Ultrasound response to tofacitinib in patients with rheumatoid arthritis: Data from a multicenter 24 weeks prospective study

Background

Treatment of rheumatoid arthritis (RA) should aim at full remission. Ultrasonography (US) might have an added value to clinical examination in assessing disease activity of RA. In this study we evaluated the ultrasound response, next to clinical and laboratory response, in RA patients treated with tofacitinib (TOF).

Methods

In this observational multicenter study, patients received TOF 5 mg twice daily, with or without the contemporary use of methotrexate or other conventional DMARD, for 24 weeks. All patients underwent clinical, laboratory and US examinations of 40 sites among joints and tendons. Sonographers were blinded to clinical and laboratory parameters. Data were assessed at baseline, week 2, 4, 8, 12 and 24. For each patient we used two US joint scores (Gray Scale –GS–and power Doppler –PD– score), a 0–3 semi-quantitative scale for each joint and the EULAR-OMERACT US scoring system (combined GS and PD graded from 0 to 3). Besides, we calculated a tenosynovitis scores (GS and PD) according to the OMERACT score.

Results

Fifty-two RA patients completed the 6 months period study: mean disease duration 9.97 ± 8.75 years, baseline DAS28-CRP 4.9 ± 1.2, HAQ 1.4 ± 0.7, C-reactive protein (CRP 2.25 ± 3.11 mg/dl). Baseline joint (GS, PD and combined-US) and tendon US scores (GS and PD) were 23.5 ± 18.4, 22.7 ± 19.3, 25.7 ± 20.6, 10.5 ± 11.4 and 11.0 ± 12.0, respectively. US joint and tendon scores significantly reduced as early as T1 (week 2) examination as well as at week 4, 12 and 24, as compared to baseline values (p < 0.001 for all comparisons). Improvement of joint US scores (GS, PD and US-combined) correlated at T4 examination, with the reduction of serum CRP levels (rho 0.418, p = 0.036, rho 0.495, p = 0.004 and rho 0.454, p = 0.009, respectively). We did not find any correlation between the variations of DAS28-CRP and any US scores at any visits.

Conclusion

These results provide evidence that TOF treatment leads to early (2 weeks) and persistent reduction of US signs of inflammation both at tendon and joint level comparable to clinical improvement.

The EFSUMB Guidelines and Recommendations for Musculoskeletal Ultrasound - Part I: Extraarticular Pathologies

The first part of the guidelines and recommendations for musculoskeletal ultrasound, produced under the auspices of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB), provides information about the use of musculoskeletal ultrasound for assessing extraarticular structures (muscles, tendons, entheses, ligaments, bones, bursae, fasciae, nerves, skin, subcutaneous tissues, and nails) and their pathologies. Clinical applications, practical points, limitations, and artifacts are described and discussed for every structure. After an extensive literature review, the recommendations have been developed according to the Oxford Centre for Evidence-based Medicine and GRADE criteria and the consensus level was established through a Delphi process. The document is intended to guide clinical users in their daily practice.

Recommendations for the pragmatic use of ultrasound in rheumatoid arthritis by the GEISPER French group

OBJECTIVE

To develop recommendations for the appropriate use of ultrasound in the management of rheumatoid arthritis (RA) in routine practice based on data from the literature and of experts opinion.

METHODS

Based on a systematic literature review, a scientific committee decided on themes and relevant questions to draw up an initial draft of recommendations. These recommendations were submitted to a group of experts in ultrasound in rheumatic and musculoskeletal diseases using a Delphi method, which produced preliminary recommendations. These were submitted to an expanded group of ultrasound experts for relevance, comprehensibility and comprehensiveness. The level of agreement of the experts were recorded during a face-to-face meeting.

