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

Exercise and Sports Science Australia (ESSA) position statement on exercise prescription for the prevention and management of osteoporosis

OBJECTIVES

Osteoporotic fractures are associated with substantial morbidity and mortality. Although exercise has long been recommended for the prevention and management of osteoporosis, existing guidelines are often non-specific and do not account for individual differences in bone health, fracture risk and functional capacity. The aim of the current position statement is to provide health practitioners with specific, evidence-based guidelines for safe and effective exercise prescription for the prevention or management of osteoporosis, accommodating a range of potential comorbidities.

DESIGN

Position statement.

METHODS

Interpretation and application of research reports describing the effects of exercise interventions for the prevention and management of low bone mass, osteoporosis and osteoporotic fracture.

RESULTS

Evidence from animal and human trials indicates that bone responds positively to impact activities and high intensity progressive resistance training. Furthermore, the optimisation of muscle strength, balance and mobility minimises the risk of falls (and thereby fracture), which is particularly relevant for individuals with limited functional capacity and/or a very high risk of osteoporotic fracture. It is important that all exercise programs be accompanied by sufficient calcium and vitamin D, and address issues of comorbidity and safety. For example, loaded spine flexion is not recommended, and impact activities may require modification in the presence of osteoarthritis or frailty.

CONCLUSIONS

Specific guidelines for safe and effective exercise for bone health are presented. Individual exercise prescription must take into account existing bone health status, co-morbidities, and functional or clinical risk factors for falls and fracture.

Cortical Bone Porosity: What Is It, Why Is It Important, and How Can We Detect It?

There is growing recognition of the role of micro-architecture in osteoporotic bone loss and fragility. This trend has been driven by advances in imaging technology, which have enabled a transition from measures of mass to micro-architecture. Imaging trabecular bone has been a key research focus, but advances in resolution have also enabled the detection of cortical bone micro-architecture, particularly the network of vascular canals, commonly referred to as 'cortical porosity.' This review aims to provide an overview of what this level of porosity is, why it is important, and how it can be characterized by imaging. Moving beyond a 'trabeculocentric' view of bone loss holds the potential to improve diagnosis and monitoring of interventions. Furthermore, cortical porosity is intimately linked to the remodeling process, which underpins bone loss, and thus a larger potential exists to improve our fundamental understanding of bone health through imaging of both humans and animal models.

Value of Measuring Bone Microarchitecture in Fracture Discrimination in Older Women with Recent Hip Fracture: A Case-control Study with HR-pQCT

We aimed to determine whether loss of volumetric bone mineral density (vBMD) and deterioration of microarchitecture imaged by high-resolution peripheral quantitative computed tomography at the distal radius/tibia provided additional information in fracture discrimination in postmenopausal women with recent hip fracture. This case-control study involved 24 postmenopausal Chinese women with unilateral femoral neck fracture (average [SD] age: 79.6[5.6]) and 24 age-matched women without any history of fracture. Each SD decrease in T-score at femoral neck (FN) was associated with a higher fracture risk (odds ratio: 6.905, p = 0.001). At the distal radius, fracture women had significantly lower total vBMD (−17.5%), fewer (−20.3%) and more unevenly spaced (81.4%) trabeculae, and thinner cortices (−14.0%) (all p < 0.05). At the distal tibia, vBMD was on average −4.7% (cortical) to −25.4% (total) lower, trabecular microarchitecture was on average −19.8% (number) to 102% (inhomogeneity) inferior, cortices were thinner (−21.1%) and more porous (18.2%) (all p < 0.05). Adding parameters of vBMD and microarchitecture in multivariate models did not offer additional discriminative capacity of fracture status compared with using T-score at FN. In old postmenopausal women with already excessive loss of bone mass, measuring bone microarchitecture may provide limited added value to improve identification of risk of femoral neck fracture.

The circulating sphingosine-1-phosphate level predicts incident fracture in postmenopausal women: a 3.5-year follow-up observation study

A high level of circulating sphingosine-1-phosphate (S1P) is associated with a high incidence of osteoporotic fracture and a high rate of an insufficient response to bisphosphonate therapy.

INTRODUCTION

Sphingosine-1-phosphate (S1P) is a significant regulator of bone metabolism. Recently, we found that a high plasma S1P level is associated with low bone mineral density (BMD), high levels of bone resorption markers (BRMs), and a high risk of prevalent vertebral fracture in postmenopausal women. We investigated the possibility that S1P is a predictor of incident fracture.

METHODS

A total of 248 postmenopausal women participated in this longitudinal study and were followed up for a mean duration of 3.5 years (untreated [n = 76] or treated with bisphosphonate or hormone replacement therapy [n = 172]). The baseline plasma S1P level and prevalent and incident fracture occurrence were assessed.

RESULTS

A high S1P level was significantly associated with a higher rate of prevalent fracture after adjusting for femoral neck (FN) BMD, BRM, and potential confounders (odds ratio = 2.05; 95 % confidence interval [CI] = 1.03-4.00). Incident fractures occurred more frequently in the highest S1P tertile (T3) than in the lower two tertiles (T1-2) after adjusting for confounders, including baseline FN BMD, prevalent fracture, antiosteoporotic medication, annualized changes in FN BMD, BRM, and potential confounders (hazard ratio = 5.52; 95 % CI = 1.04-56.54). Insufficient response to bisphosphonate therapy occurred more frequently in T3 than T1-2 (odds ratio = 4.43; 95 % CI = 1.02-21.25).

CONCLUSIONS

The plasma S1P level may be a potential predictor of fracture occurrence and an insufficient response to bisphosphonate therapy in postmenopausal women.

A randomised controlled trial of low-dose aspirin for the prevention of fractures in healthy older people: protocol for the ASPREE-Fracture substudy

BACKGROUND

Disability, mortality and healthcare burden from fractures in older people is a growing problem worldwide. Observational studies suggest that aspirin may reduce fracture risk. While these studies provide room for optimism, randomised controlled trials are needed. This paper describes the rationale and design of the ASPirin in Reducing Events in the Elderly (ASPREE)-Fracture substudy, which aims to determine whether daily low-dose aspirin decreases fracture risk in healthy older people.

