Bone mineral density measured by dual-energy X-ray absorptiometry in healthy finnish women

Summary A cross-sectional study of 351 healthy Finnish women aged 20–76 years was done to establish reference values of bone mineral density (BMD) using dual-energy X-ray absorptiometry (DEXA). The effects of age and of several physical and lifestyle factors on BMD of the lumbar spine and proximal femur (femoral neck, trochanter, and Ward's triangle area) were investigated. Altogether 58 women were excluded from the final analysis due to significant spinal osteoarthritis or other diseases or drugs known to influence calcium or bone metabolism. The precision of the method was 0.9, 1.2, 2.7, and 2.4% in the lumbar, femoral neck, Ward's triangle and trochanter area, respectively. Lumbar BMD was increased by 30% (P<0.001) in 15 patients with osteoarthritis (21% of women 50 years or older), but it was apparently unaffected in 5 cases with aortic calcification. Except for the trochanter area, BMD diminished along with age, and this was significant after the menopause. The peak of mean BMD was observed at the age of 31–35 years in the spine and at the age of 20–25 years in the femoral neck and Ward's triangle. BMD was in a positive relationship to weight both in premenopausal and postmenopausal women and to the use of oral contraceptives in premenopausal women and to that of estrogen replacement therapy in postmenopausal women. Labors and pregnancies had a weak positive effect on BMD in premenopausal women. As compared with nonusers premenopausal women who had used alcohol showed a slightly decreased BMD of Ward's triangle. In postmenopausal women there was a positive correlation between alcohol intake and BMD.     

The relationship between endogenous estrogen,sex hormone-binding globulin,and bone loss in female residents of a rural Japanese community: the Taiji Study

 The aim of this study was to clarify the relationship between endogenous estrogen, sex hormone-binding globulin (SHBG), and bone loss in pre-, peri-, and postmenopausal female residents of Taiji, a rural Japanese community. From a list of inhabitants aged 40 to 79 years, 200 participants—50 women in each of four age decades—were randomly selected, and baseline bone mineral density (BMD) at the lumbar spine and proximal femur were measured by dual-energy X-ray absorptiometry in 1993. Total estradiol (total E2) and SHBG were measured, and SHBG-unbound E2 (UBE2) was calculated using SHBG and the percent SHBG-unbound fraction ratio. BMD was measured again 3 years later, in 1996. Participants with ovariectomy or hysterectomy were excluded, and the remaining participants were categorized into four groups: premenopausal (n= 38), perimenopausal (n= 14), postmenopausal group 1 (5 years or less since menopause; n= 18), and postmenopausal group 2 (6 years or more since menopause; n= 74). The mean value of total E2 was highest in the premenopausal group (49.1 pg/ml), followed by the perimenopausal group (26.4 pg/ml), and the postmenopausal groups (0.83 pg/ml in postmenopausal group 1 and 0.96 pg/ml in postmenopausal group 2). The means for UBE2 showed the same pattern across the groups. After the multiple regression analysis of BMD at follow-up and endogenous estrogens, in premenopausal women, there were no significant associations between BMD at follow-up and serum total E2 and UBE2. In perimenopausal women, however, serum total E2 and UBE2 were significantly correlated with trochanteric BMD at follow-up (P < 0.05); and in postmenopausal group 2, they were significantly correlated with lumbar spine and Ward's triangle BMD at follow-up (P < 0.001 at lumbar spine, P < 0.05 at Ward's triangle). Concerning the association between BMD at follow-up and SHBG, in the premenopausal group, serum levels of SHBG were negatively correlated with BMD at the femoral neck (P < 0.05). In regard to partial regression coefficients for the change rates of BMD over 3 years and serum estrogens and SHBG concentrations, in perimenopausal women, UBE2 was correlated with the change rate of BMD at Ward's triangle (P < 0.05), and in postmenopausal group 1, serum levels of SHBG were significantly negatively related to change in BMD at the trochanter (P < 0.01). No other relationships with change in BMD were observed at any sites. These findings suggest that serum E2, UBE2, and SHBG levels differentially predict BMD levels in groups of differing menstrual status. It would, however, be difficult to predict bone loss in middle-aged and elderly Japanese women over a 3-year period using these indices alone. Received: November 29, 2001 / Accepted: February 28, 2002     

