BACKGROUND:The most common complication of traumatic femoral neck fractures after internal fixation is femoral head necrosis.Currently,many studies have reported on the risk factors that affect the occurrence and development of postoperative femoral head necrosis,but there is still a lack of tools to predict the risk of femoral head necrosis after internal fixation of femoral neck fractures.OBJECTIVE:To develop a predictive model that estimates the risk of femoral head necrosis shortly after patients with femoral neck fractures receive cannulated screw internal fixation.METHODS:A retrospective analysis reviewed clinical records of 172 patients who underwent cannulated screw internal fixation for femoral neck fractures at Department of Orthopedics of Mianyang Central Hospital from January 2013 to June 2023.Patients were categorized into two groups based on the presence or absence of femoral head necrosis within one year post-operation:the necrosis group and the non-necrosis group.Univariate analysis,Lasso regression,and multivariate Logistic regression techniques were employed to identify the determinants of femoral head necrosis.A nomogram prediction model was constructed using R language's"rms"package,version 4.0.The receiver operating characteristic curve was used to evaluate the discriminatory ability of the model.The Hosmer-Lemeshow test was used to evaluate the goodness of fit of the model,and the decision curve analysis was used to determine its clinical application benefits.Internal validation of the study was conducted using the Bootstrap method,involving 1 000 repeated samplings.To delve deeper into the primary factors influencing femoral head necrosis post-internal fixation of the femoral neck,this paper employed the SHAP method for data set analysis.RESULTS AND CONCLUSION:(1)The risk factors leading to femoral head necrosis in the short term after cannulated screw fixation of femoral neck fractures include:smoking,diabetes,Garden classification,fracture line location,reduction quality,age,and operation time.(2)The prediction model demonstrated robust performance,evidenced by an area under the curve of 0.940(95％Confidence Interval:0.903 to 0.977),indicating a high level of prediction accuracy.The model achieved a sensitivity of 90.2％and a specificity of 87.6％,indicating that its diagnostic performance was stable.The Hosmer-Lemeshow goodness-of-fit test yielded a chi-square value of 6.593 with a P-value of 0.581,confirming that the model's predictions closely align with the observed outcomes.(3)The calibration curve of the model also performed well,and its overall trend was very close to the ideal curve,further proving the high accuracy of the model.(4)The internal validation was carried out by the Bootstrap method with 1 000 repeated samplings,and the area under the curve of the model internal validation was still as high as 0.939,proving that the model had good stability.(5)Through the decision curve,it is found that within the probability threshold range of 1％to 92％,the model can obtain the maximum net benefit value.(6)The SHAP analysis results show that among the risk factors analyzed in this study,the location of the fracture line serves as the most significant predictor of femoral head necrosis following internal fixation with cannulated screws in femoral neck fractures,and subcapital fractures are extremely prone to femoral head necrosis after surgery.(7)It is concluded that the validated prediction model demonstrates strong discriminative power and reliability,offering practical clinical utility.It serves as a useful reference tool for short-term risk assessment of femoral head necrosis following internal fixation of femoral neck fractures.

