Assessment of phalangeal bone loss in patients with rheumatoid arthritis by quantitative ultrasound

OBJECTIVE: Periarticular osteopenia is an early radiological sign of rheumatoid arthritis (RA). Quantitative ultrasound (QUS) devices have recently been shown to be useful for assessing osteoporosis. In this study the capability of a transportable and easy to use QUS device to detect skeletal impairment of the finger phalanges in patients with RA was investigated. METHODS: In a cross sectional study 83 women (30 controls, 29 with glucocorticosteroid (GC) treated RA, and 24 with GC treated vasculitis) were examined. QUS measurements were obtained at the metaphyses of the proximal phalanges II-V and directly at the proximal interphalangeal joints II-IV with a DBM Sonic 1200 (IGEA, Italy) QUS device. Amplitude dependent speed of sound (AD-SoS) was evaluated. In 23 of the patients with RA, hand radiographs were evaluated. RESULTS: Significant differences between patients with RA and the other groups were found for AD-SoS at both measurement sites. Compared with age matched controls, the AD-SoS of patients with RA was lowered by two and three standard deviations at the metaphysis and joint, respectively. Fingers of patients with RA without erosions (Larsen score 0-I) already had significantly decreased QUS values, which deteriorated further with the development of erosions (Larsen II-V). CONCLUSION: This study indicates that QUS is sensitive to phalangeal periarticular bone loss in RA. QUS is a quick, simple, and inexpensive method free of ionising radiation that appears to be suited to detection of early stages of periarticular bone loss. Its clinical use in the assessment of early RA should be further evaluated in prospective studies.     

Ultrasound and clinical evaluation of quadricipital tendon enthesitis in patients with psoriatic arthritis and rheumatoid arthritis

Enthesitis is an inflammatory lesion of the tendon, ligament and capsular insertions into the bone, and it is a fundamental element in the diagnosis of spondyloarthropathies. Sonography is the method of choice for studying periarticular soft tissues because it is capable of detecting both the early (oedema, thickening) and the late alterations (erosions and enthesophytes); it is also an inexpensive, biologically harmless and easily repeatable technique. The aim of this study was to compare the prevalence of quadricipital enthesitis in psoriatic arthritis (PsA) and rheumatoid arthritis (RA) patients, and to document any clinical and echostructural differences in this lesion between the two diseases. The results show that enthesitis is more frequent in PsA patients, more than half of whom are asymptomatic. Knee inflammation was found in the PsA patients with enthesitis regardless of the concomitant presence of joint effusion; none of the RA patients suffered from enthesitis alone. Quadricipital enthesitis is more frequent in male patients. There was no significant correlation between the presence of peripatellar psoriatic lesions and enthesitis. Sonographic examinations of patients with enthesitis revealed that those with RA had dominantly inflammatory lesions, whereas PsA patients also showed major new bone deposition. Received: 24 January 2001 / Accepted: 15 October 2001     

Psoriatic arthritis and imaging

Psoriatic arthritis (PsA) has historically been considered a milder rheumatic disease not yielding significant clinical damage. However, recent studies have shown that PsA can be deforming and debilitating and that joint damage can be severe. Traditionally, joint damage has been recorded using plain radiographs. Characteristic radiographic features of PsA include joint erosions, joint space narrowing, bony proliferation including periarticular and shaft periostitis, osteolysis including "pencil in cup" deformity and acro-osteolysis, ankylosis, spur formation, and spondylitis. New imaging modalities, including ultrasound, bone scanning, and magnetic resonance imaging may help in both diagnosis and follow up of patients with PsA. These new imaging techniques will with validation help detect early changes in the peripheral joints, the periarticular tissues, and the spinal structures in patients with PsA.     

