Digital X-ray Radiogrammetry Research Articles

Measuring metacarpal cortical bone by digital x-ray radiogrammetry: a step forward?

Changes in metacarpal cortical bone mineral density (BMD) using digital x-ray radiogrammetry were studied in patients with early rheumatoid arthritis. After 1, 2, and 5 years, large BMD losses were found: -1.7%, -2.8%, and -5.6%, respectively. Elevated erythrocyte sedimentation rate and anti-cyclic citrullinated peptide levels were independent predictors of bone loss, indicating that the largest amount of bone loss was found in patients with severe inflammation and high production of auto-antibodies, who are known to be at the highest risk of developing radiological bone damage. Studies are needed about the spatial and time relationship between erosions and juxta-articular and metacarpal bone loss.

Antibodies to cyclic citrullinated protein and erythrocyte sedimentation rate predict hand bone loss in patients with rheumatoid arthritis of short duration: a longitudinal study

IntroductionRadiographic progression in rheumatoid arthritis (RA) has in several studies been shown to be predicted by serological markers widely used in daily clinical practice. The objective of this longitudinal study was to examine if these serological markers also predict hand bone mineral density (BMD) loss in patients with RA of short disease duration.Methods163 patients with RA of short disease duration (2.4 years) were included and followed longitudinally. Antibodies to cyclic citrullinated protein (anti-CCP), rheumatoid factor (RF), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) were analysed from baseline blood-samples. Hand BMD was measured by digital X-ray radiogrammetry (DXR) based on hand and wrist radiographs obtained at baseline and 1, 2 and 5-year follow-up.ResultsDuring the study period, DXR-BMD decreased by median (inter quartile range) 1.7% (4.1 to 0.4), 2.8% (5.3 to 0.9) and 5.6% (11.7 to 2.3) after 1, 2 and 5 years, respectively. Elevated baseline anti-CCP, RF, ESR and CRP levels were in univariate linear regression analyses consistently associated with DXR-BMD change at all time-points. Anti-CCP and ESR were independently associated with hand DXR-BMD in multivariate linear regression analyses. Elevated anti-CCP levels were consistent and independent predictors of loss in cortical hand bone during the study period, with the odds ratios (95% confidence interval) 2.2 (1.0 to 4.5), 2.6 (1.1 to 6.2) and 4.9 (1.4 to 16.7) for the 1, 2, and 5-year follow-up periods, respectively.ConclusionsAnti-CCP and ESR were found to be independent predictors of early localised BMD loss. This finding adds to the understanding of anti-CCP and ESR as important predictors of bone involvement in RA.

Hand bone loss measured by digital X-ray radiogrammetry is a predictor of joint damage in early rheumatoid arthritis

Hand bone loss measured by digital X-ray radiogrammetry is a predictor of joint damage in early rheumatoid arthritis

106 Changes in Bone Mineral Density in Patients With Inflammatory Arthritis Using Digital X-Ray Radiogrammetry (DXR): Results from the Norfolk Arthritis Register (NOAR)

106 Changes in Bone Mineral Density in Patients With Inflammatory Arthritis Using Digital X-Ray Radiogrammetry (DXR): Results from the Norfolk Arthritis Register (NOAR)

Short-Time In Vitro and In Vivo Precision of Direct Digital X-ray Radiogrammetry

Digital X-ray radiogrammetry (DXR) calculates peripheral bone mineral density (BMD) from hand radiographs. The aim of this study was to examine in vitro and in vivo precision for the new direct digital version of DXR, a development of the conventional DXR. The in vitro precision for direct DXR was tested on 4 different X-ray equipments, based on 31 radiographs of the same phantom. The in vivo precision was based on duplicate hand radiographs from both hands in 39 individuals. For the 4 X-ray equipments, in vitro precision ranged from 0.14% to 0.30%, expressed as coefficient of variations (CV%) and from 0.0012 to 0.0028 g/cm 2, expressed as smallest detectable difference (SDD). The precision was correlated to the resolution of the radiographic equipment ( r = 0.95, p = 0.05). The corresponding values for the in vivo precision for mean values of both hands were: CV% = 0.46%; SDD = 0.0046 g/cm 2, and least significant change (LSC%) = 1.28%. The DXR-BMD for 1 of the X-ray equipments differed 1.1% from the overall mean. The precision for direct DXR was highly satisfactory both in vitro and in vivo. DXR-BMD values may differ between the radiographic equipments, and follow-up measurements should be performed with the same X-ray equipment.

