Intraarticular glucocorticoid injections are common in rheumatoid arthritis (RA) treatment. This study was undertaken to investigate whether ultrasound in combination with clinical examination is better than clinical examination alone at identifying joints that will benefit from intraarticular injections, and to compare the efficacy of ultrasound-guided versus palpation-guided procedures.
In the treat-to-target Aiming for Remission in Rheumatoid Arthritis: a Randomised Trial Examining the Benefit of Ultrasonography in a Clinical Tight Control Regimen (ARCTIC), patients with early RA were randomized 1:1 to follow-up with or without ultrasound. In addition to disease-modifying antirheumatic drugs, intraarticular glucocorticoids were used to treat inflamed joints. The distribution of injections was assessed in both study groups. The relationship of clinical and ultrasound findings at the time of injection with treatment efficacy was examined, with non-swollen joint at the next visit as the outcome measure. Treatment success was compared across study groups to evaluate ultrasound-guided versus palpation-guided procedures.
More injections were administered in the ultrasound group than in the conventional strategy group (n = 770 versus 548), especially in intercarpal joints (n = 58 versus 5) and metatarsophalangeal joints (n = 200 versus 104). Injecting clinically swollen joints without power Doppler (PD) activity on ultrasound was not efficacious compared to not injecting (odds ratio [OR] 1.3; P = 0.59). Efficacy was best in swollen joints (OR 9.0; P = 0.001) and non-swollen joints (OR 8.4; P = 0.016) with moderate PD activity. Treatment success was similar for the ultrasound-guided and palpation-guided procedures.
Our findings indicate that the efficacy of intraarticular glucocorticoid injections varies according to ultrasound findings at the time of injection, supporting the use of ultrasound as a tool to select joints that will benefit from intraarticular injections. However, ultrasound needle guidance was not superior to palpation guidance.