载HRZ乙酰乙酸涂层的自体髂骨修复兔脊柱结核骨缺损的病理学观察

Pathological observation on the repair of bone defect of spinal tuberculosis in rabbits with HRZ/PLGA coated autogenous iliac bone

中文关键词:  脊柱结核  缓释抗结核药  自体髂骨  骨修复  病理学

英文关键词:Spinal tuberculosis  Sustained anti-tuberculosis drugs  Autogenous iliac bone  Bone repair  Pathological

中文摘要:

  【摘要】 目的：观察载异烟肼、利福平、吡嗪酰胺/乙酰乙酸（HRZ/PLGA）涂层的自体髂骨修复兔脊柱结核骨缺损的病理学特点，以及材料对外周脏器的组织毒性。方法：将60只新西兰兔脊柱结核模型随机分为3组，每组20只，彻底病灶清除术后，A组（实验组）植入载HRZ/PLGA抗结核药缓释涂层的自体髂骨；B组（对照组）植入载空白涂层的自体髂骨；C组（空白对照组）单纯植入自体髂骨。术后第2、4、8、16周时各组随机抽取5只兔，取术区组织进行解剖大体观察和病理切片显微镜下观察，从组织病理学角度观察植骨界面愈合情况及植骨材料降解情况；术后第2周、4周留取A组兔的心、肝、脾、肾脏器制作病理标本观察抗结核缓释涂层材料对外周脏器有无组织毒性；术后第2、4、8、16周对A组（实验组）兔进行影像学检查（X线、CT、MRI），观察植骨融合情况。结果：解剖大体观察发现，A组兔观察至术后16周时，骨缺损处已由致密而规则的骨组织替代，硬度与周围骨组织相似，植骨界面已达骨性愈合，植骨材料的降解与整合已基本完毕；B、C组部分兔在观察至术后16周时可见椎旁淡黄色脓性物质形成，骨缺损处瘢痕增生明显，病变性骨桥形成，骨桥及邻近椎体可见虫蚀样破坏及缺损。镜下观察发现，A组兔观察至术后16周时骨缺损处板层骨及小梁骨生成增多，骨细胞增殖活跃，骨细胞形态及骨小梁结构完整并趋向成熟，未见炎性细胞及坏死物质形成；B、C组兔在观察至术后16周时有较多不规则的成骨细胞及纤细的骨小梁形成，新生骨小梁间可见炎性细胞聚集，部分有坏死物质形成。通过影像学观察A组实验兔的植骨愈合情况，至术后16周时，骨-材料界面结合紧密，植骨融合良好。对三组术后各时间点骨-材料界面的病理切片做骨小梁面积定量分析，观察至术后8周及16周时，A组骨小梁面积显著高于B组及C组（P＜0.01）。综上观察指标，A组兔脊柱结核病灶骨-材料界面愈合过程优于B组及C组（P＜0.05）。术后2周、4周时镜下观察A组兔的心、肝、脾、肾组织，均未见外周脏器损伤。结论：在病理学层面观察，载缓释抗结核药HRZ/PLGA涂层的自体髂骨植入兔脊柱结核骨缺损后有助于促进局部骨缺损的修复和病灶的治愈，对外周脏器无明显组织毒性，是一种良好的局部抗结核缓释材料。

英文摘要:

  【Abstract】 Objectives: To observe the pathological characteristics of bone defect of spinal tuberculosis in rabbits with autologous iliac bone coated with sustained-release anti-TB drug HRZ/PLGA and the toxicity to peripheral organs. Methods： 60 New Zealand rabbits of spinal tuberculosis models were randomly divided into 3 groups, 20 in each group, all underwent radical debridement. Group A(experimental group) was implanted with autologous iliac bone coated with sustained-release anti-TB drug HRZ/PLGA(isoniazid, rifampicin, pioglitazone/acetyl acetic acid); group B(control group) was implanted with autologous iliac bone with blank coating; group C(blank control group) was implanted with autogenous iliac bone. 5 rabbits were randomly selected at 2, 4, 8 and 16 weeks after operation and observed the tissues of bone graft by visual and microscopic view, the healing of implant interface and the degradation of bone graft material were studied by histopathological observation. The pathological specimens of heart, liver, spleen and kidney of group A at 2 weeks and 4 weeks after operation were made to specimen slices to observe the toxicity of peripheral organs. The imaging examinations(X-ray, CT, MRI) were performed at 2, 4, 8 and 16 weeks in experimental group after operation, and the fusion of bone graft was observed. Results: Visual observation in group A found that, at 16 weeks after operation, the bone defect was replaced by dense and regular bone tissue, the hardness was similar to the surrounding bone tissue, and the bone defect had reached the standard of bone healing, the degradation and integration of bone graft materials had been basically completed. In group B and group C, at 16 weeks after operation, some rabbits were observed formation of light-yellow purulent material, and scar hyperplasia was observed in bone defect and pathological bone bridge, paravertebral worm erosion damage and defect osteoid bridge could be seen. Microscopic observation in group A found that, at 16 weeks after operation, the production of lamellar bone and trabecular bone increased, the proliferation of bone cell was active, shape of bone cell and structure of trabecular bone were nearly mature, no inflammatory cells and necrotic materials formation. In group B and group C, at 16 weeks after operation, there were more irregular osteoblast and slender trabecular bone, inflammatory cell aggregation between trabecular bones, and necrotic material formed in some area. Imaging features of the bone graft healing of rabbits in group A were observed, and at the end of 16 weeks, the bone-material interface combined closely, bone graft healed good. At 8 weeks and 16 weeks after operation, the bone-material interface was made into pathological slice to quantitative analysis on the area of bone trabecular, and the bone trabecular area in group A was significantly higher than that in group B and group C(P＜0.05). In group A, no abscess, bone destruction, sequestrum, or caseous necrosis was observed at each time of observation, the healing of bone-material interface in group A was better than that in group B and group C(P<0.05). The heart, liver, spleen and kidney tissues of group A were observed at 2 weeks and 4 weeks after operation, no sign of peripheral organ damage was observed. Conclusions: The autologous iliac bone coated with sustained-release anti-TB drug HRZ/PLGA which was planted into the bone defect after debridement could promote the repair of bone defect and the healing of the lesion, no peripheral organ damage was observed. It has been proved to be a good sustained anti-tuberculosis material.