联合钙盐骨水泥及可降解网状微孔球囊椎体成形的体外实验

背景：椎体成形、椎体后凸成形治疗骨质疏松性椎体压缩性骨折中存在骨水泥外溢、伤椎及临近椎体继发骨折等风险。目的：验证高分子可降解网状微孔球囊应用于骨质疏松性椎体压缩骨折的可行性。方法：以聚乳酸-已内酯共聚物为原材料，采用静电纺丝技术制备可降解网状微孔球囊，同时制备涂层球囊，扫描电镜观察其形貌；向球囊内分别注入水和骨水泥，观察外渗情况；测试球囊的断裂强度和断裂伸长率。采用细胞染色法和CCK-8法测试小鼠胚胎成骨细胞在两种球囊上的增殖情况。观察两种球囊在模拟体液、猪胰脂肪酶溶液和新鲜的人血清中的降解。将球囊置入猪椎体后测试球囊的爆破压。将钙盐骨水泥注入球囊后密封，固化后置于6 atm压力的超纯水中，定期检测钙离子浓度。结果与结论：网状微孔球囊具有良好的纤维形态，粗细分布均匀，存在孔隙；涂层球囊表面无具体形态结构及孔隙存在。与涂层球囊相比，网状微孔球囊具有更好的力学性能和液体渗透性及爆破压力，可防止骨水泥渗漏，促进成骨细胞的黏附与增殖，降解更均匀、稳定，可较好保持钙离子浓度，更利于新骨生长和骨折愈合。中国组织工程研究杂志出版内容重点：生物材料；骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性；组织工程全文链接：

Performance testing of biodegradable mesh-like microporous balloon combined with calcium phosphate cement for vertebroplasty

BACKGROUND:Vertebroplasty and kyphoplasty for osteoporotic vertebral compression fractures can result in many complications, such as bone cement leakage and adjacent-level fractures.OBJECTIVE:To verify the possibility of biodegradable mesh-like microporous polymer balloon for the treatment of osteoporotic vertebral compression fractures.METHODS: Biodegradable mesh-like microporous P(DLLA-CL) balloons were fabricated by electrospinning technique. Coated balloons with the same specification was fabricated by coating P(DLLA-CL) onto the same mould. Morphology of the balloons was observed by scanning electron microscopy. The balloon leakage was observed by eyes after the injection of water or cement. The initial strength and stiffness were measured by a universal testing machine. The proliferation of MC3T3-E1 cells on the balloons was determined by laser confocal microscope and cell counting kit-8 assays. The biodegradation of balloons in simulated body fluid, porcine pancreatic lipase, and fresh human serum was studied by residual weighing and scanning electron microscopy observation. Burst pressure of balloons was measured after the balloon was placed into a hole in the vertebral bone. For the in vitro calcium release tests, the balloons were filled with calcium cement, tied, placed into 6atm ultrapure water, and then the calcium concentration was regularly determined.RESULTS AND CONCLUSION:Mesh-like microporous balloons presented with good fiber morphology, thickness distribution, and the presence of pores; on the coated balloon surface, there was absence of specific morphology and porosity. Compared with the coated balloon, the mesh-like microporous balloon showed better mechanical properties, liquid permeability and burst pressure, to prevent leakage of bone cement and promote osteoblast adhesion and proliferation. In addition, the degradation of the mesh-like microporous balloons was more uniform and stable than the coated balloons, which may increase the calcium concentration in the injured vertebrae and will be beneficial to the new bone growth and fracture healing.