基于双能X线吸收测量法的三种胫骨软骨下骨骨密度测量方法的信度与效度分析

目的 观察基于双能X线吸收测量法(DXA)的三种胫骨近端软骨下骨骨密度检测方法的信度与效度。方法 招募28名健康女性,利用双能X线骨密度仪扫描膝关节;由2名研究者分别应用三种不同测量方法选取ROI进行测量分析,通过计算组内相关系数值(ICC),评价各方法的复测信度与测量者间信度,利用t检验评价区分效度。结果 三种方法均具有较好的复测信度(ICC 0.833~0.998)与测量者间信度(ICC 0.905~0.997),且对低年龄者和高年龄者具有较好的区分效度(P<0.05)。结论 利用双能X线骨密度仪研究膝关节软骨下骨具有可行性;本研究分析的三种测量方法可有选择地用于临床研究。     

Influence of orthopaedic metal and high-density detection on body composition as assessed by dual-energy X-ray absorptiometry

We examined the influence of orthopaedic material and computerized high-density detection (HDD) on analysis of bone mass and soft tissue composition performed by dual-energy X-ray absorptiometry (DXA). Measurements of total and regional bone area, bone mineral content (BMC), areal bone mineral density (BMD), lean tissue mass (LTM) and fat tissue mass (FTM) were made using a Norland XR-26 DXA scanner with dynamically changing samarium filtration. Twenty-one subjects who were free of metal implants were measured without and with a Biomet femoral prosthesis (titanium) placed on the proximal part of the femoral region. Twenty-one women with an endogenous prosthesis in the proximal femur were measured once. Analyses of tissue composition were performed without and with HDD using software provided by the manufacturer. Measurements were considerably affected by exogenous metal with overestimation of LTM and underestimation of FTM and bone area. BMC and BMD were over- or underestimated depending on the anatomical region. Enabling the HDD mode, values of bone area and tissue mass came closer to the expected values (–metal/–HDD) but were in general still significantly different from these. For the total body, the following significant changes were found after application of metal (+metal/–HDD vs. +metal/+HDD, mean values): bone area –19·8% vs. –6·9%, BMC +1·1% vs. –2·1%, BMD +26·5% vs. +4·7%, LTM +12·4% vs. +3·7%, FTM –15·8% vs. –7·0%. A similar pattern of change in tissue composition and bone area was found for the subregions of the body. Changes in tissue composition after HDD were similar in subjects with exogenous and endogenous metal, indicating that the experimental model was appropriate. In conclusion, measurements of tissue composition were substantially influenced by orthopaedic metal. HDD partly corrected for the artefacts induced by the metal.     

Bone mineral density measured by dual-energy X-ray absorptiometry in normal men

A cross-sectional study of 222 healthy Finnish men aged 20-69 years was performed to establish reference values of bone mineral density (BMD) using dual-energy X-ray absorptiometry (DEXA). The effects of age, and of some physical and lifestyle factors on BMD of the lumbar spine and proximal femur (femoral neck, Ward's triangle and trochanter) were investigated. The maximal mean BMD was observed at the age of 20-29 years in all the measurement sites. Except for the trochanteric area, BMD diminished along with age, the over-all decrements being 4%, 11%, and 23% in the lumbar, femoral neck and Ward's triangle areas, respectively. BMD was in a positive relationship to weight and height in all the measurement sites. The adjusted (for age, height and weight) BMDs were higher (P less than 0.05) in the group of daily dietary calcium intake greater than 1200 mg as compared with the group of lowest calcium intake (less than 800 mg day-1) in the three femoral areas. Cigarette smoking or alcohol drinking had no obvious effect on BMD.     

Correlation of quantitative heel ultrasonography with central dual-energy X-ray absorptiometric bone mineral density in postmenopausal women.

