Normative data for digital X-ray radiogrammetry from a female and male German cohort

The relationship between structural analysis of the hand and clinical characteristics in psoriatic arthritis

Up to now, there is only limited information available on a possible relationship between clinical characteristics and the mineralization of metacarpal bones and finger joint space distance (JSD) in patients with psoriatic arthritis (PsA). Computerized digital imaging techniques like digital X-ray radiogrammetry (DXR) and computer-aided joint space analysis (CAJSA) have significantly improved the structural analysis of hand radiographs and facilitate the recognition of radiographic damage. The objective of this study was to evaluate clinical features which potentially influence periarticular mineralization of the metacarpal bones and finger JSD in PsA-patients. 201 patients with PsA underwent computerized measurements of the metacarpal bone mineral density (BMD) with DXR and JSD of all finger joints by CAJSA. DXR-BMD and JSD were compared with clinical features such as age and sex, disease duration, C-reactive protein (CRP) as well as treatment with prednisone and disease-modifying antirheumatic drugs (DMARDs). A longer disease duration and an elevated CRP value were associated with a significant reduction of DXR-BMD, whereas JSD-parameters were not affected by both parameters. DXR-BMD was significantly reduced in the prednisone group (-0.0383 g/cm²), but prednisone showed no impact on finger JSD. Patients under the treatment with bDMARDs presented significant lower DXR-BMD (-0.380 g/cm²), JSD_MCP (-0.0179 cm), and JSD_PIP (-0.0121 cm) values. Metacarpal BMD was influenced by inflammatory activity, prednisone use, and DMARDs. In contrast, finger JSD showed only a change compared to baseline therapy. Therefore, metacarpal BMD as well as finger JSD represent radiographic destruction under different aspects.

Growth and puberty in children with juvenile idiopathic arthritis

Juvenile Idiopathic Arthritis is one of the most prevalent chronic diseases in children, with an annual incidence of 2-20 cases per 100,000 and a prevalence of 16-150 per 100,000. It is associated with several complications that can cause short-term or long-term disability and reduce the quality of life. Among these, growth and pubertal disorders play an important role. Chronic inflammatory conditions are often associated with growth failure ranging from slight decrease in height velocity to severe forms of short stature. The prevalence of short stature in JIA varies from 10.4% in children with polyarticular disease to 41% of patients with the systemic form, while oligoarthritis is mostly associated with localized excessive bone growth of the affected limb, leading to limb dissymmetry. The pathogenesis of growth disorders is multifactorial and includes the role of chronic inflammation, long-term use of corticosteroids, undernutrition, altered body composition, delay of pubertal onset or slow pubertal progression. These factors can exert a systemic effect on the GH/IGF-1 axis and on the GnRH-gonadotropin-gonadic axis, or a local influence on the growth plate homeostasis and function. Although new therapeutic options are available to control inflammation, there are still 10-20% of patients with severe forms of the disease who show continuous growth impairment, ending in a short final stature. Moreover, delayed puberty is associated with a reduction in the peak bone mass with the possibility of concomitant or future bone fragility. Monitoring of puberty and bone health is essential for a complete health assessment of adolescents with JIA. In these patients, an assessment of the pubertal stage every 6 months from the age of 9 years is recommended. Also, linear growth should be always evaluated considering the patient's bone age. The impact of rhGH therapy in children with JIA is still unclear, but it has been shown that if rhGH is added at high dose in a low-inflammatory condition, post steroids and on biologic therapy, it is able to favor a prepubertal growth acceleration, comparable with the catch-up growth response in GH-deficient patients. Here we provide a comprehensive review of the pathogenesis of puberty and growth disorders in children with JIA, which can help the pediatrician to properly and timely assess the presence of growth and pubertal disorders in JIA patients.

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.

Protecting Bone Health in Pediatric Rheumatic Diseases: Pharmacological Considerations

Bone health in children with rheumatic conditions may be compromised due to several factors related to the inflammatory disease state, delayed puberty, altered life style, including decreased physical activities, sun avoidance, suboptimal calcium and vitamin D intake, and medical treatments, mainly glucocorticoids and possibly some disease-modifying anti-rheumatic drugs. Low bone density or even fragility fractures could be asymptomatic; therefore, children with diseases of high inflammatory load, such as systemic onset juvenile idiopathic arthritis, juvenile dermatomyositis, systemic lupus erythematosus, and those requiring chronic glucocorticoids may benefit from routine screening of bone health. Most commonly used assessment tools are laboratory testing including serum 25-OH-vitamin D measurement and bone mineral density measurement by a variety of methods, dual-energy X-ray absorptiometry as the most widely used. Early disease control, use of steroid-sparing medications such as disease-modifying anti-rheumatic drugs and biologics, supplemental vitamin D and calcium, and promotion of weight-bearing physical activities can help optimize bone health. Additional treatment options for osteoporosis such as bisphosphonates are still controversial in children with chronic rheumatic diseases, especially those with decreased bone density without fragility fractures. This article reviews common risk factors leading to compromised bone health in children with chronic rheumatic diseases and discusses the general approach to prevention and treatment of bone fragility.

