Application of 3D Printing Technology in the Treatment of Hoffa's Fracture Nonunion / Aplicação da tecnologia de impressão 3D no tratamento da pseudartrose da fratura de Hoffa

Abstract Objective To evaluate a proposed three-dimensional (3D) printing process of a biomodel developed with the aid of fused deposition modeling (FDM) technology based on computed tomography (CT) scans of an individual with nonunion of a coronal femoral condyle fracture (Hoffa's fracture). Materials and Methods Thus, we used CT scans, which enable the evaluation of the 3D volumetric reconstruction of the anatomical model, as well as of the architecture and bone geometry of sites with complex anatomy, such as the joints. In addition, it enables the development of the virtual surgical planning (VSP) in a computer-aided design (CAD) software. This technology makes it possible to print full-scale anatomical models that can be used in surgical simulations for training and in the choice of the best placement of the implant according to the VSP. In the radiographic evaluation of the osteosynthesis of the Hoffa's fracture nonunion, we assessed the position of the implant in the 3D-printed anatomical model and in the patient's knee. Results The 3D-printed anatomical model showed geometric and morphological characteristics similar to those of the actual bone. The position of the implants in relation to the nonunion line and anatomical landmarks showed great accuracy in the comparison of the patient's knee with the 3D-printed anatomical model. Conclusion The use of the virtual anatomical model and the 3D-printed anatomical model with the additive manufacturing (AM) technology proved to be effective and useful in planning and performing the surgical treatment of Hoffa's fracture nonunion. Thus, it showed great accuracy in the reproducibility of the virtual surgical planning and the 3D-printed anatomical model.

Resumo Objetivo Avaliar uma proposta de processo de impressão tridimensional (3D) de um biomodelo preparado com o auxílio da tecnologia de modelagem por deposição de material fundido (fused deposition modeling, FDM, em inglês) a partir de imagens de tomografia computadorizada (TC) de um indivíduo com pseudartrose de fratura coronal do côndilo femoral (fratura de Hoffa). Materiais e Métodos Para tanto, utilizamos imagens de TC, que permitem estudar a reconstrução volumétrica 3D do modelo anatômico, além da arquitetura e geometria óssea de sítios de anatomia complexa, como as articulações. Também permite o planejamento cirúrgico virtual (PCV) em um programa de desenho assistido por computador (computer-aided design, CAD, em inglês). Essa tecnologia possibilita a impressão de modelos anatômicos em escala real que podem ser utilizados em simulações cirúrgicas para o treinamento e a escolha do melhor posicionamento do implante de acordo com o PCV. Na avaliação radiográfica da osteossíntese da pseudartrose de Hoffa, verificou-se a posição do implante no modelo anatômico impresso em 3D e no joelho do paciente. Resultados O modelo anatômico impresso em 3D apresentou características geométricas e morfológicas semelhantes às do osso real. O posicionamento dos implantes em relação à linha de pseudartrose e pontos anatômicos foram bastante precisos na comparação do joelho do paciente com o modelo anatômico impresso em 3D. Conclusão A utilização do modelo anatômico virtual e do modelo anatômico impresso em 3D com a tecnologia de manufatura aditiva (MA) foi eficaz e auxiliou o planejamento e a realização do tratamento cirúrgico da pseudartrose da fratura de Hoffa. Desta forma, foi bastante preciso na reprodutibilidade do planejamento cirúrgico tanto virtual quanto no modelo anatômico impresso em 3D.

5S and 5W2H Tools Applied to Research Laboratories: Experience from Instituto Carlos Chagas - FIOCRUZ/PR for Cell Culture Practices

