BACKGROUND Postmenopausal women with isolated osteoporosis at the 1/3 radius (1/3RO) present a therapeutic dilemma. Little is known about whether these patients have generalized skeletal fragility, and whether this finding warrants treatment. The aim of this study was to investigate the biochemical and microarchitectural phenotype of women with 1/3RO compared to women with classic postmenopausal osteoporosis by DXA at the spine and hip (PMO), and controls without osteoporosis at any site. METHODS This cross-sectional study enrolled 266 postmenopausal women, who were grouped according to densitometric pattern. Subjects had serum biochemistries, areal BMD (aBMD) measured by DXA, trabecular and cortical vBMD, microarchitecture, and stiffness by high resolution peripheral QCT (HR-pQCT, voxel size ~82 μm) of the distal radius and tibia. RESULTS Mean age was 68 ± 7 years. DXA T-Scores reflected study design. By HR-pQCT, 1/3RO had abnormalities at both radius and tibia compared to controls: lower total, cortical and trabecular vBMD, cortical thickness and trabecular number, higher trabecular separation and heterogeneity, and lower whole bone stiffness. In contrast, the magnitude and pattern of abnormalities in vBMD, microarchitecture and stiffness in 1/3RO were similar to those in PMO; the difference compared to controls was similar among the two groups. Serum calcium, creatinine, parathyroid hormone, 25-hydroxyvitamin D, and 24-hour urine calcium did not differ. CONCLUSIONS Although aBMD appeared relatively preserved at the spine and hip by DXA, women with 1/3RO had significant microarchitectural and biomechanical deficits comparable to those in women with typical PMO. Further study is required to guide treatment decisions in this population.

中文翻译：

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绝经后女性 1/3 半径处孤立性骨质疏松症的微结构异常和僵硬


背景 患有 1/3 半径 (1/3RO) 孤立性骨质疏松症的绝经后妇女面临着治疗困境。人们对这些患者是否患有全身骨骼脆弱以及这一发现是否值得治疗知之甚少。本研究的目的是通过 DXA 在脊柱和髋部 (PMO) 测定患有 1/3RO 的女性与经典绝经后骨质疏松症女性以及任何部位无骨质疏松症的对照女性的生化和微结构表型。方法 这项横断面研究纳入了 266 名绝经后女性，并根据光密度模式进行分组。受试者通过 DXA 测量面积 BMD (aBMD)、小梁和皮质 vBMD、微结构以及远端桡骨和胫骨的高分辨率外周 QCT（HR-pQCT，体素大小约 82 μm）测量硬度。结果 平均年龄为 68 ± 7 岁。 DXA T 分数反映了研究设计。通过 HR-pQCT，与对照组相比，1/3RO 在桡骨和胫骨均出现异常：总的皮质和小梁 vBMD、皮质厚度和小梁数量较低，小梁分离和异质性较高，整体骨刚度较低。相比之下，1/3RO 的 vBMD、微结构和刚度异常的程度和模式与 PMO 相似；与对照组相比，两组之间的差异相似。血清钙、肌酐、甲状旁腺激素、25-羟基维生素 D 和 24 小时尿钙没有差异。结论 虽然 DXA 表明脊柱和髋部的 aBMD 相对保留，但患有 1/3RO 的女性与患有典型 PMO 的女性相比，具有显着的微结构和生物力学缺陷。需要进一步的研究来指导该人群的治疗决策。