Effects of ROI-C Cervical Implantation on Biomechanics of Cervical Vertebra / 医用生物力学

Objective To investigate the influence of ROI-C cervical implantation in the C5-6 segment on the C3-7 range-of-motion (ROM), biomechanical properties of the intervertebral disc and the vertebral body, and the mode of force transmission. Methods Two types of surgeries, ROI-C implantation and autograft fusion with plate fixation, were considered to establish the finite element model of cervical C5-6 segment degeneration. The ROM of C3-7 during flexion, extension, lateral bending, and axial rotation, as well as stress distributions on the adjacent discs, vertebral body, and implanted devices under two procedures, were analyzed. Results ROI-C implantation had a relatively small influence on the ROM of the adjacent segment. The stress on the vertebral discs was reduced, but the stress on the vertebral body increased significantly, with the C5 vertebral body stress increasing by 251%. In the fusion surgery model, the ROM of the surgical segment was reduced by 86%-91%, while the ROM of the adjacent segments and the stress on the vertebral disc and vertebral body increased significantly. Conclusions ROI-C implantation surgery has a relatively small influence on the cervical ROM and the intervertebral disc, and it has a greater impact on the vertebral body. The research findings provide a theoretical basis for the design of operation plans and clinical studies on ROI-C implantation and autograft fusion with plate fixation.

Clay-Shoveler's Fracture in an 18-Year-Old Cheerleader: A Case Report

Clay-Shoveler's fracture refers to a fracture that is solely developed on the spinous process of the cervical spine or the thoracic vertebrae. This fracture rarely occurs during sporting activities. In this case, an 18-year-old female developed the fracture on the spinous process of the 7th cervical spine and 1st thoracic vertebrae due to the repetitive practice of cheerleading. The patient's pain was improved by wearing a support device and taking an anti-inflammatory analgesic drug and muscle relaxant. Her case is being followed-up at the outpatient department.

Imaging measurement and clinical significance of the angle between the axis of pedicle and the plane of lamina in lower cervical vertebra / 中南大学学报(医学版)

Objective:To explore the imaging measurement and clinical significance of the angle between the axis ofpedicle and the plane of lamina in lower cervical vertebra.Methods:Three dimensional reconstruction of CT scan was performed in 30 patients with cervical deformity,and the angle between the axis ofpedicle and the plane of lamina was measured with the specific reconstructed CT image of C3-C7.Results:1) The left and right transverse angle of C3-C7 between the axis of pedicle and the ipsilateral plane oflamina were 98.3°±6.3°,98.0°±5.1°,97.5°±6.9°,95.1°±5.0°,85.8°±5.4°and 96.7°±8.2°,98.7°±7.1°,97.8°±3.6°,93.2° ±6.2°,86.8° ±5.7°,respectively,which showed a gradual decreasing trend.Meanwhile the angle ofC3-C6 was more than 90 degrees and C7 was less than 90 degrees.In addition to C6 with C3 and C7 with other segments,the rest of the differences between the sections was not statistically significant (all P＞0.05).2) The left and right transverse angle of C3-C7 between the axis of pedicle and the pedicle of vertebral arch of lamina were 0.2°±4.5°,1.2°±7.2°,-0.8° ±6.8°,-3.3°±5.4°,-14.7° ±4.0° and-1.6°±5.4°,1.9°±4.6°,-0.5° ±6.0°,-4.6° ±5.3°,-13.7°±3.4°,respectively,which showed a first increasing and then reducing trend.Meanwhile the angle of C4 was maximum angle.In addition to C6 with C3;C6 with C4,and C7 with other segments,the differences between the sections was not statistically significant (all P＞0.05).3) The left and right sagittal angle of C3-C7 between the axis of pedicle and the ipsilateral plane of lamina were 77.7°±7.6°,77.0°±7.1°,85.3° ±8.4°,94.1°±2.2°,94.9°±3.8° and 78.5° ±7.1°,76.2° ±6.2°,86.4°±6.4°,94.0°±2.7°,95.6°±3.8°,respectively,which showed a gradual increasing trend.The angle of C3-C4 was less than 90 degrees.Cs showed large variation and C6-C7 was more than 90 degrees.In addition to C3 with C4 and C6 with C7,the differences between the sections was statistically significant (all P＜0.05).There was no significant difference between the two sides of the above indexes (all P＞0.05).Conclusion:In low cervical vertebra,there is a certain angle relationship between the axis of pedicle and the plane of lamina,which can provide reference for the clinical determination of angle of pedicle screw insertion.