Pediatric cardiac tamponade caused by metallic wire penetration into the heart: A case report and literature review

Thin, metallic wires can easily penetrate the gastrointestinal system if ingested and cause serious cardiac issues in children. We report a pediatric case of such an object that caused cardiac tamponade after lodging in the left ventricle. The wire was extracted without cardiopulmonary bypass and a full recovery was made. Cardiac issues after ingestion of foreign objects are rare but immediate surgery is required for resolution.

Osteotomia da ulna para correção cirúrgica de fratura de Monteggia negligenciada em criança com deformidade plástica da ulna. Relato de caso / Ulna osteotomy for surgical correction of neglected Monteggia fracture in a child with ulna bowing. Case report

Introdução: A luxação da cabeça do rádio com deformidade plástica da ulna, quando combinadas, configuram uma condição rara, e frequentemente não diagnosticada na urgência. Objetivo: Relatar um caso de fratura de Monteggia negligenciada em criança com defomidade plástica da ulna, tratada cirurgicamente com redução e fixação da cabeça dorádio, sem reconstrução do ligamento anular, e osteotomia da ulna. Relato do Caso: Paciente de 6 anos de idade, sexo masculino, vítima de queda ao solo com a mão espalmada, deu entrada em Unidade de Pronto Atendimento com queixa de dor no cotovelo direito. Paciente foi submetido à exames de imagem radiográficos do cotovelo interpretados peloexaminador como sem alterações. Duas semanas após, o paciente retornou mantendo dor, e foram solicitados exames de radiografia do antebraço, que evidenciaram presença de deformidade plástica da ulna associada à luxação da cabeça do rádio. Como tratamento, optou-se pela redução aberta e fixação da cabeça do rádio com fios metálicos, associado aosteotomia de flexão da ulna fixada com fio de Kirschnner. Evoluiu no pós operatório com consolidação da osteotomia, manutenção da redução da cabeça do rádio, e recuperação do arco de movimento total do cotovelo e antebraço. Conclusão: Pacientes pediátricos que se apresentam com dor no cotovelo, em decorrência de queda com a mão espalmada, devem ser minuciosamente avaliados quanto à possibilidade de deformidade plástica da ulna associada à luxação da cabeça do rádio. A osteotomia na ulna com fixação da cabeça do rádio, sem reconstrução do ligamento anular, trouxe bom resultado no tratamento de fratura de Monteggia negligenciada em criança com defomidade plástica da ulna. Palavras chave: Fratura de Monteggia, Ulna/deformidades, Fraturas da ulna, Osteotomia, Trauma, Criança, Pediatria Abstract Introduction: Dislocation of the radial head with ulna bowing, when combined, constitutes a rare condition, and often missed diagnosed. Objective: Report a case of neglected Monteggia fracture in a child with ulna bowing, treated surgically with reduction and fixation of the radial head, without reconstruction of the annular ligament, and osteotomy of the ulna. Case Report: A 6-year-old male patient, victim of falling to the ground, was admitted to the Emergency Department with complaints of pain in his right elbow. The patient was submitted to radiographic exams of the elbow, interpreted by the physician as normal. Two weeks later, the patient returned with pain, and radiographic exams of the forearm showed the presence of ulna bowing associated with dislocation of the radial head. As a treatment, we opted for open reduction and fixation of the radial head with metallic wires, associated with flexion osteotomy of the ulna. It evolved in the postoperative period with consolidation of the osteotomy, maintenance of the reduction of the radial head, and recovery of the total range of motion of the elbow and forearm. Conclusion: Pediatric patients who present with pain in the elbow, due to a fall, should be thoroughly evaluated for the possibility of ulna bowing associated with dislocation of the radial head. Ulna osteotomy with fixation of the radial head, without reconstruction of the annular ligament, brought good results in the treatment of neglected Monteggia fracture in a child with ulna bowing. Keywords: Monteggia fracture, Ulna/deformities, Ulna fractures, Osteotomy, Trauma, Child, Pediatrics

Design, Optimization and Experimental Verification of a Metal Rubber Isolator for Momentum Wheels

