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OBJECTIVE: This study was undertaken to assess the effect of strontium ranelate on nonvertebral and vertebral fractures in postmenopausal women with osteoporosis in a 5-year, double-blind, placebo-controlled trial. METHODS: A total of 5,091 postmenopausal women with osteoporosis were randomized to receive either strontium ranelate at 2 gm/day or placebo for 5 years. The main efficacy criterion was the incidence of nonvertebral fractures. In addition, incidence of hip fractures was assessed, by post hoc analysis, in the subset of 1,128 patients who were at high risk of fractures (age 74 years or older with lumbar spine and femoral neck bone mineral density T scores -2.4 or less). The incidence of new vertebral fractures was assessed, using the semiquantitative method described by Genant, in the 3,646 patients in whom spinal radiography (a nonmandatory procedure) was performed during the course of the study. Fracture data were analyzed using the Kaplan-Meier survival method. RESULTS: Of the 5,091 patients, 2,714 (53%) completed the study up to 5 years. The risk of nonvertebral fracture was reduced by 15% in the strontium ranelate group compared with the placebo group (relative risk 0.85 [95% confidence interval 0.73-0.99]). The risk of hip fracture was decreased by 43% (relative risk 0.57 [95% confidence interval 0.33-0.97]), and the risk of vertebral fracture was decreased by 24% (relative risk 0.76 [95% CI 0.65-0.88]) in the strontium ranelate group. After 5 years, the safety profile of strontium ranelate remained unchanged compared with the 3-year findings. CONCLUSION: Our findings indicate that treatment of postmenopausal osteoporosis with strontium ranelate results in a sustained reduction in the incidence of osteoporotic nonvertebral fractures, including hip fractures, and vertebral fractures over 5 years. [ABSTRACT FROM AUTHOR]

Preclinical studies indicate that strontium ranelate (SrRan) induces opposite effects on bone osteoblasts and osteoclasts, suggesting that SrRan may have a dual action on both formation and resorption. By contrast, alendronate (ALN) is a potent antiresorptive agent. In this multicenter, international, double-blind, controlled study conducted in 387 postmenopausal women with osteoporosis, transiliac bone biopsies were performed at baseline and after 6 or 12 months of treatment with either SrRan 2 g per day (n = 256) or alendronate 70 mg per week (n = 131). No deleterious effect on mineralization of SrRan or ALN was observed. In the intention-to-treat (ITT) population (268 patients with paired biopsy specimens), changes in static and dynamic bone formation parameters were always significantly higher with ALN compared with SrRan at month 6 (M6) and month 12 (M12). Static parameters of formation were maintained between baseline and the last value with SrRan, except for osteoblast surfaces, which decreased at M6. Significant decreases in the dynamic parameters of formation (mineralizing surface, bone formation rate, adjusted apposition rate, activation frequency) were noted at M6 and M12 in SrRan. Compared with ALN, the bone formation parameters at M6 and M12 were always significantly higher (p < 0.001) with SrRan. ALN, but not SrRan, decreased resorption parameters. Compared with the baseline paired biopsy specimens, wall thickness was significantly decreased at M6 but not at M12 and cancellous bone structure parameters (trabecular bone volume, trabecular thickness, trabecular number, number of nodes/tissue volume) were significantly decreased at M12 with SrRan; none of these changes were significantly different from ALN. In conclusion, this large controlled paired biopsy study over 1 year shows that the bone formation remains higher with a lower diminution of the bone remodeling with SrRan versus ALN. From these results, SrRan did not show a significant anabolic action on bone remodeling., (© 2014 American Society for Bone and Mineral Research.)