OBJECTIVES: In this study, we sought the proper cutoff level for quantitative ultrasonography (QUS) of the heel in identifying bone mineral density (BMD) categories as determined by dual-energy x-ray absorptiometry (DXA) in postmenopausal women. METHODS: With the use of DXA, BMD categories of the lumbar spine and different areas of the left femur of 420 healthy women according to World Health Organization definitions were determined. Quantitative ultrasonography of the heel was also performed in each subject. Receiver operating characteristic curves were plotted, and sensitivity and specificity of QUS to diagnose osteoporosis were examined at different points to identify the best cutoff level. The diagnostic agreement between the two techniques in identifying osteoporosis was assessed with kappa scores. RESULTS: The kappa scores were 0.31 for the lumbar region and 0.5 for the femoral neck region. On the receiver operating characteristic study, a score of -1 was found to be the appropriate cutoff point for QUS studies, in which the sensitivity of QUS to diagnose BMD osteoporosis varied between 78% and 87.5% depending on the site of the DXA study. With the proposed cutoff point (-1), sensitivity and specificity of QUS in detecting osteoporosis at the lumbar spine were 83.9% and 51%, respectively, and at the femoral neck were 84% and 50%, respectively. CONCLUSIONS: Insufficient agreement between QUS and DXA led to uncertainty on expected BMD in people tested by QUS. The proposed cutoff value could achieve higher sensitivity but only by accepting higher rates of false-positive results.     

Acute exercise affects dual-energy X-ray absorptiometry body composition estimates but not standardised ultrasound measurements of subcutaneous adipose tissue

Ultrasound has been demonstrated to be a highly accurate and reliable tool for measuring subcutaneous adipose tissue thickness and is robust against changes in hydration status or acute food or fluid intake. However, the effect of prior acute exercise is unexamined. This study examined the impact of an acute endurance exercise and resistance exercise session on standardised brightness-mode ultrasound measurements of subcutaneous adipose tissue thickness compared to skinfolds and dual-energy X-ray absorptiometry body composition estimates. In a randomised cross-over design, 30 active adults (24.2 ± 4.9 years) undertook physique assessment via standardised brightness-mode ultrasound, skinfolds and dual-energy X-ray absorptiometry before, immediately and 45 min after an acute endurance or resistance exercise session. The mean sum of eight subcutaneous adipose tissue thickness measured via standardised brightness-mode ultrasound increased (0.6 mm, p = 0.04) immediately postendurance exercise but was not meaningful when evaluated against the technical error of measurement of the investigator. A significant (p = 0.01) but not meaningful decrease in the sum of eight skinfolds occurred immediately (−1.1 ± 0.4 mm) and 45 min (−1.3 ± 0.4 mm) postresistance exercise. Comparatively, endurance exercise elicited a meaningful decrease of total mass (460 ± 30 g) and trunk lean mass (680 ± 90 g) dual-energy X-ray absorptiometry estimates. Findings from this study indicate standardised client presentation may be unnecessary when employing either standardised brightness-mode ultrasound or skinfolds for body composition assessment unlike dual-energy X-ray absorptiometry.     

前臂远端 1/3 和 1/10部位骨密度测量及临床意义

目的探讨前臂远端 1/3 和 1/10部位骨密度 ( BMD) 的变化规律 , 为骨质疏松症 ( OP) 的诊断治疗和预防提供科学依据 . 方法采用双能 X线骨密度仪 ( DEXA) 测定 1 863例健康人前臂远端 1/3 和 1/10部位的 BMD, 年龄范围 20～ 84岁 , 按 5岁一个年龄组进行统计分析 . 结果男、女 1/3部位骨峰值均在 40～ 44岁年龄组 , 男、女 1/10部位骨峰值分别为 30～ 34岁 , 25～ 29岁年龄组 . 前臂远端 1/3 和 1/10部位 BMD及 OP患病率也不同 ; 女性 45～ 54岁 1/10部位比 1/3部位显示更高的 OP患病率 ( P< 0.01). 结论女性围绝经期测量前臂远端 1/10部位 BMD可更早的发现 OP. 同时测定 1/3 和 1/10部位 BMD, 可较全面反映全身 ( 包括皮质骨和松质骨 ) 的骨量水平 , 有助于 OP的诊断和防治 .     

