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Elevation of homocysteine is associated with an increased risk for bone fractures. Whether the risk is due to homocysteine or to the reduced levels of cofactors necessary for its metabolisation, such as folates or vitamin B12, is not completely clear. In this study we wanted to determine whether in postmenopausal women, levels of folates, homocysteine or vitamin B12 are predictive of the rate of vertebral bone mineral density (BMD) change. The study was conducted at the centre for the menopause of our university hospital. Between September 2001 and March 2002, 161 healthy postmenopausal women volunteered for a cross-sectional evaluation of BMD and levels of serum folates, homocysteine and vitamin B12. Women were recalled for a second evaluation of vertebral BMD after about 5 years. Women having used anti-resorptive therapies for more than 1 year were excluded. The analysis was possible in 117 postmenopausal women. The annual rate of vertebral BMD change was independently related to levels of folates (coefficient of regression (CR): 2.040; 95%CI: 0.483, 3.596; p=0.011), and initial BMD values (CR: -0.060; 95%CI: -0.117, -0.003; p=0.040). No significant relation was found between the change of vertebral BMD and homocysteine or vitamin B12. BMD values at the first (r=0.225; p=0.016) and the second (r=0.206; p=0.027) evaluation were related to levels of folates, but not of homocysteine or of vitamin B12. These data suggest an important role for folates deficiency in the vertebral BMD decline of postmenopausal women.

Aim: To compare the results of ultrasound and computed peripheral tomography in evaluating bone mass in a population of normal children., Methods: Seven hundred and twenty-six healthy school children (260 males; age 8.3-20.9 y) underwent calcaneous ultrasound and peripheral computed tomography at the ultradistal radius. Broadband ultrasound attenuation (BUA) and areal and volumetric bone mineral density (aBMD and vBMD) were evaluated. The results were compared and correlated among them and with auxological parameters (height, BMI and pubertal stages) using the software package SPSS for Windows., Results: The three variables examined (BUA, aBMD and vBMD) all showed a progressive increase with age and a positive correlation with age, height and BMI. When the population was subdivided according to pubertal stages, all variables showed a progressive increase, the difference being significant when stages 1-2 were compared with stages 4-5. A significant correlation was present among BUA, aBMD and vBMD even if the Pearson correlation coefficient was not high., Conclusions: The similar pattern of BUA, aBMD and vBMD with respect to age, height and pubertal stages indicates that ultrasound could be a reliable method to screen bone mass abnormalities in children. The low correlation coefficient, however, suggests that the methods employed measure different bone parameters. Moreover, the different skeletal locations could also account for these results.

Purpose: Non-invasive measurement by peripheral quantitative computed tomography (pQCT) of bone geometry, biomechanics, and mineral content in patients (pts) with primary hyperparathyroidism (PHPT)., Materials and Methods: Total, trabecular and cortical mineral density (totBMD, cortBMD, trab BMD), bone geometrical properties (total area, trabecular area, cortical area, cortical/total area) and cortical thickness as biomechanical parameters, were assessed by pQCT at distal radius in 38 (32 F; 6 M) consecutive patients with PHPT (mean age: 62 yrs; range: 30-77). In a subgroup of 12 patients, bone mineral density (BMD) was also measured by means of dual X-ray absorptiometry (DXA) at the lumbar spine (L2-L4)., Results: Serum biochemical characteristics were: iPTH (269+/-214 pg/ml; range: 107-1438, normal: 30-65), Calcium (11.4+/-1.1 mg/dl; range: 10.6-13.5, normal: 8.1-10.4) and Alkaline Phosphatase (398+/- 392 U/L; range:173-1174, normal: 98-279). Compa-red with 87 healthy age-matched subjects, total, trabecular and cortical bone densities were reduced in all patients (TotBMD: 216+/-92 mg/cm(3) vs ctr 342+/-94, -37%, p<0.05; TrabBMD: 93+/-51 mg/cm(3) vs ctr 140+/-54, -34%, p <0.01; CorBMD: 711+/-178 mg/cm(3) vs ctr 802+/-175, -11%, p<0.02), such as cortical thickness (0.143+/-0.02 cm vs ctr 0.157+/-0.03, -9%, p<0.02). Among geometrical parameters, only cortical/total area was significant different in the two groups (0,29 vs 0.31; p<0.04). A strong correlation was found between peripheral trabecular bone density assessed by pQCT and axial bone mineral density measured by DXA at L2-L4 (r=0.80; p<0.01)., Conclusions: pQCT measurements in PHPT showed: 1) osteopoenia in all bone compartments partly related to age and menopause; 2) reduced cortical density and cortical thickness consistent with "cancellization" of the inner cortex and lower ability of bone to absorb loading forces. DXA measurements showed osteopoenia also at the lumbar spine, a site rich in trabecular bone. PQCT allowing selective assessment of true volumetric cortical and trabecular bone density such as bone geometry, is proposable in clinical practice, in order to evaluate presurgical bone "status" and to monitor the response to parathyroidectomy.

