Abstract: Objective To analyze the risk factors of lower limb deep vein thrombosis (DVT) after the closed Pilon fracture surgery,and to build a nomograph prediction model.Methods A total of 182 patients with closed Pilon fracture who underwent surgical treatment in our hospital from June 2019 to June 2022 were retrospectively analyzed,according to the occurrence of postoperative DVT, the patients were divided into two groups: 43 cases in DVT group and 139 cases in non-DVT group.Univariate and multivariate Logistic regression analysis was applied to screen the risk factors of lower limb DVT after closed Pilon fracture surgery;R software was applied to build a nomograph model for predicting lower limb DVT after closed Pilon fracture surgery,and receiver operating characteristic(ROC) and calibration curve were applied to verify the nomograph model.Results Logistic regression analysis showed that the history of diabetes mellitus, risk assessment of thrombosis as medium and high risk, and postoperative infection were independent risk factors for lower limb DVT after closed Pilon fracture surgery (P＜0.05).The area under the ROC curve was 0.716 (95%CI:0.629-0.804).The slope of calibration curve was close to 1,and H-L goodness of fit test χ²=2.556,P=0.635.Conclusion The history of diabetes,the result of thrombosis risk assessment as “medium-high risk”,and the postoperative infection occurred at the surgical site are independent risk factors for lower limb DVT after closed Pilon fracture surgery.The nomogram prediction model constructed by integrating the above three independent risk factors can effectively predict lower limb DVT after closed Pilon fracture surgery,with high differentiation and consistency.

Key words: closed Pilon fracture；postoperative；lower limb deep venous thrombosis；risk factors；nomogram prediction model