Bone loss in unclassified polyarthritis and early rheumatoid arthritis is better detected by digital x ray radiogrammetry than dual x ray absorptiometry: relationship with disease activity and radiographic outcome

OBJECTIVE: To compare changes in regional bone mineral density (BMD) of the metacarpal joints measured by dual x ray absorptiometry (DXA) and digital x ray radiogrammetry (DXR) in relation to disease activity and radiographic outcome in a two year follow up study of patients with early RA and unclassified polyarthritis. PATIENTS AND METHODS: 72 patients with symmetrically swollen and tender second and third metacarpophalangeal or proximal interphalangeal joints for at least four weeks and less than two years were included. 51 patients fulfilled the ACR criteria for RA. 21 patients had unclassified polyarthritis. The patients with RA were divided into groups according to mean disease activity, average glucocorticoid dose, and MRI and x ray detected bone erosions in the hands. Clinical and biochemical measurements were made every month and an x ray examination of the hands and BMD of the metacarpal joints every six months. RESULTS: DXR BMD decreased significantly only in patients with RA from month 6 and was associated with the mean disease activity. Patients with RA and erosive as well as non-erosive disease showed a significant decrease in the rate of bone loss, greatest in those with erosive disease. No changes in BMD measured by DXA were seen in any patient group. CONCLUSION: DXR is a useful measure of the destructive disease activity in patients with RA and unclassified polyarthritis, providing valuable information about bone changes associated with disease activity and erosive disease in early RA. DXR is better than DXA for detecting and monitoring periarticular osteoporosis of the metacarpal bone.     

Psoriatic arthritis: imaging techniques

Imaging techniques to assess psoriatic arthritis (PsA) include radiography, ultrasonography (US), magnetic resonance imaging (MRI), computed tomography (CT) and bone scintigraphy. The radiographic hallmark of PsA is the combination of destructive changes (joint erosions, tuft resorption, osteolysis) with bone proliferation (including periarticular and shaft periostitis, ankylosis, spur formation and non-marginal syndesmophytes). US has an increasing important role in the evaluation of PsA. In fact, power Doppler US is useful mainly for its ability to assess musculoskeletal (joints, tendons, entheses) and cutaneous (skin and nails) involvement, to monitor efficacy of therapy and to guide steroid injections at the level of inflamed joints, tendon sheaths and entheses. MRI allows direct visualization of inflammation in peripheral and axial joints, and peripheral and axial entheses, and has dramatically improved the possibilities for early diagnosis and objective monitoring of the disease process in PsA. MRI has allowed explaining the relationships among enthesitis, synovitis and osteitis in PsA, supporting a SpA pattern of inflammation where enthesitis is the primary target of inflammation. CT has little role in assessment of peripheral joints, but it may be useful in assessing elements of spine disease. CT accuracy is similar to MRI in assessment of erosions in sacroiliac joint involvement, but CT is not as effective in detecting synovial inflammation. Bone scintigraphy lacks specificity and is now supplanted with US and MRI techniques.     

Ultrasound and clinical evaluation of quadricipital tendon enthesitis in patients with psoriatic arthritis and rheumatoid arthritis

Enthesitis is an inflammatory lesion of the tendon, ligament and capsular insertions into the bone, and it is a fundamental element in the diagnosis of spondyloarthropathies. Sonography is the method of choice for studying periarticular soft tissues because it is capable of detecting both the early (oedema, thickening) and late alterations (erosions and enthesophytes); it is also an inexpensive, biologically harmless and easily repeatable technique. The aim of this study was to compare the prevalence of quadricipital enthesitis in psoriatic arthritis (PsA) and rheumatoid arthritis (RA) patients, and to document any clinical and echostructural differences in this lesion between the two diseases. The results show that enthesitis is more frequent in PsA patients, more than half of whom are asymptomatic. Knee inflammation was found in the PsA patients with enthesitis regardless of the concomitant presence of joint effusion; none of the RA patients suffered from enthesitis alone. Quadricipital enthesitis is more frequent in male patients. There was no significant correlation between the presence of peripatellar psoriatic lesions and enthesitis. Sonographic examinations of patients with enthesitis revealed that those with RA had predominantly inflammatory lesions, whereas PsA patients also showed major new bone deposition. Received: 24 January 2001 / Accepted: 16 January 2002     

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.     

