Ultrasound Velocity and Cortical Bone Characteristics In Vivo

Axial transmission of ultrasound along cortical bone may reflect a combination of material and structural properties of long bone cortices. The goal of this study was to determine the association of speed of sound (SOS) with cortical density (CoD), cortical wall thickness (CWT), and total cortical area (CoA). Quantitative ultrasound (QUS) and peripheral quantitative computed tomography (pQCT) were used to measure the above variables in the distal third of radius and the midshaft of tibia in 51 postmenopausal women aged 62 to 71 years. Univariate regression analysis showed that the site-specific CoD accounted for 34% of the variability in the radial SOS and 29% of that in the tibial SOS (p<0.001 both). SOS was only moderately associated with radial CWT (R²= 0.14, p<0.05) and CoA (R²= 0.12, p<0.05), but not with tibial CWT nor CoA. After controlling for CoD, these dimension-related associations disappeared. Stepwise multiple regression analysis showed that CoD was the only significant determinant of radial SOS (adjusted R²= 0.31), whereas for tibia, not only CoD but also the years since menopause were associated with SOS (adjusted R²= 0.41). In conclusion, out of the studied macroscopic cortical variables, CoD (an apparent surrogate for material properties of bone) was the only determinant of SOS measured in vivo at radial and tibial shafts. The key question that still needs to be answered is whether the SOS information obtained from the peripheral long bone cortical shafts can be translated to describe the mechanical competence and quality of clinically pertinent bones (e.g. proximal femur) of a given individual. Received: 23 March 2000 / Accepted: 18 December 2000     

Dual photon absorptiometry of the proximal tibia

Summary Bone mineral content (BMC) and bone mineral density (BMD) of the proximal tibia were determined by dual photon absorptiometry on 44 women, aged 23–87 years. The area of the tibia measured was a 2.01 cm region immediately distal to the medial and lateral tuberosities. Values of BMC ranged between 5.09 and 14.57 g and BMD between 0.380 and 1.180 g/cm². Both tibial BMC and BMD declined with age and tibial BMD was significantly correlated with lumbar spine (r=0.70), femoral neck (r=0.73), and femoral trochanter (r=0.74). However, the large standard errors of estimate (SEE) (0.08–0.14 g/cm²) do not allow for reliable prediction in an individual of other skeletal sites by the tibia. Repeated measurements demonstrated that dual photon absorptiometry of the proximal tibia is a reliable measurement and may be a useful tool in the monitoring of therapeutic or intervention modalities in those individuals with skeletal diseases in whom measurement of the lumbar spine or proximal femur may not be possible.     

Associations of hormone replacement therapy with bone structure and physical performance among postmenopausal women

The purpose of this cohort study was to focus on factors associated with bone mass and structure of lower limbs and physical performance after menopause. Eighty nonsmoking women with a mean age of 62.1 (SD 0.8) years participated in the study. They were classified into two groups by their use of hormone replacement therapy (HRT), either the current users (n = 43) or the never or discontinued users (n = 37). The tibial shaft and distal tibia were scanned with peripheral computed tomography. For the shaft region, the bone mineral content (BMC, g), cortical density (CoD, g/cm(3)), cortical area (CoA, mm(2)), and section modulus (BSI, mm(3)) were determined. For the distal part, the evaluated variables were BMC, total area (ToA), ratio of cortical to total area (CoA/ToA), trabecular density (TrD, g/mm(3)), cortical thickness, BSI, and buckling ratio. Isometric and dynamic muscle strength of the leg extensors, agility and postural sway, and cardiorespiratory capacity (VO(2max)) were measured. Unadjusted values for all bone variables were slightly higher among the HRT users compared to nonusers, with the exception of TrD with no difference. After controlling for body weight, the mean differences (95% confidence interval) remained significant for CoD of the tibial shaft and BSI of the distal tibia, the mean between-group differences being 1.5% (0.4 to 2.5%) and 23.0% (7.1 to 41.3%), respectively. Underlying the greater bending strength, HRT users had thicker cortices and a greater ratio of CoA/ToA. No differences existed between the two study groups for lower limb isometric or dynamic power, cardiorespiratory capacity, or postural balance or sway. HRT may offer protection against bone loss and maintain bone strength, although its ability to improve physical performance is not evident.     

Associations of calcium intake and physical activity with bone density and size in premenopausal and postmenopausal women: a peripheral quantitative computed tomography study.

