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find Author "YANG Xi" 23 results
  • Research progress on the influence of Modic changes on lumbar interbody fusion and its treatment measure

    Objective To review the research progress of Modic changes and its influence on lumbar interbody fusion. Methods The domestic and foreign literature related to Modic changes and its influence on lumbar interbody fusion was extensively reviewed. The etiology of Modic changes was summarized, and the treatment measures of Modic changes on lumbar interbody fusion were discussed. Results The etiology of Modic changes is not clear, which may be related to mechanical factors, autoimmune factors, low toxic infection factors, and genetic factors. Modic changes may lead to fusion failure and cage subsidence after lumbar interbody fusion. Preoperative evaluation of endplate sclerosis, reduction of iatrogenic endplate injury, fine operating of intervertebral space, management of osteoporosis, and selection of appropriate cage can prevent or reduce fusion failure or cage subsidence. Conclusion Modic changes may lead to fusion failure and cage subsidence after lumbar interbody fusion, and active perioperative intervention of Modic changes is helpful to improve the clinical prognosis.

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  • Analysis on the Relationship between Reflux Esophagitis and Helicobacter Pylori Infection

    目的 探讨和分析反流性食管炎与幽门螺杆菌感染之间的关系。 方法 回顾性分析2009年1月-2011年11月间胃镜确诊为反流性食管炎334例,所有患者均行快速尿素酶试验;其中反流性食管炎合并消化性渍疡57例,慢性非萎缩性胃炎102例。 结果 反流性食管炎的幽门螺杆菌感染率为21.6% ,在幽门螺杆菌感染阳性的患者中最多见并发消化性溃疡,而在幽门螺杆菌感染阴性的患者中最多见并发慢性非萎缩性胃炎,解剖结构和动力障碍性疾病绝大多数并发于幽门螺杆菌阴性患者。A和B级反流性食管炎的幽门螺杆菌感染阴性的患者多于幽门螺杆菌感染阳性的患者。在A级反流性食管炎中幽门螺杆菌感染率28.0%,B级为8.4%,C+D级为0.0%。 结论 反流性食管炎中幽门螺杆菌感染率低,幽门螺杆菌阳性的反流性食管炎多并发于消化性溃疡,提示幽门螺旋杆菌对反流性食管炎发病有一定保护作用。

    Release date:2016-09-08 09:12 Export PDF Favorites Scan
  • Finite element analysis of biomechanics of degenerative lumbar scoliosis under six kinds of motion conditions

    ObjectiveTo completely establish a three-dimensional (3D) simulation model of degenerative lumbar scoliosis (DLS) with the whole lumbar segments, then to analyze the biomechanical changes of the scoliosis segments by finite element analysis.MethodsA case of DLS patient was selected with L1-5 segments of CT scanning data, which was imported into MIMICS 15, SolidWorks, Hyper-Mesh software to establish a 3D simulation model, and ANSYS 15 was used to analyze the model. At the same time, different material properties and boundary loading conditions were assigned to various structures to simulate the actual human body conditions.ResultsThe 3D model built a total of 856 154 units and 232 850 nodes, including the reconstruction of fine vertebral bodies, intervertebral disc tissue, structure of various ligaments and joint cartilages. Under the load and torque, the range of whole lumbar segments was decreased, in the stress distribution on the four discs: the L2/3 intervertebral disc stress value (3.320 MPa) > L 4/5 intervertebral disc stress value (0.783 MPa) > L 3/4 intervertebral disc stress value (0.551 MPa) > L 1/2 intervertebral disc stress value (0.462 MPa). The stress distribution of the vertebral body showed that, L5 vertebral stress (34.0 MPa) > L 4 (33.6 MPa) >L 3 (30.0 MPa) > L 1 (23.3 MPa) > L 2 (22.4 MPa).ConclusionThe range of motion of the six degrees of freedom of the lumbar spine in DLS is decreased, the local stress distribution of the lumbar spine is abnormal, and the abnormal stress changes of the apical vertebral body and the top intervertebral disc may be the biomechanical basis for the occurrence or progression of DLS.

