腰椎前后位骨密度检测结果的正确评价

A study on correct evaluation of the result of lumbar bone mineral density in anterioposterior position

目的根据骨密度（ＢＭＤ）＝骨矿含量（ＢＭＣ）／面积（Ａｒｅａ）的关系，旨在通过对ＢＭＣ及面积正常范围的评价，进一步判断ＢＭＤ的准确性。方法采用双能Ｘ线骨密度仪（ＤＥＸＡ）进行不同性别人群骨峰值年龄段及平衡峰值期ＢＭＤ的估价，计算其ＢＭＣ及面积均值，以身高为自变量，ＢＭＤ为因变量，分别作直线回归分析，建立ＢＭＣ、面积与身高的回归方程，利用其回归方程进行ＢＭＤ正常参考值的预测。结果平衡峰值ＢＭＤ的年龄，男性为２０～４９岁，女性为３０～４９岁；ＢＭＣ及面积的均值，男性分别为５６．４７ｇ及４６．３９ｃｍ２，女性分别为４７．４１ｇ及４１．１２ｃｍ２；９０％正常范围：男性ＢＭＣ（ｇ）＝０．３２７×身高（ｃｍ）±１４．７６，面积（ｃｍ２）＝０．２７１×身高（ｃｍ）±５．９６；女性ＢＭＣ（ｇ）＝０．２９４×身高（ｃｍ）±１１．８５，面积（ｃｍ２）＝０．２２５×身高（ｃｍ）±５．００。结论在临床工作中仅靠腰椎ＢＭＤ结果进行评价是远远不够的，应正确评价腰椎的ＢＭＣ及面积，方能对其ＢＭＤ的可靠程度作出判断。

Objective To assess the correctness of bone mineral density (BMD) from evaluation of the normal range of bone mineral content (BMC) and area. Methods On the basis of the epidemiological studies of lumbar BMD in 1 567 cases with dual energy X ray absorptiometry (DEXA), the age groups of BMD balancing peak value stage were evaluated in both sexes and the mean BMC and area values were calculated. Prediction of normal BMD value was done by regression equations established from BMC, area and height. Results The age group of BMD in balancing peak value was 20 49 years old in men and 30 49 years old in women. The BMC and area value, in men was 56 47g and 46 39cm 2,respectively, and 47 41g and 41 12cm 2 in women, respectively. Ninety percentage normal range, BMC(g)=0 327×height (cm) ±14 76, area(cm 2)=0 271×height (cm)±5 96 in men and BMC(g)=0 294×height (cm)±11 85,and area(cm 2)= 0 225×height(cm)±5 00 in women. Conclusions It is not enough only to evaluate the lumbar BMD in the clinic. The lumbar BMC and area should be evaluated correctly in order to get a reliable BMD assessment.