INSERM Research Unit 831 and Université de Lyon, Lyon, France.
J Bone Miner Res. 2011 May;26(5):965-73. doi: 10.1002/jbmr.297.
Few studies have investigated bone microarchitecture and biomechanical properties in men. This study assessed in vivo both aspects in a population of 185 men (aged 71 ± 10 years) with prevalent fragility fractures, compared to 185 controls matched for age, height, and weight, from the Structure of the Aging Men's Bones (STRAMBO) cohort. In this case-control study, areal BMD (aBMD) was measured by DXA, bone microarchitecture was assessed by high resolution (HR)-pQCT, and finite element (µFE) analysis was based on HR-pQCT images of distal radius and tibia. A principal component (PC) analysis (PCA) was used to study the association of synthetic PCs with fracture by computing their odds ratio (OR [95%CI]) per SD change. Specific associations with vertebral fracture (n = 100), and nonvertebral fracture (n = 85) were also computed. At both sites, areal and volumetric BMD, cortical thickness and trabecular number, separation, and distribution were significantly worse in cases than in controls, with differences ranging from -6% to 15%. µFE-derived stiffness and failure load were 8% to 9% lower in fractures (p < .01). No difference in load distribution was found between the two groups. After adjustment for aBMD, only differences of µFE-derived stresses, stiffness, and failure load at the tibia remained significant (p < .05). PCA resulted in defining 4 independent PCs, explaining 83% of the total variability of bone characteristics. Nonvertebral fractures were associated with PC1, reflecting bone quantity and strength at the radius (tibia) with OR = 1.64 [1.27-2.12] (2.21 [1.60-3.04]), and with PC2, defined by trabecular microarchitecture, with OR = 1.27 [1.00-1.61]. Severe vertebral fractures were associated with PC1, with OR = 1.56 [1.16-2.09] (2.21 [1.59-3.07]), and with PC2, with OR = 1.55 [1.17-2.06] (1.45 [1.06-1.98]). In conclusion, microarchitecture and biomechanical properties derived from µFE were associated with all types of fractures in men, showing that radius and tibia mechanical properties were relatively representative of distant bone site properties.
很少有研究调查男性的骨微观结构和生物力学特性。本研究评估了 185 名患有常见脆性骨折的男性（年龄 71±10 岁）和 185 名年龄、身高和体重匹配的对照组的这两个方面，这些男性来自结构老龄化男性骨骼（STRAMBO）队列。在这项病例对照研究中，通过 DXA 测量面积骨密度（aBMD），通过高分辨率（HR）-pQCT 评估骨微观结构，基于 HR-pQCT 图像进行有限元（µFE）分析远端桡骨和胫骨。使用主成分（PC）分析（PCA）通过计算每个标准差变化的优势比（OR [95%CI]）来研究综合 PCs 与骨折的关联。还计算了与椎体骨折（n=100）和非椎体骨折（n=85）的特定关联。在两个部位，病例组的面积和体积 BMD、皮质厚度和小梁数量、分离和分布均明显低于对照组，差异范围为-6%至 15%。µFE 衍生的刚度和失效载荷低 8%至 9%（p<.01）。两组之间的负荷分布没有差异。在调整 aBMD 后，只有胫骨的 µFE 衍生的应力、刚度和失效载荷差异仍然显著（p<.05）。PCA 导致定义了 4 个独立的 PCs，解释了骨骼特征总变异性的 83%。非椎体骨折与 PC1 相关，反映了桡骨（胫骨）的骨量和强度（OR=1.64[1.27-2.12]（2.21[1.60-3.04]）），以及与 PC2 相关，由小梁微观结构定义，OR=1.27[1.00-1.61]。严重的椎体骨折与 PC1 相关，OR=1.56[1.16-2.09]（2.21[1.59-3.07]），与 PC2 相关，OR=1.55[1.17-2.06]（1.45[1.06-1.98]）。总之，来自 µFE 的微观结构和生物力学特性与男性的所有类型骨折相关，表明桡骨和胫骨的力学特性相对代表了远处骨骼部位的特性。
