Premenopausal women with a distal radial fracture have deteriorated trabecular bone density and morphology compared with controls without a fracture

Opportunistic hand radiographs to screen for low forearm bone mineral density: a prospective and retrospective cohort study

BACKGROUND

Low bone mineral density affects 53% of women over age 65 in the US, yet many are unaware and remain untreated. Underdiagnosis of forearm osteoporosis and related fragility fractures represent missed warning signs of more deadly, future fractures. This study aimed to determine if hand radiographs could serve as early, simple screening tools for predicting low forearm bone mineral density (BMD).

METHODS

We evaluated posterior-anterior (PA) hand radiographs (x-rays) and Dual-energy X-ray absorptiometry (DXA) scans of 43 participants. The ratio of the intramedullary cavity to total cortical diameter of the second metacarpal (second metacarpal cortical percentage (2MCP)) was used as a potential diagnostic marker. Mixed-effects linear regression was performed to determine correlation of 2MCP with BMD from various anatomic regions. Repeated measures ANOVAs were used to compare BMD across sites. An optimal 2MCP cutoff for predicting forearm osteopenia and osteoporosis was found using Receiver Operating Curves.

RESULTS

2MCP is directly correlated with BMD in the forearm. The optimal 2MCP of 48.3% had 80% sensitivity for detecting osteoporosis of the 1/3 distal forearm. An 2MCP cutoff of 50.8% had 84% sensitivity to detect osteoporosis of the most distal forearm. Both 2MCP cutoffs were more sensitive at predicting forearm osteoporosis than femoral neck T-scores.

CONCLUSIONS

These findings support the expansion of osteoporosis screening to include low-cost hand x-rays, aiming to increase diagnosis and treatment of low forearm BMD and fractures. Proposed next steps include confirming the optimal 2MCP cutoff at scale and integrating automatic 2MCP measurements into PAC systems.

Motion grading of high-resolution quantitative computed tomography supported by deep convolutional neural networks

Image quality degradation due to subject motion confounds the precision and reproducibility of measurements of bone density, morphology and mechanical properties from high-resolution peripheral quantitative computed tomography (HR-pQCT). Time-consuming operator-based scoring of motion artefacts remains the gold standard to determine the degree of acceptable motion. However, due to the subjectiveness of manual grading, HR-pQCT scans of poor quality, which cannot be used for analysis, may be accepted upon initial review, leaving patients with incomplete or inaccurate imaging results. Convolutional Neural Networks (CNNs) enable fast image analysis with relatively few pre-processing requirements in an operator-independent and fully automated way for image classification tasks. This study aimed to develop a CNN that can predict motion scores from HR-pQCT images, while also being aware of uncertain predictions that require manual confirmation. The CNN calculated motion scores within seconds and achieved a high F1-score (86.8 ± 2.8 %), with good precision (87.5 ± 2.7 %), recall (86.7 ± 2.9 %) and a substantial agreement with the ground truth measured by Cohen's kappa (κ = 68.6 ± 6.2 %); motion scores of the test dataset were predicted by the algorithm with comparable accuracy, precision, sensitivity and agreement as by the operators (p > 0.05). This post-processing approach may be used to assess the effect of motion scores on microstructural analysis and can be immediately implemented into clinical protocols, significantly reducing the time for quality assessment and control of HR-pQCT scans.

The clinician's guide to prevention and treatment of osteoporosis

Osteoporosis is the most common metabolic bone disease in the USA and the world. It is a subclinical condition until complicated by fracture(s). These fractures place an enormous medical and personal burden on individuals who suffer from them and take a significant economic toll. Any new fracture in an adult aged 50 years or older signifies imminent elevated risk for subsequent fractures, particularly in the year following the initial fracture. What a patient perceives as an unfortunate accident may be seen as a sentinel event indicative of bone fragility and increased future fracture risk even when the result of considerable trauma. Clinical or subclinical vertebral fractures, the most common type of osteoporotic fractures, are associated with a 5-fold increased risk for additional vertebral fractures and a 2- to 3-fold increased risk for fractures at other sites. Untreated osteoporosis can lead to a vicious cycle of recurrent fracture(s), often resulting in disability and premature death. In appropriate patients, treatment with effective antifracture medication prevents fractures and improves outcomes. Primary care providers and medical specialists are critical gatekeepers who can identify fractures and initiate proven osteoporosis interventions. Osteoporosis detection, diagnosis, and treatment should be routine practice in all adult healthcare settings. The Bone Health and Osteoporosis Foundation (BHOF) - formerly the National Osteoporosis Foundation - first published the Clinician's Guide in 1999 to provide accurate information on osteoporosis prevention and treatment. Since that time, significant improvements have been made in diagnostic technologies and treatments for osteoporosis. Despite these advances, a disturbing gap persists in patient care. At-risk patients are often not screened to establish fracture probability and not educated about fracture prevention. Most concerning, the majority of highest risk women and men who have a fracture(s) are not diagnosed and do not receive effective, FDA-approved therapies. Even those prescribed appropriate therapy are unlikely to take the medication as prescribed. The Clinician's Guide offers concise recommendations regarding prevention, risk assessment, diagnosis, and treatment of osteoporosis in postmenopausal women and men aged 50 years and older. It includes indications for bone densitometry as well as fracture risk thresholds for pharmacologic intervention. Current medications build bone and/or decrease bone breakdown and dramatically reduce incident fractures. All antifracture therapeutics treat but do not cure the disease. Skeletal deterioration resumes sooner or later when a medication is discontinued-sooner for nonbisphosphonates and later for bisphosphonates. Even if normal BMD is achieved, osteoporosis and elevated risk for fracture are still present. The diagnosis of osteoporosis persists even if subsequent DXA T-scores are above - 2.5. Ongoing monitoring and strategic interventions will be necessary if fractures are to be avoided. In addition to pharmacotherapy, adequate intake of calcium and vitamin D, avoidance of smoking and excessive alcohol intake, weight-bearing and resistance-training exercise, and fall prevention are included in the fracture prevention armamentarium. Where possible, recommendations in this guide are based on evidence from RCTs; however, relevant published data and guidance from expert clinical experience provides the basis for recommendations in those areas where RCT evidence is currently deficient or not applicable to the many osteoporosis patients not considered for RCT participation due to age and morbidity.

Prolonged Operative Time Associated with Increased Healthcare Utilization after Open Reduction and Internal Fixation of Intra-Articular and Extra-Articular Distal Radial Fractures: An Analysis of 17,482 Cases

Background  The current literature does not contain a quantitative description of the associations between operative time and adverse outcomes after open reduction and internal fixation (ORIF) of distal radial fractures (DRF). Questions/Purpose  We aimed to quantify associations between DRF ORIF operative time and 1) 30-day postoperative health care utilization and 2) the incidence of local wound complications. Methods  The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was queried for DRF ORIF cases (January 2012-December 2018). A total of 17,482 cases were identified. Primary outcomes included health care utilization (length of stay [LOS], discharge dispositions, 30-day readmissions, and reoperations) per operative-time category. Secondary outcome was incidence of wound complications per operative-time category. Multivariate regression was conducted to determine operative-time categories associated with increased risk while adjusting for demographics, comorbidities, and fracture type. Spline regression models were constructed to visualize associations. Results  The 121 to 140-minute category was associated with significantly higher risk of a LOS > 2 days (odds ration [OR]: 1.64; 95% confidence interval [CI]:1.1-2.45; p  = 0.014) and nonhome discharge (OR: 1.72; 95% CI:1.09-2.72; p  = 0.02) versus 41 to 60-minute category. The ≥ 180-minute category exhibited highest odds of LOS > 2 days (OR: 2.08; 95%CI: 1.33-3.26; p  = 0.001), nonhome discharge disposition (OR: 1.87; 95% CI: 1.05-3.33; p  = 0.035), and 30-day reoperation occurrence (OR: 3.52; 95% CI: 1.59-7.79; p  = 0.002). There was no association between operative time and 30-day readmission ( p  > 0.05 each). Higher odds of any-wound complication was first detected at 81 to 100-minute category (OR: 3.02; 95% CI: 1.08-8.4; p  = 0.035) and peaked ≥ 181 minutes (OR: 9.62; 95% CI: 2.57-36.0; p  = 0.001). Spline regression demonstrated no increase in risk of adverse outcomes if operative times were 50 minutes or less. Conclusion  Our findings demonstrate that prolonged operative time is correlated with increased odds of health care utilization and wound complications after DRF ORIF. Operative times greater than 60 minutes seem to carry higher odds of postoperative complications.

