Background: The damaged articular cartilage has limited potential for repair. The treatment of osteochondral lesions in load bearing areas of the knee, are a therapeutic challenge. There are different cartilage repair techniques available. The main objective of these is achieving restoration of the congruity of the articular surface. Objectives : The objective was to compare clinical outcomes, assessed with the score of ICRS (International Cartilage Repair Society) with magnetic resonance images (MRI) of osteochondral autografts. Methods: Over a period of 4 years were performed 35 transplants of autologous osteochondral plugs (mosaico-plasty) in patients with lesions of the articular cartilage of the knee Outerbridge grade IV, smaller an 2.5 cm in diameter. The average patient age was 30.5 years. The average follow-up was 36 months. In 12 patients was conducted jointly ACL reconstruction. In a patient with a meniscal suture, 13 patients with partial lateral meniscectomy, and 15 partial medial meniscectomy. We designed a classification into three groups A, B and C taking into account 5 items that were valued in the postoperative MRI: degree of defect fill, restoration of the radius of curvature, angle of the curvature, a percentage of the implanted cartilage thickness over the surrounding, peripheral integration of subchondral bone. Results: We obtained good to excellent results in 87.5% of patients. Not finding a significant clinical-radiological correlation in the postoperative evaluation with MRI. Conclusions: MRI allows us to analyze a series of data after an osteochondral transfer that are useful for monitoring the process of incorporation of the graft and cartilage regeneration of the articular surface. Small variations in the orientation of the osteochondral graft, or slight irregularities at the level of the chondral surface of the graft does not appear to correlate with adverse clinical outcomes in the short term. MR imaging of knee cartilage sequence, among other studies, would be needed for more accurate evaluation. We conclude that mosaico-plasty is a safe and effective for treatment of grade IV osteochondral lesions, small in young patients with good results in the medium term. Although it would take longterm monitoring to observe that these cases are not progressing with time of knee osteoarthritis.

Introducción: El cartílago articular dañado tiene un potencial limitado de reparación. El tratamiento de las lesiones osteocondrales en las zonas de carga de la rodilla representa un desafío. Existen diferentes técnicas de reparación del cartílago cuyo principal objetivo es restaurar la congruencia de la superficie articular. En este trabajo se compararon los resultados clínicos, valorados con el puntaje de la International Cartilage Repair Society con las imágenes de resonancia magnética de los autoinjertos osteocondrales. Materiales y métodos: En un período de 4 años se realizaron 35 trasplantes de tacos osteocondrales autólogos (mosaicoplastia) en pacientes con lesiones del cartílago articular de la rodilla de grado IV de Outerbridge, de hasta 2,5 cm de diámetro. La media de edad de los pacientes fue de 30,5 años. El seguimiento promedio fue de 36 meses. En 12 casos se realizó, en forma conjunta, la reconstrucción del LCA; en un paciente se efectuó una sutura meniscal; en 13 pacientes, una meniscectomía parcial lateral; y en 15 pacientes, una meniscectomía parcial medial. Se diseñó una clasificación en tres grupos (A, B y C) teniendo en cuenta cinco ítems que fueron valorados en la resonancia magnética posoperatoria: grado del relleno del defecto, restauración del radio de curvatura, inclinación del taco, porcentaje del grosor del cartílago implantado con respecto al circundante e integración periférica del hueso subcondral. Resultados: Se obtuvieron resultados buenos a excelentes en el 87,5% de los pacientes. No se encontró una correlación clínico-radiológica significativa en la evaluación con la resonancia magnética posoperatoria. Conclusiones: La resonancia magnética permite analizar una serie de datos, después de una transferencia osteocondral, que son útiles para controlar el proceso de incorporación del injerto y regeneración del cartílago en la superficie articular. Las pequeñas variaciones en la orientación del taco injertado o las leves irregularidades en la superficie condral del injerto no parecen correlacionarse con resultados clínicos adversos a corto plazo. La resonancia magnética de rodilla con secuencia para cartílago, entre otros estudios, es necesaria para una evaluación más precisa. Se concluyó que la mosaicoplastia es una técnica segura y eficaz para el tratamiento de las lesiones osteocondrales de grado IV, pequeñas, en pacientes jóvenes, con buenos resultados a mediano plazo. Es necesario el seguimiento a largo plazo para observar que estos casos no progresen con el tiempo a la artrosis de rodilla.

Since little information is available on the epizootiological status of Trypanosoma evansi in South America and particularly Brazil, we evaluated equine serum samples collected in 1993, 1994, 1995 and 1997 for the presence of antibodies against this trypanosome species. Our study shows corroborative evidence about the correlation among high T. evansi seroprevalence and the rainy season in the Pantanal, Brazil. The higher seroprevalence was 79.2% in horses from a ranch located in the Nhecolândia sub-region in 1994 and the lower 5.8% in animals from the same ranch in 1997. No seroprevalence was found in 1993. The possible re-introduction of T. evansi in the region as well as the relationship among our results with the outbreaks reported in 1994, are briefly discussed.

The financial impact of the first outbreak of Trypanosoma vivax in the Brazilian Pantanal wetland is estimated. Results are extended to include outbreaks in the Bolivian lowlands providing a notion of the potential influence of the disease and an analytical basis. More than 11 million head of cattle, valued at more than US$3 billion are found in the Brazilian Pantanal and Bolivian lowlands. The total estimated cost of the 1995 outbreak of T. vivax is the sum of the present values of mortality, abortion, and productivity losses and treatment costs, or about 4% of total brood cow value on affected ranches. Had the outbreak gone untreated, the estimated losses would have exceeded 17% of total brood cow value.