Measurement of bone mineral density of lumbar spine and whole body in low-birth-weight infants: comparison of two methods

In the present study, we compared lumbar spinal and whole-body bone mineral density (BMD) measurements to determine which is more suitable for evaluating the bone mineral status of low-birth-weight (LBW) infants. Lumbar spinal and whole-body BMD were assessed simultaneously in a prospective series including 152 Japanese LBW infants (birth weight 453–2400 g, gestational age 24–38 weeks) from the age of 40 weeks post-conception to 2 years of age. Lumbar spinal BMD at 40 weeks post-conception was significantly correlated with birth weight (r = 0.74; P < 0.0001), but whole-body BMD was not correlated with birth weight. No correlation was found between lumbar spinal and whole-body BMD at 40 weeks post-conception. However, after 40 weeks post-conception, a significant correlation was found between lumbar spinal and whole-body BMD (r = 0.65; P < 0.0001). For infants with a body weight of 4 kg or less at the time of measurement, no correlation was found between lumbar spinal and whole-body BMD. However, for infants with a body weight above 4 kg, a significant correlation was found between lumbar spinal and whole-body BMD (r = 0.65; P < 0.0001). Thus, lumbar spinal BMD is more suitable than whole-body BMD for evaluation of the bone mineral status of LBW in early infancy. Therefore, lumbar spinal BMD should be used for serial evaluation of changes in the bone mineral status of LBW infants. Received: April 6, 2000 / Accepted: June 16, 2000     

Sustained bone mineral density changes after burn injury

BACKGROUND: Body-composition changes have been observed after burn injury. In particular, several studies have shown that bone mineral density (BMD) in burn patients is decreased when compared to the normal population. Little is known about the frequency, severity, or duration of these changes. The purpose of this study was to describe body-composition changes over time after burn injury. MATERIALS AND METHODS: Twenty-nine burn patients participated in this study. Portable dual-energy X-ray absorptiometry (pDEXA) measuring forearm BMD, fat, and lean mass was obtained as soon as possible after admission and repeated bi-weekly until discharge and, when possible, for 2 years post-injury. The scan showing the greatest change in BMD, fat, or lean mass was compared to the baseline scan for each individual. RESULTS: Although lean and fat mass did not change significantly after injury, BMD decreased significantly. The greatest change in BMD did not occur during the acute burn hospitalization, but rather 131 days after burn injury. Changes in post-burn BMD inversely correlated with % total body surface area (TBSA) and % 3rd-degree TBSA. The magnitude of change was similar between adults and children. CONCLUSIONS: These results confirm earlier studies, suggesting that BMD can be negatively altered post-injury, with the greatest changes occurring after patients are discharged from the hospital. Although the clinical significance of these changes is not known, this study supports the need for long-term musculoskeletal assessments in burn patients and for further research to elucidate the mechanisms of burn-induced body-composition changes.     

Reduction of bone mineral density in rheumatoid arthritis: A longitudinal study

In the last decade, more accurate quantitative methods to assess bone mass in vivo have become available. We have applied these techniques to assess periodic changes of bone loss in rheumatoid arthritis (RA) patients. In this longitudinal study, 132 female RA patients were divided into two groups. The first group of 90 patients were postmenopausal, with a mean age of 60.2 years (PM group), whereas the second group of 42 patients were premenopausal, with a mean age of 42.7 years (M group). The clinical courses of these patients were followed for an average of 3 years. Bone mineral density (BMD) in the lumbar spine (L2–L4), and the femoral neck were measured by dual-energy X-ray absorptiometry (DXA), and second metacarpal bone mineral density was measured by using densitometric techniques periodically. Reduction of BMD in the lumbar spine was significant in both groups (P<0.01–0.05), but there was no statistical difference between the two groups. The BMD of the femoral neck had a tendency to decrease but this was not significant. The predictors for periodic bone loss in the PM group were aging and nutritional factors, whereas for the M group they were indices of rheumatoid arthritis disease activity.     