METHODS

ASPREE is a double-blind, randomised, placebo-controlled primary prevention trial designed to assess whether daily active treatment using low-dose aspirin extends the duration of disability-free and dementia-free life in 19 000 healthy older people recruited from Australian and US community settings. This substudy extends the ASPREE trial data collection to determine the effect of daily low-dose aspirin on fracture and fall-related hospital presentation risk in the 16 500 ASPREE participants aged ≥70 years recruited in Australia. The intervention is a once daily dose of enteric-coated aspirin (100 mg) versus a matching placebo, randomised on a 1:1 basis. The primary outcome for this substudy is the occurrence of any fracture-vertebral, hip and non-vert-non-hip-occurring post randomisation. Fall-related hospital presentations are a secondary outcome.

DISCUSSION

This substudy will determine whether a widely available, simple and inexpensive health intervention-aspirin-reduces the risk of fractures in older Australians. If it is demonstrated to safely reduce the risk of fractures and serious falls, it is possible that aspirin might provide a means of fracture prevention.

TRIAL REGISTRATION NUMBER

The protocol for this substudy is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12615000347561).

Evidence of effectiveness of a fracture liaison service to reduce the re-fracture rate

SUMMARY

We assessed the ability of a fracture liaison service (FLS) to directly reduce re-fracture risk. Having a FLS is associated with a ∼40% reduction in the 3-year risk of major bone and ∼30% of any bone re-fracture. The number needed to treat to prevent a re-fracture is 20.

INTRODUCTION

FLS have been promoted as the most effective interventions for secondary fracture prevention, and while there is evidence of increased rate of investigation and treatment at institutions with a FLS, only a few studies have considered fracture outcomes directly. We therefore sought to evaluate the ability of our FLS to reduce re-fracture risk.

METHODS

Historical cohort study of all patients ≥50 years presenting over a 6-month period with a minimal trauma fracture (MTF) to the emergency departments of a tertiary hospital with a FLS, and one without a FLS. Baseline characteristics, mortality and MTFs over a 3-year follow-up were recorded.

RESULTS

Five hundred fifteen patients at the FLS hospital and 416 patients at the non-FLS hospital were studied. Over 3 years, 63/515 (12%) patients at the FLS hospital and 70/416 (17%) at the non-FLS hospital had a MTF. All patients were analysed in an intention-to-treat analysis regardless of whether they were seen in the FLS follow-up clinic. Statistical analysis using Cox proportional hazard models in the presence of a competing risk of death from any cause was used. After adjustment for baseline characteristics, there was a ∼30% reduction in rate of any re-fracture at the FLS hospital (hazard ratio (HR) 0.67, confidence interval (CI) 0.47-0.95, p value 0.025) and a ∼40% reduction in major re-fractures (hip, spine, femur, pelvis or humerus) (HR 0.59, CI 0.39-0.90, p value 0.013).

CONCLUSIONS

We found a ∼30% reduction in any re-fractures and a ∼40% reduction in major re-fractures at the FLS hospital compared with a similar non-FLS hospital. The number of patients needed to treat to prevent one new fracture over 3 years is 20.

The effect of sphingosine-1-phosphate on bone metabolism in humans depends on its plasma/bone marrow gradient

BACKGROUND

Although recent studies provide clinical evidence that sphingosine-1-phosphate (S1P) may primarily affect bone resorption in humans, rather than bone formation or the osteoclast-osteoblast coupling phenomenon, those studies could not determine which bone resorption mechanism is more important, i.e., chemorepulsion of osteoclast precursors via the blood to bone marrow S1P gradient or receptor activator of NF-κB ligand (RANKL) elevation in osteoblasts via local S1P.

AIM

To investigate how S1P mainly contributes to increased bone resorption in humans, we performed this case-control study at a clinical unit in Korea.

METHODS

Blood and bone marrow samples were contemporaneously collected from 70 patients who underwent hip surgery due to either osteoporotic hip fracture (HF) (n = 10) or other causes such as osteoarthritis (n = 60).

RESULTS

After adjusting for sex, age, BMI, smoking, alcohol, previous fracture, diabetes, and stroke, subjects with osteoporotic HF demonstrated a 3.2-fold higher plasma/bone marrow S1P ratio than those without HF, whereas plasma and bone marrow S1P levels were not significantly different between these groups. Consistently, the risk of osteoporotic HF increased 1.38-fold per increment in the plasma/bone marrow S1P ratio in a multivariate adjustment model. However, the odds ratios for prevalent HF according to the increment in the plasma and bone marrow S1P level were not statistically significant.

CONCLUSION

Our current results using simultaneously collected blood and bone marrow samples suggest that the detrimental effects of S1P on bone metabolism in humans may depend on the S1P gradient between the peripheral blood and bone marrow cavity.

Growth and Age-Related Abnormalities in Cortical Structure and Fracture Risk

Vertebral fractures and trabecular bone loss have dominated thinking and research into the pathogenesis and the structural basis of bone fragility during the last 70 years. However, 80% of all fractures are non-vertebral and occur at regions assembled using large amounts of cortical bone; only 20% of fractures are vertebral. Moreover, ~80% of the skeleton is cortical and ~70% of all bone loss is cortical even though trabecular bone is lost more rapidly than cortical bone. Bone is lost because remodelling becomes unbalanced after midlife. Most cortical bone loss occurs by intracortical, not endocortical remodelling. Each remodelling event removes more bone than deposited enlarging existing canals which eventually coalesce eroding and thinning the cortex from 'within.' Thus, there is a need to study the decay of cortical as well as trabecular bone, and to develop drugs that restore the strength of both types of bone. It is now possible to accurately quantify cortical porosity and trabecular decay in vivo. The challenges still to be met are to determine whether measurement of porosity identifies persons at risk for fracture, whether this approach is compliments information obtained using bone densitometry, and whether changes in cortical porosity and other microstructural traits have the sensitivity to serve as surrogates of treatment success or failure.

Plasma periostin associates significantly with non-vertebral but not vertebral fractures in postmenopausal women: Clinical evidence for the different effects of periostin depending on the skeletal site

BACKGROUND

Periostin is preferentially expressed by the periosteum, which mainly covers the long bones. Therefore, the role of periostin in osteoporotic fracture (OF) may differ depending on bone type. We performed a case-control study to investigate whether periostin can serve as a predictor of OF risk, particularly after dividing OFs into non-vertebral and vertebral fractures.

METHODS

Among 532 consecutive postmenopausal women not taking any drug or without any disease that could affect bone metabolism, 133 cases with OF (i.e., non-vertebral and/or vertebral fractures) and 133 age- and body mass index-matched controls were enrolled. Non-vertebral (i.e., forearm, humerus, hip, and pelvis; n=81) and morphological vertebral (n=62) fractures were identified by an interviewer-assisted questionnaire and lateral thoracolumbar radiographs, respectively. Bone mineral density (BMD) and plasma periostin levels were also measured.

