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Association between serum bone formation and resorption markers and cortical and trabecular bone loss and the concurrent periosteal apposition in a population-based cohort of 1069 older adults was assessed. BTM levels moderately reflect the cellular events at the endosteal and periosteal surfaces but are not associated with fracture risk.IntroductionWe assessed whether circulating bone formation and resorption markers (BTM) were individual predictors for trabecular and cortical bone loss, periosteal expansion, and fracture risk in older adults aged 66 to 93 years from the AGES-Reykjavik study.MethodsThe sample for the quantitative computed tomography (QCT)-derived cortical and trabecular BMD and periosteal expansion analysis consisted of 1069 participants (474 men and 595 women) who had complete baseline (2002 to 2006) and follow-up (2007 to 2011) hip QCT scans and serum baseline BTM. During the median follow-up of 11.7 years (range 5.4-12.5), 54 (11.4 %) men and 182 (30.6 %) women sustained at least one fracture of any type.ResultsIncrease in BTM levels was associated with faster cortical and trabecular bone loss at the femoral neck and proximal femur in men and women. Higher BTM levels were positively related with periosteal expansion rate at the femoral neck in men. Markers were not associated with fracture risk.ConclusionThis data corroborates the notion from few previous studies that both envelopes are metabolically active and that BTM levels may moderately reflect the cellular events at the endosteal and periosteal surfaces. However, our results do not support the routine use of BTM to assess fracture risk in older men and women. In light of these findings, further studies are justified to examine whether systemic markers of bone turnover might prove useful in monitoring skeletal remodeling events and the effects of current osteoporosis drugs at the periosteum.

UnlabelledLower vitamin D and higher parathyroid hormone (PTH) levels are associated with higher volumetric BMD and bone strength at the lumbar spine as measured by central quantitative computed tomography in primary hyperparathyroidism (PHPT), but there are no differences in bone microarchitecture as measured by trabecular bone score (TBS).IntroductionThe purpose of this study was to evaluate the association between 25-hydroxyvitamin D (25OHD) and volumetric bone mineral density (vBMD) and the TBS at the lumbar spine (LS) in PHPT.MethodsThis is a cross-sectional analysis of PHPT patients with and without low 25OHD. We measured vBMD with quantitative computed tomography (cQCT) and TBS by dual-energy X-ray absorptiometry (DXA) at the LS in 52 and 88 participants, respectively.ResultsIn the cQCT cohort, those with lower vitamin D (

UnlabelledAssociation between serum bone formation and resorption markers and bone mineral, structural, and strength variables derived from quantitative computed tomography (QCT) in a population-based cohort of 1745 older adults was assessed. The association was weak for lumbar spine and femoral neck areal and volumetric bone mineral density.IntroductionThe aim of this study was to examine the relationship between levels of bone turnover markers (BTMs; osteocalcin (OC), C-terminal cross-linking telopeptide of type I collagen (CTX), and procollagen type 1N propeptide (P1NP)) and quantitative computed tomography (QCT)-derived bone density, geometry, and strength indices in the lumbar spine and femoral neck (FN).MethodsA total of 1745 older individuals (773 men and 972 women, aged 66-92 years) from the Age, Gene/Environment Susceptibility (AGES)-Reykjavik cohort were studied. QCT was performed in the lumbar spine and hip to estimate volumetric trabecular, cortical, and integral bone mineral density (BMD), areal BMD, bone geometry, and bone strength indices. Association between BTMs and QCT variables were explored using multivariable linear regression.ResultsMajor findings showed that all BMD measures, FN cortical index, and compressive strength had a low negative correlation with the BTM levels in both men and women. Correlations between BTMs and bone size parameters were minimal or not significant. No associations were found between BTMs and vertebral cross-sectional area in women. BTMs alone accounted for only a relatively small percentage of the bone parameter variance (1-10 %).ConclusionSerum CTX, OC, and P1NP were weakly correlated with lumbar spine and FN areal and volumetric BMD and strength measures. Most of the bone size indices were not associated with BTMs; thus, the selected bone remodeling markers do not reflect periosteal bone formation. These results confirmed the limited ability of the most sensitive established BTMs to predict bone structural integrity in older adults.

