Influencing factors of traumatic arthritis after ankle fracture surgery and construction of risk prediction model

Abstract

To explore risk factors of post-operative traumatic arthritis in patients with ankle fracture,and to establish risk prediction model. Totally 550 patients with ankle fracture treated from May 2020 to May 2022 were selected as research objects and divided into modeling group (385 patients) and verification group (165 patients) according to 7:3. In modeling group,patients were classified as occurrence group (112 patients) and non-occurrence group (273 patients) according to whether traumatic arthritis occurred after opertaion. Age,body mass index(BMI),gender,smoking history,diabetes history,injury type,fracture type,operation time,manual labor,open injury,osteoporosis,poor reduction,postoperative weight-bearing time,vascular injury,and surgical method were recorded; risk factors of traumatic arthritis in ankle fracture patients were analyzed by single factor and multi factor logistic regression analyses; R software was used to build the prediction model of line graph;receiver operating characteristic (ROC) curve and calibration graph were applied to verify the discrimination and consistency of the model. One hundred and twelve of 385 patients with ankle fracture were developed to post-operative traumatic arthritis,and 275 did not. Univariate analysis showed that there were significant differences in age,BMI,fracture type,operation time,physical labor aboveⅡ,open injury,osteoporosis and poor reduction between two groups (P<0.05). Multivariate Logistic regression analysis showed that age (OR=2.887),BMI (OR=4.042),fracture type (OR=4.244),operation time (OR=2.665),physical labor above gradeⅡ(OR=5.099),osteoporosis (OR=10.219),and poor reduction (OR=3.112) were independent risk factors for traumatic arthritis after ankle fracture (P<0.05). Based on the above risk factors,an nomogram model was established to predict the risk of postoperative traumatic arthritis in ankle fracture patients,and internal and external verification was conducted. The results showed calibration curve of modeling group and verification group showed a good fit between correction curve and ideal curve,indicating that the predicted risk of postoperative traumatic arthritis by the model was basically consistent with actual risk. Area runder ROC curve analysis results showed 0.867[(95%CI(0.826,0.908)] and 0.882 [95%CI(0.827,0.938)],respectively,indicating that the prediction model had good prediction ability. Age,BMI,fracture type,operation time,physical labor above gradeⅡ,osteoporosis and poor reduction are all risk factors for post-operative traumatic arthritis in patients with ankle fracture. The prediction model based on the above risk factors could effectively evaluate risk of post-operative traumatic arthritis in patients with ankle fracture.