腱周组织包绕对重建后交叉韧带移植物组织学及血管内皮因子的影响

摘要

目的:研究腱周组织包绕后交叉韧带(PCL)移植物对移植物组织学及血管内皮因子(VEGF)水平的影响.方法:选取24只比格犬,行双后肢PCL切断,取同侧拇长屈肌腱重建,在每只犬双后肢中,取其中之一后肢用跟腱腱周组织包绕拇长屈肌腱重建作为实验组,对侧不做包绕作为对照组,术后4周、8周、12周各取8只犬双侧后肢重建移植物,进行组织学观察.结果:实验组术后4周,韧带外有肉芽组织包绕,血运丰富,移植物有大量纤维细胞增殖.术后8周,滑膜形成,韧带近似正常后交叉韧带.术后12周,移植物外包绕滑膜变薄,显微镜下见重建韧带纤维细胞核变杆状、纺锤体状,排列规律,与正常PCL相同;对照组血管化明显滞后,术后4周,两组移植物VEGF免疫组化平均光密度值比较,差异有统计学意义(P≥0.05),且木后8周、12周两组差异更为显著(P≥0.01).结论:使用跟腱腱周组织包绕自体移植物进行PCL重建能有效增加移植物中VEGF水平和相应的血管生成,加快再血管化进程,为纤维细胞迁移、生长、增殖提供条件.%Objective:To investigate the histological changes of autograft and vascular endothelial growth factor(VEGF) level after posterior cruciate ligament (PCL) reconstruction using flexor hallucis longus (FHL) tendons wrapping with peritendon tissues.Methods:PCL was reconstructed with FHL wrapping the peritendon tissues of Achilles tendons in 24 Beagle dogs(experimental group) and with simple tendon autograft(control group).After 4,8 and 12 weeks,the histological changes of autograft were observed,and VEGF protein expression was detected by immunohistochemistry.Results:In the experimental group,the grafted tendons were surrounded by granulation tissues with abundant blood vessels and a large number of fibroblasts around at 4 weeks post-operation.After 8 weeks,the synovium formed and the ligaments were similar to the normal PCL.At week 12,the synovium around the grafts became thinner.Under the microscope,the fibrocyte nuclei in the grafted ligaments gradually became rod-like and spindle-like shapes and well-organized,which was the same as the normal PCL.In comparison,these changes in the control group were much slower.There was a significant difference in the average optical density of VEGF between the two groups at 4 weeks post-operation(P＜0.05),and the changes were more significant at week 8 and 12(P ＜0.01).Conclusion:Application of the additional peritendon tissues of Achilles tendons wrapping autograft in PCL reconstruction could enhance VEGF level,facilitate vascularization,and promote fibrocyte migration and proliferation in grafts.