Measurement of hand bone mineral density in early rheumatoid arthritis using dual energy X‐ray absorptiometry

Aims: The earliest radiological change in rheumatoid arthritis (RA) is periarticular osteopenia, which occurs prior to the appearance of erosions and clinically apparent deformities. The aim of the study was to measure periarticular bone mineral density (BMD) in the hands of patients with early RA, using dual energy X‐ray absorptiomentry (DEXA) and to correlate this with markers of disease activity and radiological progression. Methods: The study population (n = 50) of patients with RA of < 3 years duration underwent measurement of BMD of the non‐dominant hand, femoral neck and lumbar spine and clinical assessment at baseline, 6 and 12 months. Hand radiographs were performed at baseline and 12 months. Thirty age‐ and sex‐matched controls also underwent measurement of BMD of the non‐dominant hand, femoral neck and lumbar spine. Results: Hand BMD correlated strongly with sex, height, weight and lumbar and femoral neck BMD in both RA subjects and controls. Baseline hand BMD in RA subjects correlated with baseline serum C‐reactive protein (r = ?0.36, P = 0.01) and 12‐month radiographic score (r = 0.36, P = 0.02). There were small non‐significant decreases in hand, femoral neck and lumbar spine BMD over the 12‐month period. Conclusion: Hand BMD measurement using DEXA is a reproducible, well‐tolerated procedure that warrants further investigation as a component of routine assessment in early RA.     

Association of apolipoprotein E polymorphism with bone mineral density in postmenopausal women with rheumatoid arthritis

SIR, Pathological bone loss can occur by marginal erosions,juxta-articular osteoporosis and generalized osteoporosis inrheumatoid arthritis (RA) [1]. Several studies demonstratedthat these different types of bone involvement are similarlymediated by receptor activator of nuclear factor B ligand (RANKL),a factor stimulating osteoclast differentiation [2, 3]. Therefore,generalized osteoporosis has been suggested as a risk factorfor severe joint destruction in RA. In fact, joint erosionsrelated to generalized osteoporosis and high Larsen scores associatedstrongly with bone mineral density (BMD) reduction have beenfound in patients with     

Serum concentrations of formation (PINP) and resorption (Ctx) bone turnover markers in rheumatoid arthritis

Joint inflammation in rheumatoid arthritis (RA) induces local periarticular osteoporosis. Generalised bone mineral density (BMD) decrease concerns approximately 50% of rheumatic patients. Both types of bone mass depletion can issue from cytokine-induced (TNF-α, IL-1, IL-6) osteoclasts’ activation, osteoprotegerin and its ligand’s (RANKL) function disorders, patients’ immobilisation and glucocorticosteroid (GCS) intake, as well as from hormonal alterations in postmenopausal women, predominate among RA individuals. The aim of the study was to compare serum concentrations of marker of bone formation—serum aminoterminal propeptide of type I collagen (PINP), and bone resorption, carboxy (C) terminal telopeptide (Ctx), bone turnover markers in RA and osteoarthritis (OA) patients and in RA groups of different disease activity, different degree of joint damage and the history of GCS intake. A total of 50 RA female patients and 50 women with knee OA were included in the study. Blood for morphology and biochemistry laboratory tests was taken. Joint X-rays to establish OA and RA diagnosis and the degree of RA progression, as well as DEXA BMD measurements were performed. PINP and Ctx concentrations were assessed. In RA patients the number of swollen and painful joints, the duration of morning stiffness, visual analogue scale values and Waaler–Rose’s test activity were recorded. The Disease Activity Index (DAS 28) was counted from the appropriate formula. No differences in bone turnover markers’ concentrations were noted neither between RA and OA patients nor between the RA group when compared to the one without the history of GCS use. Bone turnover markers’ concentrations in RA were proportional to the number of swollen and painful joints. However, no correlation was found between the markers’ concentrations and RA activity assessed by DAS 28 or by laboratory means. Ctx concentrations were higher in patients at II degree joint damage according to Larsen and Dale’s than at more advanced stages. Ctx concentrations decreased with the disease duration. Serum morphogenesis and resorption markers’ concentrations change in course of RA indicating the decrease in bone metabolic activity with the disease duration and progression. High RA activity and severity correlate with increased markers’ levels—the resorption one. The influence of GCS on bone metabolism in RA requires further study.     