The purpose of this cross-sectional study was to examine the impact of long-term physical activity (PA) and calcium intake on non-weight-bearing radius and weight-bearing tibia. Altogether, 218 healthy, nonsmoking women, [92 premenopausal women, mean age, 32.6 years (SD, 2.2 years), and 126 postmenopausal women, mean age, 67.3 years (SD, 2.0 years)] participated. The subjects were divided according to their habitual levels of physical activity (PA+ or PA-) and calcium intake (Ca+ or Ca-). The distal end and shaft regions of the radius and tibia were evaluated with peripheral quantitative tomography (pQCT). For the shaft regions, bone mineral content (BMC), cortical cross-sectional area (CoA), cortical density (CoD), and bone strength index, that is, 1-11.9% of the density-weighted section modulus (BSI) were determined. For the distal ends, BMC, total cross-sectional area (ToA), trabecular density (TrD), and BSI were determined. The BMC at the distal radius in the young PA+ group was 6.6% (95% CI, 1- to 11.9%) lower than that of the PA- group. A similar nonsignificant trend was found for the radial shaft. The radial shaft showed a mechanically more competent structure among the older subjects with a BSI 8.5% (95% CI, 1.8-15.6%) higher in the older PA+ group than in the older PA- group. The associations between calcium intake and the radial bone characteristics were systematically positive in both age groups. PA seemed to benefit the distal tibia. In the younger age group the TrD was 6.9% (95% CI, 1.8-12.4%) higher in the PA+ group, and in the elderly the BMC was 5% (95% CI, 0.3-9.9%) higher in the PA+ group than in the PA- group. Note that in the younger age group the ToA was 5.1% (95% CI, 0-9.1%) smaller in the PA+ group than in the PA- group, and in the older age group the ToA was 4.2% (95% CI, -0.3-8.9%) greater in the PA+ group than in the PA- group. The association of PA and bone characteristics at the tibial shaft was positive in both age groups (statistically significant for the older subjects). The tibial shaft BSI of the older PA+ group was 8.6% (95% CI, 2.6-14.9%) better than that of the old PA- group. There was no association between calcium intake and the tibial bone characteristics in either age group. In conclusion, high calcium intake was positively associated with a mechanically competent structure in the radius among both younger and older women, whereas the influence of PA did not become apparent until older ages. PA seemed to benefit particularly the weight-bearing tibia, whereas calcium intake was not associated with the tibia.     

Estimation of the Architectural Properties of Cortical Bone Using Peripheral Quantitative Computed Tomography

We assessed the volumetric bone mineral density (vBMD) and cross-sectional architecture of cortical bone at the distal radius by peripheral quantitative computed tomography (pQCT). The volumetric bone mineral density [integral bone mineral density (BMDi), trabecular bone mineral density (BMDt) and cortical with subcortical bone mineral density (BMDsc)] and the architectural parameters [cortical bone area (CBA), cortical thickness (C-th), moment of inertia (Im) and polar moment of inertia (Ip)] were measured in 115 healthy premenopausal women, 48 osteoporotic postmenopausal women and 78 age-matched healthy postmenopausal women. Age-matched healthy women had higher values of vBMD and architectural parameters at the distal radius than osteoporotic women. Premenopausal women had higher values of vBMD and architectural parameters at the distal radius than postmenopausal women. The differences in the architectural parameters between age-matched healthy women and osteoporotic women were more pronounced when only the high density area (threshold 0.70 cm^–1) was included. However, the differences in architectural parameters between premenopausal women and postmenopausal women were significant using even the lowest threshold value of 0.50 cm^–1 in the calculation. Receiver operating characteristic (ROC) curves were constructed and the areas under the curves calculated to evaluate the discriminating power of vBMD and architectural parameters. Comparison of the different ROC curves showed no statistical significance. In conclusion, our results suggest that both the density and mass distribution of the radius were clearly different between the healthy women and osteoporotic women. The differences in architectural parameters were more useful for studying the pathopysiology of osteoporosis than for contributing to the diagnosis. Determination of the cross-sectional mass distribution of bone combined with BMD should offer more information than BMD alone in the study of the pathophysiology of osteoporosis. Received: 22 December 1998 / Accepted: 2 June 1999     

Associations of vitamin C, calcium and protein with bone mass in postmenopausal Mexican American women

