1.Biomechanical properties of a novel automatic anti-rotation posterior atlantoaxial internal fixation system: a finite element analysis
Min YANG ; Xiangyang MA ; Jincheng YANG ; Shujin CHEN ; Xiaobao ZOU
Chinese Journal of Tissue Engineering Research 2017;21(19):3031-3037
BACKGROUND: Atlantoaxial posterior approach is currently the main surgical treatment for atlantoaxial instability and/or dislocation, but the shape of rod in normal screw-rod device system is cylindrical. To obtain satisfactory reduction of atlantoaxis, the rod will be pre-bent obviously before fixation; however, the cylindrical rod will be rotated when tighten the nuts. Extra devices will be required to adjust and maintain the direction of the rod, thereafter, the surgical field will be blocked by the device, and spinal injury will occur once the devices are not held tightly. While the novel automatic anti-rotation rod has the function of anti-rotation during nut-tightening process, and also holds all the advantages of normal rod. Further research should be performed for the differences in biomechanical characteristics between two methods.OBJECTIVE: To investigate the biomechanical properties of the novel automatic anti-rotation rod for internal fixation system of atlantoaxial posterior approach based on three-dimensional finite-analysis model of upper cervical spine.METHODS: The three-dimensional finite element model of upper cervical spine with internal rod fixation system was developed. The biomechanical characteristics of the internal fixation system were analyzed. RESULTS AND CONCLUSION: The traditional and novel three-dimensional finite element model with realistic and geometric similarity contained 198330 elements, 964747 nodes and 246788 elements, 996069 nodes,correspondingly. There was no obvious stress concentration in both two systems, stress was concentrated mainly in the screw-bone and screw-rod interfaces. The stress values of the novel system were higher than those of the traditional system, but the maximum Von Misses Stress of two systems was lower than the yield (795-827 MPa ) and ultimate (860-896 MPa) strength of titanium alloys. These results show that the design of the novel automatic anti-rotation rod-screw fixation system has matched the biomechanical requirements for new internal fixation instruments, and is one safe, effective and practical device for atlantoaxial posterior procedure showing promising application prospect.
2.Effects of intravenous infusion of lidocaine on colorectal resection
Yiqing ZOU ; Haigui NIE ; Bin WEI ; Shuzhen ZENG ; Xiaobao LI ; Zhixing YANG
Chinese Journal of Postgraduates of Medicine 2010;33(6):31-33
Objective To investigate the effects of intravenous infusion of lidocaine on colorectal resection.Methods Sixty patients undergoing colorectsl resection were randomly divided into group L [receiving intravenous infusion of 1%lidocaine,bolus injection of 1.5 mg/kg lldocaine at induction of anesthesia,followed by a continuous infusion of 1.5 mg/(kg·h)intraoperatively and for 12 h postoperatively]and group C(an equal volume of saline).Postoperative pain scores(VAS score)and morphine consumption were measured.Times of flatus and first defecation were recorded.Results The end expiration sevotturane concentration maintaining hemedynamics stable in group L was lower than that in group C(P<0.05).The dose of sulfentsnyl was(17.5±3.8)μg in group L,(25.6±4.5)μg in group C,there was significant difference between two groups(P<0.05).The times of flatus first,defecation and morphine conaumption at 24 and 48 h after operation in group L were lower than those in group C[(23±6)h vs(28±7)h,(31±7)h vs(43±9)h,(32±6)mg vs(46±8)nag and(58±7)mg vs(71±10)mg,P<0.05].There was no significant difference at resting VAS score,but there was significant difference at movement and cough VAS score between twp groups(P<0.05).Conclusion Perioperative administration of low doses of intravenous infusion of lidocaine reduces intraoperative anesthetic requirements and has a clinically relevant beneficial effect on postoperative recovery after colorectal resection.