    Release date:2018-09-25 02:22 Export PDF Favorites Scan
  • Research progress of three-dimensional printing technology for clinical application in intervertebral fusion region

    With the development of three-dimensional (3D) printing technology, more and more researches have focused on its application in the region of intervertebral fusion materials; the prospects are worth looking forward to. This article reviews the researches about 3D printing technology in spinal implants, and summarizes the materials and printing technology applied in the field of spinal interbody fusion, and the shortcomings in the current research and application. With the rapid development of 3D printing technology and new materials, more and more 3D printing spinal interbodies will be developed and used clinically.

    Release date:2018-09-25 02:22 Export PDF Favorites Scan
  • Precise diagnosis and treatment of spastic cerebral palsy

    ObjectiveTo summarize the advancement of precise diagnosis and treatment for spastic cerebral palsy in recent years.MethodsThe literature and own experiences were reviewed, and the surgical method, precise diagnosis, and personalized treatment of spastic cerebral palsy based on the classification of spastic cerebral palsy were summarized and analyzed.ResultsThe common classification of spastic cerebral palsy are gross motor function classification system (GMFCS) and manual ability classification system (MACS). The surgical methods of spastic cerebral palsy can be divided into soft tissue surgery, nerve surgery, and bone and joint surgery. The precise diagnosis of spastic cerebral palsy includes qualitative diagnosis, localization diagnosis, and quantitative diagnosis. Based on precise diagnosis and classification, one or more corresponding surgical methods are selected for treatment.ConclusionThe manifestations of spastic cerebral palsy are so diverse that it is necessary to select rational surgeries based on precise diagnosis to achieve individualized treatment.

    Release date:2019-12-23 09:44 Export PDF Favorites Scan
  • Progress on the application of tranexamic acid in adolescent spine corrective surgery

    ObjectiveTo review the advances in the application of tranexamic acid (TXA) in adolescent spinal corrective surgery.MethodsThe mechanism of action and pharmacokinetic, effectiveness, dosage, safety as well as methods of administration were comprehensively summarized by consulting domestic and overseas related literature about the application of TXA in adolescent spinal corrective surgery in recent years.ResultsTXA efficaciously reduce intraoperative blood loss, transfusion rate and volume, postoperative drainage volume in adolescent spinal corrective surgery. At present, the most common method of administration in adolescent spinal corrective surgery is that a loading dose is given intravenously before skin incision or induction of anesthesia, followed by a maintenance dose until the end of the surgery. The range of loading dose and maintenance dose is 10-100 mg/kg and 1-10 mg/(kg·h), respectively. No drug related adverse event has been reported in this range.ConclusionThe effectiveness and safety of TXA in adolescent spinal surgery have been basically confirmed. However, further studies are needed to determine the optimal dosage, method of administration as well as whether it could reduce blood loss after surgery.

    Release date:2020-11-27 06:47 Export PDF Favorites Scan
  • Relationship between O-EA angle and lower cervical curvature in patients with anterior atlantoaxial dislocation before and after occipitocervical fusion