We investigated the associations of vitamin C, calcium and protein intakes with bone mass at the femoral neck and lumbar spine in postmenopausal Mexican American women. Bone mass was measured by dual-energy X-ray absorptiometry (DXA) and expressed as areal (BMD, g/cm²) and volumetric (bone mineral apparent density or BMAD, g/cm³) bone mineral density. Diet was assessed using a modified version of the National Cancer Institute Food Questionnaire, which was administered by trained bilingual interviewers familiar with Mexican dietary practices. Data gathered from 125 subjects were analyzed using multiple linear regression analysis with age, body mass index (BMI), acculturation, years of estrogen use, physical activity, total energy intake, and the nutrient of interest as independent variables. Neither calcium nor calcium/protein ratio was associated with bone mineral density. There was evidence of a positive association between dietary vitamin C intake and femoral neck BMD (β=0.0002 g/cm² per mg/day, SE=0.0001,p=0.07) and BMAD (β=0.0001 g/cm³ per mg/day, SE=0.00006,p<0.05), but vitamin C was not associated with lumbar spine bone mass. Further investigation of the role of vitamin C in skeletal health is warranted.     

Site Specificity of Bone Architecture Between the Distal Radius and Distal Tibia in Children and Adolescents: An HR-pQCT Study

High-resolution quantitative computerized tomography permits evaluation of site specific differences in bone architecture. The purpose of this study was to compare bone architecture between distal radius and distal tibia. We present bone architecture at the distal radius and distal tibia in 151 male and 172 female participants, as follows: total bone area (mm²), total bone density (mg HA/cm³), trabecular bone density (mg HA/cm³), cortical bone density (mg HA/cm³), cortical thickness (μm), trabecular number (1/mm), trabecular thickness (μm), and trabecular separation (μm). We evaluated differences in and correlations between bone variables (absolute values) across sites. We calculated individual z scores and used regression to assess discordance between sites. In pubertal and postpubertal male and female participants, absolute values of total bone area, cortical bone density, cortical thickness, and trabecular thickness were significantly lower at the radius compared with the tibia (P < 0.01). Absolute values for trabecular bone density were significantly lower at the radius compared with the tibia in postpubertal male and female participants (P < 0.01). Absolute values for trabecular separation was significantly lower at the radius compared with the tibia in pubertal female participants (P < 0.01). Bone architecture was moderately to highly correlated between sites (r = 0.34–0.85). There was discordance between z scores at the radius and tibia within male participants (pubertal R ² between 36 and 64%; postpubertal R ² between 22 and 77%) and female participants (pubertal R ² between 10 and 44%; postpubertal R ² between 25 and 62%). In conclusion, it is vital to evaluate bone architecture at the specific skeletal site of interest.     

Multisite Quantitative Ultrasound: Colles’ Fracture Discrimination in Postmenopausal Women

Distal forearm fractures are the most common perimenopausal fracture and are generally associated with osteoporosis. The aim of this study was to evaluate the capability of speed of sound (SOS) measurements in cortical bone at the phalanx, radius, tibia and metatarsal to discriminate Colles’ fracture cases from controls in postmenopausal women and to compare this with bone mineral density (BMD) measurements obtained by dual-energy X-ray absorptiometry (DXA). Sixty-three postmenpausal Colles’ fracture cases and 191 postmenopausal controls had SOS measurements of the radius, tibia, phalanx and metatarsal using a semi-reflection ultrasound technique and BMD measurements of the lumbar spine and proximal femur using DXA. The age-adjusted odds ratios (ORs) for fracture for the SOS measurement sites were 1.50 [95% CI 1.07–2.10] for the radius, 1.23 [0.86-1.76] for the tibia, 1.85 [1.06–3.23] for the phalanx and 1.74 [1.12–2.71] for the metatarsal site. For the BMD measurements the ORs were 1.95 [1.34–2.85] for the lumbar spine, 2.21 [1.43–3.40] for the femoral neck and 2.62 [1.69–4.08] for the total hip. The benefits of combining sites either by taking their average Z-score or by using the manufacturer’s ORI algorithm were evaluated. The two methods yielded similar results and the ORs for the combination of the radius and phalanx were 2.00 [1.21–3.33], for the radius and metatarsal 1.67 [1.05–2.67], for the phalanx and metatarsal 1.86 [1.11–3.08] and for the radius, phalanx and metatarsal 1.81 [1.07–3.06]. Combinations of DXA sites gave 2.22 [1.44–3.41] for the lumbar spine and femoral neck and 2.41 [1.57–3.70] for the lumbar spine and total hip. In conclusion, semi-reflection ultrasound measurements at the radius, phalanx or metatarsal demonstrated an ability to discriminate fracture cases from controls in postmenopausal Colles’ fracture patients, although the odds ratios were lower than with spine and femur BMD. Received: 6 July 2001 / Accepted: 11 December 2001     