Interobserver agreement in ultrasonography of the finger and toe joints in rheumatoid arthritis

OBJECTIVE: To evaluate the interobserver agreement of ultrasonographic assessment of finger and toe joints in patients with rheumatoid arthritis (RA) by 2 investigators with different medical backgrounds. METHODS: Ultrasonography and clinical examination were performed on 150 small joints of 30 patients with active RA. A General Electric LOGIQ 500 ultrasound unit with a 7-13-MHz linear array transducer was used. In each patient, 5 preselected small joints (second and third metacarpophalangeal, second proximal interphalangeal, first and second metatarsophalangeal) were examined independently on the same day by 2 ultrasound investigators (an experienced musculoskeletal radiologist and a rheumatologist with limited ultrasound training). Joint effusion, synovial thickening, bone erosions, and power Doppler signal were evaluated in accordance with an introduced 4-grade semiquantitative scoring system, on which the investigators had reached consensus prior to the study. RESULTS: Exact agreement between the 2 observers was seen in 91% of the examinations with regard to bone erosions, in 86% with regard to synovitis, in 79% with regard to joint effusions, and in 87% with regard to power Doppler signal assessments. Corresponding intraclass correlation coefficient values were 0.78, 0.81, 0.61, and 0.72, respectively, while unweighted kappa values were 0.68, 0.63, 0.48, and 0.55, respectively. Ultrasonography showed signs of inflammation in 94 joints, while clinical assessment revealed tenderness and/or swelling in 64 joints. CONCLUSION: An experienced radiologist and a rheumatologist with limited ultrasound training achieved high interobserver agreement rates for the identification of synovitis and bone erosions, using an introduced semiquantitative scoring system for ultrasonography of finger and toe joints in RA. Signs of inflammation were more frequently detected with ultrasound than with clinical examination. Ultrasonography may improve the assessment of RA patients by radiologists and rheumatologists.     

Effects of rheumatoid arthritis on bone

The effects of rheumatoid arthritis on bone include structural joint damage (erosions) and osteoporosis. The latter may lead to increased risk for fractures, which are associated with increased morbidity and mortality. Osteoporosis in rheumatoid arthritis is characterized by a complexity of risk factors, including primary osteoporosis risk factors in addition to inflammation, immobilization, and use of corticosteroids. Quantitative assessment of periarticular and generalized bone loss in rheumatoid arthritis may be reliable indicators of future disease course and potential response variables in intervention studies. The osteoclast cell in rheumatoid arthritis plays a crucial role in the development of erosions and periarticular and generalized osteoporosis, suggested to be mediated through the osteoprotegerin/receptor activator of Nuclear Factor (NF)-kappabeta/receptor activator of NF-kappabeta ligand signaling system. Based on an improved understanding of this biology, new treatment opportunities exist.     

Patients with rheumatoid arthritis are more tender than those with psoriatic arthritis.

Articular and nonarticular tenderness was examined in 51 patients with rheumatoid arthritis (RA) and 50 patients with psoriatic arthritis (PsA) by scored palpation and dolorimeter readings. Fifty-seven percent of patients with RA had 10 or more tender fibrositic points vs 24% of patients with PsA (p = 0.0008). Thresholds of tenderness measured by dolorimetry of 6 fibrositic point sites were 3.97 (1.99) [mean (SD)] for RA vs 5.95 (2.28) for PsA (p less than 0.0001). Thresholds over actively inflamed joints were 4.19 (1.53) for RA vs 6.78 (2.55) for PsA (p less than 0.0001). In both RA and PsA, fibrositic sites were more tender than actively inflamed joints (p less than 0.0001). Nonarticular control sites were also more tender in subjects with RA with dolorimeter thresholds at 5.99 (1.96) in RA vs 7.58 (1.60) in PsA (p less than 0.0001). These data demonstrate that actively inflamed joints, fibrositic and control nonarticular sites were all more tender in patients with RA than PsA. Both groups were similar in their disease duration and clinical assessments of joint inflammation and damage. We suggest that there may be a disease specific diffuse increase in tenderness in patients with RA, which is not related to joint inflammation. Similarly, the severity of articular inflammation may be underestimated in subjects with PsA.     