3.Biomechanical analysis of new horizontal screw-screw crosslink in C1-C2 pedicle screw-rod fixation
Beiping OUYANG ; Xiangyang MA ; Chunshan LUO ; Xiaobao ZOU ; Tingsheng LU ; Qiling CHEN
Chinese Journal of Tissue Engineering Research 2024;28(12):1837-1841
BACKGROUND:Posterior atlantoaxial pedicle screw rod internal fixation is the main method for treating atlantoaxial dislocation,and the horizontal crosslink plays an important role in the antirotation ability of the internal fixation system.The new horizontal screw-screw crosslink can effectively overcome the disadvantages of traditional horizontal crosslink,such as inconvenient installation,impact on bone grafting bed,and potential spinal cord injury.However,the biomechanical properties of the new horizontal screw-screw crosslink with different installation modes are still unclear. OBJECTIVE:To investigate the biomechanical characteristics of new different installation modes of horizontal screw-screw crosslink in the C1-C2 pedicle screw-rod fixation and to provide a theoretical basis for optimal installation mode. METHODS:Six fresh human occipitocervical specimens were divided into the intact state group(group A),and the atlantoaxial instability model of type Ⅱ odontoid fracture was established based on the intact state group as the instability group(group B).The C1-C2 pedicle screw-rod fixation was performed on each specimen based on the instability group(group C).In group C,different installation modes of horizontal screw-screw crosslink were successively installed in each specimen,including upper transverse connection(two atlas screw tails)as group D,lower transverse connection(two axis screw tails)as group E,diagonal transverse connection(upper left and lower right for group F,lower left and upper right for group G),and cross transverse connection as group H.The specimen models were tested in order of flexion,extension,lateral flexion and lateral rotation on a three-dimensional motion machine,and the atlantoaxial range of motion of each group of specimens was obtained.Repeated measure analysis of variance was used to evaluate the biomechanical properties of each group. RESULTS AND CONCLUSION:(1)Under six states,the range of motion of groups A,C,D,E,F,G and H was smaller than that of group B,and there were statistically significant differences(P<0.05).(2)In the flexion and extension states,there was no significant difference among the five types of horizontal screw-screw crosslink groups(P>0.05).(3)In the left and right rotation directions,there were significant differences in D and E groups compared with F,G and H groups(P<0.05);there were no significant differences between D and E groups,and F and G groups(P>0.05),and there were no significant differences in F and G groups compared with H group(P>0.05).(4)In conclusion,under flexion-extension states,the biomechanical stability of five types of horizontal screw-screw crosslink groups was similar,but under the rotation state,the stability of diagonal horizontal screw-screw crosslink group and cross horizontal screw-screw crosslink group was obviously better than that of transverse horizontal screw-screw crosslink group;however,the stability of diagonal horizontal screw-screw crosslink group is similar to the cross horizontal screw-screw crosslink group,so the former is more worthy of clinical recommendation.
4.Three-dimensional finite element analysis of a new horizontal screw-screw crosslink in posterior atlantoaxial internal fixation
Beiping OUYANG ; Xiangyang MA ; Chunshan LUO ; Xiaobao ZOU ; Tingsheng LU ; Qiling CHEN
Chinese Journal of Tissue Engineering Research 2024;28(9):1320-1324
BACKGROUND:The addition of traditional rod-rod fixation for atlantoaxial joint disease to C1-C2 pedicle screw-rod fixation(C1-C2 PSR)can provide stronger anti-rotation stability for screw/rod fixation,but there is a risk of installation difficulties,impact on bone graft bed,and spinal cord injury.The new horizontal screw-screw crosslink(hS-S CL)designed by the authors can effectively overcome the above shortcomings,but its biomechanical properties are unclear. OBJECTIVE:To analyze biomechanical properties of new horizontal screw-screw crosslink in C1-C2 PSR by three-dimensional finite element analysis. METHODS:CT thin layer scanning data were collected from the occipital base to the axis(C0-2)of one adult healthy male volunteer.The atlantoaxial finite element models were established respectively:the normal group,the unstable group,the non-crosslink group(unstable+C1-C2 PSR),and the crosslink group(C1-C2 PSR+hS-S CL).Range of motion and Von Miss Stresses in flexion and extension,lateral flexion and rotation of the four groups were calculated by applying 1.5 Nm torque to each finite element model,and the stress cloud was extracted. RESULTS AND CONCLUSION:(1)Range of motion of the unstable group was increased by 43.8%-78.7%compared with the normal group,and the range of motion of the internal fixation groups was 90.2%-98.7%lower than that of the unstable group under six conditions.The range of motion of the crosslink group and the non-crosslink group was basically the same in flexion and extension states,but in lateral flexion and rotation states,the range of motion of the crosslink group decreased 34.3%-43.8%and 78.6%-79.1%,respectively,compared with the non-crosslink group,and range of motion decreased most obviously in rotation state.(2)The stress peak of the internal plant model:The maximum stress of the crosslink group was generally smaller than that of the non-crosslink group,and the stress peak value of all the internal fixation groups was the lowest when the extension was carried out.(3)The stress cloud of internal plants showed that there was no obvious stress concentration phenomenon in the internal fixation,and the main stress distribution areas were the screw root and bone joint,and the crosslink ends were the screw tail groove or the joint rod joint.(4)The new horizontal screw-screw crosslink can obviously improve the anti-rotation stability of internal fixation and it can share part of the pressure in the three-dimensional motion direction of the internal fixation system and reduce the maximum stress of the internal plants.However,the stress distribution is obvious at both ends of the crosslink,and this part may be prone to fracture of the crosslink.
