BACKGROUND: Percutaneous vertebroplasty (PVP) is usually used for osteoporotic thoracolumbar fractures,which has various advantages such as easy to operate, short operation time, less trauma, rapid recovery,analgesic effect and so on. But its application is restricted due to nerve compression symptoms and pulmonary embolism caused by bone cement leakage. Thereafter, how to reduce the leakage of bone cement is an issue of concern.OBJECTIVE: To investigate the relationship between the lumbar quantitative computed tomography (QCT) values and contrast agent dispersion in osteoporotic thoracolumbar fractures. METHODS: Sixty cases of osteoporotic thoracolumbar fractures undergoing PVP were enrolled, and received QCT examination before surgery, and contrast agent was injected intraoperatively. X-ray examination was conducted to detect the bone mineral density, contrast agent dispersion and leakage of bone cement, and the relationship between the lumbar QCT values and contrast agent dispersion as well as leakage of bone cement.RESULTS AND CONCLUSION: (1) There were 110 vertebral fractures, and 74 vertebrae with contrast agent diffusing more than vertebral midline, accounting for 67.3%. There was significant difference in the contrast agent dispersion among groups (P < 0.05). (2) The bone cement leakage showed no significant difference among groups after injected with bone cement by unilateral or bilateral approach (P > 0.05). (3) These results suggest that contrast agent dispersion in osteoporotic thoracolumbar fractures has a certain relationship with the lumbar QCT values, and lumbar QCT values with more contrast agent dispersion, but the lumbar QCT values have no correlation with bone cement leakage. Therefore, choosing a appropriate approach based on the QCT values and contrast agent dispersion can reduce leakage and improve the safety of PVP.

Objective To explore the clinical value of neurography and nerve root sealing in treatment of multilevel lumbar spinal stenosis with lumbar instability using Endo-P/TLIF.Methods A total of 60 patients with multi-segment lumbar spinal stenosis and lumbar instability hospitalized in our hospital were included in this study From January 1,2022 to June 21,2022.All patients underwent nerve root closure angiography before surgery to confirm the responsible segments,and then the responsible segments were treated with Endo-P/TLIF.The patients were followed up for 6 months.The basic information on the age,gender,course of disease,surgical time,intraop-erative bleeding,hospitalization time,and off-bed ambulation time was collected.Then the data on VAS score,ODI score,JOA score,lumbar lordosis angle,intervertebral height,dural cross-sectional area,sacral inclination angle,pelvic projection angle,and pelvic inclination angle before,right after,3 months and 6 months after the operation were calculated.The number of responsible segments indicated by MRI and confirmed by nerve root closure angiography and the number of the single segment,double segments,3 segments,and above finally decompressed were statisti-cally analyzed.Results All patients went through the surgery safely.During the 6-month follow-up,one patient did not return to the hospital for consultation on time,and one patient was out of contact.Finally,the follow-up data of 58 patients were completely collected for statistical analysis.Fifty-five cases were remarkably improved,2 better,and 1 moderately,6 months after the operation,with a total effectiveness rate of 100%.The number of unilateral and bilateral single responsible segments confirmed by nerve root angiography and sealing was significantly larger than by MRI(P<0.05),but the number of unilateral and unilateral double,or multiple responsible segments was signifi-cantly smaller(P<0.05).There were statistically significant differences in terms of postoperative VAS score,ODI score,JOA score,VAS score,ODI score,JOA score,lumbar lordosis angle,intervertebral height,dural cross-sectional area,sacral inclination angle,pelvic inclination angle as compared to the preoperative data(P＜0.05).The pelvic projection angle was insignificantly improved as compared to the preoperative condition(P ? 0.05).Conclusion The accurate diagnosis with selective neurography and nerve root sealing improves the confirmation of responsible nerve segments before operation.Base on the accurate diagnosis,multi-segment lumbar spinal canal stenosis with lumbar instability can be effectively treated with Endo-P/TLIF,the responsible segment decompressed,trauma and bleeding reduced,hospital stay shortened,spinal physiological curvature well recovered,and clinical efficacy improved.Therefore,the method is worthy of extensive application in clinical practice.