Evidence for a different anatomic basis for joint disease localization in polymyalgia rheumatica in comparison with rheumatoid arthritis

OBJECTIVE: The anatomic basis for joint disease localization in polymyalgia rheumatica (PMR) is poorly understood. This study used contrast-enhanced and fat suppression magnetic resonance imaging (MRI) to evaluate the relationship between synovial and extracapsular inflammation in PMR and early rheumatoid arthritis (RA). METHODS: Ten patients with new-onset PMR and 10 patients with early RA underwent dynamic contrast-enhanced MRI and conventional MRI of affected metacarpophalangeal (MCP) joints. Synovitis and tenosynovitis were calculated based on the number of enhancing voxels, initial rate of enhancement, and maximal enhancement of gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA). Periarticular bone erosion and bone edema were scored according to the OMERACT (Outcome Measures in Rheumatology Clinical Trials) scoring system in both groups. The degree of extracapsular Gd-DTPA enhancement was assessed in both conditions using semiquantitative scoring. RESULTS: No significant differences were seen in the volume of synovitis (P = 0.294), degree of flexor tenosynovitis (P = 0.532), periarticular erosions (P = 0.579), or degree of bone edema (P = 0.143) between RA and PMR joints. However, despite comparable degrees of synovitis, the proportion of MCP joints showing extracapsular enhancement was higher in the PMR group (100%) than in the RA group (50%) (P = 0.030). One PMR patient, but none of the RA patients, had bone edema at the capsular insertion. CONCLUSION: Despite degrees of synovitis and tenosynovitis comparable with those in RA, PMR-related hand disease is associated with prominent extracapsular changes, suggesting that inflammation in these tissues is more prominent than joint synovitis, which is common in both conditions. This suggests that the anatomic basis for joint disease localization differs between RA and PMR.     

Serum levels of tissue inhibitor of metalloproteinase-1 and periarticular bone loss in early rheumatoid arthritis

We investigated the relationship between disease activity, serum biological mediators of joint damage, and periarticular bone loss in inflammatory arthritis. Patients with early inflammatory arthritis were recruited from a dedicated early arthritis clinic. At the time of recruitment, all had clinical evidence of synovitis. Patients were assessed at baseline and at 1-year follow-up. Periarticular and axial bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry. Serum levels of matrix metalloproteinase 1 and tissue inhibitor of metalloproteinases 1 (TIMP-1) were measured by enzyme-linked immunosorbent assay. A total 38 patients were included in the study. Twenty had rheumatoid arthritis (RA) and 18 had a seronegative spondylarthropathy (SpA). At baseline, periarticular hand BMD measurements were similar in RA and SpA. At 1 year, the mean periarticular hand BMD was significantly lower in RA (p < 0.05). Significant inverse correlations between both the Ritchie articular index and C-reactive protein levels and the change in periarticular hand BMD at 1 year were observed in RA (r = −0.792, p < 0.001 and r = −0.478, p = 0.045, respectively). Baseline TIMP-1 levels correlated with the change in periarticular hand BMD at 1 year in RA (r = 0.519, p = 0.02). At 1 year, radiographic measures of joint damage were highest in RA. Inverse correlations between the change in periarticular hand BMD and the changes in erosion score (r = −0.90, p = 0.04) were observed in patients demonstrating significant periarticular bone loss. Persistent disease activity was associated with increased periarticular bone loss in the hands in patients with RA, consistent with synovitis-mediated periarticular bone loss. The correlation between baseline TIMP-1 levels and periarticular bone loss over 1 year suggests that TIMP-1 may have utility as a biomarker of periarticular bone loss in early RA.     