5.Subclassification and clinical treatment options of refractory atlantoaxial dislocation
Xiangyang MA ; Jincheng YANG ; Xiaobao ZOU ; Binbin WANG ; Haozhi YANG ; Su GE ; Yuyue CHEN ; Hong XIA
Chinese Journal of Orthopaedics 2023;43(7):411-421
Objective:To subdivide clinical classification of refractory atlantoaxial dislocation, and evaluate the reliability of new subdivide clinical classification of refractory atlantoaxial dislocation.Methods:From January 2010 to December 2018, 48 patients with refractory atlantoaxial dislocation were treated, including 19 males and 29 females, aged 16 to 65 years, with an average of 39.2±13.3 years. According to the changes of relative anatomical position of C 1 and C 2 under general anesthesia with heavy traction of 1/6 body weight, subdivide clinical classification of refractory atlantoaxial dislocation were proposed, and refractory atlantoaxial dislocation was divided into traction loosening type (atlantoaxial angle≥5°) and traction stabilization type (atlantoaxial angle<5°). The traction loosening type was directly reduced by posterior atlantoaxial screw-rod fixation and fusion without anterior or posterior soft tissue release. For traction stabilization type, transoral soft tissue release was performed first, and then transoral anterior reduction plate fixation and fusion or posterior atlantoaxial screw-rod fixation and fusion were performed. Atlantodental interval (ADI) and atlantoaxial angle (AAA) were measured and collected before and after surgery to evaluate atlantoaxial reduction. The space available for the spinal cord (SAC) were measured to evaluate spinal cord compression. Visual analogue score (VAS) was used to evaluate the neck pain levels, and Japanese Orthopaedic Association (JOA) scores was used to evaluate the neurological function. American Spinal Cord Injury Association impairment scale (AIS) was used to evaluate the degree of spinal cord injury. One week, 3, 6, 12 months postoperatively and the annual review of the X-ray and CT scan were checked, in order to evaluate the reduction, internal fixation and bone graft fusion. Results:Among all 48 cases, 22 cases were traction loosening type, of which posterior atlantoaxial screw-rod fixation and fusion were performed in 16 cases and occipitocervical fixation and fusion in 6 cases. 26 cases were traction stabilization type, and they all underwent anterior transoral release, and then, anterior TARP fixation and fusion were performed in 24 cases and posterior screw-rod fixation and fusion in the other 2 cases. X-ray, CT and MRI images and of all patients 1 week after surgery showed good atlantoaxial reduction and decompression of spinal cord. In each of the two types, there was one case lost to follow-up. For 46 cases in follow-up, the follow-up time ranged from 6 to 72 months, with an average of 38.0±17.2 months. Among 46 cases, 21 cases of traction loosening type showed that, ADI reduced from preoperative 9.9±2.2 mm to 2.3±0.9 mm at 3 months after surgery and 2.3±1.0 mm at the last follow-up, AAA increased from preoperative 57.9°±12.3° to 91.0°±2.2° at 3 months after surgery and 90.9°±2.2° at the last follow-up, SAC increased from preoperative 9.8±1.3 mm to 15.1±0.7 mm at 3 months after surgery and 14.9±0.7 mm at the last follow-up, VAS score reduced from preoperative 1.5±2.1 to 0.7±1.0 at 3 months after surgery and 0.3±0.6 at the last follow-up, and JOA score increased from preoperative 10.2±1.7 to 13.3±1.3 at 3 months after surgery and 14.9±1.5 at the last follow-up. Twenty-five cases of traction stabilization type presented that, ADI reduced from preoperative 9.7±2.0 mm to 2.1±1.4 mm at 3 months after surgery and 2.1±1.3 mm at the last follow-up, AAA increased from preoperative 55.8°±9.2° to 90.9°±1.4° at 3 months after surgery