by repetitive tensile loading stimulation, might account for the chondro-ossification and failed healing in patellar tendinopathy. Re-directing of stem cells for tenogenic differentiation by blocking the ectopic expression of osteo-chondrogenic BMPs may help to promote tendon healing in patellar tendinoapthy. / In this study, we hypothesized that (1) TDSCs isolated from pathological patellar tendon of the CI model will exhibit higher osteogenic and chondrogenic differentiation potential but lower proliferative capacity compared to TDSCs isolated from healthy patellar tendon. Rat pathological tendon in our collagenase-induced failed healing animal model will harbor more TDSCs compared to healthy patellar tendon. (2) Osteo-chondrogenic BMPs, such as BMP-2, BMP-4, and BMP-7, will be expressed ectopically in both preclinical and clinical samples of patellar tendinopathy. (3) BMP-2 will promote osteo-chondrogenic differentiation and inhibit tenogenic differentiation of TDSCs in vitro. (4) Repetitive tensile loading will increase the expression of BMP-2 in TDSCs in vitro. / Our results showed that TDSCs isolated from the collagenase-induced tendinopathic patellar tendon of the animal model exhibited higher osteogenic/chondrogenic differentiation potential as well as lower proliferative capacity, supporting that there might be some defects in the TDSCs from the animal model, which might undergo osteo-chondrogenic differentiation and hence reduced the pool of TDSCs for tendon repair in the development of patellar tendinopathy. The higher clonogenicity and increased yield of TDSCs in tendinopathic patellar tendon might be caused by a compensation for the impaired differentiation potential and proliferative capacity of TDSCs. The histopathological features of our clinical patellar tendinopathy were characterized by tissue degeneration. Non-tenocyte phenotype cells and tissue metaplasia, such as chondrocyte-like cells and endochondral ossification were also observed. We observed the ectopic expression of osteo-chondrogenic BMP-2, BMP-4 and BMP-7 in both our animal model and clinical samples of patellar tendinopathy, which might trigger the erroneous differentiation of TDSCs to non-tenocytes. Indeed, we further showed that BMP-2 could promote the osteo-chondrogenic and inhibit tenogenic differentiation of TDSCs in vitro, which might provide a possible explanation for ectopic chondro-ossification and failed healing in patellar tendinopathy. In addition, our results also showed that in vitro repetitive cyclic tensile loading could increase the expression of BMP-2 in TDSCs, which might provide a possible explanation for the ectopic expression of BMP-2 in patellar tendinopathy. / This study aimed to compare the osteogenic / chondrogenic differentiation potential, proliferative capacity and yield of TDSCs isolated from rat healthy patellar tendon and pathological tendon in our collagenase-induced failed tendon healing animal model of patellar tendinopathy in vitro. The histopathological characteristics of our clinical patellar tendinopathy with or without ossification were examined. The ectopic expression of BMP-2, BMP-4, and BMP-7 in both human and rat samples of patellar tendinopathy was also examined. The effects of BMP-2 on the osteogenic, chondrogenic and tenogenic differentiation of TDSCs was further investigated in vitro. The effect of repetitive tensile loading on the expression of BMP-2 in TDSCs was studied in vitro. / Rui, Yunfeng. / Advisers: Kai Ming Chan; Po Yee Lui. / Source: Dissertation Abstracts International, Volume: 73-06, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 172-193). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Submitted by PPG Medicina e Ci?ncias da Sa?de (medicina-pg@pucrs.br) on 2018-12-11T13:36:24Z No. of bitstreams: 1 EDUARDO_ANDRE_GOMES_KRIEGER.pdf: 1936090 bytes, checksum: 664d0dac12a0d4a16e41a647af134e1f (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-12-13T16:56:42Z (GMT) No. of bitstreams: 1 EDUARDO_ANDRE_GOMES_KRIEGER.pdf: 1936090 bytes, checksum: 664d0dac12a0d4a16e41a647af134e1f (MD5) / Made available in DSpace on 2018-12-13T17:07:12Z (GMT). No. of bitstreams: 1 EDUARDO_ANDRE_GOMES_KRIEGER.pdf: 1936090 bytes, checksum: 664d0dac12a0d4a16e41a647af134e1f (MD5) Previous issue date: 2018-08-10 / Introduction: Patellar chondropathy has an insidious onset, affecting patients with progressive, diffuse pain on the anterior aspect of the knee joint, and is one of