Modified pedicle screw fixation under guidance of stress analysis for cervicothoracic junction: Surgical technique and outcomes.

BACKGROUND: In cervicothoracic junction, the use of strong fixation device such as pedicle screw placement is often needed. OBJECTIVE: The current study aimed to evaluate the accuracy and safety of pedicle screw placement using stress conduction analysis in the clinical application. METHODS: We retrospectively collected patients who underwent pedicle screw internal fixation in cervicothoracic junction. Patients were divided into conventional nail placement (Group A) and modified pedicle screw implantation under guidance of stress analysis (Group B) according to the methods of pedicle screw placement. The accuracy of pedicle screw placement was assessed by computed tomography (CT) examination, and the success rate was calculated. RESULTS: A total of 80 patients who underwent pedicle screw internal fixation in cervicothoracic junction were included. There were no obvious differences in baseline characteristics between two groups. The success rate of total screw placement, cervical spine screw placement and upper thoracic spine screw placement in Group B was higher than those in Group A (P< 0.001, P= 0.005, P= 0.008). Additionally, Heary Grade I in the Group B was higher than Group A (P= 0.001). CONCLUSION: Stress analysis-guided technique can increase the accuracy of pedicle screw placement. Importantly, it meets the requirements of internal fixation of the cervicothoracic junction.

Analysis of spinal stress analysis application in determining method for the pedicle screw placement under the guidance of X-Ray.

OBJECTIVE: To evaluate the accuracy of a novel guidance method of pedicle screw implantation determined by spinal stress. METHODS: We retrospectively analyzed patients underwent pedicle screw internal fixation between January 2015 and August 2018 in our hospital. Patients were divided into two groups according to the methods of pedicle screw implantation namely, the conventional nail placement and novel guidance method of pedicle screw implantation determined by spinal stress. Accuracy of spinal pedicle screw placements was evaluated using intraoperative and postoperative X-ray computed tomography (CT) examination and intraoperative touch of nerve root dissection pedicle bone. The success rate of intraoperative one-time screw placement was calculated according to Heary classification I. RESULTS: A total of 785 patients underwent pedicle screw internal fixation were retrospectively analyzed. Among them 384 patients were treated using conventional nail placement (Group A) and 401 patients were treated using the technique according to analysis of spinal stress (Group B). There was no significant difference in terms of the characteristics between two groups. There were significant differences in terms of the success rate of total of screw placement (88.7% vs. 96.2%, P < 0.001) including thoracic screw placement (87.8% vs. 94.5%, P = 0.003) and lumbar screw placement (88.8% vs. 96.5%, P = 0.001) for Group A and Group B, respectively. CONCLUSIONS: Using the novel guidance method of pedicle screw implantation determined by spinal stress might improve the accuracy of pedicle screw implantation.

Applications of the scoliosis width-to-length ratio for guiding selection of the surgical approaches of degenerative lumbar scoliosis.

BACKGROUND: There does not exist a comprehensive parameter for guiding selection of short or long segment fusion for degenerative lumbar scoliosis (DLS). The aim of our study was to investigate the applications of the width-to-length ratio in guiding selection of the surgical approaches for DLS. METHODS: A retrospective analysis was performed of 142 patients with DLS who underwent operative treatments from July 2000 to January 2012. The scoliosis width-to-length ratios were measured and used as a grouping criterion of surgical approaches. The Oswestry disability index (ODI) was used to evaluate the clinical outcomes. Radiological parameters such as Cobb's angle of main curve, Cobb's angle of compensatory curve were all measured. RESULTS: For patients with width-to-length ratio less than 0.36, the short segment group had better short-term postoperative outcomes with regard to Cobb's angle of main curve, Cobb's angle of compensatory curve and ODI scores compared to the long segment group. However, for patients with width-to-length ratio greater than 0.36, the postoperative outcomes for the long segment group were better compared to the short segment group. CONCLUSIONS: The scoliosis width-to-length ratio can provide a comprehensive preoperative assessment of the severity of the DLS and guiding selection of a therapeutic treatment regimen. Further studies with a larger number of samples and longer term of follow up are warranted.

