Bone Mineral Density and Vertebral Fractures in Men

In women, many studies indicate that the risk of vertebral fragility fractures increases as bone mineral density (BMD) declines. In contrast, few studies are available for BMD and vertebral fractures in men. It is uncertain that the strength of the relationship between BMD and fractures is similar in magnitude in middle-aged men and in postmenopausal women. In the present study, 200 men (mean age 54.7 years) with lumbar osteopenia (T-score <−1.5) were recruited to examine the relationships between spine BMD and hip BMD and the associations of BMD with vertebral fractures. Lumbar BMD was assessed from L2 to L4, in the anteroposterior view, using dual-energy X-ray densitometry. At the upper left femur, hip BMD was measured at five regions of interest: femoral neck, trochanter, intertrochanter, Ward’s triangle and total hip. Spinal radiographs were analyzed independently by two trained investigators and vertebral fracture was defined as a reduction of at least 20% in the anterior, middle or posterior vertebral height. Spinal radiographs evidenced at least one vertebral crush fracture in 119 patients (59.5%). The results of logistic regression showed that age, femoral and spine BMDs were significant predictors of the presence of a vertebral fracture. Odds ratios for a decrease of 1 standard deviation ranged from 1.8 (1.3–2.8) for spine BMD to 2.3 (1.5–3.6) for total hip BMD. For multiple fractures odds ratios ranged from 1.7 (1.1–2.5) for spine BMD to 2.6 (1.7–4.3) for total hip BMD. In all models, odds ratios were higher for hip BMD than for spine BMD, particularly in younger men, under 50 years. A T-score <−2.5 in the femur (total femoral site) was associated with a 2.7-fold increase in the risk of vertebral fracture while a T-score <−2.5 in the spine was associated with only a 2-fold increase in risk. This study confirms the strong association of age and BMD with vertebral fractures in middle-aged men, shows that the femoral area is the best site of BMD measurement and suggests that a low femoral BMD could be considered as an index of severity in young men with lumbar osteopenia. Received: 27 October 1998 / Accepted: 22 February 1999     

Proximal Femur Geometry To Detect and Distinguish Femoral Neck Fractures from Trochanteric Fractures in Postmenopausal Women

Some proximal femur geometry (PFG) parameters, measured by dual-energy X-ray absorptiometry (DXA), have been reported to discriminate subjects with hip fracture. Relatively few studies have tested their ability to discriminate femoral neck fractures from those of the trochanter. To this end we performed a cross-sectional study in a population of 547 menopausal women over 69 years of age with femoral neck fractures (n= 88), trochanteric fractures (n= 93) or controls (n= 366). Hip axis length (HAL), neck–shaft angle (NSA), femoral neck diameter (FND) and femoral shaft diameter (FSD) were measured by DXA, as well as the bone mineral density (BMD) of the nonfractured hip at the femoral neck, trochanter and Ward’s triangle. In fractured subjects, BMD was lower at each measurement site. HAL was longer and NSA wider in those with femoral neck fractures. With logistic regression the age-adjusted odds ratio (OR) for a 1 standard deviation (SD) decrease in BMD was significantly associated at each measurement site with femoral neck fracture (femoral neck BMD: OR 1.9, 95% confidence interval (95% CI): 1.4–2.5; trochanter BMD: OR 1.6, 95% CI 1.2–2.0; Ward’s triangle BMD: OR 1.7, 95% CI 1.3–2.2) and trochanteric fracture (femoral neck BMD: OR 2.6, 95% CI 1.9–3.6; trochanter BMD: OR 3.0, 95% CI 2.2–4.1; Ward’s triangle BMD: OR 1.8, 95% CI 1.4–2.3). Age-adjusted OR for 1 SD increases in NSA (OR 2.2, 95% CI 1.7–2.8) and HAL (OR 1.3, 95% CI 1.1–1.6) was significantly associated with the fracture risk only for femoral neck fracture. In the best predictive model the strongest predictors were site-matched BMD for both fracture types and NSA for neck fracture. Trochanteric BMD had the greatest area (0.78, standard error (SE) 0.02) under the receiver operating characteristic curve in trochanteric fractures, whereas for NSA (0.72, SE 0.03) this area was greatest in femoral neck fractures. These results confirm the association of BMD with proximal femur fracture and support the evidence that PFG plays a significant role only in neck fracture prediction, since NSA is the best predictive parameter among those tested. Received: 24 April 2001 / Accepted: 1 August 2001     

