Advance in osteoporosis screening methods / 中华内分泌代谢杂志

Osteoporosis has become a common chronic disease which seriously endangers the health of the elderly. China is facing high incidence of osteoporosis along with " three low" rates of screening, diagnosis, and treatment, the crux of which lies in the lack of convenient and effective screening methods for osteoporosis. DXA, the gold standard for the diagnosis of osteoporosis, has many setbacks such as expensive, radiation, and low accessibility in community, etc. which limits its application in large scale screening. The community screening methods for osteoporosis recommended by national guidelines are IOF one-minute test, osteoporosis self-assessment tool for Asians(OSTA), fracture risk assessment tool(FRAX ?), and quantitative ultrasound(QUS). In recent years, digital X-ray radiogrammetry(DXR) and opportunistic quantitative computed tomography(QCT)have also shown great potential in osteoporosis screening. This article reviews the application and research progress of the above screening methods, with the aim of improving the screening rate and contributing to the tertiary prevention and control mechanism of " wide awareness, early diagnosis and early treatment" of osteoporosis.

Quantifying cortical bone in fragmentary archeological second metacarpals.

OBJECTIVES: Skeletal variation in cortical bone thickness is an indicator of bone quality and health in archeological populations. Second metacarpal radiogrammetry, which measures cortical thickness at the shaft midpoint, is traditionally used to evaluate bone loss in bioarcheological and some clinical contexts. However fragmentary elements are regularly omitted because the midpoint cannot be determined. This methodological limitation reduces sample sizes and biases them against individuals prone to fracture, such as older individuals with low bone mass. This study introduces a new technique for measuring cortical bone in second metacarpals, the "Region of Interest" (ROI) method, which quantifies bone in archeological remains with less-than-ideal preservation while accounting for cortical heterogeneity. MATERIALS AND METHODS: The ROI method was adapted from digital X-ray radiogrammetry (DXR), a clinical method used to estimate bone mineral density, and tested using second metacarpals from Middenbeemster, Netherlands, a 19th century known age and sex skeletal collection. The ROI method quantifies cortical bone area within a 1.9 cm-long, mid-diaphyseal region, standardized for body size differences using total area (CAIROI ). CAIROI values were compared to traditional radiogrammetric cortical indices (CI) to assess the method's ability to identify age-related bone loss. RESULTS: CAIROI values have high intra- and interobserver replicability and are strongly and significantly correlated with CI values for both males (r[n = 39] = 0.906, p = 0.000) and females (r[n = 58] = 0.925, p = 0.000). CONCLUSION: The ROI method complements traditional radiogrammetry analyses and provides a reliable way to quantify cortical bone in incomplete second metacarpals, thereby maximizing sample sizes, allowing patterns in bone acquisition and loss to be more comprehensively depicted in archeological assemblages.

Screening for women with increased risk of fragility fractures in a general female population using digital X-ray radiogrammetry (DXR).

OBJECTIVE: To evaluate the predictive ability of digital X-ray radiogrammetry (DXR) for fracture in women attending general mammography screening. STUDY DESIGN: In a nested case-control study, women aged between 40 and 75 years, who attended the regional mammography screening program, had their bone mass assessed with DXR and provided information regarding clinical risk factors for osteoporosis. Follow-up was done through cross-referencing with National Patient Registers. Associations between DXR, clinical risk factors and fracture risk were examined. Receiver operating characteristics curves for DXR T-score and different fracture types were plotted, and their respective AUC calculated. MAIN OUTCOME MEASURES: Fractures (hip, major osteoporotic and any clinical facture). Fracture diagnoses were retrieved from National Patient Registers. RESULTS: 14,841 women had their bone mass examined in conjunction with mammography. Of these women, 10,967 returned fully completed questionnaires regarding clinical risk factors. In total 605 fractures (including 355 major osteoporotic fractures and 18 hip fractures) occurred during the follow-up period (median follow-up time was 3.3 years). Women with fractures were older and had lower DXR T-score compared with those without. DXR T-score correlated with fracture risk. HR/SD T-score decrease was 2.15 (CI 1.55-3.00) for hip, 1.47 (CI 1.36-1.59) for major osteoporotic and 1.33 (CI 1.26-1.42) for any clinical fracture. The AUCs for the different fracture types were 0.79 (hip), 0.69 (major osteoporotic) and 0.65 (any clinical). CONCLUSIONS: DXR T-score is negatively correlated with risk of fracture in a general female population. This indicates a potential use of DXR in population-based screening for osteoporosis.

