体内移植羊膜对家兔肌腱损伤模型肌腱愈合的影响

研究的目的在于观察羊膜体内移植对肌腱损伤修复的影响。60 只跟腱损伤家兔动物模型采用同体对照动物实验方法，大体观察伤口愈合、肌腱粘连及肌腱肥大情况，并分别于术后第 2、4、6 周等3个时间点取跟腱，HE染色观察损伤区域炎细胞浸润和成纤维细胞数量，免疫组化染色观察胶原纤维排列塑形状况，拉伸试验测定肌腱弹性模量。另取 4 只家兔不做肌腱切断术作为正常对照，在第 0周 测定肌腱弹性模量。全部实验动物皮肤切口在术后 1 周 内基本愈合，未发生伤口感染情况。羊膜实验组跟腱粘连动物数量和肌腱断裂区域肥大程度低于阴性对照组(P<0.05)。术后第 2 周，两组动物炎症反应均达到最高值，但羊膜实验组炎细胞（包括中性粒细胞和单核细胞）浸润数量低于阴性对照组(P<0.05)。两组实验动物样本中成纤维细胞数量和胶原纤维积累数量无明显差异（P >0.05），但羊膜实验组成纤维细胞和胶原纤维排列更具有序性，尤其是在术后第 6 周，明显好于阴性对照组。术后第 2 周和第4 周，羊膜实验组肌腱弹性模量均优于阴性对照组(P <0.05)。羊膜具有促进肌腱早期愈合和抗炎、抗粘连作用。

The Effect of Amniotic Membrane Transplantation on Tendon Healing in a Rabbit Achilles Tendon Experimental Model

The present study investigated the healing effect of amniotic membrane (AM) as a biological extracellular matrix scaffold on broken achilles tendon in a rabbit model．Sixty rabbits were allocated to histological evaluations at two, four, and six weeks and to biomechanical studies at the same time points. Hindlimbs of both sides were conducted surgery, one of the hindlimbs was taken as a control for the other．For AM group, the laceration site was wrapped with amniotic membrane. The wound healing, peritendinous adhesion and cross sectional areas of the laceration sites between two groups were examined. Histological evaluation of inflammatory cells and fibroblasts was performed using hematoxylin and eosin staining technique, immunohistochemical staining for collagen type I and III was conducted as well. Tensile strength of the tendons was tested and modulus of the tendons was calculated．Modulus of hindlimbs for four naive rabbits was tested at the beginning of the experiments and taken as a common control. There was no a wound infected with germs and the wound of all animals healed in one week. There was significant difference in peritendinous adhesion and the cross sectional areas of the laceration sites between the two groups (P<0.05). The peritendinous adhesion and the cross sectional areas of the laceration sites were significantly lower in the AM treatment group. The inflammatory response was the most apparent at two weeks in both groups, but the cellularity of inflammatory cells at two weeks was significantly lower in the AM treatment group (P <0.05), including neutrophils，mononuclear cells and total cell count．There was no definitive difference in the amount of fibroblasts and collagen between the two groups (P>0.05). The structures of collagen type I and III were more organized in the AM treatment group, especially at six weeks post the surgery. The modulus of the tendons were significantly higher in the AM treatment group (P <0.05)  at two and four weeks. In conclusion, the amniotic membrane enhanced maturation of the histological organization of the fibroblasts and collagen fibers, improved the material property of the lacerated tendons, restrained inflammatory response and peritendinous adhesion in the early healing period．