上海地区女性前臂骨峰值骨量的建立及其影响因素研究

目的 建立女性前臂骨不同测量部位的峰值骨量和标准差值,并探讨其可能影响因素,为周围型DEXA测定开展OP研究提供基础数据.方法 对上海市区365例21～59岁社区女性健康志愿者,采用美国NORLAND-Stratec周围型双能X线骨矿测量仪(pDEXA)测量了非优势侧(左侧)前臂远端桡骨和尺骨(Distal radius and ulna, Dist. R+U)、近端桡骨和尺骨(Proximal radius and ulna, Prox. R+U)和近端桡骨(Proximal radius, Prox. R)的BMD值,并分析了其年龄分布,建立了女性前臂骨不同测量部位的峰值骨量和标准差值.同时,以问卷调查了可能影响因素.结果 前臂骨各部位的BMD值均符合正态分布,可以采用均数±标准差(x±s)的形式表示,OP的骨量诊断标准也可以用骨量峰值的算术均数降低标准差的形式建立.45岁以前女性前臂骨不同测量部位的BMD值均随年龄增加而逐步上升,但不同年龄段BMD值的差异并不显著(P>0.05),45岁以后BMD值明显下降.前臂骨不同测量部位的骨量峰值均出现在40～44岁年龄段,前臂远端桡+尺骨(Dist. R+U)、近端桡+尺骨(Prox. R+U)和近端桡骨(Prox. R)的骨量峰值及标准差分别为(0.3717±0.0423) g/cm~2、(0.7958±0.0771) g/cm~2和(0.7802±0.0671) g/cm~2.此外,体重和怀孕次数对峰值骨量的形成有较大影响,体重过轻和怀孕次数过多均不利于峰值骨量的形成.结论 建立女性前臂骨不同部位的骨量峰值和标准差,可为周围型DEXA测定开展OP研究提供基础数据,尤其是用于高危人群筛查以确定是否需进一步开展中轴骨测量或进行药物干预.     

Bone mineral density and its correlation with clinical and laboratory factors in chronic peritoneal dialysis patients

The aim of this study was to assess the clinical and laboratory correlations of bone mineral density (BMD) measurements among a large population of patients on chronic peritoneal dialysis (PD). This cross-sectional, multicenter study was carried out in 292 PD patients with a mean age of 56 ± 16 years and mean duration of PD 3.1 ± 2.1 years. Altogether, 129 female and 163 male patients from 24 centers in Canada, Greece, and Turkey were included in the study. BMD findings, obtained by dual-energy X-ray absorptiometry (DEXA) and some other major clinical and laboratory indices of bone mineral deposition as well as uremic osteodystrophy were investigated. In the 292 patients included in the study, the mean lumbar spine T-score was −1.04 ± 1.68, the lumbar spine Z-score was −0.31 ± 1.68, the femoral neck T-score was −1.38 ± 1.39, and the femoral neck Z score was −0.66 ± 1.23. According to the WHO criteria based on lumbar spine T-scores, 19.2% of 292 patients were osteoporotic, 36.3% had osteopenia, and 44.4% had lumbar spine T-scores within the normal range. In the femoral neck area, the prevalence of osteoporosis was slightly higher (26%). The prevalence of osteoporosis was 23.3% in female patients and 16.6% in male patients with no statistically significant difference between the sexes. Agreements of lumbar spine and femoral neck T-scores for the diagnosis of osteoporosis were 66.7% and 27.3% and 83.3% for osteopenia and normal BMD values, respectively. Among the clinical and laboratory parameters we investigated in this study, the body mass index (BMI) (P < 0.001), daily urine output, and urea clearance time × dialysis time/volume (Kt/V) (P < 0.05) were statistically significantly positive and Ca × PO₄ had a negative correlation (P < 0.05) with the lumbar spine T scores. Femoral neck T scores were also positively correlated with BMI, daily urine output, and KT/V; and they were negatively correlated with age. Intact parathyroid hormone levels did not correlate with any of the BMD parameters. Femoral neck Z scores were correlated with BMI (P < 0.001), and ionized calcium (P < 0.05) positively and negatively with age, total alkaline phosphatase (P < 0.05), and Ca × P (P < 0.01). The overall prevalence of fractures since the initiation of PD was 10%. Our results indicated that, considering their DEXA-based BMD values, 55% of chronic PD patients have subnormal bone mass—19% within the osteoporotic range and 36% within the osteopenic range. Our findings also indicate that low body weight is the most important risk factor for osteoporosis in chronic PD patients. An insufficient dialysis dose (expressed as KT/V) and older age may also be important risk factors for osteoporosis of PD patients.     

