Optimal trajectory and insertion accuracy of sacral alar iliac screws

Objective: The aim of this study was to analyse the optimal trajectories for sacral alar iliac screws (SAISs) in a Japanese patient population and the clinical assessment of insertion accuracies. Methods: The ideal trajectories of SAISs, starting from 2 mm medial to the apex of the lateral sacral crest on the midline between S1 and S2 dorsal foramina, were measured in 80 consecutive spinal disease patients (40 males and 40 females; average age: 67.4 ± 8.1 years) using three-dimensional computed tomographic image software. Following these anatomic analyses, accuracies of 32 inserted SAISs in consecutive patients, who underwent long spinal posterior fusion, were investigated clinically. Results: Lateral angulations of optimal SAIS trajectories in males (left: 37.9; right: 37.7) were significantly larger than those than in females (left: 32.8; right: 32.4). Caudal SAIS angulations for females (left: 33.4; right: 33.9) were significantly larger than those in males (left: 27.5; right: 28.0). The 32 SAISs (100 mm long and 9 mm in diameter) assessed clinically were accurately inserted on optimal trajectories. Conclusion: The optimal trajectories of SAISs in a Japanese patient population are more lateral in males and more caudal in females. This study examines the clinical safety and accuracy of SAIS insertion on these optimal trajectories. Keywords: Sacral alar iliac screw, Optimal entry point, Optimal trajectory, Accuracy, 3D C

CO2 Capture Test for A Moving-bed System Utilizi g Low-temperature Steam

AbstractIn the process of capturing CO2 from flue gas (combustion exhaust gas), the lowering of CO2 capture energy is considered a significant issue. If some or all of the CO2 capture energy can be compensated with the waste heat, a significant energy saving is possible. In our proposed CO2 adsorption process, because the CO2 is captured using low-temperature steam, an energy-s ving process that makes it is easy to utilize the waste heat can be created. In this paper, we conduct bench tests aimed at developing a mo ing-bed system suitable for large-scale plants in order to verify the performance of the adsorbent. The results demonstrated that an moving-bed system could be established to capture 1.6t/day of CO2 from coal combustion exhaust gas