RESULTS

Following two rounds of the Delphi, a consensus was reached on three overarching principles, including definitions of joints, tendons and articular sites to be examined, and 10 recommendations. These recommendations underline the benefit of ultrasound for the diagnosis of RA in cases of inflammatory arthralgia or undifferentiated arthritis as well as in assessing the extent of initial structural and inflammatory damage. They also define the role of ultrasound during follow-up or when considering treatment reduction once clinical remission has been achieved. Lastly, they illustrate the utility of ultrasound in facilitating technical procedures.

CONCLUSION

These 10 consensus-based recommendations should harmonize and optimize clinical practice and thus improve the management of RA patients.

MRI and ultrasound of the hands and wrists in rheumatoid arthritis. I. Imaging findings

The management of patients with rheumatoid arthritis (RA) has rapidly evolved with the development of newer disease-modifying drugs and the recognition that long-term damage can be mitigated by an earlier and more-informed use of these medications. Historically, radiographs were the mainstay of imaging in RA patients, but radiographic joint narrowing and erosions are late and insensitive findings in the disease. MRI (with intravenous contrast agent) and ultrasound (with power Doppler interrogation) of the hands and wrists are able to demonstrate erosions earlier and with greater sensitivity than radiographs. More importantly, these imaging studies also depict synovitis and active soft-tissue inflammation, which represents a precursor to structural damage. Additionally, MRI can show inflammation within the bones (osteitis), which is proving to be the most important prognosticator of an aggressive disease course. Part I of this review discusses the imaging techniques, pitfalls, definitions, and comparative studies of MRI and ultrasound for identifying and quantifying erosions, synovitis, and osteitis. Part II will demonstrate how these imaging findings influence the clinical management of RA patients throughout their disease course, from presentation through clinical remission.

Patients with Rheumatoid Arthritis Were Associated with a Risk of Rotator Cuff Diseases

Rheumatoid arthritis (RA) commonly causes inflammation in the joints and periarticular structures. The association between RA and rotator cuff (RC) has been reported; however, epidemiological studies on RA and RC tendons are scant. Therefore, we investigated RC disease (RCD) risk and analyzed the effects of RA medication, steroids, and methotrexate, on the risk of RCD for patients with RA. We conducted a retrospective cohort study with a 6-year longitudinal follow-up in Taiwan. Patients who received RA diagnoses between 2004 and 2008 were enrolled in the study cohort. The non-RA control cohort comprised age- and sex-matched controls. Propensity score matching was used for other comorbidities and treatments. The hazard ratios (HRs) and adjusted HRs (aHRs) were estimated after confounders were adjusted for. Effects of steroid and methotrexate use on RCD risk were also analyzed. We enrolled 4521 RA patients (study cohort) and 22,605 matched controls. RCD incidence was 145 and 91 per 100,000 person-years in the RA and control cohorts, respectively. In the RA cohort, the crude HR for RCD was 1.62 (95% confidence interval (CI), 1.41–1.86, p < 0.001), and the aHR was 1.56 (95% CI, 1.36–1.79, p < 0.001). The methotrexate nonusers exhibited an aHR (vs. controls) of 1.61 (95% CI, 1.40–1.85, p < 0.001), but the methotrexate users did not have a significantly higher aHR than the controls. The steroid nonusers had an aHR (vs. controls) of 1.69 (95% CI, 1.46–1.96, p < 0.001), but the aHR of the steroid users was not significantly higher than the control aHR. Patients with RA had a higher risk for RCD compared with the non-RA control cohort. Steroids or methotrexate use significantly reduces the risk of RCD occurrence in patients with RA. Treatment for RCD symptoms and controlling inflammatory process are important to ensure high-quality care for patients with RA.

The role of ultrasound-defined tenosynovitis and synovitis in the prediction of rheumatoid arthritis development

OBJECTIVES

Tenosynovitis (TS) is common in early arthritis. However, the value of US-defined TS in predicting RA development is unclear. We assessed the predictive utility of US-defined TS alongside US-defined synovitis and clinical and serological variables in a prospective cohort of early arthritis patients.

