牵张成骨中骨密度测定方法的研究

目的:研究兔牵张成骨过程中骨密度的变化,并对骨密度新型测量方法评定。方法:日本大耳白兔24只,随机分为空白对照组、牵张术后1 d、1周、2周、4周、6周组,每组4只。随机选取一侧下颌骨行牵张成骨术。处死后的兔游离下颌骨根据阿基米德原理行骨密度测量、单能X线骨密度仪测量和钙含量测定,利用SPSS 19.0统计软件分析各组骨密度的差异并通过单能X线骨密度标准评定阿基米德原理测量骨密度值方法,分析骨密度与钙含量的相关性。结果:阿基米德原理骨密度测量、单能X线骨密度仪测量和钙含量测定均显示牵张区骨密度和钙含量逐渐增加,6周组与对照组无显著性差异,基本接近正常骨密度和钙含量,且变化趋势相同。阿基米德原理骨密度测量与单能X线骨密度仪测量正性相关,回归方程:Y_单能X线=-0.227+0.457X_阿基米德;骨密度与钙含量正性相关,回归方程:Y_钙含量=-623.579+483.473X_{阿基米德骨密度}。结论:阿基米德骨密度测量方法尽管在手段上不够先进,但其可以准确描述牵张成骨过程中骨密度的变化,可以简化实验流程,降低研究费用,有利于实验研究的广泛采用。同时合并钙含量的测量,基本可以准确描述骨发生过程中骨质结构变化的过程和程度。     

Forearm Single X-Ray Absorptiometry in the Identification of Postmenopausal Women With Osteoporosis at the Hip and Spine: A Correlation Study

The International Society for Clinical Densitometry (ISCD) has stated that forearm bone mineral density (BMD) testing combined with a thorough clinical evaluation may be an option for the diagnosis of osteoporosis when central bone density (CBD) testing is not available. This study assessed the performance of two different forearm sites in identifying subjects with spinal and femoral osteoporosis, and defined the 90% sensitivity point for the DTX-100 bone densitometer in the detection of central osteoporosis. Four hundred and two postmenopausal Bulgarian women between the ages of 50 and 81 yr (mean age 60.24 +/- 10.48 yr) participated in this study. Forearm BMD (distal and ultradistal forearm) was measured with a DTX-100 device (Osteometer Meditech, USA) and central BMD (lumbar spine and proximal femur) with a Hologic QDR 4500 A device. Linear T-score correlations among sites, sensitivity and specificity of the forearm site were analyzed. T-score correlations between the forearm and the central sites ranged from 0.32 to 0.69 (p < or = 0.05 for all correlations in age group 50-59). The forearm site sensitivity increased slightly with advancing age, but specificity decreased. When the distal forearm BMD cut point (0.340 g/cm2) was set to achieve 90% sensitivity to identify total hip osteoporosis, specificity was 40%; when the distal forearm BMD cut point (0.410 g/cm2) was set to achieve 90% sensitivity to identify spinal osteoporosis, specificity was 55.4%; when ultradistal forearm BMD cut points (0.280 and 0.320 g/cm2) were set to achieve 90% sensitivity to identify total hip and spinal osteoporosis, specificity was 40.8 and 59.2%, respectively. Forearm bone density measures may be useful to selectively screen for patients with central osteoporosis.     

Comparison of bone densitometry of the phalanges,distal forearm and axial skeleton in early postmenopausal women participating in the EPIC study

We present baseline bone densitometry from the Early Postmenopausal Interventional Cohort study (EPIC, sponsored by Merck, Sharp & Dohme) for the first time, in which 1609 women from England, Oregon, Hawaii and Denmark are participating to investigate the efficacy of daily oral alendronate to prevent early postmenopausal bone loss. We compared radiographic absorptiometry (RA) of the phalanges for bone mineral density (BMD) measurement with single-energy X-ray absorptiometry (SXA) of the distal forearm, and dual-energy X-ray absorptiometry (DXA) of the lumbar spine, proximal femur and distal forearm. In a random subgroup of 308 women, aged 45–60 years, on average 6 years since menopause (YSM), bone densitometry was measured once at baseline by RA of the phalanges besides the mandatory measurements by DXA. Bone densitometry was furthermore measured by SXA at the Danish site (89 women). Sixty-eight of the women had duplicate measurements performed within 1–3 weeks to evaluate the short-term precision error (CV%). One hundred and one healthy premenopausal women, aged 25–48 years, were recruited at the Danish and Hawaiian sites to establish a reference group. The precision error was 1.5% for RA of the phalanges and in the range 1.0–2.2% for SXA and DXA. BMD by RA correlated with BMD measured by SXA and DXA in the range 0.45<r<0.72 (p<0.001). In conclusion, bone densitometry by RA of the phalanges is highly correlated with bone densitometry by SXA and DXA. RA of the phalanges has a short-term precision error comparable to that of SXA and DXA.     