Within-subject variability in body composition using dual-energy X-rayabsorptiometry

The reproducibility of dual-energy X-ray absorptiometry (DXA)measure-ments for total body composition and for segmental body composition wasinvestigated in 22 healthy male subjects who underwent six consecutive measurements in 90min. Body weight (mean±SD) and body height were72·3±8·8 kg and 1·75±0·04 m respectively,and body mass index was 23·5±2·5 kg m^?2.Bone mineral content (BMC) was 3·30±0·36 kg, lean mass and fatmass as measured by DXA were 57·1±6·1 kg and11·8±6·5 kg respectively. For BMC, the reproducibility, expressed asthe coefficient of variation, was 1·2%, 1·5%,2·5%, 4·1% and 3·1% for total body, legs, arms,trunk and abdominal respectively. For lean tissue and for fat tissue, these values were1·5% and 5·0%; 1·8% and2·1%, 8·3% and 11·7%, 2·6%and 10·0%, 3·9% and 10·7% respectively. It isconcluded that the reproducibility for BMC is excellent, but that for lean tissue and for fattissue the variability is relatively high, especially in body segments.     

双能X线吸收与定量CT对比评价北京地区中老年女性与年龄相关的骨丢失

目的 采用双能X线吸收(DXA)和定量CT(QCT)对比评价北京地区中老年女性骨密度与年龄相关的骨丢失。方法 收集北京地区接受腰椎正位及髋部DXA检查(面积骨密度测量)的社区女性10 472名,接受腰椎QCT检查(体积骨密度测量)的女性562名。将接受两种检查的受检者分别按每10岁年龄段分组。计算各组别的平均骨密度,并计算峰值骨密度各组别的骨丢失率,分析骨密度与年龄间的相关性。结果 DXA测量北京地区女性腰椎、股骨颈及全髋部的峰值骨密度均在30~39岁年龄组,40岁以后各部位骨密度开始不同程度减低,至80~94岁组腰椎、股骨颈、全髋部累计骨丢失率分别为21.7%、31.4%和29.5%;QCT测量腰椎松质骨的峰值骨密度在20~29岁组,至80~97岁组累计骨丢失率达58.2%。累计骨丢失率从高到低依次为腰椎松质骨 >股骨颈 >全髋部 >腰椎正位。结论 腰椎QCT可较DXA更早、更准确地显示中老年女性的骨丢失情况,对增龄性骨丢失更敏感。     

脑卒中偏瘫患者骨密度变化及继发骨质疏松症的特点

目的：探讨脑卒中患者肢体瘫痪对其骨密度（BMD）和骨质疏松（OP）患病率的影响。方法：102例广东省佛山地区常住的脑卒中患者（脑卒中组），男46例，女56例，年龄55—85岁（平均72.8±9.2岁），使用美国 Hologic公司双能X线骨密度仪对正位腰椎（L1-L4）、双侧前臂远端和股骨近端进行BMD测定，并与352例本地区健康人（对照组）进行BMD及OP患病率的比较。结果：脑卒中组的偏瘫侧前臂、股骨颈、Ward′s区的BMD值明显低于健侧（0.444±0.11 vs 0.478±0.09，0.716±0.16 vs 0.757±0.16, 0.373±0.15 vs 0.407±0.15, P<0.05），偏瘫侧股骨颈、Ward′s区和腰椎BMD明显低于对照组（0.716±0.16 vs 0.844±0.12, 0.373±0.15 vs 0.495±0.13, 0.768±0.18 vs 0.831±0.13, P<0.05）。病程≥3个月的患者的偏瘫侧前臂、股骨颈和腰椎BMD明显低于病程<3个月的患者（0.415±0.10 vs 0.474±0.11，0.672±0.16 vs 0.751±0.16，0.722±0.14 vs 0.802±0.19，P<0.05），且病程≥3个月的患者的健侧BMD也低于病程<3个月的患者，但差异没有显著性（P>0.05）。女性脑卒中患者各部位的BMD明显低于男性（P<0.05）。脑卒中组偏瘫侧股骨的OP患病率高于健侧（P<0.05），男性腰椎和股骨、女性股骨的OP患病率高于对照组（P<0.05）。结论：脑卒中后偏瘫患者患侧前臂、股骨近端和腰椎BMD度低于健康人和健侧；女性患者BMD低于男性患者，病程越长，BMD越低。患侧肢体OP患病率高于健侧，脑卒中患者股骨的OP患病率高于健康人。     

