双能X射线骨密度仪测量离体羊股骨骨折端及钢板对接骨折端的骨密度

背景:目前,羊已逐渐成为骨质疏松研究中很有前途的动物模型。目的:采用双能X射线骨密度仪测量羊股部骨折断端及全部骨密度,探讨双能X射线骨密度仪测量过程中的准确度和精确度。方法:对双能X射线骨密度仪自带的Lunar腰椎模型扫描10次/d,确定机器准确度,再连续扫描25d,根据所测数据建立Shewhart控制图。选取3只羊中5根股骨进行7次重复扫描,采用骨密度仪自带的小动物分析软件分析羊股部骨折断端的骨密度、全部的骨密度,计算其精密度。另外选取4只羊8根股骨,用2种钢板对骨折断端固定,分析骨密度及骨矿含量的变化。结果与结论:双能X线骨密度仪的准确度为-1.0%,离体羊股部骨折断端及全部的骨密度测量精密度为0.005～0.537g/cm2。股骨全部骨和骨折断端密度的短期精密度分别为0.8%和1.5%,股骨全部和骨折断端骨矿物含量的短期精密度为0.9%和7.5%。不同钢板固定后的羊股骨骨密度、骨矿含量差异无显著性意义。结果证实,双能X射线骨密度仪能准确测量离体羊股骨的骨密度,但在骨折断端骨矿含量精密度分析有一定的误差。     

双能X射线骨密度仪测量离体羊股骨骨折端及钢板对接骨折端的骨密度

背景：目前,羊已逐渐成为骨质疏松研究中很有前途的动物模型。目的：采用双能X射线骨密度仪测量羊股部骨折断端及全部骨密度,探讨双能X射线骨密度仪测量过程中的准确度和精确度。方法：对双能X射线骨密度仪自带的Lunar腰椎模型扫描10次/d,确定机器准确度,再连续扫描25d,根据所测数据建立Shewhart控制图。选取3只羊中5根股骨进行7次重复扫描,采用骨密度仪自带的小动物分析软件分析羊股部骨折断端的骨密度、全部的骨密度,计算其精密度。另外选取4只羊8根股骨,用2种钢板对骨折断端固定,分析骨密度及骨矿含量的变化。结果与结论：双能X线骨密度仪的准确度为-1.0%,离体羊股部骨折断端及全部的骨密度测量精密度为0.005～0.537g/cm2。股骨全部骨和骨折断端密度的短期精密度分别为0.8%和1.5%,股骨全部和骨折断端骨矿物含量的短期精密度为0.9%和7.5%。不同钢板固定后的羊股骨骨密度、骨矿含量差异无显著性意义。结果证实,双能X射线骨密度仪能准确测量离体羊股骨的骨密度,但在骨折断端骨矿含量精密度分析有一定的误差。     

腰椎和髋部骨密度测定在骨质疏松诊断上的相关性分析

目的:通过分析腰椎和髋部骨密度,评价两者在骨质疏松诊断上的差别和意义。方法:2000-01/2004-03在中国长城铝业公司总医院经双能X射线骨密度仪检查确诊为骨质疏松的190例患者,按年龄进行分组,分析不同年龄、不同部位骨量减少和骨质疏松的发生率。结果:腰椎和髋部的骨质疏松发生率与年龄存在正相关关系(χ2=20.7328,32.1887,P<0.05,Pearson列联系数0.3137,0.2336,Cramer列联小数0.2336,0.2910),符合人体骨质疏松发生发展变化规律。腰椎和髋部的骨质疏松和骨量减少发生率在各年龄组之间差异均无显著性意义(χ2=7.2082,3.1846,P>0.05)。结论:腰椎和髋部的双能X射线骨密度仪测量部位选择应综合分析与判断,以期达到早期发现与治疗骨质疏松,预防骨折的发生。     

