Half the burden of fragility fractures in the community occur in women without osteoporosis. When is fracture prevention cost-effective?

Screening for Osteoporosis to Prevent Fractures: US Preventive Services Task Force Recommendation Statement

Importance

Osteoporotic fractures are associated with psychological distress, subsequent fractures, loss of independence, reduced ability to perform activities of daily living, and death.

Objective

The US Preventive Services Task Force (USPSTF) commissioned a systematic review to evaluate the evidence on the benefits and harms of screening for osteoporosis to prevent fractures in adults 40 years or older with no known diagnosis of osteoporosis or history of fragility fracture.

Population

Adults 40 years or older without known osteoporosis or history of fragility fractures.

Evidence Assessment

The USPSTF concludes with moderate certainty that screening for osteoporosis to prevent osteoporotic fractures in women 65 years or older has moderate net benefit. The USPSTF concludes with moderate certainty that screening for osteoporosis to prevent osteoporotic fractures in postmenopausal women younger than 65 years at increased risk has moderate net benefit. The USPSTF concludes that the evidence is insufficient and the balance of benefits and harms for screening for osteoporosis to prevent osteoporotic fractures in men cannot be determined.

Recommendation

The USPSTF recommends screening for osteoporosis to prevent osteoporotic fractures in women 65 years or older. (B recommendation) The USPSTF recommends screening for osteoporosis to prevent osteoporotic fractures in postmenopausal women younger than 65 years who are at increased risk for an osteoporotic fracture as estimated by clinical risk assessment. (B recommendation) The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for osteoporosis to prevent osteoporotic fractures in men. (I statement).

Disc degeneration influences the strain magnitude and stress distribution within the adjacent trabecular bone

Introduction

Up to one in five will suffer from osteoporotic vertebral fracture within their lifetime. Accurate fracture prediction poses challenges using bone mineral density (BMD) measures. Trabecular bone strains may be influenced by the underlying intervertebral disc (IVD). Understanding how disc degeneration alters load distribution to the vertebra may demonstrate that supplementing fracture risk tools with IVD metrics could improve predictions. The aim of this study was to assess the influence of IVD degeneration on the stress and strain magnitude and distribution in the trabecular bone of adjacent vertebrae.

Methods

Ten human cadaveric lumbar bi-segment specimens (20 IVDs, 9 degenerated, 11 non-degenerated) were µCT-imaged under 1000N. Digital volume correlation was used to quantify axial, principal, maximum shear, and von Mises strain in the superior and inferior regions of the vertebra. Volumetric BMD from quantitative-CT was used to calculate Young's modulus, which was then registered with the von Mises strain field to calculate internal von Mises stress.

Results

Two bi-segments fractured during mechanical testing, resulting in N = 8 endplate regions per group. Trabecular bone adjacent to degenerated IVDs presented higher maximum principal and shear strains in the anterior region, relative to non-degenerated (peak ε1: 6,020 ± 1,633 µε versus 3,737 ± 1,548 µε, p < 0.01; peak γmax: 6,202 ± 1948 µε versus 3,938 ± 2086 µε, p < 0.01). Von Mises stress distribution was significantly skewed towards the anterior region in the degenerated group only (28.3% ± 10.4%, p < 0.05). Reduced disc height correlated with increased central-region axial compressive strain, decreased central-region BMD, and increased anterior region von Mises stress (all p < 0.05).

Discussion

Disc degeneration may encourage high strains to be experienced within the anterior region of the adjacent bone, owing to changes in load distribution. This study demonstrates the potential of utilising IVD metrics in fracture risk assessment, to inform clinical decision making and preventative treatment.

Hip structure and incident fracture: a time-updating survival analysis over 20 years of data from the Geelong Osteoporosis Study

Hip structural analysis parameters are associated with risk of fracture in women across a long follow-up period, with buckling ratio persisting independent of total hip BMD.

PURPOSE

Hip structural analysis (HSA) uses dual X-ray absorptiometry (DXA) hip scans to calculate geometries of narrow neck (NN), intertrochanter (IT), and shaft (S), which may complement bone mineral density (BMD) for assessing fracture risk. We aimed to determine whether HSA parameters were associated with fracture.

METHODS

Participants were women (n = 986, ages 40-94 year) from the Geelong Osteoporosis Study. HSA was calculated from Lunar DPX-L scans. Low-trauma incident fractures were identified radiologically. Participants were followed from baseline to first fracture, death, or end of follow-up period (31/12/16) (13,487 person-years follow-up). Time-updating Cox-proportional hazards modelling investigated associations between HSA parameters and fracture.

RESULTS

Three hundred thirty-five participants reported fractures (rate: 24.99/1000 person-years [95% CI 22.46-27.80]). Higher NN BMD (HR:0.12, 95% CI:0.05-0.29), cross-sectional area (CSA) (0.37, 0.26-0.52), cross-sectional moment of inertia (CSMI) (0.66, 0.50-0.89), section modulus (SM) (0.40, 0.24-0.68) and cortical thickness (CT) (0.00, 0.00-0.01 due to rounding) were associated with decreased risk. IT BMD (0.08, 0.04-0.20), CSA (0.58, 0.49-0.69), CSMI (0.90, 0.85-0.94), and SM (0.69, 0.59-0.81) were similarly associated. Decreased risk was observed at increased values of S BMD (0.20, 0.10-0.38), CSA (0.60, 0.47-0.76), SM (0.60, 0.43-0.83), and CT (0.03, 0.01-0.14). Higher S endocortical diameter (1.81, 1.29-2.53), and buckling ratio (BR) at all sites (NN: 1.07, 1.04-1.11; IT: 1.08, 1.05-1.11, S: 1.31, 1.19-1.46) were associated with increased risk. After adjustment for total hip BMD, the associations with BR at the shaft (1.14, 1.00-1.30) were sustained. Other associations were attenuated.

CONCLUSION

A greater shaft buckling ratio was associated with an increased risk for fracture, independent of total hip BMD.

Are Radiographic Changes in the Mandibular Canal Associated With Bone Mineral Density?

BACKGROUND

Osteoporosis, highly prevalent among postmenopausal women, significantly reduces bone density and increases the risk of fractures. Cortical bone, which constitutes the largest calcium deposit in the human skeleton, is primarily affected in various conditions, including osteoporosis. Due to its visibility in panoramic radiography, the cortical area of the mandibular canal could be valuable in assessing decreases in bone mineral density (BMD).

PURPOSE

The study aimed to characterize and compare changes in the cortices of the mandibular canal between normal, osteopenic, and osteoporotic postmenopausal women.

STUDY DESIGN, SETTING, SAMPLE

Our cross-sectional study analyzed postmenopausal patients. We included only patients with panoramic radiographs with good quality and who underwent osteoporosis risk assessment by dual-energy x-ray absorptiometry (DXA).

INDEPENDENT VARIABLE

BMD was measured by DXA at 3 sites (spine, femur, and forearm) and used to classify the patients into normal, osteopenic, or osteoporotic. This classification remained consistent across all measurement sites.

MAIN OUTCOME VARIABLE

The main outcome variable was BMD of the mandibular canal cortices measured using black pixel intensity.

COVARIATES

Demographic covariates, including age, weight, height, and BMD, were assessed.

ANALYSES

One-way analysis of variance between groups considering a P < .05. The relationship between covariates and dependent variables was assessed using the Pearson correlation test.

RESULTS

The sample comprised 52 postmenopausal women aged more than 40 years (mean age 61 ± 10 years), 26 (50%) normal, 18 (35%) osteopenic, and 8 (15%) osteoporotic. Significant differences were observed in the percentage of black pixels in the mandibular ramus between the groups. In this region, the average percentage of black pixels was 3.19% (± 0.65) for the normal group, 2.78% (± 0.65) for the osteopenia group, and 2.35% (± 0.65) for the osteoporosis group (P = .015). No significant differences were found in other mandibular regions.

CONCLUSION AND RELEVANCE

Our findings demonstrate an association between BMD assessed in the mandibular canal cortex and the presence of osteoporosis as determined by DXA. While the observed differences in black pixel percentages in the mandibular ramus are minor, they are statistically significant, suggesting that panoramic radiography may serve as an adjunctive tool for osteoporosis screening.

Using advanced imaging to measure bone density, compression fracture risk, and risk for construct failure after spine surgery

Low bone mineral density (BMD) can predispose to vertebral body compression fractures and postoperative instrumentation failure. DEXA is considered the gold standard for measurement of BMD, however it is not obtained for all spine surgery patients preoperatively. There is a growing body of evidence suggesting that more routinely acquired spine imaging studies such as computed tomography (CT) and magnetic resonance imaging (MRI) can be opportunistically used to measure BMD. Here we review available studies that assess the validity of opportunistic screening with CT-derived Hounsfield Units (HU) and MRI-derived vertebral vone quality (VBQ) to measure BMD of the spine as well the utility of these measures in predicting postoperative outcomes. Additionally, we provide screening thresholds based on HU and VBQ for prediction of osteopenia/ osteoporosis and postoperative outcomes such as cage subsidence, screw loosening, proximal junctional kyphosis, and implant failure.

Unveiling novel metabolic alterations in postmenopausal osteoporosis and type 2 diabetes mellitus through NMR-based metabolomics: A pioneering approach for identifying early diagnostic markers

BACKGROUND AND AIMS

Postmenopausal osteoporosis (PMO) and type 2 diabetes mellitus (T2DM) frequently coexist in postmenopausal women. The study aimed to explore metabolic variations linked to these circumstances and their simultaneous presence through proton nuclear magnetic resonance metabolomics (1H NMR).

MATERIALS AND METHODS

Serum samples from 80 postmenopausal women, including 20 PMO individuals, 20 T2DM, 20 T2DM + PMO, and 20 healthy postmenopausal women, were analyzed using 1H NMR spectroscopy.

RESULTS

Our study revealed significant metabolic profile differences among the four groups. Notably, the T2DM + PMO group showed elevated levels of alanine, pyruvate, glutamate, lactate, and aspartate, indicating their involvement in lipid metabolism, energy, and amino acids. Importantly, our multivariate statistical analysis identified a metabolite set that accurately distinguished the groups, suggesting its potential as an early diagnostic marker.