Bone Mass and Structure at the Hip in Men and Women over the Age of 60 Years

Bone mass and structure at the proximal femur are important predictors of hip fracture. The aims of this study were to compare in a large sample of elderly men and women the precision of measurements of bone mass and structure at multiple sites at the proximal femur, to examine their interrelationships, to establish their relationships with age and body size, and to examine criteria for defining geometric and architectural variables in bone structure. Women (n= 336) and men (n= 141) over the age of 60 years were studied cross-sectionally. Bone mineral density (BMD) and content (BMC) at the proximal femur were measured in duplicate by dual-energy X-ray absorptiometry (DXA). Shaft and total upper femur (hip) sites in addition to femoral neck, Ward's triangle and trochanter were measured. Structural variables, measured from radiographs and from DXA images, including cortical thickness at calcar femorale, lateral cortex and mid-femur, width of the femur and medulla, Singh grade, hip and femoral axis length, femoral head and neck width and the center of mass of the femoral neck. BMD and BMC had high reproducibility and there were significant differences in reproducibility across sites. Among sites, total upper femur and shaft had the highest reproducibility. Duplicate measurements substantially improved reliability of the measurement and are recommended when the value is close to a diagnostic level or when it will be used to establish rates of change. Reproducibility of structural variables was also high except for the lateral cortex, center of mass and Singh grade. Variance due to measurement error did not change with either age or gender. Women were significantly different from men, after controlling for differences in body size, in all variables except Singh grade and medulla width. BMD and BMC were negatively related to age and positively to body size. Structural variables examined in relation to age and body size fell into two categories. The first comprised variables that were not age-related but were body-size-related, suggesting that they could be classified as geometric variables. The second comprised variables that were both body-size-related and age-related, suggesting that they could be classified as architectural variables. Using these criteria, calcar and lateral cortex were architectural variables, whereas shaft width, hip and femoral axis length, femoral head and neck width, and center of mass were geometric in both men and women. In women, shaft cortex width and medulla width were age-related, whereas in men they were not. Singh grade showed no consistent pattern with age or body size in women and men. Received: 7 January 1997 / Accepted: 7 November 1997     

Hip Fracture Risk and Proximal Femur Geometry from DXA Scans

In this retrospective study of hip fracture risk evaluation from hip dual-energy X-ray absorptiometry (DXA) scans, our objectives were to determine which part of the femoral neck length contributes most to the fracture risk and to define a geometric parameter better than hip axis length (HAL) for discriminating hip fracture patients. Forty-nine Caucasian women with a nontraumatic femoral neck fracture were matched on age to 49 normal women and on both age and femoral neck bone mineral density (BMD) to 49 unfractured women. In addition to BMD, geometric parameters including neck–shaft angle, neck width and several HAL segments were evaluated by discriminant analysis to determine which was the best hip fracture discriminator. Neck–shaft angle had a limited influence on the hip fracture risk. Age-related bone loss was associated with a neck width increase in unfractured and fractured patients. HAL was significantly longer in fractured patients and was a significant discriminator between fractured patients and normal controls. HAL was not significant as a discriminator between fractured and low-BMD unfractured patients. The intertrochanter–head center distance (from the intertrochanteric line to the femoral head center) coincides with the femoral lever arm and includes no segments that adapt to BMD changes, such as the greater trochanter–intertrochanter distance. Among all tested lengths, this segment was the part of HAL that discriminated best between fractured and low-BMD unfractured patients. A longer intertrochanter–head center distance increased the risk of femoral neck fracture among low-BMD patients. Including automatic measurement of this segment in standard DXA protocols may prove useful in identifying patients at high risk for hip fracture. At present, HAL remains the easier neck length to measure, but automatic evaluation of the intertrochanter–head center distance must be a goal for future image analysis development. Received: 11 April 2001 / Accepted: 3 January 2002     

Femoral Neck and Intertrochanteric Fractures Have Different Risk Factors: A Prospective Study