Byline: C. L. Gordon (1), T. F. Lang (1), P. Augat (1), H. K. Genant (1) Keywords: Key words:Connectivity -- High-resolution CT -- Trabecular structure -- Vertebral fracture Abstract: The goal of this study was to assess whether a high-resolution CT measure of trabecular bone structure can enhance the discrimination between subjects with or without a vertebral fracture and having overall low hip or spine bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA). Sixty-one women with low BMD by DXA (T-score &lt --2.5 at hip or spine) were examined. Twenty women had sustained a vertebral fracture. Quantitative CT (QCT) BMD and high-resolution CT spinal scans were performed on a whole-body CT scanner. For the high-resolution images (0.31 mm pixel, 1.5 mm thick slice), trabecular bone was segmented from marrow using an adaptive threshold, region growth and skeletonization step. From the processed image we measured the apparent trabecular bone fraction (BV/TV), apparent trabecular thickness (I.Th) and apparent trabecular spacing (I.Sp). We also assessed the connectivity of the marrow space using region growing to derive a mean (H.sub.A) and maximum (H.sub.M) hole size. Despite the fact that the study population was preselected to have a low BMD by DXA, QCT BMD was highly associated with (p &lt 0.005) with fracture status. All structural parameters were correlated (r ~ 0.64 to 0.79) with BMD with p &lt 0.003 and showed significant differences between the fracture and non-fracture group. However, except for H.sub.A, this difference did not remain significant after adjustment for BMD. When BMD and then H.sub.A was entered into a paired linear regression model to predict fracture outcome, H.sub.A contributed with p= 0.03 and BMD with p= 0.86. ROC analysis was applied and showed that H.sub.A, BMD, I.Th and I.Sp discriminated the two groups with areas of 0.76, 0.75, 0.71 and 0.68, respectively. These findings suggest that an assessment of vertebral trabecular structure from high-resolution CT images is useful in discriminating subjects with vertebral fractures and potentially useful for predicting future fractures. Author Affiliation: (1) Osteoporosis and Arthritis Research Group, Department of Radiology, University of California, San Francisco, USA, US Article note: Received: 10 October 1997 / Accepted: 4 December 1997

Byline: M. Takada (1), C. Y. Wu (1), T. F. Lang (1), H. K. Genant (1) Keywords: Key words:Computed tomography -- Osteoporosis -- Radiograph -- Scoutview -- Semiquantitative technique -- Vertebral fracture assessment Abstract: Semiquantitative vertebral fracture assessment was compared between lateral computed tomography (CT) scoutviews and conventional thoracolumbar spinal radiographs. Vertebral levels T4--L4 were assessed by both techniques in a group of 56 women (mean age 60 + 13 years). In order to compare inter- and intra-observer variabilities for the two techniques, the images were analyzed twice by two independent observers, and percentage agreement and kappa statistics were measured both between readings and between observers. Percentage agreement and kappa statistics were also used to quantify differences between techniques. In the CT scoutviews, noise and artifacts from overlying tissues in the thoracic spinal levels rendered 3.4% of the vertebrae unreadable for the first observer and 8.3% for the second observer. For the CT scoutviews the agreement between readings was 98.1%, 97.3% and 100% (k = 0.87, 0.83 and 1.0) on T4--L12, T4--12 and L1--4, respectively for the first observer, and 97.8%, 97.1% and 99.5% (k = 0.79, 0.73 and 0.92) for the second observer. For the lateral radiographs, the agreement between readings was 97.7%, 96.9% and 100% (k = 0.87, 0.85 and 1.0) on T4--L12, T4--12 and L1--4, respectively for the first observer, and 98.4%, 97.7% and 99.5% (k = 0.86, 0.82 and 0.95) for the second observer. The agreement between observers was 96.1%, 94.4% and 100% (k = 0.68, 0.58 and 1.0) on T4--L12, T4--12 and L1--4, respectively for the CT scout-views and 96.8%, 95.9% and 99.0% (k = 0.79, 0.76 and 0.91) for the lateral radiographs. The inter-technique was 95.8%, 94.2% and 99.5% (k = 0.73, 0.68 and 0.95) on T4--L12, T4--12 and L1--4, respectively for the first observer and 95.6%, 94.2% and 99.0% (k = 0.64, 0.55 and 0.90) for the second observer, with the scoutview technique detecting, on average, 23% fewer fractures than the lateral radiographs. Although the vertebral fracture detection in lumbar spine is quite comparable to that of conventional radiographs, given its reduced sensitivity for vertebral fracture detection in thoracic spine, the lateral CT scoutview technique should not be substituted for conventional radiographs where diagnosis of all vertebral fractures is of primary importance. Author Affiliation: (1) Osteoporosis Research Group, Department of Radiology, University of California San Francisco, California, USA, US Article note: Received: 26 August 1997 / Accepted: 28 Augustr 1997