    ObjectiveTo investigate the relationship between O-EA angle and lower cervical curvature in patients with anterior atlantoaxial dislocation undergoing occipitocervical fusion, and to analyze the effect of O-EA angle on lower cervical curvature.MethodsThe clinical data of 61 patients with anterior atlantoaxial dislocation undergoing occipitocervical fusion who were admitted between April 2010 and July 2018 and met the selection criteria were retrospectively analyzed. There were 32 males and 29 females, with an age of 14-76 years (mean, 50.7 years). The fixed segment included 19 cases of C0-C2, 27 cases of C0-C3, 14 cases of C0-C4, and 1 case of C0-C5. The O-EA angle, C2-7 Cobb angle, and T1 tilt angle were measured before operation and at last follow-up. According to the O-EA angle measured at last follow-up, the patients were divided into <95° group (group A), 95°-105° group (group B), and >105° group (group C), and compared the differences of gender, age, fixed segment (short segment was at C3 and above, long segment was beyond C3), and C2-7 Cobb angle. Correlation analysis between the O-EA angle and C2-7 Cobb angle before operation and at last follow-up, as well as the changes of O-EA angle and C2-7 Cobb angle between before operation and at last follow-up were analyzed.ResultsAll 61 patients were followed up 12-24 months, with an average of 22.4 months. There was no significant difference in O-EA angle, C2-7 Cobb angle, and T1 tilt angle before operation and at last follow-up (P>0.05). According to the last follow-up O-EA angle grouping, there were 14 cases in group A, 29 cases in group B, and 18 cases in group C. There was no significant difference in age, gender composition, and fixed segment composition among the three groups (P>0.05); the differences in C2-7 Cobb angles among the three groups were significant (P<0.05), groups A, B, and C showed a gradually increasing trend. The O-EA angle was positively correlated with C2-7 Cobb angle before operation and at last follow-up (r=0.572, P=0.000; r=0.618, P=0.000); O-EA angle change at last follow-up was also positively correlated with C2-7 Cobb change (r=0.446, P=0.000).ConclusionThe O-EA angle of patients with anterior atlantoaxial dislocation is positively correlated with C2-7 Cobb angle. Too large O-EA angle should be avoided during occipitocervical fixation, otherwise it may accelerate the degeneration of the lower cervical spine.

    Release date:2021-04-27 09:12 Export PDF Favorites Scan
  • Establishment of micro-vessels model of cross-boundary perforator flap in rat via digital technology

    Objective To investigate the feasibility and application value of digital technology in establishing the micro-vessels model of cross-boundary perforator flap in rat. Methods Twenty 8-week-old female Sprague Dawley rats, weighing 280-300 g, were used to established micro-vessels model. The cross-boundary perforator flaps of 10 cm×3 cm in size were prepared at the dorsum of 20 rats; then the flaps were suturedin situ. Ten rats were randomly picked up at 3 and 7 days after operation in order to observe the necrosis of flap and measure the percentage of flap necrosis area; the lead-oxide gelatin solution was used for vessels perfusion; flaps were harvested and three-dimensional reconstruction of micro-vessel was performed after micro-CT scanning. Vascular volume and total length were measured via Matlable 7.0 software. Results The percentage of flap necrosis area at 3 days after operation was 19.08%±3.64%, which was significantly lower than that at 7 days (39.76%±3.76%;t=10.361, P=0.029). Three-dimensional reconstruction via the micro-CT clearly showed the morphological alteration of micro-vessel of the flap. At 3 days after operation, the vascular volume of the flap was (1 240.23±89.71) mm3 and the total length was (245.94±29.38) mm. At 7 days after operation, the vascular volume of the flap was (1 036.96±88.97) mm3 and the total length was (143.20±30.28) mm. There were significant differences in the vascular volume and the total length between different time points (t=5.088, P=0.000; t=7.701, P=0.000). Conclusion The digital technology can be applied to visually observe and objectively evaluate the morphological alteration of the micro-vessels of the flap, and provide technical support for the study of vascular model of flap.

    Release date:2017-12-11 12:15 Export PDF Favorites Scan
  • Comparative study on biological characteristics between different generations of rabbit nucleus pulposus cells

