Qin Tingwu, Zhang Shujiang, Yang Zhiming, Li Xiuqun
Institute of Reparative and Reconstructive Surgery, Department of Orthopedic Surgery, West China Hospital, Sichuan University, Chengdu 610041.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi. 2003 Dec;20(4):601-4.
Experiments have been performed to investigate why the biomechanical strength of repaired tendons is lower than that of the normal tendon when the engineered tendons are implanted in vivo to replace the tendon defects. We seeded the primary culture tendon cells derived from Roman chickens' digital flexor tendons on the degradable polyglycolic acid meshes to construct tissue-engineered tendons. The flexor tendon defects (0.5 cm-0.8 cm) excised in second digit bilaterally in 20 Roman chickens, had been repaired with the constructed tissue-engineered tendons. The samples of repaired tendons were collected at 2, 4, 6 and 8 weeks after operation. Tests for scaffold weight, hydroxyproline content, and mechanical strength of the samples were performed. We found that from 2 weeks to 8 weeks afteroperation, the weight of the scaffolds decreased significantly, almost disappearing at 8 weeks; the hydroxyproline content determining the total collagen content increased gradually without significance; mechanically, both energy at break and tensile strength showed a tendency of drastic decrease at first 4 weeks afteroperation and a gradual increase afterwards, but the tensile strength at 8 weeks afteroperation was only 23% of that of the normal tendon. We conclude that the lower biomechanical strength of repaired tendons is owing to the serious mismatch between scaffold degradation and collagen synthesis.
已经开展了实验来研究当将工程化肌腱植入体内以替代肌腱缺损时，修复后的肌腱生物力学强度为何低于正常肌腱。我们将源自罗曼鸡指屈肌腱的原代培养肌腱细胞接种于可降解聚乙醇酸网片上，以构建组织工程化肌腱。在20只罗曼鸡双侧第二趾切除0.5厘米至0.8厘米的屈肌腱缺损，并用构建的组织工程化肌腱进行修复。术后2周、4周、6周和8周采集修复肌腱的样本。对样本进行支架重量、羟脯氨酸含量和机械强度测试。我们发现，术后2周 至8周，支架重量显著下降，在8周时几乎消失；决定总胶原蛋白含量的羟脯氨酸含量逐渐增加但无显著性差异；在力学方面，断裂能量和拉伸强度在术后前4周均呈现急剧下降趋势，之后逐渐增加，但术后8周时的拉伸强度仅为正常肌腱的23%。我们得出结论，修复后肌腱生物力学强度较低是由于支架降解与胶原蛋白合成之间严重不匹配所致。
