Prediction model of preoperative deep vein thrombosis of lower limbs by nomogram in pa-tients with tibial plateau fractures

Tang Zhuodong; Wang Mingyou; Wang Hongping; Li Tingyan; Wang Chuan; Liu Shaojiang

doi:10.3969/j.issn.1009-4237.2025.01.009

Abstract：Objective To explore the risk factors of preoperative deep vein thrombosis(DVT)of lower ex-tremities in patients with tibial plateau fractures,and to construct and verify a risk prediction model.Methods Clinical data of 166 patients with tibial plateau fractures admitted to Panzhihua Central Hospital from Jan.2018 to Jan.2024 were retrospectively analyzed.There were 108 males and 58 females aged 22-76(mean 49.3)years.Among them,69 were due to ground-level falls,64 to road traffic accidents and 33 to falls from height,with 91 cases of Schatzker type Ⅰ-Ⅲ and 75 types Ⅳ-Ⅵ.According to the results of whether developing lower limb DVT before surgery,confirmed by the color Doppler ultrasound,patients were divided into DVT group(n=50)and non-DVT group(n=116).Independent risk factors for preoperative DVT were determined by univariate analysis and multiva-riate Logistic regression analysis,and then the nomogram prediction model was constructed,whose predictive efficacy was further verified by the receiver operator characteristic(ROC)curve,calibration curve and decision curve analy-sis(DCA)curve.Results Among the 166 patients included in the study,50 were diagnosed to have preoperative DVT,with the incidence being 30.1％(95％CI:0.231-0.372).Univariate analysis showed that age,injury causes,time from injury to surgery,and preoperative D-dimer level were significantly different between the two groups(all P<0.05).Multivariate Logistic regression analysis further showed that age≥47.5 years and preoperative D-dimer level≥2422.5 ng/mL were independent risk factors for preoperative DVT in patients with tibial plateau fracture.ROC curve revealed that the area under the ROC curve(AUC)of the model was 0.960(95％CI:0.929-0.991),the sensitivity was 88.0％,and the specificity reached 95.6％.The calibration curve showed that the model had good consistency.DCA curve showed that the net clinical benefit of the model was high in the threshold range of 0-1.Conclusion Age≥47.5 years and preoperative D-dimer≥2422.5 ng/mL are independent risk factors for preop-erative DVT in patients with tibial plateau fractures.The constructed model has good differentiation and consistency,and can be used to predict the risk of DVT of lower limbs in patients with tibial plateau fractures.