Extremity high-grade sarcomas in elderly patients, are they candidates for surgery? Experience in a sarcoma referral center.

The number of elderly patients diagnosed with cancer is increasing. However, knowledge regarding cancer in elderly patients is very scarce. The aim of this study is to analyze the differences in management and outcomes of high-grade extremity sarcomas between elderly and middle-aged patients. Two cohorts were made (> 70 and 30/50 years old) among patients treated in a multidisciplinary unit of a national reference center between 2011 and 2017 with a minimum of 2 years of follow-up. The management and outcomes between these two cohorts were compared. Seventy patients were included, 34 young patients and 36 elderly patients. The only difference between the treatment schemes was the chemotherapy used, 67.6% of the young patients received chemotherapy versus 16.7% of the elderly patients (p = 0.000015). There were no differences either in the overall survival or the progression-free survival between groups at 1 and 2-year follow-up. Deceases for other causes were nearly exclusive of elderly patients at a median of 45.57 months. Surgery is the treatment of choice for sarcomas in both elderly and young patients having similar results in terms of progression-free survival, overall survival, and surgery outcomes. The use of chemotherapy is the only difference in the treatment schemes between both groups. In the elderly patient with minimal or no comorbidity and good functional reserve, surgical curative treatment should be chosen. As for frail elderly patients, the therapeutic objectives must be focused mainly on quality of life and palliation of symptoms.

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.

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".

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

BACKGROUND: 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. METHODS: Observational, descriptive, retrospective, and monocentric study of 907 instances of 3D printing from November 2015 to March 2020. Variables such as product type, utility, time, or manufacturing materials were analyzed. RESULTS: Orthopedic Surgery and Traumatology, Oral and Maxillofacial Surgery, and Gynecology and Obstetrics are the medical specialties that have manufactured the largest number of processes. Working and printing time, as well as the amount of printing material, is different for different types of products and input data. The most common printing material was polylactic acid, although biocompatible resin was introduced to produce surgical guides. In addition, the hospital has worked on the co-design of custom-made implants with manufacturing companies and has also participated in tissue bio-printing projects. CONCLUSIONS: The integration of 3D printing in a university hospital allows identifying the conceptual evolution to "point-of-care manufacturing."

Application of 3D printing and distributed manufacturing during the first-wave of COVID-19 pandemic. Our experience at a third-level university hospital.

BACKGROUND: 3D printing and distributed manufacturing represent a paradigm shift in the health system that is becoming critical during the COVID-19 pandemic. University hospitals are also taking on the role of manufacturers of custom-made solutions thanks to 3D printing technology. CASE PRESENTATION: We present a monocentric observational case study regarding the distributed manufacturing of three groups of products during the period of the COVID-19 pandemic from 14 March to 10 May 2020: personal protective equipment, ventilatory support, and diagnostic and consumable products. Networking during this period has enabled the delivery of a total of 17,276 units of products manufactured using 3D printing technology. The most manufactured product was the face shields and ear savers, while the one that achieved the greatest clinical impact was the mechanical ventilation adapters and swabs. The products were manufactured by individuals in 57.3% of the cases, and our hospital acted as the main delivery node in a hub with 10 other hospitals. The main advantage of this production model is the fast response to stock needs, being able to adapt almost in real time. CONCLUSIONS: The role of 3D printing in the hospital environment allows the reconciliation of in-house and distributed manufacturing with traditional production, providing custom-made adaptation of the specifications, as well as maximum efficiency in the working and availability of resources, which is of special importance at critical times for health systems such as the current COVID-19 pandemic.

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.

Patient-specific desktop 3D-printed guides for pelvic tumour resection surgery: a precision study on cadavers.

PURPOSE: 3D-printed patient-specific instruments have become a useful tool to improve accuracy in pelvic tumour resections. However, their correct placement can be challenging in some regions due to the morphology of the bone, so it is essential to be aware of the possible placement errors in each region. In this study, we characterize these errors in common pelvic osteotomies. METHODS: We conducted an experiment with 9 cadaveric specimens, for which we acquired a pre-operative computed tomography scan. Small PSIs were designed for each case following a realistic surgical approach for four regions of the pelvis: iliac crest (C), supra-acetabular (S), ischial (I), and pubic (P). Final surgical placement was based on a post-operative scan. The resulting positions were compared with pre-operative planning, obtaining translations, rotations, and maximum osteotomy deviations in a local reference frame defined based on the bone's morphology. RESULTS: Mean translations and rotations in the direction of the osteotomy plane were as follows: C = 5.3 mm, 6.7°; S = 1.8 mm, 5.1°; I = 1.5 mm, 3.4°; P = 1.8 mm, 3.5°. Mean translations in the remaining axes were below 2 mm. Maximum osteotomy deviations (75% of cases) were below 11.8 mm in C (7.8 mm for half-length), 7.8 mm in S (5.5 mm for half-length), 5.5 mm in I, and 3.7 mm in P. CONCLUSION: We have characterized placement errors for small PSIs in four regions of the pelvis. Our results show high errors in C and S PSIs in the direction of the resection plane's normal, and thus large osteotomy deviations. Deviations in short osteotomies in S, I and P and placement errors in the remaining directions were low. The PSIs used in this study are biocompatible and can be produced with a desktop 3D printer, thus minimizing manufacturing cost.

Intraoperative radiotherapy for extremity soft-tissue sarcomas: can long-term local control be achieved?

BACKGROUND: Intraoperative electron-beam radiation therapy (IOERT) during limb-sparing surgery has the advantage of delivering a single high boost dose to sarcoma residues and surgical bed area near to radiosensitive structures with limited toxicity. Retrospective studies have suggested that IOERT may improve local control compared to standard radiotherapy and we aimed to demonstrate this theory. Therefore, we performed an observational prospective study to determine (1) if it is possible to achieve high local control by adding IOERT to external-beam radiation therapy (EBRT) in extremity soft-tissue sarcomas (STS), (2) if it is possible to improve long-term survival rates, and (3) if toxicity could be reduced with IOERT MATERIALS AND METHODS: From 1995-2003, 39 patients with extremity STS were treated with IOERT and postoperative radiotherapy. The median follow-up time was 13.2 years (0.7-19). Complications, locoregional control and survival rates were collected. RESULTS: Actuarial local control was attained in 32 of 39 patients (82%). Control was achieved in 88% of patients with primary disease and in 50% of those with recurrent tumors (p = 0.01). Local control was shown in 93% of patients with negative margins and in 50% of those with positive margins (p = 0.002). Limb-sparing was achieved in 32 patients (82%). The overall survival rate was 64%. 13% of patients had grade ≥3 acute toxicity, and 12% developed grade ≥3 chronic toxicity. CONCLUSION: IOERT used as a boost to EBRT provides high local control and limb-sparing rates in patients with STS of the extremities, with less toxicity than EBRT alone.