The effect of age and menopause on bone mineral density of the proximal femur

Although the menopause has been associated with increased bone loss at several skeletal sites, it has not previously been noted in the hip, yet estrogen therapy has been reported to reduce the incidence of hip fractures. We investigated the effect of age and menopause on bone loss in the proximal femur by measuring bone mineral density (BMD) of the femoral neck, Ward's triangle, and trochanter by dual-photon absorptiometry in 263 normal women aged 20-84. Multiple regression analyses revealed a significant decrease in BMD of the femoral neck and Ward's triangle with age in both pre- and postmenopausal women (p less than 0.001). In the trochanter the decrease with age was significant only in postmenopausal women (p less than 0.001). Further analysis revealed that BMD decreased faster at all sites in the early postmenopausal years. During the first 6 years postmenopause, the decrease in BMD of the femoral neck and trochanter was 3-10 times higher than the change in the decade prior to menopause. About 20% of the lifetime femoral neck loss and 30% of the trochanteric loss occurred in the early postmenopausal period. It is concluded that both age and menopause are major determinants of BMD in the proximal femur. These findings could explain why estrogen therapy has been reported to prevent hip fracture. The rapid early postmenopausal loss in BMD of the proximal femur demonstrates the importance of starting estrogen replacement therapy immediately after menopause for maximum effect.     

Dissimilar Spine and Femoral Z-Scores in Premenopausal Women

The purpose of this study was to determine if differences exist in premenopausal women between z-scores for lumbar spine and proximal femoral bone mineral densities (BMD). Participants were 237 women ranging in age from 20 to 45 years. BMDs of the lumbar spine and proximal femur (femoral neck, Ward's area, and trochanter) were assessed using dual-energy X-ray absorptiometry (Lunar DPX). Mean (±SD) age, height, and weight of the participants were 29.4 ± 6.9 years, 164.4 ± 6.1 cm, and 64.9 ± 12.1 kg, respectively. Lumbar spine BMD and BMD at the femoral neck, Ward's area, and trochanter were significantly correlated with large SEEs (r = 0.59–0.65; SEE = 0.09–0.11). No positive correlation with age and BMD at any site was seen in this population but a significant negative correlation with age was seen in the proximal femur beginning at age 30. Twenty to 24% of the 20–29-year-olds exhibited a difference in z-scores of greater than 1 between the spine and sites in the proximal femur. This percentage increased to 32–46% in the 30–45-year-olds but the nature of the observed differences changed. The differences in spine and proximal femoral z-scores that are seen in the older age group appear to be the result of the earlier onset of bone loss in the proximal femur rather than an initial difference in peak bone mass which has been maintained. Received: 28 August 1996 / Accepted: 25 April 1997     

Bone density in white Brazilian women: Rapid loss at the time around the menopause

Dual energy x-ray absorptiometry (DXA) was used to measure bone mineral density (BMD) of the lumbar spine and proximal femur (neck, Ward's triangle, and trochanter) in 417 normal women (aged 20–79) living in São Paulo, Brazil. Bone density decreased with age at all sites. At the spine, the greatest decrease occurred during the sixth decade, with an average 11.4% bone loss compared with the previous decade. Stratifying the subjects according to menopausal status revealed that the fastest bone occurred at the time around the menopause (ages 45–60) when the rate of bone loss (-0.66%/year) was almost twice as rapid as in postmenopausal women (-0.39%/year). Although significant linear rates of bone loss were detected in all proximal femur sites before the menopause, a menopause-dependent pattern was less evident that at the spine. Lifetime rates of bone loss at the appendicular skeleton were-0.43,-0.62, and-0.35%/year at the femoral neck, Ward's triangle, and trochanteric area, respectively. After the menopause, BMD declined with menopausal age at all sites, although the rate of bone loss was faster at the femoral neck (-0.62%/year) and Ward's triangle (-0.84%/year) than at the spine-0.49%/year). The results are consistent with the notion that in women, the fastest bone loss occurs at the time round the menopause, most likely consequent to ovarian failure; and that faster rates of bone loss are detected at the proximal femur than at the lumbar spine in late postmenopausal women.     

