Association between fibrinogen concentration and nonunion in fracture patients

Nonunion (non-osteogenic healing) remains a major challenge in fracture management, particularly due to its diagnostic complexity and unpredictable occurrence in clavicle and femoral fractures. This study aimed to investigate the potential association between plasma fibrinogen concentration and the incidence of nonunion in fracture patients, with the objective of identifying a potential biomarker for clinical prediction. Based on retrospective data from Shandong Provincial Hospital Affiliated to Shandong First Medical University (January 2010 to May 2019), we analyzed a cohort of 338 fracture cases, among which 23 (6.8%) developed nonunion. Fibrinogen concentration (AUC = 0.635, 95% CI 0.517-0.752) showed moderate discriminative capability for nonunion. Using smoothing curve fitting techniques and multivariable logistic regression models, the study systematically assessed the dose-response relationship between fibrinogen levels and the risk of nonunion risk, adjusting for confounding factors such as age, sex, injury mechanism, and ASA classification. The results indicated that for every 1 g/L increase in fibrinogen concentration, the risk of nonunion increased significantly by 48% [adjusted odds ratio [OR] = 1.48, 95% confidence interval [CI] not explicitly reported but implied statistical significance]. This association remained statistically significant even after controlling for traditional risk factors such as trauma severity and baseline patient status, suggesting that fibrinogen may influence bone healing through independent pathways. Smoothing curve fitting revealed a nonlinear, dose-dependent increase in nonunion risk with higher fibrinogen levels, potentially guiding the establishment of clinical threshold settings. The study found that elevated plasma fibrinogen levels are independently associated with an increased risk of nonunion, and routine monitoring of fibrinogen concentrations may serve as a promising adjunct tool for early identification of at-risk patients. Future research should focus on elucidating the underlying mechanisms-such as inflammation regulation and extracellular matrix deposition-and validating the predictive value of fibrinogen across different types of fractures to support the development of personalized treatment strategies.