Can digital X-ray radiogrammetry be an alternative for dual-energy X-ray absorptiometry in the diagnosis of secondary low bone quality in children?

Bone quality in children is generally measured with dual-energy X-ray absorptiometry (DXA). Digital X-ray radiogrammetry (DXR) uses BoneXpert to measure cortical bone quality on hand radiographs. This prospective study compared DXR and DXA results in children with high probability of secondary low bone quality, defined as DXA of the lumbar spine (DXALS) Z-score ≤ - 2.0. One hundred one children underwent both DXA and DXR assessment. DXALSZ-scores were also adjusted for bone age. DXR Z-scores were compared with both DXALSZ-scores, using Pearson correlations, Bland-Altman analysis, and sensitivity-specificity analysis. Mean bone age, DXR, and both DXA Z-scores were significantly impaired. Pearson correlation coefficients were significant between DXR Z-scores and both DXALSZ-scores 0.507-0.564 (p < 0.001). Bland-Altman analysis showed a mean difference of 0.05-0.48 between DXR and both DXA Z-scores and showed more than 90% similarity for both DXALSZ-scores ≤ - 2.0. DXR had a sensitivity of 67-71% and specificity of 77-83% compared to both DXALSZ-scores.Conclusion: DXR correlates well with as well DXALS as bone age-adjusted DXALSZ-scores and shows good agreement with as well DXALS as bone age-adjusted DXALSZ-scores ≤ - 2.0. DXR shows best results when compared with DXALSZ-scores. What is Known: • Digital X-ray radiogrammetry (DXR) may correlate well with dual-energy X-ray absorptiometry (DXA) in pediatric, adolescent, and adult patients. • DXR is a feasible method for assessment of bone quality in children. What is New: • This is the first prospective study in children with suspected secondary low bone quality that illustrates correlation between DXR and bone age-adjusted DXA Z-scores and that shows good agreement between DXR and DXA as bone age-adjusted DXA Z-scores ≤ -2.0. • Our results suggest DXR to be a good alternative for DXA for determining low bone quality.

Inhibition of periarticular bone loss is associated with clinical remission and ACR70-Response in rheumatoid arthritis.

The aim of this study, based on a post hoc analysis of the data set used in the RAPID 1 trial, focuses on the associations between metacarpal bone mineral density, as estimated by digital X-ray radiogrammetry (DXR), and clinical remission as well as ACR70-Response in rheumatoid arthritis (RA) patients treated with certolizumab pegol (CZP). The trial evaluates a total of 345 RA patients treated with methotrexate versus CZP 200 mg versus CZP 400 mg. All patients underwent X-rays of the hand at baseline and week 52 as well as computerized calculations of bone mineral density (BMD) by DXR. Clinical remission was defined as DAS28 < 2.6. ACR70-Response was also evaluated. The radiological assessment of disease progression was estimated using the modified total Sharp Score. The mean difference for DAS28 was observed for patients treated with CZP 400 mg (median: - 3.53, minimum: - 6.77; maximum: + 0.48) and CZP 200 mg (median: - 3.13, minimum: - 6.37; maximum: - 0.52) compared to the methotrexate group (median - 2.41, minimum: - 4.76; maximum: + 0.31). The DXR-BMD showed a minor bone loss for the treatment groups undergoing therapy with CZP 200 mg (median: - 0.009 g/cm2, minimum: - 0.059 g/cm2; maximum: + 0.095 g/cm2) and CZP 400 mg (median: - 0.008 g/cm2, minimum: - 0.064 g/cm2; maximum: + 0.080 g/cm2). The methotrexate group presented an advanced periarticular metacarpal bone loss as measured by DXR-BMD (median: - 0.024 g/cm2, minimum: - 0.102 g/cm2; maximum: + 0.057 g/cm2). In the case of clinical remission and ACR70-Response, no significant change of the DXR-BMD was observed for both CZP groups. The study highlights that patients treated with CZP show a less accentuated periarticular bone loss as estimated by DXR in comparison to patients with methotrexate plus placebo. In addition, patients with clinical remission and ACR70-Response revealed no periarticular demineralisation.

Bone health of children with intestinal failure measured by dual energy X-ray absorptiometry and digital X-ray radiogrammetry.