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.

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.

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

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.

Establishment of age- and sex-adjusted reference data for hand bone mass and investigation of hand bone loss in patients with rheumatoid arthritis treated in clinical practice: an observational study from the DANBIO registry and the Copenhagen Osteoarthritis Study

Background

Rheumatoid arthritis is characterised by progressive joint destruction and loss of periarticular bone mass. Hand bone loss (HBL) has therefore been proposed as an outcome measure for treatment efficacy. A definition of increased HBL adjusted for age- and sex-related bone loss is lacking. In this study, we aimed to: 1) establish reference values for normal hand bone mass (bone mineral density measured by digital x-ray radiogrammetry (DXR-BMD)); and 2) examine whether HBL is normalised in rheumatoid arthritis patients during treatment with tumour necrosis factor alpha inhibitors (TNFI).

Methods

DXR-BMD was measured from hand x-rays in a reference cohort (1485 men/2541 women) without arthritis randomly selected from an urban Danish population. Sex- and age-related HBL/year was estimated. DXR-BMD was measured in rheumatoid arthritis patients (n = 350: at start of TNFI, and ~2 years after TNFI start), of which 135 patients had three x-rays (~2 years prior to TNFI, at start of TNFI, and ~2 years after TNFI start). Individual HBL/year prior to and during TNFI was calculated and compared to reference values.

Results

Estimated HBL/year varied strongly with age and sex. Compared to the reference values, 75 % of 135 patients had increased HBL prior to TNFI treatment and 59 % had increased HBL during TNFI treatment (p = 0.17, Chi-squared). In 38 % (38/101) of patients with increased HBL, HBL was normalised during TNFI treatment, whereas 47 % (16/34) of patients with normal HBL prior to TNFI had increased HBL during TNFI treatment. In the 350 patients, increased HBL during TNFI was associated with time-averaged 28-joint disease activity score (odds ratio 1.69 (95 % Confidence Interval 1.34-2.15)/unit increase, p < 0.001), and patients in time-averaged remission had lower HBL than patients without remission (0.0032 vs. 0.0058 g/cm²/year; p < 0.001, Mann-Whitney).

Conclusions

We established age- and sex-specific reference values for DXR-BMD in a large cohort without arthritis. HBL was increased in the majority of rheumatoid arthritis patients initiating TNFI in clinical practice, and only normalised in a minority during TNFI.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-016-0952-y) contains supplementary material, which is available to authorized users.

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.

Is there a role for Digital X-ray Radiogrammetry as surrogate marker for radiological progression and imaging of structural integrity in rheumatoid arthritis?

Introduction

The established scoring techniques based on radiographs present limitations in the evaluation of structural integrity due to high effectiveness of innovative therapeutic strategies. The aim of this study was to evaluate the periarticular mineralisation as detected by Digital X-ray Radiogrammetry (DXR) as surrogate marker for structural integrity during the course of rheumatoid arthritis (RA).

Methods

11 centers throughout Germany contributed data of 94 patients with verified RA. The patients were treated with leflunomide or methotrexate during a mean observation period of 22 months. All patients underwent complete computerized calculations of bone mineral density (BMD) and metacarpal index (MCI) by DXR using digitized hand radiographs. The radiological assessment of disease progression was estimated by the Sharp Score.

Results

The Sharp Score revealed no significant change during the study period. DXR-BMD revealed minimal decrease of −1.4 % (leflunomide group) versus a higher reduction of −4.3 % (methotrexate group). Regarding DXR-MCI, a reduction of −2.2 % (leflunomide group) and −4.9 % (methotrexate group) was observed.

Conclusion

Quantitative data of hand bone mass estimated by the presented DXR-technique may be a complementary precise tool in the identification of RA-related radiographic changes and in the assessment of structural integrity.

IGFALS gene dosage effects on serum IGF-I and glucose metabolism, body composition, bone growth in length and width, and the pharmacokinetics of recombinant human IGF-I administration

CONTEXT

Acid labile subunit (ALS) deficiency, caused by IGFALS mutations, is a subtype of primary IGF-I deficiency (PIGFD) and has been associated with insulin resistance (IR) and osteopenia. Whether patients respond to recombinant human IGF-I (rhIGF-I) is unknown.

