Title : Shoulder pain in Rheumatoid Arthritis (RA): Ultrasound findings and clinical correlations
Abstract:
Introduction: Shoulder pain is a common yet underrecognized manifestation of Rheumatoid Arthritis (RA). The purpose of this study was to evaluate the prevalence and identify structural abnormalities of shoulder pain in RA patients using High-Resolution musculoskeletal Ultra Sound (HRUS), and to assess clinical correlates including functional disability.
Materials and Methods: This cross-sectional study was conducted in the Department of Physical Medicine and Rehabilitation, Indira Gandhi Institute of Medical Sciences, Patna, over six months. A total of 208 consecutive RA patients fulfilling the 2010 ACR/EULAR criteria were included. Patients with referred pain or psychiatric illness were excluded. Clinical assessment and HRUS of the shoulder were performed by a trained physiatrist, following ESSR 2016 guidelines. Functional disability was measured using the Shoulder Pain and Disability Index (SPADI). Demographic, serological, and clinical data were analyzed using ANOVA, Kruskal-Wallis, and Fisher’s exact tests.
Results: Of 208 RA patients, 105 (50.48%) reported shoulder pain. HRUS revealed subacromial-subdeltoid bursitis in 47.6%, subcoracoid bursitis in 33.3%, synovitis in 15.2%, and effusions or arthritis in 12–14%. Notably, 34.3% of patients had pain without HRUS-detectable abnormalities. Higher pain and SPADI scores were observed in patients with structural abnormalities such as tears and effusions. A significant association was observed between shoulder pain and seropositivity, with 93.3% of symptomatic patients being seropositive (p<0.0001).
Discussion: The findings demonstrate that shoulder pain in RA is prevalent and most often associated with bursitis and synovitis. However, the presence of pain without HRUS abnormalities suggests contributions from early inflammation, neuropathic mechanisms, or systemic disease. The strong correlation with seropositivity reinforces the role of autoantibodies in disease severity and joint involvement.
Conclusion: Shoulder pain affects nearly half of RA patients, is frequently linked to bursitis and synovitis, and strongly associated with seropositivity, underscoring the role of HRUS in early detection and management.