Standard radial bone mineral density and physical factors in ordinary Japanese women

To prevent osteoporosis, which is expected to increase in incidence in this rapidly aging society, in recent years bone mineral density (BMD) has frequently been measured as a predisposition index. However, these measurements are made on different sites with different apparatus, and the results are independently studied by different institutions. In our present investigation, to establish the standard radius BMD as determined by dual-energy X-ray absorptiometry (DXA), we carried out a general population survey in 29 municipalities and prefectures on 11 252 locally residing females aged 15 to 83 years (mean, 35.61 ± 12.85 years). Their YAM (young adult mean) BMD was estimated at 0.664 ± 0.054 g/cm², which was almost the same as the figure given in the 1996 version of the diagnostic criteria for primary osteoporosis. We further studied the relationships of BMD to age and physical factors known to be influential to BMD. It was found that BMD was correlated negatively to age and positively to body mass index (BMI). The average values we obtained for age and physique groups appeared to have provided reliable indices for the primary prevention of osteoporosis. Received: April 26, 1999 / Accepted: July 2, 1999     

Sequential changes in periprosthetic bone mineral density following total hip arthroplasty: a 3-year follow-up

 We sequentially measured the periprosthetic bone mineral density (BMD) of the femur after cementless total hip arthroplasty, using dual-energy X-ray absorptiometry, over a 3-year period. The periprosthetic bone was divided into three regions (proximo-medial, middle, and distal to the prosthetic stem). After the insertion of a fully porous coated stem in 21 patients, the BMD was measured within 3 weeks, and 6, 12, 24, and 36 months after surgery. At 6 months, all zones showed a decrease in BMD relative to the BMD within 3 weeks, but subsequently the BMD was unchanged. The lower the BMD within 3 weeks of surgery, or the lower the body weight, the higher the percent loss of BMD at 6 months. Received: September 9, 2002 / Accepted: December 12, 2002 RID="*" ID="*" Offprint requests to: H. Ohta     

Bone mineral density in haemodialysis patients: A comparative study of dual-energy X-ray absorptiometry and quantitative ultrasound.

BACKGROUND: Quantitative ultrasound (QUS) of bone is a relatively new technique that appears to assess 'bone quality' in addition to bone mineral density. The purpose of this study was to evaluate the diagnostic potential of QUS of calcaneum and to correlate it with dual energy X-ray absorptiometry (DEXA) in chronic haemodialysis patients. METHODS: Broad-band ultrasound attenuation (BUA; dB/MHz) and speed of sound (SOS; m/s) of calcaneum and DEXA (g/cm(2)) measurements of the lumbar spine and hip were made in 39 patients. The indices obtained by either method were compared with age-and sex-matched controls. Calcaneal measurements were correlated to DEXA and relevant clinical and biochemical data of patients. RESULTS: BUA and SOS values were markedly reduced in dialysis patients compared to controls (59.1+/-13.8 vs 73.0+/-16.2 dB/MHz, P:<0.001 and 1533+/-28 vs 1560+/-29 m/s, P:=0.014 respectively). There was a moderate, but significant association between calcaneal parameters and DEXA (r=0.32-0.53, P:<0.05). Both BUA and SOS scores were inversely correlated with age (r=-0.69, P:<0.001) and duration of menopause (r=-0.74, P:<0.01). Additionally, BUA values showed a moderate negative association with serum intact parathyroid values (r=-0.38, P:=0.018). CONCLUSION: Chronic haemodialysis patients have reduced calcaneal BUA and SOS scores. QUS of the calcaneum is an easy-to-apply and radiation-free technique. It could be a useful substitute for assessment of bone density in such patients. However, further studies in large patient groups and comparisons with plasma markers of bone turnover and bone biopsy findings are needed to assess its potential place in the management of renal osteodystrophy.     