BACKGROUND & AIMS: Children with intestinal failure (IF) receiving long-term parenteral nutrition (PN) are at risk of developing low bone mineral density (BMD). Next to the dual energy X-ray absorptiometry (DXA) method, digital X-ray radiogrammetry (DXR) using the BoneXpert software has become available to obtain the Bone Health Index (BHI) in hand radiographs. In this study we 1) evaluated the prevalence of low BMD in children with IF using DXA and DXR, 2) compared DXA and DXR results, and 3) aimed to identify factors associated with low BMD. METHODS: A retrospective study was performed including all children with IF between 2000 and 2015 who underwent a DXA measurement and/or a hand radiograph. Z-scores of BMD total body (BMD TB) and lumbar spine (BMD LS), bone mineral apparent density (BMAD) and bone health index (BHI) were collected. A low BMD and low BHI were defined as a Z-score ≤ -2. DXA and DXR results were compared for cases in which a DXA and hand radiograph were performed within a 6 months' interval. RESULTS: Forty-six children were included. Overall, 24.3% of the children had a low BMD at the first DXA at a median age of 6 years; correction for growth failure (n = 6) reduced this to 16.2%. Fifty percent had a low BHI at the first hand radiograph. Median DXA and BHI Z-scores were significantly lower than reference scores. Age, duration of PN and surgical IF were related to lower Z-scores at the first DXA. Paired DXA and DXR results (n = 18) were compared, resulting in a Cohen's kappa of 0.746 ('substantial') for BMD TB. Spearman's correlation coefficient for BHI and BMD TB Z-scores was 0.856 (p < 0.001). Hand radiography had a sensitivity of 90% and specificity of 86% (BMD TB). CONCLUSIONS: Up to 50% of the children had a low BMD. Children with IF have a significantly poorer bone health than the reference population, also after weaning off PN. Bone health assessment by DXA and DXR showed good agreement, especially for Z-scores ≤ -2. DXR assessment using BoneXpert software seems to be feasible for monitoring of bone health in children with IF.

Decrease in bone mineral density during three months after diagnosis of early rheumatoid arthritis measured by digital X-ray radiogrammetry predicts radiographic joint damage after one year.

BACKGROUND: Periarticular osteopenia is an early sign of incipient joint injury in rheumatoid arthritis (RA), but cannot be accurately quantified using conventional radiography. Digital X-ray radiogrammetry (DXR) is a computerized technique to estimate bone mineral density (BMD) from hand radiographs. The aim of this study was to evaluate whether decrease in BMD of the hands (BMD loss), as determined by DXR 3 months after diagnosis, predicts radiographic joint damage after 1 and 2 years in patients with early RA. METHODS: Patients (n = 176) with early RA (<12 months after onset of symptoms) from three different Swedish rheumatology centers were consecutively included in the study, and 167 of these patients were included in the analysis. Medication was given in accordance with Swedish guidelines, and the patients were followed for 2 years. Rheumatoid factor and antibodies to cyclic citrullinated peptides (anti-CCP) were measured at baseline, and 28-joint Disease Activity Score (DAS28) was assessed at each visit. Radiographs of the hands and feet were obtained at baseline, 3 months (hands only) and 1 and 2 years. Baseline and 1-year and 2-year radiographs were evaluated by the Larsen score. Radiographic progression was defined as a difference in Larsen score above the smallest detectable change. DXR-BMD was measured at baseline and after 3 months. BMD loss was defined as moderate when the decrease in BMD was between 0.25 and 2.5 mg/cm2/month and as severe when the decrease was greater than 2.5 mg/cm2/month. Multivariate regression was applied to test the association between DXR-BMD loss and radiographic damage, including adjustments for possible confounders. RESULTS: DXR-BMD loss during the initial 3 months occurred in 59% of the patients (44% moderate, 15% severe): 32 patients (19%) had radiographic progression at 1 year and 45 (35%) at 2 years. In multiple regression analyses, the magnitude of DXR-BMD loss was significantly associated with increase in Larsen score between baseline and 1 year (p = 0.033, adjusted R-squared = 0.069). CONCLUSION: DXR-BMD loss during the initial 3 months independently predicted radiographic joint damage at 1 year in patients with early RA. Thus, DXR-BMD may be a useful tool to detect ongoing joint damage and thereby to improve individualization of therapy in early RA.

Can secondary osteoporosis be identified when screening for osteoporosis with digital X-ray radiogrammetry? Initial results from the Stockholm Osteoporosis Project (STOP).

