Validación de los modelos de impresión 3D paciente específicos para cirugía ortopédica oncológica pélvica mediante estudio en cadáver

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Medicina, leída el 13-07-2022Los tumores del anillo pélvico suponen un reto por la dificultad de obtener márgenes quirúrgicos adecuados. Herramientas como la navegación quirúrgica o la impresión 3D parala fabricación de plantillas de posicionamiento quirúrgico paciente-específicas ayudan en la planificación preoperatoria y la ejecución intraoperatoria. Su correcta colocación es fundamental en localizaciones complejas como la pelvis, por lo que es necesario identificar los errores de posicionamiento y la precisión de dichas herramientas paciente-específicas. Objetivos. La hipótesis principal de este estudio es que las plantillas de corte paciente específicas(PCPE) obtenidas mediante impresión 3D son una herramienta fiable para la realización de osteotomías en el abordaje oncológico de tumoraciones óseas localizadas en el anillo pélvico. Como objetivos se pretende demostrar la precisión de las PCPE adaptadas a las vías de abordaje y objetivar la influencia de la superficie anatómica sobre la que se asientan, así como comprobar que la navegación sobre PCPE es una opción válida para guiar las osteotomíaspélvicas, y que puede constituir un método de validación del posicionamiento intraoperatorio de las mismas...Pelvic ring tumours are challenging because of the difficulty in obtaining adequate surgical margins. Tools such as surgical navigation or 3D printing for the fabrication of patient-specific surgical positioning templates help in preoperative planning and intraoperative execution. Their correct positioning is essential in complex locations such as the pelvis, so it is necessary to identify positioning errors and the accuracy of these patients pecifictools. Hypothesis and objectives. The main hypothesis of this study is that patient-specific cutting templates (PCPE) obtained by 3D printing are a reliable tool for performing osteotomies in the oncological approach to bone tumours located in the pelvic ring. The objectives are to demonstrate the accuracy of PCPE adapted to the approach routes and to objectify the influence of the anatomical surface on which they are placed, as well as to prove that navigation on PCPE is avalid option for guiding pelvic osteotomies, and that it can constitute a validation method for intraoperative positioning of these osteotomies...Fac. de MedicinaTRUEunpu

Desktop 3D Printing: Key for Surgical Navigation in Acral Tumors?

Surgical navigation techniques have shown potential benefits in orthopedic oncologic surgery. However, the translation of these results to acral tumor resection surgeries is challenging due to the large number of joints with complex movements of the affected areas (located in distal extremities). This study proposes a surgical workflow that combines an intraoperative open-source navigation software, based on a multi-camera tracking, with desktop three-dimensional (3D) printing for accurate navigation of these tumors. Desktop 3D printing was used to fabricate patient-specific 3D printed molds to ensure that the distal extremity is in the same position both in preoperative images and during image-guided surgery (IGS). The feasibility of the proposed workflow was evaluated in two clinical cases (soft-tissue sarcomas in hand and foot). The validation involved deformation analysis of the 3D-printed mold after sterilization, accuracy of the system in patient-specific 3D-printed phantoms, and feasibility of the workflow during the surgical intervention. The sterilization process did not lead to significant deformations of the mold (mean error below 0.20 mm). The overall accuracy of the system was 1.88 mm evaluated on the phantoms. IGS guidance was feasible during both surgeries, allowing surgeons to verify enough margin during tumor resection. The results obtained have demonstrated the viability of combining open-source navigation and desktop 3D printing for acral tumor surgeries. The suggested framework can be easily personalized to any patient and could be adapted to other surgical scenarios.This work was supported by projects TEC2013-48251-C2-1-R (Ministerio de Economía y Competitividad); PI18/01625 and PI15/02121 (Ministerio de Ciencia, Innovación y Universidades, Instituto de Salud Carlos III and European Regional Development Fund “Una manera de hacer Europa”) and IND2018/TIC-9753 (Comunidad de Madrid).Publicad

Combining Surgical Navigation and 3D Printing for Less Invasive Pelvic Tumor Resections