the earliest signs of patellofemoral joint degenerative disease. Its etiology is still ill?defined, although risk factors such as female gender, increased body weight, and older age have been wellstablished in literature. There has been a prevalence of 40?60% under patellar cartilage macroscopic examination. The gold standard method for diagnosis is the arthroscopy; nonetheless, being a surgical procedure with high complication rates, its use is limited. With the advent of newer imaging methods, these modalities have been much more employed than diagnostic arthroscopy. Both conventional radiographs and CT scans provide indirect information on the condition of joint cartilage, whilst MRI provides more accurate data. There are no studies, however, highlighting the prevalence of patellar chondropathy in more recent imaging techniques such as the 3.0 Tesla MRI. Objective: To establish the prevalence of patellar chondropathy in 3.0 Tesla MRIs performed at Instituto do C?rebro da PUCRS between October 2016 and September 2017. Method: Data were collected by 3.0 Tesla MRIs of patients' knees obtained at Instituto do C?rebro da Pontif?cia Universidade Cat?lica do Rio Grande do Sul between September 2016 and August 2017, comprising a period of 12 months. Those MRIs were assessed by an experienced musculoskeletal radiologist, who confirmed the presence of patellar chondropathy and, when present, rated the finding into the four grades ascribed by the International Cartilage Repair Society. Results: A number of 291 patients were assessed during the period with 389 MRI scans. Of those patients, 308 (79.2%) were diagnosed with patellar chondropathy, whilst 81 (20.8%) were not. Chondropathy was more prevalent in the female gender, in subjects above 40 years of age, and in obese patients. When the results were weighed in ICRS classification, the milder grades (1 and 2) were seen in younger man (<30 years of age), while the more severe grades (3 and 4) were present in females, those above 40 years of age, and in obese patients. / Introdu??o: A condropatia patelar ? uma patologia de car?ter insidioso e que cursa com dor difusa na regi?o anterior do joelho, com caracter?stica progressiva, e ? um dos primeiros sinais de doen?a degenerativa na articula??o femoropatelar. A etiologia da doen?a ainda n?o est? bem definida, por?m os fatores de risco, como sexo feminino, alto peso corporal e indiv?duos mais velhos, est?o bem estabelecidos na literatura. Em estudos realizados atrav?s da macroscopia da cartilagem da patela, foi vista a preval?ncia entre 40?60%. O m?todo padr?o ouro para o diagn?stico ? a artroscopia, entretanto, por ser um procedimento cir?rgico, com elevados ?ndices de complica??o, seu uso ? restrito. Com o advento dos exames de imagem, estes passaram a ser mais utilizados do que a artroscopia diagn?stica. As radiografias convencionais e a tomografia computadorizada d?o informa??es indiretas sobre o estado das cartilagens articulares, j? a resson?ncia magn?tica pode prover mais dados. Todavia, n?o h? estudos que mostrem a preval?ncia da patologia em m?todos radiol?gicos mais recentes, como a resson?ncia magn?tica de 3.0 Tesla. Objetivo: Verificar a preval?ncia de condropatia patelar nos pacientes submetidos ao exame de resson?ncia magn?tica do joelho de alt?ssimo campo magn?tico (3.0 Tesla), realizada no Instituto do C?rebro da PUCRS no per?odo de outubro de 2016 a setembro de 2017. M?todo: Foram analisados os exames de resson?ncia magn?tica de joelho realizados no Instituto do C?rebro da Pontif?cia Universidade Cat?lica do Rio Grande do Sul em campo magn?tico de 3.0T, no per?odo de setembro de 2016 at? agosto de 2017, totalizando 12 meses. Estes foram analisados por radiologista com experi?ncia em interpreta??o de exames musculoesquel?ticos, que verificou a presen?a de condropatia patelar e, quando presente, classificou entre os quatro graus, de acordo com a classifica??o preconizada pela International Cartilage Repair Society. Resultados: Foram avaliados 291 pacientes durante o per?odo, com a realiza??o de 389 exames de resson?ncia nuclear magn?tica. Destes, 308 (79,2%) apresentavam condropatia patelar e apenas 81 (20,8%) n?o apresentavam. A patologia foi vista mais frequentemente nas mulheres, em indiv?duos acima de 40 anos e obesos. Quando classificada por graus, os mais leves (1 e 2) foram mais observados em homens e jovens (<30 anos) e os mais severos (3 e 4), no sexo feminino, acima de 40 anos e obesos.

