Ultrasound of the wrist in low disease rheumatoid arthritis patients: Intercarpal joint is more sensitive than radio-carpal and distal radio-ulnar joint.

OBJECTIVES

Musculoskeletal ultrasound (MSUS) assessment of disease activity is a valuable tool for guiding therapeutic decisions within a treat-to-target strategy. This study aimed to assess synovitis activity in the wrist joint at different levels using ultrasonography (US) in patients with rheumatoid arthritis (RA).

METHODS

Gray scale synovial hypertrophy (SH) and power Doppler (PD) ultrasound were performed on the dorsal radio-scaphoid, inter-carpal, and radio-ulnar joints of the dominant wrist. A one-way ANOVA with multiple comparisons was conducted for each joint.

RESULTS

A total of 38 patients with RA and wrist joint involvement underwent a standardized PD examination assessing three positions in the wrist. The mean synovial hypertrophy (SH) was 1.08 ± 0.487 at the radio-carpal joints, 1.08 ± 0.487 at the inter-carpal joints, and 0.45 ± 0.602 at the radio-ulnar joints, with significantly higher values at the radio-carpal and inter-carpal joints compared to the radio-ulnar joints. The mean power Doppler (PD) was 0.08 ± 0.273 at the radio-carpal joints, 0.79 ± 0.577 at the inter-carpal joints, and 0.16 ± 0.437 at the radio-ulnar joints, with significantly higher values at the inter-carpal joints. Overall, the inter-carpal joint demonstrated greater sensitivity than the other joints.

CONCLUSIONS

Ultrasound assessment of wrist joints should include intercarpal joints, as they frequently show increased power Doppler activity, indicating higher inflammatory activity. Key Points • The intercarpal joint is the most important component of the wrist for detecting ultrasound activity in clinical practice, particularly in patients with low disease activity in RA patients. • Musculoskeletal ultrasound (MSUS) assessment of disease activity may serve as a valuable tool for guiding therapeutic decisions within a treat-to-target strategy. Further studies are needed to optimize ultrasound evaluation and validate its measurements for clinical use.