Longitudinal Changes in Serum Markers of Bone Metabolism and Bone Material Strength in Premenopausal Women with Distal Radial Fracture

BACKGROUND

Markers of bone metabolism (MBM) play an important role in fracture evaluation, and changes have been associated with increased fracture risk. The purpose of the present study was to describe changes in MBM in premenopausal women with distal radial fractures.

METHODS

Premenopausal women with distal radial fractures (n = 34) and without fractures (controls) (n = 39) were recruited. Serum MBM in patients with distal radial fractures were obtained at the time of the initial presentation, 6 weeks, and 3, 6, and 12 months. MBM included 25(OH) vitamin D, PTH, osteocalcin, P1NP, BSAP, CTX, sclerostin, DKK1, periostin, and TRAP5b. Areal bone mineral density (aBMD) was assessed with dual x-ray absorptiometry, and the bone material strength index (BMSi) was assessed with microindentation.

RESULTS

Most MBM reached peak levels at 6 weeks after the injury, including osteocalcin (+17.7%), sclerostin (+23.5%), and DKK1 (12.6%). Sclerostin was lower (-27.4%) and DKK1 was higher (+22.2%) at 1 year after the fracture. CTX declined below baseline levels at 6 and 12 months, whereas TRAP5b, BSAP, and periostin did not significantly change. At 12 months, sclerostin was lower (p = 0.003) and DKK1 was higher (p = 0.03) in the distal radial fracture group than in the control group. Greater fracture severity was associated with greater increases in P1NP and BSAP. aBMD and BMSi were not associated with fracture.

CONCLUSIONS

Distal radial fractures caused increases in several MBM, which typically peaked at 6 weeks after injury and gradually decreased over 6 months. Sclerostin and DKK1 remained below and above baseline at 1 year, respectively. Increasing fracture severity resulted in larger changes in MBM. aBMD and BMSi did not discriminate between patients with distal radial fractures and controls. Continued efforts to identify markers of skeletal fragility in young women are warranted to mitigate future fracture risk.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Longitudinal Analysis of Circulating Markers of Bone Turnover Across Multiple Decades in Osteoporotic Women

PURPOSE

The objective of this study was to analyze changes in serum markers of bone turnover across multiple decades in osteoporotic women compared with nonosteoporotic controls, to determine their utility as potential predictors for osteoporosis. Early prediction of those at risk for osteoporosis can enable early intervention before the irreversible loss of critical bone mass.

METHODS

Serum samples were obtained from 20 women given the diagnosis of osteoporosis after age 46 years and 20 age-matched women with normal bone mineral density from 4 time points in their life (ages 25-31, 32-38, 39-45, and 46-60 years). Serum levels of bone turnover markers (propeptide of type I collagen, parathyroid hormone, bone-specific alkaline phosphatase, osteocalcin, C-terminal telopeptide of type I collagen, sclerostin, osteoprotegerin, osteopontin, and 25-OH vitamin D) were measured using commercially available arrays and kits. We used logistic regression to assess these individual serum markers as potential predictors of osteoporosis, and mixed-effects modeling to assess the change in bone turnover markers between osteoporotic and control groups over time, then performed fivefold cross-validation to assess the classification ability of the models.

RESULTS

Markers of bone turnover, bone-specific alkaline phosphatase, C-terminal telopeptide of type I collagen, sclerostin, and osteocalcin were all independent predictors at multiple time points; osteopontin was an independent predictor in the 39- to 45-year age group. Receiver operating characteristic analyses demonstrated moderately strong classification ability at all time points. Sclerostin levels among groups diverged over time and were higher in the control group than the osteoporotic group, with significant differences observed at time points 3 and 4.

CONCLUSIONS

Serum markers of bone turnover may be used to estimate the likelihood of osteoporosis development in individuals over time. Although prospective validation is necessary before recommending widespread clinical use, this information may be used to identify patients at risk for developing low bone mineral density long before traditional screening would ostensibly take place.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic II.

Dairy Food Intake Is Not Associated with Measures of Bone Microarchitecture in Men and Women: The Framingham Osteoporosis Study

Previous studies reported that dairy foods are associated with higher areal bone mineral density (BMD) in older adults. However, data on bone strength and bone microarchitecture are lacking. We determined the association of dairy food intake (milk, yogurt, cheese, milk + yogurt, and milk + yogurt + cheese, servings/week) with high resolution peripheral quantitative computed tomography (HR-pQCT) measures of bone (failure load, cortical BMD, cortical thickness, trabecular BMD, and trabecular number). This cross-sectional study included participants with diet from a food frequency questionnaire (in 2005–2008 and/or 1998–2001) and measurements of cortical and trabecular BMD and microarchitecture at the distal tibia and radius (from HR-pQCT in 2012–2015). Sex-specific multivariable linear regression estimated the association of dairy food intake (energy adjusted) with each bone measure adjusting for covariates. Mean age was 64 (SD 8) years and total milk + yogurt + cheese intake was 10.0 (SD 6.6) and 10.6 (6.4) servings/week in men and women, respectively. No significant associations were observed for any of the dairy foods and bone microarchitecture measures except for cheese intake, which was inversely associated with cortical BMD at the radius (p = 0.001) and tibia (p = 0.002) in women alone. In this cohort of primarily healthy older men and women, dairy intake was not associated with bone microarchitecture. The findings related to cheese intake and bone microarchitecture in women warrant further investigation.

Three-dimensional characterization of trabecular bone mineral density of the proximal ulna using quantitative computed tomography

BACKGROUND

Although previous studies have measured general proximal forearm bone mineral density (BMD), no study has systematically mapped the 3-dimensional trabecular BMD of the proximal ulna. The aim of this study was to describe the 3-dimensional distribution of the trabecular bone density of the proximal ulna. We hypothesize a variable distribution of proximal ulna trabecular BMD depending on the region of interest (ROI).

METHODS

Computed tomographic (CT) scans of 9 fresh-frozen cadaveric proximal ulna specimens with a mean age of 59.3 ± 8.1 years were studied. Each CT file was converted from DICOM to a QCT file that could be analyzed using QCT software (QCT Pro Version 6.1, Model 4 CT Calibration Phantom; MindWays Software Inc, Austin, TX, USA). The ROIs were defined as spheres of trabecular bone 3 mm in diameter located throughout the proximal ulna.

RESULTS

ROIs proximal to the trochlear notch demonstrated higher BMD than ROIs distal to the trochlear notch. Furthermore, volar ROIs adjacent to the ulnohumeral joint tended to have higher BMD than dorsal ROIs. The highest BMD was found in the tip of the olecranon.

CONCLUSION

Hardware in fixation constructs for proximal ulnar fractures should be directed toward ROIs with the highest BMD to maximize purchase. Hardware should approach the ulnohumeral joint without penetrating the joint to capture trabecular bone with the highest BMD. The most important fixation in such a construct will be that which captures trabecular bone with maximum BMD proximal to the trochlear notch (eg, the tip of the olecranon).

Changes in fall risk and functional status in women aged 50 years and older after distal radius fracture: A prospective 1-year follow-up study

STUDY DESIGN

Prospective cohort study.

INTRODUCTION

Few studies have evaluated the course of recovery after distal radius fracture (DRF) when functional decline and fracture risk may be affected.

PURPOSE OF THE STUDY

The purpose of this study was to determine changes in overall functional status over the first year after a DRF in women aged 50 years and older.

METHODS

Seventy-eight women were assessed for balance, balance confidence, lower extremity strength, gait speed, fall history, physical activity levels, and self-reported wrist pain and function (Patient-Rated Wrist Evaluation) at weeks 1, 3, 9, 12, 26, and 52 after DRF. Descriptive data were generated for all variables; a 3-way mixed analysis of variance with repeated measures was used to compare differences between participants aged 50-65 years and 65 years and older.

RESULTS

There was a significant improvement in functional status measures for both age categories except single-leg balance and fast gait speed, from 1 week after fracture extending up to 1 year after fracture (ranging from 6.1% improvement to 25% improvement, P < .05). There was no significant time × age interaction, as both age groups had the same pattern of recovery; however, there was significantly lower functional status in the older group across all time points.

CONCLUSION

Regardless of age, monitoring and addressing functional status including upper limb function, overall strength, balance, confidence, usual gait speed, and physical activity right up to 1 year after fracture is an important consideration for clinicians treating women recovering from DRF. Given the high future fracture risk for these women, identifying functional recovery patterns can help to direct future research and determine preventative strategies.