双能X线骨密度仪椎体骨密度测定骨质疏松症临床价值分析

目的:对骨质疏松症应用双能X线骨密度仪测定锥体骨密度的临床疗效展开分析。方法:选择我院2018年11月-2019年期间收治的80例骨质疏松患者作为研究对象,对所有患者均实施双能X线骨密度仪,测定不同年龄阶段椎体骨质疏松的情况。结果:不同年龄阶段骨质量测定的均值存在差异。根据骨密度的测定将其分为两个标准,骨密度≤x-2.0SD,骨密度≤x-2.5SD。经测定发现,所有患者的骨密度均不足x-2.0SD,其中65例骨密度不足。随着年龄的增长,骨质量均差的值越小。结论:对骨质疏松症应用双能X线骨密度仪测定锥体骨密度能够起到较高的临床应用价值,为临床治疗提供详细的数据,诊断价值较高。     

不同性别Singh指数与双能X射线骨密度仪测量骨密度的相关性

背景:Singh指数和骨密度测量是临床常用来了解骨强度及骨质疏松情况的方法,而二者之间的相关性及其性别差异性未见报道.目的:了解Singh指数与双能X射线骨密度仪测量骨密度在不同性别的相关性.方法:取股骨颈骨折行假体置换患者股骨颈标本42份,将42份标本按性别分组采用双能X射线骨密度仪测量体外股骨颈骨密度值;对术前X射线片进行Singh指数分级,了解Singh指数与骨密度的双变骨量相关性.结果与结论:男性Singh指数与骨密度的双变骨量相关性分析结果显示,Spearman相关指数r=0.646,P=0.002,二者有非常显著的相关性,并且男性骨密度值与Singh指数有正相关性,根据二者的检查结果可初步判断患者骨质疏松情况;女性Singh指数与骨密度的双变骨量相关性分析结果显示,Spearman相关指数r=0.304,P<0.181,二者无统计学上的相关性,说明女性患者因绝经后骨质疏松加剧,骨密度值与Singh指数相关性不明确,临床治疗时需根据个体情况采用不同治疗方法.     

双能X射线骨密度仪测量不同条件下腰椎骨矿含量、椎骨骨面积有临床意义的最小变化率

目的:骨密度仪的差异或漂移可以通过质控加以校正。比较双能X射线骨密度仪测量腰椎铝体模、活体腰椎、死体腰椎(带软组织)的骨矿含量、椎骨骨面积有临床意义的最小变化率差异,以便为重复测量同一个体的骨矿含量或骨密度评估临床药物疗效提供依据。方法:实验于2004-05/2006-12在川北医学院人体解剖实验室与川北医学院附属医院内分泌科骨密度室完成。采用美国Lunar公司生产的DPX-MD双能X射线骨密度仪测量铝体模、3个活体椎体、1个带软组织的死体椎体的骨矿含量与椎骨骨面积,3次/d,连续测定5d。3个活体椎体分别为38岁骨密度正常男性、40岁骨质疏松症男性及62岁轻微骨量减少女性的椎体,均为自愿参与实验的本院医生。死体椎体由川北医学院人体解剖实验室提供。实验得到医院伦理道德委员会批准。计算各椎体骨矿含量、椎骨骨面积的变异系数及有临床意义的最小骨矿含量、椎骨骨面积变化率。结果:①有临床意义的最小骨矿含量变化率:铝体模与正常男性椎体最小,骨质疏松症男性椎体、轻微骨量减少女性椎体与死体椎体呈依次增大趋势,且以死体椎体最大。②有临床意义的最小椎骨骨面积变化率:铝体模、正常男性椎体与骨质疏松症男性椎体最小,轻微骨量减少女性椎体与死体椎体较大,且以死体椎体最大。结论:双能X射线骨密度仪测量不同条件椎骨有临床意义的最小骨矿含量、椎骨骨面积变化率存在差异,骨质疏松的严重程度不同,骨矿含量、椎骨面积骨密度检测对临床药物疗效观察的影响不同,骨质疏松越严重或有骨质增生的存在对其影响越大。     

双能X线骨密度仪在15 cm水深中测量骨密度的准确性

目的探讨双能X线骨密度仪(dual energy X-ray absorptiometry,DXA)测量骨密度的准确性.方法用DXA(前后位扫描)测量5具浸泡在15 cm水深中的猪腰段脊柱,共计20例椎骨,计算测量的结果与灰重及灰重密度相关性.结果骨矿含量与灰重呈显著正相关性(r=0.95,P＜0.01),而骨密度与灰重无明显相关性(r=0.41,P＞0.05).结论DXA测量骨密度中骨矿含量较准确,而骨密度较差.     