CONCLUSION

The 1H NMR metabolomics approach uncovered metabolic biomarkers intricately linked to postmenopausal osteoporosis (PMO), type 2 diabetes mellitus (T2DM), and their concurrent presence. Among these biomarkers, alanine emerged as a pivotal player, showing its significant role in the metabolic landscape associated with PMO and T2DM. These findings shed light on the pathophysiological mechanisms underlying these conditions and underscore alanine's potential as a diagnostic biomarker.

Femora of women with premature ovarian insufficiency exhibit reduced strength and misalignment with the transmitted vertical forces from the upper body

BACKGROUND

Women with premature ovarian insufficiency (POI) lack oestrogen, which is a key determinant of bone growth, epiphyseal closure, and bone tissue organisation. Although dual-energy X-ray absorptiometry (DXA)-derived areal bone mineral density (BMD) remains the gold standard for fracture risk evaluation, it does not fully characterise the skeletal abnormalities present in these women. Hence, we aimed to assess hip/femur anatomy, strength, and geometry and femoral alignment using advanced hip analysis (AHA).

METHODS

We conducted a cross-sectional, case-control study including 89 women with spontaneous normal karyotype POI (s-POI) or iatrogenic POI (i-POI), aged 20-50 years compared with 89 age- and body mass index (BMI)-matched population-based female controls. Hip anatomy, strength, geometrical parameters, and femur alignment were measured using hip DXA images and Lunar AHA software. Femoral orientation angle (FOA) was quantified as the overall orientation of the femur with respect to the axis of the forces transmitted from the upper body.

RESULTS

The median age of POI diagnosis was 35 (18-40) years; the mean POI duration at the time of DXA was 2.07 (range 0-13) years, and 84% of POI women received oestrogen therapy. Areal BMD at all sites was significantly lower in the POI group (all P < .05). Indices of compressive and bending strength were lower in women with POI compared with controls, specifically the cross-sectional area (CSA, mm2) and section modulus (SM, mm3) (139.30 ± 29.08 vs 157.29 ± 22.26, P < .001 and 665.21 ± 129.54 vs 575.53 ± 150.88, P < .001, respectively). The FOA was smaller (124.99 ± 3.18) in women with POI as compared with controls (128.04 ± 3.80; P < .001) at baseline and after adjusting for height and femoral neck BMD.

CONCLUSION

Alongside lower BMD at multiple sites, the femora of women with POI demonstrate reduced strength and a misalignment with forces transmitted from the upper body. Further research is needed to establish the role of these newly identified features and their role in fracture risk prediction in this population.

Bone Remodeling and Modeling: Cellular Targets for Antiresorptive and Anabolic Treatments, Including Approaches Through the Parathyroid Hormone (PTH)/PTH-Related Protein Pathway

Bone is continuously in a state of building and renewal, though the process of remodeling that takes place at many sites asynchronously throughout the skeleton, with bone formation and resorption equal at these sites (bone multicellular units). Remodeling takes place on bone surfaces, both on trabeculae and in the cortex, and serves the purposes of replacing old bone or that damaged by microfractures throughout the skeleton. The bone loss and consequent osteoporotic fractures that result from excess resorption over formation have mainly been prevented or treated by antiresorptive drugs that inhibit osteoclast formation and/or activity. Virtually all of the evidence leading to acceptance of antiresorptive drugs as treatment has depended upon their prevention of vertebral fractures. In recent decades, new prospects came of anabolic treatments that partly restore bone volume and microstructure restore bone that has been lost. The first of these was parathyroid hormone (PTH), shown by daily injection to increase markers of bone formation and prevent fractures. This field of interest enlarged with the discovery of PTH-related protein (PTHrP), so closely related in structure and action to PTH. The structural relationship between PTH and PTHrP is important in assessing their physiological and pharmacological roles, with the N-terminal domains of the 2 having virtually equal actions on target cells. Abaloparatide, a peptide analogue based on the structures of PTHrP and PTH, has been approved in some countries as a therapy for osteoporosis. Treatment through the PTH receptor activation pathway, and probably with any anabolic therapy, needs to be followed by antiresorptive treatment in order to maintain bone that has been restored. No matter how effective anabolic therapies for the skeleton become, it seems highly likely that there will be a continuing need for antiresorptive drugs.

The Fracture Risk Assessment Tool Probability and Trabecular Bone Score Mediate the Relationship between Sphingosine 1-phosphate Levels and Fracture Risk

BACKGROUND

The sphingosine 1-phosphate (S1P) concentration is a potential biomarker of osteoporotic fracture and is associated with both the fracture risk assessment tool (FRAX) probability and trabecular bone score (TBS), which are well-known predictors of fracture. We sought to estimate the effect of the S1P concentration on fracture risk using the FRAX probability and TBS as mediators.

METHODS

Plasma S1P concentrations, FRAX variables, and TBSs were measured in 66 postmenopausal women with fractures and 273 postmenopausal women without fractures. Associations between S1P concentration, FRAX probability, TBS, and fracture risk were analyzed using correlation, logistic regression, and mediation analyses.

RESULTS

Subjects in the highest S1P concentration tertile had a higher fracture risk (odds ratio [OR], 5.09; 95% confidence interval [CI], 2.22-11.67) than those in the lowest S1P concentration tertile before adjustment. Subjects in the highest FRAX probability tertile had a higher fracture risk (OR, 14.59; 95% CI, 5.01-42.53) than those in the lowest FRAX probability tertile before adjustment. Subjects in the lowest TBS tertile had a higher fracture risk (OR, 4.76; 95% CI, 2.28-9.93) than those in the highest TBS tertile before adjustment. After adjustment for FRAX probability and TBS, the highest S1P concentration tertile was still associated with a higher fracture risk (OR, 3.13; 95% CI, 1.28-7.66). The FRAX probability and TBS accounted for 32.6% and 21.7%, respectively, of the relationship between the S1P concentration and fracture risk.

CONCLUSIONS

The relationship between the circulating S1P concentration and fracture risk was partly mediated by the FRAX probability, bone microarchitecture, and other factors.

Machine Learning for Opportunistic Screening for Osteoporosis and Osteopenia Using Knee CT Scans

PURPOSE

To predict whether a patient has osteoporosis/osteopenia using the attenuation of trabecular bone obtained from knee computed tomography (CT) scans.

METHODS

Retrospective analysis of 273 patients who underwent contemporaneous knee CT scans and dual-energy X-ray absorptiometry (DXA) within 1 year. Volumetric segmentation of the trabecular bone of the distal femur, proximal tibia, patella, and proximal fibula was performed to obtain the bone CT attenuation. The data was randomly split into training/validation (78%) and test (22%) datasets and the performance in the test dataset were evaluated. The predictive properties of the CT attenuation of each bone to predict osteoporosis/osteopenia were assessed. Multivariable support vector machines (SVM) and random forest classifiers (RF) were used to predict osteoporosis/osteopenia.

RESULTS

Patients with a mean age (range) of 67.9 (50-87) years, 85% female were evaluated. Seventy-seven (28.2%) of patients had normal bone mineral density (BMD), 140 (51.3%) had osteopenia, and 56 (20.5%) had osteoporosis. The proximal tibia had the best predictive ability of all bones and a CT attenuation threshold of 96.0 Hounsfield Units (HU) had a sensitivity of .791, specificity of .706, and area under the curve (AUC) of .748. The AUC for the SVM with cubic kernel classifier (AUC = .912) was better than the RF classifier (AUC = .683, P < .001) and better than using the CT attenuation threshold of 96.0 HU at the proximal tibia (AUC = .748, P = .025).

CONCLUSIONS

Opportunistic screening for osteoporosis/osteopenia can be performed using knee CT scans. Multivariable machine learning models are more predictive than the CT attenuation of a single bone.

Update on the clinical use of trabecular bone score (TBS) in the management of osteoporosis: results of an expert group meeting organized by the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO), and the International Osteoporosis Foundation (IOF) under the auspices of WHO Collaborating Center for Epidemiology of Musculoskeletal Health and Aging

PURPOSE

Trabecular bone score (TBS) is a grey-level textural measurement acquired from dual-energy X-ray absorptiometry lumbar spine images and is a validated index of bone microarchitecture. In 2015, a Working Group of the European Society on Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO) published a review of the TBS literature, concluding that TBS predicts hip and major osteoporotic fracture, at least partly independent of bone mineral density (BMD) and clinical risk factors. It was also concluded that TBS is potentially amenable to change as a result of pharmacological therapy. Further evidence on the utility of TBS has since accumulated in both primary and secondary osteoporosis, and the introduction of FRAX and BMD T-score adjustment for TBS has accelerated adoption. This position paper therefore presents a review of the updated scientific literature and provides expert consensus statements and corresponding operational guidelines for the use of TBS.

METHODS

An Expert Working Group was convened by the ESCEO and a systematic review of the evidence undertaken, with defined search strategies for four key topics with respect to the potential use of TBS: (1) fracture prediction in men and women; (2) initiating and monitoring treatment in postmenopausal osteoporosis; (3) fracture prediction in secondary osteoporosis; and (4) treatment monitoring in secondary osteoporosis. Statements to guide the clinical use of TBS were derived from the review and graded by consensus using the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach.

RESULTS

A total of 96 articles were reviewed and included data on the use of TBS for fracture prediction in men and women, from over 20 countries. The updated evidence shows that TBS enhances fracture risk prediction in both primary and secondary osteoporosis, and can, when taken with BMD and clinical risk factors, inform treatment initiation and the choice of antiosteoporosis treatment. Evidence also indicates that TBS provides useful adjunctive information in monitoring treatment with long-term denosumab and anabolic agents. All expert consensus statements were voted as strongly recommended.

CONCLUSION

The addition of TBS assessment to FRAX and/or BMD enhances fracture risk prediction in primary and secondary osteoporosis, adding useful information for treatment decision-making and monitoring. The expert consensus statements provided in this paper can be used to guide the integration of TBS in clinical practice for the assessment and management of osteoporosis. An example of an operational approach is provided in the appendix. This position paper presents an up-to-date review of the evidence base, synthesised through expert consensus statements, which informs the implementation of Trabecular Bone Score in clinical practice.

Age-Related Factors Associated With The Risk of Hip Fracture

OBJECTIVE

Advancing age is a powerful risk factor for hip fractures. The biological mechanisms through which aging impacts the risk of hip fractures have not been well studied.

METHODS

Biological factors associated with "advancing age" that help to explain how aging is associated with the risk of hip fractures are reviewed. The findings are based on analyses of the Cardiovascular Health Study, an ongoing observational study of adults aged ≥65 years with 25 years of follow-up.