METHODS

One hundred and seven patients with clinically apparent synovitis of one or more joint and symptom duration ⩽3 months underwent baseline clinical, laboratory and US assessment of 19 bilateral joint sites and 16 bilateral tendon compartments. Diagnostic outcome was determined after 18 months, applying the 2010 ACR/EULAR classification criteria for RA. The predictive values of US-defined TS for persistent RA were compared with those of US-defined synovitis, clinical and serological variables.

RESULTS

A total of 4066 US joint sites and 3424 US tendon compartments were included in the analysis. Forty-six patients developed persistent RA, 17 patients developed non-RA persistent disease and 44 patients had resolving disease at follow-up. US-defined TS in at least one tendon compartment at baseline was common in all groups (RA 85%, non-RA persistent disease 71% and resolving 70%). On multi-variate analysis, US-defined digit flexor TS provided independent predictive data over and above the presence of ACPA and US-defined joint synovitis.

CONCLUSION

US-defined digit flexor TS provided independent predictive data for persistent RA development in patients with early arthritis. The predictive utility of this tendon site should be further assessed in a larger cohort; investigators designing imaging-based predictive algorithms for RA development should include this tendon component as a candidate variable.

Sonographic Characteristics of Extensor Tendon Abnormalities and Relationship With Joint Disease Activity in Rheumatoid Arthritis: A Pilot Study

OBJECTIVES

To characterize abnormalities in the dorsal extensor tendons of the hand and determine the importance of these findings in rheumatoid arthritis.

METHODS

A retrospective cross-sectional study was done on 26 patients with rheumatoid arthritis who had sonography of their hands. B-mode and power Doppler joint activity were scored, and the extensor tendons were examined for B-mode changes and power Doppler signals. B-mode changes included anechoic fluid around tendons, hypoechoic tissue around tendons, paratendon tissue and tendon thickening, as well as vascularity around the tendon, for which peritendon power Doppler signals were recorded.

RESULTS

Forty-one hands and 205 joints were reviewed. Anechoic fluid around the tendons and peritendon power Doppler signals were observed in 41% and 39%, respectively; 44% and 28% of patients had B-mode and power Doppler scores in the upper tertile, respectively. For both B-mode and power Doppler scores, 3 categories or tertiles were created, 0 to 0.9, 1 to 1.9, and 2 to 3. We reported the percentage of patients with power Doppler and B-mode scores in this category. The severity of synovitis was associated with anechoic fluid around the tendons and peritendon power Doppler signals according to the Cochran-Mantel-Haenszel test. The common odds ratio was 3.52 (95% confidence interval, 1.45- 8.53) for anechoic fluid around the tendons and severe synovitis. The common odds ratio was 2.52 (95% confidence interval, 1.13-5.63) for peritendon power Doppler signals and severe synovitis.

CONCLUSIONS

Findings at the dorsal extensor tendons were anechoic fluid around tendons, hypoechoic tissue around tendons, peritendon power Doppler signals, and tendon thickening. Patients with anechoic fluid and power Doppler signals were found to have more severe disease activity at the joints based on B-mode and power Doppler scores.

Ultrasound evaluation of adult-acquired flatfoot deformity: Emphasis on the involvement of spring ligament

Adult-acquired flatfoot deformity (AAFD), a condition commonly caused by tibialis posterior tendon (TPT) dysfunction, has recently been recognised to encompass a spectrum of other deformities, including the disruption of the spring ligament complex. This case series reviews eight examples of chronic AAFD, outlines the sonographic assessment of the TPT and spring ligament and depicts various abnormalities of the TPT and spring ligament that are relevant to AAFD. The importance to always include the spring ligament during the assessment of AAFD will be addressed, as misdiagnosis of the involvement of the spring ligament could lead to inappropriate operative management.

The influence of long distance running on sonographic joint and tendon pathology: results from a prospective study with marathon runners

Background

The impact of physical exercise on joints and tendons is still a matter of debate. The aim of this study was to investigate with ultrasound the acute effects of extreme physical exercise on knee and ankle joints and their surrounding structures in trained athletes.