两种双能X射线吸收法骨密度仪数据共享:Challenger与Holigic仪器的交叉校正

背景：为达到数据共享的目的,不同厂家生产的双能X射线吸收骨密度仪需要进行仪器之间的校正。目的：利用峰值骨量的人群尝试确立Challenger与Holigic QDR4500型DXA之间的数据换算关系。设计、时间及地点：数据直线相关及回归分析实验,于2007-10在青岛海慈医院骨密度室完成。对象：25～35岁符合青岛地区峰值骨密度的健康成年女性30人。方法：受试者分别经法国DMS公司产的Challenger型扇形束X射线吸收骨密度仪和美国Hologic公司产的QDR-4500A型扇形束X射线吸收骨密度仪测得骨密度值。主要观察指标：通过直线相关与回归分析分别计算出L2～4正位和左侧股骨颈、大转子、Ward三角区6个骨骼区域的骨密度换算公式,并进行青岛与长沙两地区健康女性多骨骼部位骨密度数据库校正前后的比较以验证公式的可行性。结果：两种骨密度仪测定得到的数据显著相关,存在线性关系。校正之前,青岛地区女性髋骨骨密度高于长沙地区;校正之后两地区骨密度无显著性差别。结论：峰值骨量人群可用于Challenger与Holigic QDR4500型双能X射线吸收骨密度仪之间的校正。     

超声骨密度测量仪临床应用价值研究

目的:探讨超声法诊断骨质疏松的临床应用价值。方法:采用随机、对照的临床试验方法,以随机编码的方式,对同一受试者先后利用试验仪器与对照仪器进行检查,对检测结果进行相关性和一致性分析。结果:1.超声骨密度仪与双能X射线骨密度仪所测参数T呈高度相关关系(r=0.84,P<0.01),线性回归方程为:T双能=1.1548T超声+0.7364;2.Bland-Altman一致性分析,两种方法测量参数T的超限率均为0,两仪器测量结果具有较高的一致性。结论:超声骨密度测量仪具有经济、安全、准确等优势,是一种值得推广应用的骨密度检测方法。     

老年性骨质疏松症发生发展的多因素分析

目的:初步探讨影响老年人骨密度(bonemineraldensity,BMD)变化的因素。方法:采用面对面问卷调查法,并采用美国Norland公司生产的XR-36型双能X射线骨密度仪测量60名老年人L2-4侧位骨密度和股骨颈、大粗隆、Wards区的骨密度。结果:除Wards区骨密度(P>0.05)外,其余各部分骨密度男女性别之间差异有高度的显著性意义(P<0.01,P<0.001),受试者年龄与骨密度呈负相关,体质量与骨密度呈正相关;饮食因素对骨密度有一定的影响,但差异无显著性意义。结论:老年人的骨密度受多种因素的综合影响。     

Body composition in Italian and Danish women

The objective of this cross‐sectional study was to compare the body composition and fat distribution measured by dual energy X‐ray absorptiometry (DPX, Lunar) in different age decades of age‐matched Danish and Italian women. The subjects comprised 133 healthy Italian women (age 20–60 years) age‐matched to a representative sub‐sample of healthy Danish women (n=375). Total and abdominal body fat tissue mass were measured by dual‐energy X‐ray absorptiometry. Italian women were shorter and fatter compared with age‐matched Danish women, but in middle‐age, had a less abdominal fat distribution. There was no difference in total body bone mineral density.     

Evaluation of a gel-coupled quantitative ultrasound device for bone status assessment.