The aim of this study was to determine whether both types of hip fracture, femoral neck and intertrochanteric, have similar risk factors. A prospective cohort study was carried out on community-dwelling elderly women in four areas of the United States: Baltimore, MD; Pittsburgh, PA; Minneapolis, MN and Portland, OR. The participants were 9704 Caucasian women, 65 years and older, of whom 279 had fractured their femoral neck and 222 had fractured their trochanteric region of the proximal femur. The predictors used were the bone mass of the calcaneus and proximal femur, anthropometry, history of fracture (family and personal), medication use, functional status, physical activity and visual function. The main outcome measures were femoral neck and intertrochanteric fractures occurring during an average of 8 years of follow-up. In multivariate proportional hazards models, several risk factors increased the risk of both types of hip fracture; including femoral neck bone density and increased functional difficulty. In hazard regression models that directly compared risk factors for the two types of hip fracture, calcaneal bone mineral density (BMD) predicted femoral neck fractures more strongly than intertrochanteric fractures (OR = 1.16; 95% CI = 1.02–1.31). Steroid use and impaired functional status also predicted femoral neck fractures instead of intertrochanteric fractures. Poor health status (OR = 0.74; 95% CI = 0.55–1.00) predicted intertrochanteric fractures more strongly than femoral neck fractures. We conclude that femoral neck fractures are largely predicted by BMD and poor functional ability while aging and poor health status predispose to intertrochanteric fractures. Received: 8 February 2000 / Accepted: 10 June 2000     

Proximal Femoral Dimension in Elderly Chinese Women with Hip Fractures in Taiwan

To investigate the relationship between proximal femoral geometry and the occurrence of hip fracture, we compared the geometry of contralateral normal hips of 120 elderly Chinese women with hip fractures, including 63 femoral neck fractures (group A) and 57 intertrochanteric fractures (group B) due to minor trauma, with that of 72 normal elderly Chinese women (group C). The mean ages for group A, B and C subjects were 77.3, 79.7 and 72.9 years, respectively. The femoral neck length (NL), neck width (NW), diameter of femoral head, femoral shaft width just below the lesser trochanter, and neck–shaft angle (θ) were measured on the anteroposterior plain pelvic radiographs. The mean ± SD of NL for group A was 50.4 ± 3.3 mm; for group B, 50.6 ± 3.1 mm; and for group C, 48.8 ± 3.6 mm. Statistical analysis by ANOCOVA and regression showed that only NL of women with hip fractures was significantly longer than controls after correction for age, body height and weight (p <0.01). However, the difference in NL between group A and group B was not significant. By linear regression, the probability of fracture increased only with older age (p <0.001), longer NL (p <0.005) and lighter body weight (p <0.05). By logistic regression, each standard deviation increase in NL increased the risk of hip fracture (age-adjusted odds ratio 1.84; 95% CI, 1.11–3.06). The results confirm the relationship between proximal femoral geometry and the occurrence of hip fracture in elderly Chinese women in Taiwan. Received: 7 August 1998 / Accepted: 6 January 1999     

Assessment of a New Quantitative Ultrasound Calcaneus Measurement: Precision and Discrimination of Hip Fractures in Elderly Women Compared with Dual X-ray Absorptiometry

The incidence of osteoporotic hip fracture increases in postmenopausal women with low hip bone mineral density (BMD). Dual X-ray absorptiometry (DXA) is the most commonly used technique for the assessment of bone status and provides good measurement precision. However, DXA affords little information about bone architecture. Quantitative ultrasound (QUS) systems have been developed to evaluate bone status for assessment of fracture risk. Our study was designed to assess a new QUS system from Hologic, the Sahara; to compare it with a previous model, the Walker-Sonix UBA 575+; and to investigate whether it is able to discriminate between women with and without fracture. Using both ultrasound devices, the measurements were performed at the heels of 33 postmenopausal women who had recently sustained hip fracture. A control group of 35 age-matched postmenopausal women was recruited for comparison. The total, neck and trochanter femoral BMD values were assessed using DXA for both groups. QUS and DXA measurements were significantly lower in fractured patients (p<0.005) than in the control group. The short-term, mid-term and standardized short-term precisions were used to evaluate the reproducibility of the two QUS systems. The Sahara showed a better standardized coefficient of variation for broadband ultrasound attenuation (BUA) than did the UBA 575+ (p<0.001). The correlation of BUA and speed of sound (SOS) between the two QUS devices was highly significant, with an r value of 0.92 for BUA and 0.91 for SOS. However, the correlation between DXA and ultrasound parameters ranged from 0.28 to 0.44. We found that ultrasound measurements at the heel were significant discriminators of hip fractures with odds ratios (OR) ranging from 2.7 to 3.2. Even after adjusting the logistic regressions for total, neck or trochanter femoral BMD, QUS variables were still significant independent discriminators of hip fracture. The areas under the ROC curves of each ultrasound parameter ranged from 0.75 to 0.78, and compared very well with femoral neck BMD (p>0.05). In conclusion, our study indicated that the calcaneal QUS variables, as measured by the Sahara system can discriminate hip fracture patients equally as well as hip DXA. Received: 29 October 1999 / Accepted: 7 September 1999     