Preliminary identification of palaeofloods with the alkane ratio C31/C17 and their potential link to global climate changes.

A major challenge in palaeohydrology is the extraction of continuous palaeoflood information from geophysical records. A high-resolution sediment core off the Minjiang estuary area in the Taiwan Strait, SE China, records the sedimentation history from approximately 1660 to the present. The alkane ratio C31/C17, a classic organic geochemical indicator of terrestrial/aquatic matter, peaks in the layers dating as 1876-1878 and 1968-1970, suggesting the large terrestrial input to the Minjiang estuary area by huge flood transporting during the each peak interval. Historical archives are consistent with this interpretations and record catastrophic floods in the Minjiang River during both intervals. Furthermore between 1876-1878 there were floods in southern China and droughts in northern China, as well as throughout Asia, Africa, Australia, and the Americas. The 1876-1878 catastrophic flood of the Minjiang River may therefore has been the local response to global climate anomalies during that time interval.

[Sequential drugs treatment for central pain following spinal cord injury].

OBJECTIVE: To investigate methods and therapeutic effects of sequential drugs treatment for central pain following spinal cord injury. METHODS: A total of 28 patients suffered from central pain following spinal cord injury were treated with sequential drugs from 1994 to 2008, including 23 males and 5 females, ranging in age from 25 to 59 years (mean 42 years). According to the patients' response to drugs, the therapy grade was adjusted step by step until the pain was relieved. Basing on VAS scores before and after drugs treatment, analgesic effect was evaluated. The first grade drugs: COX-2 inhibitors. The second grade drugs: Tricyclic antidepressant drugs (Amitriptyline) + COX-2 inhibitors + Carbamazepine. The third grade drugs: Tricyclic antidepressant drugs (Amitriptyline) + Gabapentin + Neurotropin/COX-2 inhibitors. RESULTS: The pain of all of 28 patients was relieved to different extent. The VAS scores decreased by 23.3 +/- 1.2 in the first grade drugs treatment group. The VAS scores decreased by 54.5 +/- 3.8 in the second grade drugs treatment group. The VAS scores decreased by 65.8 +/- 5.1 in the third grade drugs treatment group (P<0.05). CONCLUSION: The sequential drugs treatment for central pain following spinal cord injury has a good analgesia effect and little adverse reaction.

[Clinical application of atlantoaxial pedicle screw internal fixation for treatment of atlantoaxial dislocation].

OBJECTIVE: To investigate the clinical effect of atlantoaxial pedicle screw internal fixation for treatment of atlantoaxial dislocation. METHODS: Sixteen patients with atlantoaxial dislocation were treated from Dec. 2005 to June 2007, included 10 males and 6 females, aged from 38 to 45 years old (means 40.5 years). Among them 12 patients combined with nerve injury, according to ASIA grade: there were 3 cases in grade B, 5 cases in grade C, 4 cases in grade D. All patients received preoperative CT, radiograph and skull traction. Intraoperative posterior approach general spine pedicle screw-rod orthopaedics fixation system used and iliac bone block were implanted in space of posterior atlantal arch and axial vertebral plate. The outcome and complications were observed in the near future. RESULTS: There was no vascular or neural injury found. The patients were followed up for 12 to 24 months (means 18 months). All head pain, acid storm symptoms were improved after operation. According to the Odom's clinical efficacy evaluation standard, 12 cases were excellent, 4 were good. Eleven cases of 12 with nerve injury recovered significantly. By ASIA classification: 1 cases was in grade B, 2 cases were in grade C, 5 cases were in grade D, 4 cases were in grade E. No looseness or breakage of screw occurred. Bony fusion was achieved in all cases. CONCLUSION: Posterior approach atlantoaxial pedicle screw internal fixation have the advantages of direct screw placement, short-segment fusion, intraoperative reduction, fixation reliable, high fusion rate, and it can restablish the upper cervical vertebrae stability and help to recover the spinal cord and nerve function.