Dual-energy X-ray absorptiometry in normal women: A cross-sectional study of 717 finnish volunteers

The bone mineral density (BMD) of the lumbar spine and proximal femur was measured using dual-energy X-ray absorptiometry in 717 healthy women aged 20–70 years. The maximal mean BMD was found at the age of 35–39 years in the spine and at the age of 20–24 in the femoral neck and Ward's triangle. No significant change in lumbar BMD was found from the age of 20 to 39 years. The spinal BMD values were relatively stable from age 20 to 39 years, whereas a linear decrease in BMD in the femoral neck and Ward's triangle was already apparent in the youngest age group (20–24 years). The major fall in BMD in all sites was related to the menopause. The overall decreases in BMD from the peak values to those at age 65–70 years were 20.4%, 19.0% and 32.6% in the lumbar spine, femoral neck and Ward's triangle, respectively. The correlation of trochanteric BMD with age was poor. BMD was positively correlated with weight in all measurement sites. Nulliparity was found to be a risk factor for osteoporosis. The present study confirmed that the menopause has a significant effect not only on spinal BMD but also on femoral BMD. Lumbar BMD was lower and BMDs in the proximal femur were higher in Finnish women than in white American women. This emphasizes the importance of national reference values for BMD measurements.     

Hip fracture patients have generalized osteopenia with a preferential deficit in the femur

Bone density was measured in 31 white women with hip fractures by single- and dual-photon absorptiometry at the radius, lumbar spine and proximal femur. The mean age was 71.4 years. Comparison with premenopausal normals revealed Z-scores as follows: radius, –1.75; spine, –1.45; femoral neck, –2.40; Ward's triangle, –2.41; and trochanter, –1.42. These values altered when calculated for the patient's age by the use of sex-and race-specific regressions against age in a healthy, non-fracture population. The age-corrected Z-scores were as follows: radius, –0.09; spine, –0.18; femoral neck, –0.79; Ward's triangle, –0.44; and trochanter, –0.80. Thus, although our patients had absolute osteopenia at all skeletal sites when compared with young normals, when compared with age-matched normals (relative osteopenia) the only site with a noticeable deficit was the femur. Interpretation of the extent of osteopenia by comparison with young normals may lead to different conclusions than when an age-matched population is used. Patients with hip fractures had a preferential deficit in density of the femur when compared with normal women of their age.     

老年股骨颈骨折骨密度、Singh指数的研究

目的研究骨密度和Singh指数在衡量股骨近端骨强度和预测股骨颈骨折中的意义.方法对21名60岁以上、因轻度创伤所致新鲜股骨颈骨折老年人进行股骨近端骨密度、Singh指数及Ward三角矿化骨体积进行测量.结果本组患者股骨近端骨密度减少规律,Ward三角>股骨颈>股骨粗隆,骨密度减少的下限(±s)是股骨颈1.14SD、粗隆部0.35SD、Ward三角2.04SD;Singh指数4级以下(含4级)20名(95.2%);Singh指数与MBV呈正相关(r=0.517P<0.05),与粗隆部骨密度及减少的标准差呈正相关(r=0.457,0.474P<0.05).结论骨密度较峰值骨量减少的标准差数在股骨颈大于1.14、粗隆部大于0.35、Ward三角大于2.04,加上Singh指数低于4级(含4级)提示股骨颈骨折的危险性明显增高.     

Symmetry of Bone Mineral Density at the Proximal Femur with Emphasis on the Effect of Side Dominance

The symmetry and effect of side dominance on the bone mineral density (BMD) of proximal femur was evaluated in 266 normal Chinese women with a dual photon absorptiometer (DPA, Norland 2600). The BMDs of the femoral neck, trochanter, and Ward's triangle at the proximal femur in the dominant leg (BMDd) were compared with those of the nondominant side (BMDn). The linear regression of BMDd and BMDn of the corresponding regions at the proximal femur showed a good correlation (r = 0.893–0.941, SEE = 0.052–0.062 g/cm²). The paired difference of proximal femoral BMD was −0.002 ± 0.062 g/cm² for the femoral neck, 0.003 ± 0.054 g/cm² for the trochanter, and 0.008 ± 0.062 g/cm² for the Ward's triangle. The ratio of asymmetry for femoral neck BMD was mean ± SD =−0.4 ± 7.8%, for trochanter 0.6 ± 8.1%, and for the Ward's triangle 1.3 ± 9.7%. Both paired difference and ratio of asymmetry between BMDd and BMDn were approximately normally distributed, with a mean ± 2 SD ranging from −0.126 to 0.122 g/cm² for paired difference and −16.0% to 15.2% for the ratio of asymmetry in the femoral neck. These data revealed that dominance had little effect on the proximal femur BMDs. However, the wide range of paired difference and ratio of asymmetry of the proximal femur BMD in the normal individuals should be considered in the interpretation of the proximal femoral BMD. Received: 26 July 1996 / Accepted: 23 April 1997     