Background: The results of meta-analyses examining the relationship between vitamin D supplementation and fracture reduction have been inconsistent., Methods: We pooled participant-level data from 11 double-blind, randomized, controlled trials of oral vitamin D supplementation (daily, weekly, or every 4 months), with or without calcium, as compared with placebo or calcium alone in persons 65 years of age or older. Primary end points were the incidence of hip and any nonvertebral fractures according to Cox regression analyses, with adjustment for age group, sex, type of dwelling, and study. Our primary aim was to compare data from quartiles of actual intake of vitamin D (including each individual participant's adherence to the treatment and supplement use outside the study protocol) in the treatment groups of all trials with data from the control groups., Results: We included 31,022 persons (mean age, 76 years; 91% women) with 1111 incident hip fractures and 3770 nonvertebral fractures. Participants who were randomly assigned to receive vitamin D, as compared with those assigned to control groups, had a nonsignificant 10% reduction in the risk of hip fracture (hazard ratio, 0.90; 95% confidence interval [CI], 0.80 to 1.01) and a 7% reduction in the risk of nonvertebral fracture (hazard ratio, 0.93; 95% CI, 0.87 to 0.99). By quartiles of actual intake, reduction in the risk of fracture was shown only at the highest intake level (median, 800 IU daily; range, 792 to 2000), with a 30% reduction in the risk of hip fracture (hazard ratio, 0.70; 95% CI, 0.58 to 0.86) and a 14% reduction in the risk of any nonvertebral fracture (hazard ratio, 0.86; 95% CI, 0.76 to 0.96). Benefits at the highest level of vitamin D intake were fairly consistent across subgroups defined by age group, type of dwelling, baseline 25-hydroxyvitamin D level, and additional calcium intake., Conclusions: High-dose vitamin D supplementation (≥800 IU daily) was somewhat favorable in the prevention of hip fracture and any nonvertebral fracture in persons 65 years of age or older. (Funded by the Swiss National Foundations and others.).

Objective: To investigate interactions between strontium (Sr) and bone mineral and its effects on mineralization in osteoporotic women treated long-term with Sr ranelate (SrRan)., Design: In this study, 34 iliac bone biopsies were analyzed after 2, 12, 24, 36, 48, and 60 months of treatment with SrRan., Methods: Sr global distribution was analyzed by X-ray cartography and the percentage of bone area containing Sr was calculated in the bone samples. The focal distribution of Sr in all bone samples was investigated by X-ray microanalysis. The degree of mineralization was assessed by quantitative microradiography., Results: Absent from old bone formed before the beginning of treatment, Sr was exclusively present in bone formed during this treatment with a much higher focal Sr content in new bone structural units than in old ones. A progressive increase in the extent of areas containing Sr was observed during treatment. The focal bone Sr content in recently formed bone was constant over treatment. Secondary mineralization was maintained at a normal level during treatment., Conclusion: Thus, the quality of bone mineralization (density and heterogeneity at tissue level) was preserved after a long-term treatment with SrRan.

Unlabelled: In postmenopausal osteoporotic women and up to 3 years of treatment with strontium ranelate, strontium was present only in recently deposited bone tissue resulting from formation activity during the period of treatment. Strontium was shown to be dose-dependently deposited into this newly formed bone with preservation of the mineralization., Introduction: Interactions between strontium (Sr) and bone mineral and its effects on mineralization were investigated in women treated with strontium ranelate., Methods: Bone biopsies from osteoporotic women were obtained over 5-year strontium ranelate treatment from phases II and III studies. Bone samples obtained over 3-year treatment were investigated by X-ray microanalysis for bone Sr uptake and focal distribution, and by quantitative microradiography for degree of mineralization. On some samples, Sr distribution (X-ray cartography) was analyzed on whole sample surfaces and the percentage of bone surface containing Sr was calculated. Bone Sr content was chemically measured on whole samples., Results: In treated women, Sr was exclusively present in bone formed during treatment; Sr deposition depended on the dose with higher focal content in new bone structural units than in old ones constantly devoid of Sr, even after 3-year treatment. A plateau in global bone Sr content was reached after 3 years of treatment. Cartography illustrated the extent of surfaces containing Sr, and formation activity during strontium ranelate treatment was higher in cancellous than in cortical bone. Mineralization was maintained during treatment., Conclusion: The quality of bone mineral was preserved after treatment with strontium ranelate, supporting the safety of this agent at the bone tissue level.

Bone mineral is a major determinant of the mechanical resistance of bones. In bone structural units (BSUs), mineralization of osteoid tissue begins with a rapid primary mineralization followed by a secondary mineralization phase, i.e., a slow and gradual maturation of the mineral component leading to complete mineralization during an unknown period. The aim of this study was to determine the chronology of secondary bone mineralization in ewes, an animal model with a remodeling activity close to humans. Eighteen ewes received different fluorescent labels every 6 months to date the "age" of each labeled BSU. The degree of mineralization of bone (DMB) and Vickers microhardness were measured in labeled BSUs, while mineralization at the crystal level was assessed by Fourier transform infrared microspectroscopy (FTIRM). During the first 6 months of mineralization, degree of mineralization and microhardness significantly increased. They then increased more slowly until at 30 months they reach their maximal values. This progression during secondary mineralization was associated with an improvement of both the maturation and the crystal perfection of the mineral part of bone matrix. Finally, secondary mineralization in BSUs is completed after a period of 30 months. This observation should be taken into account for understanding the effects of long-term treatments of bone diseases., (Copyright 2009 Elsevier Inc. All rights reserved.)

