Résumé
Objective: To investigate the safety and effectiveness of pedicle screw implantation via vertebral arch-transverse pathway in clinical application by a prospective randomized controlled trial. Methods: Twenty-four patients who were admitted between May 2015 and June 2017 and met the selection criteria for thoracic pedicle screw fixation were included in the study. According to the random number table method, they were divided into the trial group (screw implantation via vertebral arch-transverse pathway) and the control group (traditional screw implantation technology), with 12 patients in each group. There was no significant difference between the two groups in age, gender, cause of injury, injured segment, and the interval between injury and operation (P>0.05). The time of screw implantation was recorded and compared between the two groups. The acceptable rate of screw implantation and the penetration rate of pedicle wall were calculated after operation. Results: The time of screw implantation of trial group was (5.08±1.74) minutes, which was significantly shorter than that of control group [(5.92±1.66) minutes], and the difference was significant (t=4.258, P=0.023). Patients in both groups were followed up 1-2 years, with an average of 1.5 years. During the follow-up, no failure of internal fixation occurred. At 1 week after operation, the screw implantation in trial group was rated as gradeⅠin 54 screws, gradeⅡ in 3 screws, and grade Ⅲ in 2 screws, with the acceptable rate of 93.61%. The screw implantation in control group was rated as gradeⅠin 40 screws, grade Ⅱin 10 screws, grade Ⅲ in 8 screws, and grade Ⅳ in 1 screw, with the acceptable rate of 84.75%. There was significant difference in the acceptable rate of screw implantation between the two groups (χ2=3.875, P=0.037). The penetration rate of pedicle wall in trial group was 8.47% (5/59), which was significantly lower than that in the control group [32.20% (19/59); χ2=4.125, P=0.021]. Conclusion: Compared with the traditional technique, the pedicle screw implantation via vertebral arch-transverse pathway can obtain a good position of the screw canal with higher accuracy and simpler operation.
Résumé
Objective To investigate the morphological regularity of the thoracic pedicle screw in 4 to 12 years old children by the digital technology,and to provide the theoreticl basis for thoracic pedicle screw fixation in children.Methods A total of 60 healthy children aged from 4 to 12 years old with computed tomography(CT) data of thoracic spine were divided into three groups by age,each group 20 cases.Then they were examined by MIMICS software and the parameters of pedicle width(PW),pedicle height(PH),the length of screw path(SL),e angle and f angle were measured.Results The pedicle width,pedicle height,the SL of the pedicle generally showed a rising trend with advancing age.There were significant differences in the PW,PH and LS between the three group(P0.05).E angle of the pedicle generally showed a decreasing trend with increasing vertebral order,and e angle of T11 to T12 showed negative angle.The f angle showed a wavy descending trend.Conclusion There was significant difference in correlation parameters of thoracic pedicle with increasing age in healthy children,which indicates that the pedicle screw fixation for the kind of children should be performed based on 'the Principle of individualization' to improve the success rate of surgery.
Résumé
Objective To evaluate the results of orthodontic micro- implant anchorage implantation by application of Spiral CT and three-dimensional reconstruction techniques,so as to explore its application value in assisting clinical diagnosis and treatment. Methods 20 orthodontic patients were implanted with 48 micro-planting screws. SOMATOM Sensation40/64 helical CT scan was performed . The axial unenhanced helical CT data were given multi-planar reconstruction (MPR),maximum intensity projection (MIP),volume rendering (VR) and surface multidimensional reconstruction (CPR) by using the Siemens 3D post-processing software. The axial scanning images and reconstructed images were compared, observed and analyzed . Results The planting results of 37 micro screws were satisfactory without injuring the vital tissues surrounding the root. The planting results of 11 micro-screw were not ideal, and these micro-screws were observed or reimplanted and got success. Spiral CT axial scan showed better the tooth root interval and the relationship between tooth root and the planting screws. VR can directly showed the overall relationship between the planting screws and teeth , jaw contour appearance. The relationship between the screw and tooth was showed satisfactorily by MIP which could rotate freely and observe from different angles. MPR could clearly show the structural relationships between micro-root planting screws and tooth root and surrounding tissues from the cross section, and could make up for the shortcomings of axial limitations, and was easy to measure the distance and tilt angle of the long axis . Conclusion Spiral CT and three-dimensional reconstruction can accurately show the jaw micro planting screw shape,location and spatial relationships with adjacent teeth , the image is clear,intuitive and definite,and spiral CT and three-dimensional reconstruction has high application value in orthodontics micro-implant anchorage clinic as a powerful auxiliary examination means.