RESULTS

Plasma periostin was markedly higher in subjects with non-vertebral fracture than their controls even after adjustment for BMD and potential confounders (P=0.006). Each standard deviation increment of plasma periostin was associated with a multivariable-adjusted odds ratio of 1.59 for non-vertebral fracture. The odds for non-vertebral fracture were 2.48-fold higher in subjects in the highest periostin tertile compared with those in the lowest periostin tertile (95% confidence interval=1.10-5.61). However, associations between plasma periostin and vertebral fracture were not observed, regardless of the adjustment model used. Consistently, plasma periostin levels were inversely associated with proximal femur BMD (P=0.007 to 0.030) but not lumbar spine BMD. In subgroup analyses, plasma periostin had no correlation with the levels of classical bone turnover markers.

CONCLUSIONS

Plasma periostin may be a potential biomarker of the risk of OF, especially in non-spinal skeletal sites, such as the limbs, rather than spine.

Predicting Hip Fracture Type With Cortical Bone Mapping (CBM) in the Osteoporotic Fractures in Men (MrOS) Study

Hip fracture risk is known to be related to material properties of the proximal femur, but fracture prediction studies adding richer quantitative computed tomography (QCT) measures to dual-energy X-ray (DXA)-based methods have shown limited improvement. Fracture types have distinct relationships to predictors, but few studies have subdivided fracture into types, because this necessitates regional measurements and more fracture cases. This work makes use of cortical bone mapping (CBM) to accurately assess, with no prior anatomical presumptions, the distribution of properties related to fracture type. CBM uses QCT data to measure the cortical and trabecular properties, accurate even for thin cortices below the imaging resolution. The Osteoporotic Fractures in Men (MrOS) study is a predictive case-cohort study of men over 65 years old: we analyze 99 fracture cases (44 trochanteric and 55 femoral neck) compared to a cohort of 308, randomly selected from 5994. To our knowledge, this is the largest QCT-based predictive hip fracture study to date, and the first to incorporate CBM analysis into fracture prediction. We show that both cortical mass surface density and endocortical trabecular BMD are significantly different in fracture cases versus cohort, in regions appropriate to fracture type. We incorporate these regions into predictive models using Cox proportional hazards regression to estimate hazard ratios, and logistic regression to estimate area under the receiver operating characteristic curve (AUC). Adding CBM to DXA-based BMD leads to a small but significant (p < 0.005) improvement in model prediction for any fracture, with AUC increasing from 0.78 to 0.79, assessed using leave-one-out cross-validation. For specific fracture types, the improvement is more significant (p < 0.0001), with AUC increasing from 0.71 to 0.77 for trochanteric fractures and 0.76 to 0.82 for femoral neck fractures. In contrast, adding DXA-based BMD to a CBM-based predictive model does not result in any significant improvement.

Identifying osteoporotic vertebral fracture

Osteoporosis per se is not a harmful disease. It is the sequela of osteoporosis and most particularly the occurrence of osteoporotic fracture that makes osteoporosis a serious medical condition. All of the preventative measures, investigations, treatment and research into osteoporosis have one primary goal and that is to prevent the occurrence of osteoporotic fracture. Vertebral fracture is by far and away the most prevalent osteoporotic fracture. The significance and diagnosis of vertebral fracture are discussed in this article.

Prediction of local ultimate strain and toughness of trabecular bone tissue by Raman material composition analysis

Clinical studies indicate that bone mineral density correlates with fracture risk at the population level but does not correlate with individual fracture risk well. Current research aims to better understand the failure mechanism of bone and to identify key determinants of bone quality, thus improving fracture risk prediction. To get a better understanding of bone strength, it is important to analyze tissue-level properties not influenced by macro- or microarchitectural factors. The aim of this pilot study was to identify whether and to what extent material properties are correlated with mechanical properties at the tissue level. The influence of macro- or microarchitectural factors was excluded by testing individual trabeculae. Previously reported data of mechanical parameters measured in single trabeculae under tension and bending and its compositional properties measured by Raman spectroscopy was evaluated. Linear and multivariate regressions show that bone matrix quality but not quantity was significantly and independently correlated with the tissue-level ultimate strain and postyield work (r = 0.65–0.94). Principal component analysis extracted three independent components explaining 86% of the total variance, representing elastic, yield, and ultimate components according to the included mechanical parameters. Some matrix parameters were both included in the ultimate component, indicating that the variation in ultimate strain and postyield work could be largely explained by Raman-derived compositional parameters.

Independent measurement of femoral cortical thickness and cortical bone density using clinical CT

The local structure of the proximal femoral cortex is of interest since both fracture risk, and the effects of various interventions aimed at reducing that risk, are associated with cortical properties focused in particular regions rather than dispersed over the whole bone. Much of the femoral cortex is less than 3mm thick, appearing so blurred in clinical CT that its actual density is not apparent in the data, and neither thresholding nor full-width half-maximum techniques are capable of determining its width. Our previous work on cortical bone mapping showed how to produce more accurate estimates of cortical thickness by assuming a fixed value of the cortical density for each hip. However, although cortical density varies much less over the proximal femur than thickness, what little variation there is leads to errors in thickness measurement. In this paper, we develop the cortical bone mapping technique by exploiting local estimates of imaging blur to correct the global density estimate, thus providing a local density estimate as well as more accurate estimates of thickness. We also consider measurement of cortical mass surface density and the density of trabecular bone immediately adjacent to the cortex. Performance is assessed with ex vivo clinical QCT scans of proximal femurs, with true values derived from high resolution HRpQCT scans of the same bones. We demonstrate superior estimation of thickness than is possible with alternative techniques (accuracy 0.12 ± 0.39 mm for cortices in the range 1-3mm), and that local cortical density estimation is feasible for densities >800 mg/cm(3).