Introduction: In adult aromatase-deficient men, estrogen treatment has always resulted in a rapid skeletal maturation with epiphyseal closure and improved BMD. Raloxifene is a SERM with proven estrogen agonist action on bone that leads to an improvement in BMD and a reduction in bone turnover. The present study reports the effects of raloxifene and transdermal estradiol treatment, respectively, on epiphyseal closure and BMD in an aromatase-deficient man, over a 24-month follow-up, with the aim of obtaining further insight into the role of estrogens in the male skeletal homeostasis., Materials and Methods: A 25-year-old Caucasian man with aromatase deficiency, a bone age of 15.3 years, unfused epiphyses and an impaired BMD was initially administered raloxifene (60 mg/day per os) for 12 months, while transdermal estradiol (25 microg twice weekly) was administered for the subsequent 12 months. During the follow-up, the effects of the two treatments on epiphyseal closure, BMD and bone turnover markers were investigated. An iliac crest bone biopsy was performed only before and after the raloxifene treatment, but it was not repeated after transdermal estradiol treatment., Results: No changes in bone age were observed after raloxifene therapy, whereas a complete epiphyseal closure was achieved with transdermal estradiol treatment. Compared with baseline values, raloxifene treatment led to improved BMD both at the ultradistal forearm and 33% radius; the transdermal estradiol treatment resulted in a further slight increase in BMD at the 33% radius, but not at the ultradistal forearm. The baseline bone biopsy showed elevated bone remodelling in trabecular bone, while the second biopsy following raloxifene treatment revealed a decrease in remodelling., Discussion: This study shows that the management of aromatase deficiency in the male cannot consider raloxifene as a first choice treatment, but should be still based on estrogen replacement treatment since in this patient the completion of bone maturation has only been obtained once estradiol substitution was performed. The present case also demonstrates that raloxifene is able to improve BMD in aromatase-deficient men.

Summary: Vertebral fractures are a major adverse consequence of osteoporosis. In a large placebo-controlled trial in postmenopausal women with osteoporosis, strontium ranelate reduced vertebral fracture risk by 33% over 4 years, confirming the role of strontium ranelate as an effective long-term treatment in osteoporosis., Introduction: Osteoporotic vertebral fractures are associated with increased mortality, morbidity, and loss of quality-of-life (QoL). Strontium ranelate (2 g/day) was shown to prevent bone loss, increase bone strength, and reduce vertebral and peripheral fractures. The preplanned aim of this study was to evaluate long-term efficacy and safety of strontium ranelate., Methods: A total of 1,649 postmenopausal osteoporotic women were randomized to strontium ranelate or placebo for 4 years, followed by a 1-year treatment-switch period for half of the patients. Primary efficacy criterion was incidence of patients with new vertebral fractures over 4 years. Lumbar bone mineral density (BMD) and QoL were also evaluated., Results: Over 4 years, risk of vertebral fracture was reduced by 33% with strontium ranelate (risk reduction = 0.67, p < 0.001). Among patients with two or more prevalent vertebral fractures, risk reduction was 36% (p < 0.001). QoL, assessed by the QUALIOST(R), was significantly better (p = 0.025), and patients without back pain were greater (p = 0.005) with strontium ranelate than placebo over 4 years. Lumbar BMD increased over 5 years in patients who continued with strontium ranelate, while it decreased in patients who switched to placebo. Emergent adverse events were similar between groups., Conclusion: In this 4- and 5-year study, strontium ranelate is an effective and safe treatment for long-term treatment of osteoporosis in postmenopausal women.