OBJECTIVES: To identify causes of low age-adjusted bone mass at digital X-ray radiogrammetry (DXR) in individuals attending an osteoporosis screening program. STUDY DESIGN: In a descriptive observational cohort study, women aged 40-75 years who attended a general mammography screening program had their bone mass investigated with DXR and answered a questionnaire regarding several clinical risk factors for osteoporosis. Each month the 2% with the lowest Z-scores were selected for further clinical examination with DXA of the hip and lumbar spine and pre-defined blood tests. MAIN OUTCOME MEASURE: Causes of secondary osteoporosis determined by clinical and laboratory evaluation. RESULTS: 14,783 women attended mammography screening and had their bone mass evaluated. In total, 327 women had a low DXR BMD and 281 accepted further DXA examination. Of these, 93 (33.1%) had osteoporosis. The diagnosis was new in 79 cases (84.9%) and in 32 (34.4%) a potential underlying cause was identified. Primary hyperparathyroidism was found in 8.6% and secondary hyperparathyroidism in 13.5%. Several self-reported risk factors for osteoporosis, including rheumatic disease, insulin-treated diabetes, cortisone treatment, smoking, reduced mobility, hyperparathyroidism, and malabsorption, were significantly more common among those selected for DXA referral than in the total cohort. For example, rheumatic disease and insulin-treated diabetes were reported 3.4 and 2.3 times as often, respectively. CONCLUSION: The prevailing potential cause of secondary osteoporosis according to DXR was primary and secondary hyperparathyroidism. Most of the women with these conditions were previously undiagnosed, indicating that further follow-up of patients with low age-adjusted DXR BMD is justified.

Fully Automated Deep Learning System for Bone Age Assessment.

Skeletal maturity progresses through discrete phases, a fact that is used routinely in pediatrics where bone age assessments (BAAs) are compared to chronological age in the evaluation of endocrine and metabolic disorders. While central to many disease evaluations, little has changed to improve the tedious process since its introduction in 1950. In this study, we propose a fully automated deep learning pipeline to segment a region of interest, standardize and preprocess input radiographs, and perform BAA. Our models use an ImageNet pretrained, fine-tuned convolutional neural network (CNN) to achieve 57.32 and 61.40% accuracies for the female and male cohorts on our held-out test images. Female test radiographs were assigned a BAA within 1 year 90.39% and within 2 years 98.11% of the time. Male test radiographs were assigned 94.18% within 1 year and 99.00% within 2 years. Using the input occlusion method, attention maps were created which reveal what features the trained model uses to perform BAA. These correspond to what human experts look at when manually performing BAA. Finally, the fully automated BAA system was deployed in the clinical environment as a decision supporting system for more accurate and efficient BAAs at much faster interpretation time (<2 s) than the conventional method.

Metacarpal bone loss in patients with rheumatoid arthritis estimated by a new Digital X-ray Radiogrammetry method - initial results.

BACKGROUND: The Digital X-ray Radiogrammetry (DXR) method measures the cortical bone thickness in the shafts of the metacarpals and has demonstrated its relevance in the assessment of hand bone loss caused by rheumatoid arthritis (RA). The aim of this study was to validate a novel approach of the DXR method in comparison with the original version considering patients with RA. METHOD: The study includes 49 patients with verified RA. The new version is an extension of the BoneXpert method commonly used in pediatrics which has these characteristics: (1) It introduces a new technique to analyze the images which automatically validates the results for most images, and (2) it defines the measurement region relative to the ends of the metacarpals. The BoneXpert method measures the Metacarpal Index (MCI) at the metacarpal bone (II to IV). Additionally, the MCI is quantified by the DXR X-posure System. RESULTS: The new version correctly analyzed all 49 images, and 45 were automatically validated. The standard deviation between the MCI results of the two versions was 2.9% of the mean MCI. The average Larsen score was 2.6 with a standard deviation of 1.3. The correlation of MCI to Larsen score was -0.81 in both versions, and there was no significant difference in their ability to detect erosions. CONCLUSION: The new DXR version (BoneXpert) validated 92% of the cases automatically, while the same good correlation to RA severity could be presented compared to the old version.

Hand bone loss in early rheumatoid arthritis during a methotrexate-based treat-to-target strategy with or without adalimumab-a substudy of the optimized treatment algorithm in early RA (OPERA) trial.