Three-Dimensional Characterization of Trabecular Bone Mineral Density of the Distal Radius Utilizing Quantitative Computed Tomography

Background: Distal radius (DR) fractures demonstrate patterns of predictable fragments. Bone mineral density (BMD) measurements of these regions of interest (ROIs) may guide more precise treatment. Methods: Computed tomography (CT) scans of the DR of 42 healthy volunteers (23 female) were analyzed using quantitative CT software, measuring BMD within trabecular bone. Seven ROIs were described by alignment with the distal (volar ulnar distal [VUD], dorsal ulnar distal [DUD], volar radial distal [VRD], and dorsal radial distal [DRD]) or proximal (middle ulnar proximal [MUP], middle proximal [MP], and middle radial proximal [MRP]) sigmoid notch. Additional ROIs were the radial styloid (RS) and metadiaphysis (MD). A general estimation equation assessed subject's BMDs with predictive factors of gender, ROI, and age. The interaction between gender, ROI, and age was included in the model to allow for differences in ROI to vary with gender and/or age. Results: Comparing ROIs within the same gender and, separately, within the same age group revealed significantly higher BMD adjacent to the radioulnar and radiocarpal joints. Male and female individuals aged ≥50 years (mean: 172.7 mg/cm³ ± 6.1) had significantly lower BMD than those aged <50 years (mean: 202.7 mg/cm³ ± 5.8) when all ROIs were considered. Males had higher mean BMD at each ROI compared with females; these differences were significant in 5 of the 9 ROIs: VUD, DUD, DRD, RS, MUP. Conclusions: Trabecular BMD of the DR is highest adjacent to the radioulnar and radiocarpal joints. Female patients and those ≥50 years have lower trabecular BMD.

Utility of Distal Forearm DXA as a Screening Tool for Primary Osteoporotic Fragility Fractures of the Distal Radius: A Case-Control Study

BACKGROUND

Osteoporotic fragility fractures frequently occur at the distal part of the radius. This suggests that initial osteoporosis evaluation at this site may inform screening and treatment to prevent additional fractures. The purpose of this study was to investigate the utility of distal forearm dual x-ray absorptiometry (DXA) as a screening tool to assess the risk of fragility fractures at the distal part of the radius.

METHODS

This retrospective, case-control study included postmenopausal women who had sustained a distal radial fracture (fracture group, n = 110) and postmenopausal women with no history of fracture (control group, n = 95). DXA measurements at the spine, hip, and distal part of the forearm (ultra-distal, mid-distal, and one-third distal sections) were compared between the groups on the basis of bone mineral density (BMD), T-score, and the proportion of patients with a T-score of ≤-2.5 standard deviations (SD). We also investigated the regional differences on the basis of T-score among the skeletal sites. Furthermore, the reliability of distal forearm DXA measurements was validated by assessing the statistical correlation (r) with volumetric BMD by computed tomography (CT).

RESULTS

Compared with the control group, the fracture group showed significantly lower BMD and T-scores and higher proportions of patients with a T-score of ≤-2.5 SD at the ultra-distal, mid-distal, and one-third distal forearm; however, the spine and hip measurements did not differ significantly between the 2 groups. With respect to regional differences, in the fracture group, T-scores were significantly lower and the proportions of patients with a T-score of ≤-2.5 SD were significantly higher for the 3 distal forearm sites compared with the spine and hip. DXA measurements at all 3 of the distal forearm regions exhibited high correlation with volumetric BMD by CT (r = 0.83 to 0.92).

CONCLUSIONS

Some postmenopausal women were found to exhibit bone loss preferentially at the distal part of the radius, which may render them vulnerable to fragility fractures. Forearm DXA for the assessment of local bone loss may demonstrate benefit in screening for those at risk for distal radial fractures and facilitate the early identification of patients who require intervention for osteoporosis.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Differences in Trabecular Plate and Rod Structure in Premenopausal Women Across the Weight Spectrum

CONTEXT

Premenopausal women with anorexia nervosa (AN) and obesity (OB) have elevated fracture risk. More plate-like and axially aligned trabecular bone, assessed by individual trabeculae segmentation (ITS), is associated with higher estimated bone strength. Trabecular plate and rod structure has not been reported across the weight spectrum.

OBJECTIVE

To investigate trabecular plate and rod structure in premenopausal women.

DESIGN

Cross-sectional study.

SETTING

Clinical research center.

PARTICIPANTS

A total of 105 women age 21 to 46 years: (i) women with AN (n = 46), (ii) eumenorrheic lean healthy controls (HCs) (n = 29), and (iii) eumenorrheic women with OB (n = 30).

MEASURES

Trabecular microarchitecture by ITS.

RESULTS

Mean age (±SD) was similar (28.9 ± 6.3 years) and body mass index differed (16.7 ± 1.8 vs 22.6 ± 1.4 vs 35.1 ± 3.3 kg/m2; P < 0.0001) across groups. Bone was less plate-like and axially aligned in AN (P ≤ 0.01) and did not differ between OB and HC. After controlling for weight, plate and axial bone volume fraction and plate number density were lower in OB vs HC; some were lower in OB than AN (P < 0.05). The relationship between weight and plate variables was quadratic (R = 0.39 to 0.70; P ≤ 0.0006) (i.e., positive associations were attenuated at high weight). Appendicular lean mass and IGF-1 levels were positively associated with plate variables (R = 0.27 to 0.67; P < 0.05). Amenorrhea was associated with lower radial plate variables than eumenorrhea in AN (P < 0.05).

CONCLUSIONS

In women with AN, trabecular bone is less plate-like. In women with OB, trabecular plates do not adapt to high weight. This is relevant because trabecular plates are associated with greater estimated bone strength. Higher muscle mass and IGF-1 levels may mitigate some of the adverse effects of low weight or excess adiposity on bone.

Bone Microarchitecture and Distal Radius Fracture Pattern Complexity

Distal radius fractures (DRFs) occur in various complexity patterns among patients differing in age, gender, and bone mineral density (BMD). Our aim was to investigate the association of patient characteristics, BMD, bone microarchitecture, and bone strength with the pattern complexity of DRFs. In this study, 251 patients aged 50-90 years with a radiologically confirmed DRF who attended the Fracture Liaison Service of VieCuri Medical Centre, the Netherlands, between November 2013 and June 2016 were included. In all patients fracture risk factors and underling metabolic disorders were evaluated and BMD measurement with vertebral fractures assessment by dual-energy X-ray absorptiometry was performed. Radiographs of all DRFs were reviewed by two independent investigators to assess fracture pattern complexity according to the AO/OTA classification in extra-articular (A), partially articular (B), and complete articular (C) fractures. For this study, patients with A and C fractures were compared. Seventy-one patients were additionally assessed by high-resolution peripheral quantitative computed tomography. Compared to group A, mean age, the proportion of males, and current smokers were higher in group C, but BMD and prevalent vertebral fractures were not different. In univariate analyses, age, male gender, trabecular area, volumetric BMD (vBMD), and stiffness were associated with type C fractures. In multivariate analyses, only male gender (odds ratio (OR) 8.48 95% confidence interval (CI) 1.75-41.18, p = 0.008]) and age (OR 1.11 [95% CI 1.03-1.19, p = 0.007]) were significantly associated with DRF pattern complexity. In conclusion, our data demonstrate that age and gender, but not body mass index, BMD, bone microarchitecture, or strength were associated with pattern complexity of DRFs.© 2019 The Authors. Journal of Orthopaedic Research® Published by Wiley Periodicals, Inc. J Orthop Res 37:1690-1697, 2019.

Effect of intracortical bone properties on the phase velocity and cut-off frequency of low-frequency guided wave modes (20-85 kHz)

The assessment of intracortical bone properties is of interest since early-stage osteoporosis is associated with resorption in the endosteal region. However, understanding the interaction between ultrasonic guided waves and the cortical bone structure remains challenging. The purpose of this work is to investigate the effect of intracortical bone properties on the ultrasonic response obtained at low-frequency (<100 kHz) using an axial transmission configuration. The semi-analytical finite element method was used to simulate the propagation of guided waves in a waveguide with realistic geometry and material properties. An array of 20 receivers was used to calculate the phase velocity and cut-off frequency of the excited modes using the two-dimensional Fourier transform. The results show that the position of the emitter around the circumference of the bone is an important parameter to control since it can lead to variations of up to 10 dB in the amplitude of the transmitted modes. The cut-off frequency of the high order modes was, however, only slightly affected by the circumferential position of the emitter, and was sensitive mainly to the axial shear modulus. The phase velocity and cut-off frequency in the 20-85 kHz range are promising parameters for the assessment of intracortical properties.

