Is articular pain in rheumatoid arthritis correlated with ultrasound power Doppler findings?

Objective: The study is addressed to determine if there is a correlation between intra-articular power Doppler (PD) and pain symptoms in patients with rheumatoid arthritis (RA).

Methods: A cross-sectional study of patients with established RA was rolled out. Seventy-two patients with chronic swelling at metacarpophalangeal (MCP) joints were consecutively enrolled in the study and divided into two groups (painful and painless). In the painful group, the inclusion criteria were pain in the visual analog scale (VAS), from 0 to 10 cm, of at least 4 cm and 0 in the painless group. All two to five MCP joints, bilaterally, were scanned by ultrasound (US) searching for intra-articular PD presence. Any value of p < 0.05 was considered significant.

Results: Patients in the painful group had longer morning stiffness, worse 28-joint disease activity score (DAS 28), and health assessment questionnaire (HAQ) indexes. There were no association between pain and gray scale (GS) synovitis, odds ratio (OR) = 0.9 (0.6-1.2), p = 0.485; and pain and intra-articular PD, OR = 0.8 (0.6-1.2), p = 0.244.

Conclusion: Intra-articular PD was not correlated with pain symptom in this study.