Spine and femur BMD by DXA in patients with varying severity spinal osteoporosis

Summary Bone mineral density (BMD) at the lumbar spine, femoral neck, trochanteric region, and Ward's triangle was measured using dual-energy X-ray absorptiometry (DXA) in 118 women with osteoporotic vertebral collapse (average age 65 years), divided into four groups according to numbers and SD of vertebral deformation below norms: group 1:-3SD deformations only; group 2: one-4SD deformation; group 3: two-four-4SD deformations; and group 4: 5 or more-4SD deformations. There were no significant differences between the groups. Results were compared with those from 80 premenopausal (average age 32 years, range 20–40 years) and 109 postmenopausal normal women (average age 64, range 60–70 years). Mean BMD in osteoporotic group 1 was lower than premenopausal normal women by 32% at the lumbar spine, 31% femoral neck, 30% trochanteric region, and 44% at Ward's triangle, and postmenopausal controls by 17% lumbar spine, 16% femoral neck, 17% trochanter, and 14% Ward's triangle. There was a clear trend to reduction in mean BMD between osteoporotic groups 1 and 4 at all four measured sites with significant differences at the spine of 0.102 g/cm² (P<0.01) and Ward's triangle 0.059 g/cm² (P<0.01). When compared with premenopausal controls, there was a reduction in mean BMD between osteoporotic groups 1 and 4 of 10% at the lumbar spine, 7% femoral neck, 8% trochanteric region, and 13% Ward's triangle. Receiver operating characteristic analysis showed no significant differences in diagnostic sensitivities among the four measured sites for vertebral fractures. We conclude from this crosssectional data that the majority of bone loss in spinal osteoporosis occurs before the onset of fractures.     

Right and left proximal femur analyses: Is there a need to do both?

The purpose of this study was to determine if differences existed between right and left proximal femur bone mineral density (BMD) in a group of women. Participants for the study were 198 women ranging in age from 16 to 73 years. Bone mineral densities of both proximal femurs (femoral neck, Ward's area, and trochanter) were assessed using dual energy X-ray absorptiometry (Lunar DPX). Mean (±SD) age, height, and weight of the participants were 32.9±18 years, 164±7.4 cm, and 64.9±12.1 kg, respectively. Significant differences between right and left femoral BMDs were found only in the trochanter. Overall, mean differences in BMD were low (neck=0.7%, Ward's =0.2%, and trochanter=1.9%) but individual variations were as high as 22%. Based on BMD z-scores of <−1.0, 84 women were classified as “at risk” for osteoporosis. When right and left z-scores were compared, misclassifications of at risk women were 4, 15, and 11 for neck, Ward's area, and trochanter, respectively. In conclusion, analyses of both right and left proximal femurs may not be necessary for either the researcher or the clinician.     

Bone density of the radius,spine, and hip in relation to percent of ideal body weight in postmenopausal women

Summary Bone mineral content (BMC) and bone mineral density (BMD) of the spine (L2–L4) and hip (at femoral neck, Ward's triangle, and greater trochanter sites) were determined by dual-photon absorptiometry (DPA), and of the radius by single-photon absorptiometry (SPA) in healthy postmenopausal women aged 40–70 years. The relationships of BMC and BMD to years since menopause were examined separately in 97 women who were above 115% of ideal body weight (IBW) and in 128 women below. The heavier women had significantly greater mean BMC and BMD at each site than did the normal-weight women. In the normal-weight women, there was a significant negative correlation between BMD and years since menopause at each measurement site except the greater trochanter. In the obese women, BMD decreased with increasing years since menopause at the radius site only and BMC declined with increasing years after menopause at the hip (femoral neck and Ward's triangle region) as well as the radius. Thus, body size is a significant determinant of BMD in this population. The pattern of loss of BMD from Ward's triangle and femoral neck regions of hip are similar to that of the spine. The BMC and BMD findings in the hip suggest that remodeling occurs at this weight-bearing site which has a favorable effect on bone strength.     