Fatigue microcracks that initiate fracture are located near elevated intracortical porosity but not elevated mineralization

In vivo microcracks in cortical bone are typically observed within more highly mineralized interstitial tissue, but postmortem investigations are inherently limited to cracks that did not lead to fracture which may be misleading with respect to understanding fracture mechanisms. We hypothesized that the one fatigue microcrack which initiates fracture is located spatially adjacent to elevated intracortical porosity but not elevated mineralization. Therefore, the spatial correlation between intracortical porosity, elevated mineralization, and fatigue microdamage was investigated by combining, for the first time, sequential, nondestructive, three-dimensional micro-computed tomography (micro-CT) measurements of each in cortical bone specimens subjected to compressive fatigue loading followed by a tensile overload to fracture. Fatigue loading resulted in significant microdamage accumulation and compromised mechanical properties upon tensile overload compared to control specimens. The microdamage that initiated fracture upon tensile overload was able to be identified in all fatigue-loaded specimens using contrast-enhanced micro-CT and registered images. Two-point (or pair) correlation functions revealed a spatial correlation between microdamage at the fracture initiation site and intracortical porosity, but not highly mineralized tissue, confirming the hypothesis. This difference was unique to the fracture initiation site. Intracortical porosity and highly mineralized tissue exhibited a significantly lower and higher probability, respectively, of being located spatially adjacent to all sites of microdamage compared to the fracture initiation site. Therefore, the results of this study suggest that human cortical bone is tolerant of most microcracks, which are generally compartmentalized within the more highly mineralized interstitial tissue, but a single microcrack of sufficient size located in spatial proximity to intracortical porosity can compromise fracture resistance.

Cortical porosity identifies women with osteopenia at increased risk for forearm fractures

Most fragility fractures arise among the many women with osteopenia, not the smaller number with osteoporosis at high risk for fracture. Thus, most women at risk for fracture assessed only by measuring areal bone mineral density (aBMD) will remain untreated. We measured cortical porosity and trabecular bone volume/total volume (BV/TV) of the ultradistal radius (UDR) using high-resolution peripheral quantitative computed tomography, aBMD using densitometry, and 10-year fracture probability using the country-specific fracture risk assessment tool (FRAX) in 68 postmenopausal women with forearm fractures and 70 age-matched community controls in Olmsted County, MN, USA. Women with forearm fractures had 0.4 standard deviations (SD) higher cortical porosity and 0.6 SD lower trabecular BV/TV. Compact-appearing cortical porosity predicted fracture independent of aBMD; odds ratio (OR) = 1.92 (95% confidence interval [CI] 1.10–3.33). In women with osteoporosis at the UDR, cortical porosity did not distinguish those with fractures from those without because high porosity was present in 92% and 86% of each group, respectively. By contrast, in women with osteopenia at the UDR, high porosity of the compact-appearing cortex conferred an OR for fracture of 4.00 (95% CI 1.15–13.90). In women with osteoporosis, porosity is captured by aBMD, so measuring UDR cortical porosity does not improve diagnostic sensitivity. However, in women with osteopenia, cortical porosity was associated with forearm fractures.

Priming primary care physicians to treat osteoporosis after a fragility fracture: an integrated multidisciplinary approach

OBJECTIVE

To evaluate 2 incremental levels of intervention designed to increase initiation of osteoporosis treatment by primary care physicians (PCP) following fragility fractures (FF).

METHODS

Women and men over age 50 years were screened for incident FF in fracture clinics, and eligible outpatients were randomly assigned to standard care (SC) or to either minimal (MIN) or intensive (INT) interventions. The MIN and INT interventions were intended to educate and motivate both patients and PCP, but differed in their frequency of contact and information content. Delivery of osteoporosis medication was confirmed with pharmacists. Treatment rates were analyzed using an intention-to-treat approach.

RESULTS

At inclusion, 74.3% of 881 outpatients with FF were untreated. Followup at 12 months was completed in 92.3% of patients. Up to 90% of patients treated at inclusion remained treated at 12 months. Among patients who initially were untreated, 18.8% in the SC group, 40.4% in the MIN, and 53.2% in the INT groups were treated at 12 months. Change in treatment rates (adjusted for age and initial treatment) increased significantly after both MIN and INT. Only the INT intervention significantly increased treatment rates in patients with previous fractures. Negative predictors of change in treatment status included non-major FF, age younger than 65 years, and male sex.

CONCLUSION

Both interventions significantly increased initiation of osteoporosis treatment. Our multidisciplinary intervention builds on existing first-line structures and uses minimal specialized resources. Iterative and systematic interventions in the context of clinical care may modify the approach of PCP to osteoporosis management after FF and narrow the care gap in the long term.

Towards patient-specific material modeling of trabecular bone post-yield behavior

Bone diseases such as osteoporosis are one of the main causes of bone fracture and often result in hospitalization and long recovery periods. Researchers are aiming to develop new tools that consider the multiple determinants acting at the different scales of bone, and which can be used to clinically estimate patient-specific fracture risk and also assess the efficacy of new therapies. The main step towards this goal is a deep understanding of the bone organ, and is achieved by modeling the complexity of the structure and the high variability of the mechanical outcome. This review uses a hierarchical approach to evaluate bone mechanics at the macroscale, microscale, and nanoscale levels and the interactions between scales. The first section analyzes the experimental evidence of bone mechanics in the elastic and inelastic regions, microdamage generation, and post-yield toughening mechanisms from the organ level to the ultrastructural level. On the basis of these observations, the second section provides an overview of the constitutive models available to describe bone mechanics and predict patient-specific outcomes. Overall, the role of the hierarchical structure of bone and the interplay between each level is highlighted, and their effect is evaluated in terms of modeling biological variability and patient specificity.

FRAX and the assessment of the risk of developing a fragility fracture

Osteoporosis is common and the health and financial cost of fragility fractures is considerable. The burden of cardiovascular disease has been reduced dramatically by identifying and targeting those most at risk. A similar approach is potentially possible in the context of fragility fractures. The World Health Organization created and endorsed the use of FRAX, a fracture risk assessment tool, which uses selected risk factors to calculate a quantitative, patient-specific, ten-year risk of sustaining a fragility fracture. Treatment can thus be based on this as well as on measured bone mineral density. It may also be used to determine at-risk individuals, who should undergo bone densitometry. FRAX has been incorporated into the national osteoporosis guidelines of countries in the Americas, Europe, the Far East and Australasia. The United Kingdom National Institute for Health and Clinical Excellence also advocates its use in their guidance on the assessment of the risk of fragility fracture, and it may become an important tool to combat the health challenges posed by fragility fractures.

Cost-effective intervention thresholds against osteoporotic fractures based on FRAX® in Switzerland

FRAX-based cost-effective intervention thresholds in the Swiss setting were determined. Assuming a willingness to pay at 2× Gross Domestic Product per capita, an intervention aimed at reducing fracture risk in women and men with a 10-year probability for a major osteoporotic fracture at or above 15% is cost-effective.