双侧上肢训练在脑卒中患者康复中的应用

目的:初步观察双侧上肢训练对上肢功能中度到重度残损的恢复期脑卒中患者的疗效。方法:48例上肢功能中度到重度残损的恢复期脑卒中患者随机分为双侧训练组(n=24)、对照组(n=24),前者接受双侧(患侧、健侧)上肢同向、节律运动的重复练习,后者接受常规上肢训练,即以患侧上肢为主的单侧训练。两组患者上肢训练的时间均为1h/d,5d/周,持续4周,其余康复治疗如运动疗法和日常生活活动训练等两组均相同。两组患者分别于治疗前、治疗后予以FMA上肢部分(FMA-UE)、MAS上肢部分和MBI评定。结果:两组患者治疗后FMA-UE、FMA上肢的近端部分(FMA-PUE)和远端部分(FMA-DUE)、MAS-UE及MBI的评分均较治疗前提高,治疗前、后各量表的评分差异具有显著性(P<0.05);与对照组相比,双侧训练组患者FMA-UE、FMA-PUE的评分提高幅度更大(P<0.05)。结论:对于上肢功能中度到重度残损的恢复期脑卒中患者,采用双侧上肢训练可以更好地改善其患侧上肢,尤其是上肢近端的运动功能。     

Representativity of regional to total bone mineral in healthy subjects and 'anticonvulsive treated' epileptic patients. Measurements by single and dual photon absorptiometry

Dual photon (153Gd) and single photon (125I) absorptiometry were used to measure the regional bone mineral content (BMC) and density (BMD), as well as the total body mineral content (TBBM) and density (TBBD), in sixty-nine healthy subjects and in twenty-three epileptics on phenobarbitone. The BMCs (and BMDs) of all regions were significantly correlated to each other and to the TBBM (and TBBD). No difference in the ability to discriminate between the different study groups was found for the various regions, excepting the BMD of the head. The relationship between the forearm BMC and TBBM was highly significant, and identical in the five groups. The relationships between spinal BMC and forearm BMC, and TBBM differed in the five groups. It is concluded that some local measurement may be used as estimates of the total body bone mineral in some groups of patients with minor metabolic bone disease and healthy subjects.     

Assessment of the composition of major body regions by dual-energy X-ray absorptiometry (DEXA), with special reference to limb muscle mass

Summary Dual-energy X-ray absorptiometry (DEXA) has been used to assess and compare the composition of whole body and major body regions in 12 female (weight, 56.9 ± 6–2 kg; BMI, 17.25 kg m^-2) and 16 male (weight, 73.1 ± 9–6 kg; BMI, 20.28 kg m^-2) healthy subjects. Standard deviations (and % coefficients of variation) of the differences between repeated measurements of fat ranged from 0.11 kg (9.0%) for arms to 0.42 kg (30%) for whole body; for arm bone mineral, 0.01 kg (2.0%), and for fat-free soft tissue of the whole body, 0.42 kg (0.8%). Limb muscle mass was estimated using a new theoretical model of body composition, and the corresponding precision ranged from 015 kg (3.8%) to 0.27 kg (1.5%) for arms and total limb muscle mass, respectively. Proportions of each region consisting of fat were greater in females than in males (range, 20.31% vs. 16.18%), respectively, but the ratio of trunk to leg fat was lower (34:49% vs. 46:38%, respectively). Regional proportions of bone were similar between the sexes (all in the range 2.9–5.6%, for both females and males). Mean total limb muscle masses were 14.2 kg (arms, 2.8 kg; legs, 11.4 kg) for females and 22.2 kg (arms, 4.8 kg; legs, 17.4 kg) for males, which were 33.6% and 36.0% of fat-free mass, respectively. The correlation coefficients between limb muscle (DEXA) and other indices of muscle mass were: for DEXA vs. total body potassium, 0.90 (SEE 1.1kg muscle mass) to 0.94 (1.6 kg); and for DEXA vs. anthropometry, 0.43 (1.2 kg) to 0.85 (1.3 kg). Those for limb volume (DEXA) vs. anthropometric volume, 0.91 (0.78 1) to 0.94 (1.91 1). It is concluded that DEXA enables the valid and reproducible estimation of fat, fat-free soft tissue, bone, and limb muscle mass.     

