The Effect of the Overexpression or Addition of IGF1 and FGF2 in Human Chondrocytes Included in a Fibrin Matrix and Cultivated in a Dynamic Environment.

Hyaline cartilage is a highly specialized tissue. When injured, its repair capacity is low, which results in the massive destruction of the articular surface. Using tissue engineering and genetic engineering techniques, it is possible to provide a suitable microenvironment providing chondrocyte growth factors involved in the development of hyaline cartilage proteins, as well as cell proliferation and differentiation. Our aim was to stimulate the synthesis of an extracellular matrix via the chondrocytes included in a fibrin matrix through the addition or overexpression of IGF1 and/or FGF2, while maintaining a constant agitation of the culture medium. Collagen type II and glycosaminoglycans increased during the entire incubation time. In contrast, collagen type I decreased its expression under the same culture conditions, transfecting or supplementing growth factors to chondrocytes. However, chondrocytes that were not transfected or supplemented showed a general increase in the proteins analyzed in this study. The presence of IGF1 and FGF2 increased the protein synthesis of the hyaline cartilage, regardless of which one was the source of growth factors. Continuous agitation using the spinner flask allows for the adequate nutrition of chondrocytes included in the fibrin matrix. However, they require growth factors to up-regulate or down-regulate collagenous proteins.

Treatment of Chondral Knee Lesions with Autologous Chondrocytes Embedded in a Fibrin Scaffold. Clinical and Functional Assessment / Tratamento de lesões condrais no joelho com condrócitos autólogos embebidos em arcabouço de fibrina. Avaliação clínica e funcional

Abstract Objective The aim of our study is to analyze the clinical and functional results obtained using autologous chondrocytes embedded in a fibrin scaffold in knee joint injuries. Methods We included 56 patients, 36 men and 20 women, with a mean age 36 years. Six of the patients were professional athletes, with single knee injuries that were either chondral or osteochondral (43 chondral, 9 osteochondral, 2 cases of osteochondritis dissecans and 2 osteochondral fractures), 2 to 10 cm2 in size and ≤ 10 mm deep, with no signs of osteoarthritis. The location of the injury was in the patella (8), the medial femoral condyle (40) and lateral femoral condyle (7) and one in the trochlea. The mean follow-up was 3 (range: 1-6) years. The clinical course was assessed using the Cincinnati and Knee Injury and Osteoarthritis Outcome (KOOS) scores, 6 and 12 months after surgery. The paired Student t-test was used to compare pre-and postoperative results. Results Six months after the implant, patients resumed their everyday activities. On the assessment scores, their condition was improving in comparison with their presurgical state (p < 0.05). They were also able to carry out their sporting activities more easily than prior to surgery (p < 0.05). Conclusion The seeding of chondrocytes in fibrin may provide a favorable microenvironment for the synthesis of extracellular matrix and improved the clinical condition and activity of the patients 1 year after surgery.

Resumo Objetivo O objetivo do nosso estudo é analisar os resultados clínicos e funcionais do tratamento de lesões nas articulações do joelho com condrócitos autólogos embebidos em arcabouço de fibrina. Métodos O estudo foi realizado com 56 pacientes (36 homens e 20 mulheres) com idade média de 36 anos; 6 indivíduos eram atletas profissionais. Os pacientes apresentavam lesões únicas, condrais ou osteocondrais (43 condrais, nove osteocondrais, 2 casos de osteocondrite dissecante e duas fraturas osteocondrais) no joelho, com 2 a 10 cm2 de tamanho e ≤ 10 mm de profundidade, sem sinais de osteoartrite. As lesões estavam localizadas na patela (8), no côndilo femoral medial (40), no côndilo femoral lateral (7) e na tróclea (1). O período médio de acompanhamento foi de 3 anos (faixa de 1-6 anos). A evolução clínica foi avaliada pelos escores de Cincinnati e Knee Injury and Osteoarthritis Outcome (KOOS), 6 e 12 meses após a cirurgia. O teste t de Student pareado foi utilizado para comparação dos achados pré e pós-operatórios. Resultados Os pacientes retomaram suas atividades diárias 6 meses após o implante. Os escores avaliados demonstraram a melhora em comparação ao estado pré-cirúrgico (p < 0,05). Além disso, os pacientes conseguiram realizar suas atividades esportivas com mais facilidade do que antes da cirurgia (p < 0,05). Conclusão A cultura de condrócitos em fibrina pode proporcionar um microambiente favorável para a síntese de matriz extracelular e melhorar a condição clínica e a atividade dos pacientes 1 ano após a cirurgia

Osteogenesis induced by a three-dimensional bioimplant composed of demineralised bone matrix, collagen, hydroxyapatite, and bone marrow-derived cells in massive bone defects: An experimental study.