Forearm bone mineral density in patients with rheumatoid arthritis

 The aims of the present study were to determine whether patients with rheumatoid arthritis (RA) show significantly lower forearm bone mineral density (BMD) than sex- and age-matched healthy controls, and to identify significant factors that are associated with their BMD loss. One hundred eighty-four patients with RA and 185 sex- and age-matched healthy controls were enrolled in the study: 71 men 37–68 years of age (RA, 31; controls, 40), 129 premenopausal women 30–48 years of age (RA, 67; controls, 62), and 169 postmenopausal women 48–69 years of age (RA, 86; controls, 83). The correlation of forearm BMD, measured by dual energy X-ray absorptiometry with anatomic grade in the wrist, functional class, duration of disease, steroid use, modified health assessment questionnaire (HAQ) score for the upper and lower extremities, levels of serum C-reactive protein and rheumatoid factor, erythrocyte sedimentation rate, and years since menopause (YSM) were examined by multiple regression analysis. In men with RA, no clinical factors were significantly correlated with forearm BMD, and the BMD did not differ significantly from that in controls (0.329 ± 0.060 [mean ± SD] vs. 0.351 ± 0.069 g/cm²). In premenopausal women with RA, the HAQ score for the upper extremities was positively correlated with forearm BMD (P < 0.05), but the BMD did not differ significantly from that in controls (0.298 ± 0.085 vs. 0.324 ± 0.088 g/cm²); in postmenopausal women with RA, YSM and anatomic grade in the wrist were negatively correlated with forearm BMD (P < 0.01 and P < 0.05), and the BMD was significantly lower than in controls (0.192 ± 0.063 vs. 0.223 ± 0.076 g/cm², P < 0.01). These findings suggest that forearm BMD loss in patients with RA may be accelerated in women after menopause, and that YSM and disuse of the wrist may be significant determinants of their forearm BMD loss. Received: February 18, 2002/ Accepted: May 23, 2002     

Use of Phalangeal Bone Mineral Density and Multi-site Speed of Sound Conduction to Monitor Therapy with Alendronate in Postmenopausal Women

In women with postmenopausal osteoporosis (PMO), response to therapy with bisphosphonates is conventionally monitored using central-site (hip and spine) bone mineral density (BMD), but more convenient alternatives are desirable. During a randomized parallel-group study of the efficacy of once-weekly (80 mg vs 160 mg) oral alendronate in the treatment of PMO, 81 women (mean age 70.2 years ± 4.6 SD) had BMD measurements of total hip (TH) and lumbar spine (LS) (L1–L4, Hologic); and of the middle phalanx of the middle digit of the non-dominant hand (accuDXA) at baseline and after 6 and 12 months of therapy with alendronate. At the same timepoints, subjects also had measurements of speed of sound (SOS) through bone at four sites (distal 1/3 radius, proximal phalanx of the third finger, midshaft of the tibia and fifth metatarsal) using the Sunlight Omnisense Ultrasound Bone Sonometer. Data from both patient groups were pooled for this analysis. Mean TH BMD at baseline was 0.705 g/cm²± 0.093 (SD) and increased by 1.7%± 2.3% and 2.5%± 2.3% at 6 and 12 months respectively (p= 0.09 and p<0.0001). Mean LS BMD at baseline was 0.718 ± 0.076 g/cm² and increased by 3.9%± 3.6% and 6.1%± 3.5 % at 6 and 12 months respectively (both p<0.0001). There was no statistically significant change from baseline in mean BMD by accuDXA at either 6 or 12 months. The only statistically significant changes in SOS were at the radius (decrease in SOS at 12 months, p = 0.04) and tibia (increase at 6 months, p<0.01, but no change between baseline and 12 months). Baseline correlation coefficients between accuDXA and LS and TH DXA were 0.22 (p= 0.05) and 0.27 (p= 0.02) respectively. Correlation coefficients between SOS and LS DXA ranged from 0.05 to 0.22; and between SOS and TH DXA ranged from –0.08 to 0.10 (all p= NS). These data suggest that the response to alendronate therapy over this time period cannot be measured by accuDXA or Sunlight SOS at the sites studied. Received: 26 June 2001 / Accepted: 27 September 2001     