虚拟现实技术在脑卒中患者偏瘫上肢功能康复中的应用

目的:初步观察虚拟厨房上肢康复训练结合常规作业治疗对脑卒中恢复期患者偏瘫上肢功能康复的临床疗效.方法:将33例脑卒中恢复期偏瘫上肢功能障碍的患者随机分为治疗组(16例)和对照组(17例).对照组接受常规作业治疗每次40min,每日1次,每周5次,共3周.治疗组接受常规作业治疗和虚拟厨房上肢康复训练各20min,每次共40min,每日1次,每周5次,共3周.其余康复治疗如运动疗法和日常生活活动训练等两组均相同.两组患者分别于治疗前、治疗后予以FMA上肢部分(FMA-UE)、MAS上肢部分(MAS-UE)和MBI评定,比较两组的疗效.结果:两组患者治疗后FMA-UE、MAS-UE及MBI的评分均较治疗前提高,治疗前、后各量表的评分差异具有显著性(P＜ 0.05);与对照组相比,治疗组患者FMA-UE、MBI的评分提高幅度更大(P＜0.05).结论:虚拟厨房上肢康复训练结合常规康复作业治疗能更好地改善脑卒中恢复期患者偏瘫上肢的运动功能,更有效地提高患者日常生活活动能力.     

虚拟现实训练对亚急性期脑卒中患者上肢运动功能的影响

目的:评估虚拟现实训练(采用Kinect体感交互技术)对亚急性期脑卒中患者上肢运动功能的影响及其神经电生理机制。方法:35例亚急性期脑卒中患者随机分为试验组和对照组。试验组接受虚拟现实上肢康复训练,对照组接受作业治疗。每次训练均为40min,每日1次,每周5次,共4周。在训练前后评估两组患者的上肢简化Fugl-Meyer运动功能评分(FMA-UE)、美国国立卫生院神经功能缺损评分(NIHSS)、改良Barthel指数,同时检测正中神经体感诱发电位(SEP)。对两组患者训练前后的FMA-UE、NIHSS、改良Barthel指数、正中神经SEP N20和P25的振幅、潜伏期进行训练前后组内及组间对比。结果:两组患者治疗后患侧正中神经SEP N20和P25的潜伏期均较治疗前缩短(P0.05),患侧FMA-UE和改良Barthel指数的评分均较治疗前提高(P0.05),且试验组较对照组FMA-UE提高幅度更大(P0.05)。两组患者治疗前后的NIHSS、患侧正中神经SEP N20和P25的振幅差异无显著性意义(P0.05)。结论:基于Kinect体感交互技术的虚拟现实训练在改善亚急性期脑卒中患者偏瘫上肢的运动功能方面较作业治疗有优势。亚急性期脑卒中患者正中神经SEP N20和P25的潜伏期在4周康复训练后缩短(P0.05)。     

支气管哮喘患者腰椎和股骨近端骨密度测量

目的 观察接受糖皮质激素（ＧＣ）治疗的支气管哮喘患者骨矿物质密度的变化。方法采用双能Ｘ线骨密度仪（ＤＥＸＡ）测量２６例接受ＧＣ治疗的支气管哮喘患者和年龄、性别匹配的２６例正常健康者的腰椎２～４（Ｌ_（２～４））和右侧近端股骨（股骨颈、大转子和Ｗａｒｄ’ｓ三角区）的骨密度（ＢＭＤ）。结果接受 ＧＣ治疗支气管哮喘患者 Ｌ_（２～４）、右侧股骨近端的 ＢＭＤ测量值（ｇ／Ｃｍ~２） 明显低于年龄和性别匹配的正常健康者,且与ＧＣ用药时间呈显著负相关。结论接受ＧＣ治疗支气管哮喘患者存在明显的骨质丢失,并与ＧＣ用药时间密切相关。     

强制性使用运动疗法在脑卒中和脑外伤上肢康复中的应用

目的：定量评价强制性使用运动疗法在脑卒中和脑外伤中的康复效果。方法：9例脑卒中和脑外伤患者使用夹板固定限制健侧手，患侧手进行每日6小时康复训练，共2周；在治疗前2周，治疗前和治疗后分别采用Carrol上肢功能评定和金子翼上肢功能评定对患者进行评价。结果：治疗后和治疗前及基线相比，两种评价方法值均具有显著性差异（P＜0．05）。结论：强制性使用运动疗法对脑卒中和脑外伤上肢功能有显著的康复效果。     

