Impresión 3D en Cirugía Ortopédica y Traumatología. Revisión sistemática de su aplicabilidad y estudio de los métodos de esterilización más adecuados para la utilización en quirófanos de las impresiones realizadas en el hospital.

Introduction In-Hospital 3D printing has been broadly developed since the end of the addictive manufacturing patents. However, although there are many printing technologies, the most frequent in our field are Fused Deposition Modelling (FDM) and Stereolithography (SLA), which usually use hollow infill patterns in order to save time and material. It is common to use these models and surgical guides in the operating room, however, there were no publications warranting an adequate sterilization of the in-house prints. Objectives To describe systematically all the current applications of in-hospital 3D printing up to date and to run an experimental study which demonstrates the sterilization of the inside of our anatomical models and surgical guides. Material and Methods A systematic review was made on PubMed to obtain all the published articles regarding this topic up to December 2021. Those publications in other language (not in English or Spanish) or describing industrial applications, cell therapies, pharma therapies or involving human specimens were rejected. A record card was made for each application to make further search easier. For the experimental study, a total of 24 cylinders were designed and printed with a 3D printer in Polylactic Acid (PLA) with an infill density of 12%. Manufacturing was paused when 60% of the print was reached and 20 of the cylinders were inoculated with 0.4 mL of a suspension of S epidermidis ATTCC 1228 in saline solution at turbidity 1 McFarland. Printing was resumed, being all the pieces completely sealed with the inoculum inside. Posteriorly, 4 groups were made according to the chosen sterilization method: Ethylene Oxide (EtO), Gas Plasma, Steam Heat or non-sterilized (positive control). Each group included 5 contaminated cylinders and 1 non-contaminated cylinder as a negative control. After sterilization, the inside of the cylinders was cultured during 7 days. Results We obtained a total of 1193 articles in the research, of which 298 articles met the inclusion criteria, finding a total of 143 applications which are summarized as record cards. In the sterility study, we observed bacterial growth of just a few Forming Colony Units (FCU) in 4 out of 5 positive controls and in 2 out of 5 contaminated cylinders sterilized with Gas Plasma. We could not assess any bacterial growth in any of the EtO or Steam Heat samples or in any of the negative controls. Pieces sterilized under Steam Heat resulted completely deformed. Conclusions There are multiple applications for in-house 3D printing in the field of orthopaedics. High temperatures reached during the procedure of additive manufacturing can decrease the bacterial load of the biomodels. However, there is a potential risk of contamination during the proce- dure. We recommend sterilization with EtO for in-hospital 3D-printed PLA hollow biomodels or guides. Otherwise, in case of using Gas Plasma, an infill of 100% should be applied.Introducción La impresión 3D hospitalaria ha cobrado un gran impulso desde la liberalización de las patentes sobre la fabricación aditiva. Aunque existen multitud de tecnologías de impresión, las más frecuentes en nuestro medio son la impresión por deposición de material fundido (FDM) y la impresión estereolitográfica (SLA), las cuales, suelen recurrir a patrones de relleno incompletos para ahorrar tiempo y material. Aunque es frecuente la utilización de biomodelos y guías quirúrgicas obtenidas por este medio en los quirófanos, no existían hasta la fecha estudios que garantizasen una adecuada esterilidad de los mismos. Objetivos Realizar una descripción sistematizada de todas las aplicaciones descritas de la impresión 3D hospitalaria hasta la fecha y hacer un estudio experimental que demuestre la capacidad esterilizante del interior de nuestros biomodelos y guías quirúrgicas. Material y Métodos Se realiza una revisión sistemática en PubMed para obtener todos los artículos publicados sobre el tema hasta diciembre de 2021, descartándose aquellos en otro idioma o que tratan sobre aplicaciones industriales, celulares, farmacológicas o experimentales en cadáver. Se realiza una ficha de cada una de las aplicaciones para facilitar su posterior consulta. Por otro lado, realizamos un estudio experimental con 24 cilindros impresos en ácido poliláctico con una densidad de relleno del 12%. La fabricación se detuvo cuando se alcanzó el 60% de la impresión y 20 de los cilindros se inocularon con 0.4mL de una suspensión de S epidermidis ATTCC 1228 en solución salina con una turbidez de 1 McFarland. Tras la inoculación, se continuó la impresión quedando las piezas completamente selladas con el inóculo en su interior. Posteriormente, se crearon 4 grupos de acuerdo con el método de esterilización empleado (Óxido de etileno, Gas plasma, Autoclave y grupo control positivo, sin esterilizar). Cada grupo incluyó 5 cilindros contaminados y 1 no contaminado como control negativo. Tras la esterilización, el interior de los cilindros se cultivó durante 7 días. Resultados Se han obtenido un total de 1193 artículos en la búsqueda de los cuales 298 artículos cumplieron los criterios de inclusión, obteniéndose un total de 143 aplicaciones que se exponen a modo de fichas. En el estudio de esterilidad se observe crecimiento bacteriano de unas pocas unidades formadoras de colonias en 4 de los 5 controles positivos y en 2 de los 5 cilindros contaminados y esterilizados con Gas plasma. No se observó crecimiento en ninguno de los cilindros esteriliados con Óxido de etileno o Autoclave, ni tampoco en ninguno de los controles negativos. Sin embargo, aquellas muestras esterilizadas en Autoclave se encontraron completamente deformadas. Conclusiones Existen infinidad de aplicaciones de la impresión 3D hospitalaria en el campo de la cirugía ortopédica y traumatología. Las altas temperaturas alcanzadas durante el proceso de fabricación aditiva pueden disminuir la carga bacteriana de los biomodelos. Sin embargo, existe un riesgo potencial de contaminación durante el procedimiento, por lo que recomendamos la esterilización con Óxido de etileno para las impresiones intrahospitalarias de biomodelos y guías huecas realizadas con ácido poliláctico. En caso de utilizar Gas plasma, recomendamos un relleno del 100% o la utilización de otros materiales más resistentes a las altas temperaturas del Autoclave.Escuela de DoctoradoDoctorado en Investigación en Ciencias de la Salu