绝经后股骨颈骨折股骨头骨铁含量、血清铁蛋白与骨密度相关性研究

 目的 探讨女性绝经后股骨颈骨折股骨头骨铁含量、血清铁蛋白与髋部骨密度的相关性。方法 2010年6月至2013年3月,收集156例股骨颈骨折行髋关节置换的绝经后女性患者资料,年龄56~92岁,平均(72.40±8.97)岁;按每10岁年龄段分组,共分5组,即≤ 60岁组、61~70岁组、71~80岁组、81~90岁组、≥91岁组。患者入院后第2天留空腹血清标本测定血清铁蛋白和骨代谢指标;对髋关节置换术后留取的股骨头组织行骨铁含量检测和骨铁染色,术后第10天行髋部和腰椎骨密度(DXA)检测。结果 5组之间骨铁、血清铁蛋白、转铁蛋白、总铁结合力、Ⅰ型原胶原氨基端延长肽、Ⅰ型胶 原C端肽β降解产物、髋部和L1~4骨密度存在组间差异。髋部和L1~4骨密度随年龄增加而下降,骨铁和血清铁蛋白随年龄增 加而升高,骨铁和血清铁蛋白检测值均在81~90岁年龄组达到峰值,156例患者的平均骨铁量为96.81 μg/g,平均血清铁蛋白为235.66 μg/L。156例患者中,血清铁蛋白＞200 μg/L的患者为100例(100/156,64.1%)。骨铁、血清铁蛋白、年龄、体重指数可进入髋部骨密度回归模型,股骨颈R2=0.443,Wards三角R2=0.397,大转子R2=0.322,全股骨R2=0.379;控制年龄、体重、体重指数等因素,骨铁和血清铁蛋白与髋部骨密度呈负相关,与腰椎骨密度无明显相关性。结论 发生股骨颈脆性骨折的绝经后女性患者体内存在铁蓄积,股骨头骨铁含量随年龄增加而升高,骨铁增加和血清铁蛋白升高可能是髋部骨密度下降的独立危险因素,铁蓄积与绝经后骨质疏松症存在相关性。     

Spine and femur densitometry at the menopause: Are both sites necessary in the assessment of the risk of osteoporosis?

Summary The aim of our study was to compare the results provided by the measurement of vertebral and femoral bone mineral density (BMD) for assessing the individual risk of osteoporosis as defined by either low BMD and/or rapid bone loss. Vertebral and femoral BMD were measured twice at a mean interval of 21 months in 85 normal, early post-menopausal women who had passed a natural menopause 6 months to 3 years previously. According to the measurement site, 36% (spine), 29% (femoral neck), 35% (Ward's triangle), and 25% (trochanter) fall in the at risk category, defined by a BMD value of 1 SD or more below the normal values for premenopausal women. Based on vertebral BMD, 39–48% of the women at risk had a normal femoral BMD. On the other hand, 24–37% of the women classified at risk based on femoral BMD maintained a low risk at the vertebral level. The annual rate of bone loss was significantly greater for the Ward's triangle (-2.7±3.8%) and femoral neck (-2.1±2.5%) than for the spine (-1.5±2.1%) and trochanter (-1.5±3.4%). There was a significant relationship between the rate of loss measured at the spine and femoral levels (r=0.34–0.58). Among the 21 women with a rapid vertebral bone loss, 48–67% had a low bone loss at the femoral level and vice versa. The ratio between mean rate of loss and the precision of the measurement sites was greater for the spine (1.6) compared with the femur (1.1–0.71). Our results indicate that vertebral and femoral BMD measurements produce discordant results in assessing the individual risk for osteoporosis.     