INTRODUCTION

The fracture risk assessment algorithm FRAX® has been recently calibrated for Switzerland. The aim of the present analysis was to determine FRAX-based fracture probabilities at which intervention becomes cost-effective.

METHODS

A previously developed and validated state transition Markov cohort model was populated with Swiss epidemiological and cost input parameters. Cost-effective FRAX-based intervention thresholds (cost-effectiveness approach) and the cost-effectiveness of intervention with alendronate (original molecule) in subjects with a FRAX-based fracture risk equivalent to that of a woman with a prior fragility fracture and no other risk factor (translational approach) were calculated based on the Swiss FRAX model and assuming a willingness to pay of 2 times Gross Domestic Product per capita for one Quality-adjusted Life-Year.

RESULTS

In Swiss women and men aged 50 years and older, drug intervention aimed at decreasing fracture risk was cost-effective with a 10-year probability for a major osteoporotic fracture at or above 13.8% (range 10.8% to 15.0%) and 15.1% (range 9.9% to 19.9%), respectively. Age-dependent variations around these mean values were modest. Using the translational approach, treatment was cost-effective or cost-saving after the age 60 years in women and 55 in men who had previously sustained a fragility fracture. Using the latter approach leads to considerable underuse of the current potential for cost-effective interventions against fractures.

CONCLUSIONS

Using a FRAX-based intervention threshold of 15% for both women and men should permit cost-effective access to therapy to patients at high fracture probability based on clinical risk factors and thereby contribute to further reduce the growing burden of osteoporotic fractures in Switzerland.

General medical practitioners' knowledge and beliefs about osteoporosis and its investigation and management

This qualitative study explored beliefs and attitudes regarding osteoporosis and its management. General medical practitioners (GPs) were ambivalent about osteoporosis due to concern about financial barriers for patients and their own beliefs about the salience of osteoporosis. GPs considered investigation and treatment in the context of patients' whole lives.

PURPOSE

We aimed to investigate barriers, enablers, and other factors influencing the investigation and management of osteoporosis using a qualitative approach. This paper analyses data from discussions with general medical practitioners (GPs) about their beliefs and attitudes regarding osteoporosis and its management.

METHODS

Fourteen GPs and two practice nurses aged 27-89 years participated in four focus groups, from June 2010 to March 2011. Each group comprised 3-5 participants, and discussions were semi-structured, according to the protocol developed for the main study. Discussion points ranged from the circumstances under which GPs would initiate investigation for osteoporosis and their subsequent actions to their views about treatment efficacy and patient adherence to prescribed treatment. Audio recordings were transcribed and coded for analysis using analytic comparison to identify the major themes.

RESULTS

The GPs were not particularly concerned about osteoporosis in their patients or the general population, ranking diabetes, osteoarthritis, cardiovascular disease, and hypertension higher than concern about osteoporosis. They expressed confidence in the efficacy of anti-fracture medications but were concerned about the potential financial burden on patients with limited incomes. The GPs were unsure about guidelines for investigation and management of osteoporosis in men and the appropriate duration of treatment, particularly for the bisphosphonates in all patients.

CONCLUSIONS

The GPs' ambivalence about osteoporosis appeared to stem from structural factors such as financial barriers for patients and their own beliefs about the salience of osteoporosis. GPs considered the impact of investigating and prescribing treatment in the context of patients' whole lives.

Management of osteoporosis among the elderly with other chronic medical conditions

Osteoporosis is a highly prevalent chronic disease in the US and worldwide. The most serious consequence of this disorder is fractures, which have a serious negative impact on quality of life and are often the trigger for accelerated deterioration, ultimately ending in death. Despite the availability of effective preventive treatments, osteoporosis is frequently underdiagnosed and/or undertreated, particularly among the elderly, who are also at greatest risk. In addition, the presence of co-morbid medical conditions may be both a barrier to osteoporosis care and a risk factor for falls; thus individuals with multiple co-morbid conditions may be a particularly high-risk group. The management of osteoporosis involves improving bone health via adequate nutrition, calcium and vitamin D supplements, and fall prevention strategies. Although these measures are important in the management of all patients, most elderly patients are likely to need additional pharmacological therapy to adequately reduce their fracture risk. Several pharmacological treatments have been shown to significantly reduce the risk of fracture, including bisphosphonates (e.g. alendronate, risedronate, ibandronate, zoledronic acid), denosumab, raloxifene, calcitonin and teriparatide. Despite recent advances in osteoporosis care, additional action is urgently needed to improve the quality of life of osteoporotic patients in general and of elderly patients in particular, since fracture outcomes are typically poorer in older than in younger patients. This article reviews the current status of osteoporosis management, emphasizing the need to improve osteoporosis care, with a particular focus on the US, by the use of quality-improvement measures and incentives, which might result in an increased awareness and improved treatment for this debilitating disease.

Vertebral body bone strength: the contribution of individual trabecular element morphology

SUMMARY

Although the amount of bone explains the largest amount of variability in bone strength, there is still a significant proportion unaccounted for. The morphology of individual bone trabeculae explains a further proportion of the variability in bone strength and bone elements that contribute to bone strength depending on the direction of loading.

INTRODUCTION

Micro-CT imaging enables measurement of bone microarchitecture and subsequently mechanical strength of the same sample. It is possible using micro-CT data to perform morphometric analysis on individual rod and plate bone trabeculae using a volumetric spatial decomposition algorithm and hence determine their contribution to bone strength.

METHODS

Twelve pairs of vertebral bodies (T12/L1 or L4/L5) were harvested from human cadavers, and bone cubes (10 × 10 × 10 mm) were obtained. After micro-CT imaging, a volumetric spatial decomposition algorithm was applied, and measures of individual trabecular elements were obtained. Bone strength was measured in compression, where one bone specimen from each vertebral segment was tested supero-inferiorly (SI) and the paired specimen was tested antero-posteriorly (AP).

RESULTS

Bone volume fraction was the strongest individual determinant of SI strength (r(2) = 0.77, p < 0.0001) and AP (r(2) = 0.54, p < 0.0001). The determination of SI strength was improved to r(2) = 0.87 with the addition of mean rod length and relative plate bone volume fraction. The determination of AP strength was improved to r(2) = 0.85 with the addition of mean rod volume and relative rod bone volume fraction.