Orientador: Bruno Watanabe Minto / Resumo: O presente estudo objetiva estabelecer padrões elastográficos normais das principais estruturas da articulação femorotibiopatelar (joelho) de cães saudáveis, em diferentes faixas etárias. Foram examinados 30 cães (60 articulações) da raça Beagle sem alterações musculoesqueléticas, os quais foram distribuídos em três grupos: jovens, adultos e idosos. Realizou-se elastografia ARFI do ligamento patelar, menisco medial, ligamento cruzado caudal e ligamento cruzado cranial de cada articulação. Análises qualitativas e quantitativas detectaram correlação positiva da velocidade de cisalhamento, ou seja, da rigidez das estruturas, com a idade dos cães. O ligamento patelar apresentou aumento gradual de sua rigidez em relação à idade; já o menisco e os ligamentos cruzados mostraram-se mais rígidos nos filhotes do que nos adultos, mas também revelaram suas maiores rigidezes nos animais idosos. Avaliou-se também a diferença de elasticidade das estruturas de acordo com o gênero e a condição reprodutiva dos animais. As fêmeas apresentaram todas as estruturas mais rígidas que os machos, com velocidades de cisalhamento diferindo entre 0,30 e 0,36 m/s dentre os dois gêneros; e apenas o menisco medial não se mostrou mais rígido nos animais castrados em relação aos inteiros, sendo a diferença daquele de apenas 0,02 m/s e a dos ligamentos de 0,40 a 0,47 m/s entre os grupos. Já quanto ao peso, não houve significância estatística em relação à elasticidade das estruturas. Tais achados corroboram os ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of this study is to establish normal elastographic patterns of the main knee structures of healthy dogs in different age groups. Thirty Beagles (60 joints) without musculoskeletal diseases were divided into three groups: young, adult and elderly. We performed ARFI elastography of the patellar ligament, medial meniscus, caudal cruciate ligament and cranial cruciate ligament. Qualitative and quantitative analyzes were performed, detecting a positive correlation of the shear velocity (rigidity of the structures) and the age of the dogs (p = 0.012). The patellar ligament showed a gradual increase in its rigidity in relation to age; the meniscus and the cruciate ligaments were more rigid in the pups than in adults, but also showed greater rigidity in elderly animals. The difference in elasticity of structures according to sex and reproductive condition was also evaluated. The females had all the structures more rigid than the males, with shear velocities differing between 0.30 and 0.36 m / s between the two groups. Only the medial meniscus did not appear to be more rigid in castrated animals. There was no statistical significance regarding the elasticity of the structures, according to weight. ARFI elastography is feasible technique in canine knees, not only as a method for the early diagnosis of ligament and meniscal alterations, but also to evaluate repercussion of instability in the contralateral limb and the impact of surgical and physiotherapeutic treatments. It is be... (Complete abstract click electronic access below) / Mestre