The inertial actuator, such as momentum wheels, is the key mechanical component of spacecraft for attitude stability and accuracy maintenance. However, the inertial actuators are under excessive vibration during the rocket launch phase. In order to prevent the inertial actuators from structural damage and equipment failure, isolating vibration from the base must be considered. Metal rubber (MR) is a kind of porous functional damping material, manufactured through the process of entangling, stretching, weaving and molding of metallic wires. With its excellent mechanical properties of high damping, designable stiffness and environmental adaptability, MR is widely used in the area of aerospace and aviation for vibration isolation. To this end, a method to design and optimize a MR isolator for momentum wheels is developed. The MR isolator consists of a transverse groove spring and MR in parallel. A FEM model coupling the transverse groove spring and the simplified momentum wheel is established to assist in the optimization of the configuration of the spring, and the goal is to minimize the frequency bandwidth of the first six modes. The influence of the parameters on the frequency of the first six modes is also discussed. The MR is then designed to provide damping and additional stiffness. Finally, the performance of the MR isolator is analyzed by simulation and verified through experiments.

Attractiveness of different esthetic orthodontic wires

ABSTRACT Objective: The aim of this study was to evaluate the attractiveness of different types of esthetic orthodontic wires by laypeople and dentists. Methods: Five different types of orthodontic wires were evaluated: three esthetic wires (Teflon-coated, epoxy resin-coated and rhodium-coated wires), and two metallic wires (stainless steel and NiTi), as control. Monocrystalline ceramic brackets were installed in the maxillary arch of a patient presenting good dental alignment. The five evaluated wires were attached to the orthodontic appliance with an esthetic silicone elastic and photographed. The photographs were evaluated by 163 individuals, 110 dentists and 53 laypeople. The data were statistically evaluated by two-way ANOVA and one-way ANOVA, followed by Tukey tests. Results: There was a statistically significant difference in the attractiveness among the wires evaluated; the most esthetic was the rhodium-coated wire, followed by the epoxy resin-coated wire and, finally, the Teflon-coated wire, with no significant difference from the stainless steel and NiTi control archwires. There was no significant difference between the groups of evaluators. Conclusion: The most attractive was the rhodium-coated wire, followed by the epoxy resin-coated wire and, finally, the least attractive wire was the Teflon-coated wire, without statistically significant difference to the stainless steel and NiTi wires, used as control.

Using antibacterial fibers and metallic wires to make woven fabrics used as smart diapers

Cloth diapers also known as eco-diapers, traditional sandwich-structured eco-diapers are composed of top and bottom layers that are made of cotton or polyester nonwoven fabrics. On account of the hydrophilic bottom layer, urine permeates when the water absorption reaches saturation. In this study, polypropylene is melt-blown into hydrophobic polypropylene nonwoven fabrics to be used as the top and bottom layer. Polypropylene is hydrophobic but after being fabricated into nonwoven fabrics, the porous structure enables the urine to leak to the absorbent interlayer of eco-diapers. Hence, the top layer of diaper does not contain urine, which makes smart diapers more comfortable than cloth diapers that are made of cotton or other moisture-absorbent materials. Moreover, the sensing mechanism via Bluetooth module can detect the water content of the interlayer with a view to improving the demerit of urine leakage. The interlayer is the sensing layer that has antibacterial function. Two types of antibacterial yarns are treated by zinc oxide and silver ions. The yarns are fabricated into antibacterial woven fabrics, after which the antibacterial properties of fabrics are investigated with quantitative and qualitative tests. Next, two parallel metallic wires are assembled in order to trigger short circuit when sensing moisture, thereby obtaining different electric resistance based on different moisture levels. Furthermore, the miniature senor can signify the cellular phones or buzzers when the two metallic wires generate electrical resistance due to the presence of urine. The metallic wires are silver-plated copper yarns, stainless steel fibers, and copper fibers, which possess different electric resistance for the corresponding miniature sensors. This study proposes an efficient manufacture of smart diapers that require only a combination of woven fabrics and two metallic wires to sense moisture, the design of which can be encompassed in diverse fields.