Abstract Good cell culture practices are a set of technical and management tools recommended for application in research and service laboratories to guarantee the traceability and reproducibility of in vitro experiments. However, most research laboratories do not have a structured quality assurance system and have difficulties organizing their workflows or even priorities in implementing acceptable laboratory practices. In this study, we applied management and quality assurance tools to define the steps necessary to implement acceptable laboratory practices in the multiuser laboratory of cell culture and establish a cell bank at the Carlos Chagas Institute FIOCRUZ-PR. Our team applied the 5W2H and 5S tools for initial diagnosis and established an action plan to implement and manage the laboratory over two years. Thereby, we defined the scope of laboratory activities, including the demand for establishing a cell bank, the supply of cell lines to internal users, user training, and quality control tests. We also mapped the main activities, establishing their flows and all the necessary documentation to ensure traceability and reproducibility. Additionally, the laboratory was organized in compliance with the 5S principles. In conclusion, using management tools, such as the 5W2H and 5S methods, is a simple and affordable method to organize and manage a cell culture laboratory and can be applied to other research laboratories.

Absorbed doses in salivary and thyroid glands from panoramic radiography and cone beam computed tomography

Abstract Introduction: Panoramic radiography and cone beam computed tomography (CBCT) are very important in the diagnosis of oral diseases, however patients are exposed to the risk of ionizing radiation. This paper describes our study aimed at comparing absorbed doses in the salivary glands and thyroid due to panoramic radiography and CBCT and estimating radiation induced cancer risk associated with those methods. Methods Absorbed doses of two CBCT equipment (i-CAT® Next Generation and SCANORA® 3D) and a digital panoramic device (ORTHOPANTOMOGRAPH® OP200D) were measured using thermoluminescent dosimeters loaded in an anthropomorphic phantom on sublingual, submandibular, parotid and thyroid glands. Results Absorbed doses in the i-CAT® device ranged between 0.02 (+/-0.01) and 2.23 mGy (+/-0.03), in the SCANORA™ device ranged from 0.01 (+/-0.01) to 2.96 mGy (+/-0.29) and in the ORTHOPANTOMOGRAPH® OP200D ranged between 0.04 mGy and 0.78 mGy. The radiation induced cancer risk was highlighted in the salivary glands, which received higher doses. The protocols that offer the highest risk of cancer are the high resolution protocols of CBCT equipment. Conclusion CBCT exposes patients to higher levels of radiation than panoramic radiography, so the risks and benefits of each method should be considered. The doses in CBCT were dependent on equipment and exposure parameters, therefore adequate selection minimizes the radiation dose.

Continuous therapeutic ultrasound in the healing process in rat skin / Ultrassom terapêutico contínuo no processo de cicatrização em pele de ratos

Abstract Introduction : The therapeutic ultrasound is one of the main resources utilized on physical therapy to stimulate the healing due its thermal and mechanic effects. However, your application still not properly standardized. Objective :To analyze the presence of the collagens types I and III stimulated by the ultrasonic wave in continuous mode at the cutaneous injury local for first intention. Material and methods : It was utilized 90 Wistar rats, young adults, with average weight of 230g, divided in 3 groups of 30 animals: control group, treated with ultrasound off; group 1, treated with ultrasound 0.5 W/cm2 and group 2, treated with ultrasound 2.0 W/cm2. Each group was subdivided in 3 subgroups according with the healing phases, 3, 7 and 21 days of consecutive therapeutic sessions. The ultrasound therapy began 24 hours after the termination of the surgical act, at the dorsal region, applying frequency of 3 MHz and intensities 0.5 W/cm2 and 2.0 W/cm2 during 5 minutes under sliding technique. Later, the animals were sacrificed according to the healing phases for removal of incisional area and histological analyses. Conclusions : The results allowed conclude that the continuous mode of therapeutic ultrasound in the intensities 0.5 W/cm2 and 2.0 W/cm2promoted stimulus to formation of collagens types I and III in the lesion area for first intention.