Treatment of massive bone defects is one of the most difficult problems to solve in orthopedics. At present, there is no consensus on the best way to resolve these problems. The aim of our study was to evaluate the effect of a three-dimensional bioimplant over massive bone defects, and to analyse if it improves the speed and quality of integration in recipient bone compared to allograft treatment. Fifteen female lambs with massive bone defects, surgically created in their tibias, were randomly divided into three groups of five lambs each: Group I -treated with the bioimplant; Group 2 -treated with the bioimplant plus nucleated cells of autologous bone marrow; Group 3 -treated with a frozen allograft. Radiographs were taken post-treatment at weeks 1, 6, and 12. Animals were euthanized to obtain the studied bone segment for morphological analyses. TREATMENT: with bioimplants vs. bioimplant plus bone marrow nucleated cells (BMNCs) showed a notorious osteogenic effect, but with greater osteoid synthesis and cellularity in the latter. These results suggest that combined treatment with bioimplants and BMNCs have an additive effect on massive bone defects in lambs. These experimental results could be applied to repair damaged human bone.

[Interosseous electrostimulation in a model of lengthening with external fixation]. / Electroestimulación interósea en un modelo de elongación con fijación externa.

BACKGROUND: A fracture repair involves complex cellular processes. However, despite optimal treatment, some fractures heal slowly or do not repair. These complications support the need for innovative therapies. Electromagnetic stimulation is a non-invasive technology that could have a direct impact on many cellular pathways. OBJECTIVE: To demonstrate the effectiveness of electro-stimulation by alternating current applied during bone elongation to accelerate the consolidation process for 30 days in an animal model. MATERIALS AND METHODS: A device with closed circuit and graduated voltage was designed and kept in contact with the external fixator. Group A was elongated without electro-stimulation and group B was electro-stimulated since the beginning of the distraction. Radiographs were taken at 15 and 30 days post-surgical. Haematoxylin and eosin staining and Masson's trichrome stain were performed. RESULTS: No significant difference were observed in bone density of group A (4.05±3.24, P=0.163). In group B there was a significant difference (61.06±20.17, P=0.03) in bone density. Group A maintained a fibrous tissue repair, with areas of cartilage and bone matrix. Group B had more organised tissue in the stages of bone repair. CONCLUSION: Because there is a significant difference in the growth and callus formation at 15 and 30 days between groups, electro-stimulation could be considered as an adjuvant during bone elongation.

Human bone morphogenetic protein 2-transduced mesenchymal stem cells improve bone regeneration in a model of mandible distraction surgery.

BACKGROUND: Bone morphogenetic proteins (BMPs) are actively involved in ossification, and BMP-2 participates throughout the entire process. Gene therapy for bone regeneration using adenovirus-expressing BMPs has been successful in small mammals, but it has not been satisfactory in large mammals. METHODS: We generated a 3-component implant (3C graft) comprising autologous mesenchymal stem cells (MSCs), ex vivo transduced with an adenovirus vector-expressing BMP-2 and embedded in a demineralized human bone matrix (DBM). RESULTS: In vitro studies demonstrated vector-induced osteogenesis; osteoblast population and mineralization of the extracellular matrix were greater in the vector-transduced cultures than in the controls (nontransduced MSCs stimulated with osteogenic media were used as positive controls, and nontransduced MSCs served as a negative control). The 3-component grafts were used to fill osteotomies created by bone distraction surgery in mongrel dogs. Control groups comprised dogs with bone distraction alone and dogs with nontransduced MSC grafts. The radiography follow-up, performed 10 weeks after distraction, demonstrated a remarkable reduction in the consolidation period compared with controls. Postmortem mandibles submitted for anatomic and histologic analyses showed improved remodeling and bone maturation in the 3C-grafted dogs. Inflammatory infiltrates were not observed in any of the treated areas, and no liver toxicity was detected. CONCLUSIONS: We demonstrated acceleration of osteogenesis in a dog model for bone distraction by using an implant of BMP-2 modified MSCs. These results are helpful for future clinical trials of mandible bone distraction.

