Objective To explore the risk factors for noncontiguous spinal fractures(NSFs)in the elderly.Methods The clinical data of 614 elderly patients with spinal fracture from January 2013 to December 2019 were analyzed retrospectively.Patients were divided into the NSFs group and the Non-NSFs group according to whether NSFs occurred or not.Univariate analysis and multivariate Logistic regression analysis were used to screen the risk factors of NSFs.Results Univariate analysis showed that female(P=0.003),high-energy violent injury(P=0.032),osteoporosis(P=0.004),fracture in spring(P=0.020),and previous spinal fracture history(P<0.001)were associated with the occurrence of NSFs.Multivariate Logistic regression analysis showed that fracture in spring(P=0.024),previous spinal fracture history(P<0.001)and high-energy violent injury(P=0.038)were the independent risk factors for the occurrence of NSFs in the elderly.Conclusion High-energy violent injury,fracture in spring and previous spinal fracture history are the independent risk factors for the occurrence of NSFs in the elderly.Therefore,elderly patients with the above risk factors should be examined more carefully and comprehensively to avoid missed diagnosis and delayed diagnosis.In order to reduce the incidence of this disease,corresponding measures should be taken according to the preventable risk factors.

Objective To analyze the risk factors for increased drainage volume after open transforaminal lumbar interbody fusion(TLIF),and to establish a predictive model and then validate it.Methods The clinical data of 680 patients who underwent open TLIF at the General Hospital of Northern Theater Command from January 2016 to December 2019 were collected and the patients were randomly divided into the training group(n=476)and the validation group(n=204).Taking the predictive factors screened out by LASSO regression analysis as independent variables,a multivariate Logistic regression predictive model was constructed.The model was internally validated through the receiver operating characteristic(ROC)curve,Hosmer-Lemeshow goodness-of-fit test,and calibration curve,and its clinical utility was assessed via decision curve analysis(DCA).Results LASSO regression analysis screened out four predictive variables:age,number of surgical segments,operative duration,and intraoperative blood loss.The multivariate Logistic regression predictive model demonstrated that age≥60 years,number of surgical segments≥4,operative duration≥2 hours,and intraoperative blood loss≥200 mL were independent influencing factors for the increased postoperative drainage volume in patients undergoing TLIF(P<0.05).ROC curve analysis revealed an area under the curve(AUC)of 0.816(95%CI:0.798 to 0.867)in the training group and 0.783(95%CI:0.685 to 0.823)in the validation group,indicating that the predictive model had good discriminatory ability.Additionally,the Hosmer-Lemeshow goodness-of-fit test and calibration curve indicated that the predictive model had a good degree of fit,and the predicted probability was basically consistent with the actual probability,demonstrating a good calibration.The DCA results confirmed that this predictive model could be applied in clinical practice.Conclusion The risk factors for increased drainage volume after open TLIF include age,number of surgical segments,operative duration,and intraoperative blood loss.The predictive model established based on these factors demonstrates good performance,and it can be applied in clinical guidance for the selection of drainage tube removal time after TLIF.

Objective To analyze the risk factors for increased drainage volume after open transforaminal lumbar interbody fusion(TLIF),and to establish a predictive model and then validate it.Methods The clinical data of 680 patients who underwent open TLIF at the General Hospital of Northern Theater Command from January 2016 to December 2019 were collected and the patients were randomly divided into the training group(n=476)and the validation group(n=204).Taking the predictive factors screened out by LASSO regression analysis as independent variables,a multivariate Logistic regression predictive model was constructed.The model was internally validated through the receiver operating characteristic(ROC)curve,Hosmer-Lemeshow goodness-of-fit test,and calibration curve,and its clinical utility was assessed via decision curve analysis(DCA).Results LASSO regression analysis screened out four predictive variables:age,number of surgical segments,operative duration,and intraoperative blood loss.The multivariate Logistic regression predictive model demonstrated that age≥60 years,number of surgical segments≥4,operative duration≥2 hours,and intraoperative blood loss≥200 mL were independent influencing factors for the increased postoperative drainage volume in patients undergoing TLIF(P<0.05).ROC curve analysis revealed an area under the curve(AUC)of 0.816(95%CI:0.798 to 0.867)in the training group and 0.783(95%CI:0.685 to 0.823)in the validation group,indicating that the predictive model had good discriminatory ability.Additionally,the Hosmer-Lemeshow goodness-of-fit test and calibration curve indicated that the predictive model had a good degree of fit,and the predicted probability was basically consistent with the actual probability,demonstrating a good calibration.The DCA results confirmed that this predictive model could be applied in clinical practice.Conclusion The risk factors for increased drainage volume after open TLIF include age,number of surgical segments,operative duration,and intraoperative blood loss.The predictive model established based on these factors demonstrates good performance,and it can be applied in clinical guidance for the selection of drainage tube removal time after TLIF.