Meniscopatía aguda en paciente joven. Tratamiento conservador a propósito de un caso.

Meniscal tears are injuries that appear each time in younger patients, usually males and athletes, due to the increase in the performance of physical activity and the intensity of it.They are also very limiting lesions in terms of activity, so, the patient usually demands an early clinical resolution to reincorporate their activity.In this article we highlight the importance of the meniscus as a force distribution and articular cartilage protection structure in a long term.For that reason, we emphasize the importance of all those treatments aimed at meniscal conservation, and a meditation is raised around meniscal injuries in patients in which sport is their main activity and for which an early reincorporation to the activity is essential.In contrast we find amateur athlete patients where, if the injury allows, we can opt for a conservative treatment for some months with restriction of sports activity at the expense of long-term preservation of the largest possible meniscal surface.Las lesiones meniscales son una patología que aparecen cada vez en pacientes más jóvenes, generalmente varones y deportistas, debido al incremento en la realización de actividad física y a la intensidad de la misma. Así mismo son lesiones muy limitantes en cuanto a la actividad, por lo que el paciente generalmente demanda una resolución clínica temprana para reincorporarse a su actividad. En este artículo ponemos de manifiesto la importancia que tiene el menisco como estructura para distribución de fuerzas y por consiguiente protección del cartílago articular a largo plazo. Por ello recalcamos la importancia de todos aquellos tratamientos encaminados a la conservación meniscal, y se plantea una reflexión en torno a las lesiones meniscales en pacientes en los que el deporte es su principal actividad y para los cuales es imprescindible una reincorporación temprana a la actividad. En contraposición encontramos a los pacientes deportistas amateur donde, si la lesión lo permite, podemos optar por un tratamiento conservador durante más meses con restricción de la actividad deportiva a expensas de conservar a largo plazo la mayor superficie meniscal posible

Clinical applications of “in-hospital” 3D printing in hip surgery: a systematic narrative review

Producción CientíficaIntroduction: Interest in 3D printing for orthopedic surgery has been increasing since its progressive adoption in most of the hospitals around the world. The aim of the study is to describe all the current applications of 3D printing in patients undergoing hip surgery of any type at the present time. Materials and Methods: We conducted a systematic narrative review of publications indexed in MedLine through the search engine PubMed, with the following parameters: 3D printing AND (orthopedics OR traumatology) NOT tissue engineering NOT scaffold NOT in vitro and deadline 31 July 2023. After reading the abstracts of the articles, papers were selected according to the following criteria: full text in English or Spanish and content related to hip surgery. Those publications involving experimental studies (in vitro or with anatomical specimens) or 3D printing outside of hospital facilities as well as 3D-printed commercial implants were excluded. Results are presented as a reference guide classified by disease, including the used software and the steps required for the development of the idea. Results: We found a total of 27 indications for in-house 3D printing for hip surgery, which are described in the article. Conclusions: There are many surgical applications of 3D printing in hip surgery, most of them based on CT images. Most of the publications lack evidence, and further randomized studies should be encouraged to assess the advantages of these indications