Methods

Participants of the Munich marathon were examined by arthrosonography before and after long distance running. Ultrasound assessment included grey scale and power Doppler examination of the knee and talocrural joints with surrounding tendons. Findings consistent with joint effusion, tendon and/or entheseal pathologies were documented. In addition to the ultrasound evaluation, information on training habits and past or present arthralgia or joint swelling was gathered.

Results

One Hundred Five runners completed both the pre- and post-excercise ultrasound assessments (baseline and follow-up), resulting in the sonographic evaluation of 420 knee and talocrural joints. At baseline, 105 knee (50) and 38 talocrural joints (18.1) showed effusions, compared to 100 knee (47.6) and 33 talocrural joints (15.7 %) at follow-up. The differences were not significant (p > 0.05 each). Effusion size did not correlate with the timepoint of ultrasound assessment and was independent of covariates such as gender, age or running distance. Hypervascularity of the patellar tendon was detected in 21 cases (10.0 %) at follow-up in contrast to one at baseline (p < 0.001). This observation was more frequent in male than in female participants (p < 0.05).

Conclusions

Acute physical stress is significantly associated with hypervascularity of the patellar tendon. No significant changes of synovial effusion were detected in knee and talocrural joints.

How does a cadaver model work for testing ultrasound diagnostic capability for rheumatic-like tendon damage?

To establish whether a cadaver model can serve as an effective surrogate for the detection of tendon damage characteristic of rheumatoid arthritis (RA). In addition, we evaluated intraobserver and interobserver agreement in the grading of RA-like tendon tears shown by US, as well as the concordance between the US findings and the surgically induced lesions in the cadaver model. RA-like tendon damage was surgically induced in the tibialis anterior tendon (TAT) and tibialis posterior tendon (TPT) of ten ankle/foot fresh-frozen cadaveric specimens. Of the 20 tendons examined, six were randomly assigned a surgically induced partial tear; six a complete tear; and eight left undamaged. Three rheumatologists, experts in musculoskeletal US, assessed from 1 to 5 the quality of US imaging of the cadaveric models on a Likert scale. Tendons were then categorized as having either no damage, (0); partial tear, (1); or complete tear (2). All 20 tendons were blindly and independently evaluated twice, over two rounds, by each of the three observers. Overall, technical performance was satisfactory for all items in the two rounds (all values over 2.9 in a Likert scale 1-5). Intraobserver and interobserver agreement for US grading of tendon damage was good (mean κ values 0.62 and 0.71, respectively), with greater reliability found in the TAT than the TPT. Concordance between US findings and experimental tendon lesions was acceptable (70-100 %), again greater for the TAT than for the TPT. A cadaver model with surgically created tendon damage can be useful in evaluating US metric properties of RA tendon lesions.

Structural damage in rheumatoid arthritis: comparison between tendon damage evaluated by ultrasound and radiographic damage

OBJECTIVE

To compare structural damage assessed by conventional radiography and tendon damage assessed by musculoskeletal US (MSUS) at wrist and ankle in RA patients.

METHODS

We evaluated 72 consecutive patients [56 (77.8%) females] with RA. The MSUS evaluation consisted in a B-mode examination of bilateral extensor carpi ulnaris and tibialis posterior tendons. Tendon damage was defined and scored according to OMERACT. A total score for the tendon damage score (TDS) was calculated by summing the grades for each tendon. For the radiographic evaluations we used the van der Heijde score; a total radiographic score (RTS) was calculated by summing a bone erosion score (ERS) and a joint space narrowing score (JSNS).