Objective To explore the risk factors for noncontiguous spinal fractures(NSFs)in the elderly.Methods The clinical data of 614 elderly patients with spinal fracture from January 2013 to December 2019 were analyzed retrospectively.Patients were divided into the NSFs group and the Non-NSFs group according to whether NSFs occurred or not.Univariate analysis and multivariate Logistic regression analysis were used to screen the risk factors of NSFs.Results Univariate analysis showed that female(P=0.003),high-energy violent injury(P=0.032),osteoporosis(P=0.004),fracture in spring(P=0.020),and previous spinal fracture history(P<0.001)were associated with the occurrence of NSFs.Multivariate Logistic regression analysis showed that fracture in spring(P=0.024),previous spinal fracture history(P<0.001)and high-energy violent injury(P=0.038)were the independent risk factors for the occurrence of NSFs in the elderly.Conclusion High-energy violent injury,fracture in spring and previous spinal fracture history are the independent risk factors for the occurrence of NSFs in the elderly.Therefore,elderly patients with the above risk factors should be examined more carefully and comprehensively to avoid missed diagnosis and delayed diagnosis.In order to reduce the incidence of this disease,corresponding measures should be taken according to the preventable risk factors.

Objective:To investigate and compare the clinical outcomes of the arterial pre-occlusion technique(APOT) and the traditional technique in the surgery of locally advanced pancreatic cancer with arterial involvement after conversion therapy.Methods:This is a retrospective cohort study. The clinical data of 145 patients with locally advanced pancreatic cancer with arterial involvement admitted to the Department of Hepato-Biliary-Pancreatic Surgery of the First Hospital Affiliated to Naval Medical University,from January 2020 to December 2022 were retrospectively analyzed. All patients completed neoadjuvant therapy for tumors, and the feasibility of radical surgical treatment was determined by a multidisciplinary collaborative team evaluation before surgery. According to whether the intraoperative artery was pre-occluded, 145 patients were divided into two groups, including 28 cases in the APOT group(16 males, 12 females, aged (59.0±9.4) years), and 117 cases in the routine surgery group(76 males, 41 females, aged (55.1±8.2) years). To ensure comparability of baseline data between the APOT group and the routine surgery group, a 1∶2 match was performed using the propensity score matching method, and the caliper value was 0.006 45. The t-test,the Mann-Whitney U test, χ2 test or Fisher′s exact test were used to compare the data between the two groups,respectively. Results:After matching the propensity score,there were 28 cases in the APOT group and 56 cases in the routine surgery group. There were no significant differences in gender,age,preoperative comorbidities,preoperative body mass index,surgical approaches,chemotherapy regimen,stereotactic body radiation therapy ratio,tumor markers,and type of invaded artery between the two groups (all P>0.05).The arterial occlusion time M(IQR) in the APOT group was 7.0(3.8)minutes(range:3 to 15 minutes),and no ischemic manifestations were observed in the distal target organs that blocked blood vessels after surgery. The operation time was (170.3±57.7)minutes in the APOT group and (235.0±80.2)minutes in the routine surgery group,and the difference was statistically significant ( t=-3.800, P<0.01). The APOT group also experienced less intraoperative blood loss(650(588)ml vs. 800(600)ml; U=1 026.500, P=0.021). No significant differences were found between the groups in combined vein resection and reconstruction,celiac trunk resection,early postoperative complications, readmission rates at 30 days,and postoperative length of stay(all P>0.05). Extra-arterial dissection was performed in all patients,with arterial resection and reconstruction in 3 cases: 2 cases in the APOT group(1 case involving the superior mesenteric artery and 1 case involving the common hepatic artery) and 1 case in the routine group(involving the common hepatic artery). Postoperative abdominal bleeding occurred in 4 cases,with 3 cases in the routine group,1 case in the routine group. The R0 resection rate was 85.7%(24/28) in the APOT group and 80.4%(45/56) in the routine group,without significant differences between the groups( P=0.763). The median overall survival time was 27.6 months for the APOT group and 22.5 months for the routine group,while the median disease-free survival was 11.7 months and 16.8 months,respectively,with no significant differences between the two groups( P=0.532, P=0.927). Conclusion:The arterial pre-occlusion technique can be used for extra-arterial dissection in patients with locally advanced pancreatic cancer involving the arteries,reducing surgery time and intraoperative blood loss.

