Abstract: Objective To investigate the correlation between the expression of serum microRNA-21-5p (miR-21-5p),microRNA-1224-5p (miR-1224-5p),and microRNA-181a-5p (miR-181a-5p) with postoperative delayed healing in patients with femoral neck fracture (FNF).Methods From October 2021 to April 2024,371 patients with FNF admitted to our hospital were included as subjects.The patients were assigned into a study group (delayed healing,68 cases) and a control group (normal healing,303 cases) based on whether the fracture ends healed 4 months after surgery.Real-time fluorescence quantitative PCR (qRT-PCR) was applied to detect the expression levels of serum miR-21-5p,miR-1224-5p,and miR-181a-5p.Multivariate Logistic regression was applied to analyze the influencing factors of postoperative healing delay in FNF patients.ROC curve was applied to analyze the predictive value of serum miR-21-5p,miR-1224-5p,and miR-181a-5p for postoperative healing delay in FNF patients.Results The levels of serum miR-21-5p,miR-1224-5p,and miR-181a-5p in the study group were lower than those in the control group (P<0.05).Multivariate Logistic analysis showed that age ≥60 years old,diabetes,and smoking were risk factors for postoperative delayed healing in FNF patients (P<0.05),and miR-21-5p,miR-1224-5p and miR-181a-5p were protective factors for postoperative delayed healing in FNF patients (P<0.05).ROC curve showed that the AUC values of miR-21-5p,miR-1224-5p,and miR-181a-5p for predicting postoperative healing delay in FNF patients were 0.845,0.809,and 0.797,respectively.When the three were combined for prediction,the AUC increased to 0.933.The combined detection effect of the three indicators was better than that of any individual indicator (Z_combination vs. miR-21-5p=3.444,Z_combination vs. miR-1224-5p=4.401,Z_combination vs. miR-181a-5p=4.279,P<0.05).Conclusion The levels of serum miR-21-5p,miR-1224-5p,and miR-181a-5p are reduced in FNF patients with postoperative delayed healing.The combined detection of the three may have a certain predictive value for postoperative delayed healing in FNF patients.

Key words: femoral neck fracture, miR-21-5p, miR-1224-5p, miR-181a-5p, delayed healing