Long-Term and Recent Weight Change Are Associated With Reduced Peripheral Bone Density, Deficits in Bone Microarchitecture, and Decreased Bone Strength: The Framingham Osteoporosis Study

Weight loss in older adults is associated with increased bone loss and fracture. Little is known about the potential impact of weight loss on cortical and trabecular bone density, microarchitecture, and strength. In this study, participants were members of the Framingham Offspring Cohort (769 women, 595 men; mean age 70 ± 8 years), who underwent high-resolution peripheral quantitative computed tomography (HR-pQCT) scanning at the tibia and radius in 2012 to 2016. Weight measurements taken every 4 to 6 years were used to assess recent weight change over 6 years and long-term change over 40 years. General linear models, adjusting for age, sex, height, smoking, and diabetes, were used to evaluate the association between HR-pQCT indices and relative long-term and recent weight change. We found that long-term and recent weight loss were associated with lower cortical density and thickness, higher cortical porosity, and lower trabecular density and number. Associations were stronger for the tibia than radius. Failure load was lower in those individuals with long-term but not short-term weight loss. Deterioration in both cortical and trabecular indices, especially at the weight-bearing skeleton, characterizes bone fragility associated with long-term and recent weight loss in older adults. © 2018 American Society for Bone and Mineral Research.

Fixation Strength in Full and Limited Fixation of Osteoporotic Distal Radius Fractures

BACKGROUND

The purpose of this investigation is to determine whether osteoporotic intra-articular distal radius fractures surgically treated by filling all 7 distal screws of a volar plate will have a higher load to failure than those treated by filling only 4 distal screws.

METHODS

Ten matched pairs of fresh frozen cadaveric forearms were randomized within each pair to be treated by using either all 7 of the distal holes of a volar plate or only 4 distal screws. The distal radius fixation was performed with unicortical screws going to but not through the dorsal cortex, and the most distal screws were placed within 4 mm of the joint surface. An AO C2 type fracture was then created. All specimens were tested cyclically, with an axial load of 60 N, at 3 Hz for 1000 cycles to simulate early postoperative motion. All specimens were subsequently tested to mechanical failure.

RESULTS

There were no failures in either group during cyclic testing. There was no difference detected between groups for mean stiffness, yield load, peak load, or load to clinical failure. In both groups, the yield load, peak load, and load to clinical failure were higher than the 60- to 100-N forces encountered during postoperative rehabilitation.

CONCLUSIONS

There was no difference detected between osteoporotic intra-articular distal radius fractures treated by utilizing all 7 of the distal screws of a volar plate compared with those treated with only 4 distal screws.

Characterization of trabecular bone microstructure in premenopausal women with distal radius fractures

Individual trabecular segmentation was utilized to identify differences in trabecular bone structure in premenopausal women with wrist fractures and non-fracture controls. Fracture subjects had reduced trabecular plate volume, number, thickness, and connectivity. Identifying altered trabecular microarchitecture in young women offers opportunities for counseling and lifestyle modifications to reduce fracture risk.

INTRODUCTION

Premenopausal women with distal radius fractures (DRF) have worse trabecular bone microarchitecture than non-fracture controls (CONT), yet the characteristics of their trabecular bone structure are unknown.

METHODS

Premenopausal women with DRF (n = 40) and CONT (n = 80) were recruited. Primary outcome variables included trabecular structure at the distal radius and tibia, assessed by volumetric decomposition of individual trabecular plates and rods from high-resolution peripheral quantitative CT images. Trabecular morphology included plate and rod number, volume, thickness, and connectivity. Areal bone mineral density (aBMD) of the femoral neck (FN aBMD), and ultradistal radius (UDR aBMD) were measured by DXA.

RESULTS

Trabecular morphology differed between DRF and CONT at the radius and tibia (OR per SD decline 1.58-2.7). At the radius, associations remained significant when adjusting for age and FN aBMD (ORs = 1.76-3.26) and age and UDR aBMD (ORs = 1.72-3.97). Plate volume fraction, number and axially aligned trabeculae remained associated with DRF after adjustment for trabecular density (ORs = 2.55-2.85). Area under the curve (AUC) for discriminating DRF was 0.74 for the proportion of axially aligned trabeculae, compared with 0.60 for FN aBMD, 0.65 for UDR aBMD, and 0.69 for trabecular density. Plate number, plate-plate junction, and axial bone volume fraction remained associated with DRF at the tibia (ORs = 2.14-2.77) after adjusting for age, FN aBMD, or UDR aBMD. AUC_P.P.Junc.D was 0.72 versus 0.61 for FNaBMD, 0.66 for UDRaBMD, and 0.70 for trabecular density.

CONCLUSION

Premenopausal women with DRF have lower trabecular plate volume, number, thickness, and connectivity than CONT. Identification of young women with altered microarchitecture offers opportunities for lifestyle modifications to reduce fracture risk.

Diabetes and Deficits in Cortical Bone Density, Microarchitecture, and Bone Size: Framingham HR-pQCT Study

Older adults with type 2 diabetes (T2D) tend to have normal or greater areal bone mineral density (aBMD), as measured by DXA, than those who do not have diabetes (non-T2D). Yet risk of fracture is higher in T2D, including 40% to 50% increased hip fracture risk. We used HR-pQCT to investigate structural mechanisms underlying skeletal fragility in T2D. We compared cortical and trabecular bone microarchitecture, density, bone area, and strength in T2D and non-T2D. In secondary analyses we evaluated whether associations between T2D and bone measures differed according to prior fracture, sex, and obesity. Participants included 1069 members of the Framingham Study, who attended examinations in 2005 to 2008 and underwent HR-pQCT scanning in 2012 to 2015. Mean age was 64 ± 8 years (range, 40 to 87 years), and 12% (n = 129) had T2D. After adjustment for age, sex, weight, and height, T2D had lower cortical volumetric BMD (vBMD) (p < 0.01), higher cortical porosity (p = 0.02), and smaller cross-sectional area (p = 0.04) at the tibia, but not radius. Trabecular indices were similar or more favorable in T2D than non-T2D. Associations between T2D and bone measures did not differ according to sex or obesity status (all interaction p > 0.05); however, associations did differ in those with a prior fracture and those with no history of fracture. Specifically, cortical vBMD at the tibia and cortical thickness at the radius were lower in T2D than non-T2D, but only among those individuals with a prior fracture. Cortical porosity at the radius was higher in T2D than non-T2D, but only among those who did not have a prior fracture. Findings from this large, community-based study of older adults suggest that modest deterioration in cortical bone and reductions in bone area may characterize diabetic bone disease in older adults. Evaluation of these deficits as predictors of fracture in T2D is needed to develop prevention strategies in this rapidly increasing population of older adults. © 2017 American Society for Bone and Mineral Research.

Lower preoperative Hounsfield unit values are associated with intra-operative fractures in cementless bipolar hemiarthroplasty

The use of Hounsfield units (HU) from CT scanning to assess regional BMD has been described. Therefore, we evaluated whether HU could be used to identify osteoporosis of the proximal part of the femur. The results showed that HU assessment is associated with the presence of intra-operative fracture during arthroplasty.

INTRODUCTION

The aim with this study was to determine the association of preoperative Hounsfield unit (HU) in hip computed tomography (CT) with intra-operative osteoporotic fracture during cementless hemiarthroplasty.

METHODS

In this retrospective study, we reviewed all patients who underwent cementless bipolar hemiarthroplasty for femoral neck fractures between 2014 and 2016. Patients with intra-operative metaphyseal fractures (n = 25) during surgery were identified from a retrospectively collected patient database and matched with nonfracture controls (n = 75) on the basis of age and sex. The differences between patients with intra-operative fractures and without intra-operative fractures were compared regarding preoperative HU. Correlations of HU value of femur neck with BMD and T scores were determined.

RESULTS

Analysis of HU values at the fracture level showed a significantly lower value in the fracture group than in the controls (1186 vs 1340, p = 0.005). The correlation between HU and BMD of femur neck was significant (r ² = 0.347; p < 0.001). The correlation between HU of femur neck and BMD of spine was also significant (r ² = 0.133; p < 0.001).