Bone mineral density in Norwegian premenopausal women

The aims of this study were: 1) to determine bone mineral density (BMD) in different age groups, 2) to determine the prevalence of low BMD, and 3) to determine the possible association between BMD and a number of risk factors in Norwegian premenopausal women. BMD of the lumbar spine (L₂–L₄), total body, and the hip (total femur, femur neck, and trochanter) were measured using dual-energy X-ray absorptiometry (Prodigy, Lunar) in 145 randomly selected women aged 13–39 years. Information on other factors thought to influence BMD was obtained through questionnaire and a clinical interview. The group aged 25–29 years had the highest mean BMD in the total body, lumbar spine, and total femur while the group aged 13–19 years had the highest mean BMD in the femur neck and the trochanter. The mean BMD values of Norwegian premenopausal women were 3.4–5.1% higher than US/European reference data (P<0.05). Five percent of the study sample aged 20–39 years were defined with low BMD (Z-score <–2) using the standard values from this study. Weight-bearing physical activity, body weight, body height, and age were positively associated with BMD, whilst menstrual dysfunction and previous pregnancy were associated with lower BMD in some of the measurement sites. The results show that the factors associated with BMD are extensive, and the strategies to prevent low BMD have to be multifactorial. A follow-up study should be conducted on the study sample to investigate actual mean BMD values and BMD changes through time.     

Differential effects of estrogen treatment on bone mineral density of the spine,hip, wrist and total body in late postmenopausal women

It is commonly believed that estrogen is effective only in preventing menopause-related loss of bone mineral. However, recent studies found significant increases in bone mineral density (BMD) of the spine in response to estrogen, particularly in older women. The degree to which estrogen can restore BMD of the hip is uncertain. In the present study, changes in BMD of the lumber spine (L2–4), hip (neck, trochanter and Ward's triangle), wrist (ultradistal) and total body in response to 1 year of hormone replacement therapy (HRT) were evaluated by dual-energy X-ray absorptiometry (DXA) in women 10 or more years past menopause. Twelve women, aged 61–74 years, received conjugated estrogens 0.625 mg and cyclic medroxyprogesterone acetate 5 mg; 12 women who did not receive HRT were controls. Calcium intake was adjusted to approximately 1500 mg/day in all subjects. There were no differences between the groups in BMD prior to treatment. Increases in BMD of the lumbar spine (mean±SD, 0.041±0.030 g/cm²), hip (neck, 0.019±0.018 g/cm²; trochanter, 0.017±0.012 g/cm²; Ward's triangle, 0.026±0.029 g/cm²) and total body (0.013±0.016 g/cm²) occurred in response to HRT, and these changes were significantly different from those in controls (spine, 0.005±0.020 g/cm²; neck, –0.007±0.026 g/cm²; trochanter, 0.002±0.014 g/cm²; Ward's triangle, 0.003±0.019 g/cm²; total body, –0.001±0.017 g/cm²). HRT appears to be most effective at weight-bearing sites that have a high cancellous bone content. This study demonstrates that HRT significantly increases bone mass of the lumbar spine and proximal femur in osteopenic, late postmenopausal women, and may, therefore, be effective in preventing osteoporotic fractures at these sites in this population.     

Effects of high-impact exercise on bone mineral density: a randomized controlled trial in premenopausal women

Introduction: The purpose of this randomized controlled study was to assess the effects of high-impact exercise on the bone mineral density (BMD) of premenopausal women at the population level. Materials and methods: The study population consisted of a random population-based sample of 120 women from a cohort of 5,161 women, aged 35 to 40 years. They were randomly assigned to either an exercise or control group. The exercise regimen consisted of supervised, progressive high-impact exercises three times per week and an additional home program for 12 months. BMD was measured on the lumbar spine (L1–L4), proximal femur, and distal forearm, by dual-energy X-ray absorptiometry at baseline and after 12 months. Calcaneal bone was measured using quantitative ultrasound. Results: Thirty-nine women (65%) in the exercise group and 41 women (68%) in the control group completed the study. The exercise group demonstrated significant change compared with the control group in femoral neck BMD (1.1% vs –0.4%; p=0.003), intertrochanteric BMD (0.8% vs –0.2%; p=0.029), and total femoral BMD (0.1% vs –0.3%; p=0.006). No exercise-induced effects were found in the total lumbar BMD or in the lumbar vertebrae L2–L4. Instead, L1 BMD (2.2% vs –0.4%; p=0.002) increased significantly more in the exercise group than in the control group. Calcaneal broadband ultrasound attenuation showed also a significant change in the exercise group compared with the control group (7.3% vs –0.6%; p=0.015). The changes were also significant within the exercise group, but not within the control group. There were no significant differences between or within the groups in the distal forearm. Conclusions: This study indicates that high-impact exercise is effective in improving bone mineral density in the lumbar spine and upper femur in premenopausal women, and the results of the study may be generalized at the population level. This type of training may be an efficient, safe, and inexpensive way to prevent osteoporosis later in life.     