This study aims to investigate 1-year hand bone loss (HBL1-year) in early rheumatoid arthritis (RA) patients treated with a methotrexate (MTX) and intra-articular triamcinolone treat-to-target strategy +/- adalimumab and to determine if HBL6months is associated with radiographic progression after 2 years. In a clinical trial (OPERA) of 180 treatment-naive early RA patients, bone mineral density (BMD) was estimated from hand radiographs with digital X-ray radiogrammetry (DXR) at baseline, after 6 (n = 90) and 12 months (n = 70) of follow-up. Baseline and 2-year radiographs were scored according to the Sharp/van der Heijde method. Baseline characteristics and HBL6months (0-6 months changes in DXR-BMD) were investigated as predictors of structural damage by univariate linear (∆ total Sharp/van der Heijde score (TSS) as dependent variable) and logistic (+/-radiographic progression (∆TSS >0) as dependent variable) regression analyses. Variables with p < 0.10 were included in multivariable models. In 70 patients with available HBL1-year data, HBL1-year was median (interquartile range (IQR)) -1.9 (-3.3; -0.26 mg/cm2) in the MTX + placebo group and -1.8 (-3.6; 0.06) mg/cm2 in the MTX + adalimumab group, p = 0.98, Wilcoxon signed-rank. Increased HBL (compared to general population reference values) was found in 26/37 and 23/33 patients in the MTX + placebo and MTX + adalimumab groups, chi-squared = 0.99. In 90 patients with HBL6months data and 2-year radiographic data, HBL6months was independently associated with ∆TSS after 2 years (ß = -0.086 (95% confidence interval = -0.15; -0.025) TSS unit/mg/cm2 increase, p = 0.006) but not with presence of radiographic progression (∆TSS >0) (OR 0.96 (0.92-1.0), p = 0.10). In early RA patients treated with a methotrexate-based treat-to-target strategy, the majority of patients had increased HBL1-year, irrespective of adalimumab; HBL6months was independently associated with ∆TSS after 2 years.

Digital X-ray radiogrammetry and its sensitivity and specificity for the identification of rheumatoid arthritis-related cortical hand bone loss.

Digital X-ray radiogrammetry (DXR) is a computer-assisted diagnosis technique for quantifying cortical hand bone mineral density (BMD) as well as the metacarpal index (MCI) in the metacarpal bones from radiographs. The objective was to compare DXR-BMD and DXR-MCI between healthy individuals and patients with rheumatoid arthritis (RA) and verify the sensitivity and specificity of this technique for the identification of cortical hand bone loss as an additional diagnostic approach in RA. 618 patients were enrolled and divided into two groups: those with RA (n = 309) and a healthy control group (n = 309) as a reference database. DXR-BMD and the DXR-MCI were measured by DXR using hand radiographs. The severity of RA was evaluated by the modified Larsen score. Mean values for DXR-BMD and DXR-MCI in RA patients were significantly lower compared to healthy subjects (-20.7 and -21.1 %, respectively). Depending on the severity of RA-related joint damage, DXR-BMD revealed a significant reduction of -28.1 % and DXR-MCI -28.2 %, comparing score 1 and score 5 of the modified Larsen score. Both DXR-BMD and DXR-MCI had a high sensitivity (DXR-BMD 91 %, DXR-MCI 87 %) and a moderate specificity (DXR-BMD 47 %, DXR-MCI 49 %) to identify RA-related cortical hand bone loss. The DXR technique seems to be able to quantify RA-related periarticular bone loss as a characteristic feature in the course of RA. Consequently, periarticular osteoporosis seems to function as a reliable diagnostic approach comparable to erosions and joint space narrowing in the diagnosis of RA and as a surrogate marker for the progression of bone loss in RA.

Psoriatic arthritis is associated with bone loss of the metacarpals.