BACKGROUND:The most common complication of traumatic femoral neck fractures after internal fixation is femoral head necrosis.Currently,many studies have reported on the risk factors that affect the occurrence and development of postoperative femoral head necrosis,but there is still a lack of tools to predict the risk of femoral head necrosis after internal fixation of femoral neck fractures.OBJECTIVE:To develop a predictive model that estimates the risk of femoral head necrosis shortly after patients with femoral neck fractures receive cannulated screw internal fixation.METHODS:A retrospective analysis reviewed clinical records of 172 patients who underwent cannulated screw internal fixation for femoral neck fractures at Department of Orthopedics of Mianyang Central Hospital from January 2013 to June 2023.Patients were categorized into two groups based on the presence or absence of femoral head necrosis within one year post-operation:the necrosis group and the non-necrosis group.Univariate analysis,Lasso regression,and multivariate Logistic regression techniques were employed to identify the determinants of femoral head necrosis.A nomogram prediction model was constructed using R language's"rms"package,version 4.0.The receiver operating characteristic curve was used to evaluate the discriminatory ability of the model.The Hosmer-Lemeshow test was used to evaluate the goodness of fit of the model,and the decision curve analysis was used to determine its clinical application benefits.Internal validation of the study was conducted using the Bootstrap method,involving 1 000 repeated samplings.To delve deeper into the primary factors influencing femoral head necrosis post-internal fixation of the femoral neck,this paper employed the SHAP method for data set analysis.RESULTS AND CONCLUSION:(1)The risk factors leading to femoral head necrosis in the short term after cannulated screw fixation of femoral neck fractures include:smoking,diabetes,Garden classification,fracture line location,reduction quality,age,and operation time.(2)The prediction model demonstrated robust performance,evidenced by an area under the curve of 0.940(95％Confidence Interval:0.903 to 0.977),indicating a high level of prediction accuracy.The model achieved a sensitivity of 90.2％and a specificity of 87.6％,indicating that its diagnostic performance was stable.The Hosmer-Lemeshow goodness-of-fit test yielded a chi-square value of 6.593 with a P-value of 0.581,confirming that the model's predictions closely align with the observed outcomes.(3)The calibration curve of the model also performed well,and its overall trend was very close to the ideal curve,further proving the high accuracy of the model.(4)The internal validation was carried out by the Bootstrap method with 1 000 repeated samplings,and the area under the curve of the model internal validation was still as high as 0.939,proving that the model had good stability.(5)Through the decision curve,it is found that within the probability threshold range of 1％to 92％,the model can obtain the maximum net benefit value.(6)The SHAP analysis results show that among the risk factors analyzed in this study,the location of the fracture line serves as the most significant predictor of femoral head necrosis following internal fixation with cannulated screws in femoral neck fractures,and subcapital fractures are extremely prone to femoral head necrosis after surgery.(7)It is concluded that the validated prediction model demonstrates strong discriminative power and reliability,offering practical clinical utility.It serves as a useful reference tool for short-term risk assessment of femoral head necrosis following internal fixation of femoral neck fractures.

Objective To rvaluate the therapeutic efficacy of balloon-dilatation covered stents in the treatment of renal artery stenosis(RAS).Methods The clinical data of 30 patients with RAS,who received intravascular ultrasonography(IVUS)-guided LifeStream balloon-dilatation covered stent implantation at the Affiliated Central Hospital of Dalian University of Technology(Dalian Municipal Central Hospital)of China from August 2022 to December 2023,were retrospectively analyzed.The various parameters of the lumen and the stent were measured,and the performance of the stent was evaluated.Results The minimum original blood vessel diameter below the base of the stenotic segment plaque was 5.40(5.17,5.80)mm and the maximum blood vessel diameter was 6.20(5.80,6.93)mm,which became 6.00(5.80,6.00)mm and 7.90(6.00,8.00)mm respectively after stent release,the differences were statistically significant(both P＜0.05).Before stent release the luminal eccentricity index was(14.72±9.37)％,which was(1.54±9.16)％after stent release,the difference was statistically significant P＜0.05).The instant stent symmetry after stent release was(82.69±14.61)％,and the stent expansion factor was(99.81±10.70)％.Ideal narrow coverage rate was obtained.During operation,poor stent adhesion occurred in 2 patients and renal artery rupture with bleeding occurred in one patient,which were solved after immediate re-expansion treatment.Spearman's correlation analysis showed that stent symmetry,stent expansion factor,and stent eccentricity index did not linearly correlate with the lumen cross-sectional area stenosis rate and the plaque eccentricity index(all P＞0.05).Conclusion For the treatment of RAS,the LifeStream balloon-dilatation covered stent is clinically safe,feasible,and effective with satisfactory immediate clinical outcomes.

Objective To observe the value of intravascular ultrasound(IVUS)for assisting endovascular therapy for renal artery stenosis(RAS).Methods Thirty patients with RAS who underwent endovascular therapy were retrospectively analyzed.Parameters of renal artery and plaques in RAS segment measured with CT angiography(CTA)and IVUS before treatment were compared.Bland-Altman diagram was performed to evaluate the consistency of lumen cross-sectional stenosis rate and plaque eccentricity index between CTA and IVUS.The stent parameters measured with IVUS were recorded immediately after implantation of balloon-expandable covered stents.Results Before treatment,the minimum lumen diameter,lumen cross-sectional stenosis rate and stenotic segment length of IVUS were all larger,while maximum lumen diameter and lumen eccentricity index of IVUS were both smaller than those of CTA(all P＜0.05).No significant difference of plaque eccentricity index,plaque type nor stenosis distal remodeling was found between CTA and IVUS(all P＞0.05).The average difference between IVUS and CTA for evaluating lumen cross-sectional stenosis rate and plaque eccentricity index was-0.020(-0.096,0.050)and-0.020(-0.130,0.091),respectively.The consistency of IVUS and CTA for evaluating plaque eccentricity index was better than that of lumen cross-sectional stenosis rate.The stent symmetry,stent eccentricity index,stent expansion coefficient and stenosis coverage rate immediately after implantation measured with IVUS was(82.69±14.61)%,(1.54±9.16)%,(99.81±10.70)%and 100%,respectively.Among 30 cases,2 cases(2/30,6.67%)underwent postdilation since poor stent apposition.Conclusion IVUS could assist evaluating lumen and plaque parameters of stenotic renal arteries,guiding stent release and real-timely monitoring the effect of endovascular therapy.