Aim: Non-invasive assessment of bone geometry, biomechanics, and mineral content in postmenopausal women by peripheral quantitative Computed Tomography (pQCT)., Material and Methods: Total, trabecular and cortical mineral density (totBMD, cortBMD, trabBMD), and the geometrical (total area, trabecular area, cortical area) and biomechanical properties of bone (strength-strain index, cortical thickness) were assessed in 93 consecutive post-menopausal women (mean age: 63+/-7 yrs; age at menopause: 49+/-6 yrs; years since menopause: 14+/-9 yrs) by pQCT at the ultradistal radius of non-dominant forearm., Results: Compared with 50 healthy women at peak of bone mass, volumetric total, trabecular and cortical bone densities were significantly reduced in postmenopausal subjects (TotBMD: 318+/-106 mg/cm3 vs ctr 442+/-100, -28%, p<0.001; TrabBMD: 117+/-59 mg/cm3 vs ctr: 203+/-47, -42%, p<0.001; CorBMD: 764+/-159 mg/cm3 vs 921+/-111, -17%, p<0.001). The bone loss was greater in trabecular bone. Cortical area (0.7+/-0,1 cm2 vs ctr: 0.8+/-0.1, -12.5%, p<0.001), cortical thickness (0.151+/-0.02 cm vs ctr: 0.169+/-0.03, -11%, p<0.001), and strength-strain index (686+/-207 mm3 vs ctr: 883+/-165, -22%, p<0.001) were significantly lower in post-menopausal women in comparison with the controls. Years since menopause and age showed a significant negative correlation with bone mineral densities and biomechanical parameters., Conclusions: In post-menopausal women pQCT showed: 1) osteopoenia in all bone compartments, greater at the trabecular level, related to age and years since menopause; 2) reduced cortical density and cortical thickness, consistent with a reduced ability of bone to absorb loading forces; 3) reduced strength-strain index, indicative of inability to adapt to mechanical use and augmented risk for fracture. We conclude that pQCT is a valuable tool for measuring the true volumetric mineral density and the geometrical and biomechanical indexes of bone, which could be proposed in current clinical practice for the assessment of osteoporosis.