CONCLUSIONS

HU assessment using preoperative CT scan is associated with the presence of intra-operative fracture during bipolar hemiarthroplasty. We believe that HU values of the proximal femur could be used to assess local bone quality.

Bone Strength Estimated by Micro-Finite Element Analysis (µFEA) Is Heritable and Shares Genetic Predisposition With Areal BMD: The Framingham Study

Genetic factors contribute to the risk of bone fractures, partly because of effects on bone strength. High-resolution peripheral quantitative computed tomography (HR-pQCT) estimates bone strength using micro-finite element analysis (µFEA). The goal of this study was to investigate if the bone failure load estimated by HR-pQCT-based µFEA is heritable and to what extent it shares genetic regulation with areal bone mineral density (aBMD). Bone microarchitecture was measured by HR-pQCT at the ultradistal tibia and ultradistal radius in adults from the Framingham Heart Study (n = 1087, mean age 72 years; 57% women). Radial and tibial failure load in compression were estimated by µFEA. Femoral neck (FN) and ultradistal forearm (UD) aBMD were measured by dual-energy X-ray absorptiometry (DXA). Heritability (h2 ) of failure load and aBMD and genetic correlations between them was estimated adjusting for covariates (age and sex). Failure load values at the non-weight-bearing ultradistal radius and at the weight-bearing ultradistal tibia were highly correlated (r = 0.906; p < 0.001). Estimates of h2 adjusted for covariates were 0.522 for the radius and 0.497 for the tibia. Additional adjustment for height did not impact on the h2 results, but adjustment for aBMD at the UD and FN somewhat decreased h2 point estimates: 0.222 and 0.380 for radius and tibia, respectively. In bivariate analysis, there was a high phenotypic and genetic correlation between covariate-adjusted failure load at the radius and UD aBMD (ρP  = 0.826, ρG  = 0.954, respectively), whereas environmental correlations were lower (ρE  = 0.696), all highly significant (p < 0.001). Similar correlations were observed between tibial failure load and femoral neck aBMD (ρP  = 0.577, ρG  = 0.703, both p < 0.001; ρE  = 0.432, p < 0.05). These data from adult members of families from a population-based cohort suggest that bone strength of distal extremities estimated by micro-finite element analysis is heritable and shares some genetic composition with areal BMD, regardless of the skeletal site. © 2017 American Society for Bone and Mineral Research.

Topographical Anatomy of the Distal Ulna Attachment of the Radioulnar Ligament

PURPOSE

The deep component of the distal radioulnar ligament provides translational stability and rotational guidance to the forearm. However, controversy exists regarding the importance of this structure as well as the nature of its attachment to the distal ulna. We aimed to evaluate the topographic anatomy of the distal ulna attachment of both the superficial and the deep components of the radioulnar ligament and to assess the relationship between its internal and its external morphometry.

METHODS

Thirteen human distal ulnae attached by ulnar part of the distal radioulnar ligament were scanned using micro-computed tomography and reconstructed in 3 dimensions. In addition, the distal radioulnar ligaments were examined under polarized light microscopy to determine the histological characteristics of collagen contained within the ligaments.

RESULTS

The deep limbs have broad marginal insertions at the fovea, whereas the superficial limbs have a circular and condensed insertion to the ulnar styloid. The center of the deep limb was separated from the base of the ulnar styloid by a mean of 2.0 ± 0.76 mm, and this distance was positively correlated with the width of the ulnar styloid. The mean distance between the center of the ulnar head and the center of the fovea was 2.4 ± 0.58 mm. The proportion of collagen type I was lower in the deep limb than in the superficial limb.

CONCLUSIONS

This new observation of the footprint of the radioulnar ligament in the distal ulna indicates that the deep limb may serve as an internal capsular ligament of the distal radioulnar joint, whereas the superficial limb as the external ligament.

CLINICAL RELEVANCE

Knowledge of the topographic anatomy of the radioulnar ligament's attachment to the distal ulna may provide a better understanding of distal radioulnar ligament-related pathologies.

Increased cortical porosity in women with hip fracture

BACKGROUND

Hip fractures cause increased mortality and disability and consume enormous healthcare resources. Only 46% of hip fracture patients have osteoporosis at the total hip according to dual-energy X-ray absorptiometry (DXA) measurement. Cortical porosity increases with ageing and is believed to be important for bone strength.

OBJECTIVE

To investigate whether older women with hip fracture have higher cortical porosity than controls, and if so whether this difference is independent of clinical risk factors and areal bone mineral density (aBMD).

METHODS

From an ongoing population-based study, we identified 46 women with a prevalent X-ray-verified hip fracture and 361 control subjects without any fractures. aBMD was measured with DXA. High-resolution peripheral quantitative computed tomography was used to measure bone microstructure at the standard (ultradistal) site and at 14% (distal) of the tibial length.

RESULTS

Women with a previous hip fracture had lower aBMD at the femoral neck (-11.8%) and total hip (-14.6%) as well as higher cortical porosity at the ultradistal (32.1%) and distal (29.3%) tibia compared with controls. In multivariable logistic regression analysis, with adjustment for covariates (age, height, weight, smoking, calcium intake, physical activity, walk time, oral glucocorticoids, parental hip fracture, rheumatoid arthritis, previous fall, current bisphosphonate treatment and femoral neck aBMD), cortical porosity at the ultradistal [odds ratio per standard deviation increase (95% confidence interval) 2.61 (1.77-3.85)] and distal [1.57 (1.12-2.20)] sites was associated with prevalent hip fracture.

CONCLUSION

Cortical porosity was associated with prevalent hip fracture in older women independently of femoral neck aBMD and clinical risk factors.

[Clinical results following conservative and surgical treatment of osteoporotic distal radius fractures in the elderly : Overview of best available evidence]

Fractures of the distal radius in elderly patients increasingly contribute to the workload in emergency departments worldwide. There is still no consensus about the best treatment option, e. g. closed reduction and cast stabilization, percutaneous pinning, external fixation or open reduction and internal fixation with volar locking plates (ORIF). In addition, the influence of pharmacological antiosteoporotic treatment (e. g. bisphosphonates) is unclear. In this overview five comparative studies were analyzed, which had been identified in a previous systematic review. The evaluation included 3 cohort studies and 2 randomized trials enrolling a total of 515 patients. A clinical or statistical advantage of ORIF over conservative treatment with respect to DASH scores 12 months after the index fracture event could not be demonstrated with a mean difference of 0.25 (95 % confidence interval CI -0.57-1.07). According to current best scientific evidence from preclinical and clinical investigations, antiosteoporotic medication does not have an unfavorable influence on fracture healing and should be continued due to its proven effectiveness in reducing subsequent osteoporotic fractures. Following distal radius fractures in elderly patients with clinical risk factors, an osteoporosis screening should be routine practice and a specific therapy should be initiated if the fracture risk is increased.

Measurement of Distal Ulnar Hounsfield Units Accurately Predicts Bone Mineral Density of the Forearm

BACKGROUND

Hounsfield unit (HU) measurement obtained from computed tomography (CT) scans of the wrist is a potential new screening method for low bone mineral density (BMD). We hypothesized that HU measurements of the ulnar head obtained from CT scans would correlate with BMD assessed with dual x-ray absorptiometry (DXA) scans of the forearm.

METHODS

Patients with both upper-extremity CT and DXA scans performed at a single institution were included in the study. Hounsfield units were manually measured in the distal part of the ulna by 1 author blinded to the DXA results. Average values were then compared with forearm BMD values as determined with a DXA scan.

RESULTS

Seventy-seven CT scans of 74 patients were included. Average HU values were significantly lower in the osteoporotic and osteopenic groups in comparison with the normal BMD group. The upper limit of the 95% confidence interval for osteopenic patients was 145.9 HU. The average forearm T-score for patients with an HU value at or below the cutoff of 146 was significantly lower than the average T-score for those with an HU value of >146 HU (p < 0.0001). Sensitivity and negative predictive value for low BMD using this cutoff value were calculated to be 91% and 89%, respectively.

CONCLUSIONS

Distal ulnar HU measurements accurately reflect the BMD of the forearm as diagnosed with a DXA scan. Our results suggest that distal ulnar HU measurements of ≤146 HU are strongly associated with low BMD and that values above this cutoff accurately rule out low forearm BMD with a high degree of sensitivity and negative predictive value. Utilizing this technique may improve the capture of at-risk patients and streamline the screening process for osteoporosis.

