Use of microindentation to characterize the mechanical properties of articular cartilage: comparison of biphasic material properties across length scales.
Use of microindentation to characterize the mechanical properties of articular cartilage: comparison of biphasic material properties across length scales.
复制标题
使用微压痕表征关节软骨的机械性能：跨长度尺度的双相材料性能比较。
DOI：
10.1016/j.joca.2010.04.007
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发表时间：
2010
影响因子：
7
通讯作者：
Morgan,EF
中科院分区：
文献类型：
--
作者：
Miller,GJ;Morgan,EF
目的：小尺度力学测试技术为定义伴随骨关节炎（OA）形态学、组织学和生化异常的力学特性变化提供了新的可能性。本研究的目的是研究微压痕在表征关节软骨双相材料特性中的应用。用微压痕测定的双相性能（E， k和ν）与用标准宏观测试技术测定的双相性能进行了直接比较。方法对10例牛关节软骨深层标本进行大尺度约束和无约束压缩实验。对于微压痕测试，通过对不同双相性能值组合的微压痕实验进行有限元模拟，确定与每个微压痕曲线最匹配的组合，从而确定双相性能。采用配对t检验比较宏观和微观尺度的E、k和ν。结果E、k和ν的微尺度值分别为0.74(0.53、0.95)MPa、0.66（0.022、0.110）×10−16m4/Ns和0.16（0.08、0.24）。在宏观和微观尺度上，k的测量值有显著差异（P<0.0001），但E或ν没有显著差异（P=0.88, 0.16）。结论微压痕与宏观测试结果在杨氏模量和泊松比上的一致性支持微压痕用于表征关节软骨的某些双相材料特性。观察到的渗透率在宏观和微观尺度之间的差异与文献中关于长度尺度依赖于这一性质的证据一致。
OBJECTIVESmall scale mechanical testing techniques offer new possibilities for defining changes in mechanical properties that accompany the morphological, histological, and biochemical abnormalities of osteoarthritis (OA). The goal of this study was to investigate the use of microindentation in characterizing the biphasic material properties of articular cartilage. Direct comparisons of the biphasic properties (E, k and ν) determined using microindentation were made to those determined on the same specimens using standard macroscale testing techniques.METHODSDeep-zone bovine articular cartilage specimens (n=10) were tested in macroscale confined and unconfined compression. For microindentation testing, the biphasic properties were determined by conducting finite element simulations of the microindentation experiments for different combinations of values of biphasic properties and identifying the combination yielding the best match to each microindentation curve. Paired t-tests were performed to compare each of E, k and ν between the macro- and microscale.RESULTSThe microscale values for E, k and ν were 0.74 (0.53, 0.95)MPa, 0.66 (0.022, 0.110)×10−16m4/Ns, and 0.16 (0.08, 0.24), respectively. A significant difference between the macro- and microscale measurements was observed for k (P<0.0001), but not for E or ν (P=0.88, 0.16).CONCLUSIONSThe agreement in Young’s modulus and Poisson’s ratio between the results of the microindentation and macroscale tests supports the use of microindentation for characterization of some of the biphasic material properties of articular cartilage. The observed differences in permeability between macro- and microscales are consistent with evidence in the literature of a length-scale dependence to this property.