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Summary: Bone microarchitecture by high-resolution peripheral quantitative computed tomography (HR-pQCT) was assessed in adult patients with mild, moderate, and severe osteogenesis imperfecta (OI). The trabecular bone score (TBS), bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA), and dual X-ray and laser (DXL) at the calcaneus were likewise assessed in patients with OI. Trabecular microstructure and BMD in particular were severely altered in patients with OI. Introduction: OI is characterized by high fracture risk but not necessarily by low BMD. The main purpose of this study was to assess bone microarchitecture and BMD at different skeletal sites in different types of OI. Methods: HR-pQCT was performed in 30 patients with OI (mild OI-I, n = 18 (41.8 [34.7, 55.7] years) and moderate to severe OI-III-IV, n = 12 (47.6 [35.3, 58.4] years)) and 30 healthy age-matched controls. TBS, BMD by DXA at the lumbar spine and hip, as well as BMD by DXL at the calcaneus were likewise assessed in patients with OI only. Results: At the radius, significantly lower trabecular parameters including BV/TV ( p = 0.01 and p < 0.0001, respectively) and trabecular number ( p < 0.0001 and p < 0.0001, respectively) as well as an increased inhomogeneity of the trabecular network ( p < 0.0001 and p < 0.0001, respectively) were observed in OI-I and OI-III-IV in comparison to the control group. Similar results for trabecular parameters were found at the tibia. Microstructural parameters were worse in OI-III-IV than in OI-I. No significant differences were found in cortical thickness and cortical porosity between the three subgroups at the radius. The cortical thickness of the tibia was thinner in OI-I ( p < 0.001), but not OI-III-IV, when compared to controls. Conclusions: Trabecular BMD and trabecular bone microstructure in particular are severely altered in patients with clinical OI-I and OI-III-IV. Low TBS and DXL and their significant associations to HR-pQCT parameters of trabecular bone support this conclusion. [ABSTRACT FROM AUTHOR]

Summary: Quantitative ultrasound (QUS) measurement variables vary between European countries in a different way to hip bone mineral density. Standardization of data can be achieved through statistical approaches to reduce any between-center differences in QUS measurement variables. However, further validation of this method is required before it can be widely applied. Introduction: European between-center differences in hip bone mineral density (BMD) have been shown to exist; however, little is known about the geographical heterogeneity of QUS measurement variables. We aimed to examine the differences in QUS variables between three different European countries. Methods: Five calcaneal and phalangeal QUS devices in Sheffield, Aberdeen (UK), Kiel and Berlin (Germany), and three devices in Paris (France) were used to measure QUS variables in younger ( n = 463, 20-39 years old) and older ( n = 2,399, 55-79 years old) women participating in the European multicenter Osteoporosis and Ultrasound (OPUS) study. Broadband ultrasound attenuation, speed of sound, stiffness index, amplitude-dependent speed of sound, bone transmission time, and ultrasonic bone profiler index data were collected. Between-center differences were examined using ANOVA followed by post hoc Fisher's least significant difference tests, and ANCOVA with linear contrasts. p < 0.05 indicated statistical significance. Results: Between-center differences in nonstandardized QUS measurement variables existed for younger ( p = 0.0023 to p < 0.0001) and older women ( p < 0.001). Anthropometric characteristics exerted a significant influence on nonstandardized data ( p = 0.045 to p < 0.001). However, following statistical standardization, based on height and weight or based on measurements made in young people, geographical heterogeneity in QUS measurement variables was no longer apparent. Conclusions: QUS measurement variables vary between European countries in a different way to those for hip BMD. Standardization of data can be achieved through statistical approaches to reduce any between-center differences in QUS measurement variables. However, further validation of this method is required before it can be widely applied. [ABSTRACT FROM AUTHOR]