体重体成分与骨密度的关系

为了研究体成分与骨密度（ＢＭＤ）之间的关系，因体重与ＢＭＤ显著相关，体成分各个组成相加等于体重，而体成分与ＢＭＤ的关系仍不清楚。方法随机选取２０６名１６～５２岁健康的男女性汉族人，用双能Ｘ射线吸收法（ＤＸＡ）测量ＢＭＤ与体成分，进行ＢＭＤ与体重，体成分的多元线性回归分析。结果体重，瘦组织（ＬＴＭ）与男女性的ＢＭＤ显著正相关，脂肪组织（ＦＴＭ）仅对女性全身，腰椎ＢＭＤ起显著性作用。结论影响男女性ＢＭＤ的体成分中，ＬＴＭ是主要因素，ＦＴＭ仅对女性ＢＭＤ有影响。本文较全面地研究了体成分与ＢＭＤ的关系。     

Consistency of low bone density across bone sites in SAMP6 laboratory mice

The development of bone densitometry has made it clear that there are discrepancies in bone density at various measurement sites in a given individual. This study examined the consistency of bone density measurements across various sites in a strain of laboratory mouse (senescence-accelerated mouse; SAM). A systemic evaluation of the bone density was performed by dual-energy X-ray absorptiometry (DXA) on SAMP6 (P6) mice, a strain with low peak bone density, as measured by microphotodensitometry of the femoral bones, whereas the SAMP2 (P2) and SAMR1 (R1) strains have high peak bone density. We modified Jilkas method to more comprehensively measure the whole body and additional regions of interest (ROIs; head, right foreleg, left foreleg, right hindleg, left hindleg, spine, and tail). The age-related changes in the total (whole-body) BMD showed a common pattern among the strains studied, and the peak value was seen at 4 months old. P6 showed the lowest peak BMD. A detailed comparison of the bone density between P6 and P2 at the age of 4 months revealed significantly lower regional BMD values for P6 in all seven ROIs. The strain difference in BMD could not be attributed to a difference in size. In conclusion, P6 mice showed low bone density not only in their femurs but also in the subregions and over their entire body. This strain can be potentially useful in the investigation of the genetic basis of senile osteoporosis.     

Effects of skeletal size of the lumbar spine on areal bone density,volumetric bone density,and the diagnosis of osteoporosis in postmenopausal women in China

To understand the effects of skeletal size of the lumbar spine on areal bone mineral density (aBMD), volumetric bone mineral density (vBMD), and the diagnosis of osteoporosis in postmenopausal women, we measured the projected bone area, bone mineral content (BMC), aBMD, and vBMD at the anteroposterior and lateral lumbar spines in a population of 1081 postmenopausal Chinese women, 42 to 86 years of age. The results indicated that, at the anteroposterior and lateral lumbar spine, there were significant positive correlations between bone area and both BMC (r = 0.606; P = 0.000 and r = 0.610; P = 0.000) and aBMD (r = 0.270; P = 0.000 and r = 0.182; P = 0.000), but not vBMD (r = –0.055; P = 0.000 and r = 0.000; P = 0.929). When bone area at the anteroposterior spine changed by ±1 SD, the BMC, aBMD, and vBMD correspondingly changed by 28.2%, 10.1%, and 1.69% on the basis of their respective means. When a variation of ±1 SD was observed in bone area at the lateral spine, BMC and aBMD, correspondingly changed by 25.9% and 6.18% on the basis of their respective means, while vBMD indicated no change. Through comparisons among large-, intermediate-, and small-bone area groups, significant differences were found in the means of subjects heights, weights, BMC, and vBMD at the anteroposterior and lateral lumbar spines, as well as in the detection rates of osteoporosis by aBMD (P = 0.000). Detection rates of osteoporosis by aBMD at the anteroposterior spine and by aBMD at the lateral spine, and by vBMD were 44.1%, 55.5%, and 49.7%, respectively, in the total population; 31.4%, 41.7%, and 53.7%, respectively, in the large-bone area group; 43.3%, 55.9%, and 50.5%, respectively, in the intermediate-bone area group; and 61.7%, 70.0%, and 42.5%, respectively, in the small-bone area group. No significant differences were found in the detection rates of osteoporosis by vBMD among the groups. The results of multiple linear regression revealed that the major factors influencing skeletal size and aBMD of the lumbar spine were height and weight. Therefore, in menopausal women of the same ethnic group and age, the skeletal size of the lumbar spine would have significant influence upon aBMD and the diagnosis of osteoporosis, i.e., the larger the spinal size, the greater the aBMD and the lower the osteoporosis detection rate, while, conversely, the smaller the skeletal size, the smaller the aBMD and the higher the osteoporosis detection rate. When we use aBMD of the lumbar spine to diagnose osteoporosis in a population with different body sizes, we need to take this body size difference into account. When we use vBMD to diagnose osteoporosis, the effect of body size on BMD will diminish.     

