广州地区双侧股骨近端双能X射线吸收法测量骨密度1055名的临床价值

Clinical value of dual-energy X-ray absorptiometry in the measurement of bilateral femoral bone mineral density in 1055 cases

目的:观察双侧股骨近端相应部位骨矿密度的差异性,探讨双能X射线吸收法测量双侧股骨近端的诊断价值。方法:选择2001-11/2005-12在暨南大学附属第一医院进行骨密度测量的广州地区受试者1055例(女性组789例、男性组266例)。①所有受试者进行了双侧股骨近端(股骨颈、股骨转子区、股骨颈上部和整体髋关节)双能X射线吸收法骨密度测量,比较双侧股骨近端骨密度。②从受试者中筛选出绝经后妇女500例,按照世界卫生组织1994年制定的方案,依据双侧股骨近端各测量部位的最低T值进行诊断,比较双侧股骨近端骨密度测量结果在诊断水平上可造成的差异。③从受试者中随机选取30例(男8例,女22例,年龄21～72岁,平均42.1岁)同时进行了两次骨密度测量,计算各测量部位的精密度和最小显著变化值。结果:①女性组和男性组双侧股骨近端各测量部位骨密度值呈高度正相关(r=0.88～0.97,P<0.001)。男性组各部位骨密度值双侧差异均不显著;女性组中整体髋关节的骨密度值存在较小的但有统计学意义的差异(骨密度差值=0.030g/cm2,t=2.387,P=0.017),右侧高于左侧。②在500例绝经后妇女中,左右侧股骨近端结果一致者83.2%(416/500),84例(16.8%)双侧测量结果可产生不一致的诊断。经精密度校正后7.0%(35/500)双侧测量结果可产生不一致的诊断。③股骨近端不同部位的单侧测量精密度在0.7%～2.2%,而相应部位的双侧测量精密度在0.6%～1.2%。双侧测量精密度比单侧测量提高20%～45%。结论:①广州地区女性股骨近端的骨密度值存在较小的但有统计学意义的差异。②双侧测量精密度比单侧测量提高,有助于监测骨矿物质密度变化。③有部分的个体双侧测量会改变单侧测量的诊断结果,单侧测量存在有漏诊的可能性。

AIM： To investigate the difference in bone mineral density （BMD） at the proximal end of bilateral femora, and explore the diagnostic value of dual-energy X-ray absorptiometry （DXA） densitometry in measuring the bilateral femoral BMD. METHODS： 1 055 subjects （including 789 females and 266 females） in Guangzhou district, who were measured of.the BMD between November 2001 and December 2005 in First Hospital Affiliated to Jinan University were selected. ①AII patients were measured of the BMD with DXA in dual femora （femoral neck, femoral trochanter, upper femoral neck and total hip joint）. The BMD in the proximal end were compared between bilateral femora. ② 500 postmenopausal females wore diagnosed based on the lowest T-score of bilateral measurement sites according to the diagnostic classification established by the World Health Organization. The differences in measurement of BMD in bilateral proximal ends Wore compared from the diagnostic level. ③ Thirty enrolled subjects （including 8 males and 22 females with the age ranged 21-72 years and the average age of 42.1 years） were measured of the BMD twice, and the changes precision as well as the least significant change （LSC） in each measurement site were calculated. RESULTS：①Thers was high positive correlation （r= 0.88-0.97, P〈 0.001 ） between the left and right femoral BMD values In both female group and male group, while there were no significant differences between bilateral femoral BMD values of each part in male group. There were small （mean BMD 0.030 g/cm^2） differences in BMD value of total hip in the female group, and there was statistical significance in the differences （BMD difference = 0.030 g/cm^2, t =2.387, P =0.017）, which was higher in the right femur than that in the left. ② In 500 postmenopause women, 83.2% （416/500） of them were with the same in the diagnosis between left and right femurs, and 84 patients （16.8%） Wore different in the diagnosis between left and right femurs. After precision correction, there was a diagnosis discordance in 7.0 % （35/500） of patients. ③The precision in unilateral measurement at different parts of femoral proximal ends ranged from 0.7% to 2.2%, while the precision in bilateral measurements at corresponding parts ranged from 0.6% to 1.2%. The precision in bilateral measurement was 20%-45% higher than the precision in unilateral measurement. CONCLUSION： ① There are significant but small differences between the right and left proximal femur BMD values in women of Gtiangzhou district.② The precision in dual femur measurements is higher than that in unilateral femur measurement, which contributes to detection of changes in BMD. ③ Partial dual measurement in individuals can change the diagnostic result of unilateral measurement, and there is possibility of missed diagnosis in unilateral measurement.