Purpose: To evaluate, in a population of young healthy females aged from 8 to 20 years the bone mass peak (or density), the normal ranges versus age and menarche-age using two methods: pQCT (peripheral Quantitative Computed Tomography) and ultrasound absorptiometry., Material and Methods: From 1998 to 2000 selective measurement of Bone Mineral Density (BMD) of trabecular bone at the ultradistal radius using pQCT, BUA (Broad Band Attenuation) and SOS (Speed of Sound) was carried out on 426 healthy females (aged from 8 to 20 years) in north Italy. BMD was measured using a single photon miniaturized tomographic scanner in the ultradistal radius, SOS and BUA were measured at the same time, using a water bath device obtaining parametric bidimensional images of BUA and SOS. The population studied refers to normal females free of bone metabolism alteration, in pre and post-pubertal status., Results: A normal range of BMD, BUA and SOS versus age and menarche age were established. A linear correlation was found between BUA and BMD measured with pQCT. SOS does not show any correlation with BMD. The pre-puberty and the post-puberty groups show statistically significative differences between SOS, BUA and BMD. We found the peak bone density (measured with pQCT) in the trabecular bone at the ultradistal radius at 15 years of age (mean menarche age of 10 years). The same position of the peak was found for BUA, for SOS the situation is not well defined. The analytical fitting of the data highlights a polynomial correlation of BMD vs. age, SOS vs. age, BUA vs. age., Conclusions: It appears that sexual growth influences the position of peak bone density. The results obtained show a statistically significant correlation between BUA and BMD and age, the menarche-age and the period of exposure of bone tissue to oestrogen. After all, pQCT and ultrasound are useful techniques to evaluate bone density and structure also in a growing population. The results of this study show that it is possible to use bidimensional quantitative ultrasound devices in clinical practice also in young populations taking in account age and sexual development.

pQCT is a method which allows the separate determination of cortical and trabecular bone mineral density in the peripheral skeleton. 21 thalassaemic patients (8 females, 13 males) aged from 10 to 32 years, were examined using pQCT at the ultra distal radius to evaluate SSI (Stress-Strain Index). ALP, serum calcium, hydroxyproline, magnesium, IGF-I, and body surface were determined. The results show a good correlation between cortical BMD and age, concentration of hydroxyproline in urine, serum bone Gla protein, body surface index, bone density of trabecular bone and SSI. Good correlation was found between trabecular bone density and age, IGF-I, BGP and PTH, and between SSI and cortical BMD, age and BSI. The linear relationships between age and cortical and trabecular density show an increase of cortical BMD with age and a decrease of trabecular density with age. The same results were obtained considering trabecular and cortical density versus SSI.

The short term results of a prospective dual energy x-ray absorptiometry (DEXA) study of periprosthetic bone remodeling around titanium femoral stems proximally coated with hydroxyapatite are presented. Thirty patients underwent DEXA scanning on the 15th and 45th postoperative days, 12th, 18th postoperative month. DEXA showed global femoral periprosthetic remodeling during the first 18 postoperative months. However, no significant variation in bone mineral density occurred around the lateral metaphyseal regions, where cancellous bone is greatest.

In order to evaluate the possible relationships among hormonal status, physical activity and bone density, we carried out a study on two groups of female athletes engaged in different levels of physical activity. We measured the following hormones: luteinizing hormone (LH), folliculo-stimulating hormone (FSH), 17-beta-oestradiol (E2), progesterone (PRG), prolactin (HPRL), estrone (E1), thyreo-stimulating hormone (TSH), free thyroxine (FT4), and the markers of phosphate-calcium metabolism: calcitonine (CT), parathormone (PTH), and osteocalcine (BGP). We also measured bone mineral density (BMD). All of these variables were related to the amount of work performed during training. The groups were defined as follows: medium workload (group M, n = 10) and heavy workload (group H, n = 20), engaged in 10 and 18 hours of weekly training at 35 and 60 average percent of VO2max, respectively. All of the hormones and the markers of calcium-phosphate metabolism studied were normal; BMD was also normal for all subjects except for two sisters in group M with reduced BMD. The group H athletes with regular menstrual cycles were found to have an upper limit normal BMD. From these data we conclude that in regularly menstruating athletes an increase in BMD induced by heavy physical activity is evident, while in dysmenorrhoeic athletes the effect of physical activity compensates, to some extent, for the hypothetical bone mineral reduction possibly caused by the hormonal imbalance.