OBJECTIVE: To evaluate a new gel-coupled calcaneal quantitative ultrasound system, Osteospace (Medilink, Montpellier, France), which was designed to assess the status of bone in the calcaneus. METHODS: The study group consisted of 215 healthy white women aged 20 to 85 years and 51 white women aged 60 to 86 years with osteoporotic fractures. Fifty-two healthy women aged 50 to 85 years were randomly selected from the healthy cohort as the control group. All the women had calcaneal quantitative ultrasonic measurements. The women with osteoporotic fractures and the control group also had proximal femur and lumbar anteroposterior spine bone mineral density measurements using dual X-ray absorptiometry. Bone mineral density was also measured in a subgroup of 54 women at the calcaneus. RESULTS: There was a significant inverse correlation of broadband ultrasound attenuation and speed of sound with age (P < .001). Short-term measurement precision values expressed as coefficients of variation were 1.72% for broadband ultrasound attenuation and 0.64% for speed of sound, and standardized short-term precision values were 6.09% for broadband ultrasound attenuation and 3.87% for speed of sound. The correlations between the quantitative ultrasonic parameters and calcaneal bone mineral density were 0.69 (P = .0001) for broadband ultrasound attenuation and 0.45 (P = .0008) for speed of sound. Both quantitative ultrasonic parameters and all bone mineral density measurements of the hip and spine differed significantly between the control and osteoporotic fracture groups (P < .01). Age-, weight-, and height-adjusted odds ratios per SD decrease were as follows: broadband ultrasound attenuation, 1.79; speed of sound, 1.83; spine bone mineral density, 2.34; femoral neck bone mineral density, 1.69; and total hip bone mineral density, 1.85. The areas under the receiver operating characteristic curve for quantitative ultrasound parameters and bone mineral density measurements were close, ranging from 0.75 to 0.80. CONCLUSIONS: This new quantitative ultrasound system can detect age- and menopause-related influences on skeletal status and can discriminate healthy women from those with osteoporotic fractures in a manner comparable with that of bone mineral density measurement by dual X-ray absorptiometry.     

运动对Ⅰ型原发性骨质疏松症形成的干预

目的观察运动对去卵巢雌性大鼠骨密度的影响。方法雌性SD大鼠随机分为空白组、去卵巢组、雌激素组及运动组。用双能X线骨密度测量仪,测量大鼠的全身及腰椎部骨密度,并称量大鼠体重和子宫重量。结果运动能抑制骨质疏松大鼠骨量的丢失和体重的增长(P<0.05),运动组大鼠的子宫系数明显低于雌激素组(P<0.01),与去卵巢组近似。结论运动对绝经后骨质疏松症的形成有一定干预作用。     

Lack of relationship between hip and spine bone mineral density and oral contraceptive use

Abstract. The aim of this study was to examine the relationships between oral contraceptive use and bone mineral density at the hip and spine.
Community based women aged 41–76 years ( n = 841) were recruited from four general practices in Cambridge. Each subject completed a health questionnaire. Spine (L2-L4, n = 841) and hip ( n = 833) bone mineral density were measured by dual energy X-ray absorptiometry using the Hologic QDR-1000.
After adjustment for age, there was no significant difference in regional bone mineral density between ever and never users of oral contraceptives. Similar results were obtained after stratifying for potential confounding factors including menopausal status, parity, smoking, hormone replacement therapy use, and body mass index. There was no relationship between duration of oral contraceptive use and bone mineral density.
These results suggest that there is no relationship between oral contraceptive use and bone mineral density at the hip and spine in middle-aged women.     