Effects of leflunomide and methotrexate in rheumatoid arthritis detected by digital X-ray radiogrammetry and computer-aided joint space analysis

The aim of the present study was to evaluate the effect of long-term leflunomide and methotrexate (MTX) therapy during the course of rheumatoid arthritis (RA) estimated by digital X-ray radiogrammetry (DXR) and computer-aided joint space analysis (CAJSA) as diagnostic tools for the quantification of disease-related periarticular osteoporosis and joint space narrowing. Fourty matchable patients with verified RA were treated with leflunomide or MTX during an observation period of 2.5 years. All patients underwent complete computerized calculations of bone mineral density (BMD) and metacarpal index (MCI) by DXR as well as semi-automated measurements of joint space widths (JSW) at the metacarpophalangeal articulations (MCP, thumb to small finger) and proximal interphalangeal joints (PIP, index finger to small finger) using digitized hand radiographs. DXR-BMD revealed an increase of 0.4% (leflunomide-group) versus a reduction of -9.1% (MTX-group). Regarding DXR-MCI, a reduction of -1.1% (leflunomide-group) and -5.3% (MTX-group) was observed. The CAJSA parameters showed a decline of -2.7% (JSW-MCP) versus -2.1% (JSW-PIP) in patients treated with leflunomide. An accentuated joint space narrowing was revealed (JSW-MCP: -5.7%; JSW-PIP: -6.2%) in the MTX group. Digital X-ray radiogrammetry and CAJSA could discriminate the influence of different therapeutic regimes on periarticular osteoporosis and joint space narrowing showing a less accentuated radiographic progression in patients treated with leflunomide.

Efficacy Of GH-Treatment On BMD Changes In Children With GH-Deficiency, Followed Four Years By Digital X-Ray Radiogrammetry Vgrowth

Toll-like receptors (TLRs) are positioned at the interface between innate and adaptive immunity. Unlike others, those such as TLR9, that recognize nucleic acids, are confined to the endosomal compartment and are scarce on the cell surface. Here, we present evidence for TLR9 expression on the plasma membrane of B cells. In contrast to endosomal TLR9, cell surface TLR9 does not bind CpG-B oligodeoxynucleotides. After B cell-receptor (BCR) stimulation, TLR9 was translocated into lipid rafts with the BCR, suggesting that it could serve as a co-receptor for BCR. Nevertheless, stimulation of B cells with anti-TLR9 antibodies did not modify the BCR-induced responses despite up-regulation of tyrosine phosphorylation of proteins. However, CpG-B activation of B cells, acting synergistically with BCR signals, was inhibited by anti-TLR9 stimulation. Induction of CD25 expression and proliferation of B cells were thus down-regulated by the engagement of cell surface TLR9. Overall, our results indicate that TLR9 expressed on the plasma membrane of B cells might be a negative regulator of endosomal TLR9, and could provide a novel control by which activation of autoreactive B cells is restrained.

Changes in hand and generalised bone mineral density in patients with recent-onset rheumatoid arthritis

Objectives:To evaluate changes in bone mineral density (BMD) in the hands, hip and spine after 1 and 2 years of follow-up, in relation to antirheumatic and antiresorptive therapies and disease...

Cortical hand bone loss after 1 year in early rheumatoid arthritis predicts radiographic hand joint damage at 5-year and 10-year follow-up

Objective:To examine 1-year hand bone loss in early rheumatoid arthritis (RA) as a predictor of radiographic damage at 5-year and 10-year follow-upMethods:A total of 136 patients with RA (disease duration...

Effects of long-term immobilisation on cortical bone mass after traumatic amputation of the phalanges estimated by digital X-ray radiogrammetry

Osteopenia of the cortical and trabecular bone partition is a common finding after immobilisation. Digital X-ray radiogrammetry (DXR) seems to quantify cortical demineralisation caused by circular saw amputation already few days after accident. The study analyses the extent of demineralisation caused by immobilisation in patients with digital amputation after a circular saw injury, and elucidates the period of time which discloses a significant deprivation of bone mineral density estimated at the metacarpalia II-IV using DXR. Twenty-eight patients with digital amputations underwent measurements of bone mineral density, cortical thickness, bone width and metacarpal index using DXR-technology in a follow-up up to 902 days. The data showed a significant decline of bone mineral density (-10.47%), the metacarpal index (-4.38%), the bone width (-12.06%) and the cortical thickness (-7.04%) after trauma-related amputation. The cortical demineralisation of the metacarpals could already be revealed in two patients after the second day, according to the amputation of phalanges (-3.65%). The inhibition of the periosteal bone formation detected by DXR-technique seems to be a specific finding caused by amputation, which thus differs from normal age-related (i.e., endosteal) bone loss and from demineralisation following acute immobilisation (i.e., trabecular osteopenia).