RESULTS

The following 5 age-related factors were found to be significantly associated with the risk of hip fractures: (1) microvascular disease of the kidneys (albuminuria and/or elevated urine-albumin-to-creatinine ratio) and brain (abnormal white matter disease on brain magnetic resonance imaging); (2) increased serum levels of carboxymethyl-lysine, an advanced glycation end product that reflects glycation and oxidative stress; (3) reduced parasympathetic tone, as derived from 24-hour Holter monitoring; (4) carotid artery atherosclerosis in the absence of clinical cardiovascular disease; and (5) increased transfatty acid levels in the blood. Each of these factors was associated with a 10% to 25% increased risk of fractures. These associations were independent of traditional risk factors for hip fractures.

CONCLUSION

Several factors associated with older age help to explain how "aging" may be associated with the risk of hip fractures. These same factors may also explain the high risk of mortality following hip fractures.

Behavior during aging of bone-marrow fatty-acids profile in women's calcaneus to search for early potential osteoporotic biomarkers: a 1H-MR Spectroscopy study

AIM

Identify new potential biomarkers of osteoporosis at an early stage, by magnetic resonance spectroscopy (MRS), studying early changes in the metabolic profile of bone-marrow fatty acids in women's calcanei during healthy aging and osteoporosis status.

METHODS

Single voxel MRS was performed by using a point resolved spectroscopy (PRESS) sequence at 3T. Thirty-four Caucasian women (age range: 22-59 years) were recruited to investigate calcaneus bone marrow. The cohort was constituted of four groups according to age, menopausal status, and T-score evaluated after a DXA examination on the femoral neck. Women were classified in young control (n = 11, mean age = 26.5 ± 3.8 y, age range: 22-34 years), perimenopausal groups (n = 11, mean age = 42.0 ± 3.6 y, age range: 37-47 years), postmenopausal group (n = 9, mean age = 55.4 ± 2.9 y, age range: 50-59 years, mean T-score = -1.70 ± 0.50) and osteoporotic group (n = 6, mean age = 53.0 ± 2.8 y, age range: 50-58 years, mean T-score = -2.54 ± 0.10). The total lipid content (TL), the Unsaturation Index (UI), and the fraction of unsaturated/polyunsaturated fatty acid (f_UFA and f_PUFA) were calculated.

RESULTS

TL was significantly correlated with age (r = 0.73, p < 0.001). TL increases linearly with age in the young + perimenopausal population (r = 0.92, p < 0.001) but this trend is not significant in the postmenopausal subject (r = 0.48, p = 0.07). No significant correlation was found between T-Score and TL in postmenopausal and osteoporotic women, whereas a significant correlation was found between TL and time interval (t_p) between the age at menopause and the age of the subject at the MRS examination. Conversely, no correlation was found between T-score and t_p. The unsaturation index (UI) does not significantly discriminate between osteoporotic, peri- and postmenopausal women. On the other hand, f_UFA is significantly different in peri-menopausal and osteoporotic subjects (p = 0.02), while f_PUFA is significantly different both between peri- and postmenopausal women (p = 0.05) and postmenopausal and osteoporotic subjects (p = 0.03). Both f_UFA and f_PUFA did not correlate with subjects' age.

CONCLUSION

In the female calcaneus, f_UFA and f_PUFA are promising measurable quantities for the characterization of bone marrow's composition potentially correlated with the development of osteoporosis, whereas UI does not differentiate between subjects of varying osteoporotic status. The fact that the TL in the calcaneus is correlated with t_p, indicates that active metabolic changes are still occurring in these subjects, giving complementary information to the DXA about the changes in bone marrow's composition which may affect the whole bone health.

Features of mandibular cortical bone morphology in osteoporotic fracture patients

PURPOSE

The diagnostic criteria for osteoporosis are based on the bone mineral density (BMD) level in the lumbar spine and femur bone. Patients with osteoporotic fractures were diagnosed with osteoporosis. While systemic BMD and mandibular cortical bone morphology are correlated, this has not been studied in patients with a history of osteoporotic fractures. Therefore, purpose of this study was researching the mandibular cortical bone morphology in patients with osteoporotic fractures.

METHODS

The subjects were 55 female and 20 male patients with osteoporotic fractures. Patients were divided into 30 primary osteoporosis patients and 45 secondary osteoporosis patients according to the medical history. Patients underwent BMD and panoramic radiography examinations during orthopedic treatment for fractures. A dual-energy X-ray absorptiometry system was used to measure BMD. Mandibular cortex index (MCI) and mandibular cortex width (MCW) were evaluated using machine-learning measurement software.

RESULTS

In the analysis of MCI, the ratio of class 2 and 3 was 73% of both primary osteoporosis and secondary osteoporosis. The average MCW was 2.19 mm for primary osteoporosis and 2.30 mm for secondary osteoporosis. The sensitivity values by MCI and MCW were 73% and 76% for both primary and secondary osteoporosis, which were similar detection powers. In addition, the false-negative rates by MCI and MCW were 27% and 24%.

CONCLUSION

We suggested that MCI and MCW are indicators of osteoporotic conditions in patients with primary and secondary osteoporosis. Our results show that MCI and MCW are non-inferior to the sensitivity values for lumbar BMD in patients with osteoporotic fractures.

Trabecular bone score as an additional therapeutic decision tool in osteoporosis and osteopenia

Objectives

To evaluate the role of trabecular bone score (TBS), in addition to bone mineral density (BMD), and to aid decision making to initiate anti-osteoporotic treatment in postmenopausal women with osteopenia.

Methods

TBS was assessed in a cohort of Thai postmenopausal women with BMD of femoral neck (FN), total hip (TH), and lumbar spine (LS) performed at the Police General Hospital, Bangkok, Thailand from July 2019 to October 2020. We retrospectively reviewed hospital database for underlying diseases, medication, and fractures, including relevant imaging and vertebral fracture assessment (VFA). Patients with previous osteoporosis treatment, skeletal malignancy, high-energy trauma, and uninterpretable BMD were excluded.

Results

In total there were 407 postmenopausal women, including 115 with osteoporotic fractures. The mean TBS of the cohort was 1.264 ± 0.005. The proportion of osteoporotic subjects ranged from 9.1% by TH BMD to 27.0% by lowest BMD. In fractured patients, 21.7%–54.8% were found to have osteoporosis while osteopenia was found in 37.4%–43.5%. Among subjects with osteopenia and degraded TBS, fractures ranged from 21.7 to 50.9%. Addition of osteopenic subjects with degraded microarchitecture yielded a significantly higher number of subjects eligible for treatment with 3.25-fold increase in non-fractured participants, and 7 to 11 additional osteopenic patients should be treated to detect 1 fracture.

Conclusions

Addition of TBS helped capturing osteopenic women with high risk of fracture. Decision to treat osteopenic women with degraded TBS increased the number of patients receiving treatment. We recommend evaluating TBS in osteopenic women without fractures to aid therapeutic decision on treatment initiation.

Fracture Risk Assessment: An Update

➤

Our ability to accurately identify high fracture risk in individuals has improved as the volume of clinical data has expanded and fracture risk assessment tools have been developed.

➤

Given its accessibility, affordability, and low radiation exposure, dual x-ray absorptiometry (DXA) remains the standard for osteoporosis screening and monitoring response to treatment.

➤

The trabecular bone score (TBS) is a DXA software add-on that uses lumbar spine DXA imaging to produce an output that correlates with bone microarchitecture. It has been identified as an independent fracture risk factor and may prove useful in further stratifying fracture risk among those with a bone mineral density (BMD) in the osteopenic range (-1.0 to -2.4 standard deviations), in those with low-energy fractures but normal or only mildly low BMD, or in those with conditions known to impair bone microarchitecture.

➤

Fracture risk assessment tools, including the Fracture Risk Assessment Tool (FRAX), Garvan fracture risk calculator, and QFracture, evaluate the impact of multiple clinical factors on fracture risk, even in the absence of BMD data. Each produces an absolute fracture risk output over a defined interval of time. When used appropriately, these enhance our ability to identify high-risk patients and allow us to differentiate fracture risk among patients who present with similar BMDs.

➤

For challenging clinical cases, a combined approach is likely to improve accuracy in the identification of high-risk patients who would benefit from the available osteoporosis therapies.

Associations of Circulating Levels of Sphingosine 1-Phosphate with the Trabecular Bone Score and Bone Mineral Density in Postmenopausal Women

Despite the potential roles of sphingosine 1-phosphate (S1P) as a biomarker of osteoporotic fracture (OF), independent of bone mineral density (BMD) and clinical risk factors (CRFs), its association with bone microarchitecture, a key determinant of bone quality, have not been studied yet. We here investigated the association of S1P with the trabecular bone score (TBS), an index of the bone microarchitecture. The plasma S1P concentrations, TBS, and BMD were measured in the 339 postmenopausal women. The S1P level was inversely correlated with the TBS (γ=-0.096, p=0.049) and BMD at the femur neck (FN-BMD: γ=-0.122, p=0.025) and tended to be inversely correlated the BMD at the total hip (TH-BMD: γ=-0.096, p=0.079), but not at the lumbar spine (LS-BMD). After adjusting for fracture risk assessment tool probabilities of major OF from CRFs, the S1P level was inversely associated with the TBS (β=-0.096, p=0.049) and FN-BMD (β=-0.118, p=0.025) and tended to be inversely associated with the TH-BMD (β=-0.092, p=0.083). Compared with subjects in the lowest S1P tertile, those in the highest S1P tertile had a significantly lower TBS (p=0.032) and BMD at femur (p=0.004-0.036). These findings indicated that a high S1P level in postmenopausal women was inversely associated with the both bone mass and microarchitecture, reflecting the compromised bone strength.

