持续被动活动对兔重建前交叉韧带组织学研究的影响

Histological study of the effects of continuous passive motion on remolding of the tendon autograft used for anterior cruciate ligament reconstruction in rabbits

目的:通过兔半腱肌腱腱后固定方法重建前交叉韧带(ACL)实验动物模型,研究持续被动活动方式对关节腔内移植物组织学变化,探讨膝关节持续被动活动(CPM)在ACL重建术后早期康复中的作用。方法:对24只8月龄雄性新西兰大白兔右侧后肢膝关节行自体双股半腱肌腱移植重建前交叉韧带手术。术后随机分为2组:CPM组术后第2天开始早期关节全活动范围康复6周;非CPM组仅笼养。分别于术后第6、12、24周取材,取4只行组织学观察。结果:与非CPM组相比,CPM组的大部分标本两束融合成一体。术后第6周,CPM组的关节腔内重建韧带的新生组织替代过程加快,增生的细胞数目较多;术后第12周,CPM组的细胞形状较统一,胶原纤维纵向排列更为有序,呈波状,较广泛的组织呈Ⅰ型胶原阳性,组织内部Ⅲ型胶原更为均匀;术后第24周,CPM组胶原排列更为有序,成纤维细胞梭形的细胞核也逐渐变为标志成熟韧带的长形,Ⅰ型胶原染色更为均匀散在分布,Ⅲ型胶原明显减少。结论:半腱肌腱重建前交叉韧带术后早期CPM促进移植物韧带化。

Objective： To study the effects of continuous passive motion （CPM） on the histology of the semitendinous tendon autograft used for anterior cruciate ligament （ACL） reconstruction in rabbits. Method： In 24 8-months-old male rabbits, ACL reconstruction were performed by using double semitendinous tendon autograft. Postoperatively these animals were treated by either continuous passive motion or cage activity （non- CPM）. All of the knees, including the contralateral controls, had gross and histologic examination,immunohistochemical examination for collagen content at 6th, 12th and 24th week postoperatively. Result： CPM specimens showed a more fuse rate. At 6th week the new born tissue grew into the graft from peripheral areas,the grafts demonstrated increased cellularity and irregular organization of collagen bundles. At 12th week cell number decreased and collagen fiber bundles showed more regular longitudinal orientation. At 24th week the histomorphologic appearance was similar to that of normal ACL. Although the remodeling progress was similar, the tissue was more mature and structured in the CPM, furthermore, more type Ⅰ collagen and less type Ⅲ collagen were found. Conclusion： CPM enhances the nutrition and metabolic activity of ligament, decreases graft-tunnel motion, accelerates remodeling and healing of tendons and ligaments. According to this point, early CPM after the reconstruction with semitendinous tendon would be good for the reshaping and restructuring of the graft.