Objectives:To investigate the incidence,relative risk factors and treatment strategies of rod breakage after correction and internal fixation of adult spinal deformity(ASD).Methods:The clinical data of ASD patients treated with posterior corrective operation and internal fixation in the Department of Orthopedics of Xinqiao Hospital between January 2015 and December 2019 were analyzed retrospectively.A total of 79 patients aged 45-75 years(62.1±7.7 years)were included.The follow-up period was 24-59 months(30.6±9.2 months).According to whether the rod was broken during the follow-up period,the patients were divided into rod fracture group(RF group)and rod non-fracture group(NRF group).The sex,age,body mass index(BMI),bone mineral density(BMD)T value,complications and follow-up time of the two groups were recorded.The sagittal vertical axis(SVA),pelvic incidence(PI),pelvic tilt(PT),sacral slope(SS),thoracic kyphosis(TK),lumbar lordosis(LL),LL-TK value,PI-LL value,and coronal Cobb angle were measured before and after operation.The operation-related information of the two groups was collected,including operative time,intraoperative blood loss,the number of fixed fusion segments,whether three-column osteotomy,whether the lower fixed ver-tebrae involved the sacrum or pelvis,and whether there was interbody fusion.The position,time and revision operation of the broken rod in the RF group were recorded.The data of the two groups were compared and analyzed by Spearman test,and the positive parameters were further analyzed by multivariate logistic regres-sion to find potential risk factors for rod fractures.Odds ratio(OR)and 95％confidence interval(CI)were cal-culated.Results:Among the 79 patients,rod fracture occurred in 14 patients(17.7％),with bilateral fracture in 11 cases and unilateral fractures in 3 cases.The time of rod fracture occurred at 6-31 months after oper-ation(averaged 16 months),which occurred at the early stage after operation(within 24 months)in 10 patients(71.4％)and at 24 months after operation in 4 patients(28.6％).The rod fracture occurred at the osteotomy site in 11 cases and at T10-12 level in 3 cases.Spearman test showed that younger age(P=0.038),more lev-els of fusion(P＜0.001),3-column osteotomy(P＜0.001)and bigger preoperative SV A(P＜0.00 1)were correlated with rod breakage.Multivariate logistic regression analysis showed that more levels of fusion(P=0.037,OR=2.043,95％CI=1.046-3.992),3-column osteotomy(P=0.044,OR=0.113,95％CI=0.014-0.941),and bigger preop-erative SVA(P=0.006,OR=1.1 19,95％CI=1.032-1.212)were the risk factors of rod breakage after corrective surgery for ASD patients.11 patients(78.6％)underwent revision surgery because of intractable low back pain or progression of spinal deformities,and were replaced the broken rods through posterior primary incision ap-proach,combined with satellite rod technique;And meanwhile,out of which,5 patients underwent one-stage retroperitoneal approach for anterior iliac bone graft fusion and received satisfactory results during follow-up.Conclusions:The incidence of rod breakage after correction and internal fixation in ASD patients is high.More levels of fusion,3-column osteotomy,and greater preoperative SVA were significantly associated with rod fracture.The"Multi-rod technique"and anterior bone graft fusion technique can be used in the revision operation of rod fracture.

Objective To investigate the pathological changes of spinal cord tissues after spinal cord injury and their significance for clinical diagnosis and treatment of complete spinal cord injury.Methods Patients with complete spinal cord injury were selected.Mter rigorous ethical review and patient informed consent,damaged section of the spinal cord and necrotic tissue were removed and transplanted with the function biological material with autologous stem cell.The specimen of injured spinal cord collected during the operation were divided into three phases according to injury time:3 cases of acute phase (≤ 3 days),3 cases of subacute phase (4-14 days),and 1 case of chronic phase (＞ 14 days).The pathological changes of injured spinal cord tissue were observed through HE staining,and the expression of hypoxia inducible factor 1α (HIF-1α),tumor necrosis factor (TNF-α),microtubule-associated protein(MAP2) were detected by immunofluorescence.Results (1) HE staining showed that the acute injury mainly manifested as diffuse hyperemia and liquefaction,subacute injury infiltration of inflammatory cells and spinal cord liquefaction,and chronic injury mainly scar repair.(2)The fluorescence intensity (24.67 ±0.51) of HIF-1o in chronic injury was higher than acute (3.17 ± 0.40) and subacute injury (4.62 ± 0.48) (P ＜ 0.05),and the fluorescence intensity of subacute injury was higher than that of acute injury (P ＜ 0.05).(3) The fluorescence intensity (17.60 ± 1.17) of TNF-α in subacute injury was higher than that of acute injury (5.35 ± 0.33) and chronic injury (1.81 ± 0.17) (P ＜0.05);(4) The fluorescence intensity of MAP2 was 9.46 ±0.41 in acute injury,higher than 3.25 ± 0.42 in subacute injury and 1.16 ± 0.08 in chronic injury (P ＜ 0.05).Conclusions There are hypoxia,inflammation,neuronal apoptosis and repair in the spinal cord tissues after complete spinal cord injury,such as hyperemia,liquefaction,necrosis and gradual scar repair.The severity of inflammation and hypoxia significantly differs among different injury phases.The inflarmnatory cytokines are mainly active in the microenvironment during subacute injury.Hypoxia is mainly involved in the pathological changes of chronic injury.This can provide a new theoretical basis for the clinical treatment of complete spinal cord injury and the timing of surgical treatment.