Pattern of bone loss of the proximal femur: a radiologic, densitometric, and histomorphometric study

The pattern of bone loss in the proximal femur was studied in 141 cadaveric femora from 36 women and 39 men ranging from 27 to 89 years of age. Bone mineral density (BMD) of the femoral neck, greater trochanter, Ward's triangle, and tensile and compressive stress regions were measured by dual photon absorptiometry. Radiographs were graded by Singh's method. Histomorphometry of tensile and compressive trabecular areas was performed on ground midsection of the methylmethacrylate-embedded whole proximal femur. Although Singh index had some correlation with BMD of the femoral neck, the various BMD measurements showed that all regions lost bone to the same extent; in particular, no selective bone loss was found at low stress regions (tensile trabeculae or Ward's triangle). Histomorphometry revealed that most of the trabecular bone loss of the proximal femur is attributable to a decrease in thickness of individual trabeculae.     

骨密度结合股骨近端几何参数预测老年髋部骨折

目的研究老年人骨密度(Bone mineral density,BMD)值结合股骨近端几何参数是否能提高骨质疏松性髋部骨折危险性的预测。方法将85例绝经后妇女髋部骨折患者按骨折类型分组, 其中52例股骨颈骨折,33例转子间骨折。对照组100例老年女性。在骨盆片上测量股骨近端几何参数,在股骨颈、Ward’s三角和转子处测量BMD值,对结果进行统计学处理分析。结果骨折组的BMD值均低于对照组(P<0．01);股骨干皮质厚度与股骨颈BMD值有相关性(r=0．45,P< 0．01);逐步线性回归分析结果显示股骨距内侧皮质厚度、转子处BMD值、颈干角和Ward’s三角 BMD值相结合是预测髋部骨折最好方法(r=0．74,r2=0．53,P<0．01)。结论骨密度值结合放射学测量股骨近端几何参数能提高对骨质疏松性髋部骨折及骨折类型的预测。     

Monitoring skeletal response to treatment which site to measure in the femur?

In the past it was usual to interpret bone mineral density (BMD) scans of the femur using the femoral neck, trochanter, or Ward's triangle sites. Recently, a study by the International Committee for Standards in Bone Measurement recommended that the total hip should be the preferred site for the interpretation of femur BMD, and another study described a new central hip site that may offer improved precision. This article compares the longitudinal sensitivities of the different femur BMD sites for monitoring patient response to treatment. The study population was 152 postmenopausal women enrolled in a trial of a bisphosphonate therapy. Spine and hip BMD scans were performed at 0, 1, and 2 yr. The mean percentage change at 2 yr was calculated for six sites in the hip, and the spine was also included for comparison. Treatment effect was defined as the difference in the BMD change between the treated and placebo groups. Although the data analysis incorporated a term for a calibration change caused by a repair of the dual X-ray absorptiometry scanner, the effect of this event on the estimation of treatment effect was negligible. Longitudinal sensitivity was derived by dividing the treatment effect by the root mean square error (RMSE) of the statistical model. Results (and standard errors) normalized to the ratio of treatment effect: RMSE for femoral neck BMD were as follows: femoral neck: 1.00; trochanter: 1.33 (0.38); intertrochanteric: 0.84 (0.41); total hip: 1.20 (0.38); Ward's triangle: 1.03 (0.27); central hip: 1.09 (0.30); spine: 2.08 (0. 45). At none of the femur sites was the change in BMD large enough to allow monitoring of response to treatment in individual patients. However, for studies involving the follow-up of a group of subjects, the longitudinal sensitivities of the different femur sites were equal within the statistical errors of the study. In particular, total hip BMD appears to be as effective as femoral neck BMD for detecting response to treatment in the femur in the setting of a clinical trial or similar research study.