CONCLUSIONS

Microarchitectural measures of individual trabeculae that contribute to bone strength have been identified. In addition to the contribution of BV/TV, trabecular rod morphology increased the determination of AP strength by 57%, whereas measures of trabecular plate and rod morphology increased determination of SI strength by 13%. Decomposing vertebral body bone architecture into its constituent morphological elements shows that trabecular element morphology has specific functional roles to assist in maintaining skeletal integrity.

Osteo-cise: strong bones for life: protocol for a community-based randomised controlled trial of a multi-modal exercise and osteoporosis education program for older adults at risk of falls and fractures

Background

Osteoporosis affects over 220 million people worldwide, and currently there is no ‘cure’ for the disease. Thus, there is a need to develop evidence-based, safe and acceptable prevention strategies at the population level that target multiple risk factors for fragility fractures to reduce the health and economic burden of the condition.

Methods/design

The Osteo-cise: Strong Bones for Life study will investigate the effectiveness and feasibility of a multi-component targeted exercise, osteoporosis education/awareness and behavioural change program for improving bone health and muscle function and reducing falls risk in community-dwelling older adults at an increased risk of fracture. Men and women aged ≥60 years will participate in an 18-month randomised controlled trial comprising a 12-month structured and supervised community-based program and a 6-month ‘research to practise’ translational phase. Participants will be randomly assigned to either the Osteo-cise intervention or a self-management control group. The intervention will comprise a multi-modal exercise program incorporating high velocity progressive resistance training, moderate impact weight-bearing exercise and high challenging balance exercises performed three times weekly at local community-based fitness centres. A behavioural change program will be used to enhance exercise adoption and adherence to the program. Community-based osteoporosis education seminars will be conducted to improve participant knowledge and understanding of the risk factors and preventative measures for osteoporosis, falls and fractures. The primary outcomes measures, to be collected at baseline, 6, 12, and 18 months, will include DXA-derived hip and spine bone mineral density measurements and functional muscle power (timed stair-climb test). Secondary outcomes measures include: MRI-assessed distal femur and proximal tibia trabecular bone micro-architecture, lower limb and back maximal muscle strength, balance and function (four square step test, functional reach test, timed up-and-go test and 30-second sit-to-stand), falls incidence and health-related quality of life. Cost-effectiveness will also be assessed.

Discussion

The findings from the Osteo-cise: Strong Bones for Life study will provide new information on the efficacy of a targeted multi-modal community-based exercise program incorporating high velocity resistance training, together with an osteoporosis education and behavioural change program for improving multiple risk factors for falls and fracture in older adults at risk of fragility fracture.

Trial registration

Australian New Zealand Clinical Trials Registry reference ACTRN12609000100291

Cross-sectional analysis of association between socioeconomic status and utilization of primary total hip joint replacements 2006-7: Australian Orthopaedic Association National Joint Replacement Registry

BACKGROUND

The utilization of total hip replacement (THR) surgery is rapidly increasing, however few data examine whether these procedures are associated with socioeconomic status (SES) within Australia. This study examined primary THR across SES for both genders for the Barwon Statistical Division (BSD) of Victoria, Australia.

METHODS

Using the Australian Orthopaedic Association National Joint Replacement Registry data for 2006-7, primary THR with a diagnosis of osteoarthritis (OA) among residents of the BSD was ascertained. The Index of Relative Socioeconomic Disadvantage was used to measure SES; determined by matching residential addresses with Australian Bureau of Statistics census data. The data were categorised into quintiles; quintile 1 indicating the most disadvantaged. Age- and sex-specific rates of primary THR per 1,000 person years were reported for 10-year age bands using the total population at risk.

RESULTS

Females accounted for 46.9% of the 642 primary THR performed during 2006-7. THR utilization per 1,000 person years was 1.9 for males and 1.5 for females. The highest utilization of primary THR was observed in those aged 70-79 years (males 6.1, and females 5.4 per 1,000 person years). Overall, the U-shaped pattern of THR across SES gave the appearance of bimodality for both males and females, whereby rates were greater for both the most disadvantaged and least disadvantaged groups.

CONCLUSIONS

Further work on a larger scale is required to determine whether relationships between SES and THR utilization for the diagnosis of OA is attributable to lifestyle factors related to SES, or alternatively reflects geographic and health system biases. Identifying contributing factors associated with SES may enhance resource planning and enable more effective and focussed preventive strategies for hip OA.

Imaging the femoral cortex: thickness, density and mass from clinical CT

There is growing evidence that focal thinning of cortical bone in the proximal femur may predispose a hip to fracture. Detecting such defects in clinical CT is challenging, since cortices may be significantly thinner than the imaging system's point spread function. We recently proposed a model-fitting technique to measure sub-millimetre cortices, an ill-posed problem which was regularized by assuming a specific, fixed value for the cortical density. In this paper, we develop the work further by proposing and evaluating a more rigorous method for estimating the constant cortical density, and extend the paradigm to encompass the mapping of cortical mass (mineral mg/cm(2)) in addition to thickness. Density, thickness and mass estimates are evaluated on sixteen cadaveric femurs, with high resolution measurements from a micro-CT scanner providing the gold standard. The results demonstrate robust, accurate measurement of peak cortical density and cortical mass. Cortical thickness errors are confined to regions of thin cortex and are bounded by the extent to which the local density deviates from the peak, averaging 20% for 0.5mm cortex.

The pathogenesis, diagnosis, investigation and management of osteoporosis

With an increasingly ageing population, osteoporosis and osteoporosis-related fractures is fast becoming an important public health problem placing a considerable economic burden on health service resources. This does not account for the substantial pain, disability and indeed mortality incurred after a fracture, particularly a hip fracture. Osteoporosis is a systemic skeletal disorder which results from an imbalance in bone remodeling. This leads to a reduction in bone strength and increased susceptibility to fracture. It affects up to 1 in 2 women and 1 in 5 men. In the past 2 decades, there have been significant advances in bone biology which have helped in the understanding of the pathogenesis of osteoporosis and have led to improved therapies. In developing strategies for fracture prevention, it is important to identify those individuals with the highest fracture risk who will require pharmacological intervention. Treatment is aimed at fracture prevention and includes modification of general lifestyle factors which have been linked to fractures in epidemiological studies and ensuring optimum calcium and vitamin D intake as adjunct to active anti-fracture therapy. A number of drugs are now approved for the treatment of osteoporosis. This review article will describe the pathogenesis of osteoporosis and focus on the methods currently in use for the identification of patients at high fracture risk and will highlight their usefulness and limitations. The existing anti-fracture pharmacotherapies and those in development will be reviewed. Assessment of their effectiveness including the use of biochemical markers of bone turnover in this clinical context will be reviewed.

