Results
pilon fracture, pneumonia, fracture
REGRESSION, PNEUMONIA
From January 2012 to June 2021, 516 pilon fracture patients who underwent open reduction and internal fixation were included in this study. Of these, 387 patients were randomly assigned to the training group and 129 patients were assigned to the validation group (3:1). The baseline data of the training group and the validation group were analyzed, and there was no significant difference between the two groups (Table Baseline characteristicsData are presented as the mean and the standard deviation with the range in parenthesis or expressed as the number with the percentage in parenthesis. *P-value, differences between patients with pneumonia and controlIn univariate analyses of the training group, the significant risk factors were age, preoperative blood sugar, Tscherne classification, fracture classification, operative time and surgical approach (Multivariable logistic regression of predictors for SSIData are presented as the odds ratio with the confidence interval in parenthesis. OR, odds ratio; CI, confidence intervalThen, we built a nomogram to predict SSI, including five independent risk factors based on multivariate logistic regression analysis (Fig. The nomogram predictive model for SSI. To use the nomogram, the points corresponding to each prediction variable were obtained, then the sum of the points was calculated as the total score, and the predicted risk corresponding to the total score was the probability of SSIThe validation of the model was based on discrimination and calibration. We plotted the ROC curve of the predictive model and calculated the AUC value. The AUC values for SSI of the training and validation group were 0.898 and 0.880 respectively, proving that this nomogram model had good discriminative power (Fig. ROC curves for validating the discrimination of the nomogram predictive model (training group AUC = 0.898, validation group AUC = 0880)Calibration plot of the nomogram for the probability of SSI