Three-Dimensional Printing and Navigation in Bone Tumor Resection

One of the most promising advances raised by the current computer age is performing research “in silico,” which means computer-assisted. The objective of this chapter is firstly to evaluate if a 3D in-silico model of an oncological patient could be used to make a 3D-printed prototype in real scale, discriminating precisely healthy tissues, tumoral tissues and oncological margins. Secondly, the objective is to evaluate if this prototype could be representative enough to allow testing osteotomies under navigated guidance based on images. A tumor resection for a patient with diagnosed metaphyseal osteosarcoma of the proximal tibia was transferred into a rapid prototyping model, fabricated using 3D printing and representing different structures in different colors. The planned osteotomy was executed using Stryker Navigator to guide the cutting saw and the prototype was opened to verify the precision of the performed osteotomy. Both osteotomy planes showed successful correspondence with the safe margin, with a maximum error of 1 mm. The application of these techniques in general orthopedics would help to reduce the incidence of unforeseen intraoperative failures, contributing to obtain predictable surgical procedures. This would implement a new way of performing development, research and training in orthopedics and traumatology by in-silico technology

Ewing sarcoma of the bone. Multidisciplinary approach and oncological results in 88 patients

El sarcoma de Ewing óseo es un tumor poco frecuente, agresivo, que afecta principalmente a niñosy adultos jóvenes. Existe ausencia de registros en nuestro país respecto de la prevalencia de estaenfermedad, los esquemas de tratamiento utilizados y sus resultados. El objetivo fue analizar, en un grupode pacientes con sarcoma de Ewing óseo tratados con quimioterapia y cirugía de conservación de miembro,las tasas de supervivencia global, de recurrencia local y los factores de riesgo oncológicos. Se incluyó a 88pacientes. La edad media de la serie fue de 14.5 años y el seguimiento promedio de 8.8 años. La tasa de supervivencia global fue de 79.5% a los 2 años, de 69% a 5 años y de 64% a 10 años. Los factores pronósticosnegativos asociados a menor supervivencia fueron: mala respuesta a la quimioterapia, edad ≥ de 16 años,localización central, y recurrencia local. En el análisis multivariable únicamente la respuesta a la quimioterapiatuvo significancia estadística. La tasa libre de recurrencia local a 2 y 5 años fue del 87%. La mala respuesta ala quimioterapia fue el único factor significativo para la recurrencia local. Consideramos que la cirugía de conservación de miembro asociada a quimioterapia pre y postoperatoria debe ser el tratamiento para el sarcomade Ewing óseo, alcanzando de esta manera una supervivencia global a 5 años del 69%. En nuestra serie, larespuesta a la quimioterapia ha sido el factor pronóstico más relevante para supervivencia y recurrencia local.Ewing sarcoma of the bone is a rare, highly aggressive tumor that typically affects children and young adults. In Argentina, the lack of Ewing’s sarcoma registries reflects in the absence of information regarding prevalence, treatment protocols and patient´s outcome. The purpose of this study was to analyze, in a group of patients diagnosed with Ewing sarcoma of the bone, treated with chemotherapy and limb-conserving surgery, their overall survival rate, local recurrence rate, and oncological risk factors. A retrospective research was conducted between 1990 and 2017. Eighty-eight patients with Ewing sarcoma of the bone matched the inclusion criteria. Median age was 14.5 years and median follow-up was 8.8 years. Overall survival rate was 79.5%, 69% and 64% at 2, 5 and 10 years respectively. Negative prognostic factors, associated with less survival rate after univariate analysis, were: bad response to chemotherapy (tumoral necrosis 0-89%), age > 16 years-old, central tumor localization and local recurrence. Gender and tumor size were not significant prognostic factors. After multivariate analysis, response to chemotherapy remained statistical significant. Local recurrence-free survival rate at 2 and 5 years was 87%. Tumor response to chemotherapy (0-89%) was the only significant factor for local recurrence. We consider that limb-salvage surgery, with neoadjuvant and adjuvant chemotherapy, are the mainstays of treatment for Ewing’s sarcoma, with an overall survival rate, at 5 years, of 69%. In this population, response to chemotherapy is the most relevant prognostic factor, being associated with both local recurrence and overall survival.Fil: Sanchez Saba, Javier E.. Instituto Universidad Escuela de Medicina del Hospital Italiano; ArgentinaFil: Abrego, Mariano O.. Instituto Universidad Escuela de Medicina del Hospital Italiano; ArgentinaFil: Albergo, José I.. Instituto Universidad Escuela de Medicina del Hospital Italiano; ArgentinaFil: Farfalli, Germán Luis. Instituto Universidad Escuela de Medicina del Hospital Italiano; ArgentinaFil: Aponte Tinao, Luis A.. Instituto Universidad Escuela de Medicina del Hospital Italiano; ArgentinaFil: Ayerza, Miguel A.. Instituto Universidad Escuela de Medicina del Hospital Italiano; ArgentinaFil: Cayol, Federico. Instituto Universidad Escuela de Medicina del Hospital Italiano; ArgentinaFil: Streitenberger, Patricia. Instituto Universidad Escuela de Medicina del Hospital Italiano; ArgentinaFil: Risk, Marcelo. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Medicina Traslacional E Ingenieria Biomedica. - Hospital Italiano. Instituto de Medicina Traslacional E Ingenieria Biomedica. - Instituto Universitario Hospital Italiano de Buenos Aires. Instituto de Medicina Traslacional E Ingenieria Biomedica.; ArgentinaFil: Roitman, Pablo Daniel. Instituto Universidad Escuela de Medicina del Hospital Italiano; Argentin

