The anisotropy of osteonal bone and its ultrastructural implications.
The anisotropy of osteonal bone and its ultrastructural implications.
复制标题
骨的各向异性及其超微结构的影响。
DOI：
10.1016/8756-3282(95)00148-7
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发表时间：
1995
期刊：
影响因子：
4.1
通讯作者：
Pidaparti,RM
中科院分区：
文献类型：
--
作者：
Turner,CH;Chandran,A;Pidaparti,RM
骨的各向异性弹性对称性反映了骨内胶原原纤维和矿物晶体的超微结构组织以及层状微观结构。直到最近，由于测量技术的精度和分辨率较差，报道的骨各向异性弹性特性的值在解释上受到限制。在这里，我们报告使用高精度声学显微镜测量骨各向异性。取23根股骨，以距骨长轴10°的增量测量犬股骨标本的弹性特性。一半的骨标本随后在EDTA溶液中脱矿，另一半在次氯酸钠溶液中脱矿，并重复声学测量。我们发现骨的弹性对称性明显偏离了支持板层微观结构形成“旋转胶合板”假设的正交各向异性理论（Weiner和Traub， FASEB J:879 - 885; 1992）。骨矿物的主要取向是沿骨长轴排列，而骨胶原似乎与骨长轴成30°角排列。矿物质和胶原蛋白之间的错位表明：(1)相当大比例的矿物质是纤维外的，(2)纤维外矿物质的排列受外部影响，例如机械应力。
The anisotropic elastic symmetry of osteonal bone reflects the ultrastructural organization of collagen fibrils and mineral crystals within the osteons as well as the lamellar microstructure. Until recently, reported values for bone's anisotropic elastic properties were limited in their interpretation by poor precision and resolution of measurement techniques. Here, we report measurements of bone anisotropy using high precision acoustic microscopy. The elastic properties of canine femoral bone specimens, taken from 23 femora, were measured at 10° increments from the long axis of the bone. Half of the bone specimens subsequently were demineralized in EDTA solution, the other half were decollagenized in sodium hypochlorite solution, and the acoustic measurements were repeated. We found the elastic symmetry of osteonal bone deviates significantly from orthotropic theory supporting the hypothesis that the lamellar microstructure forms a “rotated plywood” (Weiner and Traub, FASEB J 6:879–885; 1992). The principal orientation of bone mineral was along the long axis of the bone, while bone collagen appeared to be aligned at a 30° angle to the long axis. The misalignment between the mineral and the collagen suggests that (1) a substantial percentage of the mineral is extrafibrillar, and (2) the alignment of extrafibrillar mineral is governed by external influences, e.g., mechanical stresses.