I.K. Haugen

Prevalence, incidence and progression of hand osteoarthritis in the general population: the Framingham Osteoarthritis Study

Objectives To describe the prevalence and longitudinal course of radiographic, erosive and symptomatic hand osteoarthritis (HOA) in the general population. Methods Framingham osteoarthritis (OA) study participants obtained bilateral hand radiographs at baseline and 9-year follow-up. The authors defined radiographic HOA at joint level as Kellgren–Lawrence grade (KLG)≥2, erosive HOA as KLG≥2 plus erosion and symptomatic HOA as KLG≥2 plus pain/aching/stiffness. Presence of HOA at individual level was defined as ≥1 affected joint. The prevalence was age-standardised (US 2000 Population 40–84 years). Results Mean (SD) baseline age was 58.9 (9.9) years (56.5% women). The age-standardised prevalence of HOA was only modestly higher in women (44.2%) than men (37.7%), whereas the age-standardised prevalence of erosive and symptomatic OA was much higher in women (9.9% vs 3.3%, and 15.9% vs 8.2%). The crude incidence of HOA over 9-year follow-up was similar in women (34.6%) and men (33.7%), whereas the majority of those women (96.4%) and men (91.4%) with HOA at baseline showed progression during follow-up. Incident metacarpophalangeal and wrist OA were rare, but occurred more frequently and from an earlier age in men than women. Development of erosive disease occurred mainly in those with non-erosive HOA at baseline (as opposed to those without HOA), and was more frequent in women (17.3%) than men (9.6%). Conclusions The usual female predominance of prevalent and incident HOA was less clear for radiographic HOA than for symptomatic and erosive HOA. With an ageing population, the impact of HOA will further increase.

MRI-based semiquantitative scoring of joint pathology in osteoarthritis

The use of MRI techniques to investigate tissue pathology has become increasingly widespread in osteoarthritis (OA) research. Semiquantitative assessment of the joints by expert interpreters of MRI data is a powerful tool that can increase our understanding of the natural history of this complex disease. Several reliable and validated semiquantitative scoring systems now exist and have been applied to large-scale, multicentre, cross-sectional and longitudinal observational epidemiological studies. Such approaches have advanced our understanding of the associations of different tissue pathologies with pain and improved the definition of joint alterations that lead to disease progression. Semiquantitative MRI outcome measures have also been applied in several clinical trials in OA. Indeed, interest in MRI-based semiquantitative scoring systems has led to the development of several novel scoring systems that can be applied to different joints: a knee synovitis scoring system based on contrast-enhanced MRI; the MRI Osteoarthritis Knee Score (MOAKS); the Hip Osteoarthritis MRI Score (HOAMS); and the Oslo Hand Osteoarthritis MRI score (OHOA-MRI). Although these new scoring systems offer theoretical advantages over pre-existing systems, whether they offer actual superiority with regard to reliability, responsiveness and validity remains to be seen.

Associations between MRI-defined synovitis, bone marrow lesions and structural features and measures of pain and physical function in hand osteoarthritis

Objectives To explore associations between MRI features and measures of pain and physical function in hand osteoarthritis (OA). Methods Eighty-five patients (77 women) with mean (SD) age of 68.8 (5.6) years underwent contrast-enhanced MRI of the interphalangeal joints (dominant hand) and clinical joint assessment. One investigator read the MRIs for presence/severity of osteophytes, joint space narrowing, erosions, bone attrition, cysts, malalignment, synovitis, flexor tenosynovitis, bone marrow lesions (BMLs) and ligament discontinuity according to the proposed Oslo hand OA MRI score. Pain and physical function were assessed by joint palpation (tenderness yes/no), self-reported questionnaires (Australian/Canadian (AUSCAN) hand index, Functional Index of hand osteoarthritis (FIHOA), Arthritis Impact Measurement Scale-2 (AIMS-2) hand/finger) and grip strength. Logistic regression with generalised estimating equations was used to explore associations between the presence of MRI features and joint tenderness, and linear regression for associations between the burden of MRI abnormalities and patient-reported outcomes and grip strength (adjusted for age and sex). MRI features with p<0.25 were introduced into a multivariate model. The final model included features with p≤0.10 (backward selection). Results MRI-defined moderate/severe synovitis (OR=2.4; p<0.001), BMLs (OR=1.5; p=0.06), erosions (OR=1.4; p=0.05), attrition (OR=2.5; p<0.001) and osteophytes (OR=1.4; p=0.10) were associated with joint tenderness independently of each other (final model adjusted for age and sex). The sum score of MRI-defined attrition was associated with FIHOA (B=0.58; p=0.005), while the sum score of osteophytes was associated with grip strength (B=−0.39; p<0.001). No significant associations were found with AUSCAN pain/physical function or AIMS-2 hand/finger subscales. Conclusion MRI-defined synovitis, BMLs, erosions and attrition were associated with joint tenderness. Synovitis and BMLs may be targets for therapeutic interventions in hand OA.