BACKGROUND: BoneXpert (BX) is a newly developed medical device based on digital X-ray radiogrammetry to measure human cortical bone thickness. The aim of this study was to quantify cortical bone loss of the metacarpals in patients with psoriatic arthritis (PsA) and compare these findings with other radiological scoring methods. METHODS: The study includes 104 patients with verified PsA. The BX method was used to measure the Metacarpal Index (MCI) at the metacarpal bones (II-IV). Additionally, the T-score of the MCI (T-scoreMCI) was calculated. Radiographic severity was determined by the Psoriatic Arthritis Ratingen Score (Proliferation Score and Destruction Score) as published by Wassenberg et al. and the Psoriatic Arthritis modified van der Heijde Sharp Score (Joint Space Narrowing Score and Erosion Score). RESULTS: For the total PsA study cohort, the T-scoreMCI was significantly reduced by -1.289 ± 1.313 SD. The MCI negatively correlated with the Proliferation Score (r = -0.732; p < 0.001) and the Destruction Score (r = -0.771; p < 0.001) of the Psoriatic Arthritis Ratingen Score. Lower coefficients of correlations were observed for the Psoriatic Arthritis modified van der Heijde Sharp Score. In this context, a severity-dependent and PsA-related periarticular demineralisation as measured by the MCI was quantified. The strongest reduction of -30.8 % (p < 0.01) was observed for the MCI in the Destruction Score. CONCLUSIONS: The BX MCI score showed periarticular demineralisation and severity-dependent bone loss in patients with PsA. The measurements of the BX technique were able to sensitively differentiate between the different stages of disease manifestation affecting bone integrity and thereby seem to achieve the potential to be a surrogate marker of radiographic progression in PsA.

A new implementation of digital X-ray radiogrammetry and reference curves of four indices of cortical bone for healthy European adults.

UNLABELLED: Digital X-ray radiogrammetry performs measurements on a hand radiograph in digital form. We present an improved implementation of the method and provide reference curves for four indices for the amount of bone. We collected 1662 hand radiographs of healthy subjects of age 9-100 years. PURPOSE: The digital X-ray radiogrammetry (DXR) method has been shown to be efficient for diagnosis of osteoporosis and for assessment of progression of rheumatoid arthritis. The aim of this work is to present a new DXR implementation and reference curves of four indices of cortical bone and to compare their relative SDs in healthy subjects at fixed age and gender. MATERIALS AND METHODS: A total of 1662 hand radiographs of healthy subjects of age 9-100 years were collected in Jena in 2001-2005. We also used a longitudinal study of 116 Danish children born in 1952 with on average 11 images taken over the age range 7 to 40 years. The new DXR method reconstructs the whole metacarpal contour so that the metacarpal lengths can be measured and used in two of the indices. The new DXR method automatically validates 97 % of the images and is implemented as a local server for PACS users. RESULTS: The Danish bone health index (BHI) data are consistent with the Jena data and also with the published BHI reference for healthy children. BHI is found to have smaller relative SD than the other three indices in the Jena cohort over the age range 20-80 years. CONCLUSION: The new DXR method is an extension of the existing BoneXpert method for children, which allows patients to be followed from childhood into adulthood with the same method. By making all four indices of cortical bone available within the same medical device, it becomes possible to decide which index has the best relation to fracture risk in future studies.

Digital X-ray radiogrammetry in the study of osteoporotic fractures: Comparison to dual energy X-ray absorptiometry and FRAX.

Osteoporosis is often underdiagnosed and undertreated. Screening of post-menopausal women for clinical risk factors and/or low bone mineral density (BMD) has been proposed to overcome this. Digital X-ray radiogrammetry (DXR) estimates hand BMD from standard hand X-ray images and have shown to predict fractures and osteoporosis. Recently, digital radiology and the internet have opened up the possibility of conducting automated opportunistic screening with DXR in post-fracture care or in combination with mammography. This study compared the performance of DXR with FRAX® and DXA in discriminating major osteoporotic fracture (MOF) (hip, clinical spine, forearm or shoulder), hip fracture and femoral neck osteoporosis. This prospective cohort study was conducted on 5278 women 65years and older in the Study of Osteoporotic Fractures (SOF) cohort. Baseline hand X-ray images were analyzed and fractures were ascertained during 10years of follow up. Age-adjusted area under receiver operating characteristic curve (AUC) for MOF and hip fracture and for femoral neck osteoporosis (DXA FN BMD T-score ≤-2.5) was used to compare the methods. Sensitivity to femoral neck osteoporosis at equal selection rates was tabulated for FRAX and DXR. DXR-BMD, FRAX (no BMD) and lumbar spine DXA BMD were all similar in fracture discriminative performance with an AUC around 0.65 for MOF and 0.70 for hip fractures for all three methods. As expected femoral neck DXA provided fracture discrimination superior both to other BMD measurements and to FRAX. AUC for selection of patients with femoral neck osteoporosis was higher with DXR-BMD, 0.76 (0.74-0.77), than with FRAX, 0.69 (0.67-0.71), (p<0.0001). In conclusion, DXR-BMD discriminates incident fractures to a similar degree as FRAX and predicts femoral neck osteoporosis to a larger degree than FRAX. DXR shows promise as a method to automatically flag individuals who might benefit from an osteoporosis assessment.

