Pearson J, Dequeker J, Reeve J, Felsenberg D, Henley M, Bright J, Lunt M, Adams J, Diaz Curiel M, Galan F
MRC Clinical Research Centre and Northwick Park Hospital, Harrow, United Kingdom.
J Bone Miner Res. 1995 Feb;10(2):315-24. doi: 10.1002/jbmr.5650100220.
Measurements of the proximal femur by dual X-ray absorptiometry (DXA) are assuming increasing importance in clinical and epidemiological studies. However, different DXA manufacturers have adopted varying approaches to measuring the femoral neck and trochanter regions with the result that there is as yet no agreement on normal ranges and how to cross-calibrate between different machines. In this Concerted Action (of the EU's 2nd Framework Programme), 12 clinical centers in eight countries recruited a total of 855 female and 517 male Caucasian subjects who were judged to be free of conditions known to cause secondary osteoporosis and who had not been treated with drugs known to affect bone mass. The DXA machines used were made by Hologic, Lunar, and Norland. Each machine was cross-calibrated with the European Spine Phantom prototype designed by Kalender. All femoral neck and trochanter results were expressed as standardized values and were first examined for possible bias due to between-brand differences in choice of areas for measurement. On average, trochanter areas were similar between brands but Norland chose a narrower neck region for analysis. Bone mineral density (BMA or BMD g/cm2) was log-normally distributed for all groups at the femoral neck but normally distributed at the trochanter in men and postmenopausal women. There were substantial between-center differences after cross-calibration in age-adjusted mean values at both sites and also in the rates of apparent bone loss with age and the amounts of scatter within populations about mean age-adjusted values. With the proviso that locally derived normal ranges would allow more accurate comparisons for clinical purposes, European normal ranges were derived for both neck and trochanter. Data obtained with the three individual brands of machine fitted these overall ranges well. Bone loss was apparent in premenopausal women at the femoral neck but not the trochanter. Postmenopausal women's data was somewhat better fitted by reference to years since menopause than to chronological age. This work provides a basis for conducting future epidemiological and clinical studies with more than one brand of machine as long as each individual subject, if measured consecutively, is measured on the same machine throughout.
通过双能X线吸收法（DXA）测量股骨近端在临床和流行病学研究中变得越来越重要。然而，不同的DXA制造商采用了不同的方法来测量股骨颈和转子区域，结果是在正常范围以及如何在不同机器之间进行交叉校准方面尚未达成一致。在这个（欧盟第二个框架计划的）联合行动中，八个国家的12个临床中心共招募了855名女性和517名男性白种人受试者，这些受试者被判定没有已知会导致继发性骨质疏松的疾病，并且没有接受过已知会影响骨量的药物治疗。所使用的DXA机器由Hologic、Lunar和Norland制造。每台机器都与由Kalender设计的欧洲脊柱体模原型进行了交叉校准。所有股骨颈和转子的结果都表示为标准化值，并且首先检查了由于不同品牌在测量区域选择上的差异可能导致的偏差。平均而言，不同品牌之间的转子区域相似，但Norland选择了较窄的颈部区域进行分析。所有组在股骨颈处的骨矿物质密度（BMA或BMD，g/cm²）呈对数正态分布，但在男性和绝经后女性的转子处呈正态分布。交叉校准后，两个部位的年龄调整后平均值在中心之间存在显著差异，并且随着年龄的增长明显骨丢失率以及人群中围绕年龄调整后平均值的离散程度也存在显著差异。前提是本地得出的正常范围将允许进行更准确的临床比较，因此得出了股骨颈和转子的欧洲正常范围。用这三个不同品牌机器获得的数据很好地符合了这些总体范围。绝经前女性在股骨颈处有明显的骨丢失，但在转子处没有。绝经后女性的数据参照绝经后的年限比参照实际年龄拟合得稍好一些。这项工作为使用多个品牌的机器进行未来的流行病学和临床研究提供了基础，只要每个个体受试者如果连续测量，在整个测量过程中都在同一台机器上进行测量。
