Ultrasonography (US)-guided injection of glucocorticoids into tendon sheaths provided better disease control than intramuscular injection for patients with rheumatoid arthritis and tenosynovitis in a randomized, double-blind, controlled study. US remission of tenosynovitis (defined as greyscale score ≤1 and colour Doppler score = 0) at week 4 was achieved by 64% (16/25) of patients who received intratenosynovial injections, compared with 25% (6/24) who received intramuscular injections (P = 0.001). Remission rates also differed significantly at week 12 (44% versus 8%, P = 0.001).