Femoral Bone Mineral Density, Neck-Shaft Angle and Mean Femoral Neck Width as Predictors of Hip Fracture in Men and Women

The effect of femoral bone mineral density (BMD) and several parameters of femoral neck geometry (hip axis length, neck–shaft angle and mean femoral neck width) on hip fracture risk in a Spanish population was assessed in a cross-sectional study. All parameters were determined by dual-energy X-ray absorptiometry. There were 411 patients (116 men, 295 women; aged 60–90 years) with hip fractures in whom measurements were taken in the contralateral hip. Controls were 545 persons (235 men, 310 women; aged 60–90 years) who participated in a previous study on BMD in a healthy Spanish population. Femoral neck BMD was significantly lower, and neck–shaft angle and mean femoral neck width significantly higher, in fracture cases than in controls. The logistic regression analysis adjusted by age, height and weight showed that a decrease of 1 standard deviation (SD) in femoral neck BMD was associated with an odds ratio of hip fracture of 4.52 [95% confidence interval (CI) 2.93 to 6.96] in men and 4.45 (95% CI 3.11 to 6.36) in women; an increase of 1 SD in neck–shaft angle of 2.45 (95% CI 1.73 to 3.45) in men and 3.48 (95% CI 2.61 to 4.65) in women; and an increase of 1 SD in mean femoral neck width of 2.15 (95% CI 1.55 to 2.98) in men and 2.40 (95% CI 1.79 to 3.22) in women. The use of a combination of femoral BMD and geometric parameters of the femoral neck except for hip axis length may improve hip fracture risk prediction allowing a better therapeutic strategy for hip fracture prevention. Received: 16 September 1999 / Accepted: 22 February 2000     

Use of Clinical Risk Factors in Elderly Women with Low Bone Mineral Density to Identify Women at Higher Risk of Hip Fracture: The EPIDOS Prospective Study

Elderly women with very low bone mineral density (BMD) (T-score ≤−3.5) have a risk of hip fracture more than two times higher than the average risk of women of the same age. Using data from the EPIDOS prospective study, we have shown that by measuring BMD on the 50% of women who have the lowest weight, it is possible to identify the majority of these women at higher risk. In the present analysis, we assessed whether the use of clinical risk factors, in the subset of women selected for osteodensitometry and with moderately low BMD (T-score between −3.5 and −2.5), allows the identification of another subgroup of women with a risk 2 times higher than average and, thereby, increases the efficiency of selective BMD screening. We then assessed the discriminant value for hip fracture of the overall screening strategy (i.e., use of weight to select women for osteodensitometry, then use of clinical risk factors to enhance the predictive value of BMD), and compared it with the value of BMD used as a population screening tool. In total, 6933 EPIDOS participants, aged 75 years or above, were included in this analysis. Using Cox regression models, we first determined which baseline factors were most predictive of hip fracture among the 1588 women with weight below median (selection criteria for osteodensitometry in the proposed strategy) and T-score between −3.5 and −2.5. Based on the relative risk (RR) estimates from the final risk function, we calculated an individual risk score for hip fracture. We assessed the incidence of hip fracture for each value of the score, and determined the cutoff to identify women with a risk about 2 times higher than the average risk in this elderly cohort. The overall screening strategy (i.e., selective BMD measurement based on weight, followed by clinical fracture risk assessment) identifies two subgroups of higher risk women: a group with very low BMD (T-score ≤–3.5), and another group with moderately low BMD (T-score between –3.5 and –2.5) but a high fracture risk score. We calculated the total number of women classified as being at high risk, and assessed the overall sensitivity and specificity of this strategy to identify elderly women who will suffer a hip fracture. Among women with weight below median and T-score between −3.5 and −2.5, the factors most predictive of the risk of hip fracture were age, history of fall, ability to do the tandem walk (test of dynamic balance), gait speed and visual acuity. A simple additive score based on these factors (except visual acuity) allows a high-risk group (risk about 2 times higher than average) to be clearly distinguished from a low-risk group (risk below average). Overall, the proposed strategy identifies approximately 15% of the women in the cohort as being at high risk, i.e., 543 women with T-score ≤−3.5 and 503 women with −3.5 <T-score ≤−2.5 and a high fracture risk score. The sensitivity for hip fracture is equal to 37% and the specificity to 85%, which is equivalent to the discriminant value of BMD as a population screening tool. In elderly women, the use of a simple clinical risk score, in women with previous BMD values, allows the number of high-risk women identified to be increased. Overall, the proposed screening strategy (use of weight to select women for osteodensitometry, and then use of clinical risk factors to enhance the predictive value of BMD) has the same discriminant value for hip fracture as BMD used as a population screening tool. Received: 20 November 2001 / Accepted: 11 February 2002     