Comparison of dual-energy x-ray absorptiometry and dual photon absorptiometry for bone mineral measurements of the lumbar spine

A new x-ray-based (dual-energy x-ray absorptiometry [DEXA]) instrument for measurement of bone mineral in the spine and hips (QDR-1000, Hologic, Inc.) was compared with a commercial dual photon absorptiometry (DPA) instrument that uses a 153Gd source (DP3, Lunar Radiation Corporation). Measurements were made on phantoms and lumbar spines of patients to study accuracy, precision, limitations, and compatibility of results between instruments. Both instruments measure bone mineral of integral bone in terms of area bone density with an entrance exposure of less than 5 mR. For spinal bone mineral measurements, the DEXA instrument had a shorter scanning time and higher resolution images than the DPA system. The DEXA instrument also showed better precision in a spine phantom and reduced influence of thickness for patient measurement. For bone mineral content, accuracy was about equal for both instruments; for measurements of the area of the region of interest, accuracy was better with the DEXA instrument. With both instruments, fat had little effect on bone mineral density in bone phantom studies. Measurements on both instruments were influenced by the location of a bone phantom within the photon beam. Results in patients showed good correlation (r = 0.988) for bone mineral density. Measurements of bone mineral density in patients were consistently lower with the DEXA instrument because of better accuracy in area measurements. The new x-ray-based instrument is a major advance in bone mineral absorptiometry and provides improved, yet less expensive, measurements in research and clinical applications.     

Effects of silicone breast prostheses on the assessment of body composition by dual‐energy X‐ray absorptiometry

We examined the influence of silicone breast prostheses on body composition as assessed by dual‐energy X‐ray absorptiometry (DXA). Eighteen women were measured with and without a pair of silicone breast prostheses placed on the upper part of the trunk simulating endogenous implants. Bone area, bone mineral content (BMC), areal bone mineral density (BMD), lean tissue mass (LTM) and fat tissue mass (FTM) of the total body and of the subregions of the body, i.e. the head, trunk, arms and legs, were measured by a Norland XR‐36 DXA scanner. After application of the silicone prostheses, bone area, BMC and BMD of the total body significantly increased by an average of 3·7, 6·6 and 3·4% (P<0·0001), respectively. Total body LTM and FTM were not affected. In the trunk region, changes were more pronounced. Trunk BMC, for example, was overestimated by 17·9% (P<0·0001). The prostheses also influenced measurements of truncal soft tissue composition, with a small but statistically significant overestimation of both LTM (1·1%) and FTM (2·1%) (P<0·05). No changes in bone mass and soft tissue composition were seen in the head, arms and legs. Activation of a high‐density detection software utility provided by the manufacturer had no influence on any of the measurements. We conclude that silicone breast prostheses affect the assessment of body composition by DXA.     

Height change and bone mineral density: revisited

PURPOSE: To evaluate the relationship between height change, osteoporosis risk factors, and bone mineral density. SAMPLE: Secondary data collected on 168 healthy women, ages 50 to 65 years, who had a dual energy x-ray absorptiometry screening of the hip and spine to determine bone mineral density. METHOD: A quantitative secondary analysis of data that replicated in part a study by Hunt (1996). FINDINGS: The relationships between height change, osteoporosis risk factors, and bone mineral density were not significant for this group of healthy postmenopausal women. However, these women did not meet daily minimum requirements for dietary calcium intake and daily exercise. IMPLICATIONS: The good news is that healthy women ages 50 to 65 years still have time to engage in osteoporosis preventing behaviors to prevent bone loss and eventual height loss. The use of measured height change, as an indicator for osteoporosis risk, is a cost-saving tool and should be considered as one component of a comprehensive osteoporosis health appraisal incorporating daily calcium intake and exercise. Further research, with more precise measurement of height, needs to be done to evaluate the relationship between height change, osteoporosis risk factors, and bone mineral density.     

Age-related bone loss: relationship between age and regional bone mineral density

We assessed the changes in regional bone mineral density according to age and examined the relationship between various regional bone mineral densities. The study was conducted in 985 Japanese women divided into < 50-years group (n = 435) and > or = 50 years group (n = 550). The total body bone mineral density and that of the head, arm, leg, thoracic (T)-spine, lumbar (L)-spine, ribs, and pelvis were measured using dual energy x-ray absorptiometry. There was a significant generalized reduction of bone mineral density in all regions after the age of 50 years. The most marked age-related decrease was observed in the L-spine. Bone mineral densities in all regions significantly correlated to each other in both age groups, but the degree of significance varied among regions. The relationship between bone mineral density of the L-spine and that of T-spine regions was the most significant in both groups. In the < 50-years group, the correlation between bone mineral density of the pelvis and that of L-spine and T-spine was the highest, followed by that between the pelvis and the leg. On the other hand, in the > or = 50-years group, the correlation between bone mineral density of the pelvis and that of the leg was the highest, but not the L-spine or T-spine. Since spine measurements are affected by vertebral deformity and/or aortic calcification, our findings suggest the pelvis may be a useful region for screening measurements of bone mineral density, especially in older women.     