and 90.9°±1.3° at the last follow-up, SAC increased from preoperative 10.5±1.0 mm to 15.4±0.5 mm at 3 months after surgery and 14.8±2.8 mm at the last follow-up, VAS score reduced from preoperative 1.7±2.1 to 0.7±0.9 at 3 months after surgery and 0.3±0.5 at the last follow-up, and JOA score increased from preoperative 10.1±1.3 to 12.9±1.5 at 3 months after surgery and 14.4±1.3 at the last follow-up. In the traction loosening type, all the 10 grade D patients were improved to grade E at the last follow-up. In the 2 grade C patients of traction stabilization type before surgery, 1 patient was improved to grade E, 1 patient was improved to grade D, and all 11 patients with grade D were improved to grade E at the last follow-up. Bony fusion was obtained in all patients from 3 to 6 months, with an average of 4.4±1.5 months. During follow-up period, no looseness of internal fixation or redislocation happened.Conclusion:Refractory atlantoaxial dislocation can be divided into traction loosening type and traction stabilization type. For traction loosening type, satisfactory reduction can be achieved by using posterior atlantoaxial screw-rod system without soft tissue release. For traction stabilization type, anterior release is preferable, and then anterior TARP or posterior screw-rod can be used to achieve satisfactory reduction.
6.Posterior screw-rod fixation fusion for the treatment of atlantoaxial dislocation due to rheumatoid arthritis
Xiangyang MA ; Xiaobao ZOU ; Jincheng YANG ; Binbin WANG ; Haozhi YANG ; Hong XIA ; Zenghui WU ; Qingshui YIN
Chinese Journal of Orthopaedics 2017;37(24):1505-1510
Objective To investigate the clinical effect of posterior screw-rod fixation fusion for the treatment of atlantoaxial dislocation due to rheumatoid arthritis.Methods From January 2011 to December 2015,15 patients with atlantoaxial dislocation due to rheumatoid arthritis were treated,including 6 males and 9 females,aged 35 to 75 years (mean 55 years).All cases were evaluated about the difficulty of relocation by extension-flexion X-ray and treated with posterior screw-rod reduction,fixation and autogenous bone grafting under general anesthesia.Atlantodental interval (ADI) was measured and collected before and after surgery.Visual Analogue Scale/Score (VAS),American Spinal Cord Injury Association (ASIA) and Japanese Orthopaedic Association (JOA) scores were comprehensively used to evaluate the clinical effect.1 week,3,6,12 months postoperatively and the annual review of the X-ray and CT were checked,in order to evaluate the reduction,internal fixation and bone graft fusion.Results All patients were reducible dislocation and successfully performed the posterior screw-rod fixation fusion surgery.The patients were followed up for 3 to 24 months (average,15 months).Atlantoaxial solid bony fusion was obtained from 3 to 6 months.ADI reduced from preoperative 6.3±1.7 mm to postoperative 2.2±0.8 mm,VAS score reduced from preoperative 5.4±2.7 to postoperative 1.7±1.0,ASIA motor score improved from preoperative 82.3±15.6 to 95.3±4.5 at 6 months after the surgery,JOA score increased from preoperative 13.8±2.9 to 15.5±1.4 at 6 months after the surgery,and the statistical significance was revealed between preoperation and postoperation.Nine cases were in D grade of ASIA,3 cases improved from D to E grade after surgery,2 cases reached E grade in the other 6 cases after 6 months,2 cases recovered to E grade after 12 months and other 2 cases in D grade got uniformity after surgery.Well internal fixation and no redislocation were found on X-ray and CT during follow-up period.Conclusion Atlantoaxial dislocation because of rheumatoid arthritis was numerously reducible genre.Posterior screw-rod fixation and autogenous bone grafting can gain satisfying clinical efficacy.
