LEMTA, Group of Bioengineering, Nancy-Université, CNRS UMR 7563, 2 avenue de la Forêt de Haye, 54504 Vandœuvre-lès-Nancy, France.
J Mech Behav Biomed Mater. 2012 Aug;12:184-96. doi: 10.1016/j.jmbbm.2012.03.005. Epub 2012 Mar 24.
An adapted scaffold for Anterior Cruciate Ligament (ACL) tissue engineering must match biological, morphological and biomechanical requirements. Computer-aided tissue engineering consists of finding the most appropriate scaffold regarding a specific application by using numerical tools. In the present study, the biomechanical behavior of a new multilayer braided scaffold adapted to computer-aided tissue engineering is computed by using a dedicated Finite Element (FE) code. Among different copoly(lactic acid-co-(ε-caprolactone)) (PLCL) fibers tested in the present study, PLCL fibers with a lactic acid/ε-caprolactone ratio of 85/15 were selected as a constitutive material for the scaffold considering its strength and deformability. The mechanical behavior of these fibers was utilized as material input in a Finite Element (FE) code which considers contact/friction interactions between fibers within a large deformation framework. An initial geometry issued from the braiding process was then computed and was found to be representative of the actual scaffold geometry. Comparisons between simulated tensile tests and experimental data show that the method enables to predict the tensile response of the multilayer braided scaffold as a function of different process parameters. As a result, the present approach constitutes a valuable tool in order to determine the configuration which best fits the biomechanical requirements needed to restore the knee function during the rehabilitation period. The developed approach also allows the mechanical stimuli due to external loading to be quantified, and will be used to perform further mechanobiological analyses of the scaffold under dynamic culture.
用于前交叉韧带(ACL)组织工程的改良支架必须满足生物、形态和生物力学要求。计算机辅助组织工程包括通过使用数值工具找到与特定应用最匹配的支架。在本研究中,通过使用专用的有限元(FE)代码计算了适应计算机辅助组织工程的新型多层编织支架的生物力学行为。在本研究中测试的不同共聚(乳酸-co-(ε-己内酯))(PLCL)纤维中,考虑到支架的强度和可变形性,选择乳酸/ε-己内酯比为 85/15 的 PLCL 纤维作为支架的本构材料。这些纤维的机械性能被用作纤维在大变形框架内的接触/摩擦相互作用的有限元(FE)代码中的材料输入。然后计算出初始的编织工艺几何形状,并发现它代表了实际支架的几何形状。模拟拉伸试验与实验数据的比较表明,该方法能够预测多层编织支架的拉伸响应,作为不同工艺参数的函数。因此,本方法为确定在康复期间恢复膝关节功能所需的最佳生物力学要求的配置提供了有价值的工具。所开发的方法还允许对外加载荷产生的机械刺激进行量化,并将用于在动态培养下对支架进行进一步的力学生物学分析。