To compare the short-term efficacy of conventional blind injection (CBI) versus ultrasound-guided injection (USGI) of corticosteroids (CS) injection in tenosynovitis in patients with chronic arthritis and to investigate if the USGI is a less painful procedure and if there are differences in the changes of US findings during the post injection follow-up.

Patients presenting tenosynovitis requiring CS injection were involved. After clinical and US evaluation, patients were randomized to receive CBI or USGI. Efficacy of procedure was assessed by the improvement in both Health Assessment Questionnaire (HAQ) and pain visual analogue scale (VAS), including procedure-VAS global-VAS and local-VAS, after 1 and 4 weeks post-procedure. Power Doppler (PD) and greyscale (GS) US findings were also object of the follow-up. CBI or USGI under an aseptic technique were performed according the local guidelines using 20mg of methylprednisolone acetate.

A total of 114 patients were randomized to receive CBI (54 patients) or USGI (60 patients) procedure. No significant difference was observed in terms of gender, age and pain duration among CBI and USGI groups at baseline. USGI proved to be significantly less painful than CBI (P=0.0001). AUC analysis showed that during the follow up visits, the USGI procedure had significantly better response in HAQ, local-VAS and global-VAS (P=0.0001, P=0.012 and P=0.0001 respectively) compared to CBI. During the follow up period, a significant greater reduction in the PD scores was found in the USGI group compared to the CBI group (P=0.0002), whereas no statistical differences were found in the GS findings between the groups (P=0.5627).

Our study demonstrates superiority of USGI over CBI for CS injections in painful tenosynovitis, having better short-term outcomes measured by functional, clinical and US scores. These data support the use of USGI for tenosynovits in typical inpatient and/or outpatient in rheumatological practices.