济南市1116例中老年人跟骨骨密度分析

目的探讨济南市中老年人骨质疏松的患病情况，为老年病工作者和老年人群的骨保健提供资料。方法对1116例中老年人健康查体者应用单能X线骨密度仪测量的右跟骨骨密度资料进行了回顾性分析，比较了骨密度与年龄和性别的关系。结果①在男性和女性45岁以上的人群中，随着年龄的增大，T值和BMD均逐渐降低，女性的降低幅度明显高于男性（P〈0．05）。②骨量减少和骨质疏松者在60岁以上男性中占60％，75岁以上占70％；骨质疏松患病率男性65岁～69岁组约占5％，70岁～74岁组约占10％，大于75岁组在20％以上。45岁～49岁的女性有30％的骨量减少；骨量减少和骨质疏松在女性50岁～54岁约占45％，55岁～59岁约占80％，60岁～69岁约占90％，70岁以上者高达99％。骨质疏松患病率在女性50岁～54岁近10％，55岁～59岁近30％，60岁～64岁近40％，65岁～69岁50％以上，70岁以上在70％以上。女性的骨质疏松患病率明显高于男性（P〈0．01）。③骨密度测定结果与年龄的相关性分析也显示，T值和BMD与年龄呈显著的负相关（P〈0．05），在女性其相关性更强。④以年龄为自变量，以T值和BMD为应变量，进行曲线拟合也看出，无论在男性还是在女性，T值和BMD随年龄的增大而逐渐变小，在女性曲线更陡。结论在中老年人群，随着年龄的增大，骨密度逐渐降低，骨质疏松的患病率明显增加，尤其在女性更为明显。     

Comparison of Quantitative Ultrasound Measurements in Calcaneus with DXA and SXA at Other Skeletal Sites: A Population-Based Study on 280 Children Aged 11–16 Years

We performed ultrasound measurements (QUS) of the calcaneus in a population-based setting on 280 healthy children, aged 11–16 years, from a small urban area in southern Sweden. The results are compared with dual-energy X-ray absorptiometry (DXA) measurements in the total body, the lumbar spine and the hip, as well as single-energy X-ray absorptiometry (SXA) of the forearm. Normative data and correlations between the three different techniques were determined. We found significant correlations between QUS and age (r= 0.34–0.54), height (r= 0.13–0.56) and weight (r= 0.30–0.60), and between QUS and bone mineral density (BMD) measurements (r= 0.44–0.70). Boys increased all their bone mineral variables with age, whereas girls showed a decreasing trend from age 15 years. QUS had a significantly higher increase in standardized value with age than Ward's triangle BMD, but a significantly lower increase in standardized value with age than distal radius (cortical site) BMD. At other BMD sites we did not find any significant differences compared with QUS regarding changes with age. The measurements obtained by QUS, DXA and SXA, respectively, were divided into quartiles. Of all subjects in the lowest quartile for QUS measurements, only 34–50% were also in the lowest quartiles for DXA and SXA measurements. In conclusion, QUS measurements of the calcaneus in children show similar results as for adult regarding the correlation with DXA and SXA; they also have a significant correlation with anthropometric data. QUS did not identify the same individuals with low bone mass as the X-ray techniques. Received: 23 June 1997 / Accepted: 21 January 1998     

2型糖尿病患者不同部位骨密度测定对结果的影响

目的探讨2型糖尿病患者不同部位的骨密度测定对结果的影响.方法分别采用定量CT(quantitative CT,QCT)和SXA(单能X线)测量了2型糖尿病患者腰椎松质骨的骨密度(bone mineral density,BMD)与脚跟骨的骨密度.结果各年龄组男女患者的骨密度与正常对照组相比均无显著性差异;糖尿病合并肾病组QCT测得的椎体骨密度明显低于无肾病组,而SXA测得的跟骨骨密度在女性低于无肾病组,男性则无差异.结论2型糖尿病肾病会导致骨量减少,但测量仪器、测量部位以及分组方法的不同会影响所得的结果.     

甲状腺机能亢进症患者治疗后骨密度的评估

目的：研究甲状腺机能亢进症（简称甲亢）患者经抗甲状腺药物治疗后骨密度的改善情况。方法：用单能X线骨吸收仪（SXA）测量48例绝经前妇女和50岁以前男性甲亢患者及19例健康人群的骨密度,同时测定甲亢患者的血清甲状腺功能,自甲亢诊断和治疗开始分为3组,即A组：≤3个月,B组：3～12个月,C组：〉12个月,对治疗后不同阶段的骨密度进行评估,并与健康人群进行比较。结果：B组骨密度（-1.41±0.25）较A组（-2.02±0.74）无明显改善（P〉0.05）,C组骨密度（-0.14±0.74）较A、B两组明显升高（均P〈0.01）,且与健康对照组（-0.12±0.68）比较差异无显著性（P〉0.05）。不同阶段TSH,FT3,FT4与骨密度没有相关性。结论：甲亢患者的骨量减少或者骨质疏松经抗甲状腺药物治疗后具有一定的可逆性。