Hand osteoarthritis and MRI: development and first validation step of the proposed Oslo Hand Osteoarthritis MRI score

Objectives MRI scoring systems for hand osteoarthritis (HOA) are currently not available. The present work proposes the Oslo HOA MRI (OHOA-MRI) score and examines the intrareader and inter-reader reliability. Methods Relevant HOA features were included in the initial version of the OHOA-MRI score after literature review and informal group discussions. After a training session and two calibration exercises (with three readers), features with low reliability and/or low prevalence were excluded, and feature definitions/gradings were improved. In the reliability exercise 3 readers independently evaluated MRI scans of distal interphalangeal (DIP) and proximal interphalangeal (PIP) joints in 10 patients with HOA according to the final proposed score. The reading was repeated after 1 week. Intraclass correlation coefficients (ICCs), percentage exact agreement/percentage close agreement (PEA/PCA) and smallest detectable difference were calculated. Results The final proposed OHOA-MRI score includes assessment of synovitis, flexor tenosynovitis, erosions, osteophytes (OPs), joint space narrowing (JSN) and bone marrow lesions (BMLs) on a 0–3 scale, and absence/presence of cysts, malalignment (frontal/sagittal plane), collateral ligaments (CLs) and BMLs at CL insertion sites. Inter-reader reliability was very good for synovitis, erosions, OPs, JSN, malalignment (frontal) and BMLs (ICCs ≥0.83, PCA ≥89%), and good for flexor tenosynovitis (ICC 0.64, PCA 80%) and CL presence (ICC 0.79, PEA 63%). Cysts, malalignment (sagittal) and BMLs at CL insertion sites showed high PEA (≥85%), but poor to moderate ICCs (0.00–0.59). Intrareader reliability was similar. The reliability was generally highest in PIP joints. Conclusions The proposed OHOA-MRI score could reliably assess HOA features. However, further validation is needed.

Hand osteoarthritis in relation to mortality and incidence of cardiovascular disease: data from the Framingham Heart Study

Objectives To study whether hand osteoarthritis (OA) is associated with increased mortality and cardiovascular events in a large community based cohort (Framingham Heart Study) in which OA, mortality and cardiovascular events have been carefully assessed. Methods We examined whether symptomatic (≥1 joint(s) with radiographic OA and pain in the same joint) and radiographic hand OA (≥1 joint(s) with radiographic OA without pain) were associated with mortality and incident cardiovascular events (coronary heart disease, congestive heart failure and/or atherothrombotic brain infarction) using Cox proportional hazards models. In the adjusted models, we included possible confounding factors from baseline (eg, metabolic factors, medication use, smoking/alcohol). We also adjusted for the number of painful joints in the lower limb and physical inactivity. Results We evaluated 1348 participants (53.8% women) with mean (SD) age of 62.2 (8.2) years, of whom 540 (40.1%) and 186 (13.8%) had radiographic and symptomatic hand OA, respectively. There was no association between hand OA and mortality. Although there was no significant relation to incident cardiovascular events overall or a relation of radiographic hand OA with events, we found a significant association between symptomatic hand OA and incident coronary heart disease (myocardial infarction/coronary insufficiency syndrome) (HR 2.26, 95% CI 1.22 to 4.18). The association remained after additional adjustment for pain in the lower limb or physical inactivity. Conclusions Symptomatic hand OA, but not radiographic hand OA, was associated with an increased risk of coronary heart disease events. The results suggest an effect of pain, which may be a possible marker of inflammation.