Summary: Strontium ranelate appears to influence more than alendronate distal tibia bone microstructure as assessed by high-resolution peripheral quantitative computed tomography (HR-pQCT), and biomechanically relevant parameters as assessed by micro-finite element analysis (μFEA), over 2 years, in postmenopausal osteoporotic women. Introduction: Bone microstructure changes are a target in osteoporosis treatment to increase bone strength and reduce fracture risk. Methods: Using HR-pQCT, we investigated the effects on distal tibia and radius microstructure of strontium ranelate (SrRan; 2 g/day) or alendronate (70 mg/week) for 2 years in postmenopausal osteoporotic women. This exploratory randomized, double-blind trial evaluated HR-pQCT and FEA parameters, areal bone mineral density (BMD), and bone turnover markers. Results: In the intention-to-treat population ( n = 83, age: 64 ± 8 years; lumbar T-score: −2.8 ± 0.8 [DXA]), distal tibia Cortical Thickness (CTh) and Density (DCort), and cancellous BV/TV increased by 6.3%, 1.4%, and 2.5%, respectively (all P < 0.005), with SrRan, but not with alendronate (0.9%, 0.4%, and 0.8%, NS) ( P < 0.05 for all above between-group differences). Difference for CTh evaluated with a distance transformation method was close to significance ( P = 0.06). The estimated failure load increased with SrRan (+2.1%, P < 0.005), not with alendronate (−0.6%, NS) (between-group difference, P < 0.01). Cortical stress was lower with SrRan ( P < 0.05); both treatments decreased trabecular stress. At distal radius, there was no between-group difference other than DCort ( P < 0.05). Bone turnover markers decreased with alendronate; bALP increased (+21%) and serum-CTX-I decreased (−1%) after 2 years of SrRan (between-group difference at each time point for both markers, P < 0.0001). Both treatments were well tolerated. Conclusions: Within the constraints of HR-pQCT method, and while a possible artefactual contribution of strontium cannot be quantified, SrRan appeared to influence distal tibia bone microstructure and FEA-determined biomechanical parameters more than alendronate. However, the magnitude of the differences is unclear and requires confirmation with another method. [ABSTRACT FROM AUTHOR]

Summary: Patients in the Health Outcomes and Reduced Incidence with Zoledronic Acid Once Yearly (HORIZON) Recurrent Fracture Trial were assessed for evidence of delayed hip fracture healing. No association was observed between zoledronic acid (ZOL) and delayed healing. We conclude that ZOL has no clinically evident effect on fracture healing, even when the drug is infused in the immediate postoperative period. Introduction: Intravenous zoledronic acid 5 mg (ZOL) given after a hip fracture reduces secondary fracture rates and mortality. It has been postulated that bisphosphonates may affect healing if given soon after a fracture. We sought to determine whether the timing of ZOL infusion affected the risk of delayed hip fracture healing. Methods: In the HORIZON Recurrent Fracture Trial, patients were randomized within 90 days of a low-trauma hip fracture to receive either once-yearly ZOL ( n = 1,065) or placebo ( n = 1,062). Clinical symptoms of delayed hip fracture healing were sought at randomization, 6 months and 12 months after fracture; if present, a central adjudication committee blinded to treatment assignment reviewed radiographs and clinical records. Median follow-up was 1.9 years. Results: The overall incidence of delayed healing was 3.2% (ZOL) and 2.7% (placebo; odds ratio [OR], 1.17; 95% confidence interval [CI], 0.72-1.90; p = 0.61). Logistic regression models revealed no association between ZOL and delayed healing even after adjusting for other risk factors (OR, 1.21; 95% CI, 0.74-1.99; p = 0.44). There was no interaction by timing of infusion, and nonunion rates were similar even when ZOL was given within 2 weeks of hip fracture repair. NSAID use was significantly associated with delayed fracture healing (OR, 2.55; 95% CI, 1.49-4.39; p < 0.001). Conclusions: ZOL has no clinically evident effect on fracture healing, even when the drug is infused in the immediate postoperative period. [ABSTRACT FROM AUTHOR]

Summary: We observed higher proximal femur bone mineral density (BMD) in European women compared to average values derived from US Caucasian women in the National Health and Nutrition Examination Survey (NHANES) study. Across European centres, Parisian women had lower proximal femur BMD compared to women from Kiel or Sheffield. Introduction: Proximal femur BMD of US adults (NHANES III) may not accurately reflect that of European women. We examined the heterogeneity of BMD across European and US Caucasian women and across different European populations. Methods: Proximal femur BMD was measured in women ages 20-39 years ( n = 258) and 55-79 years ( n = 1,426) from three European centres. Cross-calibrated BMD for total hip, femoral neck, trochanter and intertrochanter were examined. International variation in BMD was assessed by comparing means and SDs in the European data with those from the US NHANES III study. European populations were stratified into 5-year age bands to establish individual centre reference intervals. Between-centre differences were assessed using ANOVA and post hoc Fisher's least significant difference tests. Results: European women had higher BMD than US women: The differences were 7.1% to 14.2% ( p < 0.001) and 0% to 3.9% ( p < 0.05) in the older and younger women, respectively. Standard deviations for BMD at the different sites were comparable to those for US women. Among older, but not younger European women, proximal femur BMD was significantly lower in French women (Paris) than in women from Germany (Kiel) or the UK (Sheffield) (difference = 5.0% to 9.6%, p < 0.05). Conclusions: International variation in hip BMD does exist, with international and between-centre differences being less evident at the femoral neck. [ABSTRACT FROM AUTHOR]