Bone Density and Body Composition in Japanese Women

Total body bone mineral content (BMC_TB in g) and density (BMD_TB in g/cm²) and body composition were measured in 1006 healthy Japanese women aged 20–79 years using dual X-ray absorptiometry. Peak BMD_TB was 1.11 ± 0.05 g/cm² in women 20–49 years, and mean BMD_TB was 1.019 g/cm² in the 6th decade, 0.956 g/cm² in the 7th decade, and 0.900 g/cm² in the 8th decade. BMD_TB declined by 0.007 g/cm²/year in women after age 50. This age-related decline in BMD showed a similar pattern to that seen for the lumbar spine and femoral neck, but the actual rate of loss was lower for BMD_TB than for these other measurement sites. There was no significant difference between a eumenorrheic premenopausal group and a group with irregular menses. BMC_TB and BMD_TB were associated with body build, lean tissue mass, and fat mass (r = 0.29 ∼ 0.65 and 0.26 ∼ 0.41, respectively). Bone mass and density decreased significantly in older women of all body builds. Premenopausal Japanese women had a 5% lower BMD_TB than U.S. and European whites, but the difference was several times greater in postmenopausal than in premenopausal women. Received: 1 June 1995 / Accepted: 3 March 1997     

Comparison of effects of estriol on bone mineral density of vertebrae between elderly and postmenopausal women

To compare the efficacy of estriol (E₃) for postmenopausal and senile osteoporosis, we administered orally 1 g/day calcium lactate alone (control groups) or with 2 mg/day estriol (E₃ groups) to 20 postmenopausal women aged 50–65 years and 29 elderly women aged 70–84 years, and determined their bone mineral density (BMD) of the lumbar vertebrae AP scan by dual-energy X-ray absorptiometory. Of 41 subjects who completed 10 months of treatment, 8 postmenopausal women and 12 elderly women in the E₃ groups showed a significant (P < .05) increase in BMD, 5.59% ± 4.79% and 3.83% ± 7.90% of the respective basal values, while 10 postmenopausal women and 11 elderly women in the control groups showed a decrease in BMD, −4.02% ± 7.00% and −3.26% ± 4.60% of the respective basal values, after 10 months. On the other hand, genital bleeding as a side effect of E₃ occurred in 6 elderly subjects at this dose. Moreover, decrease in serum level of corrected calcium was seen only in the elderly women receiving E₃. Although a lower dosage of E₃ may be recommended for elderly subjects, these observations suggest, first, that hormone replacement therapy with E₃ has efficacy for involutional osteoporosis, and, second, that the bones in elderly women also maintain responsiveness to E₃. Received: May 19, 1997 / Accepted: July 7, 1997     

Ultrasound velocity of the tibia in normal german women and hip fracture patients

One of the latest developments in quantitative ultrasound (QUS) is the measurement of the speed of sound (SOS) of cortical bone of the midtibia. To determine the diagnostic validity of this method we measured 150 healthy women aged 22–94 years. Additionally, we report on first results of patients with hip fracture. Precisionin vivo of the tibial QUS expressed as the percentage coefficient of variation (CV) was 0.39% for the first day and 0.45% after repositioning the second day (mean CV=0.42%). No significant dependency of tibial SOS was found with weight, height, and body mass index in pre- and postmenopausal women. There was a significant decline of SOS with age in postmenopausal women (SOS=4225–5.3 age, r=−0.46,P<0.001), whereas premenopausal women showed no decline (SOS=3906+1.3 age, r=0.13, ns) Mean SOS values of premenopausal women were significantly higher than those of postmenopausal women (3960±78.7 m/second and 3898±120 m/second, respectively,P<0.001). Postmenopausal women on estrogen substitution had significantly higher mean tibial SOS values than age-comparable postmenopausal women without estrogen substitution (3980±99 m/second and 3869±100 m/second, respectively,P<0.001). Significant difference between age-matched healthy women, n=11, and hip fracture patients, n=13, expressed as z-score of −1.4 SD was found. In conclusion, tibial QUS declines with age and detects higher values in premenopausal women and postmenopausal women on estrogen substitution and lower values in hip fracture patients. Further prospective studies are needed to clarify its role in fracture risk assessment.     

