Bousson Valérie, Peyrin Françoise, Bergot Catherine, Hausard Marc, Sautet Alain, Laredo Jean-Denis
Laboratoire de Radiologie Expérimentale, Faculté de Médecine Lariboisière-Saint Louis, Paris, France.
J Bone Miner Res. 2004 May;19(5):794-801. doi: 10.1359/JBMR.040124. Epub 2004 Jan 19.
A high-resolution CT system using synchrotron radiation allowed visualization of the 3D cortical bone microarchitecture and measurement of intracortical porosity of femoral neck cortical bone specimens from 19 female cadavers imaged at 10.13-microm resolution. 3D reconstruction of specimens showed osteonal system arrangement. Mean porosity was 15.88%. This technique will provide insights into the mechanisms involved in osteoporotic hip fractures.
The purpose of this study was to show that a high-resolution CT system using synchrotron radiation (SR) allows visualization of the 3D cortical bone microarchitecture of the human femoral neck and quantification of intracortical porosity.
Bone specimens from the inferior femoral neck were obtained from 19 female cadavers with no hip fracture (mean, 86.9 +/- 8.3 years). The specimens, consisting of embedded approximately 7 x 7 x 12-mm cortical bone parallelepipeds, were imaged using SR at 10.13-microm resolution. Commercial software was used to visualize both the 660 x 660 x 660-voxel volumes and the 2D axial slices through each volume. Qualitative examination of 2D axial slices focused on the appearance of the vessel canal system, presence of small bright zones (fully mineralized tissue) in the osseous matrix, and presence of cracks. A method was developed to automatically measure 3D intracortical porosity after separating pure bone from pores and cortical bone from trabecular bone.
3D reconstruction of the specimens showed the entire structure and arrangement of the osteonal systems, parallel to the axis of the femoral neck. Bright zones were seen in the outer cortex. No cracks were observed. Porosity values varied widely from 4.96% to 38.87% (mean, 15.88 +/- 9.87%). This study establishes that SR microtomography can be used to display the 3D bone microstructure of the human femoral neck cortex and to quantify intracortical porosity. This technique will provide insights into the mechanisms involved in cortical bone loss and osteoporotic hip fractures.
一个使用同步辐射的高分辨率CT系统能够对19具女性尸体的股骨颈皮质骨标本的三维皮质骨微结构进行可视化，并测量其皮质内孔隙率，这些标本以10.13微米的分辨率成像。标本的三维重建显示了骨单位系统的排列。平均孔隙率为15.88%。这项技术将为深入了解骨质疏松性髋部骨折的发病机制提供线索。
本研究的目的是证明使用同步辐射（SR）的高分辨率CT系统能够对人类股骨颈的三维皮质骨微结构进行可视化，并对皮质内孔隙率进行量化。
从19具无髋部骨折的女性尸体（平均年龄86.9±8.3岁）获取股骨颈下部的骨标本。这些标本由嵌入的约7×7×12毫米皮质骨平行六面体组成，使用SR以10.13微米的分辨率进行成像。使用商业软件对660×660×660体素体积以及穿过每个体积的二维轴向切片进行可视化。对二维轴向切片的定性检查重点关注血管管系统的外观、骨基质中是否存在小的亮区（完全矿化组织）以及是否存在裂缝。开发了一种方法，在将纯骨与孔隙分离、皮质骨与小梁骨分离后自动测量三维皮质内孔隙率。
标本的三维重建显示了与股骨颈轴线平行的骨单位系统的整体结构和排列。在外皮质可见亮区。未观察到裂缝。孔隙率值差异很大，从4.96%到38.87%（平均为15.88±9.87%）。本研究证实，SR显微断层扫描可用于显示人类股骨颈皮质的三维骨微结构并量化皮质内孔隙率。这项技术将为深入了解皮质骨丢失和骨质疏松性髋部骨折的发病机制提供线索。