Proton pump inhibitor omeprazole use is associated with low bone mineral density in maintenance haemodialysis patients

Objective: Limited studies have shown that proton pump inhibitor (PPI) therapy may decrease bone density or insoluble calcium reabsorption through induction of hypochlorhydria. However, PPI therapy may also reduce bone resorption via inhibition of osteoclastic vacuolar proton pumps. The aim of this study was to determine whether the opposing effects of PPI therapy may cause clinically important alterations in bone mineral densitometry (BMD) parameters in maintenance haemodialysis patients. Methods: Sixty‐eight maintenance haemodialysis patients were enrolled in this study. Patients were classified into two groups involving users of PPI therapy (omeprazole 20 mg/day, group 1, n = 36 patients) and non‐users of acid suppression drugs (group 2, n = 32 patients). Patients had radius, hip and spine BMD assessed by dual‐energy X‐ray absorptiometry. Results: The mean duration of PPI therapy with omeprazole was 27 ± 5 months. The users of PPI therapy had lower values of bone mineral density and T‐scores at the anatomical regions than non‐users of acid suppression drugs. Serum calcium and phosphate levels, calcium‐phosphate product and serum intact parathormone levels and the ratio of users of vitamin D therapy were similar among groups. A mutivariable adjusted odds ratio for lower bone density associated with more than 18 months of omeprazole, when all the potential confounders were considered, was 1.31 in the proximal radius, 0.982 in the femur neck, 0.939 in the trochanter and 1.192 in the lumbal spine. Conclusion: The present data suggest that PPI therapy should be cautiously prescribed in maintenance haemodialysis patients, especially with lower BMD values.     

Quantitative ultrasound predicts bone mineral density and failure load in human lumbar vertebrae

BACKGROUND: Quantitative ultrasound is in widespread clinical use for assessment of bone quality at peripheral skeletal sites, but has not yet been applied to those sites in the axial skeleton, such as the spine and hip, where osteoporotic fractures are common. METHODS: Ultrasound measurements were made in 11 cadaveric vertebrae and relationships with bone mineral density and failure load were investigated. An ultrasonic imaging system was used to measure speed of sound, broadband ultrasonic attenuation, and attenuation at a single frequency, through the vertebral body in the sagittal plane. Ultrasonic measurements were averaged over a region of interest centrally within the vertebral body, and were calculated with and without normalization for bone size. Vertebral bone mineral density was measured in antero-posterior and lateral projections using dual energy X-ray absorptiometry. Compressive mechanical testing was performed to determine vertebral failure load. FINDINGS: Bone mineral density correlated with failure load (r=0.74-0.78, all P<0.01), and with quantitative ultrasound (r=0.63-0.82, P=0.038-0.004), in line with previous studies. Of the ultrasonic measurements, those parameters not normalized for bone size gave the highest correlations with failure load, ranging from r=0.71 (P=0.021) for speed of sound to r=0.93 (P<0.001) for attenuation. When ultrasonic measurements were normalized for bone size, the correlations with both failure load and bone mineral density were lower. INTERPRETATION: These results confirm the feasibility of vertebral quantitative ultrasound in vitro, and indicate that ultrasound does provide information on both bone mineral density and failure load. The predictive performance of ultrasonic measurements for failure load was comparable to or greater than that of bone mineral density, suggesting that ultrasound has the potential to be at least as useful as mineral density in the assessment of vertebral bone. Normalizing ultrasonic measurements for bone size reduced the strength of correlations because both bone mineral density and bone strength reflect bone size to a certain extent.