An assessment of the use of quantitative ultrasound and the Osteoporosis Self-Assessment Tool for Asians in determining the risk of nonvertebral fracture in postmenopausal Chinese women

This cross-sectional study aims to assess the effectiveness of a simple, noninvasive scoring system, the Osteoporosis Self-Assessment Tool for Asians (OSTA), and quantitative bone ultrasound (QUS) in assessing nonvertebral fracture risk in Chinese postmenopausal women. A group of 513 community-dwelling women including 271 postmenopausal individuals participated in this study. Speed of sound (SOS m/s) at the radius, phalanx, and tibia were assessed by using the Omnisense prototype (Sunlight Ltd., Israel). Body height and weight were measured, and body mass index (BMI) and OSTA indices were calculated. Self-reported fractures were identified using a structured questionnaire. Phalanx SOS was significantly lower among postmenopausal women with a history of nonvertebral fracture occurred after menopause than those without (3755 m/s vs. 3841 m/s, P = 0.017, adjusted for age and weight), with an AUC of 0.66. The AUC of the OSTA for predicting nonvertebral fracture occurred after menopause was 0.64. SOS at the radius, phalanx, and tibia showed a positive correlation with OSTA index (r = 0.376–0.401, P < 0.001). The prevalence of nonvertebral fractures also increased significantly with the decreasing order of OSTA index (χ² = 5.432, P = 0.02). The OSTA values of ≤−1 and phalanx QUS T-score of ≤−1.95 can differentiate postmenopausal nonvertebral fracture with sensitivity of 75% and 81%, respectively, and specificity of 48% and 40%, respectively. Combining OSTA and phalanx QUS yielded a sensitivity of 83% and a specificity of 84% to detect postmenopausal nonvertebral fracture, with an AUC of 0.64. We conclude that OSTA and phalanx QUS are simple and effective clinical tools for identifying postmenopausal women at increased risk of nonvertebral fractures and can thereby facilitate the appropriate and more cost-effective use of bone densitometry to prevent osteoporotic fractures in developing countries.     

Spinal Trabecular Bone Loss and Fracture in American and Japanese Women

This study examined trabecular bone mineral density (BMD) in Japanese women with and without spinal fracture, and compared the results to American women with and without fracture. The quantitative computed tomography (QCT) systems used at the University of California, San Francisco (UCSF) and at Nagasaki University were cross-calibrated. Normative BMD was assessed with the K₂HPO₄ liquid phantom in 538 Americans aged 20–85 years, and with the B-MAS200 phantom in 577 Japanese aged 20–83 years. These BMD were adjusted for use with the Image Analysis solid phantom using the result of cross-calibration. The trabecular BMD in 111 postmenopausal American women (55 with fracture), and in 185 postmenopausal Japanese women (67 with fracture) were compared for investigation of the difference in BMD values relative to fracture status. The absolute BMD values in Japanese were lower than those in Americans, and the differences were greater with advancing age. The magnitude of the BMD difference was 8.6, 20.5, 38.1 mg/cm³ in women aged 20–24 years, 40–44 years, 60–64 years, respectively. In premenopausal women, BMD began to decrease at the age of 20 in Japanese, whereas the peak bone mass was maintained until the age of 35 in the American women. In immediate postmenopausal women, BMD significantly decreased in both populations. In later postmenopausal women, BMD significantly decreased with age in the Japanese women but decreased less rapidly in the American women. The aging decrease of BMD was 1.4% and 2.2% per year in the later postmenopausal American and Japanese women, respectively. The fracture threshold is considered to be lower in Japanese women. However, the BMD difference between American and Japanese women with fracture was similar to that without fracture. The Z-scores of fracture subjects versus controls were 2.9 in American and 1.8 in Japanese women. In conclusion, Japanese women were found to have a lower BMD and lower fracture threshold than American women. The significant decrease of spinal trabecular BMD in late postmenopause is potentially responsible for the higher prevalence of spinal fracture in Japanese women. Received: 18 December 1995 / Accepted: 23 September 1996     

Effect of antioxidants combined to resistance training on BMD in elderly women: a pilot study