Objective:To investigate and compare the clinical outcomes of the arterial pre-occlusion technique(APOT) and the traditional technique in the surgery of locally advanced pancreatic cancer with arterial involvement after conversion therapy.Methods:This is a retrospective cohort study. The clinical data of 145 patients with locally advanced pancreatic cancer with arterial involvement admitted to the Department of Hepato-Biliary-Pancreatic Surgery of the First Hospital Affiliated to Naval Medical University,from January 2020 to December 2022 were retrospectively analyzed. All patients completed neoadjuvant therapy for tumors, and the feasibility of radical surgical treatment was determined by a multidisciplinary collaborative team evaluation before surgery. According to whether the intraoperative artery was pre-occluded, 145 patients were divided into two groups, including 28 cases in the APOT group(16 males, 12 females, aged (59.0±9.4) years), and 117 cases in the routine surgery group(76 males, 41 females, aged (55.1±8.2) years). To ensure comparability of baseline data between the APOT group and the routine surgery group, a 1∶2 match was performed using the propensity score matching method, and the caliper value was 0.006 45. The t-test,the Mann-Whitney U test, χ2 test or Fisher′s exact test were used to compare the data between the two groups,respectively. Results:After matching the propensity score,there were 28 cases in the APOT group and 56 cases in the routine surgery group. There were no significant differences in gender,age,preoperative comorbidities,preoperative body mass index,surgical approaches,chemotherapy regimen,stereotactic body radiation therapy ratio,tumor markers,and type of invaded artery between the two groups (all P>0.05).The arterial occlusion time M(IQR) in the APOT group was 7.0(3.8)minutes(range:3 to 15 minutes),and no ischemic manifestations were observed in the distal target organs that blocked blood vessels after surgery. The operation time was (170.3±57.7)minutes in the APOT group and (235.0±80.2)minutes in the routine surgery group,and the difference was statistically significant ( t=-3.800, P<0.01). The APOT group also experienced less intraoperative blood loss(650(588)ml vs. 800(600)ml; U=1 026.500, P=0.021). No significant differences were found between the groups in combined vein resection and reconstruction,celiac trunk resection,early postoperative complications, readmission rates at 30 days,and postoperative length of stay(all P>0.05). Extra-arterial dissection was performed in all patients,with arterial resection and reconstruction in 3 cases: 2 cases in the APOT group(1 case involving the superior mesenteric artery and 1 case involving the common hepatic artery) and 1 case in the routine group(involving the common hepatic artery). Postoperative abdominal bleeding occurred in 4 cases,with 3 cases in the routine group,1 case in the routine group. The R0 resection rate was 85.7%(24/28) in the APOT group and 80.4%(45/56) in the routine group,without significant differences between the groups( P=0.763). The median overall survival time was 27.6 months for the APOT group and 22.5 months for the routine group,while the median disease-free survival was 11.7 months and 16.8 months,respectively,with no significant differences between the two groups( P=0.532, P=0.927). Conclusion:The arterial pre-occlusion technique can be used for extra-arterial dissection in patients with locally advanced pancreatic cancer involving the arteries,reducing surgery time and intraoperative blood loss.

Objective To explore the efficiency of artificial intelligence and radiomics-assisted X-ray in diagnosis of lumbar osteoporotic vertebral compression fractures(OVCF).Methods The clinical data of 455 patients diagnosed as lumbar OVCF by MRI in our hospital were selected.The patients were divided into the training group(n=364)and the validation group(n=91),X-ray films were extracted,the image delineation,feature extraction and data analysis were carried out,and the artificial intelligence radiomics deep learning was applied to establish a diagnostic model for OVCF.After verifying the effectiveness of the model by receiver operating characteristic(ROC)curve,area under the curve(AUC),calibration curve,and decision curve analysis(DCA),the efficiencies of manual reading,model reading,and model-assisted manual reading of X-ray in the early diagnosis of OVCF were compared.Results The ROC curve,AUC and calibration curve proved that the model had good discrimination and calibration,and excellent diagnostic performance.DCA demonstrated that the model had a higher clinical net benefit.The diagnostic efficiency of the manual reading group:the accuracy rate was 0.89,the recall rate was 0.62.The diagnostic efficiency of the model reading group:the accuracy rate was 0.93,the recall rate was 0.86,the model diagnosis showed good predictive performance,which was significantly better than the manual reading group.The diagnostic efficiency of the model-assisted manual reading group:the accuracy rate was 0.92,the recall rate was 0.72,and the recall rate of the model-assisted manual reading group was higher than that of the manual reading group,but lower than that of the model reading group,indicating the superiority of the model diagnosis.Conclusion The diagnostic model established based on artificial intelligence and radiomics in this study has reached an ideal level of efficacy,with better diagnostic efficacy compared with manual reading,and can be used to assist X-ray in the early diagnosis of OVCF.

