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Fracture non-unions affect many patients worldwide, however, known risk factors alone do not predict individual risk. The identification of novel biomarkers is crucial for early diagnosis and timely patient treatment. This study focused on the identification of microRNA (miRNA) related to the process of fracture healing. Serum of fracture patients and healthy volunteers was screened by RNA sequencing to identify differentially expressed miRNA at various times after injury. The results were correlated to miRNA in the conditioned medium of human bone marrow mesenchymal stromal cells (BMSCs) during in vitro osteogenic differentiation. hsa-miR-1246, hsa-miR-335-5p, and miR-193a-5p were identified both in vitro and in fracture patients and their functional role in direct BMSC osteogenic differentiation was assessed. The results showed no influence of the downregulation of the three miRNAs during in vitro osteogenesis. However, miR-1246 may be involved in cell proliferation and recruitment of progenitor cells. Further studies should be performed to assess the role of these miRNA in other processes relevant to fracture healing.全球范围内，骨不连（fracture non-unions）影响众多患者，但仅依靠已知风险因素无法精准预测个体发病风险。鉴定新型生物标志物对于实现早期诊断与及时施治至关重要。本研究聚焦于与骨折愈合过程相关的微小RNA（microRNA, miRNA）的鉴定工作。研究通过RNA测序（RNA sequencing）对骨折患者与健康志愿者的血清进行筛选，以鉴定损伤后不同时间点的差异表达微小RNA，并将测序结果与人骨髓间充质基质细胞（human bone marrow mesenchymal stromal cells, BMSCs）体外成骨分化过程中条件培养基内的微小RNA进行关联分析。研究人员在体外实验与骨折患者样本中均鉴定出hsa-miR-1246、hsa-miR-335-5p及miR-193a-5p，并评估了这三种微小RNA在骨髓间充质基质细胞直接成骨分化中的功能作用。结果显示，在体外成骨过程中，这三种微小RNA的下调并未对成骨分化产生影响。不过，miR-1246可能参与细胞增殖与祖细胞招募过程。未来需开展进一步研究，以明确这些微小RNA在骨折愈合相关其他生物学过程中的作用。