7.Clinical significances of CD4/CD8 ratio and neutrophil-to-lymphocyte ratio in patients with multiple myeloma
Jingyun ZOU ; Yue LIU ; Yang CAO ; Guoqiang QIU ; Haoqing WU ; Zhilin WANG ; Xiaobao XIE
Journal of Leukemia & Lymphoma 2020;29(4):219-224
Objective:To investigate the clinical significances of CD4/CD8 ratio and neutrophil-to-lymphocyte ratio (NLR) in patients with multiple myeloma (MM).Methods:The clinical data of 124 MM patients in the Third Affiliated Hospital of Soochow University from December 2002 to April 2017 were retrospectively analyzed, and 31 healthy people were chosen as the controls. Peripheral blood T lymphocyte subsets were detected by using flow cytometry, and the correlations between CD4/CD8 ration and related clinical indicators were also investigated. All MM patients were divided into the high NLR group and the low NLR group according to the media of NLR, and the correlation of them with related clinical indicators, chromosome karyotype, overall survival (OS) and progression-free survival (PFS) was also compared.Results:Compared with the healthy control group, the proportion of CD4 + T cells [(35.28±6.58)% vs. (31.85±6.76)%, t = -2.067, P = 0.043], absolute value of NK cells [0.22×10 9/L (0.13×10 9/L-0.59×10 9/L) vs. 0.17×10 9/L (0.00×10 9/L-0.42×10 9/L), Z = -2.614, P = 0.009] and CD4/CD8 ratio [0.97 (0.50-2.69) vs. 0.81 (0.30-1.28), Z = -2.253, P = 0.024] was decreased, respectively. The proportion of CD8 + cells was increased [(36.93±7.38)% vs. (40.50±6.50)%, t = 2.074, P = 0.042] in MM group. The hemoglobin level of CD4/CD8 ratio ≥0.94 group was higher than that of CD4/CD8 ratio <0.94 [(98.89±21.35) g/L vs.(80.60±23.23) g/L, t = -2.066, P = 0.047]. Compared with the healthy control group, NLR was increased in MM group [1.54 (1.10-3.23) vs. 1.95 (0.29-12.70), Z = -2.384, P = 0.017]. Compared with the low NLR group (<1.95), serum β 2-microglobulin [4.56 mg/L (1.63-12.60 mg/L) vs. 6.17 mg/L (1.58-67.50 mg/L), Z = -2.586, P = 0.010] and serum creatinine [84.5 μmol/L (43.0-376.5 μmol/L) vs. 113.0 μmol/L (46.5-754.0 μmol/L), Z = -3.866, P < 0.001] was increased in the high NLR group for MM patients. The proportion of the male patients, β 2-microglobulin > 5.5 mg/L, serum creatinine > 177 μmol/L, stage Ⅲ of international staging system (ISS) in the high NLR group was higher than that in the low NLR group (all P < 0.05), and there was no statistically significant difference in the composition of chromosome karyotype (all P > 0.05). The median OS time in the low NLR group was longer than that in the high NLR group [30 months (20-40 months) vs. 17 months (7-27 months), χ 2 = 4.519, P = 0.034], and there was no statistically significant difference in the PFS of both groups ( P > 0.05). Multivariate Cox analysis demonstrated that the age, corrected serum calcium, serum creatinine, lactic dehydrogenase were the independent influencing factors of OS in MM (all P < 0.05), while NLR wasn′t an independent influencing factor of OS in MM ( P = 0.513). Conclusions:CD4/CD8 ratio is decreased and immune dysfunction occurs in MM patients. MM patients with high NLR have a shorter OS time.