Summary  We determined the effect of antioxidants and resistance training on bone mineral density of postmenopausal women. After 6 months, we observed a significant decrease in the lumbar spine BMD of the placebo group while other groups remained stable. Antioxidants may offer protection against bone loss such as resistance training. Introduction  The purpose of this pilot study was to determine the effects of antioxidant supplements combined to resistance training on bone mineral density (BMD) in healthy elderly women. Methods  Thirty-four postmenopausal women (66.1 ± 3.3 years) were randomized in four groups (placebo, n = 7; antioxidants, n = 8; exercise and placebo, n = 11; and exercise and antioxidants, n = 8). The 6-month intervention consisted in antioxidant supplements (600 mg vitamin E and 1,000 mg vitamin C daily) or resistance exercise (3×/week). Femoral neck and lumbar spine BMD (DXA) and dietary intakes (3-day food record) were measured before and after the intervention. A repeated measure ANOVA and non-parametric Mann–Whitney U tests were used. Results  We observed a significant decrease in the placebo group for lumbar spine BMD (pre, 1.01 ± 0.17 g/cm²; post, 1.00 ± 0.16 g/cm²; P < 0.05 respectively) while it remained stable in all other groups. No changes were observed for femoral neck BMD. Conclusions  Antioxidant vitamins may offer some protection against bone loss in the same extent as resistance exercise although combining both does not seem to produce additional effects. Our results suggest to further investigate the impact of antioxidant supplements on the prevention of osteoporosis.     

Cut-off Values Determined for Vertebral Fracture by Peripheral Quantitative Computed Tomography in Japanese Women

In spite of the benefits of bone mass measurement by dual-energy X-ray absorptiometry (DXA), the use of DXA has limitations. It is unable to assess a true bone density, and cannot discriminate between the trabecular and cortical bone compartments. Ultradistal radius bone density was measured using peripheral quantitative computed tomography (pQCT) to determine reference values for total bone density (BD), trabecular bone density (TBD), polar strength strain index (pSSI), total bone mineral content (BC), trabecular bone mineral content (TBC), cortical bone density (CBD), cortical bone mineral content (CBC) and polar cross-sectional moment of inertia (pCSMI) in the Japanese female population, and to ascertain the cut-off values of the measured indicators that could most efficiently discriminate osteoporotic subjects with vertebral fractures. A total of 5266 healthy Japanese women aged 20–89 years were included in this study to determine Japanese reference values. Additionally, 621 who had undergone radiographic examination of the thoracic and lumbar spine at the time of pQCT measurement were selected to determine the cut-off values of BD, TBD, pSSI and other indicators for vertebral fractures. All the healthy subjects were divided into 5 year age groups. The BD showed nonsignificant changes from the 20–24 year age group to the 45–49 year age group, and fell significantly thereafter. The TBD maintained a plateau until the 40–44 year group, which corresponds to the young adult mean (YAM) values of the lumbar spine, femoral neck and radius BMDs measured using DXA. The TBD decreased significantly thereafter. The pSSI did not change significantly from the 20–24 year age group to the 45–49 year age group, and decreased slightly in the 50–54 year age group and markedly after 55–59 years. The cut-off values for the discrimination of vertebral fractures were obtained by the calculation of sensitivities, specificities and the area under the curves obtained using age-adjusted receiver operating characteristics (ROC) analysis. Odds ratios and 95% confidence limits (CL) were calculated using age-adjusted logistic analysis. The cut-off values for vertebral fractures, the area under the ROC curves (AUC) and odds ratios were 270.1 mg/cm³ (−2.2 SD, 66.6% of YAM), 0.689 ± 0.025, 2.10 (1.63, 2.70) for BD, 104.8 mg/cm³ (−2.2 SD, 53.5% of YAM), 0.699 ± 0.023, 2.17 (1.69, 2.77) for TBD and 192.8 mm³ (−1.9 SD, 59.8% of YAM), 0.631 ± 0.028, 1.72 (1.34, 2.21) for pSSI, respectively. These findings suggest that ultradistal radius BMD measured using pQCT can be used to discriminate women with vertebral fractures. Received: 3 August 2000 / Accepted: 5 March 2001     

Forearm Bone Mineral Densitometry Cannot be Used to Monitor Response to Alendronate Therapy in Postmenopausal Women