Clinical Study Allograft Reconstruction for the Treatment of Musculoskeletal Tumors of the Upper Extremity

In comparison with the lower extremity, there is relatively paucity literature reporting survival and clinical results of allograft reconstructions after excision of a bone tumor of the upper extremity. We analyze the survival of allograft reconstructions in the upper extremity and analyze the final functional score according to anatomical site and type of reconstruction. A consecutive series of 70 allograft reconstruction in the upper limb with a mean followup of 5 years was analyzed, 38 osteoarticular allografts, 24 allograft-prosthetic composites, and 8 intercalary allografts. Kaplan-Meier survival analysis of the allografts was performed, with implant revision for any cause and amputation used as the end points. The function evaluation was performed using MSTS functional score. Sixteen patients (23%) had revision surgery for 5 factures, 2 infections, 5 allograft resorptions, and 2 local recurrences. Allograft survival at five years was 79% and 69% at ten years. In the group of patients treated with an osteoarticular allograft the articular surface survival was 90% at five years and 54% at ten years. The limb salvage rate was 98% at five and 10 years. We conclude that articular deterioration and fracture were the most frequent mode of failure in proximal humeral osteoarticular reconstructions and allograft resorption in elbow reconstructions. The best functional score was observed in the intercalary humeral allograft

Allograft Reconstruction for the Treatment of Musculoskeletal Tumors of the Upper Extremity

In comparison with the lower extremity, there is relatively paucity literature reporting survival and clinical results of allograft reconstructions after excision of a bone tumor of the upper extremity. We analyze the survival of allograft reconstructions in the upper extremity and analyze the final functional score according to anatomical site and type of reconstruction. A consecutive series of 70 allograft reconstruction in the upper limb with a mean followup of 5 years was analyzed, 38 osteoarticular allografts, 24 allograft-prosthetic composites, and 8 intercalary allografts. Kaplan-Meier survival analysis of the allografts was performed, with implant revision for any cause and amputation used as the end points. The function evaluation was performed using MSTS functional score. Sixteen patients (23%) had revision surgery for 5 factures, 2 infections, 5 allograft resorptions, and 2 local recurrences. Allograft survival at five years was 79% and 69% at ten years. In the group of patients treated with an osteoarticular allograft the articular surface survival was 90% at five years and 54% at ten years. The limb salvage rate was 98% at five and 10 years. We conclude that articular deterioration and fracture were the most frequent mode of failure in proximal humeral osteoarticular reconstructions and allograft resorption in elbow reconstructions. The best functional score was observed in the intercalary humeral allograft

Massive Bone Loss from Fungal Infection after Anterior Cruciate Ligament Arthroscopic Reconstruction

Although there are numerous reports of septic pyogenic arthritis after arthroscopic anterior cruciate ligament (ACL) reconstruction, there is limited information regarding the outcomes of fungal infection. We determined the outcomes of six patients with mycotic infection after regular ACL reconstruction. There were four males and two females with a mean age of 33 years. We determined the number of procedures performed, bone loss originating to control infection, and final reconstruction in these patients. An average of five arthroscopic lavage procedures had been performed at the referring centers. Fungal infection was diagnosed based on pathologic samples; five infections were the result of mucormycosis and one was Candida. After final débridement, the mean segmental bone loss was 12.8 cm. All patients were treated with intravenous antifungal coverage and cement spacers before final reconstruction. At final followup, all patients were free of clinical infection. Three had reconstruction with an allograft-prosthesis composite, two with hemicylindrical allografts, and one with an intercalary allograft arthrodesis. Despite the extremely unusual presentation of this complication, surgeons should be aware of potential and catastrophic consequences of this severe complication after ACL reconstruction

Proximal Femur Allograft-prosthesis with Compression Plates and a Short Stem

Proximal femur allograft-prosthesis composites (APCs) performed with compression plates and a short stem theoretically could minimize the resorption or nonunion that reportedly occurs with long stems bypassing the diaphyseal osteotomy. To confirm this theoretical consideration, we retrospectively reviewed 34 patients with 38 proximal femoral APCs using a short-cemented femoral stem and compression plates for diaphyseal osteotomy fixation. In 26 patients, the plate fixation extended over at least half the femoral stem and in 12, it did not. We reinserted the abductor mechanism with two techniques: in 10 cases the host trochanter was reattached to the APC, and in 28 the host tendons were sutured to the tendinous insertion of the allograft. The overall survival of the entire series was 72% at 5 years and 69% at 10 years. Eleven of the 38 (29%) APCs were removed: three for infection, one for local recurrence of tumor, and seven for fractures. Trendelenburg gait occurred in four of 21 patients with direct tendon-to-tendon suture of the abductor mechanism and in three of six patients with trochanteric osteotomy. The overall APC survival rate was greater in patients in whom the allograft was adequately protected with internal fixation than in patients in whom it was not