不同神经损伤对骨折前期愈合影响的实验研究

Experimental observation of rat's early-stage fracture healing with different kinds of nerve injuries

目的: 研究脊髓和周围神经损伤对骨折前期修复的影响。方法: 将实验大鼠分成3组, 一组为T10脊髓横断伴股骨骨折, 另两组分别为周围神经切断伴股骨骨折组和单纯股骨骨折组。骨折后2周和4周摄股骨X线片, 4周处死大鼠行骨痂细胞和组织学检查。结果: 骨折后2周3组均未出现明显骨痂, 术后4周测量X线片骨痂大小显示周围神经切断组骨痂最多, 其次分别为对照组和脊髓损伤组。组织学显示周围神经切断组骨痂量多, 并有明显的皮质骨桥接断端, 但其中类骨质较多, 骨钙的沉积相对较少, 而且骨痂缺乏血管和正常的骨小梁结构, 骨化重建不够理想; 而脊髓损伤组骨痂则表现为欠成熟, 细胞种类多, 分布紊乱, 少部分仍处于纤维修复阶段。对照组的组织学改变介于两者之间, 但其骨小梁结构良好而且骨钙沉着明显。结论: 不同类型神经损伤对骨折愈合前期有着不同的影响。失周围神经支配对骨折修复有一定的加速作用, 而脊髓损伤则延缓了骨折前期愈合, 其发生机理仍需进一步研究。

Objective: To investigate the impact of different kinds of nerve injuries on early-stage fracture healing.Method: Three groups of rats were included in the experiment among which group 1 was inflicted with femoral fracture and T10 spinal cord transsection(SCI), group 2 was inflicted with femoral and peripheral nerve resection(PNR), and group 3 with simple femoral fracture as control group. Two weeks after operation the femoral bones were collected for X-ray checking and 2 more weeks later X-ray checking was performed again followed by pathomorphologic exams. Result: X-ray result showed no massive calluses in the bones in the 2nd week postoperatively, while in the 4th week, callus appeared with larger size in group 3 than that of group 1 and with smaller size than that of group 2. It was the same with the result of pathomorphologic examing. Cortical bone bridges between fracture point and osteiod were also found in group 2 and there were less normal blood vessels and worse bone remodeling than that of group 3. There were relatively immature calluses with more fibroblast-like cells and disordered bone structure in group 2. Group 3 showed normal healing process and callus structure.Conclusion:Early-stage bone fracture healing can be influenced significantly by different kinds of nerve injuries.