High-Resolution Cone-Beam Computed Tomography is a Fast and Promising Technique to Quantify Bone Microstructure and Mechanics of the Distal Radius

Obtaining high-resolution scans of bones and joints for clinical applications is challenging. HR-pQCT is considered the best technology to acquire high-resolution images of the peripheral skeleton in vivo, but a breakthrough for widespread clinical applications is still lacking. Recently, we showed on trapezia that CBCT is a promising alternative providing a larger FOV at a shorter scanning time. The goals of this study were to evaluate the accuracy of CBCT in quantifying trabecular bone microstructural and predicted mechanical parameters of the distal radius, the most often investigated skeletal site with HR-pQCT, and to compare it with HR-pQCT. Nineteen radii were scanned with four scanners: (1) HR-pQCT (XtremeCT, Scanco Medical AG, @ (voxel size) 82 μm), (2) HR-pQCT (XtremeCT-II, Scanco, @60.7 μm), (3) CBCT (NewTom 5G, Cefla, @75 μm) reconstructed and segmented using in-house developed software and (4) microCT (VivaCT40, Scanco, @19 μm-gold standard). The following parameters were evaluated: predicted stiffness, strength, bone volume fraction (BV/TV) and trabecular thickness (Tb.Th), separation (Tb.Sp) and number (Tb.N). The overall accuracy of CBCT with in-house optimized algorithms in quantifying bone microstructural parameters was comparable (R² = 0.79) to XtremeCT (R² = 0.76) and slightly worse than XtremeCT-II (R² = 0.86) which were both processed with the standard manufacturer's technique. CBCT had higher accuracy for BV/TV and Tb.Th but lower for Tb.Sp and Tb.N compared to XtremeCT. Regarding the mechanical parameters, all scanners had high accuracy (R² [Formula: see text] 0.96). While HR-pQCT is optimized for research, the fast scanning time and good accuracy renders CBCT a promising technique for high-resolution clinical scanning.

Severe osteoporosis: Principles for pharmacological therapy in Mexico

BACKGROUND

This article presents evidence and recommendations regarding the efficacy and safety of the approved and available therapies in Mexico to treat severe or established osteoporosis with the aim of developing a position regarding therapeutics in this stage of the disease, according to the descriptive cards of the National Drug Formulary of the National General Health Council of Mexico.

METHODS

We performed a systematic and narrative review of the evidence of teriparatide and denosumab, from their pharmacological profile, effectiveness, and safety derived from clinical trials, as well as an analysis of the general recommendations of the national and international clinical practice guidelines.

RESULTS

The evidence establishes that teriparatide and denosumab belong to different therapeutic classes, with biologically opposed mechanisms of action and indications of use, which are clearly differentiated in their respective national codes, therefore these drugs cannot be substitutable or interchangeable in severe osteoporosis therapy. Both represent the best options currently available for this stage of the disease; being similar in their efficacy in preventing new vertebral fragility fractures, with an RR of .35 (CI 95%; .22-.55) for teriparatide, and .32 (CI 95%: .26-.41) for denosumab. The absolute risk reduction is higher with teriparatide 9.3% (21 months) compared with denosumab at 4.8% (36 months).

CONCLUSIONS

Our results agree with the recommendations available in national and international clinical practice guidelines, with both therapies proposed as a sequential, but not a substitute, treatment.

Development of a QUS Device to Evaluate Deterioration of Cortical Bone: Verification by HR-pQCT and Measurements in Healthy Individuals and Dialysis Patients

INTRODUCTION

The objectives of this study were to identify what is reflected in cortical speed of sound (cSOS) measured by a cortical quantitative ultrasound (cortical QUS) device we have developed, and to investigate cSOS measurements in healthy individuals and dialysis patients.

METHODS

The cSOS and the SOS were measured by cortical QUS and conventional QUS in 20 volunteers, and the correlations between these measurements and areal bone mineral density measured by dual-energy X-ray absorptiometry and bone microstructural parameters on high-resolution peripheral quantitative computed tomography were analyzed. The cSOS and the SOS were measured in 91 young adults (47 men, 44 women), 64 elderly people (30 men, 33 women), and 64 dialysis patients (33 men, 31 women). The period of hemodialysis and intact parathyroid hormoneevels were also investigated in the dialysis patients.

RESULTS

cSOS was correlated with cortical tissue mineral density (tibia: r = 0.74, radius: r = 0.72) on high-resolution peripheral quantitative computed tomography, reflecting the degree of minaralization and microporosity of cortical bone. There was no correlation with the thickness of cortical bone, suggesting that it measured the bone quality rather than bone mass. Elderly women had lower cSOS than young adults (3865 ± 74 vs 3971 ± 63 m/s, p < 0.01). Many of dialysis patients showed very low cSOS and it was related to higher intact parathyroid hormone levels (male: ß = -0.67, female: ß = -0.60).

CONCLUSIONS

Our cortical QUS device is capable of evaluating the qualitative degradation of cortical bone, which cannot be assessed by conventional QUS, and its use in combination with conventional QUS may provide a better understanding of fracture risk.

Ten-year fracture risk predicted by proximal femur Hounsfield units

Colon cancer screening occurs at younger ages than osteoporosis screening. Bone density measurements using virtual colonoscopy performed for colon cancer screening can provide an early warning sign of patients at potential risk for osteoporosis-related fractures. Earlier identification may improve treatment and potentially fracture prevention.

INTRODUCTION

Opportunistic osteoporosis screening with computed tomography colonography (CTC) offers an opportunity to capitalize on earlier colorectal cancer screening to identify patients at risk of future fractures. The purpose of this study is to evaluate 10-year fracture and specifically hip fracture risk based on Hounsfield units (HU) obtained from CTC.

METHODS

We identified all CTC scans between 2004 and 2007 of patients 40 years and older with 10 years minimum follow-up. Hounsfield units were measured within the proximal femur and fractures identified via worldwide military records. Patients were stratified into two cohorts based on the presence or lack of a fracture in the wrist, spine, hip, or proximal humerus. Hounsfield unit measurements were compared between groups using Student's t test and the HU threshold was calculated that best approximated an 80% sensitivity to optimally screen patients for fracture risk. The odds ratio, negative predictive value, 10-year incidence of fracture, and survival curves were calculated.

RESULTS

We identified 3711 patients with 183 fractures over 10 years. The HU threshold that corresponded with an 80% sensitivity to identify fractures was 112 HU. The negative predictive value (NPV) for overall fractures and hip fractures was over 97%. The 10-year fracture incidence was higher in patients below 112 HU compared to those above for both overall fractures (6.3% vs 1.7%) and hip fractures (2.7% vs 0.07%). The 112 HU threshold corresponds with an odds ratio for overall fracture and hip fractures of 2.5 (95% confidence interval (CI), 1.7-3.6) and 24.5 (95% CI, 3.3-175.5), respectively.

CONCLUSION

In the 10 years following CTC, patients who experienced a fracture had lower hip HU. Decreasing HU on CTC may be an early warning sign of fracture potential.

Nanoscale mechanisms in age-related hip-fractures

Nanoscale mineralized collagen fibrils may be important determinants of whole-bone mechanical properties and contribute to the risk of age-related fractures. In a cross-sectional study nano- and tissue-level mechanics were compared across trabecular sections from the proximal femora of three groups (n = 10 each): ageing non-fractured donors (Controls); untreated fracture patients (Fx-Untreated); bisphosphonate-treated fracture patients (Fx-BisTreated). Collagen fibril, mineral and tissue mechanics were measured using synchrotron X-Ray diffraction of bone sections under load. Mechanical data were compared across groups, and tissue-level data were regressed against nano. Compared to controls fracture patients exhibited significantly lower critical tissue strain, max strain and normalized strength, with lower peak fibril and mineral strain. Bisphosphonate-treated exhibited the lowest properties. In all three groups, peak mineral strain coincided with maximum tissue strength (i.e. ultimate stress), whilst peak fibril strain occurred afterwards (i.e. higher tissue strain). Tissue strain and strength were positively and strongly correlated with peak fibril and mineral strains. Age-related fractures were associated with lower peak fibril and mineral strain irrespective of treatment. Indicating earlier mineral disengagement and the subsequent onset of fibril sliding is one of the key mechanisms leading to fracture. Treatments for fragility should target collagen-mineral interactions to restore nano-scale strain to that of healthy bone.

Identification of patients at high risk of fragility fractures in an Indian clinical setting using FRAX

A case-control study was done to decipher whether the FRAX tool was useful in India. Several values around the mean and median of the FRAX score of the case group were assessed to calculate sensitivity, specificity, positive predictive value, negative predictive value, Youden's index and odds ratio, and to detect high-risk individuals.

PURPOSE

The Fracture Risk Assessment Tool (FRAX) appears useful to diagnose fragility fractures. The study aims to answer whether the FRAX tool has utility in India.

METHODS

One hundred ten cases with a history of recent fragility fractures and 84 controls with no fractures were included in the study. FRAX scores without bone mineral density (BMD), and also with it, of participants were calculated. Several cutoff FRAX scores were chosen around mean and median FRAX score of cases. The odds ratio was calculated along with sensitivity, specificity, positive predictive value, negative predictive value and Youden's index. The most ideal cutoff was chosen to construct a hypothetical model to detect individuals at high risk.

RESULTS

The FRAX score with BMD and without BMD exhibited relatively high specificity and moderate to low sensitivity implying that FRAX scores above cutoff have diagnostic value. Cutoffs at which FRAX score without BMD exhibited high specificity (> 90%) were chosen to construct a hypothetical model. Patients with FRAX score without BMD in the intermediate range be advised dual-energy X-ray absorptiometry (DEXA) followed by recalculation of FRAX score with BMD. DEXA scan T score less than - 2.5 or FRAX score with BMD above the cutoff at which specificity was high (> 80%) were included to construct the hypothetical model. Patients with low FRAX score could be followed up. The hypothetical model was applied to the case group to analyse its detection potential.

CONCLUSION

FRAX has utility in India. It cuts the cost of screening and limits the use of expensive investigation.