This cross-sectional study examined bone abnormalities by digital radiography, bone densitometry and biochemical tests in 44 clinically asymptomatic renal transplant recipients 6-195 months after renal transplantation. Abnormal radiographs were obtained in 40 of the 44 patients. Dual-energy X-ray absorptiometry (DXA) performed at the lumbar spine (L2-L4)/showed a negative Z score in all patients, ranging from -1 to -1.9 in 28 patients and less than -2.0 in 16 patients. The severity of osteopenia increased with the length of time after transplantation and there was a significant correlation with parathyroid hormone values in patients with normal and low glomerular filtration rates. Our data suggest that decreased bone density values (Z score less than -2) are present in about one-third of patients with renal transplants. Bone loss appears to continue after transplantation. Steroid therapy and immunotherapy are probably the cause of this bone loss. Bone mineral measurements alone are helpful in identifying asymptomatic patients with low bone mass after transplantation.

Lumbar bone mass (LBM) determination by quantitative computerized tomography in pre-, peri- and postmenopausal women was utilized to identify subjects at risk to develop osteoporosis. The results were related to determinations of bone metabolic markers (serum osteocalcin and urinary calcium excretion). Osteocalcin was the only metabolic marker which underwent significative changes. However, we found very poor correlations between LBM and metabolic markers and it is concluded that bone mass determination remains the method of choice to select women for preventive therapy.

The authors report the findings of densitometric analysis performed on 25 patients from of 70 to 90 years of age with fractures of the proximal femur. Although bone density decreased progressively with age, there was not a close correlation between bone density and fracture, as the latter occurred even when the densitometric values were relatively high for the patient's sex and age.

The normal ranges and mathematical equations of bone mineral content (BMC), normalized to radial width (BMC/W) vs. age at the distal radius, were obtained by single photon absorptiometry (SPA), and compared in two different normal populations, one of postmenopausal females and the other of control males. The female population included 1359 postmenopausal women, aged 35 to 75 years; normal control males were 162, of the same age. The results obtained in the two groups of patients show a statistically significant (p less than 0.001) correlation between age and BMC/W, expressed in a polinomial third-degree regression. The slope of the regression curves is quite different between males and females: the mean decrement, evaluated from regression polinomial fits, results 0.5% per year for normal females, and 0.3% per year for normal males. The maximum decrement (1% per year) is observed at the mean age of 51 years, which is the average age of peri-menopausal women in our province (Ferrara). The authors believe SPA to be a simple and reliable technique in measuring peripheral bone loss rate. SPA may be useful in the diagnosis and treatment of postmenopausal women, but is not recommended in the short-term follow-up of osteoporosis.

Bone lesions are the main sign of neoplastic proliferation of multiple myeloma (MM), a disseminated malignant disease which originates in, invades and replaces normal bone marrow. The most characteristic radiographic pattern is a focal lytic lesion, well-defined or "punched-out", generally with no surrounding bone reaction. The association is confirmed between MM and osteoporosis, as reduced bone density (osteopenia) and pathologic fractures (ribs, spine). This paper is aimed at evaluating the importance of osteopenia in both diagnosis and prognosis of MM. Eighteen patients affected with MM were examined with quantitative computed tomography (QCT) and dual-energy X-ray absorptiometry (DEXA) for bone densitometry in lumbar spine and proximal femur. The patients (12 males and 6 females) were classified according to Durie's clinical criteria and to the radiographic patterns suggested by Merlini. The results indicate the patients with an advanced clinical stage (III) and scintigraphic expansion of bone marrow to have low densitometric values on both QCT and DEXA. There was substantial agreement between the 2 methods, but DEXA had a higher number of false positives. Instrumental diagnostic protocol may be thus planned as follows: 1) conventional radiography; 2) bone marrow scintigraphy; 3) bone densitometry of lumbar spine, with QCT. The patient is then to be followed with conventional and/or digital radiography in symptomatic locations, and with bone scintigraphy.