LEVEL OF EVIDENCE

Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Elevated Bone Turnover Markers Are Associated With Distal Radius Fractures in Premenopausal Women

PURPOSE

To examine whether premenopausal women with distal radius fractures (DRF) have lower levels of 25-hydroxyvitamin D (25[OH]D) and increased levels of serum bone turnover markers (BTM) compared with control subjects without fracture.

METHODS

Premenopausal women with DRF (n = 20) were prospectively enrolled and compared with age-matched individuals without a fracture (n = 20). Outcome measures included serum levels of 25(OH)D, parathyroid hormone (PTH), markers of bone formation (osteocalcin [OC], N-terminal extension propeptide of type I collagen [P1NP], and bone-specific alkaline phosphatase [BSAP]), and markers of bone resorption (C-terminal telopeptide of type I collagen [CTX]). We assessed associations between BTM and DRF with conditional logistic regression and the utility of markers for fracture prediction with a receiver operator characteristic analysis.

RESULTS

The fracture group and control group were comparable in terms of age at menarche and BMI. Patients who had fractures had significantly greater levels of OC and P1NP, and demonstrated a nonsignificant increase in CTX. Levels of 25(OH)D, PTH, and BSAP were similar between groups. Conditional logistic regression revealed independent associations between DRF and increased levels of OC and CTX. Levels of 25(OH)D and PTH were not associated with DRF. Receiver operator characteristic analyses demonstrated moderate performance for OC, P1NP, BSAP, and CTX in predicting DRF.

CONCLUSIONS

Levels of 25(OH)D were not associated with DRF in premenopausal women. However, patients with DRF had increased levels of BTM of formation and resorption. Bone turnover markers may be helpful in predicting future fragility fractures in premenopausal women.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic II.

Heritability and Genetic Correlations for Bone Microarchitecture: The Framingham Study Families

High-resolution peripheral quantitative computed tomography (HR-pQCT) measures bone microarchitecture and volumetric bone mineral density (vBMD), important risk factors for osteoporotic fractures. We estimated the heritability (h² ) of bone microstructure indices and vBMD, measured by HR-pQCT, and genetic correlations (ρ_G ) among them and between them and regional aBMD measured by dual-energy X-ray absorptiometry (DXA), in adult relatives from the Framingham Heart Study. Cortical (Ct) and trabecular (Tb) traits were measured at the distal radius and tibia in up to 1047 participants, and ultradistal radius (UD) aBMD was obtained by DXA. Heritability estimates, adjusted for age, sex, and estrogenic status (in women), ranged from 19.3% (trabecular number) to 82.8% (p < 0.01, Ct.vBMD) in the radius and from 51.9% (trabecular thickness) to 98.3% (cortical cross-sectional area fraction) in the tibia. Additional adjustments for height, weight, and radial aBMD had no major effect on h² estimates. In bivariate analyses, moderate to high genetic correlations were found between radial total vBMD and microarchitecture traits (ρ_G from 0.227 to 0.913), except for cortical porosity. At the tibia, a similar pattern of genetic correlations was observed (ρ_G from 0.274 to 0.948), except for cortical porosity. Environmental correlations between the microarchitecture traits were also substantial. There were high genetic correlations between UD aBMD and multivariable-adjusted total and trabecular vBMD at the radius (ρ_G  = 0.811 and 0.917, respectively). In summary, in related men and women from a population-based cohort, cortical and trabecular microarchitecture and vBMD at the radius and tibia were heritable and shared some h² with regional aBMD measured by DXA. These findings of high heritability of HR-pQCT traits, with a slight attenuation when adjusting for aBMD, supports further work to identify the specific variants underlying volumetric bone density and fine structure of long bones. Knowledge that some of these traits are genetically correlated can serve to reduce the number of traits for genetic association studies. © 2016 American Society for Bone and Mineral Research.

Evaluation of trabecular bone score in patients with a distal radius fracture

We compared bone mineral density (BMD) and trabecular bone score (TBS) in postmenopausal women with a distal radius fracture older than 50 years with controls. Total hip BMD was significantly different, but TBS was not different between two groups, suggesting TBS does not reflect microarchitectural changes of the distal radius.

INTRODUCTION

The purpose of this study was to determine whether trabecular bone score (TBS) has additive value for discriminating distal radius fracture (DRF) independent of BMD.

METHODS

We compared BMD and TBS in 258 postmenopausal women with a DRF older than 50 years of age with age- and body mass index (BMI)-matched controls who had no history of osteoporotic fracture. BMD was measured at the lumbar spine and hip using dual energy X-ray absorptiometry scans (GE Lunar Prodigy). TBS was calculated on the same spine image. A multivariate logistic regression analysis was used to analyze the odds ratio (OR) for the occurrence of DRF using age, BMI, lumbar spine BMD, total hip BMD, and TBS.

RESULTS

Patients with a DRF had significantly lower BMDs at hip (neck, trochanter and total) than those of controls: 0.752 ± 0.097, 0.622 ± 0.089, and 0.801 ± 0.099 in patients and 0.779 ± 0.092, 0.648 ± 0.089, 0.826 ± 0.101 in controls. However, lumbar spine BMD and TBS were not significantly different between the groups (p = 0.400 and 0.864, respectively). The multivariate analysis indicated that only total hip BMD was significantly associated with the occurrence of DRF (OR, 10.231; 95 % confidence interval, 1.724-60.702; p = 0.010).

CONCLUSIONS

TBS was not different between women with a DRF and those without a history of osteoporotic fracture, suggesting that TBS measured at the lumbar spine does not reflect early microarchitectural changes of the distal radius. Only total hip BMD is associated with the risk of DRF in Korean women.

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.

Recent Update in the Diagnosis and Treatment of Bone Frailty in Patients with a Distal Radius Fracture

Distal radius fracture (DRF) is the most common upper extremity fracture in the elderly. Patients with a DRF have a two to fourfold higher risk of a subsequent fracture than those with no history of fractures, and DRFs occur on average 15 years earlier than hip fractures. Therefore, patients with a DRF offer physicians an important opportunity to diagnose and treat osteoporosis to prevent a secondary fracture. In this review, we provide recent update in the diagnosis and treatment of bone frailty in patients with a DRF.

Using Hounsfield Units to Assess Osteoporotic Status on Wrist Computed Tomography Scans: Comparison With Dual Energy X-Ray Absorptiometry

PURPOSE

Rates of evaluation and treatment for osteoporosis following distal radius fragility fractures remain low. As a subset of patients with these fractures undergo diagnostic computed tomography (CT) scan of the wrist, utilizing bone mineral density (BMD) measurements available with this imaging can be used to detect osteopenia or osteoporosis. This information may consequently prompt intervention to prevent a subsequent fracture. The purpose of this study was to determine if Hounsfield unit (HU) measurements at the wrist correlate with BMD measurements of the hip, femoral neck, and lumbar spine and to assess the ability of these HU measurements to detect osteoporosis of the hip.

METHODS

Forty-five female patients with distal radius fractures who underwent CT scan and dual energy x-ray absorptiometry scan as part of the management of their wrist fracture were identified. Bone mineral density measurements were made using the regional cancellous bone HU value at the capitate and compared with values obtained by a dual energy x-ray absorptiometry scan.

RESULTS

Hounsfield unit values at the capitate were significantly correlated with BMD and t scores at the femoral neck, hip, and lumbar spine. An HU threshold of 307 in the capitate optimized sensitivity (86%) and specificity (94%) for detecting osteoporotic patients.

CONCLUSIONS

By demonstrating that capitate HU measurements from clinical CT scans are correlated with BMD and t scores at the hip, femoral neck, and lumbar spine, our data suggest that clinical CT scans should have a role in detecting osteopenia and osteoporosis.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic III.

Cissus quadrangularis prevented the ovariectomy induced oxidative stress in the femur of adult albino rats

The increasing evidence suggesting the role of free radicals in bone resorption and bone loss prompted us to explore whether the consumption of antioxidant rich medicinal plant C. quadrangularis modifies antioxidant status in ovariectomized rats.

METHODS

Twenty four female adult rats, 90days old showing regular estrous cycles were used for the present study. The animals were divided into two groups. The Group-1 rats (n=6) were sham operated and Group-II rats were bilaterally ovariectomized (n=18) and treated with C. quadrangularis for sixty days (100mg/kg body weight and 250mg/kg body weight). After sixty days, the rats were killed, femora were dissected out, minced and homogenized in Tris-HCl buffer (pH 7.4) and the supernatant was collected and used for biochemical assays.