Surgical interventions for musculoskeletal tumor resection are particularly challenging in the pelvic region due to their anatomical complexity and proximity to vital structures. Several techniques, such as surgical navigation or patient-specific instruments (PSIs), have been introduced to ensure accurate resection margins. However, their inclusion usually modifies the surgical approach making it more invasive. In this study, we propose to combine both techniques to reduce this invasiveness while improving the precision of the intervention. PSIs are used for image-to-patient registration and the installation of the navigation’s reference frame. We tested and validated the proposed setup in a realistic surgical scenario with six cadavers (12 hemipelvis). The data collected during the experiment allowed us to study different resection scenarios, identifying the patient-specific instrument configurations that optimize navigation accuracy. The mean values obtained for maximum osteotomy deviation or MOD (maximum distance between the planned and actual osteotomy for each simulated scenario) were as follows: for ilium resections, 5.9 mm in the iliac crest and 1.65 mm in the supra-acetabular region, and for acetabulum resections, 3.44 mm, 1.88 mm, and 1.97 mm in the supra-acetabular, ischial and pubic regions, respectively. Additionally, those cases with image-to-patient registration error below 2 mm ensured MODs of 2 mm or lower. Our results show how combining several PSIs leads to low navigation errors and high precision while providing a less invasive surgical approach.This work was supported by the Ministerio de Ciencia e Innovación, Instituto de Salud Carlos III, and European Regional Development Fund ‘‘Una manera de hacer Europa,’’ under Project PI18/01625.Publicad

Conceptual evolution of 3D printing in orthopedic surgery and traumatology: from "do it yourself" to "point of care manufacturing"

Background: 3D printing technology in hospitals facilitates production models such as point-of-care manufacturing. Orthopedic Surgery and Traumatology is the specialty that can most benefit from the advantages of these tools. The purpose of this study is to present the results of the integration of 3D printing technology in a Department of Orthopedic Surgery and Traumatology and to identify the productive model of the point-of-care manufacturing as a paradigm of personalized medicine. Methods: Observational, descriptive, retrospective and monocentric study of a total of 623 additive manufacturing processes carried out in a Department of Orthopedic Surgery and Traumatology from November 2015 to March 2020. Variables such as product type, utility, time or materials for manufacture were analyzed. Results: The areas of expertise that have performed more processes are Traumatology, Reconstructive and Orthopedic Oncology. Pre-operative planning is their primary use. Working and 3D printing hours, as well as the amount of 3D printing material used, vary according to the type of product or material delivered to perform the process. The most commonly used 3D printing material for manufacturing is polylactic acid, although biocompatible resin has been used to produce surgical guides. In addition, the hospital has worked on the co-design of customized implants with manufacturing companies. Conclusions: The integration of 3D printing in a Department of Orthopedic Surgery and Traumatology allows identifying the conceptual evolution from “Do-It-Yourself” to “POC manufacturing”.Analysis and interpretation of the data supported by Project PI18/01625 (Ministerio de Ciencia, Innovación y Universidades, Instituto de Salud Carlos III) and European Regional Development Fund ("Una manera de hacer Europa")

Combining Augmented Reality and 3D Printing to Improve Surgical Workflows in Orthopedic Oncology: Smartphone Application and Clinical Evaluation

During the last decade, orthopedic oncology has experienced the benefits of computerized medical imaging to reduce human dependency, improving accuracy and clinical outcomes. However, traditional surgical navigation systems do not always adapt properly to this kind of interventions. Augmented reality (AR) and three-dimensional (3D) printing are technologies lately introduced in the surgical environment with promising results. Here we present an innovative solution combining 3D printing and AR in orthopedic oncological surgery. A new surgical workflow is proposed, including 3D printed models and a novel AR-based smartphone application (app). This app can display the patient’s anatomy and the tumor’s location. A 3D-printed reference marker, designed to fit in a unique position of the affected bone tissue, enables automatic registration. The system has been evaluated in terms of visualization accuracy and usability during the whole surgical workflow. Experiments on six realistic phantoms provided a visualization error below 3 mm. The AR system was tested in two clinical cases during surgical planning, patient communication, and surgical intervention. These results and the positive feedback obtained from surgeons and patients suggest that the combination of AR and 3D printing can improve efficacy, accuracy, and patients’ experience.This work was supported by projects PI18/01625 (Ministerio de Ciencia, Innovación y Universidades, Instituto de Salud Carlos III and European Regional Development Fund “Una manera de hacer Europa”) and IND2018/TIC-9753 (Comunidad de Madrid)

HoloLens 1 vs. HoloLens 2: Improvements in the New Model for Orthopedic Oncological Interventions