Striking difference of periarticular bone density change in early psoriatic arthritis and rheumatoid arthritis following anti-rheumatic treatment as measured by digital X-ray radiogrammetry.

OBJECTIVES: To examine changes in hand BMD as measured by digital X-ray radiogrammetry (DXR-BMD) in early PsA compared with RA patients prior to and 3 and 12 months after introducing an antirheumatic treatment. Further, to identify predictors for hand bone loss at the time of disease presentation. METHODS: Recent-onset, active, treatment-naïve patients were recruited. Clinical assessment, hand X-rays and DXR were obtained at 0, 3 and 12 months. Mean DXR-BMD for both hands and changes in DXR-BMD (mg/cm(2)/month) were compared between the two groups. We compared baseline disease characteristics of patients with normal hand DXR-BMD with those with bone loss. Logistic regression analyses were performed to identify predictors of hand BMD loss. RESULTS: A total of 64 patients were included. Hand DXR-BMD decreased in RA throughout the study (P = 0.043). Changes in periarticular bone density over 12 months differed between PsA and RA (P = 0.001). Hand bone loss at 3 months was associated with elevated BMI [odds ratio (OR) = 3.59, P = 0.041] and heavier alcohol intake (OR = 1.13, P = 0.035). Diagnosis of RA (OR = 57.48, P = 0.008), heavier alcohol intake (OR = 1.27, P = 0.012) and higher swollen joint count (SJC28) (OR = 1.5, P = 0.036) were independent predictors for hand bone loss in the first year. CONCLUSION: Following treatment, we found ongoing hand bone loss in RA and unchanged periarticular bone density in PsA, supporting the hypothesis that different pathomechanisms are involved in hand bone remodelling in PsA. Presence of RA, heavier alcohol intake and higher SJC were identified as independent predictors for hand bone loss over 1 year.

Reference values for digital X-ray radiogrammetry parameters in children and adolescents in comparison to estimates in patients with distal radius fractures.

The first objective of this study was to determine normative digital X-ray radiogrammetry (DXR) values, based on original digital images, in a pediatric population (aged 6-18 years). The second aim was to compare these reference data with patients suffering from distal radius fractures, whereas both cohorts originated from the same geographical region and were evaluated using the same technical parameters as well as inclusion and exclusion criteria. DXR-BMD and DXR-MCI of the metacarpal bones II-IV were assessed on standardized digital hand radiographs, without printing or scanning procedures. DXR parameters were estimated separately by gender and among six age groups; values in the fracture group were compared to age- and gender-matched normative data using Student's t tests and Z scores. In the reference cohort (150 boys, 138 girls), gender differences were found in bone mineral density (DXR-BMD), with higher values for girls from 11 to 14 years and for boys from 15 to 18 years (p < 0.05). Girls had higher normative metacarpal index (DXR-MCI) values than boys, with significant differences at 11-14 years (p < 0.05). In the case-control investigation, the fracture group (95 boys, 69 girls) presented lower DXR-BMD at 15-18 years in boys and 13-16 years in girls vs. the reference cohort (p < 0.05); DXR-MCI was lower at 11-18 years in boys and 11-16 years in girls (p < 0.05). Mean Z scores in the fracture group for DXR-BMD were -0.42 (boys) and -0.46 (girls), and for DXR-MCI were -0.51 (boys) and -0.53 (girls). These findings indicate that the fully digital DXR technique can be accurately applied in pediatric populations ≥ 6 years of age. The lower DXR-BMD and DXR-MCI values in the fracture group suggest promising early identification of individuals with increased fracture risk, without the need for additional radiation exposure, enabling the initiation of prevention strategies to possibly reduce the incidence of osteoporosis later in life.

Mammography and osteoporosis screening--clinical risk factors and their association with digital X-ray radiogrammetry bone mineral density.

