Background/Purpose:                                                              The aim of this study was to compare the efficacy of intramuscular versus ultrasound (US)-guided peritendinous glucocorticoid injection in providing disease control after 2, 4 and 12 weeks in rheumatoid arthritis(RA) patients with tenosynovitis.

Methods: Fifty RA patients with tenosynovitis were randomised into two double-blind groups: A. “intramuscular group”, receiving intramuscular injection of betamethasone and US-guided peritendinous isotonic saline injection and B. “peritendinous group” receiving saline intramuscularly and US-guided peritendinous betamethasone injection. All patients were in stable disease-modifying anti-rheumatic drug treatment prior to and during the study. Patients were excluded, and considered non-responders, if any treatments were altered during the follow-up period. “US tenosynovitis remission”, defined as US tenosynovitis grey-scale score ≤1 and colour Doppler score=0, was assessed at week 4 (primary outcome), and weeks 2 and 12, using non-responder imputation for missing data.  The tenosynovitis was assessed at baseline, 2,  4 and 12 weeks using the semi-quantitative scoring system for GS (0-3) and CD(0-3) as proposed by the OMERACT US group, clinical assessment and a patient reported pain tenosynovitis visual analogue scale (VAS tenosynovitis) from 0-100

Results: US tenosynovitis remission at week 4 was achieved in 25% (6/24) [95% confidence limits: 8%; 42%] in the “intramuscular group”, versus 64% (16/25) [45%; 83%] in the “peritendinous group” (Fisher exact test; p<0.01). Corresponding values for the “intramuscular group” versus the “peritendinous group” at 2 and 12 weeks were 21% [5%; 37%] versus 48% [28%; 68%] (p=0.07) and 8% (0%; 19%) versus 44% (24%; 63%) (p<0.01). Most US and clinical/patient-reported scores improved more in the “peritendinous group” at all follow up visits (see table 1).

Conclusion: In this randomised double-blind clinical trial, RA patients with tenosynovitis responded significantly better to US guided peritendinous glucocorticoid injection than to intramuscular glucocorticoid injection, both at 4 and 12 weeks follow up.