Prevalence of osteoporosis and reference data for lumbar spine and hip bone mineral density in a Korean population

The aims of this study were to establish reference data for bone mineral density (BMD) at central skeletal sites using Lunar dual-energy X-ray absorptiometry (DXA), and to estimate the age-and sex-specific prevalence of osteoporosis in a Korean population. We performed a population-based, cross-sectional study. The subjects were 4148 (1810 men and 2338 women) Korean adults, aged 20–79 years. The BMD for central sites (lumbar spine, femoral neck, trochanter, and Ward’s triangle) were measured by DXA. The standardized prevalence of osteoporosis among individual aged 50–79 years in lumbar spine, femoral neck, Ward’s triangle, and trochanter was 40.1%, 12.4%, 28.4%, and 4.4% in women and 6.5%, 5.9%, 3.7%, and 1.6% in men, respectively. In women, peak BMD occurred in the age range 40–49 years for the femoral neck and trochanter, 30–39 years for the lumbar spine, and 20–29 years for Ward’s triangle. In men, peak BMD values were observed at 20–29 years for all measured sites. This study establishes a normative database for BMD at central skeletal sites using dualenergy X-ray absorptiometry and provides more reliable information on the prevalence of osteoporosis in Korea.     

天津地区1695例骨密度调查研究

目的 调查天津地区部分人群骨密度，建立天津地区骨密度参考值数据库，为骨质疏松预防、诊断、治疗提供科学依据。方法 应用双能X线骨密度仪对天津地区1695例人群进行骨密度检测、分析。结果 天津地区男女骨密度峰值均在25～30岁年龄组，女性50岁、男性60岁以后骨密度丢失率、患病率升高，女性65～70岁年龄组骨密度均值城乡差异有显著性。结论 天津地区人群骨密度参考值，为骨质疏松的临床研究及流行病学比较奠定基础。     

Correlation between bone mineral density and intervertebral disk degeneration in pre- and postmenopausal women

 The purpose of this study was to investigate the relationship between intervertebral disk degeneration and bone mass. Magnetic resonance imaging was performed to evaluate lumbar disk degeneration according to Thompson's classification (grades 1 and 2, normal disk; grades 3, 4, and 5, degenerated disk), and bone mineral density (BMD) in the lumbar vertebrae, radius, and calcaneus was measured by dual-energy X-ray absorptiometry for 90 women (22–74 years old). The relationship between the grade of intervertebral disk degeneration and the BMD (Z score) was analyzed in pre- and postmenopausal women. In premenopausal women, BMD was significantly higher at all measured sites in the degenerated disk group judged at the L5–S1 level than in the normal disk group (P < 0.05). In postmenopausal women, BMD was significantly higher at the anteroposterior L2–L4, lateral L3, and calcaneus in the degenerated disk group judged at the L2–L3 level than in the normal disk group (P < 0.05). BMD at the anteroposterior L2–L4 and calcaneus was significantly higher in the degenerated disk group judged at the L3–L4 level than in the normal disk group (P < 0.05). In conclusion, the BMD of not only the lumbar vertebrae but also the calcaneus and radius was mutually related to lumbar intervertebral disk degeneration from an early stage of degeneration. Received: May 16, 2002 / Accepted: July 31, 2002 Offprint requests to: Y. Nanjo     