The effect of circulating nitric oxide level on axial bone mineral density in postmenopausal Turkish women with rheumatoid arthritis: a preliminary report

The aim is to investigate the differences in the circulating nitric oxide (NO) levels of rheumatoid arthritis (RA) patients, healthy controls and osteoporotic (OP) patients. We also examined whether the circulating NO levels may be correlated with bone mineral density (BMD) in RA patients. Forty-five patients with RA, 30 healthy women and 30 osteoporotic patients were recruited from the outpatient clinic. All the subjects were female and postmenopausal. Serum NO levels were measured (Nitrite/Nitrate, calorimetric method 1746081, Roche diagnostics, Mannheim, Germany) and BMD was measured at the spine and hip using dual energy X-Ray absorbtiometry (DEXA, Norland XR-46). Height and weight were measured and body mass index was calculated. Circulating NO levels were significantly higher in RA patients than other groups. Moreover, the RA group showed significantly higher BMD at lumbar spine and femoral neck regions compared to osteoporotic patients. However, the RA group showed significantly lower BMD at all sites than the controls. There was no correlation between circulating NO levels and BMD in all groups. We suggest that, unlike postmenopausal osteoporosis, inflammation induced osteoporosis is associated with RA is characterised by relatively preserved bone mass at the axial bone regions, and circulating NO levels as a parameter or determinant of inflammation are not correlated with axial BMD in RA patients.     

Bone erosions and bone marrow edema as defined by magnetic resonance imaging reflect true bone marrow inflammation in rheumatoid arthritis

OBJECTIVE: To investigate the pathologic nature of features termed "bone erosion" and "bone marrow edema" (also called "osteitis) on magnetic resonance imaging (MRI) scans of joints affected by rheumatoid arthritis (RA). METHODS: RA patients scheduled for joint replacement surgery (metacarpophalangeal or proximal interphalangeal joints) underwent MRI on the day before surgery. The presence and localization of bone erosions and bone marrow edema as evidenced by MRI (MRI bone erosions and MRI bone marrow edema) were documented in each joint (n=12 joints). After surgery, sequential sections from throughout the whole joint were analyzed histologically for bone marrow changes, and these results were correlated with the MRI findings. RESULTS: MRI bone erosion was recorded based on bone marrow inflammation adjacent to a site of cortical bone penetration. Inflammation was recorded based on either invading synovial tissue (pannus), formation of lymphocytic aggregates, or increased vascularity. Fat-rich bone marrow was replaced by inflammatory tissue, increasing water content, which appears as bright signal enhancement on STIR MRI sequences. MRI bone marrow edema was recorded based on the finding of inflammatory infiltrates, which were less dense than those of MRI bone erosions and localized more centrally in the joint. These lesions were either isolated or found in contact with MRI bone erosions. CONCLUSION: MRI bone erosions and MRI bone marrow edema are due to the formation of inflammatory infiltrates in the bone marrow of patients with RA. This emphasizes the value of MRI in sensitively detecting inflammatory tissue in the bone marrow and demonstrates that the inflammatory process extends to the bone marrow cavity, which is an additional target structure for antiinflammatory therapy.     

Prospective 7 year follow up imaging study comparing radiography, ultrasonography, and magnetic resonance imaging in rheumatoid arthritis finger joints