Resumo Introdução : O ultrassom terapêutico é um dos principais recursos utilizados na fisioterapia para estimular a cicatrização devido aos seus efeitos térmicos e mecânicos. No entanto, sua aplicação ainda não está devidamente padronizada. Objetivo : Analisar a presença dos colágenos tipos I e III estimulados pela onda ultrassônica no modo contínuo no local da lesão cutânea por primeira intenção. Materiais e métodos : Foram utilizados 90 ratos Wistar, adulto-jovens, com peso médio de 230 g, divididos em 3 grupos de 30 animais: grupo controle, tratado com ultrassom desligado; grupo 1, tratado com ultrassom 0,5 W/cm² e grupo 2, tratado com ultrassom 2,0 W/cm². Cada grupo foi subdividido em 3 subgrupos de acordo com as fases de cicatrização 3, 7 e 21 dias de sessões terapêuticas consecutivas. A terapia ultrassônica teve início 24 horas após o término do ato cirúrgico, na região dorsal, aplicando frequência de 3 MHz e as intensidades 0,5 W/cm² e 2,0 W/cm² no tempo de 5 minutos sob a técnica de deslizamento. Posteriormente, os animais foram sacrificados de acordo com as fases de cicatrização para remoção da área incisional e análise histológica. Conclusão : Os resultados possibilitaram concluir que o modo contínuo do ultrassom terapêutico nas intensidades 0 W/cm² e 2,0 W/cm²promoveu estímulo para formação dos colágenos tipos I e III na área da lesão por primeira intenção.

Desenvolvimento de instrumentação para aplicação e avaliação do treinamento locomotor com suporte parcial de peso / Development of instrumentation for application and assessment of locomotor training with partial body weight support

O treino locomotor com suporte parcial de peso (TLSP) é um método para reabilitação da marcha que consiste em suspender o indivíduo sobre uma esteira enquanto seus membros inferiores são movimentados passivamente. Para aplicar o TLSP de forma apropriada, é preciso que a descarga de peso sobre membros inferiores seja controlada e monitorada. O objetivo deste trabalho foi desenvolver um sistema de suporte de peso (SSP) capaz de medir descarga de peso sobre membros inferiores e superiores. Além disso, instrumentação para medição do ângulo do joelho, contato do pé e eletromiografia foi desenvolvida para avaliação do treino. O SSP foi construído com um sistema de polias, cabo de aço, guincho manual, uma célula de carga fixa ao cabo e duas outras em apoios para as mãos adaptados a uma esteira elétrica. Eletrogoniômetros e footswitches foram construídos para o sistema de medição, e uma plataforma de aquisição de sinais foi desenvolvida em ambiente LabVIEW®. As células de carga e os eletrogoniômetros foram calibrados e testados. Um ensaio piloto foi realizado com um indivíduo saudável a uma velocidade de 1,5 km/h com descarga de 60% do peso corporal sobre membros inferiores. O SSP desenvolvido apresentou erro menor que 1,5% e forneceu medidas das descargas de peso sobre membros superiores e inferiores. Ele permitiu analisar assimetria sobre membros superiores, o que pode ser importante na reabilitação neurológica. O spadrões cinemáticos e eletromiográficos fornecidos pelo sistema de medida foram semelhantes aos mostrados na literatura. A patente do sistema foi requerida junto ao INPI sob o protocolo n° 0000280904043771.

The locomotor training with partial weight support (LTPWS) is a method for gait rehabilitation which consists in suspending the individual over a treadmill while its lower limbs are passively moved mimicking the gait cycle. In order to properly apply LTPWS, the weight load over lower limbs must be controlled and monitored. The main aim of this work was to develop a partial weight support system (WSS) able to measure lower and upper limb loading. Also, instrumentation for measuring knee angle, foot contact and EMG data was developed for training assessment. The WSS was constructed with a pulley system, a steel cable, a manual winch, aload cell fixed at the cable and two other load cells fixed to handrails built on an electrical treadmill. For the measuring system, electrogoniometers and footswitches were constructed and a signal acquisition platform was developed on LabVIEW® environment. The load cells and electrogoniometers were calibrated and tested. A pilot test with a healthy individual was carried out at a speed of 1.5 km/h with a load of 60% of the body weight, over lower limbs. The developed WSS exhibited an error below 1.5% and was able to measure upper and lower limb weight load. It allows analyzing upper limbs loading and lateral unbalance, what might be important for neural rehabilitation. The measuring system was able to provide kinematic and electromyographic patterns similar to those shown in the literature under similar conditions. A patent request was submitted to the INPI under protocol nº 0000280904043771.