北京地区3859名体检人群骨密度调查及骨量异常患病率分析

目的调查北京地区健康体检人群骨密度的情况以及骨量减少和骨质疏松的患病率,为骨质疏松症的防治提供参考。方法选择2017年1月至2018年12月在中日友好医院健康体检中心进行健康体检的人群,排除继发性骨质疏松症及其他影响骨代谢的因素,共3859名。其中男性2067名,女性1792名。年龄20~83岁,平均年龄(51.29±11.18)岁,按性别及年龄每10年一组。采用美国GE公司的LUNAR Prodigy双能X线骨密度仪测量受试者腰椎1~4正位及股骨颈和全髋的骨密度。分析各组不同部位骨密度情况及骨量异常(包括骨量减少和骨质疏松)的患病率。采用SPSS 22.0统计软件进行分析,以P<0.05为差异有统计学意义。结果①男性腰椎1~4骨密度峰值在20~29岁,股骨颈和全髋骨密度峰值在30~39岁。女性各部位骨密度峰值均在30~39岁。②随年龄增长,男性和女性骨量异常患病率均呈上升趋势,50岁以上女性骨量异常患病率显著上升,明显高于同年龄组男性。③30~59岁男性和女性腰椎骨量异常患病率均明显高于髋部;70岁以上男性和60岁以上女性髋部骨量异常患病率明显高于腰椎。结论中老年人群尤其是绝经后女性是骨质疏松症的高危人群;老年人群的骨质疏松筛查可以考虑选择髋部骨密度为主。     

Bone mineral density and turnover in patients with acromegaly in relation to sex, disease activity, and gonadal function

Acromegaly is a rare disease caused by growth hormone (GH) hypersecretion. GH and insulin-like growth factor-I (IGF-I) exert anabolic activity in bones. Nevertheless, bone mineral density (BMD) loss is not uncommon in patients with acromegaly. It is assumed to be due to hypogonadism associated with the acromegaly. The aim of the study was to examine BMD at various skeletal sites and bone turnover and to assess the influence of impaired gonadal function and disease activity on BMD and turnover changes in acromegaly. A total of 62 patients were studied (40 women, 22 men). Among the women, 22 had active disease and 18 were cured; 16 women had normal gonadal function, and 24 were hypogonadal. Altogether, 12 men presented with active acromegaly, and 10 were cured; normal gonadal function was found in 10 men, and hypogonadism was diagnosed in 12 men. Controls were 30 healthy subjects. Densitometry using dual-energy X-ray absorptiometry of the lumbar spine, proximal femur, forearm, and total body was carried out. Bone turnover was studied based on serum osteocalcin, C-terminal collagen type 1 crosslinks, and bone alkaline phosphatase concentration. A disadvantageous effect of acromegaly on bone density was associated with hypogonadism in the distal radius (in women), the proximal femur (in men), and the total body (both sexes). An anabolic effect of GH during active acromegaly was present in the proximal femur only in men. We confirmed increased bone turnover in the presence of acromegaly, and these changes were similar regarding the activity of the disease and the gonadal status.     

Establishment and evaluation of bone mineral density reference databases appropriate for diagnosis and evaluation of osteoporosis in Chinese women

 This study was designed to establish Bone Mineral Density (BMD) Reference Databases for multiple skeletal sites appropriate for the diagnosis and evaluation of osteoporosis (OP) in Chinese women. We recruited 2702 healthy Chinese women, 5–96 years of age, for BMD assessment. BMD values at multiple skeletal sites including anteroposterior (AP) and lateral (Lat) lumbar spine, hip, and forearm were measured by dual-energy X-ray absorptiometry (DXA) using a QDR 4500A device; results were analyzed according to age group using eight regression models. BMD Reference Databases (CWD) were established according to the best regression equation and compared with Hologic reference databases for “Oriental Women” (OWD). Results indicated that the cubic regression model was superior to the quadratic, linear, logarithmic, and exponential regression models, etc. for our purpose, with a determinate coefficient (R ²) of 0.363–0.650 (P = 0.000). We included 1636 female patients, aged 35–86 years, in our tests. In comparison with Hologic Reference Databases, the mean detection rate of OP in the newly established BMD Reference Databases for Chinese Women (CWD) was 16.0% ± 2.68% lower (range, 13.7%–20.5%) at the AP spine, 16.8% ± 11.0% lower (range, 3.5%–32.8%) at the Lat spine (except for L4), 18.7% ± 4.6% lower (range, 12.6%–24.2%) at the hip, and 14.3% ± 6.9% higher (range, 4.7%–24.3%) at the forearm. The difference in detection rates for OP was significant between the two reference databases (P = 0.000), which was consistent with the differences in peak BMD values and the biological variability between them. Based upon our data, we confirmed that the Hologic BMD Reference Databases for Oriental Women (OWD) were not suitable for the diagnosis of OP in Chinese women; the BMD Reference Databases for Chinese Women (CWD) established in this study would provide reliable diagnostic standards for detection of OP in the women of South China. Received: July 9, 2002 / Accepted: December 5, 2002 Offprint requests to: X.-P. Wu     