Similarities in acquired factors related to postmenopausal osteoporosis and sarcopenia

Postmenopausal population is at increased risk of musculoskeletal impairments. Sarcopenia and osteoporosis are associated with significant morbidity and social and health-care costs. These two conditions are uniquely linked with similarities in pathophysiology and diagnostic methods. Uniform diagnostic criteria for sarcopenia are still evolving. Postmenopausal sarcopenia and osteoporosis share many environmental risk- and preventive factors. Moreover, geriatric frailty syndrome may result from interaction of osteoporosis and sarcopenia and may lead to increased mortality. The present paper reviews the factors in evolution of postmenopausal sarcopenia and osteoporosis.

Use of strontium as a treatment method for osteoporosis

Given its increasing incidence and serious complications, osteoporosis requires safe and effective long-term treatment. Strontium ranelate (SR), a new anti-osteoporotic treatment with a unique mode of action, has been investigated in the SOTI (Spinal Osteoporosis Therapeutic Intervention) and the TROPOS (Treatment of Peripheral Osteoporosis) trials, two major 3-year multinational placebo-controlled phase 3 randomized clinical trials. Unlike antiresorptive agents, SR produced steady and significant bone mineral density increases that correlated directly with decreases in vertebral and hip fracture risk. The safety profile of SR was almost similar to placebo in both trials. A slight but significant increased risk of thromboembolism events was noted from the pooled phase 3 studies data. However, this increased was not found in a large retrospective observational study. Thus, SR demonstrates broad spectrum safety and efficacy in reducing the risks of both vertebral and nonvertebral (including hip) fractures in a wide variety of patients, and should be considered as a first-line option to treat women at risk of osteoporotic fractures, whatever their age, the severity of the disease, and their risk factors.

Treatment of Postmenopausal Osteoporosis: Focus on Strontium Ranelate

Given its increasing incidence and serious complications, osteoporosis requires safe and effective long-term treatment. Strontium ranelate (SR), a new anti-osteoporotic treatment with a unique mode of action, has been investigated in the Spinal Osteoporosis Therapeutic Intervention (SOTI) and the Treatment Of Peripheral OSteoporosis (TROPOS) trials, two major 3-year multinational placebo-controlled Phase III randomized clinical trials. In SOTI, SR treatment reduced the risk of vertebral fracture by 41% (20.9% vs. 32.8%, P < 0.001); in TROPOS, it reduced the risk of non-vertebral fracture by 16% (11.2% vs. 12.9%, P = 0.04), and the risk of hip fracture in patients at high risk by 36% (4.3% vs. 6.4%, P = 0.046). Also SR has been shown to decrease the risk of vertebral fracture after 4 years of treatment and the risk of nonvertebral fracture after 5 years. Also it demonstrated for high risk patients a significant decrease of the risk of hip fractures (–43%) after 5 years of treatment. Unlike antiresorptive agents, SR produced steady and significant BMD increases that correlated directly with decreases in vertebral and hip fracture risk. Preplanned analysis of the pooled dataset from SOTI and TROPOS showed that SR was effective whether or not patients had key risk factors for fractures at baseline. SR was also effective in patients with osteopenia and younger postmenopausal patients aged 50–65 years. It was also effective for preventing both vertebral and nonvertebral fractures in the elderly (>80 years). Also, SR significantly attenuated height loss and decreased back pain. Finally long-term follow-up showed that BMD gains were maintained through a 8 year-period with maintaining the incidence of fracture between the first 3 years and the last 3 years of treatment. The safety profile of SR was almost similar to placebo in both trials. A slight but significant increased risk of thromboembolism events was noted from the pooled phase III studies data. However this increased was not found in a large retrospective observational study. Thus, SR demonstrates broad spectrum safety and efficacy in reducing the risks of both vertebral and non-vertebral (including hip) fractures in a wide variety of patients, and should be considered as a first-line option to treat women at risk of osteoporotic fractures, whatever their age, the severity of the disease, and their risk factors.

Collagen mutation causes changes of the microdamage morphology in bone of an OI mouse model

Previous studies have postulated that ultrastructural changes may alter the pattern and capacity of microdamage accumulation in bone. Using an osteogenesis imperfecta (OI) mouse model, this study was performed to investigate the correlation of collagen mutation with the microdamage morphology and the associated brittleness of bone. In this study, femurs from mild OI and wild type mice were fatigued under four-point bending to create microdamage in the specimens. Then, the microdamage morphology of these specimens was examined using the bulk-staining technique with basic fuchsin. Similar with the results of previous studies, it was observed that linear microcracks were formed more easily in compression, whereas diffuse damage was induced more readily in tension for both wild-type and mild-type mice. However, less diffuse damage was found in the tensile side of mild OI mouse femurs (collagen mutation) compared with those of wild type mice, showing that the microdamage morphology is correlated to the brittleness of bone. The results of this study provide direct evidence that supports the prediction made by the previous numerical simulation studies, suggesting that microdamage morphology in bone is significantly correlated with the integrity of the collagen phase.

Vertebral fracture

Vertebral fractures are usually the first to occur in osteoporosis, provide indisputable evidence of reduced bone strength, and are frequently a harbinger of further vertebral and nonvertebral fracture. Radiologists are best placed to draw attention to the presence of vertebral fractures, most of which are clinically silent. Magnetic resonance imaging supplemented if necessary by computed tomography is usually sufficient to enable distinction between osteoporotic and non-osteoporotic vertebral fracture, without a need for percutaneous biopsy.

Prognosis of fracture: evaluation of predictive accuracy of the FRAX algorithm and Garvan nomogram

We evaluated the prognostic accuracy of fracture risk assessment tool (FRAX) and Garvan algorithms in an independent Australian cohort. The results suggest comparable performance in women but relatively poor fracture risk discrimination in men by FRAX. These data emphasize the importance of external validation before widespread clinical implementation of prognostic tools in different cohorts.

INTRODUCTION

Absolute risk assessment is now recognized as a preferred approach to guide treatment decision. The present study sought to evaluate accuracy of the FRAX and Garvan algorithms for predicting absolute risk of osteoporotic fracture (hip, spine, humerus, or wrist), defined as major in FRAX, in a clinical setting in Australia.