RESULTS

Ovariectomy registered a decrease (p<0.05) in the activities of SOD, GPx, GST, ALP, collagen content and increased (p<0.05) the activities of TRAP and lipid peroxidation. Simultaneous administration of C. quadrangularis maintained the enzyme activities in ovariectomized rats.

CONCLUSION

C. quadrangularis, a natural herb may be used to treat the estrogen deficiency/menopause onset and ovariectomy induced oxidative stress.

Bone strength and muscle properties in postmenopausal women with and without a recent distal radius fracture

Distal radius (wrist) fracture (DRF) in women over age 50 years is an early sign of bone fragility. Women with a recent DRF compared to women without DRF demonstrated lower bone strength, muscle density, and strength, but no difference in dual-energy x-ray absorptiometry (DXA) measures, suggesting DXA alone may not be a sufficient predictor for DRF risk.

INTRODUCTION

The objective of this study was to investigate differences in bone and muscle properties between women with and without a recent DRF.

METHODS

One hundred sixty-six postmenopausal women (50-78 years) were recruited. Participants were excluded if they had taken bone-altering medications in the past 6 months or had medical conditions that severely affected daily living or the upper extremity. Seventy-seven age-matched women with a fracture in the past 6-24 months (Fx, n = 32) and without fracture (NFx, n = 45) were measured for bone and muscle properties using the nondominant (NFx) or non-fractured limb (Fx). Peripheral quantitative computed tomography (pQCT) was used to estimate bone strength in compression (BSIc) at the distal radius and tibia, bone strength in torsion (SSIp) at the shaft sites, muscle density, and area at the forearm and lower leg. Areal bone mineral density at the ultradistal forearm, spine, and femoral neck was measured by DXA. Grip strength and the 30-s chair stand test were used as estimates of upper and lower extremity muscle strength. Limb-specific between-group differences were compared using multivariate analysis of variance (MANOVA).

RESULTS

There was a significant group difference (p < 0.05) for the forearm and lower leg, with the Fx group demonstrating 16 and 19% lower BSIc, 3 and 6% lower muscle density, and 20 and 21% lower muscle strength at the upper and lower extremities, respectively. There were no differences between groups for DXA measures.

CONCLUSIONS

Women with recent DRF had lower pQCT-derived estimated bone strength at the distal radius and tibia and lower muscle density and strength at both extremities.

Increased Cortical Porosity in Older Men With Fracture

Cortical porosity increases with age and affects bone strength, but its association with fracture in older men is unknown. The aim of this study was to investigate whether cortical porosity is associated with prevalent fractures in older men. A subsample of 456 men aged 80.2 ± 3.5 (mean ± SD) years, with available high-resolution peripheral quantitative computed tomography measurements at the tibia from the 5-year follow-up exam, was drawn from the prospective MrOS Gothenburg study. Dual-energy X-ray absorptiometry was used to measure areal bone mineral density (aBMD). Data on physical activity, calcium intake, medications, diseases, and smoking were collected on questionnaires at the follow-up exam. Of 87 men (19.1%) with fracture at or after age 50 years (all fracture group), 52 (11.4%) had had a self-reported fracture before the baseline exam and 35 (7.7%) had had an X-ray-verified fracture between baseline and follow-up. Men in the all-fracture group and in the X-ray-verified group had 15.8% (13.2% ± 4.9% versus 11.4% ± 3.8%; p < 0.001) and 21.6% (14.1% ± 5.2% versus 11.6% ± 3.9%; p < 0.01) higher cortical porosity, respectively, than men in the nonfracture group. The independent associations between bone microstructure parameters and fracture were tested using multivariate logistic regression with age, height, weight, calcium intake, smoking, physical activity, medications, and diseases as covariates. Cortical porosity was independently associated with any fracture (reported or X-ray-verified; OR per SD increase 1.49; 95% confidence interval (CI), 1.17 to 1.90) and with any X-ray-verified fracture alone (OR 1.73; 95% CI, 1.23 to 2.42). Including aBMD (spine or hip, respectively) in the multivariate logistic regression above revealed that cortical porosity was associated with any fracture (OR 1.54; 95% CI, 1.17 to 2.01) and with X-ray-verified fracture alone (OR 1.49; 95% CI, 1.00 to 2.22). Cortical porosity was associated with prevalence of fracture even after adjustment for aBMD.

Opportunistic Osteoporosis Screening - Gleaning Additional Information from Diagnostic Wrist CT Scans

BACKGROUND

Although screening for and treating osteoporosis can prevent subsequent fractures, the rates of such interventions are low following a distal radial fracture. One potential method for identifying metabolic bone disease is via Hounsfield unit (HU) measurements from diagnostic computed tomography (CT) scans. We hypothesized that HU values of the distal aspect of the radius could be used to assess local bone quality and would be predictive of distal radial fracture risk, thereby allowing the identification of patients in need of further management.

METHODS

Measurements of bone mineral density (BMD) were made for 100 patients on the basis of HU values of cancellous portions of the distal aspect of the radius, the ulnar head, and the capitate. The HU values in twenty-five male and twenty-five female patients with an acute distal radial fracture documented on CT were compared with those of age and sex-matched control patients who had a CT scan obtained for other indications.

RESULTS

Among the control patients, HU values decreased as age increased. When assessed on the basis of sex, both male and female patients with a distal radial fracture had significantly lower regional BMD compared with nonfracture control patients. A distal radial HU value of 218 for females and 246 for males optimized sensitivity and specificity; values below this threshold were associated with an increased risk of distal radial fracture.

CONCLUSIONS

HU measurements can be obtained from any diagnostic CT scan using modern software programs and can be obtained by physicians in the office setting with minimal effort and at no additional cost or radiation exposure to the patient. Regardless of imaging indications, we suggest that patients with HU values below the identified thresholds be considered for further metabolic bone disease work-up, such as additional imaging, laboratory assessments, the initiation of osteoporosis treatment, or appropriate referral.

Age-related differences in volumetric bone mineral density, microarchitecture, and bone strength of distal radius and tibia in Chinese women: a high-resolution pQCT reference database study

In a cohort of 393 Chinese women, by using high-resolution peripheral quantitative computed tomography (HR-pQCT), we found that significant cortical bone loss occurred after midlife. Prominent increase in cortical porosity began at the fifth decade but reached a plateau before the sixth decade. Trabecular bone loss was already evident in young adulthood and continued throughout life.

INTRODUCTION

This study aimed to investigate age-related differences in volumetric bone mineral density (vBMD), microarchitecture, and estimated bone strength at peripheral skeleton in Chinese female population.

METHODS

In a cross-sectional cohort of 393 Chinese women aged 20-90 years, we obtained vBMD, microarchtecture, and micro-finite element-derived bone strength at distal radius and tibia using HR-pQCT.

RESULTS

The largest predictive age-related difference was found for cortical porosity (Ct.Po) which showed over four-fold and two-fold differences at distal radius and tibia, respectively, over the adulthood. At both sites, cortical bone area, vBMD, and thickness showed significant quadratic association with age with significant decrease beginning after midlife. Change of Ct.Po became more prominent between age of 50 and 57 (0.26 %/year at distal radius, 0.54 %/year at distal tibia, both p ≤ 0.001) but thereafter, reached a plateau (0.015 and 0.028 %/year, both p > 0.05). In contrast, trabecular vBMD and microarchitecture showed linear association with age with significant deterioration observed throughout adulthood. Estimated age of peak was around age of 20 for trabecular vBMD and microarchitecture and Ct.Po and age of 40 for cortical vBMD and microarchitecture. Estimated stiffness and failure load peaked at mid-30s at the distal radius and at age 20 at distal tibia.

CONCLUSIONS

Age-related differences in vBMD and microarchitecture in Chinese women differed by bone compartments. Significant cortical bone loss occurred after midlife. Prominent increase in Ct.Po began at the fifth decade but appeared to be arrested before the sixth decade. Loss of trabecular bone was already evident in young adulthood and continued throughout life.

