Reconstructing the three-dimensional finite element model of compression fracture of T_(12) based on the 210-layer consecutive CT DICOM format images from one patient of compression fracture of T_(12) to simulate the hyperextending. Bound the lower of T_(12), a vertical traction at the top of T_(11)and a 3.0 cm-displacement toward the vertebra by three steps at the top of spinous process of T_(11), T_(12) and L_1 was provided. The procedure began computing to reed the results about dynamic biomechanical characteristics of anterior longitudinal ligament. A realistic appearance and full biomechanical properties 3D finite element model of thoracolumbar spine compression fracture was established. The anterior longitudinal ligament was changed from relaxation to tension after hyperextending. The stresses of anterior longitudinal ligament were different when the hyperextending fulcrum was different. The treatment effect of thoracalumbar spine compression fracture by hyperextending is exact. The anterior longitudinal ligament plays an important role in the treatment. Finite element analysis of mechanism of traditional practices has many advantages, such as reliable experimental results, direct displaying results, saving resources and accurate simulation.

Objective:To assess the clinical value of helium-free magnetocardiography(MCG) in the diagnosis of coronary artery disease(CAD).Methods:A total of 213 patients with suspected CAD undergoing MCG in Beijing Anzhen Hospital were enrolled in the study. All patients underwent coronary CT angiography/invasive coronary angiography(CCTA/ICA) within 48 hours after MCG scanning. The parameters of MCG, including magnetic field multipolarization, magnetic field unipolarization, T-wave flattened, change in magnetic field distribution at TT segment, abnormal T-peak amplitude ration of maximum to minimum, significant movement of poles, magnetic field angle deviation and abnormal distribution of positive pole were used for the evaluation of the stenosis of coronary arteries.Results:Among 213 patients, MCG scanning was completed in 193 cases(90.6%), while 20 cases were excluded for various reasons. The CCTA/ICA results were taken as gold standard, the total coincidence rate of MCG with the degree of stenosis was 88.60%(95% CI: 83.25%-92.72%), the sensitivity and specificity of MCG in the diagnosis of CAD was 89.63%(95% CI: 83.21%-94.21%) and 88.23%(95% CI:78.12%-94.78%), respectively; the positive and negative predictive value were 93.80%(95% CI:88.72%-96.68%) and 81.08%(95% CI:72.15%-87.64%), respectively. Conclusion:MCG is highly accurate in the diagnosis of CAD, it may be widely used clinically as an non-invasive method free of radiation or contrast agent.