目的 研究组织工程骨结合带锁髓内钉修复成年山羊大段负重骨缺损的可行性，探索更可行的技术路径。 方法 将24只成年山羊，通过骨髓穿刺法获取山羊骨髓间充质干细胞（BMSC），将体外扩增及成骨定向诱导的第2代BMSC与同种异体脱钙骨基质（DBM）通过双相接种法构建组织工程骨。24只成年山羊，以带锁髓内钉构建股骨中段3 cm骨缺损模型。随机分为3组，每组8只。实验组以组织工程骨修复骨缺损，对照组单独使用DBM和空白组旷置。术后1、12、24周行X线片观察及评分，12、24周每组各处死4只动物行组织学观察和生物力学检测。 结果 标本大体观察示实验组和对照组术后12周骨缺损部位被骨痂连接，髓腔贯通，24周全部愈合；实验组24周恢复正常解剖形态，对照组外形仍然粗糙、不规则；空白组术后12周及24周缺损部位均为纤维组织充填。术后1周各组X线评分无明显差异（P＞0.05），实验组术后12周及24周X线评分均优于对照组和空白组，对照组优于空白组，各组24周X线评分均高于12周时，差异均有统计学意义（P＜0.05）。实验组术后12、24周的最大抗扭强度分别达正常侧的47.07% ± 5.05%和83.73% ± 2.33%，显著高于对照组和空白组（P＜0.05）；空白组2个时间点最大抗扭强度均不超过正常的15%，与骨不连时的纤维连接相符。组织学检查示术后12周实验组和对照组骨缺损区DBM支架材料基本被吸收，有典型的同心圆排列的哈弗系统形成，周围偶见淋巴细胞；术后24周，实验组和对照组股骨缺损均被修复，但实验组较对照组的新骨更多、骨塑形更好；空白组术后24周骨缺损区中央仍为纤维组织填充。 结论 组织工程骨结合带锁髓内钉能够更有效修复成年山羊负重骨大段骨缺损，满足负重骨的生物力学要求。
ObjectiveTo review and summarize the research progress on repairing segmental bone defects using three-dimensional (3D)-printed bone scaffolds combined with vascularized tissue flaps in recent years. MethodsRelevant literature was reviewed to summarize the application of 3D printing technology in artificial bone scaffolds made from different biomaterials, as well as methods for repairing segmental bone defects by combining these scaffolds with various vascularized tissue flaps. Results The combination of 3D-printed artificial bone scaffolds with different vascularized tissue flaps has provided new strategies for repairing segmental bone defects. 3D-printed artificial bone scaffolds include 3D-printed polymer scaffolds, bio-ceramic scaffolds, and metal scaffolds. When these scaffolds of different materials are combined with vascularized tissue flaps (e.g., omental flaps, fascial flaps, periosteal flaps, muscular flaps, and bone flaps), they provide blood supply to the inorganic artificial bone scaffolds. After implantation into the defect site, the scaffolds not only achieve structural filling and mechanical support for the bone defect area, but also promote osteogenesis and vascular regeneration. Additionally, the mechanical properties, porous structure, and biocompatibility of the 3D-printed scaffold materials are key factors influencing their osteogenic efficiency. Furthermore, loading the scaffolds with active components such as osteogenic cells and growth factors can synergistically enhance bone defect healing and vascularization processes. ConclusionThe repair of segmental bone defects using 3D-printed artificial bone scaffolds combined with vascularized tissue flap transplantation integrates material science technologies with surgical therapeutic approaches, which will significantly improve the clinical treatment outcomes of segmental bone defect repair.