Inappropriate Reference Range for Peak Bone Mineral Density in Dual-energy X-ray Absorptiometry: Implications for the Interpretation of T-scores

An inappropriate reference range for peak bone mineral density (BMD) may result in identification of an incorrect proportion of subjects with osteopenia and osteoporosis at dual-energy X-ray absorptiometry (DXA). In this study, we assessed the prevalence of low BMD in Turkish young adults with respect to local population reference range T-scores and the US reference range T-scores. The BMD values of lumbar spine (L1–L4) and proximal femur (femoral neck, intertrochanter, trochanter, Ward”s triangle and total) were measured by DXA in 323 healthy young adults (171 women, 152 men) aged 19–25 years. The World Health Organization criteria for the diagnosis of osteopenia (−2.5 <T-score <−1) and osteoporosis (T-score ≤−2.5) were applied. In women, the means of the US reference range T-scores were significantly lower than zero at the spine and proximal femoral sites (p<0.0001). In men, the means of the US reference range T-scores were significantly lower than zero at the spine, femoral neck, intertrochanter, total femur (p<0.0001) and trochanter (p<0.05), but not at Ward”s triangle (p=0.92). When the diagnoses were based on local population reference range T-scores instead of the US reference range T-scores, the prevalence of low BMD (T-score <−1) in women fell from 50.3% to 14.0% at the lumbar spine and from 60.8% to 14.6% at the femoral neck, and in men from 42.8% to 15.8% at the lumbar spine and from 30.9% to 17.1% at the femoral neck. Our data suggest that individual populations should use their own reference range T-scores to avoid misdiagnoses of osteopenia and osteoporosis by DXA. Received: 4 November 1999 / Accepted: 29 March 2000     

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.     

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.     

The Effect of 17β-Estradiol at Doses of 0.5, 1 and 2 mg Compared with Placebo on Early Postmenopausal Bone Loss in Hysterectomized Women

In a randomized double-masked placebo-controlled parallel-group trial 166 hysterectomized (± oophorectomy) perimenopausal and postmenopausal women aged 45–55 years with a follicle stimulating hormone level above 20 IU/l were treated with one daily dose of either 0.5 mg 17β-estradiol (E₂), 1 mg E₂, 2 mg E₂ or placebo for 2 years. Bone mineral density (BMD) and biochemical bone markers were determined. All three doses of E₂ were significantly better than placebo with respect to change in BMD at the lumbar spine (L1–L4) (p<0.0001 for all pairwise comparisons) and hip (femoral neck, trochanter, Ward’s triangle). The mean percentage change from baseline at the lumbar spine was −0.2%, 0.8% and 1.8% in the 0.5, 1 and 2 mg E₂ groups respectively compared with −3.5% in the placebo group. Both 1 and 2 mg E₂ were significantly better than placebo in increasing the BMD at the femoral neck (p<0.001), trochanter (p<0.01) and Ward’s triangle (p<0.0001), while 0.5 mg E₂ was significantly better than placebo at the femoral neck (p<0.001) and Ward’s triangle (p<0.0001). The overall difference in mean percentage change in BMD at the femoral neck versus placebo (−0.2%) was 3.8% for 0.5 mg, 4.0% for 1 mg and 3.9% for 2 mg E₂; the corresponding numbers for trochanter were −0.3%, 1.3%, 3.3% and 3.2%, respectively, and −2.2%, 2.9%, 2.9% and 4.0%, respectively, for Ward’s triangle. More than half the women who received placebo presented with a decrease in BMD at the hip. The percentage of women in the 0.5 mg E₂ group who maintained or increased BMD at the femoral neck, trochanter and Ward’s triangle was 69%, 56% and 44%, respectively. For 1 mg E₂ the numbers were 69%, 78% and 61% respectively, and for 2 mg E₂ were 59%, 68% and 59% respectively. Osteocalcin, serum pyridinium crosslinks, urinary pyridinium crosslinks and urinary hydroxyproline/creatinine decreased significantly (p<0.0001, p<0.05) in the 0.5, 1 and 2 mg E₂ groups compared with the placebo group after 6 and 24 months of treatment. Received: 28 May 2001 / Accepted: 11 October 2001     