OBJECTIVE AND DESIGN

This study determined the 14-hour pharmacokinetic response of free and total IGF-I and IGF binding protein 3 (IGFBP-3) to a single sc dose of rhIGF-I (120 μg/kg) in four ALS-deficient patients, compared with severe PIGFD, moderate PIGFD, and controls. Intravenous glucose tolerance tests, fasting blood levels, dual-energy X-ray absorptiometry, peripheral quantitative computed tomography, and metacarpal radiogrammetry were performed in the four patients and 12 heterozygous family members.

RESULTS

IGF-I and IGFBP-3 increased above baseline (P < .05) for 2.5 hours, returning to baseline 7 hours after rhIGF-I injection. Mean (SD) IGF-I Z-score increased by 2.49 (0.90), whereas IGFBP-3 Z-score increased by 0.57 (0.10) only. IGF-I elimination rates in ALS deficiency were similar, but the IGF-I increment was lower than those for severe PIGFD. Significant gene dosage effects were found for all IGF-I peptides, height, forearm muscle size, and metacarpal width. Bone analysis showed that ALS deficiency creates a phenotype of slender bones with normal size-corrected density. Abnormal glucose handling and IR was found in three of four patients and 6 of 12 carriers.

CONCLUSIONS

These gene dosage effects demonstrate that one functional IGFALS allele is insufficient to maintain normal ALS levels, endocrine IGF-I action, full growth potential, muscle size, and periosteal expansion. Similar gene dosage effects may exist for parameters of IR. Despite similar IGF-I elimination compared with severe PIGFD, ALS-deficient patients cannot mount a similar response. Alternative ways of rhIGF-I administration should be sought.

Sexual maturation in Moroccan patients with juvenile idiopathic arthritis

Abnormal puberty is often reported in children suffering from many chronic diseases. Juvenile idiopathic arthritis (JIA) is the most common joint disorder in developing children. The aim of this study was to assess sexual maturation of Moroccan children with JIA and to compare the development of secondary sexual characteristics in children with JIA to children in the general population. Forty children with JIA and 74 healthy controls were included in a cross-sectional study. The diagnosis of JIA was made according to the criteria of the International League of Association of Rheumatology. Every child was examined for the development of genitalia as per criteria given by Tanner. The children with JIA were also divided into 3 groups: pre-puberty (stage 1), puberty (stages 2-3) and post-puberty (stage 4-5), and the association between puberty and cumulative dose of steroids, disease duration, disease activity, height, weight and age was investigated. Forty children with JIA were included (22 male, 18 female); the mean of age of the patients was 11 ± 4.23 years. Puberty in the patients (mean of tanner 2.43 ± 1.36) was lower than controls (2.55 ± 1.36). The prevalence of the children in prepuberty was of 15 (37.5 %) and 8 (20 %) in postpuberty. The prevalence of the children having a delayed puberty was of 6 (15 %) versus 1(1.4 %) in healthy controls (p = 0.005). There was an association between dose of corticosteroids, age at the administration of corticosteroids and the delayed puberty in boys (p = 0.009). In addition, there was no significant association in both sex between this poor puberty and duration of JIA (p = 0.45 in boys and p = 1.99 in girls) and its activity calculated by the DAS28 (p = 0.73 in boys and p = 1). Our study suggests that the puberty is retarded in Moroccan patients with JIA comparing to healthy children and that the dose of corticosteroid and the age at its administration may contribute to delayed puberty in boys.

Advances in bone imaging for osteoporosis

The diagnosis and management of osteoporosis have been improved by the development of new quantitative methods of skeletal assessment and by the availability of an increasing number of therapeutic options, respectively. A number of imaging methods exist and all have advantages and disadvantages. Dual-energy X-ray absorptiometry (DXA) is the most widely available and commonly utilized method for clinical diagnosis of osteoporosis and will remain so for the foreseeable future. The WHO 10-year fracture risk assessment tool (FRAX(®)) will improve clinical use of DXA and the cost-effectiveness of therapeutic intervention. Improved reporting of radiographic features that suggest osteoporosis and the presence of vertebral fracture, which are powerful predictors of future fractures, could increase the frequency of appropriate DXA referrals. Quantitative CT remains predominantly a research tool, but has advantages over DXA--allowing measurement of volumetric density, separate measures of cortical and trabecular bone density, and evaluation of bone shape and size. High resolution imaging, using both CT and MRI, has been introduced to measure trabecular and cortical bone microstructure. Although these methods provide detailed insights into the effects of disease and therapies on bone, they are technically challenging and not widely available, so they are unlikely to be used in clinical practice.