Objective    To evaluate the short-term therapeutic effect of extended adventitial inversion with graft eversion anastomosis technique in the root treatment of acute type A aortic dissection (ATAAD). Methods    From November 2019 to July 2020, 28 patients with ATAAD were treated by extended adventitial inversion with graft eversion anastomosis technique in the Department of Cardiovascular Surgery, Dalian Municipal Central Hospital, including 19 males and 9 females, aged 60.11±11.11 years. The intima of the ascending aorta was trimed to 5 mm above the sinotubular junction. The adventitia of the ascending aorta was longitudinally cut to the reserved intima margin along the junction of the three aortic valves. The extended adventitial inversion was sutured continuously, no coronary sinus was sutured over the aortic annulus, and the left and right coronary sinus was sutured above the coronary ostium. The anastomotic graft was everted and inserted into the aortic lumen, and the everted graft was continuously sutured at the level of sinotubular junction which was 5 mm away from the edge of graft. Results    There was no intraoperative death, intractable root hemorrhage, residual root false lumen, root dilatation, anastomotic hematoma or other complications. There was no recurrence of the pain in the back of all patients, and the results of the CT angiography were not significantly changed. In 22 patients with no regurgitation, only 1 (4.55%) patient had a mild regurgitation. In 6 patients with mild aortic regurgitation, the disappearance rate of regurgitation was 50.0% (3/6). Conclusion    The treatment of extended adventitial inversion with graft eversion anastomosis technique in the root treatment of aortic dissection eliminates the residual dissection at the root. The anastomotic hemorrhage is prevented, the root structure of aortic dissection is reconstructed and strengthened, the root function is restored, and the possible expansion of the root is prevented. The short-term results are satisfactory.

Due to the emergence of various treatment methods for aortic diseases, the treatment methods of anastomosis have become diversified.The anastomosis of the graft distal eversion partly inserted into the aorta or graft inversion wholely inserted into the aorta increase the joint area between them, and it obviously reduces the impact of tidal blood flow and the lateral force on the anastomosis.Therefore, it has the outstanding advantages of reducing the risk of hemorrhage after anastomosis, simplifying the intraoperative suture operation and easy treatment of anastomotic hemorrhage.Similar techniques with different names are often used in the surgical treatment of aortic lesions and have achieved good anastomosis.In this paper, the concept is uniformly referred to as " Graft Eversion Anastomosis Technique" , and its application evolution in aortic surgery is systematically expounded, so as to further deepen the understanding of the technology.

Objective: To investigate the effect of zinc sulfate and zinc methionine on growth and their possible regulating mechanism in mice. Method: Ninety male KM mice were randomly divided into three groups. The control group was fed on basal diet containing zinc of 11. 67 mg/kg 10d. The ZnSO4 group and Zn-Met group were fed on the diets supplemented with ZnSO4 or Zn-Met at 30 mg/kg(on the basis of Zn) for 10 d. Initial and final body weight,serum zinc concentration, growth hormone (GH),the levels of growth hormone receptor (GHR) and insulin like growth factor 1 (IGF-1) mRNA were determined. Results: Both ZnSO4 and Zn-Met enhanced body weight and serum zinc concentration of mice,Zn-Met more effectively than ZnSO4 for body weight . Both forms of zinc had no effect on GH and the expression of GHR mRNA , but both up-regulated the expression of IGF-1 mRNA. As compared to ZnSO4, Zn-Met enhanced the level of IGF-1 mRNA significantly. Conclusion: Both ZnSO4 and Zn-Met had no effect on GH and the expression of GHR Mrna,but enhanced the expression of IGF-1 mRNA. Zn-Met enhanced the body weight gain and up-regulated IGF-1 mRNA expression more effectively than ZnSO4.