RESULTS

We evaluated 288 tendons. The mean (s.d.) of TDS was 2.3 (1.8). Fifty-four (75%) patients presented tendon damage of at least one tendon. From all evaluated tendons, 134 (46.5%) had no tendon damage, 146 (50.7%) had grade 1 and 8 (2.8%) had grade 2 tendon damage. The mean (s.d.) for RTS was 91.4 (97), for ERS was 47.3 (61.9) and for JSNS was 44.1 (37.2). We found a significant correlation between disease duration and both TDS and RTS (r = 0.413 and r = 0.560, respectively; P < 0.0001). We found a good significant correlation between TDS and all variables of radiographic structural damage (RTS, r = 0.65; ERS, r = 0.637; JSNS, r = 0.618; P < 0.001).

CONCLUSION

The MSUS assessment of only four tendons can be an additional feasible method to assess structural damage in RA patients.

The OMERACT Ultrasound Working Group 10 Years On: Update at OMERACT 12

Musculoskeletal ultrasound (US) now thrives as an established imaging modality for the investigation and management of chronic inflammatory arthritis. We summarize here results of the Outcome Measures in Rheumatology (OMERACT) US working group (WG) projects of the last 2 years. These results were reported at the OMERACT 12 meeting at the plenary session and discussed during breakout sessions. Topics included standardization of US use in rheumatic disease over the last decade and its contribution to understanding musculoskeletal diseases. This is the first update report of WG activities in validating US as an outcome measure in musculoskeletal inflammatory and degenerative diseases, including pediatric arthritis, since the OMERACT 11 meeting.

[Rheumatic tendon pathologies]

BACKGROUND

Rheumatoid arthritis is found in approximately 2 % of the total population in Europe and the peak incidence of the disease is during the fourth and fifth decades of life. In approximately 15 % the first symptoms of the disease occur at the level of the foot and ankle. If the early stage-dependent therapy with pharmaceuticals fails isolated surgery of the tendons (e.g. tenosynovectomy) and reconstructive surgery including the tendons (e.g. tendon transfer and tendon readaptation) are performed to keep the patient mobile.

OBJECTIVES

The aim of this article is to give an overview of the most commonly used interventions in the reconstruction of tendons in rheumatism patients and the corresponding indications. The conservative therapy options for rheumatic foot and ankle alterations with a special emphasis on tendon pathologies have a well-established importance and are also presented.

METHODS

A selective literature search was carried out for therapeutic options of rheumatic tendon pathologies.

DISCUSSION

If possible attempts should be made to preserve functional qualities using tenosynovectomy, tendon sutures or tendon transfer operations. If joints are already destroyed or dislocated, tendon operations should be carried out only as combined interventions with arthrodesis, endoprostheses or resection arthroplasty. The time window in which these interventions are possible should not be missed. Orthotic devices, bandages or even orthopedic shoes provide external support and splinting but do not represent a causal therapy.

[Ultrasonography in chronic inflammatory rheumatic and connective tissue disorders]

Musculoskeletal ultrasonography is now widely used by almost all rheumatologists thanks to an improvement in the quality of ultrasound unit and probe and to the systematic teaching of this imaging technique to the rheumatology fellows. Applications have broadened from the study of degenerative and mechanical diseases to inflammatory rheumatic diseases. Ultrasound is more sensitive than clinical examination. Power Doppler allows the direct visualisation of inflammation within the tissues. Finally, it is a prognostic tool helping the physician in the management of the disease. This review will focus on the value and applications of ultrasonography in the 2 most frequent rheumatic diseases: rheumatoid arthritis and spondyloarthritis. We will also give some recent data on the usefulness of this imaging technique in the study of musculoskeletal manifestations associated with connective tissue disease.

Responsiveness in Rheumatoid Arthritis. A Report from the OMERACT 11 Ultrasound Workshop

Objective.

To summarize the work performed by the Outcome Measures in Rheumatology (OMERACT) Ultrasound (US) Task Force on the validity of different US measures in rheumatoid arthritis (RA) and juvenile idiopathic arthritis (JIA) presented during the OMERACT 11 Workshop.

Methods.