Summary: Information on bone loss in treated non-Hodgkin's lymphoma patients is limited. In this study, we used CT to analyze bone loss as well as prevalent and incident fractures. We found severe bone loss, a high rate of fractures, and a novel association between bone loss and the international prognostic index. Introduction: To investigate bone loss and fracture risk in non-Hodgkin-lymphoma (NHL) patients by (i) comparing treatment-related vertebral density (VD) loss in NHL patients with control subjects and (ii) investigating associations of VD loss versus fracture risk. Further, associations of VD loss and clinical parameters were investigated. Methods: VD of 123 NHL patients was measured pre- and post-treatment in the L1, L2, and L3 vertebrae in routine computed tomography (CT) scans, performed between Jan 2016 and Mar 2017. Control measurements (n = 52) were obtained from CT colonographies between Sept 2003 and Sept 2017 and their subsequent follow-up-exams (10–137 months). Prevalent and incident (between baseline and follow-up) fractures were assessed in all subjects, and VD loss per year was calculated. Linear regression models were used to (i) compare VD loss between patients and controls and (ii) identify associations between VD loss and clinical parameters. Using logistic regression models, ORs for fractures per SD change in VD were assessed in patients. Analyses were adjusted for age, sex, and contrast application. Results: NHL patients experienced significantly greater VDL1–3 loss than controls (P = 0.003), and greater VDL1–3 loss was associated with a greater likelihood of incident fractures (OR, [95%-CI], P 1.90, [1.03, 3.51], 0.04). Patients with an initial international prognostic index (IPI) of 5 suffered significantly greater VD loss compared with an IPI of 0 (P = 0.01). Conclusion: Using VD measurements in routine CT scans, substantial vertebral bone loss in NHL patients could be documented with a high incidence of fractures. [ABSTRACT FROM AUTHOR]

Summary: In this study, we determined that operator positioning precision contributes significant measurement error in high-resolution peripheral quantitative computed tomography (HR-pQCT). Moreover, we developed software to quantify intra- and inter-operator variability and demonstrated that standard positioning training (now available as a web-based application) can significantly reduce inter-operator variability. Introduction: HR-pQCT is increasingly used to assess bone quality, fracture risk, and anti-fracture interventions. The contribution of the operator has not been adequately accounted in measurement precision. Operators acquire a 2D projection ('scout view image') and define the region to be scanned by positioning a 'reference line' on a standard anatomical landmark. In this study, we (i) evaluated the contribution of positioning variability to in vivo measurement precision, (ii) measured intra- and inter-operator positioning variability, and (iii) tested if custom training software led to superior reproducibility in new operators compared to experienced operators. Methods: To evaluate the operator in vivo measurement precision, we compared precision errors calculated in 64 co-registered and non-co-registered scan-rescan images. To quantify operator variability, we developed software that simulates the positioning process of the scanner's software. Eight experienced operators positioned reference lines on scout view images designed to test intra- and inter-operator reproducibility. Finally, we developed modules for training and evaluation of reference line positioning. We enrolled six new operators to participate in a common training, followed by the same reproducibility experiments performed by the experienced group. Results: In vivo precision errors were up to threefold greater (Tt.BMD and Ct.Th) when variability in scan positioning was included. The inter-operator precision errors were significantly greater than the short-term intra-operator precision ( p < 0.001). New trained operators achieved comparable intra-operator reproducibility to experienced operators and lower inter-operator reproducibility ( p < 0.001). Precision errors were significantly greater for the radius than for the tibia. Conclusion: Operator reference line positioning contributes significantly to in vivo measurement precision and is significantly greater for multi-operator datasets. Inter-operator variability can be significantly reduced using a systematic training platform, now available online (). [ABSTRACT FROM AUTHOR]

Summary: This study evaluated racial differences in bone size and volumetric density at the spine and hip in pre- and postmenopausal Chinese American and White women. Compared with White women, Chinese American women have greater cortical volumetric bone density (vBMD) at the hip, congruent with the results at the peripheral skeleton. Introduction: Chinese American women have lower rates of fracture than White women despite lower areal bone density. At the forearm and tibia, however, Chinese American women have higher cortical vBMD as well as greater trabecular and cortical thickness, but smaller bone area as measured by high-resolution peripheral quantitative computed tomography (HR-pQCT) compared with White women. Since HR-pQCT data are obtained at peripheral sites, it is unclear whether these differences are relevant to the clinically important lumbar spine and hip. This study assesses racial differences in bone size and vBMD at the spine and hip in Chinese American and White women. Methods: QCT of the spine and hip was measured to assess racial differences in bone size, structure, and vBMD in pre- ( n = 83) and postmenopausal ( n = 50) Chinese American and White women. Data were adjusted for weight, height, physical activity, total calcium intake, parathyroid hormone, and 25-hydroxyvitamin D levels. Results: Among premenopausal women, lumbar spine trabecular vBMD was 5.8% greater in Chinese American versus White women ( p = 0.01). At the hip, cortical vBMD was 3% greater at the femoral neck ( p = 0.05) and 3.6% greater at the total hip ( p = 0.01) in premenopausal Chinese American compared with White women. Among postmenopausal women, there was no difference in lumbar spine trabecular vBMD. Cortical vBMD was 4% greater at the total hip ( p = 0.02) and tended to be greater at the femoral neck ( p = 0.058) in Chinese American versus White women. Conclusions: Consistent with earlier findings in the peripheral skeleton, cortical vBMD is greater at the hip in Chinese American versus White women. [ABSTRACT FROM AUTHOR]