Deterioration of Cortical and Trabecular Microstructure Identifies Women With Osteopenia or Normal Bone Mineral Density at Imminent and Long-Term Risk for Fragility Fracture: A Prospective Study

More than 70% of women sustaining fractures have osteopenia or "normal" bone mineral density (BMD). These women remain undetected using the BMD threshold of -2.5 SD for osteoporosis. As microstructural deterioration increases bone fragility disproportionate to the bone loss producing osteopenia/normal BMD, we hypothesized that the structural fragility score (SFS) of ≥70 units, a measure capturing severe cortical and trabecular deterioration, will identify these women. Distal radial images were acquired using high-resolution peripheral quantitative tomography in postmenopausal French women, mean age 67 years (range 42-96 years); 1539 women were followed for 4 years (QUALYOR) and 561 women followed for 8 years (OFELY). Women with osteopenia or normal BMD accounted for ~80% of fractures. Women ≥70 years, 29.2% of the cohort, accounted for 39.2% to 61.5% of fractures depending on follow-up duration. Women having fractures had a higher SFS, lower BMD, and a higher fracture risk assessment score (FRAX) than women remaining fracture-free. In each BMD category (osteoporosis, osteopenia, normal BMD), fracture incidence was two to three times higher in women with SFS ≥70 than <70. In multivariable analyses, associations with fractures remained for BMD and SFS, not FRAX. BMD was no longer, or weakly, associated with fractures after accounting for SFS, whereas SFS remained associated with fracture after accounting for BMD. SFS detected two-to threefold more women having fractures than BMD or FRAX. SFS in women with osteopenia/normal BMD conferred an odds ratio for fracture of 2.69 to 5.19 for women of any age and 4.98 to 12.2 for women ≥70 years. Receiver-operator curve (ROC) analyses showed a significant area under the curve (AUC) for SFS, but not BMD or FRAX for the women ≥70 years of age. Targeting women aged ≥70 years with osteopenia indicated that treating 25% using SFS to allocate treatment conferred a cost-effectiveness ratio < USD $21,000/QALY saved. Quantifying microstructural deterioration complements BMD by identifying women without osteoporosis at imminent and longer-term fracture risk. © 2019 American Society for Bone and Mineral Research.

Radiofrequency echographic multi spectrometry for the prediction of incident fragility fractures: A 5-year follow-up study

PURPOSE

To investigate the effectiveness of the T-score values provided by Radiofrequency Echographic Multi Spectrometry (REMS) in the identification of patients at risk for incident osteoporotic fractures.

METHODS

A population of Caucasian women (30-90 years), enrolled from 2013 to 2016, underwent dual X-ray absorptiometry (DXA) and REMS scans at axial sites. The incidence of fragility fractures was assessed during a follow-up period up to 5 years. Afterwards, patients with and without incident fractures were stratified in two age-matched groups with a 1: 2 proportion (Group F' and Group NF', respectively). The performance of REMS T-score in discriminating between the two groups was quantitatively assessed and compared with DXA.

RESULTS

1516 patients were enrolled and 1370 completed the follow-up (mean ± SD: 3.7 ± 0.8 years; range: 1.9-5.0 years). Fracture incidence was 14.0%. Age-matched groups included 175 fractured patients and 350 non-fractured ones, respectively (median age 70.2 [interquartile range: 61.0-73.3] and 67.3 [65.4-69.8] years, p-value ns). The groups resulted also balanced for height, weight and BMI (p-values ns). As expected, the differences in REMS T-score (for vertebral site, -2.9 [-3.6 to -1.9] in Group F', -2.2 [-2.9 to -1.2] in Group NF') and DXA T-score (-2.8 [-3.3 to -1.9] in Group F', -2.2 [-2.9 to -1.4] in Group NF') were statistically significant (p-value <0.001). Analogous results were obtained for femoral neck. Considering the T-score cut-off of -2.5, REMS identified Group F' patients with a sensitivity of 65.1% and specificity of 57.7% of (OR = 2.6, 95%CI: 1.77-3.76, p < 0.001), whereas DXA showed a sensitivity of 57.1% and a specificity of 56.3% (OR = 1.7, 95%CI: 1.20-2.51, p-value = 0.0032). For femoral neck, REMS sensitivity and specificity were 40.2% and 79.9%, respectively, with an OR of 2.81 (95%CI: 1.80-4.39, p < 0.001). DXA, instead, showed a sensitivity and specificity of 42.3% and 79.3%, respectively, with an OR of 2.68 (95%CI: 1.71-4.21, p < 0.001).

CONCLUSIONS

REMS T-score resulted an effective predictor for the risk of incident fragility fractures in a population-based sample of female subjects, representing a promising parameter to enhance osteoporosis diagnosis in the clinical routine.

Differential association of dietary fat intake with DXA-based estimates of bone strength according to sex in the KNHANES IV population

The higher the dietary fat intake is in men, the worse their bone strength. By contrast, in women, both low and high fat intakes have negative impacts on bone strength. Dietary fat intake may be a modifiable factor affecting bone health, but this needs to be reconfirmed in further studies.

PURPOSE

Despite the general belief that higher fat intake may be harmful for bone health, its impact on bone strength has not been thoroughly studied.

METHODS

We conducted a population-based cross-sectional study derived from the Korea National Health and Nutrition Examination Surveys, including 2590 participants. Composite indices of femoral neck strength, such as the compression strength index (CSI), bending strength index (BSI), and impact strength index (ISI), were generated by combining bone mineral density, weight, and height with the femoral axis length and width. Nutritional status was assessed using a 24-h dietary recall questionnaire.

RESULTS

Dietary fat intake (%: energy from fat intake/total energy intake × 100) was inversely related to CSI and ISI in men, but not in women. Men in the highest three fat intake quintiles had lower CSI, BSI, and/or ISI than those in the lowest quintile (P = 0.003-0.041). In women, compared with participants in the third fat intake quintile, those in the other four quintiles had lower CSI, BSI, and/or ISI (P = 0.004-0.049). When participants were allocated to three groups according to the dietary reference intake of fat in Koreans [low (< 15%), moderate (15-30%), or high (≥ 30%)], men with a moderate or high fat intake had significantly lower ISIs than those with a low fat intake (P = 0.045 and 0.040, respectively). By contrast, compared with women consuming a moderate amount of fat, those with a high intake had lower CSI, BSI, and ISI (P = 0.024-0.048).

CONCLUSION

Higher fat intake in men may contribute to deteriorations in bone strength. However, this finding and the observed sex differences need to be reconfirmed using established methods for assessment of dietary intake other than the 24-h dietary recall method employed in this study.

Association between metabolic profiles in urine and bone mineral density of pre- and postmenopausal Chinese women

OBJECTIVE

In the present study, we aimed to characterize the pathological development of menopausal osteoporosis, as well as to explore potential biomarkers and metabolic pathways involved in osteoporosis.

METHODS

Urine samples from 322 female participants categorized by menopause status and different bone conditions were collected and analyzed based on a gas chromatography-mass spectrometry (GC-MS) approach. Multivariate and univariate statistical analyses were carried out for urinary metabolomic profile characterization and comparison.

RESULTS

Seventeen metabolites in the low bone mineral density (BMD) groups were clearly differentiated from those in normal BMD groups. Among these 17 differentiating metabolites, taurine, β-alanine, and 5-hydroxycaproic acid were found to be potential biomarkers of osteoporosis. The taurine metabolic pathway and the β-alanine metabolic pathway were found to be related to menopause and bone loss.

CONCLUSIONS

Based on the GC-MS metabolomic platform, four typical pathological phases during the progression of postmenopausal osteoporosis were described. Several differentiating metabolites and metabolic pathways were found to be closely related to the pathology of postmenopausal osteoporosis. Our results provided a solid foundation for further studies on early diagnosis and pathomechanistic evaluation.

Effects of a 12-Month Supervised, Community-Based, Multimodal Exercise Program Followed by a 6-Month Research-to-Practice Transition on Bone Mineral Density, Trabecular Microarchitecture, and Physical Function in Older Adults: A Randomized Controlled Trial

Multicomponent exercise programs are recommended to reduce fracture risk; however, their effectiveness in real-world community settings remain uncertain. This 18-month randomized controlled trial investigated the effects of a 12-month, community-based, supervised multicomponent exercise program followed by a 6-month "research-to-practice" transition on areal bone mineral density (BMD), trabecular bone microarchitecture, functional performance, and falls in older adults at increased fracture risk. One-hundred and sixty-two adults aged ≥60 years with osteopenia or at increased falls risk were randomized to the Osteo-cise: Strong Bones for Life multicomponent exercise program (n = 81) or a control group (n = 81). Exercise consisted of progressive resistance, weight-bearing impact, and balance training (3-days/week) performed at community leisure centers. Overall 148 (91%) participants completed the trial, and mean exercise adherence was 59% after 12 months and 45% during the final 6 months. After 12 months, there were significant net beneficial effects of exercise on lumbar spine and femoral neck BMD (1.0% to 1.1%, p < 0.05), muscle strength (10% to 13%, p < 0.05), and physical function (timed stair climb 5%; four-square step test 6%; sit-to-stand 16%, p ranging <0.05 to <0.001), which persisted after the 6-month transition. There were no significant effects of the 18-month intervention on distal femur or proximal tibia trabecular bone microarchitecture or falls incidence, but per protocol analysis (≥66% exercise adherence) revealed there was a significant net benefit of exercise (mean [95% confidence interval] 2.8% [0.2, 5,4]) on proximal tibia trabecular bone volume fraction (Osteo-cise 1.5% [-1.2, 4.2]; controls -1.3% [-2.6, 0.1]) after 18 months due to changes in trabecular number (Osteo-cise 1.7% [-0.9, 4.3]; controls -1.1% [-2.4, 0.2]) but not trabecular thickness (Osteo-cise - 0.2% [-0.5, 0.2]; controls -0.2% [-0.4, 0.0]). In conclusion, this study supports the effectiveness of the Osteo-cise: Strong Bones for Life program as a real-world, pragmatic, evidence-based community exercise program to improve multiple musculoskeletal health outcomes in older adults at increased fracture risk. © 2019 American Society for Bone and Mineral Research.

Myeloid-Derived Suppressor Cells at the Intersection of Inflammaging and Bone Fragility

Age-related alteration of the immune system with aging, or immunosenescence, plays a major role in several age-associated conditions, including loss of bone integrity. Studies over the past several years have clearly established the immune system is chronically activated with advanced aging, termed inflammaging, and is characterized by elevated levels of proinflammatory cytokines in response to physiological or environmental cues that essentially result in an arrested immune system that maintains a low-level state of activation. This age-associated inflammation impacts several biological systems including the innate immune system, where aging results in a skewing of the hematopoiesis toward the myeloid lineage, including the expansion of myeloid-derived suppressor cells (MDSCs). This heterogeneous population of myeloid cells classically displays immunosuppressive capacity but they also have the ability to directly differentiate into osteoclasts. This review explores the possibility of inflammaging to be involved in reduction of bone microarchitecture and loss of bone mass/strength through the expansion of MDSCs and the osteoclastogenic capacity and activity.