The aim of this study was to study the association between digital X-ray radiogrammetry (DXR) T-score and clinical risk factors for osteoporosis. Women were recruited 2 d per wk at a single mammography screening center between year 2010 and 2012. Included women answered a questionnaire about risk factors for osteoporosis, and a radiograph of the nondominant hand was obtained for DXR analysis. Univariate associations between DXR T-score and risk factors were examined. A generalized linear regression model was fitted to independent variables with univariate associations at p<0.05. The multivariable model was reduced through manual backward elimination, with p>0.1 as the exclusion criterion. Seventy-six percent of the women chose to participate in the study (n=8810). The difference in number of daily mammograms performed on study vs nonstudy days was not significant. All univariate associations between DXR T-score and potential risk factors were highly significant. The multivariable model included height, weight, age, right-handedness, menopause before age 45, alcohol consumption, cortisone treatment, rheumatic disease, and age×smoking status. The coefficient of determination of the model was 0.37. The association between risk factors for osteoporosis and DXR T-score is similar to previously reported associations with dual-energy X-ray absorptiometry.

Potential sources of quantification error when retrospectively assessing metacarpal bone loss from historical radiographs by using digital X-ray radiogrammetry: an experimental study.

During the past 15 yr, digital X-ray radiogrammetry (DXR) has been used to measure metacarpal bone mineral density (BMD). BMD is often measured in existing cohorts where X-ray images were not acquired in accordance with the DXR imaging protocol (DIP). The purpose of the present study was to analyze how deviations from DIP in historical radiographs may affect the reproducibility of DXR-BMD measurements. Cadaver hand phantoms were used to conduct repeat measurements of deviations from DIP with respect to voltage, exposure, lateral displacement, supination, combination of lateral displacement and supination or rotation, extension of the wrist, and edge enhancement. Direct digital radiography (Aristos; Siemens Healthcare, Erlangen, Germany) was used for image acquisition and dxr-online (Sectra, Linköping, Sweden) for DXR-BMD measurements. The influence of the tested deviations from DIP ranged from 0 to 32.5 mg/cm(2) (0-6.8%). On repetition with the same specimen, none of the deviations resulted in a within-specimen reproducibility error greater than 2 mg/cm(2) (0.4%, equivalent to a T-score of 0.042). Among the tested deviations, all except tube voltage had a magnitude greater than the normal measurement noise for the technique and must therefore be considered when planning a study based on historical images.

Metacarpal Index Estimated by Digital X-ray Radiogrammetry as a Tool for Differentiating Rheumatoid Arthritis Related Periarticular Osteopenia.

UNLABELLED: To investigate Metacarpal Index (MCI) and Bone Mineral Density (BMD) estimated by Digital X-ray Radiogrammetry (DXR) with respect to its ability to quantify severity-dependent variations of bone mineralisation in patients with early rheumatoid arthritis compared to Dual Energy X-ray Absorptiometry (DXA), 122 patients underwent a prospective analysis of BMD and MCI by DXR, whereas both DXR-parameters were estimated from plain radiographs of the non-dominant hand. In comparison DXA measured BMD on total femur and lumbar spine (L2-L4). Additionally Steinbrocker Stage was assessed to differentiate the severity of rheumatoid arthritis (RA). Disease activity of RA was estimated by C-reactive Protein (CRP; in mg/l), Erythrocyte Sedimentation Rate (ESR in mm/1st hour) and by the disease activity score with 28-joint count (DAS 28). In consequence, The DXR-parameters, in particular DXR-MCI, revealed significant associations to age, Body Mass Index, CRP, DAS 28 and Steinbrocker graduation; no significant associations could be verified between DXA-parameters and all characteristics of disease activity and severity of RA. The highest correlation was found between DXR-MCI and DXR-BMD with R=0.89 (independent from severity of RA). In all patients DXR-MCI significantly decreased (-14.3%) from 0.42 ± 0.09 (stage 1) to 0.36 ± 0.07 (stage 2) dependent on severity of RA. The comparable relative reduction of DXR-BMD was -11.1%. The group of patients with minor disease activity (DAS 28>5.1) showed a significant flattened reduction (-11.4%) for DXR-MCI from 0.44 ± 0.08 (stage 1) to 0.39 ± 0.08 (stage 2). For accentuated disease activity (DAS 28>5.1) the DXR-MCI revealed a pronounced reduction (-23.1 %). No significant declines were observed for DXA-BMD of the lumbar spine and total femur in all patients as well as dependent on disease activity. CONCLUSION: DXR can exactly quantify cortical thinning of the metacarpal bones and can identify cortical demineralisation in patients suffering from early rheumatoid arthritis surpassing DXA-measurements at axial bone sites. In this context DXR-MCI seems to be the most sensitive parameter for differentiation of patients with minor or accentuated disease activity following severity-dependent cortical bone loss.