BACKGROUND:Taking into account the stability of spinal fixation,the preferred approach for lateral lumbar interbody fusion is commonly the utilization of posterior bilateral pedicle screws,typically performed in two stages.An alternative method involving the posterior approach of unilateral fixation using lateral vertebral nail rods in the lateral decubitus position has shown potential for enhanced mechanical stability.This technique also offers additional advantages such as reduced operation time,lowered risks,and decreased costs,making it a promising area for further investigation. OBJECTIVE:To compare the biomechanical effect of lateral lumbar interbody fusion with four different types of posterior instruments. METHODS:A validated L3-5 finite element model was modified to simulate four different types of lateral lumbar interbody fusion:Model A:posterior bilateral pedicle screw fixation;Model B:posterior unilateral pedicle screw fixation;Model C:lateral bilateral screw fixation;Model D:lateral unilateral screw fixation.The stability in the range of physiological motion,and the stress difference of screw fixation and interbody fusion apparatus were compared among the models. RESULTS AND CONCLUSION:(1)When compared with the intact model,all reconstructive models displayed decreased motion range at L4-5.Model A had a more obvious range of motion decline.(2)In the flexion,lateral flexion and axial rotation,the differences between the peak stress of the lateral screw fixation and the peak stress of the posterior screw fixation were more than 67.74 MPa,80.10 MPa and 43.95 MPa,respectively.(3)In terms of internal fixed stress distribution in different reconstructed models,the stress distribution of Model A and Model B screws was mainly concentrated in the body of the pedicle screw,while the peak stress of Model C and Model D screws was mainly concentrated in the tail of the screw.(4)It is suggested that Model A could obtain the best stability and reduce the risk of cage sinking and displacement.Model B could also provide better stability,and could be a choice for lateral fusion on the premise of ensuring stability and fixation.(5)Besides,Model C could achieve the same effect as Model D when the lateral road screw was selected.However,patients with lumbar instability should be cautious to choose unilateral lateral internal fixation,and excessive extension should be avoided to reduce the possibility of screw loosening and fixation fatigue.

BACKGROUND:The specific molecular mechanism of the transformation from normal healthy people to acute cervical spondylotic radiculopathy has not been clear,which needs to be further studied. OBJECTIVE:To investigate the differential expression of serum proteomics between normal healthy people and patients with acute cervical spondylotic radiculopathy,and to find and identify potential specific serum markers between them. METHODS:The serum samples of eight patients with acute cervical spondylotic radiculopathy and eight normal healthy people were collected,and the proteomic screening and analysis were performed by tandem mass tag combined with liquid chromatography-tandem mass spectrometry technology,in order to explore and identify serum proteins differentially expressed in patients with acute cervical spondylotic radiculopathy. RESULTS AND CONCLUSION:A total of 183 significantly differential proteins were screened by tandem mass tag technology,and 11 significantly differential proteins were identified(P＜0.05).Compared with normal healthy people,three differential proteins were significantly up-regulated,including human leukocyte antigen-A,secretoglobin family 1a member 1,and protein 4-hydroxyphenylpyruvate dioxygenase,and seven differential proteins were significantly down-regulated,such as immunoglobulin heavy constant gamma 3,skin factor,and myosin light chain 3,in patients with acute cervical spondylotic radiculopathy.Gene ontology enrichment analysis showed that these differential proteins participated in antigen binding,immunoglobulin receptor binding and other molecular functions.Protein-protein interaction analysis showed that among the common differential proteins between normal healthy people and patients with acute cervical spondylotic radiculopathy,HLA-A,HPD,PSMA3,DMKN,SCGB1A1,and MYL3 were located at the nodes of the functional network,and were closely related to the systems of body immunity,cellular inflammatory response,energy metabolism,and mechanical pressure.The significantly differential proteins HLA-A,HPD and MYL3 were verified by western blot,and the results were consistent with those of proteomics.To conclude,tandem mass tag combined with liquid chromatography-tandem mass spectrometry technology can be used to find the differentially expressed proteins in serum between normal healthy people and patients with acute cervical spondylotic radiculopathy.It is preliminarily believed that HLA-A,HPD and MYL3 may be specific serum markers of acute cervical spondylotic radiculopathy,providing a new direction for further research on its pathogenesis.