How well do the FRAX (Australia) and Garvan calculators predict incident fractures? Data from the Geelong Osteoporosis Study

This study reports that both FRAX and Garvan calculators underestimated fractures in Australian men and women, particularly in those with osteopenia or osteoporosis. Major osteoporotic fractures were poorly predicted, while both calculators performed acceptably well for hip fractures.

INTRODUCTION

This study assessed the ability of the FRAX (Australia) and Garvan calculators to predict fractures in Australian women and men.

METHODS

Women (n = 809) and men (n = 821) aged 50-90 years, enrolled in the Geelong Osteoporosis Study, were included. Fracture risk was estimated using FRAX and Garvan calculators with and without femoral neck bone mineral density (BMD) (FRAX_BMD, FRAX_noBMD, Garvan_BMD, Garvan_noBMD). Incident major osteoporotic (MOF), fragility, and hip fractures over the following 10 years were verified radiologically. Differences between observed and predicted numbers of fractures were assessed using a chi-squared test. Diagnostics indexes were calculated.

RESULTS

In women, 115 MOF, 184 fragility, and 42 hip fractures occurred. For men, there were 73, 109, and 17 fractures, respectively. FRAX underestimated MOFs, regardless of sex or inclusion of BMD. FRAX accurately predicted hip fractures, except in women with BMD (20 predicted, p = 0.004). Garvan underestimated fragility fractures except in men using BMD (88 predicted, p = 0.109). Garvan accurately predicted hip fractures except for women without BMD (12 predicted, p < 0.001). Fractures were underestimated primarily in the osteopenia and osteoporosis groups; MOFs in the normal BMD group were only underestimated by FRAX_BMD and fragility fractures by Garvan_noBMD, both in men. AUROCs were not different between scores with and without BMD, except for fragility fractures predicted by Garvan in women (0.696, 95% CI 0.652-0.739 and 0.668, 0.623-0.712, respectively, p = 0.008) and men, which almost reached significance (0.683, 0.631-0.734, and 0.667, 0.615-0.719, respectively, p = 0.051). Analyses of sensitivity and specificity showed overall that MOFs and fragility fractures were poorly predicted by both FRAX and Garvan, while hip fractures were acceptably predicted.

CONCLUSIONS

Overall, the FRAX and Garvan calculators underestimated MOF and fragility fractures, particularly in individuals with osteopenia or osteoporosis. Hip fractures were predicted better by both calculators. AUROC analyses suggest that Garvan_BMD performed better than Garvan_noBMD for prediction of fragility fractures.

Case finding with GARVAN fracture risk calculator in primary prevention of fragility fractures in older people

BACKGROUND

Fracture risk calculators (FRC) with DXA can guide osteoporosis (OP) management in the absence of dual X-ray absorptiometry (DXA). There is little information of the role of FRC without DXA.

OBJECTIVES

Determine the accuracy of age-stratified Garvan FRC thresholds without DXA to manage OP.

METHODS

Cross-sectional study of 531 participants, ≥70 years old who underwent DXA and had Garvan FRC scores with and without DXA calculated. Age-stratified Garvan scores without DXA, generated low (no action), moderate (order DXA) or high (treat without DXA) risk thresholds of OP. Accuracy of our thresholds were assessed against DXA confirmed OP.

RESULTS

Age-specific GARVAN thresholds resulted in the correct decision in 85-88% of cases; "over-treated" OP in 7-8%; and, missed OP in 5-8%. 256 (48%) DXAs were unnecessary. Compared to recommended guidelines, Garvan HF and MOF thresholds improved accuracy of clinical decisions by 31% and 12%, respectively.

CONCLUSIONS

Age-specific FRC score thresholds successfully identified who required treatment or DXA, with potential to reduce unnecessary DXA.

Two-Thirds of All Fractures Are Not Attributable to Osteoporosis and Advancing Age: Implications for Fracture Prevention

CONTEXT

Although bone mineral density (BMD) is strongly associated with fracture and postfracture mortality, the burden of fractures attributable to low BMD has not been investigated.

OBJECTIVES

We sought to estimate the population attributable fraction of fractures and fracture-related mortality that can be attributed to low BMD.

DESIGN AND SETTING

This study is a part of an ongoing population-based prospective cohort study, the Dubbo Osteoporosis Epidemiology study. In total, 3700 participants aged ≥50 years participated in the study. Low-trauma fracture was ascertained by X-ray reports, and mortality was ascertained from the Birth, Death and Marriage Registry.

RESULTS

Overall, 21% of women and 11% of men had osteoporotic BMD. In univariable analysis, 21% and 16% of total fractures in women and men, respectively, were attributable to osteoporosis. Osteoporosis combined with advancing age (>70 years) accounted for 34% and 35% of fractures in women and men, respectively. However, these two factors accounted for ∼60% of hip fractures. About 99% and 66% of postfracture mortality in women and men, respectively, were attributable to advancing age, osteoporosis, and fracture; however, most of the attributable proportion was accounted for by advancing age.

CONCLUSIONS

A substantial health care burden of fracture is on people aged <70 years or nonosteoporosis, suggesting that treatment of people with osteoporosis is unlikely to reduce a large number of fractures in the general population.

Acute versus delayed reverse total shoulder arthroplasty for the treatment of proximal humeral fractures in the elderly population: a systematic review and meta-analysis

BACKGROUND

Recent literature has shown that acute reverse total shoulder arthroplasty (RTSA) yields good outcomes in the treatment of displaced proximal humeral fractures, and there have also been recent studies showing that delayed RTSA can be successfully used for sequelae of proximal humeral fractures such as nonunion and malunion. The use of meta-analysis affords the opportunity to formally compare the outcomes of acute RTSA for fracture and delayed RTSA for fracture sequelae.

METHODS

We searched the MEDLINE, Embase, and Cochrane Library databases. We included all studies reporting on RTSA for the treatment of proximal humeral fracture sequelae with a comparison group of acute RTSA or with no comparison group in adults with a mean age older than 65 years and at least 2 years of follow-up. We calculated weighted mean differences for range of motion, standardized mean differences for clinical outcome scores, and relative risks for dichotomous outcomes.

RESULTS

Sixteen studies met the inclusion criteria, which comprised 322 patients undergoing RTSA for fracture sequelae. Of these studies, 4 were comparative (46 patients) whereas 12 were case series (276 patients). Among studies directly comparing acute versus delayed RTSA, no differences in forward flexion (P = .72), clinical outcome scores (P = .78), or all-cause reoperation (P = .92) were found between the 2 groups. Patients undergoing delayed RTSA achieved 6° more external rotation than those undergoing acute RTSA; this difference was significant (P = .01).

CONCLUSIONS

Given the risks associated with surgery in the elderly population, consideration may be given to an initial trial of nonoperative treatment in these patients, saving RTSA for those in whom nonoperative treatment fails without compromising the ultimate outcome.

Proximal Femur Hounsfield Units on CT Colonoscopy Correlate With Dual-energy X-ray Absorptiometry

BACKGROUND

Quantifying bone mineral density (BMD) on CT using commercial software demonstrates good-to-excellent correlations with dual-energy x-ray absorptiometry (DEXA) results. However, previous techniques to measure Hounsfield units (HUs) within the proximal femur demonstrate less successful correlation with DEXA results. An effective method of measuring HUs of the proximal femur from CT colonoscopy might allow for opportunistic osteoporosis screening.

QUESTIONS/PURPOSES

(1) Do proximal femur HU measurements from CT colonoscopy correlate with proximal femur DEXA results? (2) How effective is our single HU measurement technique in estimating the likelihood of overall low BMD? (3) Does the relationship between our comprehensive HU measurement and DEXA results change based on age, sex, or time between studies?

METHODS

This retrospective study investigated the measurement of HU of the femur obtained on CT colonoscopy studies compared with DEXA results. Between 2010 and 2017, five centers performed 9085 CT colonoscopy studies; of those, 277 (3%) also had available DEXA results and were included in this study, whereas 8809 (97%) were excluded for inadequate CT imaging, lack of DEXA screening, or lack of proximal femur DEXA results. The median number of days between CT colonoscopy and DEXA scan was 595 days; no patient was excluded based on time between scans because bone remodeling is a long-term process and this allowed subgroup analysis based on time between scans. Two reviewers performed HU measurements at four points within the proximal femur on the CT colonoscopy imaging and intraclass correlation coefficients were used to evaluate interrater reliability. We used Pearson correlation coefficients to compare the comprehensive (average of eight measurements) and a single HU measurement with each DEXA result-proximal femur BMD, proximal femur T-score, femoral neck BMD, and femoral neck T-score-to identify the best measurement technique within this study. Based on their lowest DEXA T-score, we stratified patients to a diagnosis of osteoporosis, osteopenia, or normal BMD. We then calculated the area under the receiver operator characteristic curves (AUCs) to evaluate the classification ability of a single HU value to identify possible threshold(s) for detecting low BMD. For each subgroup analysis, we calculated Pearson correlation coefficients between DEXA and HUs and evaluated each subgroup's contribution to the overall predictive model using an interaction test in a linear regression model.

RESULTS

The Pearson correlation coefficient between both the comprehensive and single HU measurements was highest compared with the proximal femur T-score at 0.75 (95% confidence interval [CI], 0.69-0.80) and 0.74 (95% CI, 0.68-0.79), respectively. Interobserver reliability, measured with intraclass correlation coefficients, for the comprehensive and single HU measurements was 0.97 (95% CI, 0.72-0.99) and 0.96 (95% CI, 0.89-0.98), respectively. Based on DEXA results, 20 patients were osteoporotic, 167 had osteopenia, and 90 patients had normal BMD. The mean comprehensive HU for patients with osteoporosis was 70 ± 30 HUs; for patients with osteopenia, it was 110 ± 36 HUs; and for patients with normal BMD, it was 158 ± 43 HUs (p < 0.001). The AUC of the single HU model was 0.82 (95% CI, 0.77-0.87). A threshold of 214 HUs is 100% sensitive and 59 HUs is 100% specific to identify low BMD; a threshold of 113 HUs provided 73% sensitivity and 76% specificity. When stratified by decade age groups, each decade age group demonstrated a positive correlation between the comprehensive HU and proximal femur T-score, ranging between 0.71 and 0.83 (95% CI, 0.59-0.91). Further subgroup analysis similarly demonstrated a positive correlation between the comprehensive HU and proximal femur T-score when stratified by > 6 months or < 6 months between CT and DEXA (0.75; 95% CI, 0.62-0.84) as well as when stratified by sex (0.70-0.76; 95% CI, 0.48-0.81). The linear regression model demonstrated that the overall positive correlation coefficient between HUs and the proximal femur T-score is not influenced by any subgroup.

