Stress-concentrating effect of resorption lacunae in trabecular bone
Stress-concentrating effect of resorption lacunae in trabecular bone
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DOI：
10.1016/j.jbiomech.2004.12.027
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发表时间：
2006-01-01
影响因子：
2.4
通讯作者：
Prendergast, PJ
中科院分区：
文献类型：
--
作者：
McNamara, LM;Van der Linden, JC;Prendergast, PJ
单个骨小梁内的应力和应变分布的分析尚未报道。在这项研究中，四个小梁成像和有限元模型，试图量化的变化，应力/应变在真实的小梁。在其中三个小梁中，发现空腔的深度与吸收陷窝报告的值相当（类似于50 μ m）--尽管我们不能确定，但它们很可能确实是吸收陷窝。对每个小梁施加拉伸载荷，以模拟生理载荷并确保弯曲最小化。通过使用每个小梁的平均横截面积从该值计算每个小梁所承载的力。分析预测骨小梁组织内存在非常高的应力（> 100 MPa）。应力和应变分布是高度异质性的，在所有情况下，尤其是在骨小梁与假定的吸收陷窝，其中至少30%的组织的应变大于400 μ m。应力在陷窝凹坑处升高，峰值应力集中位于陷窝前方的纵向方向。考虑到这些高应变，我们认为骨小梁中吸收陷窝周围的微损伤是不可避免的，并且可能导致骨多细胞单位继续吸收骨小梁中的骨包，而不仅仅是吸收最初靶向的任何局部区域。(c)2005爱思唯尔有限公司保留所有权利。
Analyses of the distributions of stress and strain within individual bone trabeculae have not yet been reported. In this study, four trabeculae were imaged and finite elements models were generated in an attempt to quantify the variability of stress/strain in real trabeculae. In three of these trabeculae, cavities were identified with depths comparable to values reported for resorption lacunae (similar to 50 mu m)-although we cannot be certain, it is most probable that they are indeed resorption lacunae. A tensile load was applied to each trabeculum to simulate physiological loading and to ensure that bending was minimized. The force carried by each trabecula was calculated from this value using the average cross sectional area of each trabecula. The analyses predict that very high stresses (> 100 MPa) existed within bone trabecular tissue. Stress and strain distributions were highly heterogeneous in all cases, more so in trabeculae with the presumptive resorption lacunae where at least 30% of the tissue had a strain greater than 400 mu epsilon in all cases. Stresses were elevated at the pit of the lacunae, and peak stress concentrations were located in the longitudinal direction ahead of the lacunae. Given these high strains, we suggest that microdamage is inevitable around resorption lacunae in trabecular bone, and may cause the bone multicellular unit to proceed to resorb a packet of bone in the trabeculum rather than just resorb whatever localized area was initially targeted. (c) 2005 Elsevier Ltd. All rights reserved.