Portero-Muzy Nathalie R, Chavassieux Pascale M, Mitton David, Duboeuf François, Delmas Pierre D, Meunier Pierre J
INSERM Unité 831, Faculté de Médecine Laennec, Université de Lyon, 69372, Lyon Cedex 08, France.
Calcif Tissue Int. 2007 Aug;81(2):92-8. doi: 10.1007/s00223-007-9044-y. Epub 2007 Jul 18.
The amount of bone and the trabecular microarchitecture are two determinants of bone strength which can be quantified by bone histomorphometry. Among the parameters of bone microarchitecture, the Euler number developed in our laboratory (E( strut.cavity )) and trabecular bone pattern factor (TBPf) evaluate the connectivity and complexity independently of the bone quantity, and the speed of sound (SOS) measured by quantitative ultrasound (QUS) corroborates E( strut.cavity ). The aim of the present study was to validate E( strut.cavity ), TBPf, and SOS as parameters of bone microarchitecture and their contribution to bone strength. We examined 20 right os calcis taken after necropsy in 11 males and 9 females, aged 52-95 years. At the same anatomic location, we measured SOS and broadband ultrasound attenuation (BUA) using a Hologic Sahara device and bone mineral density (BMD) using a Hologic QDR 1000W. At this site a transcortical cylinder was cut for both apparent density measurement (Ap.Dens) and biomechanical tests (maximum compressive stress (sigma(max)) and Young's modulus (E)), and histomorphometry was performed with an automatic image analyzer (Visiolab, Explora Nova, France). E and sigma(max) were significantly correlated with the parameters of bone quantity, microarchitecture, and QUS. However, after adjustment for the bone quantity, E correlated only with E( strut.cavity ), TBPf, and SOS, and sigma(max) with BUA. In conclusion, the bone connectivity and complexity evaluated by E( strut.cavity ) and TBPf contribute to bone strength, independently of the bone quantity. The bone mechanical properties may be assessed, in os calcis, in the elastic domain by SOS and in the plastic domain by BUA.
骨量和小梁微结构是骨强度的两个决定因素，可通过骨组织形态计量学进行量化。在骨微结构参数中，我们实验室开发的欧拉数（E(支柱.腔)）和小梁骨模式因子（TBPf）可独立于骨量评估连通性和复杂性，而通过定量超声（QUS）测量的声速（SOS）则证实了E(支柱.腔)。本研究的目的是验证E(支柱.腔)、TBPf和SOS作为骨微结构参数及其对骨强度的贡献。我们检查了11名男性和9名女性死后取出的20个右侧跟骨，年龄在52 - 95岁之间。在相同的解剖位置，我们使用Hologic Sahara设备测量SOS和宽带超声衰减（BUA），并使用Hologic QDR 1000W测量骨矿物质密度（BMD）。在该部位切取一个经皮质圆柱体用于表观密度测量（Ap.Dens）和生物力学测试（最大压缩应力（sigma(max)）和杨氏模量（E）），并使用自动图像分析仪（Visiolab，Explora Nova，法国）进行组织形态计量学分析。E和sigma(max)与骨量、微结构和QUS参数显著相关。然而，在对骨量进行调整后，E仅与E(支柱.腔)、TBPf和SOS相关，而sigma(max)与BUA相关。总之，由E(支柱.腔)和TBPf评估的骨连通性和复杂性对骨强度有贡献，且独立于骨量。在跟骨中，骨力学性能在弹性域可通过SOS评估，在塑性域可通过BUA评估。