Diagnosis of periarticular osteoporosis in rheumatoid arthritis using digital X-ray radiogrammetry

Osteoporosis can manifest in two ways in rheumatoid arthritis: generalized bone loss, which may result from immobility, the inflammatory process per se and/or treatments such as steroids; and periarticular demineralization, which is probably due to local release of inflammatory agents. Digital X-ray radiogrammetry (DXR) is an effective and sensitive modality for monitoring periarticular osteoporosis, which is among the earliest features of rheumatoid arthritis, preceding bone erosions. DXR is a promising technique, which can provide quantitative data that allow early diagnosis. During the course of rheumatoid arthritis it can be deployed in combination with established X-ray scoring methods to inform decisions regarding the optimal therapy to prevent joint destruction.

Digital X-ray radiogrammetry can provide outcome measures throughout the course of RA

Digital X-ray radiogrammetry can provide outcome measures throughout the course of RA

Low bone mineral density is associated with reduced hip joint space width in women

Since estrogen receptors (ER-alpha/ER-beta) were identified in human chondrocytes, animal and experimental studies have demonstrated the importance of continued estrogen production for the integrity of articular cartilage. However, human epidemiological support of the hypothesis has been inconclusive. The present cross-sectional study investigated the relationship between reduced bone mineral density (BMD), as a surrogate parameter of endogenous estrogen status assessed by digital x-ray radiogrammetry, and reduced minimum hip joint space width (JSW). Standardized hand radiographs of the Copenhagen Osteoarthritis Study cohort of 3,913 adults (1,470 male/2,443 female) with a mean age of 60 years (range, 18-92) were analyzed using X-Posure digital software, version 2.0 (Sectra-Pronosco). The system is operator independent. From 1,200 individual measurements per radiograph, mean BMD was calculated. Minimum hip JSW was assessed on standardized pelvic radiographs. Digital x-ray radiogrammetry BMD decreased in both men and women after the age of 45 years, progressively more so in women. Although minimum hip JSW in men remained relatively unaltered throughout life, a marked decline in female minimum hip JSW after age 45 years was observed. We found moderate but highly significant relationships between reduced BMD and reduced hip JSW in women (P < 0.0001), adjusted for age and dysplastic joint incongruity. We believe that the present study supports the hypothetical relationship between reduced estrogen levels and hip JSW reduction in women.

Assessment of the Osteoporotic Spine and Implications for Treatment

This section describes the various imaging modalities that exist today for evaluating bone density and thereby diagnosing osteopenia or osteoporosis. Osteoporosis is the most common metabolic abnormality of the bone, and fragility fractures due to osteoporosis have a tremendous impact in our aging society. Dual-energy X-ray absorptiometry scans, digital X-ray radiogrammetry, quantitative computed tomography, quantitative ultrasound, and magnetic resonance imaging are discussed in some detail. While the evaluation of bone density is important in any surgical treatment of the spine that involves decompression (which may remove some stabilizing tissues, imparting a greater load on remaining bony elements) or instrumentation (that depend on implant-bone fixation), the biggest clinical impact these imaging modalities have is in the diagnosis and subsequent management of osteoporotic vertebral compression fractures, which is the most common fracture of fragility that affects the elderly population.

Effect of combined agent of alendronate and alfacalcidol on bone mineral density followed by digital X-ray radiogrammetry (DXR-BMD)

Effect of combined agent of alendronate and alfacalcidol on bone mineral density followed by digital X-ray radiogrammetry (DXR-BMD)

Hand bone loss as an outcome measure in established rheumatoid arthritis: 2-year observational study comparing cortical and total bone loss

The aim of this 2-year longitudinal observational study was to explore hand bone loss as a disease outcome measure in established rheumatoid arthritis (RA).A cohort of 215 patients with RA (170 women and 45 men, aged 20–70 years) were recruited from the Oslo RA registry and studied for changes in hand bone mass during a 2-year follow-up. Digital X-ray radiogrammetry (DXR) was used to measure cortical hand bone mineral density (BMD) and metacarpal cortical index, whereas dual-energy X-ray absorptiometry (DXA) was used to assess whole hand BMD, which measures total cortical and trabecular bone. DXA-BMD total hip and spine and informative data for disease and therapy were also collected.Hand bone loss could be revealed over a 2-year follow-up measured by DXR-BMD (-0.90%, P < 0.01), but not by DXA-BMD (0.00%, P = 0.87). DXA-BMD hand bone loss was only observed in patients with disease duration ≤3 years and not in patients with longer disease duration (-0.96% versus 0.24%, P < 0.01), whereas loss of DXR-BMD was independent of disease duration. Disease activity (measured by the disease activity score including 28 joints) independently predicted loss of DXR-BMD but not changes in the DXA-BMD hand in the multivariate analysis. The change in DXR metacarpal cortical index was highly correlated to DXR-BMD (r = 0.94, P < 0.001).These data suggest that DXR-BMD may be a more appropriate technique to identify RA-related bone involvement in hands compared with DXA-BMD measurement, but further studies are needed to explore this hypothesis.

