兔肩袖损伤后手术配合TGF-β_1应用对腱-骨愈合过程中生物力学的改变

Biomechanics Response to TGF-β_1 of Tendon-Bone Healing During Early Rat Rotator Cuff Tears

目的评价转化生长因子β1(TGF-β1)对Wistar兔肩袖损伤重建术后早期腱-骨界面愈合的修复效果。方法 8月龄健康雄性新西兰大白兔54只,取双侧肩袖,大结节止点处横断撕裂肩袖冈上肌腱全层,重建肩袖止点原位缝合(双排固定法),腱骨界面注射纤维蛋白胶(FG)为载体的TGF-β1缓释体诱导成骨,造模成功。随机分为高剂量组、低剂量组和单纯手术空白组(空白组)。术后1、2、3周随机分组处死动物,取肩袖标本肉眼观察后行腱-骨界面最大横断面面积、最大抗拉强度及刚度等生物力学测试。结果三组之间无显著性差异。高剂量组最大抗拉强度、刚度及最大横断面面积与低剂量组和空白组比较有显著差异(P<0.05)。低剂量组最大横断面面积及刚度与空白组比较有显著差异(P<0.05)。表明高剂量组在肩袖损伤修复早期效果较佳,腱-骨界面的抗拉强度及刚度随着康复时间的延长而不断增强;而低剂量组可以起肌腱修复作用。结论 TGF-β1能够加强腱-骨界面的最大抗拉强度、刚度及腱-骨修复界面的最大横断面面积,诱导断面再生成直接止点的复杂结构促进肩袖损伤的愈合。在临床有一定的应用价值。

Objective To identify the relationship between the evaluation of tendon-bone healing biomechanical testing and effect of transforming growth factor-β1（TGF-β1） on rotator cuff tears early reconstructive. Methods A total of 54 cases of healthy male New Zealand white rabbits about 8-month old were randomly divided into three groups equally： high-dose, low-dose, control group. All cases were established modeling with full thickness leisure and reconstructive surgery rotator cuff foot-print by suture-bridge and injected TGF-β1released osteogenesis induced by fibrin glue at the tendon bone interface. We had tested the tendon-bone interface biomechanics after the rabbits were randomly batches sacrificed such as tensile strength, cross-section area, stiffness, percentage of loading. Results There was no significant difference among the three groups visually observation accompany the fracture point within the tendon suture. The maximum tensile strength, maximum load percentage, stiffness and tendon bone repair interface of high-dose group were higher than those of the low-dose group and the control group（P 0.05）. The maximum axial loading, tensile strength and stiffness of the tendon-bone interface of low-dose group were significantly higher than those of the control group so that the difference was statistically significant（P 0.05）. The results showed that high-dose group had renovated the tendon-bone interface healing early of rotator cuff injury and stiffness increasing with the extension of the rehabilitation. On the contrary low-dose group could play a role in the later period repairing. Conclusions TGF-β1has strengthened the maximum tensile strength of the tendon-bone. The results suggest that it is worth of promoting in the clinical practice of rotator cuff tears.