Bone Mineral Density Differences at the Femoral Neck and Ward's Triangle: A Comparison Study on the Reference Data Between Chinese and Caucasian Women

The incidence of hip fracture is lower in Chinese women compared with those from western countries, though they usually have lower bone mineral density (BMD). In this study, reference data (from Caucasian women) supplied by the manufacturer of Hologic Inc. was compared with data obtained from healthy women in Changsha, Hunan province, P.R.C. A total of 1488 Chinese women aged 15–95 years were randomly chosen for the study. Measurements of BMD were taken at the hip by dual energy X-ray absorptiometry (DXA) (QDR 4500A, Hologic Inc., USA). The BMD and the BMD decrease rate were somewhat lower than reference curves at all age groups and all sites except for the femoral neck and Ward's triangle. Chinese women reached their peak BMD 5–10 years later than their counterparts, and had a lower BMD decrease rate for about 35 years after peak BMD was attained. The fact that Chinese women take longer time to reach peak BMD and have a lower BMD decrease rate at the neck and Ward's triangle after peak BMD is attained protects them against hip fractures, and is a phenomenon that needs to be studied in the future. Received: 11 May 1999 / Accepted: 29 February 2000     

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.     

Digital X-ray Radiogrammetry Predicts Hip,Wrist and Vertebral Fracture Risk in Elderly Women: A Prospective Analysis from the Study of Osteoporotic Fractures

Digital X-ray radiogrammetry (DXR) is a technique that uses automated image analysis of standard hand radiographs to estimate bone mineral density (DXR-BMD). Previous studies have shown that DXR-BMD measurements have high precision, are strongly correlated with forearm BMD and are lower in individuals with prevalent fractures. To determine whether DXR-BMD measurements predict wrist, hip and vertebral fracture risk we conducted a case–cohort study within a prospective study of 9704 community-dwelling elderly women (the Study of Osteoporotic Fractures). We compared DXR-BMD, and BMD of the radius (proximal and distal), calcaneus, femoral neck and posteroanterior lumbar spine in women who subsequently suffered a wrist (n= 192), hip (n= 195), or vertebral fracture (n= 193) with randomly selected controls from the same cohort (n= 392–398). DXR-BMD was estimated from hand radiographs acquired at the baseline visit. The radiographs were digitized and the Pronosco X-posure System was used to compute DXR-BMD from the second through fourth metacarpals. Wrist fractures were confirmed by radiographic reports and hip fractures were confirmed by radiographs. Vertebral fractures were defined using morphometric analysis of lateral spine radiographs acquired at baseline and an average of 3.7 years later. Age-adjusted odds ratio (OR, vertebral fracture) or relative hazard (RH, wrist and hip fracture) for a 1 SD decrease in BMD were computed. All BMD measurements were similar for prediction of wrist (RH = 1.5–2.1) and vertebral fracture (OR = 1.8–2.5). Femoral neck BMD best predicted hip fracture (RH = 3.0), while the relative hazards for all other BMD measurements were similar (RH = 1.5–1.9). These prospective data indicate that DXR-BMD performs as well as other peripheral BMD measurements for prediction of wrist, hip and vertebral fractures. Therefore, DXR-BMD may be useful for prediction of fracture risk in clinical settings where hip BMD is not available. Received: 27 April 2001 / Accepted: 10 October 2001     

