Zhou Bin, Wang Ji, Yu Y Eric, Zhang Zhendong, Nawathe Shashank, Nishiyama Kyle K, Rosete Fernando Rey, Keaveny Tony M, Shane Elizabeth, Guo X Edward
Bone Bioengineering Laboratory, Department of Biomedical Engineering, Columbia University, New York, NY, U.S.A.
Bone Bioengineering Laboratory, Department of Biomedical Engineering, Columbia University, New York, NY, U.S.A.; Department of Orthopedic Surgery, First Affiliated Hospital, School of Medicine, Shihezi University, Shihezi, Xinjiang, China.
Bone. 2016 May;86:58-67. doi: 10.1016/j.bone.2016.02.016. Epub 2016 Feb 26.
High-resolution peripheral quantitative computed tomography (HR-pQCT) provides in vivo three-dimensional (3D) imaging at the distal radius and tibia and has been increasingly used to characterize cortical and trabecular bone morphology in clinical studies. In this study, we comprehensively examined the accuracy of HR-pQCT and HR-pQCT based micro finite element (μFE) analysis predicted bone elastic stiffness and strength through comparisons with gold-standard micro computed tomography (μCT) based morphological/μFE measures and direct mechanical testing results. Twenty-six sets of human cadaveric distal radius and tibia segments were imaged by HR-pQCT and μCT. Microstructural analyses were performed for the registered HR-pQCT and μCT images. Bone stiffness and yield strength were determined by both HR-pQCT and μCT based linear and nonlinear μFE predictions and mechanical testing. Our results suggested that strong and significant correlations existed between the HR-pQCT standard, model-independent and corresponding μCT measurements. HR-pQCT based nonlinear μFE overestimated stiffness and yield strength while the linear μFE underestimated yield strength, but both were strongly correlated with those predicted by μCT μFE and measured by mechanical testing at both radius and tibia (R(2)>0.9). The microstructural differences between HR-pQCT and μCT were also examined by the Bland-Altman plots. Our results showed HR-pQCT morphological measurements of BV/TV(d), Tb.Th, and Tb.Sp, can be adjusted by correction values to approach true values measured by gold-standard μCT. In addition, we observed moderate correlations of HR-pQCT biomechanical and microstructural parameters between the distal radius and tibia. We concluded that morphological and mechanical properties of human radius and tibia bone can be assessed by HR-pQCT based measures.
高分辨率外周定量计算机断层扫描（HR-pQCT）可对桡骨远端和胫骨进行体内三维（3D）成像，并且在临床研究中越来越多地用于表征皮质骨和小梁骨形态。在本研究中，我们通过与基于金标准微型计算机断层扫描（μCT）的形态学/微有限元（μFE）测量以及直接力学测试结果进行比较，全面检验了HR-pQCT以及基于HR-pQCT的微有限元（μFE）分析预测骨弹性刚度和强度的准确性。对26组人类尸体的桡骨远端和胫骨段进行了HR-pQCT和μCT成像。对配准后的HR-pQCT和μCT图像进行了微观结构分析。通过基于HR-pQCT和μCT的线性和非线性μFE预测以及力学测试来确定骨刚度和屈服强度。我们的结果表明，HR-pQCT标准测量值、与模型无关的测量值以及相应的μCT测量值之间存在强且显著的相关性。基于HR-pQCT的非线性μFE高估了刚度和屈服强度，而线性μFE低估了屈服强度，但二者与通过μCT μFE预测并通过力学测试在桡骨和胫骨处测得的结果均具有高度相关性（R²>0.9）。还通过Bland-Altman图检查了HR-pQCT和μCT之间的微观结构差异。我们的结果表明，HR-pQCT对骨体积分数（BV/TV(d)）、骨小梁厚度（Tb.Th）和骨小梁间距（Tb.Sp）的形态学测量值可通过校正值进行调整，以接近金标准μCT测得的真实值。此外，我们观察到桡骨远端和胫骨之间HR-pQCT生物力学和微观结构参数存在中度相关性。我们得出结论，基于HR-pQCT的测量方法可用于评估人体桡骨和胫骨的形态学和力学特性。
