Association between timing of surgery and refracture after initial osteoporotic fractures

Osteoporotic refracture may result from multiple risk factors. However, few studies have explored the association between the interval from the initial fracture to surgery (i.e., the timing of surgery) and osteoporotic refracture. This study aims to investigate the significant risk factors of osteoporotic refracture and to provide more reliable interventions for its prevention. A total of 502 hospitalized patients with osteoporotic fractures from January 2017 to December 2022 at Nanjing Medical University Affiliated Wuxi People's Hospital were retrospectively analyzed. This included 52 cases in the refracture group and 450 cases in the non-refracture group. Univariate analysis revealed significant differences between the refracture and non-refracture groups. These differences included age, height, body mass index (BMI), bone mineral density (BMD), hemoglobin concentration, total serum protein concentration, pain level, and the interval from fracture to surgery. Further binary logistic regression and Cox proportional hazard regression both indicated that the interval from fracture to surgery, pain level, and age were independent risk factors for refracture. According to the results of receiver operating characteristic (ROC), the prediction accuracy of interval time was high, with area under ROC (AUC) of 0.782, sensitivity of 63.5%, specificity of 84.4%, and threshold value of 10.5. Our study suggests that a longer interval from initial fracture to surgery is associated with an increased risk of refracture, with 10.5 days being the optimal threshold based on ROC analysis.