血管束、感觉神经束植入组织工程骨修复大段骨缺损的成骨研究

Osteogenesis of tissue-engineered bone implanted with grafts of vascular and sensory nerve bundles

目的观察血管束、感觉神经束植入组织工程骨修复兔股骨大段骨缺损的成骨特点，探讨其对骨修复的影响。方法36只新西兰大白兔均制备左侧股骨干1．5cm节段性骨缺损模型，随机分为三组（n=12），组织工程骨组（A组）：自体骨髓基质干细胞复合β-磷酸三钙构建组织工程骨植入骨缺损；血管束植入组（B组）：组织工程骨与血管束同时植入骨缺损；感觉神经束植人组（C组）：组织工程骨与感觉神经束同时植入骨缺损。各组动物术后1、3、6个月行X线检查及影像学评分，同时每组各处死4只动物行大体及组织学观察。结果影像学评分显示各时间点B组与C组的成骨优于A组，差异有统计学意义（P〈0．05）；B、C组间成骨差异无统计学意义（P〉0．05）。组织学观察显示新生骨多出现在血管周围，成骨方式以软骨内成骨为主。结论血管束、感觉神经束植入组织工程骨的方法能更好地促进组织工程骨成骨及大段骨缺损修复。

Objective To investigate the osteogenesis of the tissue-engineered bone implanted with grafts of vascular and sensory nerve bundles. Methods Models of left femoral defects of 1.5 cm were fabricated in 36 New Zealand white rabbits which were randomized into 3 groups. In Group A, the tissue-engineered bone which had been constructed with autologous bone marrow mesenchymal stem cells plus β-tricalcium phosphate （β-TCP） was implanted into the defects. In group B, the tissue-engineered bone plus graft of vascular bundle was implanted into the femoral defects. In group C, the tissue-engineered bone plus graft of sensory nerve bundle was implanted into the bony defects. Bone formation throughout the defects was assessed radiographically 1, 3 and 6 months after implantation, and at the same time 4 rabbits from each group were sacrificed to evaluate bone formation by gross and histological observations. Results The bone formation in groups B and C was better than in group A （ P 〈 0. 05）, but there was no significant difference between groups B and C （ P 〉0. 05 ）. New bone formation occurred mostly around the vessels and chiefly in the form of enchondral ossification. Conclusion hnplantation of vascular and sensory nerve bundles into tissue-engineered bone may enhance the osteogenesis of tissue-engineered bone in reconstruction of large bony defects.