8.Preliminary application of self-designed posterior reduction forceps for atlantoaxial dislocation in treatment of irreducible atlantoaxial dislocation
Xiangyang MA ; Xiaobao ZOU ; Haozhi YANG ; Shuang ZHANG ; Chenfu DENG ; Rencai MA ; Junlin CHEN ; Hong XIA
Chinese Journal of Orthopaedic Trauma 2023;25(10):853-858
Objective:To evaluate the preliminary clinical application of our self-designed posterior reduction forceps for atlantoaxial dislocation in the reduction and fixation of irreducible atlantoaxial dislocation with simple posterior screw-rod system.Methods:Our posterior reduction forceps was self-designed and developed to assist simple posterior screw-rod system in the treatment of irreducible atlantoaxial dislocation based on the posterior atlantoaxial screw-rod system. A retrospective study was conducted to analyze the clinical data of 5 patients with irreducible atlantoaxial dislocation who had been treated from January 2021 to October 2022 at Department of Spine Surgery, General Hospital of Southern Theatre Command of PLA with our self-designed posterior reduction forceps. There were 2 males and 3 females, aged 53, 62, 45, 32 and 48 years, respectively. Diagnosis: 1 case of free odontoid process combined with atlantoaxial dislocation, 2 cases of atlantoaxial dislocation, and 2 cases of old odontoid process fracture combined with atlantoaxial dislocation. Respectively, their preoperative Japanese Orthopaedic Association (JOA) scores were 9, 11, 12, 13 and 10 points and their atlanto-dental intervals (ADI) 9.8, 7.4, 6.6, 6.4 and 8.5 mm. Postoperatively, atlantoaxial reduction and spinal cord compression were evaluated by X-ray, CT, and MRI examinations, and internal fixation, atlanto-axial sequence, and bone graft fusion by X-ray and CT examinations. One week after surgery, the JOA scores were used to evaluate the patients' neurological function and the ADI was measured to evaluate the atlantoaxial reduction.Results:The surgery was successfully performed in the 5 patients, with no intraoperative complications like neurovascular injuries to the spinal cord. The postoperative atlantoaxial reduction was satisfactory, the position of internal fixation was good, the compression to the spinal cord was relieved, and the clinical symptoms were significantly improved. At 1 week after surgery, respectively, the JOA score: 13, 14, 14, 15 and 13; the ADI: 2.6, 2.1, 1.8, 1.5 and 2.2 mm; the follow-up time: 3, 6, 12, 9 and 6 months; the bone fusion time: 3, 3, 6, 6 and 3 months. Follow-ups revealed no loosening or fracture of internal fixation, good atlanto-axial sequence, and no recurrence of dislocation.Conclusion:Our self-designed posterior reduction forceps for atlantoaxial dislocation can assist the simple posterior screw-rod system to treat irreducible atlantoaxial dislocation, leading to good preliminary clinical outcomes.
9.Visual analysis of tyrosine kinase inhibitors in HER2 positive breast cancer
Jing ZOU ; Yaojuan CHU ; Qiuzheng DU ; Heying YUE ; Xiaobao WANG ; Shuzhang DU
China Pharmacy 2023;34(24):3036-3041
OBJECTIVE To analyze the research status, hotspot and development trend of tyrosine kinase inhibitors (TKIs) in the treatment of human epidermal growth factor receptor 2 (HER2) positive breast cancer. METHODS The literature related to TKIs in the treatment of HER2 positive breast cancer were searched from the Web of Science core collection database; the author, country/region, institution, subject field, journal and keywords was visualized by CiteSpace 6.1.R3 software. RESULTS A total of 732 pieces of literature were included, and the number of literature published showed an increasing trend year by year. The number of literature published in the United States was the largest (center degree 0.10), and the number of literature published in China ranked second (center degree 0.05). The most published and cited authors were Crown from St. Vincent’s University Hospital in Australia and Slamon from University of California, Los Angeles in the United States; the institution with the highest number of literature was the University of Texas MD Anderson Cancer Center, and the journal with the highest number of literature was the Journal of Clinical Oncology. The research mainly focused on five aspects: HER2 positive breast cancer treatment drugs, TKIs receptor, TKIs mechanism of action, HER2 positive breast cancer brain metastasis, and TKIs clinical trials. The main frontier areas and development trends were the combination of TKIs with other drugs or therapies to enhance targeting and reduce toxic side effects. CONCLUSIONS The study of TKIs in the treatment of HER2 positive breast cancer has attracted the attention of scholars at home and abroad. Chinese scholars and research teams need to strengthen cooperation and communication in the future, and cooperation with other countries should be strengthened in terms of the efficacy and safety of TKIs alone and combined with other drugs in the treatment of HER2 positive breast cancer.