Objective To develop a clinical prediction model for predicting risk factors for prolonged hospital stay after anterior cervical discectomy and fusion(ACDF).Methods The clinical data of 914 patients underwent ACDF treatment for cervical spondylotic myelopathy(CSM)were retrospectively analyzed.According to the screening criteria,800 eligible patients were eventually included,and the patients were divided into the development cohort(n=560)and the validation cohort(n=240).LASSO regression was used to screen variables,and multivariate Logistic regression analysis was used to establish a prediction model.The prediction model was evaluated from three aspects:differentiation,calibration and clinical effectiveness.The performance of the model was evaluated by area under the curve(AUC)and Hosmer-Lemeshow test.Decision curve analysis(DCA)was used to evaluate the clinical effectiveness of the model.Results In this study,the five factors that were significantly associated with prolonged hospital stay were male,abnormal BMI,mild-to-moderate anemia,stage of surgery(morning,afternoon,evening),and alcohol consumption history.The AUC of the development cohort was 0.778(95%CI:0.740 to 0.816),with a cutoff value of 0.337,and that of the validation cohort was 0.748(95%CI:0.687 to 0.809),with a cutoff value of 0.169,indicating that the prediction model had good differentiation.At the same time,the Hosmer-Lemeshow test showed that the model had a good calibration degree,and the DCA proved that it was effective in clinical application.Conclusion The prediction model established in this study has excellent comprehensive performance,which can better predict the risk of prolonged hospital stay,and can guide clinical intervention as soon as possible,so as to minimize the postoperative hospital stay and reduce the cost of hospitalization.

Objective To explore the risk factors for surgical site infection(SSI)after transforaminal lumbar interbody fusion(TLIF)for the treatment of lumbar degenerative diseases.Methods A total of 1 000 patients who underwent TLIF for lumbar degenerative diseases in our hospital were included and divided into the infection group(n=23)and the non-infection group(n=977)according to whether the surgical incision was infected.General data,surgical and laboratory indicators of patients were collected,and potential risk factors of SSI were screened by univariate analysis and multivariate regression analysis,a nomogram model was established,and its predictive efficiency was validated by the receive operating characteristic(ROC)curve.Results The incidence of SSI in patients after TLIF was 2.3％.The results of univariate analysis showed that age,operative time,intraoperative blood loss,preoperative C-reactive protein(CRP),smoking,and diabetes mellitus were the significant risk factors for the occurrence of SSI.Multivariate regression analysis showed that older age,longer operation time,more intraoperative blood loss,smoking and diabetes mellitus were the independent risk factors for postoperative SSI.ROC curve showed that the nomogram model established in this study has good predictive efficiency.Conclusion Older age,longer operation time,more intraoperative blood loss,smoking,and diabetes mellitus were independent risk factors for postoperative SSI.For patients with these high risk factors,corresponding intervention measures should be taken before operation to reduce the incidence of SSI.

Poly(dimethyl siloxane)(PDMS)is suitable for the fabrication of space cell culture chips.It is necessary to perform highly stable hydrophilic modification to promote cell adhesion on PDMS surface.We modified PDMS surface by oxygen plasma treatment combining with physical adsorption in this article.PDMS,which was treated with oxygen plasma and sequentially coated with Poly-L-lysine or collagen(PLL-ox-PDMS,COL-ox-PDMS)with various solution concentration and kept in different environmental conditions,were characterized by contact angle and surface energy measurements,and atomic force microscopy(AFM).Cell growth conditions on bare PDMS and modified PDMS were compared,and the numbers of live cells cultured for 1-3 days were evaluated.Experimental results indicate that higher solution concentration and low storage temperature benefit the hydrophilicity stability.The contact angles of PLL-ox-PDMS stored in 4℃and COL-ox-PDMS were close to 60°and 65°on day 25 and 14,respectively.Both modified PDMS surfaces are suitable for cell adhesion and proliferation,and no cell layer falls offin 10 days.The modification method is especially suitable for applications such as medium and long term space cell culture.