Comparison between amputation-induced demineralization and age-related bone loss using digital X-ray radiogrammetry

Digital X-ray radiogrammetry (DXR) is a computer-assisted automatic osteodensitometric tool. This study was performed to compare DXR measurements between bone changes following amputation trauma and age-related bone loss. Thirty-five men, who had undergone finger amputations, received a baseline examination and 2--3 serial measurements. As a second group, 215 males older than 70yr were enrolled. All patients obtained standardized hand radiographs. The following DXR parameters evaluating metacarpals were considered: cortical bone mineral density (DXR-BMD), cortical thickness (DXR-CT), metacarpal index (DXR-MCI), outer bone diameter (width; DXR-W), and inner medullary diameter (DXR-MD). In the amputation group, the DXR parameters showed an accentuated initial decrease between first and second measurements (DRX-BMD--12.7%, DXR-CT--14.2%, DXR-W--8.6%, DXR-MCI--6.1%; p<0.001) followed by a less pronounced reduction between second and third radiographs (DRX-BMD--0.5%, DXR-CT--1.5%, DXR-W--0.1%, DXR-MCI--1.3%). DXR-MD revealed a reduction of--3.6% (p<0.05) between first and second estimates and a non-significant increase (+1.1%) between second and third measurements. When compared with the second and third estimates in the amputation group, men older than 70yr presented lower DXR-BMD, DXR-CT, and DXR-MCI values (p<0.001), but larger metacarpal outer and inner bone diameters (DXR-W and DXR-MD; p<0.001). DXR-MD of the elderly men group was also more extended when compared with the baseline measurements of the amputation cohort (p<0.001). The early accentuated cortical bone loss and particularly the pronounced decrease of the outer bone width seem to be characteristic for amputation-induced osteoporosis, suggesting that this might be a distinct secondary osteoporosis entity. When compared with amputation-associated osteoporosis, where the bone loss occurs to a higher extent in the outer bone diameter than in the medullary cavity, the age-related bone changes lead more to an increase of the medullary diameter than of the outer bone width.

Radiogrammetry and radiographic absorptiometry

Metacarpal morphometry and radiogrammetry are the oldest methods for quantitative assessment of the skeleton. The historical aspects of these measurements are reviewed. Although they were inexpensive and widely available and provided useful research and epidemiologic information, they were labor intensive and imprecise. They were replaced with the current established methods of bone mineral densitometry. With the application of modern computer vision techniques, metacarpal morphometric analysis has been rejuvenated, with improvement in precision and evidence that the method can be applied to studies in adults and children. Evidence for limited normal reference data and the ability to predict future fractures in osteoporosis and reflect activity and predict outcomes in rheumatoid arthritis are presented.

Adalimumab therapy reduces hand bone loss in early rheumatoid arthritis: explorative analyses from the PREMIER study

OBJECTIVE

The effect of adalimumab on hand osteoporosis was examined and related to radiographic joint damage in the three treatment arms of the PREMIER study: adalimumab plus methotrexate, adalimumab and methotrexate monotherapy. Predictors of hand bone loss were also searched for.

METHODS

768 patients (537 fulfilled 2 years) with rheumatoid arthritis (RA) for less than 3 years, never treated with methotrexate, were included. Hand bone loss was assessed by digital x ray radiogrammetry (DXR) on the same hand radiographs scored with modified Sharp score at baseline, 26, 52 and 104 weeks. For DXR, metacarpal cortical index (MCI) was the primary bone measure.

RESULTS

At all time points the rate of percentage DXR-MCI loss was lowest in the combination group (-1.15; -2.16; -3.03) and greatest in the methotrexate monotherapy group (-1.42; -2.87; -4.62), with figures in between for the adalimumab monotherapy group (-1.33; -2.45; -4.03). Significant differences between the combination group and the methotrexate group were seen at 52 (p = 0.009) and 104 weeks (p<0.001). The order of hand bone loss across the three treatment arms was similar to the order of radiographic progression. Older age, elevated C-reactive protein and non-use of adalimumab were predictors of hand bone loss.

CONCLUSION

This study supports a similar pathogenic mechanism for hand bone loss and erosions in RA. The combination of adalimumab and methotrexate seems to arrest hand bone loss less effectively than radiographic joint damage. Quantitative measures of osteoporosis may thus be a more sensitive tool for assessment of inflammatory bone involvement in RA.

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 < or = 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.