Objective:To explore the reoperation rate and risk factors of adjacent segment disease (ASDis) in patients with lumbar degenerative diseases after transforaminal lumbar interbody fusion (TLIF).Methods:The clinical data of 460 patients who underwent TLIF for lumbar degenerative diseases in our hospital from January 2011 to December 2013 were retrospectively analyzed. There were 204 males and 256 females with an age of 54.6±12.6 years (range, 20-85 years). Divided into ASDis group and None ASDis (N-ASDis) group according to the occurrence of ASDis and received surgical treatment. The age of ASDis group was 57.9±12.2 years, with 14 males and 12 females, while the age of N-ASDis group was 54.4±12.5 years, with 188 males and 246 females. Count the reoperation rate of ASDis. Compare the age, body mass index (BMI), comorbidities, surgery-related parameters, length of stay, imaging parameters before and after surgery between the two groups, and use univariate analysis and logistic regression analysis to explore risk factors for ASDis.Results:Among 460 patients who underwent TLIF due to lumbar degenerative diseases, 26 patients developed ASDis and received surgical treatment, the reoperation rate was about 5.7%. Among them, the reoperation rate of ASDis with above Pfirrmann grade III in the adjacent intervertebral disc was about 53.1% (17/32). The average onset time of adjacent segment disease was 76.3±25.0 months (range, 30-111 months). Univariate analysis showed that BMI ( t=3.86, P<0.001), history of hypertension (χ 2=5.30, P=0.021), preoperative adjacent vertebral disc degeneration (χ 2=85.90, P<0.001), preoperative adjacent spinal canal stenosis (χ 2=25.35, P<0.001), and preoperative intervertebral space height of adjacent segments ( t=4.33, P<0.001) were statistically different among patients with or without ASDis. Incorporating the above indicators into the logistic regression model, the analysis results showed that body mass index (BMI) >24.9 kg/m 2 and preoperative adjacent intervertebral disc degeneration ≥III degree were risk factors for ASDis after TLIF. Conclusion:The reoperation rate of ASDis after TLIF in patients with lumbar degenerative disease is about 5.7%. BMI>24.9 kg/m 2 and preoperative adjacent intervertebral disc degeneration ≥III degree are risk factors for ASDis and received surgical treatment after TLIF.

Objective:To investigate the feasibility and clinical outcome of single-stage posterior total en bloc spondylectomy via posterior approach for lowerlumbar spinal malignant tumors.Methods:The clinical data of 23 patients with metastatic tumors of the lower lumbar spine who underwent single-stage posterior total En bloc spondylectomy in our hospital from January 2012 to June 2018 were analyzed retrospectively. There were 14 males and 9 females, age 57.9±10.8 years old (range, 37-74 years old). All patients were treated with single-stage posterior total en blocspondylectomy, titanium mesh implantation and posterior pedicle screw fixation. Observation items included operation time, intraoperative blood loss, postoperativehospital stays,the visual analogue scale (VAS) and the Eastern Cooperative Oncology Group (ECOG) physical condition score of the patients before operation,1 month after operationand 6 months after operation, the American spinal injury association (ASIA) spinal cord injury grade pre-operation andpostoperation, perioperative complications, local recurrence and survival state.Results:The median fellow-up time of this group was 20 months (range 6-56 months). At the end of the last follow-up, there were 3 patients who survived, the average follow-up time of the three patients who survived to the last follow-up was 37.3±11.7 months. One of them had local recurrence, but survived with tumor. The operative time was 155-510 min, with an average of 258±96 min, the intraoperative blood loss was 750-2 500 ml, with an average of 1 258.7±528.6 ml, and the postoperative hospital stay was 10-30 d, with an average of 18.4±4.6 d. VAS score decreased from 7.4±0.8 before operation to 2.6±0.6 1 month after operation, and ECOG score decreased from 1.6±0.9 before operation to 0.9±0.76 months after operation, showing statistically significant differences ( P<0.05). 6 patients presented with postoperative acute nerve root stimulation, 3 patients presented with postoperative cerebrospinal fluid leakage, 3 patients presented with postoperative surgical site infection, 1 with pulmonary infection, and 3 patients presented with titanium mesh displacement. Conclusion:Single-stage posterior total En bloc spondylectomy is feasible for the treatment of metastatic tumors of the lower lumbar spine. Although the operation is quite challenging due to its special anatomical structure and biomechanical characteristics,the long-term follow-up effect is satisfactory.

Metabolic reprogramming is a hallmark of cancer, including lung cancer. However, the exact underlying mechanism and therapeutic potential are largely unknown. Here we report that protein arginine methyltransferase 6 (PRMT6) is highly expressed in lung cancer and is required for cell metabolism, tumorigenicity, and cisplatin response of lung cancer. PRMT6 regulated the oxidative pentose phosphate pathway (PPP) flux and glycolysis pathway in human lung cancer by increasing the activity of 6-phospho-gluconate dehydrogenase (6PGD) and α-enolase (ENO1). Furthermore, PRMT6 methylated R324 of 6PGD to enhancing its activity; while methylation at R9 and R372 of ENO1 promotes formation of active ENO1 dimers and 2-phosphoglycerate (2-PG) binding to ENO1, respectively. Lastly, targeting PRMT6 blocked the oxidative PPP flux, glycolysis pathway, and tumor growth, as well as enhanced the anti-tumor effects of cisplatin in lung cancer. Together, this study demonstrates that PRMT6 acts as a post-translational modification (PTM) regulator of glucose metabolism, which leads to the pathogenesis of lung cancer. It was proven that the PRMT6-6PGD/ENO1 regulatory axis is an important determinant of carcinogenesis and may become a promising cancer therapeutic strategy.