METHODS

A retrospective validation study was conducted in 144 women (69 fractures and 75 controls) and 56 men (31 fractures and 25 controls) aged between 60 and 90 years. Relevant clinical data prior to fracture event were ascertained. Based on these variables, predicted 10-year probabilities of major fracture were calculated from the Garvan and FRAX algorithms, using US (FRAX-US) and UK databases (FRAX-UK). Area under the receiver operating characteristic curves (AUC) was computed for each model.

RESULTS

In women, the average 10-year probability of major fracture was consistently higher in the fracture than in the nonfracture group: Garvan (0.33 vs. 0.15), FRAX-US (0.30 vs. 0.19), and FRAX-UK (0.17 vs. 0.10). In men, although the Garvan model yielded higher average probability of major fracture in the fracture group (0.32 vs. 0.14), the FRAX algorithm did not: FRAX-US (0.17 vs. 0.19) and FRAX-UK (0.09 vs. 0.12). In women, AUC for the Garvan, FRAX-US, and FRAX-UK algorithms were 0.84, 0.77, and 0.78, respectively, vs. 0.76, 0.54, and 0.57, respectively, in men.

CONCLUSION

In this analysis, although both approaches were reasonably accurate in women, FRAX discriminated fracture risk poorly in men. These data support the concept that all algorithms need external validation before clinical implementation.

Socioeconomic status and bone mineral density in a population-based sample of men

Overall, socioeconomic status (SES) is inversely associated with poorer health outcomes. However, current literature provides conflicting data of the relationship between SES and bone mineral density (BMD) in men. In an age-stratified population-based randomly selected cross-sectional study of men (n=1467) we assessed the association between SES and lifestyle exposures in relation to BMD. SES was determined by matching the residential address for each subject with Australian Bureau of Statistics 2006 census data for the study region. BMD was measured at the spine and femoral neck by dual energy X-ray absorptiometry. Lifestyle variables were collected by self-report. Regression models were age-stratified into younger and older groups and adjusted for age, weight, dietary calcium, physical activity, and medications known to affect bone. Subjects with spinal abnormalities were excluded from analyses of BMD at the spine. In younger men, BMD was highest at the spine in the mid quintiles of SES, where differences were observed compared to quintile 1 (1-7%, p<0.05). In older men, the pattern of BMD across SES quintiles was reversed, and subjects from mid quintiles had the lowest BMD, with differences observed compared to quintile 5 (1-7%, p<0.05). Differences in BMD at the spine across SES quintiles represent a potential 1.5-fold increase in fracture risk for those with the lowest BMD. There were no differences in BMD at the femoral neck. Further research is warranted which examines the mechanisms that may underpin differences in BMD across SES quintiles and to address the current paucity of data in this field of enquiry.

Bone turnover markers and prediction of fracture: a prospective follow-up study of 1040 elderly women for a mean of 9 years

Osteoporosis is characterized by compromised bone mass and strength, predisposing to an increased risk of fracture. Increased bone metabolism has been suggested to be a risk factor for fracture. The aim of this study was to evaluate whether baseline bone turnover markers are associated with long-term incidence of fracture in a population-based sample of 1040 women who were 75 years old (Malmö OPRA study). Seven bone markers (S-TRACP5b, S-CTX-I, S-OC[1-49], S-TotalOC, S-cOC, S-boneALP, and urinary osteocalcin) were measured at baseline and 1-year follow-up visit. During the mean follow-up of 9.0 years (range 7.4-10.9), 363 women sustained at least one fracture of any type, including 116 hip fractures and 103 clinical vertebral fractures. High S-TRACP5b and S-CTX-I levels were associated with increased risk of any fracture with hazard ratios [HRs (95% confidence interval)] of 1.16 (1.04-1.29) and 1.13 (1.01-1.27) per SD increase, respectively. They also were associated with increased risk of clinical vertebral fracture with HRs of 1.22 (1.01-1.48) and 1.32 (1.05-1.67), respectively. Markers were not associated with risk for hip fracture. Results were similar when we used resorption markers, including urinary osteocalcin, measured at the 1-year visit or an average of the two measurements. The HRs were highest for any fracture in the beginning of the follow-up period, 2.5 years from baseline. For vertebral fractures, the association was more pronounced and lasted for a longer period of time, at least for 5 years. In conclusion, elevated levels of S-TRACP5b, S-CTX-I, and urinary osteocalcin are associated with increased fracture risk for up to a decade in elderly women.

High resolution cortical bone thickness measurement from clinical CT data

The distribution of cortical bone in the proximal femur is believed to be a critical component in determining fracture resistance. Current CT technology is limited in its ability to measure cortical thickness, especially in the sub-millimetre range which lies within the point spread function of today’s clinical scanners. In this paper, we present a novel technique that is capable of producing unbiased thickness estimates down to 0.3 mm. The technique relies on a mathematical model of the anatomy and the imaging system, which is fitted to the data at a large number of sites around the proximal femur, producing around 17,000 independent thickness estimates per specimen. In a series of experiments on 16 cadaveric femurs, estimation errors were measured as −0.01 ± 0.58 mm (mean ± 1 std.dev.) for cortical thicknesses in the range 0.3–4 mm. This compares with 0.25 ± 0.69 mm for simple thresholding and 0.90 ± 0.92 mm for a variant of the 50% relative threshold method. In the clinically relevant sub-millimetre range, thresholding increasingly fails to detect the cortex at all, whereas the new technique continues to perform well. The many cortical thickness estimates can be displayed as a colour map painted onto the femoral surface. Computation of the surfaces and colour maps is largely automatic, requiring around 15 min on a modest laptop computer.

2008 Santa Fe Bone Symposium: update on osteoporosis

The Ninth Annual Santa Fe Bone Symposium was held on August 1-2, 2008, in Santa Fe, New Mexico, USA. The symposium faculty presented the current best evidence on selected topics of clinical relevance in the fields of osteoporosis, metabolic bone disease, and assessment of skeletal health. The educational venues were in the form of didactic presentations, panel discussions, challenging cases, and numerous interactive discussions. Knowledge of basic science and clinical trials was applied to real-world patient scenarios that were discussed by faculty experts and clinician participants. Topics included an update on the rationale and development of new agents for the treatment of osteoporosis, the use of bone turnover markers in clinical practice, hospital-based pathways for the management of hip fracture patients, injectable bisphosphonates for the treatment of osteoporosis, combination therapy with anabolic and antiresorptive agents, and assessment of skeletal health with devices other than central dual-energy X-ray absorptiometry. This is a collection of scientific essays based on presentations and discussions at the 2008 Santa Fe Bone Symposium.