The Task Force is an international group aiming to iteratively improve the role of US in arthritis clinical trials. Recently a major focus of the group has been the assessment of responsiveness of a person-level US synovitis score in RA: the US Global Synovitis Score (US-GLOSS) combines synovial hypertrophy and power Doppler signal in a composite score detected at joint level. Work has also commenced examining assessment of tenosynovitis in RA and the role of US in JIA.

Results.

The US-GLOSS was tested in a large RA cohort treated with biologic therapy. It showed early signs of improvement in synovitis starting at Day 7 and increasing to Month 6, and demonstrated sensitivity to change of the proposed grading. Subsequent voting questions concerning the application of the US-GLOSS were endorsed by > 80% of OMERACT delegates. A standardized US scoring system for detecting and grading severity of RA tenosynovitis and tendon damage has been developed, and acceptable reliability data were presented from a series of exercises. A preliminary consensus definition of US synovitis in pediatric arthritis has been developed and requires further testing.

Conclusion.

At OMERACT 11, consensus was achieved on the application of the US-GLOSS for evaluating synovitis in RA; and work continues on development of RA tenosynovitis scales as well as in JIA synovitis.

Power Doppler ultrasound phenotyping of expanding versus collapsed popliteal lymph nodes in murine inflammatory arthritis

Rheumatoid arthritis is a chronic inflammatory disease manifested by episodic flares in affected joints that are challenging to predict and treat. Longitudinal contrast enhanced-MRI (CE-MRI) of inflammatory arthritis in tumor necrosis factor-transgenic (TNF-Tg) mice has demonstrated that popliteal lymph nodes (PLN) increase in volume and contrast enhancement during the pre-arthritic “expanding” phase of the disease, and then suddenly “collapse” during knee flare. Given the potential of this biomarker of arthritic flare, we aimed to develop a more cost-effective means of phenotyping PLN using ultrasound (US) imaging. Initially we attempted to recapitulate CE-MRI of PLN with subcutaneous footpad injection of US microbubbles (DEFINITY®). While this approach allowed for phenotyping via quantification of lymphatic sinuses in PLN, which showed a dramatic decrease in collapsed PLN versus expanding or wild-type (WT) PLN, electron microscopy demonstrated that DEFINITY® injection also resulted in destruction of the lymphatic vessels afferent to the PLN. In contrast, Power Doppler (PD) US is innocuous to and efficiently quantifies blood flow within PLN of WT and TNF-Tg mice. PD-US demonstrated that expanding PLN have a significantly higher normalized PD volume (NPDV) versus collapsed PLN (0.553±0.007 vs. 0.008±0.003; p<0.05). Moreover, we define the upper (>0.030) and lower (<0.016) quartile NPDVs in this cohort of mice, which serve as conservative thresholds to phenotype PLN as expanding and collapsed, respectively. Interestingly, of the 12 PLN phenotyped by the two methods, there was disagreement in 4 cases in which they were determined to be expanding by CE-MRI and collapsed by PD-US. Since the adjacent knee had evidence of synovitis in all 4 cases, we concluded that the PD-US phenotyping was correct, and that this approach is currently the safest and most cost-effective in vivo approach to phenotype murine PLN as a biomarker of arthritic flare.

Ultrasound definition of tendon damage in patients with rheumatoid arthritis. Results of a OMERACT consensus-based ultrasound score focussing on the diagnostic reliability

OBJECTIVE

To develop the first ultrasound scoring system of tendon damage in rheumatoid arthritis (RA) and assess its intraobserver and interobserver reliability.

METHODS

We conducted a Delphi study on ultrasound-defined tendon damage and ultrasound scoring system of tendon damage in RA among 35 international rheumatologists with experience in musculoskeletal ultrasound. Twelve patients with RA were included and assessed twice by 12 rheumatologists-sonographers. Ultrasound examination for tendon damage in B mode of five wrist extensor compartments (extensor carpi radialis brevis and longus; extensor pollicis longus; extensor digitorum communis; extensor digiti minimi; extensor carpi ulnaris) and one ankle tendon (tibialis posterior) was performed blindly, independently and bilaterally in each patient. Intraobserver and interobserver reliability were calculated by κ coefficients.

