ABSTRACT
Introducción: Una de las promesas de la era informática se suscita desde la investigación in silico (investigación asistida por computadora). En el presente trabajo nos propusimos crear un modelo 3D in silico de un caso clínico real, imprimirlo en 3D y navegar una osteotomía previamente planeada. Materiales y métodos: Se presenta el caso de un paciente de 11 años con diagnóstico de osteosarcoma localizado en la metáfisis proximal de la tibia izquierda. Se practicó la planificación tridimensional a partir del procesamiento de las imágenes correspondientes a la tomografía y la resonancia magnética. La resección y la reconstrucción se practicaron siguiendo el modelo virtual creado. Resultados: La planificación tridimensional pudo ser creada. Fue posible reproducir un modelo 3D en un escenario virtual identificando hueso sano, tumor y márgenes oncológicos planificando y ejecutando una osteotomía biplanar. Conclusiones: Es posible que la aplicación de estas técnicas en la práctica de la ortopedia general permita planificaciones virtuales preoperatorias en múltiples situaciones. De esta forma, contribuiría a disminuir la incidencia de fallas intraoperatorias imprevistas, contribuyendo a obtener procedimientos quirúrgicos predecibles, implementando así una nueva manera de realizar desarrollo, investigación y entrenamiento en ortopedia y traumatología mediante el uso de tecnología in silico.
Background: One of the major challenge for orthopedic surgery is to create a preoperative plan in a 3D virtual space and reproduce it in a 3D model. Thanks to rapid prototyping (RP) models, we can build a three-dimensional scaled bone model with a tumor inside. Our objective was to obtain segmented images from a tibial bone, with a tumor. Next, determine safe margins inside, in order to create a preoperative 3D plan. Then, print a RP model, with colors inside, and reproduce the surgery (simulation) with a navigation system. The feasibility of such procedure is based on our hypothesis, that it is possible to simulate an in vitro scenario for bonetumor surgery, and apply complex osteotomies with navigation, thus preserving healthy tissue. Methods: An 11-year old patient with knee pain, andproximal tibia osteosarcoma diagnosed by biopsy, was scanned with CT Multislice. The preoperative planning was applied using a 3D simulation platform. Two planes were created into the bone, one near the tumor, in red (3mm of unsafe margin), the other, far from the tumor, in blue (3mm of safe margin). Our RP model was created using Z-printer Spectrum Z-510 and ZP131 powder in 1hour and 47 minutes. Weprinted the model in two halves, in order to print the inner colored structures, which were then attached with glue,thus obtaining the final RP bone model.The preoperative plan was masked and exported from our 3D virtual platform to the navigator. The osteotomies were applied with Stryker Navigation System II, using the planned 3D virtual path. After performing the osteotomy, the piece was separated with a saw into the two original halves. Results: The separated RP bone was used as an anatomic pathological simulated model. We could see the correct and wrong paths of the previously planned osteotomy in the 3D virtual scenario, applied with navigation...