RESUMO
Resumen La base fundamental de la valoración médico legal de un individuo es establecer la relación de causalidad entre la historia narrada por el mismo y los hallazgos documentados. La biomecánica del trauma es una herramienta que permite dilucidar dicha concordancia, ya que su estudio involucra los mecanismos de trauma implicados en la génesis de las distintas lesiones. Este artículo consiste en una revisión bibliográfica y crítica de la literatura actual en materia de etiopatogenia de las lesiones en hombro por su alta incidencia laboral y capacidad de generar secuelas.
Abstract The basis of the forensic evaluation of an individual is to establish the relationship of causality between the story that has been told by the patient and the documented findings. The study of injury biomechanics is a tool that helps to clarify said concordance, since it involves the trauma mechanisms that are implied in the genesis of the different lesions. This article consists of a bibliographical revision and critique of the current literature about the etiopathogenesis of the shoulder lesions, since they are frequent in the work place and can generate sequels.
Assuntos
Humanos , Ombro , Riscos Ocupacionais , Bursite , Médicos Legistas , Lesões de Bankart , Lesões do Manguito Rotador , Lesões do Ombro , Medicina Legal , Medicina do TrabalhoRESUMO
Objective To explore the brain injury mechanism and enrich the database of human finite element (FE) biomechanical model by developing the FE model of one-year-old toddler head. Methods Based on CT data from Chinese one-year-old toddler head with substantial and detailed information, the head model with detailed anatomical structure was constructed by using the medical software Mimics to get the head geometry data, as well as the reverse engineering software to divide NURBS surface and build the geometric model. Finally, the FE pre-processing software was used mesh the model. The FE model of one-year-old toddle head was validated by data from anatomic and cadaver experiments, and was used for preliminary analysis on damage mechanism of one-year-old toddler head. Results The FE model of Chinese one-year-old male toddler head was developed, which included and distinguished the gray matter and white matter of brain and cerebellum, hippocampus, fontanel, sagittal suture, coronal suture, brainstem and ventricles. The cadaver head static compression experiments and drop experiments were reconstructed by using this head model, and the results showed that the FE model of head had similar mechanical properties with the cadaver, which proved the validity of the FE model. Simulation results showed that skull stiffness and skull injury severity varied with different compression rates. Conclusions The FE model of one-year-old toddler head with detailed anatomical structures is of great biofidelity. The FE head model can be used to further investigate the detailed injury mechanism of deep brain tissues, especially for the closed craniocerebral injury, which provides an effective way and tool for the related research and clinical application.
RESUMO
Objective In order to fully reconstruct the accident by utilizing pedestrian injuries information gained from the car-pedestrian collision, a new method based on finite element simulation and genetic neural network to deduce the car-pedestrian collision parameters in reverse is proposed. Methods Crash simulations from different contact angles (back, left, front, right) at different impact speeds (25, 40, 55 km/h) were conducted by using Hyperworks and LS-DYNA, so as to obtain the head injury criterion (HIC) value and the maximum velocity of the thoracic wall. According to the criteria of injury biomechanics, the severities of the pedestrian head and thorax and corresponding injury locations were analyzed and set as predictors, and the predictive values of collision parameters were then acquired by using genetic neural network. Finally, this method was verified by two car-pedestrian accidents with the video and exact collision parameters. Results For both cases of the car-pedestrian accidents, the car speeds at the collision of pedestrian were 54 and 49 km/h, respectively, and the car-pedestrian contact angles were both 180°. While according to the pedestrian injuries information, the predictive values of the car speeds at the collision of pedestrian were 51 and 43 km/h, and the predictive values of the car-pedestrian contact angles were 184° and 169°, respectively. The reconstruction accuracies of two cases were 0.94 and 0.88. Conclusions The proposed method in the study can be used to predict car-pedestrian collision parameters efficiently and accurately by utilizing the pedestrian injuries information, which provides a new method for cause analysis and responsibility recognition, as well as theoretical references for the treatment and protection of head and thoracic injuries occurred in the car-pedestrian collision.