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

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 &gt; 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 &gt; 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. Keywords: digital X–ray radiogrammetry; dual energy X-ray absorptiometry; metacarpal index; bone mineral density; rheumatoid arthritis; steinbrocker stage

Digital X-ray radiogrammetry better identifies osteoarthritis patients with a low bone mineral density than quantitative ultrasound

This study assessed the ability of quantitative ultrasound (QUS) and digital X-ray radiogrammetry (DXR) to identify osteopenia and osteoporosis in patients with knee osteoarthritis (OA). One hundred and sixty-one patients with painful knee OA (81 men, 80 women; age 62.6+/-9.2 years, range 40-82 years) were included in this cross-sectional study and underwent dual-energy X-ray absorptiometry (DXA) of both hips and the lumbar spine, QUS of the phalanges and calcanei of both hands and heels, and DXR using radiographs of both hands. Unpaired t-test, Mann-Whitney U test, ROC analysis and Spearman's rank correlation were used for comparisons and correlation of methods. Using DXA as the reference standard, we defined a low bone mineral density (BMD) as a T-score < or =-1.0 at the lumbar spine or proximal femur. In contrast to phalangeal or calcaneal QUS, DXR was able to discriminate patients with a low BMD at the lumbar spine (p<0.0001) or hips (p<0.0001). ROC analysis showed that DXR had an acceptable predictive power in identifying OA patients a low hip BMD (sensitivity 70%, specificity 71%). Therefore, DXR used as a screening tool could help in identifying patients with knee OA for DXA.

Normative Data for Digital X-Ray Radiogrammetry From a Female and Male German Cohort

This study presents German reference data for digital X-ray radiogrammetry (DXR) differentiated by males as well as females, and quantifies for gender-specific and age-related differences including all DXR parameters. This study also documents the effects of different X-ray settings (e.g., radiographs of the wrist or the hand) on DXR measurements. There were 2085 patients who were prospectively enrolled (954 females and 1131 males) from a data pool of 11,915 patients with radiographs of the nondominant hand or wrist. All patients underwent measurements of bone mineral density (BMD), cortical thickness, bone width, and the metacarpal index (MCI) using DXR technology. These data showed a continuous age-related increase of the DXR parameters to the point of peak bone mass, then a continuous decline beyond the peak bone mass with accentuated age-related cortical bone loss in women. Peak bone mass is reached at approximately 30-34 yr for women and 45-49 yr for men. In addition, men had a significantly higher DXR BMD (mean: +12.8%) compared with woman in all age groups. Regarding the impact of various X-ray settings (e.g., X-ray(wrist) vs. X-ray(hand)), no significant difference was observed between both groups, men as well as women. The development of digital imaging technology has enabled more precise measurements of several radio-geometric features. The present study estimated normative reference values for DXR in German Caucasian women and men. Based on this reference data, a valid and reliable quantification of disease-related demineralization based on measurements of DXR BMD and MCI is now available for the Caucasian ethnic group.

Digital X-Ray Radiogrammetry Identifies Women at Risk of Osteoporotic Fracture: Results from a Prospective Study

Using digital X-ray radiogrammetry (DXR) on hand radiographs from a large population-based study, 1,370 postmenopausal women were evaluated in a prospective fashion; fracture occurrence was compared with DXR measurements of historic radiographs. Further, the aim of the study was to evaluate factors affecting DXR bone mineral density (BMD) in this cohort. The study is based on data from a subgroup of women participating in the third Copenhagen City Heart Study and additional data from a questionnaire obtained in 1999. The mean follow-up time was 6.1 years. During the observation period, 245 women suffered a fracture. Odds ratios (ORs) per 1 standard deviation decline in DXR-BMD were statistically significant for fracture in the groups of wrist fractures, proximal humerus fractures, vertebral fractures, and other fractures as well as in the total fracture group. In the hip fracture group, the P value almost reached significance (0.052). The highest ORs (2.4) were found in the group with proximal humerus fractures and in the vertebral fracture group (2.0). In the wrist fracture and hip fracture groups, ORs were 1.7 and 1.4, respectively. The group with other fractures had an OR of 1.7, and the OR in the entire fracture group was 1.6. Age, fracture, and smoking were negatively correlated with DXR-BMD, whereas BMI, age at menopause, hormone replacement therapy, and physical fitness and muscle strength were positively correlated with DXR-BMD. In conclusion, BMD estimated by DXR of the metacarpals predicts later osteoporotic fracture and seems to provide meaningful information on bone mass in epidemiological studies, where DXA measurements are not available.