Degree of mineralization of bone (DMB) is a major intrinsic determinant of bone strength at the tissue level but its contribution to the microhardness (Vickers indentation) at the intermediary level of organization of bone tissue, i.e., Bone Structural Units (BSUs), has never been assessed. The purpose of this study was to analyze the relationship between the microhardness, the DMB and the organic matrix, measured in BSUs from human iliac bone biopsies. Iliac bone samples from controls and osteoporotic patients (men and women), embedded in methyl methacrylate, were used. Using a Vickers indenter, microhardness (kg/mm2) was measured, either globally on surfaced blocks or focally on 100 microm-thick sections from bone samples (load of 25 g applied during 10 sec; CV=5%). The Vickers indenter was more suited than the Knoop indenter for a tissue like bone in which components are diversely oriented. Quantitative microradiography performed on 100 microm-thick sections, allowed measurement of parameters reflecting the DMB (g/cm3). Assessed on the whole bone sample, both microhardness and DMB were significantly lower (-10% and -7%, respectively) in osteoporotic patients versus controls (p<0.001). When measured separately at the BSU level, there were significant positive correlations between microhardness and DMB in controls (r2=0.36, p<0.0001) and osteoporotic patients (r2=0.43, p<0.0001). Mineralization is an important determinant of the microhardness, but did not explain all of its variance. To highlight the role of the organic matrix in bone quality, microhardness of both osteoid and adjacent calcified matrix were measured in iliac samples from subjects with osteomalacia. Microhardness of organic matrix is 3-fold lower than the microhardness of calcified tissue. In human calcanei, microhardness was significantly correlated with DMB (r2=0.33, p=0.02) and apparent Young's modulus (r2=0.26, p=0.03). In conclusion, bone microhardness measured by Vickers indentation is an interesting methodology for the evaluation of bone strength and its determinants at the BSU level. Bone microhardness is linked to Young's modulus of bone and is strongly correlated to mineralization, but the organic matrix accounts for about one third of its variance.

Unlabelled: Strontium ranelate reduces the risk of fracture in post-menopausal osteoporotic women with prevalent fractures for whom quality of life is severely impaired. The SOTI study, which used the SF-36 questionnaire and disease-specific QUALIOST module, demonstrated that treatment with strontium ranelate improved osteoporotic women's quality of life compared with placebo., Introduction: The Spinal Osteoporosis Therapeutic Intervention (SOTI) study demonstrated the effect of orally administered strontium ranelate versus placebo on the incidence of new vertebral fractures and compared impact on quality of life (QoL)., Methods: QoL was assessed 6 monthly over 3 years using the QUALIOST and SF-36 questionnaires in post-menopausal osteoporotic women with prevalent fracture taking strontium ranelate or placebo 2 g/day. A total of 1,240 women were included (strontium ranelate: n=618 and placebo: n=622)., Results: The QUALIOST total score decreased in the strontium ranelate group, indicating preserved QoL compared with a deterioration in the placebo group (P=0.016). Strontium ranelate patients had reduced QUALIOST emotional and physical dimension scores (P=0.019 and 0.032, respectively, versus placebo), indicating beneficial effects on emotional and physical functioning. There was a trend towards better SF-36 scores in the strontium ranelate group, although there were no significant between-group differences. More strontium ranelate patients (+31%) were free from back pain over 3 years versus placebo (P=0.005), with a significant effect from the first year of treatment (P=0.023)., Conclusion: Strontium ranelate has beneficial effects on QoL in women with post-menopausal osteoporosis compared with placebo.

Unlabelled: Strontium ranelate is a new anti-osteoporotic treatment. On bone biopsies collected from humans receiving long-term treatment over 5 yr, it has been shown that strontium ranelate has good bone safety and better results than placebo on 3D microarchitecture. Hence, these effects may explain the decreased fracture rate., Introduction: Strontium ranelate's mode of action involving dissociation of bone formation and resorption was shown in preclinical studies and could explain its antifracture efficacy in humans., Materials and Methods: One hundred forty-one transiliac bone biopsies were obtained from 133 postmenopausal osteoporotic women: 49 biopsies after 1-5 yr of 2 g/d strontium ranelate and 92 biopsies at baseline or after 1-5 yr of placebo., Results and Conclusions: Histomorphometry provided a 2D demonstration of the bone safety of strontium ranelate, with significantly higher mineral apposition rate (MAR) in cancellous bone (+9% versus control, p = 0.019) and borderline higher in cortical bone (+10%, p = 0.056). Osteoblast surfaces were significantly higher (+38% versus control, p = 0.047). 3D analysis of 3-yr biopsies with treatment (20 biopsies) and placebo (21 biopsies) using microCT showed significant changes in microarchitecture with, in the strontium ranelate group, higher cortical thickness (+18%, p = 0.008) and trabecular number (+14%, p = 0.05), and lower structure model index (-22%, p = 0.01) and trabecular separation (-16%, p = 0.04), with no change in cortical porosity. The changes in 3D microarchitecture may enhance bone biomechanical competence and explain the decreased fracture rate with strontium ranelate.