    ObjectiveTo research the biological characteristics of different generations of rabbit nucleus pulposus cells (NPCs) that were cultured with natural culture and subculture method.MethodsThe thoracolumbar segments of New Zealand white rabbits (6-8 weeks old and weighing 1.5-2.5 kg) were obtained and nucleus pulposus were isolated from disc regions. And NPCs were harvested by enzymatic digestion from nucleus pulposus. Primary NPCs were counted as P0 generation. Then, NPCs were passaged by trypsin and counted as P1, P2, P3 with a totle of 4 generations. P0 to P3 generations NPCs were separately examined by observation of cell morphology and proliferation time, detection of apoptosis rates of cells by flow cytometry, and detection of hypoxia-inducible factor 1α (HIF-1α), matrix metalloproteinases 2 (MMP-2), Aggrecan, and collagen type Ⅱ proteins by immunofluorescence and Western blot.ResultsThe morphology of NPCs transformed from triangular or polygonal in P0 generation to spindle in P3 generation; the characteristic vacuolated cells gradually disappeared; and the cell volume and cell proliferation time increased. The cell apoptosis rates were 5.47%±0.91%, 13.77%±2.42%, 33.46%±1.82%, and 38.76%±1.50% from P0 to P3 generations, with the increase of culture time, and there were significant differences between 4 generations (P<0.05). Immunofluorescence staining showed that with the increase of cells generation, the fluorescence intensity of HIF-1α, collagen type Ⅱ, and Aggrecan decreased, and the fluorescence intensity of MMP-2 increased. Western blot results showed that the relative expression of HIF-1α protein was high in P0 generation, the P1 generation has a rising trend, and then gradually decreased; the differences between generations were significant (P<0.05). The relative expression of collagen type Ⅱ protein decreased from P0 to P3 generations and there were significant differences between generations (P<0.05). The relative expression of Aggrecan protein decreased from P0 to P2 generations and there were significant differences between generations (P<0.05); but no significant difference was found between P2 and P3 generations (P>0.05). The relative expression of MMP-2 protein increased significantly in P3 generation; except that the difference between P0 and P2 generations was not significant (P>0.05), the significant differences were found between the other generations (P<0.05).ConclusionRabbit NPCs degeneration model was successfully established by the natural culture and subculture method. Transforming of NPCs morphology, increasing of cell apoptosis rates, decreasing of anabolism, and increasing of catabolism were presented in NPCs degeneration model.

    Release date:2018-05-30 04:28 Export PDF Favorites Scan
  • Development and validation of a nomogram model for predicting knee function improvement in early postoperative period after total knee arthroplasty

    Objective To develop and validate a nomogram prediction model of early knee function improvement after total knee arthroplasty (TKA). Methods One hundred and sixty-eight patients who underwent TKA at Sichuan Province Orthopedic Hospital between January 2018 and February 2021 were prospectively selected to collect factors that might influence the improvement of knee function in the early postoperative period after TKA, and the improvement of knee function was assessed using the Knee Score Scale of the Hospital for Special Surgery (HSS) at 6 months postoperatively. The patients were divided into two groups according to the postoperative knee function improvement. The preoperative, intraoperative and postoperative factors were compared between the two groups; multiple logistic regression was performed after the potential factors screened by LASSO regression; then, a nomogram predictive model was established by R 4.1.3 language and was validated internally. Results All patients were followed up at 6 months postoperatively, and the mean HSS score of the patients increased from 55.19±8.92 preoperatively to 89.27±6.18 at 6 months postoperatively (t=−40.706, P<0.001). LASSO regression screened eight influencing factors as potential factors, with which the results of multiple logistic regression analysis showed that preoperative body mass index, etiology, preoperative joint mobility, preoperative HSS scores, postoperative lower limb force line, and postoperative analgesia were independent influencing factors for the improvement of knee function in the early postoperative period after TKA (P<0.05). A nomogram model was established based on the multiple logistic regression results, and the calibration curve showed that the prediction curve basically fitted the standard curve; the receiver operating characteristic curve showed that the area under the curve of the nomogram model for the prediction of suboptimal knee function in the early postoperative period after TKA was 0.894 [95% confidence interval (0.825, 0.963)]. Conclusions There is a significant improvement in knee function in patients after TKA, and the improvement of knee function in the early postoperative period after TKA is influenced by preoperative body mass index, etiology, and preoperative joint mobility, etc. The nomogram model established accordingly can be used to predict the improvement of knee function in the early postoperative period after TKA with a high degree of differentiation and accuracy.

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