Musculoskeletal Ultrasound

Ultrasound in Rheumatoid Arthritis: Assessment of Synovitis Using the EULAR-OMERACT Scale (0–3) and Power Doppler

Name: Ultrasound in Rheumatoid Arthritis: Assessment of Synovitis Using the EULAR-OMERACT Scale (0–3) and Power Doppler
Creator: Knyazev Konstantin Andreevich

Author: Knyazev Konstantin Andreevich, Leading instructor of the MEDTRAIN Training Center, physician in ultrasound and functional diagnostics · Reviewed by a doctor: Blagodir Boris Vladislavovich · Updated: 19 July 2026

Briefly. Ultrasound assessment of synovitis in rheumatoid arthritis combines grayscale mode analysis and power Doppler using the standardized consensus EULAR-OMERACT scale. The physician's task is to identify hypoechoic synovial proliferation, differentiate it from effusion, and record the degree of hyperemia, which is important for assessing disease activity and prognosis [clarify].

Principles of Synovitis Assessment

When scanning the joints of the hand and wrist, longitudinal and transverse planes from anatomical landmarks are used. Joint distension, hypo-/hyperechoic synovial proliferation, and joint effusion deeper than the echogenic capsule are assessed (Griffith, 2025). To differentiate fluid from synovitis, color Doppler and, to a lesser extent, probe compression are used.

Grayscale Mode and EULAR-OMERACT Grades

The standardized consensus system for synovitis assessment was developed by the EULAR-OMERACT ultrasound working group; its reliability and applicability to multiple joints have been confirmed (Terslev L, Naredo E, Aegerter P et al. RMD Open 2017; 3: e000427). The relevance of grade 1 grayscale findings in wrists and small joints for assessing subclinical synovitis in RA is discussed in the literature (Witt M et al., 2013).

The significance of the assessment zone is noted: palmar compared to dorsal assessment of synovitis in RA (Vlad V et al., BMC Musculoskelet Disord 2011).

Power Doppler

To assess hyperemia, it is necessary to optimize device settings, use minimal probe pressure, and record the degree as mild, moderate, or severe (Griffith, 2025). The settings of power and color Doppler directly affect the scoring of disease activity in patients with RA (Torp-Pedersen S et al., Arthritis Rheumatol 2015;67(2):386–395).

Power Doppler is used for quantitative assessment of hand synovitis in RA, including monitoring response to anti-TNF-α therapy (Ribbens C et al., Radiology 2003;229(2):562–569). In very early inflammatory arthritis, adding power Doppler to standard assessment methods increases diagnostic value (Freeston JE et al., Ann Rheum Dis 2010), and erosions and power Doppler signal have prognostic significance regarding radiographic damage (Funck-Brentano T et al., 2013).

Tenosynovitis

In addition to synovitis, tenosynovitis is assessed; a semi-quantitative OMERACT system, sensitive to changes, has been validated for it (Ammitzboll-Danielsen M et al., Rheumatology 2016). A significant feature is the peritendinous hypoechoic rim on power Doppler (Breidahl WH et al., J Ultrasound Med 1998).

Frequently asked questions

What scale is used for standardized synovitis assessment?

The EULAR-OMERACT consensus system by the ultrasound working group; its reliability and applicability to multiple joints have been confirmed (Terslev L et al., RMD Open 2017).

How to differentiate effusion from synovitis?

Color Doppler and, to a lesser extent, probe compression help; synovial proliferation appears as hypo-/hyperechoic tissue deeper than the echogenic capsule (Griffith, 2025).

How to properly assess hyperemia with power Doppler?

Optimize device settings, use minimal probe pressure, and record the degree as mild, moderate, or severe. Doppler settings directly affect the scoring (Torp-Pedersen S et al., 2015).

Is there significance to grade 1 grayscale findings?

The relevance of grade 1 grayscale findings in wrists and small joints for assessing subclinical synovitis in RA is considered in the literature (Witt M et al., 2013).

Does power Doppler have prognostic value?

Yes: erosions and power Doppler signal have prognostic significance regarding radiographic damage in early arthritis (Funck-Brentano T et al., 2013).

The material is intended for specialists and does not replace clinical judgment. Threshold values are periodically reviewed — refer to the current edition of the applicable consensus.

Sources: Fundamentals of Musculoskeletal Ultrasound, 4th ed. (Jacobson, 2026); Diagnostic Ultrasound: Musculoskeletal, 3rd ed. (Griffith, 2025); EFSUMB Guidelines Part II (Naredo et al., 2022); EFSUMB Guidelines Part I (Fodor et al., 2022); Terslev L et al., RMD Open 2017; Torp-Pedersen S et al., Arthritis Rheumatol 2015; Ribbens C et al., Radiology 2003; Vlad V et al., BMC Musculoskelet Disord 2011; Witt M et al., 2013; Freeston JE et al., Ann Rheum Dis 2010; Ammitzboll-Danielsen M et al., Rheumatology 2016; Breidahl WH et al., J Ultrasound Med 1998.

View specialty courses: Musculoskeletal Ultrasound →