双能X线骨密度仪检查及数字化X线摄影术用于骨搬移术后

目的 观察骨搬移术后应用双能X线骨密度仪（DEXA）检查及数字化X线摄影术（DR）的价值。方法 对19例因胫骨外伤致感染性骨不连及大面积骨缺损接受胫骨搬移术患者分别于术后2、4、6及8周、停止搬移即刻、停止搬移后4、8周、去外固定架前4周及去外固定架即刻行DEXA和DR检查,观察不同时间点胫骨搬移区新生骨痂（BMD_新生骨痂）和截骨上下端原骨质骨密度（BMD_{截骨上下端}）及二者比率,分析DR图像中胫骨新生骨痂的形态及填充量。结果 胫骨搬移术术后各时间点BMD_新生骨痂、BMD_{截骨上下端}及BMD比率总体差异均有统计学意义（P均<0.05）。BMD_新生骨痂及BMD比率在术后2周分别为（0.07±0.01） g/cm²及（5.56±1.24）%,且均随术后时间延长而升高（P均<0.05）;BMD_{截骨上下端}在术后2周为（1.21±0.07） g/cm²,随时间延长而降低,去外固定架前4周降至最低（P均<0.05）、去外固定架即刻有所升高但与前者差异无统计学意义（P>0.05）。DR显示,术后4周胫骨搬移始区见新生骨痂影,随时间延长而呈多形态变化;术后2周胫骨搬移区未见新生骨痂填充,至停止搬移即刻新生骨痂填充量达25%,停止搬移4、8周达50%、75%,去外固定架前4周基本达100%。结论 DEXA能动态监测骨搬移术后搬移区新生骨痂及截骨端原骨质BMD;DR可显示新生骨痂形态变化;骨搬移术后联合应用二者有助于评估预后。     

脑卒中患者骨密度变化及其影响因素

目的:研究脑卒中患者骨密度(BMD)变化及影响因素。方法:采用双能X线BMD仪对32例脑卒中患者(卒中组)患侧股骨和10例健康人(对照组)股骨进行BMD及T分值检测,分析影响BMD变化的可能因素。结果:卒中组患者BMD明显低于对照组(P0.01);回归分析显示,卒中组患者患侧股骨颈(Neck)BMD与性别呈负相关,三角区(Ward)BMD与病程呈负相关(均P0.05);大转子(GT)BMD与性别呈正相关(P0.01),与病程呈负相关(均P0.01)。T分值分析中,GT有相关的影响因素为性别,即男性T分值高于女性。结论:脑卒中患者患侧股骨BMD明显下降;性别和病程与BMD改变密切相关,是主要影响因素。     

Comparison of the Achilles Express ultrasonometer with central dual-energy X-ray absorptiometry

BACKGROUND: Quantitative ultrasound (QUS) devices provide portable, easy-to-operate, low-cost options for point-of-care screening of bone mineral density (BMD). Community pharmacists should be aware of the precision, sensitivity, and specificity of these devices prior to their purchase. OBJECTIVE: To determine the precision, sensitivity, and specificity of the Achilles Express ultrasonometer compared with central dual-energy X-ray absorptiometry (cDXA) as well as its utility as a bone density screening device in the community pharmacy setting. METHODS: A prospective study in a community pharmacy and outpatient ambulatory clinic was conducted with 2 groups of white women. Group 1 participants were 25-35 years of age (young, healthy), and those in Group 2 were 45 years of age or older (postmenopausal). BMD assessments of the spine and the nondominant wrist and hip were performed using cDXA. Assessments of the heel were performed using the Achilles Express, a QUS device. The main outcome measures were correlation of t-scores between cDXA and QUS measurements using the Pearson correlation test. RESULTS: Twenty-two (30 +/- 4 years of age) and 31 (55 +/- 17 years of age) women were enrolled into Groups 1 and 2, respectively. Significant correlations between QUS and hip and spine cDXA t-scores were found in both groups. Correlation coefficients for QUS versus hip cDXA were 0.51 (95% CI 0.11 to 0.77) and 0.70 (95% CI 0.46 to 0.85) in Groups 1 and 2, respectively. Correlation coefficients for the QUS versus spine cDXA were 0.64 (95% CI 0.31 to 0.84) and 0.60 (95% CI 0.31 to 0.79) in Groups 1 and 2, respectively. The QUS device has a sensitivity level of 88% and specificity of 71% to detect a hip cDXA t-score of less than-1. CONCLUSIONS: The Achilles Express ultrasonometer is a reasonable screening tool to detect low BMD in postmenopausal women.