To construct a prediction model for refracture in 2-year in elderly patients with limb fracture, and verify its prediction efficacy.

A total of 148 elderly patients with limb fracture treated in our hospital from January 2020 to December 2020 were selected as the training group, which was used to construct the nomogram prediction model, and the Boot-strap method was used for internal verification. A total of 86 elderly patients with limb fracture treated in our hospital from January 2021 to July 2021 were selected as the verification group to conduct external verification of the prediction model.

In the training group, 148 patients were followed up for 2 years, 6 cases were lost to follow-up, 142 cases were effectively followed up, and 27 cases were re-fractured, with an incidence of 19.01% (27/142). In the training group, the number of women with refracture in the 2-year, combined with diabetes, malnutrition, combined with osteoporosis, loose fixation, glucocorticoid use, living alone was higher than that of patients without refracture, the age was higher than that of patients without refracture, and the skeletal muscle index of limbs, early load exercise, and calcium supplement were lower than that of patients without refracture (P<0.05). Skeletal muscle index of limbs was an independent protective factor for refracture in the 2-year in the training group, and age, diabetes mellitus, osteoporosis and living alone were independent risk factors (P<0.05). According to the Logistic regression analysis results, a risk prediction model for refracture of patients in the 2-year was constructed. logit (P)=-14.622+0.220×age -0.521×skeletal muscle index of limbs+1.724×diabetes mellitus +1.485×osteoporosis +1.282×solitude. The Hosmer-Lemeshow goodness of fit test showed that χ²=6.411, DF=8, P=0.601, indicating a good fit. The internal verification showed that C-index was 0.833 with good differentiation, Brier score was 0.107, calibration slope was 0.666, and calibration degree was good. External verification showed that AUC value was 0.897, 95%CI was 0.810-0.953, sensitivity was 77.78%, specificity was 85.94%, and it had good discrimination ability. Hosmer-Lemeshow test showed good fit, Brier score was 0.094, and calibration slope was 0.793. Good calibration.

Elderly patients with limb fracture have a high incidence of refracture in the 2-year, and the influencing factors include age, skeletal muscle index of limbs, combined with diabetes, combined with osteoporosis, and living alone. Medical personnel should conduct targeted management of high-risk groups according to the characteristics of patients and high-risk factors to reduce the incidence of refracture.