This work analyzed the use of Microsoft HoloLens 2 in orthopedic oncological surgeries and compares it to its predecessor (Microsoft HoloLens 1). Specifically, we developed two equivalent applications, one for each device, and evaluated the augmented reality (AR) projection accuracy in an experimental scenario using phantoms based on two patients. We achieved automatic registration between virtual and real worlds using patient-specific surgical guides on each phantom. They contained a small adaptor for a 3D-printed AR marker, the characteristic patterns of which were easily recognized using both Microsoft HoloLens devices. The newest model improved the AR projection accuracy by almost 25%, and both of them yielded an RMSE below 3 mm. After ascertaining the enhancement of the second model in this aspect, we went a step further with Microsoft HoloLens 2 and tested it during the surgical intervention of one of the patients. During this experience, we collected the surgeons’ feedback in terms of comfortability, usability, and ergonomics. Our goal was to estimate whether the improved technical features of the newest model facilitate its implementation in actual surgical scenarios. All of the results point to Microsoft HoloLens 2 being better in all the aspects affecting surgical interventions and support its use in future experiences.This work was supported by projects PI18/01625, AC20/00102-3 and Era Permed PerPlanRT (Ministerio de Ciencia, Innovación y Universidades, Instituto de Salud Carlos III, Asociación Española Contra el Cáncer and European Regional Development Fund "Una manera de hacer Europa") and IND2018/TIC-9753 (Comunidad de Madrid)

Point-of-care manufacturing: a single university hospital's initial experience

The integration of 3D printing technology in hospitals is evolving toward production models such as point-of-care manufacturing. This study aims to present the results of the integration of 3D printing technology in a manufacturing university hospital.Analysis and interpretation of the data supported by Project PI18/01625 (Ministerio de Ciencia, Innovación y Universidades, Instituto de Salud Carlos III) and European Regional Development Fund (“Una manera de hacer Europa”)

Post-radiation pelvic sarcomas after radiotherapy treatment of prostate adenocarcinoma

Background: The number of publications reporting the appearance of post-radiation secondary tumors has increased in parallel with the development of radiotherapy. However, little information is available about the presence of sarcomas associated with prostate radiotherapy. Objective: To review cases of pelvic sarcoma associated with prostate radiotherapy in a tertiary hospital. Methods: Following the criteria established by Cahan, 11 pelvic sarcoma patients with a history of radiotherapy treatment of prostatic adenocarcinoma between the years 2006 to 2016 were identified. A descriptive study was designed to review the characteristics of patients, tumors, therapy administered, and its effect on the outcome of the cancer. Results: The average age of patients upon diagnosis was 72.27 years (60-79), with an average latency time of 6.27 years (4-9 years) between radiotherapy and diagnosis of sarcoma. The mean radiotherapy dose was 74Gy (70-78). The most common location of the sarcoma was regions II-III of the pelvic girdle (72%), followed by the pelvic cavity. The main histological type was undifferentiated pleomorphic sarcoma (54%); two patients presented metastases at the time of diagnosis. In total, 81.8% of patients were treated surgically with curative intent, and of these, seven received adjuvant chemotherapy. Mean follow-up was 14 months, with a two-year survival rate of 18.2%. Conclusion: Given the poor prognosis of post-radiation pelvic sarcomas, efforts must be made to establish protocols for early diagnosis and to develop aggressive, standardized treatment guidelines. [Arch Clin Exp Surg 2018; 7(3.000): 94-99

Giant-cell tumor of the patella: An uncommon cause of fracture

Primary patellar tumors are highly unusual. Most are benign neoplasms with giant-cell tumors being the most common, followed by chondroblastomas and aneurysmal bone cysts. Intralesional curettage and bone grafting is the treatment of choice for most giant-cell tumors in the patella. The use of adjuvants can reduce the high recurrence rate. This is a case report of a giant-cell tumor in a 61-year-old man who was diagnosed with a pathological fracture in the patella after minimal trauma. Extended curettage through an osteotomy made in the medial cortical of the patella was performed. The tumor cavity was filled with high viscosity bone cement and the medial cortical was repositioned. Histological analysis showed mononuclear cells and numerous multinucleated giant cells, confirming the diagnosis. Twenty-four months after surgery, the patient was asymptomatic and there was no evidence of local recurrence. Epidemiology, symptomatology, imagenology, histopathology, treatment options and prognoses of giant-cell tumors of the patella are discussed herein. [Arch Clin Exp Surg 2017; 6(2.000): 112-116