Kroker Andres, Zhu Ying, Manske Sarah L, Barber Rhamona, Mohtadi Nicholas, Boyd Steven K
Department of Radiology, Cumming School of Medicine, University of Calgary, Canada; McCaig Institute for Bone and Joint Health, University of Calgary, Canada.
University of Calgary Sport Medicine Centre, University of Calgary, Canada.
Bone. 2017 Apr;97:43-48. doi: 10.1016/j.bone.2016.12.015. Epub 2016 Dec 27.
High-resolution peripheral quantitative computed tomography (HR-pQCT) is a novel imaging modality capable of visualizing bone microarchitecture in vivo at human peripheral sites such as the distal radius and distal tibia. This research has extended the technology to provide a non-invasive assessment of bone microarchitecture at the human knee by establishing new hardware, imaging protocols and data analysis.
A custom leg holder was developed to stabilize a human knee centrally within a second generation HR-pQCT field of view. Five participants with anterior cruciate ligament reconstructions had their knee joint imaged in a continuous scan of 6cm axially. The nominal isotropic voxel size was 60.7μm. Bone mineral density and microarchitecture were assessed within the weight-bearing regions of medial and lateral compartments of the knee at three depths from the weight-bearing articular bone surface, including both the cortical and trabecular bone regions.
Scan duration was approximately 18min per knee and produced 5GB of projection data and 10GB of reconstructed image data (2304×2304 image matrix, 1008 slices). Motion during the scan was minimized by the leg holder and was similar in magnitude as a scan of the distal tibia. Bone mineral density and microarchitectural parameters were assessed for 16 volumes of interest in the tibiofemoral joint.
This is a new non-invasive in vivo assessment tool for bone microarchitecture in the human knee that provides an opportunity to gain insight into normal, injured and surgically reconstructed human knee bone architecture in cross-sectional or longitudinal studies.
高分辨率外周定量计算机断层扫描（HR-pQCT）是一种新型成像方式，能够在体内可视化人类外周部位（如桡骨远端和胫骨远端）的骨微结构。本研究通过建立新的硬件、成像协议和数据分析，扩展了该技术，以提供对人类膝关节骨微结构的非侵入性评估。
开发了一种定制的腿部固定器，以将人类膝关节稳定在第二代HR-pQCT视野的中心。五名进行了前交叉韧带重建的参与者对其膝关节进行了轴向6厘米的连续扫描成像。标称各向同性体素大小为60.7μm。在膝关节内侧和外侧间室的负重区域内，从负重关节骨表面起的三个深度处评估骨密度和微结构，包括皮质骨和小梁骨区域。
每个膝关节的扫描持续时间约为18分钟，产生5GB的投影数据和10GB的重建图像数据（2304×2304图像矩阵，1008层）。腿部固定器将扫描过程中的运动降至最低，其幅度与胫骨远端的扫描相似。对胫股关节的16个感兴趣区域评估了骨密度和微结构参数。
这是一种用于人类膝关节骨微结构的新型非侵入性体内评估工具，为在横断面或纵向研究中深入了解正常、受伤和手术重建的人类膝关节骨结构提供了机会。