Comparison of features by MRI and radiographs of the interphalangeal finger joints in patients with hand osteoarthritis

Objectives To examine the construct validity of MRI in the detection of structural hand osteoarthritis features with conventional radiography (CR) as reference and explore the association between radiographic severity and MRI-defined pathology. Methods 106 hand osteoarthritis patients (97 women, mean age 68.9 years (SD 5.6)) had 1.0T contrast-enhanced MRI and CR of the dominant hand. The 2nd–5th interphalangeal joints were scored according to the preliminary Oslo hand osteoarthritis MRI score and Kellgren–Lawrence (KL) scale and Osteoarthritis Research Society International atlas for radiographs. The authors compared the number of joints with structural features by MRI and CR (Wilcoxon signed-rank test) and examined concordance at the individual joint level. The OR of MRI features in joints with doubtful (KL grade 1), mild (2) and moderate/severe (≥3) radiographic osteoarthritis was estimated by generalised estimating equations (KL grade 0 as reference). Results MRI detected approximately twice as many joints with erosions and osteophytes compared with CR (p<0.001), but identification of joint space narrowing, cysts and malalignment was similar. The sensitivity of MRI was very high for osteophytes (1.00) and erosions (0.95), while specificity was lower (0.22 and 0.63). The prevalence of most MRI features increased with radiographic severity, but synovitis was more frequent in joints with mild osteoarthritis (OR2.1, 95% CI 1.4 to 3.2) than in moderate/severe osteoarthritis (OR1.4, 95% CI 1.0 to 2.2). Conclusion MRI detected more osteophytes and erosions than CR, suggesting that erosive osteoarthritis may be more common than indicated by CR. Synovitis was most common in mild osteoarthritis. Whether this is due to burn-out of inflammation in late disease must be investigated further.

Ultrasound-detected inflammation predicts radiographic progression in hand osteoarthritis after 5 years

Objective To examine whether ultrasound predicts radiographic hand osteoarthritis (OA) progression after 5 years. Methods We included 78 participants (71 women, mean (SD) age 67.8 (5.2) years) from the Oslo Hand OA cohort with ultrasound examination (gray-scale (GS) synovitis and power Doppler (PD) signals) at baseline and conventional radiographs and clinical examination at baseline and 5-year follow-up. Radiographic progression was defined as an increase in global OA according to the Kellgren–Lawrence (KL) scale or progression of individual radiographic OA features. We examined whether baseline ultrasound features and clinical examination predicted radiographic progression using generalised estimating equations, adjusted for age, sex, body mass index and follow-up time. Results Radiographic progression occurred in 17.9% joints for KL, 12.1% for joint space narrowing, 11.7% for osteophytes and 4.5% for erosions. Ultrasound-detected inflammation predicted KL progression, and dose–response associations were observed for GS synovitis grade 1 (OR=2.8, 95% CI 1.8 to 4.2), grade 2 (OR=3.6, 95% CI 2.2 to 5.8) and grade 3 (OR=15.2, 95% CI 6.9 to 33.6), and for PD signal grade 1 (OR=2.9, 95% CI 1.2 to 6.8) and grades 2–3 (OR=12.0, 95% CI 3.5 to 41.0). Significant associations were also observed between ultrasound inflammation and progression of all individual radiographic features, and between clinical soft tissue swelling at baseline and radiographic progression. Conclusions Ultrasound-detected GS synovitis and PD signals were significantly associated with radiographic progression after 5 years. This study supports the use of ultrasound as a tool to detect patients with hand OA who are likely to progress.

Ultrasonographic assessment of osteophytes in 127 patients with hand osteoarthritis: exploring reliability and associations with MRI, radiographs and clinical joint findings