Ten Year Probabilities of Osteoporotic Fractures According to BMD and Diagnostic Thresholds

The objectives of the present study were to estimate 10 year probabilities of osteoporotic fractures in men and women according to age and bone mineral density (BMD) at the femoral neck. Risks were computed from the incidence of a first hip, distal forearm, proximal humerus and symptomatic vertebral fracture from patient records in Malmo¨, Sweden and future mortality rates for each year of age from Poisson models using the Swedish patient register and statistical year book. Fracture probability was computed using the Swedish population and cut-off values for T-scores based on the NHANES III female population. We assumed that the risk of fracture increased with decreasing BMD as assessed by meta-analysis in independent studies. The 10-year probability of any fracture was determined from the proportion of individuals fracture-free from the age of 45 years. With the exception of forearm fractures in men, 10 year probabilities increased with age and T-score. In the case of hip and spine fractures, fracture probabilities for any age with low BMD were similar between men and women. The effect of age on risk independently of BMD suggests that intervention thresholds should not be at a fixed T-score but vary according to absolute probabilities. Intervention thresholds based on hip BMD T-scores are similar between sexes. Received: 14 December 2000 / Accepted: 2 July 2001     

Bone mineral density in chinese elderly women with hip fracture

In order to examine the status of osteoporosis of the patients with hip fracture, we assessed the bone mineral density (BMD) of the contralateral hip of 81 elderly females with hip fracture and compared those with 77 normal Chinese women. The age of fracture subjects was 73.5±6.6 years (mean±SD), and 69.2±6.9 years for the controls. All of these fractures were caused by minor trauma, such as falls from a standing position or slipping to the ground. The Norland 2600 dual-photon absorptiometer (DPA) was used to evaluated the BMD in the femoral neck, trochanter, and Ward's triangle areas. The BMD for the fracture subjects was significantly lower than those of the controls. By linear regression, the probability of fracture increased exponentially with age and low BMD. The mean BMD for femoral neck of the fracture subjects versus controls was 0.556 versus 0.624 g/cm²; for trochanter: 0.505 versus 0.566 g/cm²; for Ward's triangle: 0.432 versus 0.485 g/cm². Both negative predictive value (NPV) and positive predictive value (PPV) were acceptable at the prevalence of hip fracture of 5% or 20% and at a cutoff point of 0.65 g/cm². These data revealed that the degree of relative osteoporosis in the patients with hip fractures was more severe than that of controls.     

DXA of the Hip and Heel Ultrasound but not Densitometry of the Fingers Can Discriminate Female Hip Fracture Patients from Controls: A Comparison Between Four Different Methods

Dual-energy X-ray absorptiometry (DXA) of the proximal femur and in more recent years quantitative ultrasound (QUS) of the heel are the most established methods for assessing hip fracture risk. Measurement of the fingers offers a new approach. We performed DXA of the proximal femur, QUS of the heel and fingers, and radiographic absorptiometry (RA) of the fingers in 87 non-institutionalized women, 65–85 years of age, with a first hip fracture and compared them with 195 randomly selected age-matched controls. Bone mineral density (BMD) of the femoral neck and heel Stiffness Index were significantly lower among cases than among controls (by 15% and 17%, respectively; p<0.0001), whereas no significant differences were found for finger measurements. When applying the WHO criterion of osteoporosis, 62–98% of the patients were classified as osteoporotic, compared with 19–85% of the controls, depending on method and site. The risks of hip fracture, estimated as odds ratios for every 1 SD reduction in femoral neck BMD, heel Stiffness Index, finger QUS and finger RA, were: 3.6 (95% CI 2.4–5.5), 3.4 (95% CI 2.2–5.0), 1.0 (95% CI 0.7–1.3) and 1.2 (95% CI 0.8–1.6), respectively. Compared with women with normal BMD of the femoral neck, those classified as osteopenic had an odds ratio of hip fracture of 14 (95% CI 2-110), whereas those classified as osteoporotic had an odds ratio of 63 (95% CI 8–501). We conclude that hip DXA and heel QUS have similar capacities to discriminate the risk of a first hip fracture, whereas QUS and RA of the phalanges seem inferior techniques for differentiating female hip fracture patients from controls. Received: 10 March 2000 / Accepted: 21 September 2000     

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。