CONCLUSIONS

Our measurement technique provides a reproducible measurement of HUs within the proximal femur HUs on CT colonoscopy. Hounsfield units of the proximal femur based on this technique can predict low BMD. These CT scans are frequently performed before initial DEXA scans are done and therefore may lead to earlier recognition of low BMD. Future research is needed to validate these results in larger studies and to determine if these results can anticipate future fracture risk.

LEVEL OF EVIDENCE

Level III, diagnostic study.

Patterns of Opioid Use in the 12 Months Following Geriatric Fragility Fractures: A Population-Based Cohort Study

OBJECTIVES

Fractures of the hip, distal radius, and proximal humerus are common in the Medicare population. This study's objective was to characterize patterns and duration of opioid use, including regional variations in use, after both surgical and nonoperative management.

DESIGN

Population-based cohort study.

SETTING AND PARTICIPANTS

A cohort of opioid-naïve community-dwelling US Medicare beneficiaries who survived a hip, distal radius, or proximal humerus fracture between January 1, 2007 and December 31, 2010. Cohort members were required to be opioid-naïve for 4 months prior to fracture.

MEASURES

We analyzed the proportion of patients with an active opioid prescription in each month following the index fracture, and report continued fills at 12 months postfracture. We also compared opioid prescription use in fractures treated surgically and nonsurgically and characterized state-level variation in opioid prescription use at 3 months postfracture.

RESULTS

There were 91,749 patients included in the cohort. Hip fracture patients had the highest rate of opioid use at 12 months (6.4%), followed by proximal humerus (5.7%), and distal radius (3.7%). Patients who underwent surgical fixation of proximal humerus and wrist fractures had higher rates of opioid use in each of the first 12 postoperative months compared with those managed nonoperatively. There was significant variation of opioid use at the state level, ranging from 7.6% to 18.2% of fracture patients filling opioid prescriptions 3 months after the index fracture.

CONCLUSIONS/IMPLICATIONS

Opioid-naïve patients sustaining fragility fractures of the hip, proximal humerus, or distal radius are at risk to remain on opioid medications 12 months after their index injury, and surgical management of proximal humerus and distal radius fractures increases opioid use in the 12 months after the index fracture. There is significant state-level variation in opiate consumption after index fracture in nonvertebral geriatric fragility fractures. Opportunity exists for targeted quality improvement efforts to reduce the variation in opioid use following common geriatric fragility fractures.

Differences in youngest-old, middle-old, and oldest-old patients who visit the emergency department

Objective

As aging progresses, clinical characteristics of elderly patients in the emergency department (ED) vary by age. We aimed to study differences among elderly patients in the ED by age group.

Methods

For 2 years, patients aged 65 and older were enrolled in the study and classified into three groups: youngest-old, ages 65 to 74 years; middle-old, 75 to 84 years; and oldest-old, ≥85 years. Participants’ sex, reason for ED visit, transfer from another hospital, results of treatment, type of admission, admission department and length of stay were recorded.

Results

During the study period, a total 64,287 patients visited the ED; 11,236 (17.5%) were aged 65 and older, of whom 14.4% were 85 and older. With increased age, the female ratio (51.5% vs. 54.9% vs. 69.1%, P<0.001), medical causes (79.5% vs. 81.3% vs. 81.7%, P=0.045), and admission rate (35.3% vs. 42.8% vs. 48.5%, P<0.001) increased. Admissions to internal medicine (57.5% vs. 59.3% vs. 64.7%, P<0.001) and orthopedic surgery (8.5% vs. 11.6% vs. 13.8%, P< 0.001) also increased. The ratio of admission to intensive care unit showed no statistical significance (P=0.545). Patients over age 85 years had longer stays in the ED (330.9 vs. 378.9 vs. 407.2 minutes, P<0.001), were discharged home less (84.4% vs. 78.9% vs. 71.5%, P<0.001), and died more frequently (6.3% vs. 10.4% vs. 13.0%, P<0.001).

Conclusion

With increased age, the proportion of female patients and medical causes increased. Rates of admission and death increased with age and older patients had longer ED and hospital stays.

The Influence of Cortical Porosity on the Strength of Bone During Growth and Advancing Age

PURPOSE OF REVIEW

Bone densitometry provides a two-dimensional projected areal apparent bone mineral density that fails to capture the heterogeneity of bone's material composition and macro-, micro-, and nano-structures critical to its material and structural strength. Assessment of the structural basis of bone fragility has focused largely on trabecular bone based on the common occurrence of fragility fractures at sites with substantial amounts of trabecular bone. This review focuses on the contribution of cortical bone to bone fragility throughout life.

RECENT FINDINGS

Accurately differentiating cortical and trabecular bone loss has important implications in quantifying bone fragility as these compartments have differing effects on bone strength. Recent advances in imaging methodology have improved distinction of these two compartments by (i) recognition of a cortico-trabecular transitional zone and (ii) quantifying bone microstructure in a region of interest that is a percentage of bone length rather than a fixed point. Additionally, non-invasive three-dimensional imaging methods allow more accurate quantification of changes in the cortical, trabecular, and cortico-trabecular compartments during growth, aging, disease, and treatment. Over 75% of the skeleton is assembled as cortical bone. Of all fragility fractures, ~ 80% are appendicular and involve regions rich in cortical bone and ~ 70% of all age-related appendicular bone loss is cortical and is mainly due to unbalanced intracortical remodeling which increases cortical porosity. The failure to achieve the optimal peak bone microstructure during growth due to disease and the deterioration in cortical and trabecular bone produced by bone loss compromise bone strength. The loss of strength produced by microstructural deterioration is disproportionate to the bone loss producing this deterioration. The reason for this is that the loss of strength increases as a 7th power function of the rise in cortical porosity and a 3rd power function of the fall in trabecular density (Schaffler and Burr in J Biomech. 21(1):13-6, 1988), hence the need to quantify bone microstructure.

Advances and Unmet Needs in the Therapeutics of Bone Fragility

The prevalence of fragility fractures increases as longevity increases the proportion of the elderly in the community. Until recently, the majority of studies have targeted women with osteoporosis defined as a bone mineral density (BMD) T score of < -2.5 SD, despite evidence that the population burden of fractures arises from women with osteopenia. Antiresorptive agents reduce vertebral and hip fracture risk by ~50 percent during 3 years but efficacy against non-vertebral fractures, 80% of all fractures in the community, is reported in few studies, and of those, the risk reduction is only 20-30%. Recent advances in the use of antiresorptives and anabolic agents has addressed some of these unmet needs. Zoledronic acid is now reported to reduce vertebral and non-vertebral fractures rates in women with osteopenia. Studies using teriparatide demonstrate better vertebral and clinical (symptomatic vertebral and non-vertebral) antifracture efficacy than risedronate. Abaloparatide, a peptide sharing amino acid sequences with teriparatide, reduces vertebral and non-vertebral fractures. Romosozumab, a monoclonal antibody suppressing sclerostin, reduces vertebral and non-vertebral fractures within a year of starting treatment, and does so more greatly than alendronate. Some recent studies signal undesirable effects of therapy but provide essential cautionary insights into long term management. Cessation of denosumab is associated with a rapid increase in bone remodeling and the uncommon but clinically important observation of increased multiple vertebral fractures suggesting the need to start alternative anti-resorptive therapy around the time of stopping denosumab. Antiresorptives like bisphosphonates and denosumab suppress remodeling but not completely. Antifracture efficacy may be limited, in part, as a consequence of continued unsuppressed remodeling, particularly in cortical bone. Bisphosphonates may not distribute in deeper cortical bone, so unbalanced intracortical remodeling continues to cause microstructural deterioration. In addition, suppressed remodeling may compromise the material composition by increasing matrix mineral density and glycosylation of collagen. As antiresorptive agents do not restore microstructural deterioration existing at the time of starting treatment, under some circumstances, anabolic therapy may be more appropriate first line treatment. Combining antiresorptive and anabolic therapy is an alternative but whether anti-fracture efficacy is greater than that achieved by either treatment alone is not known.

Association of trabecular bone score (TBS) and prior fracture differs among minorities in NHANES 2005-2008

The study investigates the association of trabecular bone score (TBS) and fractures among minority populations. In NHANES 2005-2008, TBS was associated with history of fractures in Caucasian subjects but demonstrated somewhat weaker associations in African American and Mexican American women.

INTRODUCTION

Trabecular bone score (TBS), a textural analysis of the lumbar spine DXA image, predicts fractures well in Caucasian (CA) and Asian populations but is less well studied in African American (AA) and Mexican American (MA) subjects. It is not clear whether TBS is associated with or is predictive of fragility in these racial/ethnic groups.

METHODS

We analyzed data from subjects from NHANES 2005-2008 over the age of 40 who had TBS: 1178 CA, 467 AA, and 397 MA women and 1200 CA, 502 AA, and 386 MA men. TBS was categorized into normal, ≥ 1.310, partially degraded < 1.310, and > 1.230, or degraded, ≤ 1.230. History of fracture was assessed by questionnaire.

RESULTS

Among women, there was an increasing prevalence of fracture with worsening TBS category. However, when controlling for age, BMI, and low T-score, the association between TBS category and previous fracture was only significant in CA women (OR 1.49 per worsening category, 95% CI 1.20-1.85). In men, there was also an increase in the prevalence of fracture with worsening TBS category in all races/ethnicities. When controlling for age, BMI, and low T-score, the association between TBS category and previous fracture was only significant in CA men (OR 1.47 per worsening category, 95% CI 1.10-1.95), though analysis was somewhat limited by small fracture numbers.

CONCLUSIONS

The association of fracture and TBS varies by race/ethnicity and gender with weaker association observed in AA and MA women. More research is needed to define the proper use of TBS for predicting fractures in minority groups.