Alendronate significantly increases bone mass and reduces hip and spine fractures in postmenopausal women. To determine whether forearm densitometry could be used to monitor the efficacy of alendronate, we examined changes in bone mineral density (BMD) at the forearm (one-third distal, mid-distal, ultradistal radius) versus changes at the hip (femoral neck, total hip) and spine (posteroanterior and lateral) in a double-masked, randomized, placebo-controlled clinical trial of 120 elderly women (mean age 70 ± 4 years) treated with alendronate for 2.5 years. We found that among women in the treatment group, BMD increased by 4.0–12.2% at the hip and spine sites (all p<0.001), whereas BMD increased only nominally at the one-third distal radius (1.3%, p<0.001) and mid-radius (0.8%, p<0.05), and remained stable at the ultradistal radius. At baseline, forearm BMD correlated with that of the hip (r= 0.55–0.64, p<0.001), femoral neck (r= 0.54–0.61, p<0.001) and posteroanterior spine (r= 0.56–0.63, p<0.001). Changes in radial BMD after 1 year of therapy were not correlated with changes in hip and spine BMD after 2.5 years of therapy. In contrast, short-term changes in total hip and spine BMD were generally positively associated with long-term changes in total hip, femoral neck and spine BMD (r= 0.30–0.71, p<0.05). Furthermore, long-term BMD changes at the forearm did not correlate with long-term hip and spine BMD changes, in contrast to the moderate correlations seen between spine and hip BMD at 2.5 years (r= 0.38–0.45, p<0.01). We conclude that neither short- nor long-term changes in forearm BMD predict long-term changes in overall BMD for elderly women on alendronate therapy, suggesting that measurements of clinically relevant central sites (hip and spine) are necessary to assess therapeutic efficacy. Received: 18 February 1999 / Accepted: 20 May 1999     

Changes in Bone Mineral Density with Age in Men and Women: A Longitudinal Study

We performed a prospective study to evaluate the normal changes in bone mineral density (BMD) in the forearm, hip, spine and total body, and to study the agreement between changes in BMD estimated from cross-sectional data and the actual longitudinal changes. Six hundred and twenty subjects (398 women, 222 men; age 20–89 years) without diseases or medication known to affect bone metabolism undertook baseline evaluations, and 525 (336 women, 189 men) completed the study. BMD was measured twice 2 years apart by dual-energy X-ray absorptiometry. From cross-sectional evaluations the only premenopausal bone loss (<0.003 g/cm²/year) was found in the hip. In women after menopause and in men an age-related bone loss (0.002–0.006 g/cm²/year) was found at all sites. The data from the longitudinal evaluation showed a small bone loss in women before menopause at the hip and lumbar spine (<0.4%/year (<0.004 g/cm²/year)); this bone loss nearly tripled in the early postmenopausal years (<10 years since menopause), and thereafter decreased to the premenopausal rate for the hip, and to zero for the lumbar spine. The most pronounced bone loss after menopause occurred in the forearm (1.2 %/year (0.006 g/cm²/year)), and it remained constant throughout life. In men there was a small longitudinal bone loss in the hip throughout life, and a small bone loss in the distal forearm after the age of 50 years. In all groups, except for the early postmenopausal women, we found a small increase in total body BMD with age. When comparing the changes in BMD estimated from cross-sectional data with the longitudinal changes, only the hip and forearm generally displayed agreement, whereas the changes in the total body and spine generally were incongruous. In conclusion, the hip and forearm appear to be the sites with the best agreement between the cross-sectional estimated and the longitudinal age-related changes in BMD. Received: 22 August 2000 / Accepted: 22 June 2001     

Bone density in osteopenic women: A modified distal radius density measurement procedure to develop an “at risk” value for use in screening women

This study measured radial and lumbar spine bone density in postmenopausal white female patients with nontraumatic fractures and their agematched controls. Bone density measurements were made with a single-beam densitometer. Distal radial bone density measurements were made at the site at which the radius and ulna are separated by 5 mm, which is ～5 mm from the distal radioulnar joint. Lumbar spine density was obtained using a dualbeam densitometer. Density at the commonly used “2/3” site near the midradius was also measured. Forty-six crush fracture osteoporotic patients, 35 hip fracture patients, and 20 osteopenic patients referred to the clinic for back pain or excessive bone loss but with no history of nontraumatic fracture were studied. Bone density values at all sites in the patient populations were statistically reduced from control values (p < 0.01). At a mean age of 62 years, density of the midradius was 12% below the control value. However, both vertebral and distal radial densities (“5 mm” site) were 25% below control values. The spine/distal radius ratio remained constant. It was demonstrated that bone density at the modified distal radial site could be used to predict vertebral density in osteopenic patients. An “at risk” value useful in screening procedures was determined as that distal radius density value ?95% of all values from fracture patients—325 mg/cm². It is concluded that distal radial density at the new “5 mm” site can be used in conjunction with midradius density as a preliminary test for both generalized and trabecular bone mass loss in women.