Objective To investigate the reliability of ultrasonographic assessment of osteophytes and explore the concordance of osteophytes detected by ultrasound, MRI, conventional radiography (CR) and clinical joint examination in patients with hand osteoarthritis (HOA). Methods The study included 127 HOA patients (116 women, mean age 68.6 years (SD 5.8)) with ultrasound, CR and clinical examination of both hands and MRI of dominant hand. Osteophytes were assessed by all imaging modalities on 0–3 scales, whereas clinical bony enlargement was assessed as absent/present. An ultrasound atlas of ostephytes was developed, and the intra and inter-reader reliability of scoring ultrasound osteophytes on still images using the atlas as reference was examined. The reliability for ultrasound readings was examined with κ and percentage exact agreement (PEA) and percentage close agreement (PCA), and the sensitivity, specificity and PEA/PCA of ultrasound was calculated in comparison with MRI, CR and clinical examination. Results Ultrasound had high sensitivity (0.83) and specificity (0.75) in detecting osteophytes compared with MRI, with excellent PCA (96.1%). Moderate/large osteophytes (grade 2–3) were demonstrated more often by ultrasound (n=401) than by MRI (n=288) in 851 interphalangeal joints. Ultrasound detected more osteophytes (53.2%) than CR (30.0%) and clinical examination (36.9%). Intra and inter-reader reliability of ultrasound was excellent (PEA >88%, PCA 100% and weighted kappa >0.91). Conclusion Ultrasound can reliably assess osteophytes in patients with HOA. Good agreement was found between osteophytes detected by ultrasound and MRI, while ultrasound was more sensitive than CR and clinical examination, which could be due to a multiplanar joint demonstration by ultrasound.

Iterative Development and Reliability of the OMERACT Hand Osteoarthritis MRI Scoring System

Objective. To develop and test the interreader reliability of the OMERACT Hand Osteoarthritis Magnetic Resonance Scoring System (HOAMRIS) for assessment of structural and inflammatory hand OA features in the interphalangeal joints. Methods. The HOAMRIS was developed through an iterative process. Selection of features and their scaling was agreed upon through consensus by members of the OMERACT Magnetic Resonance Imaging (MRI) Task Force, using the Oslo Hand Osteoarthritis (OA) MRI Score system as a template. Two reliability exercises were performed, in which 6 and 4 readers participated, respectively. After the first exercise, an atlas was developed and used in the second exercise to facilitate reading. In each exercise, readers independently scored 8 MRI scans from the Oslo Hand OA cohort (coronal/axial short-tau inversion recovery and coronal/axial/sagittal T1-weighted fat-suppressed pre-/post-Gadolinium images). Interreader reliability was assessed by intraclass correlation coefficients (ICC), percentage exact and close agreement (PEA/PCA). Results. The preliminary OMERACT HOAMRIS included assessment of synovitis, erosive damage, cysts, osteophytes, cartilage space loss, malalignment, and bone marrow lesions (BML), of which all were scored on a 0–3 scale for normal, mild, moderate, and severe (increments of 0.5 for synovitis, erosive damage, and BML). In the first exercise, most features showed good to very good ICC values (0.64–0.94), except synovitis (0.34). In the second exercise using the atlas, the ICC values were > 0.74 for all MRI features, and the PEA/PCA values were higher than in the first exercise. Conclusion. A preliminary HOAMRIS with good to very good interreader reliability was developed. Longitudinal studies are needed to assess its sensitivity to change.

Bone mineral density in patients with hand osteoarthritis compared to population controls and patients with rheumatoid arthritis

Objectives: Several studies have revealed increased bone mineral density (BMD) in patients with knee or hip osteoarthritis, but few studies have addressed this issue in hand osteoarthritis (HOA). The aims of this study were to compare BMD levels and frequency of osteoporosis between female patients with HOA, rheumatoid arthritis (RA) and controls aged 50–70 years, and to explore possible relationships between BMD and disease characteristics in patients with HOA. Methods: 190 HOA and 194 RA patients were recruited from the respective disease registers in Oslo, and 122 controls were selected from the population register of Oslo. All participants underwent BMD measurements of femoral neck, total hip and lumbar spine (dual-energy x ray absorptiometry), interview, clinical joint examination and completed self-reported questionnaires. Results: Age-, weight- and height-adjusted BMD values were significantly higher in HOA versus RA and controls, the latter only significant for femoral neck and lumbar spine. The frequency of osteoporosis was not significantly different between HOA and controls, but significantly lower in HOA versus RA. Adjusted BMD values did not differ between HOA patients with and without knee OA, and significant associations between BMD levels and symptom duration or disease measures were not observed. Conclusion: HOA patients have a higher BMD than population-based controls, and this seems not to be limited to patients with involvement of larger joints. The lack of correlation between BMD and disease duration or severity does not support the hypothesis that higher BMD is a consequence of the disease itself.