Bone loss after kidney transplantation: a longitudinal study in 115 graft recipients

BACKGROUND.: Bone loss is an important problem in renal transplant recipientsimmediately after surgery. No data are available about the boneloss beyond the first post-transplantation year. METHODS.: In a longitudinal, uncontrolled observational study bone mineraldensity (BMD) was measured by dual X-ray absorptiometry in 115renal graft recipients starting at different times after transplantation(0–20 years after transplantation) with a follow-up timeof 12 months. RESULTS.: A total of 56 patients showed a reduction of BMD during theobservation period. Bone loss depended on the time after transplantation.Mean reduction of BMD at lumbar spine was 7±10%, 1±9%during the first and second postoperative year. Beyond the thirdyear bone mineral density did not change or even increased slightly(0±4% during 3–5th year, 1±6% during 6–10thyear and 2±4% during 11–20th year after transplantation).Decrease of BMD correlated with a higher mean daily prednisonedosage (P<0.001), a higher cumulative prednisone dose (P<0.01),a more frequent and more steroid-resistant rejection (P<0.001)and a higher initial parathyroid hormone level (P<0.001).Patients with 25-OH-cholecalciferol therapy (P<0.05) or morephysical activity (P<0.05) had a smaller bone loss. CONCLUSIONS.: Reduction of BMD after transplantation is highest within thefirst post-transplant year. The effects of acute graft rejection,prednisone dosage and initial parathyroid hormone level arepredominant among the multiple factors associated with pronouncedbone loss.     

减肥手术对骨密度的影响

目的通过双能X线吸收测定法(DXA)测量超重或肥胖患者的骨密度,对比分析减肥手术前后骨密度的改变情况。方法根据入选标准及排除标准纳入需要进行减肥手术治疗的超重或肥胖患者,手术前检测基线观察指标,其中包括简易人体测量参数、骨密度。然后,对纳入的患者行腹腔镜下胃旁路术或腹腔镜下袖状胃切除术,术后4~6月复查基线观察指标,重点对比分析减肥手术前后骨密度的改变情况。结果 1减肥手术后,体重、BMI、腰围均明显减少,差异有统计学意义(P0.05)。2减肥术后全身骨密度及髋部骨密度均有降低(P0.05)。结论腹腔镜下胃旁路术及腹腔镜下袖状胃切除术都是有效的减肥术式,骨密度有不同程度的降低,术后应注意骨密度的维护。     

Measurement of periprosthetic bone mineral density after cementless hip arthroplasty by dual energy X-ray absorptiometry: Longitudinal and cross-sectional evaluation

To clarify changes in bone mass around a femoral prosthesis, periprosthetic bone mineral density (BMD) was measured by dual energy X-ray absorptiometry (DXA) in 60 patients after unilateral cementless hip arthroplasty. Changes in BMD were evaluated by cross-sectional analysis in all patients and by longitudinal analysis in 26 patients who were available for measurement from 1 month to 2 years after surgery. The mean reproducibility of BMD measurements was within 1.74% in vivo. Periprosthetic BMD began to decrease early after surgery, and although it recovered temporarily within 1 year, it did not return to the level of the 1st month even after 2 years. BMD was reduced by 30.4% in the whole periprosthetic region compared with the contralateral untreated femora 4–7 years after surgery. The reduction in BMD was remarkable around the proximal part of the stem, especially in zone 7 (44.7% reduction 4–7 years after surgery). Significant positive correlations were observed between the low level of the preoperative cortical remodelling index and the reduction in BMD and between the preoperative femoral BMD and the reduction in BMD, indicating that the postoperative bone loss was greater in patients who preoperatively showed quantitative and qualitative deterioration of the femur. Abstracts of this paper were presented at the 66th and 67th Annual Meeting of the Japanese Orthopaedic Association, the 19th Conference of Société Internationale de Chirurgie Orthopédique et de Traumatologie (SICOT), and the 20th Conference of the Japanese Hip Society