Knee chondral lesions treated with autologous chondrocyte transplantation in a tridimensional matrix: clinical evaluation at 1-year follow-up.

BACKGROUND: Despite the many studies on chondral injury repair, no outcomes have been evaluated with the Western Ontario and McMaster (WOMAC) Universities osteoarthritis index, the Knee Injury and Osteoarthritis Outcome Score (KOOS), and the Oxford Knee Score, all of which are specific for evaluating the presence of osteoarthritis. MATERIALS AND METHODS: We evaluated the clinical progress of patients following autologous chondrocyte implantation (ACI) performed by our Bone and Tissue Bank using a technique in which cells, instead of being introduced to the articular defect in a liquid form, are implanted into a tridimensional matrix of semisolid collagen (Condrograft((R))). A total of 22 patients underwent the procedure, 15 of whom were available for a 1-year follow-up that included clinical evaluation by WOMAC score before and after surgery and KOOS and the Oxford Knee Score after surgery. RESULTS: The results were improved WOMAC score from 56.4 before surgery to 16.2 after surgery (P < 0.002), average KOOS score of 83.6, and average Oxford Knee Score of 18.8. CONCLUSIONS: These results indicate that our tridimensional matrix technique effectively improved patients' quality of life, at least in the short term, and delayed any subsequent procedure. Long-term assessment is necessary to determine the true value of this technique.

El uso del cemento en la artroplastía total de cadera / The use of cement in total hip arthroplasty

Desde el inicio del uso del metilmetacrilato como método de fijación en la Artroplastía Total de Cadera(ATC), se ha relacionado la aparición de líneas radiolúcidas (LR) periprotésicas y su progresión, con el diagnóstico de aflojamiento; en ocasiones en ausencia de sintomatología. El objetivo del presente estudio es la evaluación radiológica y correlación clínica de los pacientes en los cuales se realizó ATC y se utilizó metilmetacrilato como método de fijación, valorándose expedientes clínicos y radiológicos de 46 pacientes cuyos procedimientos fueron realizados de enero de 1986 a diciembre de 1995. Treinta y tres artroplastías fueron realizadas en 28 pacientes (16M: 12F) con una media de edad de 59.7 años, se evalúa el componente femoral y el acetabular comparando las radiografías mínimo de 3 años. Para valorar la estabilidad del componente acetabular se utilizaron las tres zonas descritas por Charnley, el nivel clínico de actividad fue evaluado de acuerdo a los criterios propuestos por Jhonston y cols. De los 33 componentes femorales, en las radiografías postquirúrgicas 30 presentaron LR, sólo 3 no la presentaron, de los 30 que sí la tuvieron, en 19 hubo progresión en la extensión de dicha línea, en 14 no progresó y en ninguno se presentó aflojamiento del componente femoral. De los 21 componentes acetabulares 20 presentaron LR en las radiografías postquirúrgicas, sólo una no la presentó, 7 componentes presentaron progresión en los controles radiográficos incluyendo la aparición de la LR en el componente que no la había presentado en las radiografías postquirúrgicas, 14 componentes no progresaron, 2 componentes presentaron aflojamiento aséptico, de estos 2, uno presentó LR en las radiografías postquirúrgicas y el otro no. En estos casos los pacientes fueron sometidos a una cirugía de revisión. Todos los pacientes evaluados clínicamente incluso los 2 que fueron sometidos a cirugía de revisión, no presentaron limitación para la marcha ni para realizar sus actividades cotidianas. Cuatro pacientes refirieron dolor leve en rodilla ipsilateral el cual se atenuaba con el reposo, 5 pacientes refirieron dolor no incapacitante en cadera contralateral que cedía al reposo...