OBJECTIVE: To perform a prospective long term follow up study comparing conventional radiography (CR), ultrasonography (US), and magnetic resonance imaging (MRI) in the detection of bone erosions and synovitis in rheumatoid arthritis (RA) finger joints. METHODS: The metacarpophalangeal and proximal interphalangeal joints II-V (128 joints) of the clinically dominant hand of 16 patients with RA were included. Follow up joint by joint comparisons for erosions and synovitis were made. RESULTS: At baseline, CR detected erosions in 5/128 (4%) of all joints, US in 12/128 (9%), and MRI in 34/128 (27%). Seven years later, an increase of joints with erosions was found with CR (26%), US (49%) (p<0.001 each), and MRI (32%, NS). In contrast, joint swelling and tenderness assessed by clinical examination were decreased at follow up (p = 0.2, p<0.001). A significant reduction in synovitis with US and MRI (p<0.001 each) was seen. In CR, 12 patients did not have any erosions at baseline, while in 10/12 patients erosions were detected in 25/96 (26%) joints after 7 years. US initially detected erosions in 9 joints, of which two of these joints with erosions were seen by CR at follow up. MRI initially found 34 erosions, of which 14 (41%) were then detected by CR. CONCLUSION: After 7 years, an increase of bone erosions was detected by all imaging modalities. In contrast, clinical improvement and regression of synovitis were seen only with US and MRI. More than one third of erosions previously detected by MRI were seen by CR 7 years later.     

Validated measurement of periarticular bone mineral density at the knee joint by dual energy x ray absorptiometry

OBJECTIVE: The association of inflammatory arthritis with loss of periarticular bone mineral density (BMD) has been well established. However, changes in bone density cannot be quantified by conventional radiography. This study aimed at developing a new technique for measurement of periarticular bone density at the knee joint by dual energy x ray absorptiometry (DXA) and assessing the precision of this technique for selected areas around the knee. METHODS: To validate this technique for bone density assessment in both patient and control subjects, knee joints from healthy subjects and patients with inflammatory arthritis were selected for study. Posteroanterior (PA) and lateral scans of both knees were acquired with the Hologic 4500 elite bone densitometer. Each scan was repeated three times, with repositioning between scans. Knee scans were obtained with the forearm software and evaluated by subregion analysis. Seven femoral and seven tibial subregions of interest (ROIs) were selected on PA scans. Six ROIs were selected on lateral scans. Precision was determined for each ROI selected. RESULTS: 14 knee joints were studied in each group. Precision, expressed as percentage coefficient of variation (CV%), varied widely between subregions. PA scans were most appropriate for measurement of femoral bone density (CV% = 1.89-2.64%), whereas the best value obtained for ROIs within the tibia was on the lateral scan, where CV% for measurement of the proximal 5 mm was 2.67% in the patient group. CV% for BMD of the patella was excellent at 0.84% in the patient group. CONCLUSION: This new application of DXA can be used to measure periarticular bone density at the knee joint. Regions within the distal femur and patella have been identified as the optimal areas to study     

Tumour necrosis factor-related apoptosis-inducing ligand and osteoprotegerin serum levels in psoriatic arthritis

OBJECTIVES: The degree of bone loss in patients with psoriatic arthritis (PsA) has not been well-defined. We tested the hypothesis, whether serum levels of tumour necrosis factor-related apoptosis-inducing ligand (TRAIL), a pro-apoptotic cytokine and osteoprotegerin (OPG), an anti-osteoclastic cytokine, are associated with changes in biochemical markers of bone turnover or bone mineral density (BMD) in patients with PsA. METHODS: In a cross-sectional study, we evaluated biochemical markers of bone turnover, BMD and serum levels of TRAIL and OPG in 116 patients with PsA (mean age: 52+/-13 yrs). RESULTS: In patients with PsA, osteopenia was present in one-third of women and men, while osteoporosis was more frequent in men (10.2%) than in women (1.75%). Serum levels of TRAIL were significantly higher in patients with PsA (66.1+/-45.3 pmol/l) compared with controls (50.0+/-20.1 pmol/l, P<0.01), whereas OPG serum levels were not different. There were no associations between TRAIL or OPG serum levels with BMD and biochemical markers of bone turnover. However, TRAIL serum levels were associated with C-reactive protein (CRP) levels (R = 0.201, P<0.05), whereas OPG serum levels were associated with the erythrocyte sedimentation rate (R=0.215, P<0.05). CONCLUSION: In summary, BMD is decreased in one-third of patients with PsA, and predominantly men with PsA suffer from osteoporosis. While TRAIL serum levels are increased in PsA and correlated with CRP levels, neither TRAIL nor OPG serum levels are correlated with BMD or markers of bone metabolism.