Trabecular and cortical microstructure and fragility of the distal radius in women

Fragility fractures commonly involve metaphyses. The distal radius is assembled with a thin cortex formed by fusion (corticalization) of trabeculae arising from the periphery of the growth plate. Centrally positioned trabeculae reinforce the thin cortex and transfer loads from the joint to the proximal thicker cortical bone. We hypothesized that growth- and age-related deficits in trabecular bone disrupt this frugally assembled microarchitecture, producing bone fragility. The microarchitecture of the distal radius was measured using high-resolution peripheral quantitative computed tomography in 135 females with distal radial fractures, including 32 girls (aged 7 to 18 years), 35 premenopausal women (aged 18 to 44 years), and 68 postmenopausal women (aged 50 to 76 years). We also studied 240 fracture-free controls of comparable age and 47 healthy fracture-free premenopausal mother-daughter pairs (aged 30 to 55 and 7 to 20 years, respectively). In fracture-free girls and pre- and postmenopausal women, fewer or thinner trabeculae were associated with a smaller and more porous cortical area (r = 0.25 to 0.71 after age, height, and weight adjustment, all p < 0.05). Fewer and thinner trabeculae in daughters were associated with higher cortical porosity in their mothers (r = 0.30 to 0.47, all p < 0.05). Girls and premenopausal and postmenopausal women with forearm fractures had 0.3 to 0.7 standard deviations (SD) fewer or thinner trabeculae and higher cortical porosity than controls in one or more compartment; one SD trait difference conferred odds ratio (95% confidence interval) for fracture ranging from 1.56 (1.01-2.44) to 4.76 (2.86-7.69). Impaired trabecular corticalization during growth, and cortical and trabecular fragmentation during aging, may contribute to the fragility of the distal radius.

A cohort study of 4,190 patients treated with low-intensity pulsed ultrasound (LIPUS): findings in the elderly versus all patients

BACKGROUND

Patient age is one of many potential risk factors for fracture nonunion. Our hypothesis is that older patients (≥ 60) with fracture risk factors treated with low-intensity pulsed ultrasound (LIPUS) have similar heal rate (HR) to the population as a whole. We evaluate the impact of age in conjunction with other risk factors on HR in LIPUS-treated patients with fresh fracture (≤ 90 days old).

METHODS

The Exogen Bone Healing System is a LIPUS device approved in 1994 to accelerate healing of fresh fracture. After approval, the FDA required a Post-Market Registry to assess performance. Patient data collected from October 1994 until October 1998 were individually reviewed and validated by a registered nurse. Four distinct data elements were required to report a patient: date fracture occurred; date treatment began; date treatment ended; and a dichotomous outcome of healed v. failed, by clinical and radiological criteria. Data were used to calculate two derived variables; days to treatment (DTT) and days on treatment (DOT). Every validated fresh fracture patient with DTT, DOT, and outcome is reported.

RESULTS

The validated registry had 5,765 patients with fresh fracture; 73% (N = 4,190) are reported, while 13% of patients were lost to follow-up, 11% withdrew or were non-compliant, and 3% died or are missing outcome. Among treatment-compliant patients, HR was 96.2%. Logistic estimates of the odds ratio for healing are equivalent for patients age 30 to 79 years and all age cohorts had a HR > 94%. Open fracture, current smoking, diabetes, vascular insufficiency, osteoporosis, cancer, rheumatoid arthritis, and prescription NSAIDs all reduced HR, but older patients (≥ 60) had similar HRs to the population as a whole. DTT was significantly shorter for patients who healed (p < 0.0001).

CONCLUSIONS

Comorbid conditions in conjunction with aging can reduce fracture HR. Patients with fracture who used LIPUS had a 96% HR, whereas the expected HR averages 93%. Time to treatment was significantly shorter among patients who healed (p < 0.0001), suggesting that it is beneficial to begin LIPUS treatment early. Older patients (≥ 60) with fracture risk factors treated with LIPUS exhibit similar heal rates to the population as a whole.

Diminished bone strength is observed in adult women and men who sustained a mild trauma distal forearm fracture during childhood

Children and adolescents who sustain a distal forearm fracture (DFF) owing to mild, but not moderate, trauma have reduced bone strength and cortical thinning at the distal radius and tibia. Whether these skeletal deficits track into adulthood is unknown. Therefore, we studied 75 women and 75 men (age range, 20 to 40 years) with a childhood (age < 18 years) DFF and 150 sex-matched controls with no history of fracture using high-resolution peripheral quantitative computed tomography (HRpQCT) to examine bone strength (ie, failure load) by micro-finite element (µFE) analysis, as well as cortical and trabecular bone parameters at the distal radius and tibia. Level of trauma (mild versus moderate) was assigned using a validated classification scheme, blind to imaging results. When compared to sex-matched, nonfracture controls, women and men with a mild trauma childhood DFF (eg, fall from standing height) had significant reductions in failure load (p < 0.05) of the distal radius, whereas women and men with a moderate trauma childhood DFF (eg, fall while riding a bicycle) had values similar to controls. Consistent findings were observed at the distal tibia. Furthermore, women and men with a mild trauma childhood DFF had significant deficits in distal radius cortical area (p < 0.05), and significantly lower dual-energy X-ray absorptiometry (DXA)-derived bone density at the radius, hip, and total body regions compared to controls (all p < 0.05). By contrast, women and men with a moderate trauma childhood DFF had bone density, structure, and strength that did not differ significantly from controls. These findings in young adults are consistent with our observations in children/adolescents with DFF, and they suggest that a mild trauma childhood DFF may presage suboptimal peak bone density, structure, and strength in young adulthood. Children and adolescents who suffer mild trauma DFFs may need to be targeted for lifestyle interventions to help achieve improved skeletal health.

Relationship of bone mineral density of spine and femoral neck to distal radius fracture stability in patients over 65

PURPOSE

We hypothesized that an increasing degree of osteopenia in the femoral neck and lumbar spine would be associated with loss of reduction after closed manipulation and splinting of distal radius fractures in patients over 65 years of age.

METHODS

We performed a retrospective review, evaluating 78 patients with displaced distal radius fractures managed with closed reduction and splinting. T-scores from the lumbar spine and femoral neck were recorded from dual-energy x-ray absorptiometry scans performed either within 1 year before or after injury. Volar tilt, radial height, radial inclination, and ulnar variance were evaluated from the initial fracture, postreduction, and final follow-up radiographs. We calculated the percentage of reduction maintained regarding reduction variable. We correlated T-scores of the lumbar spine and femoral neck with the percentage of retained reduction.

RESULTS

We found no correlation between T-scores of the lumbar spine or femoral neck and the amount of reduction lost throughout the healing process of distal radius fractures with respect to volar tilt, radial height, radial inclination, or ulnar variance. Reduction was of no anatomical benefit in 53% to radial height, 44% to radial inclination, and 54% to ulnar variance.

CONCLUSIONS

There appears to be no relationship between bone mineral density, based on T-scores of the lumbar spine and femoral neck, and the ability to maintain reduction after closed manipulation and splinting of displaced distal radius fractures in patients over 65 years of age.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic III.

The clinical significance of wrist fracture in osteoporosis

Wrist fracture is the most common fragility fracture in perimenopausal and young postmenopausal women in USA and Northern Europe. Recent studies based on high-resolution imaging have shown microarchitectural deterioration of trabecular bone even in premenopausal women presenting with a wrist fracture. These fractures increase the risk of subsequent fractures, especially in the first 7 years. So, wrist fracture female patients must be appropriately screened and treated for osteoporosis in order to preserve bone quality and prevent future, more severe, fractures.

A micro-architectural evaluation of osteoporotic human femoral heads to guide implant placement in proximal femoral fractures

BACKGROUND AND PURPOSE

The micro-architecture of bone has been increasingly recognized as an important determinant of bone strength. Successful operative stabilization of fractures depends on bone strength. We evaluated the osseous micro-architecture and strength of the osteoporotic human femoral head.

MATERIAL AND METHODS

6 femoral heads, obtained during arthroplasty surgery for femoral neck fracture, underwent micro-computed tomography (microCT) scanning at 30 μm, and bone volume ratio (BV/TV), trabecular thickness, structural model index, connection density, and degree of anisotropy for volumes of interest throughout the head were derived. A further 15 femoral heads underwent mechanical testing of compressive failure stress of cubes of trabecular bone from different regions of the head.

RESULTS

The greatest density and trabecular thickness was found in the central core that extended from the medial calcar to the physeal scar. This region also correlated with the greatest degree of anisotropy and proportion of plate-like trabeculae. In the epiphyseal region, the trabeculae were organized radially from the physeal scar. The weakest area was found at the apex and peripheral areas of the head. The strongest region was at the center of the head.

INTERPRETATION

The center of the femoral head contained the strongest trabecular bone, with the thickest, most dense trabeculae. The apical region was weaker. From an anatomical and mechanical point of view, implants that achieve fixation in or below this central core may achieve the most stable fixation during fracture healing.