RESULTS

A three-grade semiquantitative scoring system was agreed for scoring tendon damage in B mode. The mean intraobserver reliability for tendon damage scoring was excellent (κ value 0.91). The mean interobserver reliability assessment showed good κ values (κ value 0.75). The most reliable were the extensor digiti minimi, the extensor carpi ulnaris, and the tibialis posterior tendons. An ultrasound reference image atlas of tenosynovitis and tendon damage was also developed.

CONCLUSIONS

Ultrasound is a reproducible tool for evaluating tendon damage in RA. This study strongly supports a new reliable ultrasound scoring system for tendon damage.

Reliability of side-to-side sonographic cross-sectional area measurements of upper extremity nerves in healthy volunteers

OBJECTIVES

In sonographic evaluations of peripheral nerves, the healthy, contralateral side may be used as an internal control for the pathologic one. Therefore, the inherent side-to-side differences must be minimal. The goal of this study was to determine the reliability of side-to-side measurements of upper extremity nerves in healthy volunteers.

METHODS

Forty participants with no upper extremity abnormalities were included. Upper limb nerves were evaluated bilaterally at the usual pathologic sites by 3 musculo-skeletal radiologists in separate sessions. To assess intraobserver and interobserver agreement, sonographic examinations were repeated 2 months after the first evaluations. The median nerve, ulnar nerve, musculocutaneous nerve, and radial nerve were considered. Nonparametric tests were used for statistical analysis.

RESULTS

Minimum detectable differences with relative 95% confidence intervals were reported. Intraobserver and interobserver agreements were good (0.73 < κ < 0.85). When the combined influence of the observer and the repeated measurement was evaluated, the reliability was 80% to 87%.

CONCLUSIONS

In general, the healthy contralateral side can be used as an internal control considering that changes in minimum detectable differences are related to the anatomic site considered.

Reliability of a consensus-based ultrasound score for tenosynovitis in rheumatoid arthritis

OBJECTIVE

To produce consensus-based scoring systems for ultrasound (US) tenosynovitis and to assess the intraobserver and interobserver reliability of these scoring systems in rheumatoid arthritis (RA).

METHODS

We undertook a Delphi process on US-defined tenosynovitis and US scoring system of tenosynovitis in RA among 35 rheumatologists, experts in musculoskeletal US (MSUS), from 16 countries. Then, we assessed the intraobserver and interobserver reliability of US in scoring tenosynovitis on B-mode and with a power Doppler (PD) technique. Ten patients with RA with symptoms in the hands or feet were recruited. Ten rheumatologists expert in MSUS blindly, independently and consecutively scored for tenosynovitis in B-mode and PD mode three wrist extensor compartments, two finger flexor tendons and two ankle tendons of each patient in two rounds in a blinded fashion. Intraobserver reliability was assessed by Cohen's κ. Interobserver reliability was assessed by Light's κ. Weighted κ coefficients with absolute weighting were computed for B-mode and PD signal.

RESULTS

Four-grade semiquantitative scoring systems were agreed upon for scoring tenosynovitis in B-mode and for scoring pathological peritendinous Doppler signal within the synovial sheath. The intraobserver reliability for tenosynovitis scoring on B-mode and PD mode was good (κ value 0.72 for B-mode; κ value 0.78 for PD mode). Interobserver reliability assessment showed good κ values for PD tenosynovitis scoring (first round, 0.64; second round, 0.65) and moderate κ values for B-mode tenosynovitis scoring (first round, 0.47; second round, 0.45).

CONCLUSIONS

US appears to be a reproducible tool for evaluating and monitoring tenosynovitis in RA.