Comparative study of layer-by-layer deposition techniques for poly(sodium phosphate) and poly (allylamine hydrochloride)

UPNa. Departamento de Ingeniería Eléctrica y Electrónica. Laboratorio de Dispositivos Ópticos NanoestructuradosAn inorganic short chain polymer, poly(sodium phosphate), PSP, together with poly(allylamine hydrochloride), PAH, is used to fabricate layer-by-layer (LbL) films. The thickness, roughness, contact angle, and optical transmittance of these films are studied depending on three parameters: the precursor solution concentrations (10−3 and 10−4 M), the number of bilayers deposited (20, 40, 60, 80, and 100 bilayers), and the specific technique used for the LbL fabrication (dipping or spraying). In most cases of this experimental study, the roughness of the nanofilms increases with the number of bilayers. This contradicts the basic observations made in standard LbL assemblies where the roughness decreases for thicker coatings. In fact, a wide range of thickness and roughness was achieved by means of adjusting the three parameters mentioned above. For instance, a roughness of 1.23 or 205 nm root mean square was measured for 100 bilayer coatings. Contact angles close to 0 were observed. Moreover, high optical transmittance is also reported, above 90%, for 80 bilayer films fabricated with the 10−4 M solutions. Therefore, these multilayer structures can be used to obtain transparent superhydrophilic surfaces.This work was supported by the Spanish Economy and Competitiveness Ministry-FEDER TEC2010-17805

Volatile organic compound optical fiber sensors: a review

Volatile organic compound (VOC) detection is a topic of growing interest with applications in diverse fields, ranging from environmental uses to the food or chemical industries. Optical fiber VOC sensors offering new and interesting properties which overcame some of the inconveniences found on traditional gas sensors appeared over two decades ago. Thanks to its minimum invasive nature and the advantages that optical fiber offers such as light weight, passive nature, low attenuation and the possibility of multiplexing, among others, these sensors are a real alternative to electronic ones in electrically noisy environments where electronic sensors cannot operate correctly. In the present work, a classification of these devices has been made according to the sensing mechanism and taking also into account the sensing materials or the different methods of fabrication. In addition, some solutions already implemented for the detection of VOCs using optical fiber sensors will be described with detail.This work was supported by Spanish Ministerio de Ciencia y Tecnología and FEDER Research Grants CICYT-TIC 2003-000909 and CICYT-TEC 2004-05936-C02-01/MIC

Luminescence-based optical sensors fabricated by means of the layer-by-layer nano-assembly technique

Luminescence-based sensing applications range from agriculture to biology, including medicine and environmental care, which indicates the importance of this technique as a detection tool. Luminescent optical sensors are required to be highly stable, sensitive, and selective, three crucial features that can be achieved by fabricating them by means of the layer-by-layer nano-assembly technique. This method permits us to tailor the sensors0 properties at the nanometer scale, avoiding luminophore aggregation and, hence, self-quenching, promoting the diffusion of the target analytes, and building a barrier against the undesired molecules. These characteristics give rise to the fabrication of custom-made sensors for each particular application.This work was supported by the Spanish State Research Agency (AEI) through the TEC2016- 79367-C2-2-R project and the European Regional Development Fund (ERDF-FEDER). Nerea de Acha would also like to acknowledge her pre-doctoral fellowship (reference BES-2014-069692) funded by the Spanish Ministry of Economy and Competitiveness through the TEC2013-43679-R project

Detection of ethanol in human breath using optical fiber long period grating coated with metal-organic frameworks

Trabajo presentado en la Eurosensors 2017 Conference. París, 3–6 de septiembre de 2017.An optical fiber sensor for ethanol detection in exhaled breath has been developed. It has been fabricated by functionalizing a Long Period Grating with a metal-organic framework, ZIF-8. The sensor’s response was tested by exposure to exhaled breath of a person before and after the ingestion of alcoholic drinks, showing a higher wavelength difference between the resonance bands in the second case. Further work will analyze cross-sensitivity towards temperature, relative humidity and carbon dioxide.The authors would like to acknowledge Spanish Ministry of Economy and Competitiveness for the financial support through TEC2016-78047-R project