The challenges of diagnosing osteoporosis and the limitations of currently available tools

Dual-energy X-ray absorptiometry (DXA) was the first imaging tool widely utilized by clinicians to assess fracture risk, especially in postmenopausal women. The development of DXA nearly coincided with the availability of effective osteoporosis medications. Although osteoporosis in adults is diagnosed based on a T-score equal to or below − 2.5 SD, most individuals who sustain fragility fractures are above this arbitrary cutoff. This incongruity poses a challenge to clinicians to identify patients who may benefit from osteoporosis treatments. DXA scanners generate 2 dimensional images of complex 3 dimensional structures, and report bone density as the quotient of the bone mineral content divided by the bone area. An obvious pitfall of this method is that a larger bone will convey superior strength, but may in fact have the same bone density as a smaller bone. Other imaging modalities are available such as peripheral quantitative CT, but are largely research tools. Current osteoporosis medications increase bone density and reduce fracture risk but the mechanisms of these actions vary. Anti-resorptive medications (bisphosphonates and denosumab) primarily increase endocortical bone by bolstering mineralization of endosteal resorption pits and thereby increase cortical thickness and reduce cortical porosity. Anabolic medications (teriparatide and abaloparatide) increase the periosteal and endosteal perimeters without large changes in cortical thickness resulting in a larger more structurally sound bone. Because of the differences in the mechanisms of the various drugs, there are likely benefits of selecting a treatment based on a patient’s unique bone structure and pattern of bone loss. This review retreats to basic principles in order to advance clinical management of fragility fractures by examining how skeletal biomechanics, size, shape, and ultra-structural properties are the ultimate predictors of bone strength. Accurate measurement of these skeletal parameters through the development of better imaging scanners is critical to advancing fracture risk assessment and informing clinicians on the best treatment strategy. With this information, a “treat to target” approach could be employed to tailor current and future therapies to each patient’s unique skeletal characteristics.

Regional variations of cortical bone in the humeral head region: A preliminary study

BACKGROUND

Incidence of proximal humeral fractures dramatically increased over the last decade due to demographic changes. The goal of this study was to analyze regional characteristics of cortical bone in the humeral head region using cortical bone mapping (CBM) technique.

METHODS

The proximal humerus of 103 healthy volunteers was imaged by clinical computed tomography (CT) scans. Three groups of volunteers were identified according to age: group A (20-39years), group B (40-59years), and group C (>60years). CBM was applied to create color 3D thickness maps for each proximal humerus. Cortical parameters, including the cortical thickness (CTh), cortical mass surface density (CM), and the endocortical trabecular density (ECTD) were measured over humeral head region after nine regions of interest (ROI) were defined.

RESULTS

Cortical bone structure of the humeral head region varied dramatically in cross-section independent of age, with significant cortical thinning at the posterior wall. Particularly, notable cortical thinning was also found in the distal end of lateral wall at 60years of age or older. The degree of regional variability of cortical properties within lateral wall tended to diminish with age.

CONCLUSION

Substantial regional variations in cortical bone structure at humeral head region were observed quantitatively in this study. These morphologic data provided useful information on clinical medicine such as surgical fixation.

Do reductions in out-of-pocket expenses for dual energy X-ray absorptiometry scans translate to reduced fracture incidence amongst older Australians? A population-based study

This study aimed to compare fracture incidence in the elderly pre- and post-revision of bone density scan reimbursement guidelines, which changed in 2007. Fracture incidence by age group was calculated using population-specific data. Guideline changes did not appear to reduce fracture incidence in the study region located in south-eastern Australia.

PURPOSE

In 2007, Medicare Australia revised reimbursement guidelines whereby individuals aged 70 years and over received reduced out-of-pocket expenses for dual energy X-ray absorptiometry (DXA) scans. The current study aims to determine whether fracture incidence in the elderly has changed since the revision of reimbursement guidelines.

METHOD

Keyword searches of the two major radiological centres servicing the Barwon Statistical Division (BSD) were used to identify incident fractures for residents aged 75 years and over for 2006 and 2012. Pathological fractures were excluded. Fracture incidence by age strata (75-79 years, 80-84 years and 85+ years) were calculated using population-specific data from the Australian Bureau of Statistics (2006 and 2012). Standardised fracture ratios were calculated for men and women.

RESULTS

In total, 996 fracture events were identified for BSD residents during 2006 and 1260 identified in 2012. The standardised fracture ratios between 2006 and 2012 were 1.12 (95%CI 1.11, 1.25) for men and 1.08 (95%CI 1.11, 1.16) for women.

CONCLUSION

The change in reimbursement guidelines appears to have had little impact on reducing fracture incidence during this time frame for elderly men and women, in fact, fracture rates increased. Future research should investigate osteoporosis management following DXA over a longer time frame.

Appropriateness of bone density measurement in Switzerland: a cross-sectional study

Background

According to the WHO, osteoporosis is one of the most important non- communicable diseases worldwide. Different screening procedures are controversially discussed, especially concerning the concomitant issues of overdiagnosis and harm caused by inappropriate Dual X-ray Absorptiometry (DXA). The aim of this study was to evaluate the frequency and appropriateness of DXA as screening measure in Switzerland considering individual risk factors and to evaluate covariates independently associated with potentially inappropriate DXA screening.

Methods

Retrospective cross-sectional study using insurance claim data of 2013. Among all patients with DXA screening, women < 65 and men < 70 years without osteoporosis or risk factors for osteoporosis were defined as receiving potentially inappropriate DXA. Statistics included descriptive measures and multivariable regressions to estimate associations of relevant covariates with potentially inappropriate DXA screening.

Results

Of 1,131,092 patients, 552,973 were eligible. Among those 2637 of 10,000 (26.4%) underwent potentially inappropriate DXA screening. Female sex (Odds ratio 6.47, CI 6.41–6.54) and higher age showed the strongest association with any DXA screening.

Female gender (Odds ratio 1.84, CI 1.49–2.26) and an income among the highest 5% (Odds ratio 1.40, CI 1.01–1.98) were significantly positively associated with potentially inappropriate DXA screening, number of chronic conditions (Odds ratio 0.67, CI 0.65–0.70) and living in the central region of Switzerland (Odds ratio 0.67, CI 0.48–0.95) negatively.

Conclusion

One out of four DXAs for screening purpose is potentially inappropriate. Stakeholders of osteoporosis screening campaigns should focus on providing more detailed information on appropriateness of DXA screening indications (e.g. age thresholds) in order to avoid DXA overuse.

Electronic supplementary material

The online version of this article (10.1186/s12889-018-5305-0) contains supplementary material, which is available to authorized users.

How does the femoral cortex depend on bone shape? A methodology for the joint analysis of surface texture and shape

In humans, there is clear evidence of an association between hip fracture risk and femoral neck bone mineral density, and some evidence of an association between fracture risk and the shape of the proximal femur. Here, we investigate whether the femoral cortex plays a role in these associations: do particular morphologies predispose to weaker cortices? To answer this question, we used cortical bone mapping to measure the distribution of cortical mass surface density (CMSD, mg/cm2) in a cohort of 125 females. Principal component analysis of the femoral surfaces identified three modes of shape variation accounting for 65% of the population variance. We then used statistical parametric mapping (SPM) to locate regions of the cortex where CMSD depends on shape, allowing for age. Our principal findings were increased CMSD with increased gracility over much of the proximal femur; and decreased CMSD at the superior femoral neck, coupled with increased CMSD at the calcar femorale, with increasing neck-shaft angle. In obtaining these results, we studied the role of spatial normalization in SPM, identifying systematic misregistration as a major impediment to the joint analysis of CMSD and shape. Through a series of experiments on synthetic data, we evaluated a number of registration methods for spatial normalization, concluding that only those predicated on an explicit set of homologous landmarks are suitable for this kind of analysis. The emergent methodology amounts to an extension of Geometric Morphometric Image Analysis to the domain of textured surfaces, alongside a protocol for labelling homologous landmarks in clinical CT scans of the human proximal femur.

Association between obesity and femoral neck strength according to age, sex, and fat distribution

Indicators of total and abdominal obesity were negatively associated with femoral neck strength indices. There are age-, sex-, and fat distribution-specific differences in the magnitude of these associations. These suggested that indicators of obesity with different magnitude according to age, sex, and fat distribution associated with poor bone health.

INTRODUCTION

Fat regulates bone metabolism, but the associations of total and abdominal obesity with bone health are inconsistent. We investigated the association between indicators of obesity and composite indices of femoral neck (FN) strength reflecting the risk of hip fracture.

METHODS

This population-based cross-sectional study examined data from the Korea National Health and Nutrition Examination Surveys. Participants were divided into groups according to age (25-49/≥50 years) and sex. We examined total fat mass (TFM) and percentage fat mass (pFM) as indicators of total obesity and truncal fat mass (TrFM) as an indicator of abdominal obesity. We calculated the composite indices of FN strength and anthropometric clinical indicators of abdominal obesity.

RESULTS

TFM, pFM, and TrFM were negatively associated with the composite indices, irrespective of age and sex (P < 0.001-0.005). Most anthropometric clinical indicators of abdominal obesity showed negative associations with the composite indices regardless of age and sex (P < 0.001-0.048), except for women aged 25-49 years. In men, magnitudes of the negative contributions of TFM to the composite indices were significantly stronger at age 25-49 years than at age ≥50 years. Magnitudes of negative associations of TFM with the composite indices were greater in men than in women. TrFM had a more detrimental effect than TFM on FN strength in men aged 25-49 years and in women of both ages.

CONCLUSION

Indicators of total and abdominal obesity negatively associated with FN strength, and magnitudes of their effects on bone health differed according to age, sex, and fat distribution.

Long-term effects of bisphosphonate therapy: perforations, microcracks and mechanical properties

Osteoporosis is characterised by trabecular bone loss resulting from increased osteoclast activation and unbalanced coupling between resorption and formation, which induces a thinning of trabeculae and trabecular perforations. Bisphosphonates are the frontline therapy for osteoporosis, which act by reducing bone remodelling, and are thought to prevent perforations and maintain microstructure. However, bisphosphonates may oversuppress remodelling resulting in accumulation of microcracks. This paper aims to investigate the effect of bisphosphonate treatment on microstructure and mechanical strength. Assessment of microdamage within the trabecular bone core was performed using synchrotron X-ray micro-CT linked to image analysis software. Bone from bisphosphonate-treated fracture patients exhibited fewer perforations but more numerous and larger microcracks than both fracture and non-fracture controls. Furthermore, bisphosphonate-treated bone demonstrated reduced tensile strength and Young's Modulus. These findings suggest that bisphosphonate therapy is effective at reducing perforations but may also cause microcrack accumulation, leading to a loss of microstructural integrity and consequently, reduced mechanical strength.