Musculoskeletal Quantitative Imaging Research Group, Department of Radiology and Biomedical Imaging, University of California, San Francisco, QB3 Building, Suite 203, San Francisco, California 94158, USA.
J Clin Endocrinol Metab. 2010 Nov;95(11):5045-55. doi: 10.1210/jc.2010-0226. Epub 2010 Aug 18.
Cross-sectional epidemiological studies have found that patients with type 2 diabetes mellitus (T2DM) have a higher incidence of certain fragility fractures despite normal or elevated bone mineral density (BMD).
In this study, high-resolution peripheral quantitative computed tomography was applied to characterize cortical and trabecular microarchitecture and biomechanics in the peripheral skeleton of female patients with T2DM.
A cross-sectional study was conducted in patients with T2DM recruited from a diabetic outpatient clinic.
Elderly female patients (age, 62.9 ± 7.7 yr) with a history of T2DM (n = 19) and age- and height-matched controls (n = 19) were recruited.
Subjects were imaged using high-resolution peripheral quantitative computed tomography at the distal radius and tibia. Quantitative measures of volumetric (BMD), cross-sectional geometry, trabecular and cortical microarchitecture were calculated. Additionally, compressive mechanical properties were determined by micro-finite element analysis.
Compared to the controls, the T2DM cohort had 10% higher trabecular volumetric BMD (P < 0.05) adjacent to the cortex and higher trabecular thickness in the tibia (13.8%; P < 0.05). Cortical porosity differences alone were consistent with impaired bone strength and were significant in the radius (>+50%; P < 0.05), whereas pore volume approached significance in the tibia (+118%; P = 0.1).
The results of this pilot investigation provide a potential explanation for the inability of standard BMD measures to explain the elevated fracture incidence in patients with T2DM. The findings suggest that T2DM may be associated with impaired resistance to bending loads due to inefficient redistribution of bone mass, characterized by loss of intracortical bone offset by an elevation in trabecular bone density.
横断面流行病学研究发现，2 型糖尿病（T2DM）患者尽管骨密度（BMD）正常或升高，但某些脆性骨折的发生率更高。
本研究应用高分辨率外周定量计算机断层扫描技术对 T2DM 女性患者外周骨骼的皮质和小梁微结构及生物力学进行了特征描述。
这是一项在糖尿病门诊招募 T2DM 患者的横断面研究。
招募了患有 T2DM 的老年女性患者（年龄 62.9 ± 7.7 岁，n = 19）和年龄及身高匹配的对照组（n = 19）。
使用高分辨率外周定量计算机断层扫描技术对桡骨远端和胫骨进行成像。计算了容积（BMD）、横截面积、小梁和皮质微结构的定量指标。此外，还通过微有限元分析确定了压缩力学性能。
与对照组相比，T2DM 组皮质旁的小梁容积 BMD 高 10%（P < 0.05），胫骨的小梁厚度高 13.8%（P < 0.05）。单独的皮质孔隙率差异与骨强度受损一致，在桡骨中具有统计学意义（>+50%；P < 0.05），而在胫骨中接近统计学意义（+118%；P = 0.1）。
这项初步研究的结果为标准 BMD 测量无法解释 T2DM 患者骨折发生率升高提供了潜在解释。这些发现表明，T2DM 可能与弯曲负荷抵抗力降低有关，其特征是皮质内骨丢失，被小梁骨密度升高所抵消。
