OBJECTIVETo investigate whether there is a difference in the efficacy of intra-articular injection of tumor necrosis factor (TNF) inhibitor and triamcinolone acetonide (HA) in rheumatoid arthritis (RA) patients with recurrent synovitis after the first intra-articular injection of HA.METHODSRA patients who relapsed 12 weeks after the first HA treatment were enrolled in this study. After joint cavity extraction, recombinant human TNF receptor-antibody fusion protein (TNFR:FC) (25 mg or 12.5 mg) or HA (1 ml or 0.5 ml) was injected then. The changes in the visual analog scale (VAS), joint swelling index, and joint tenderness index before and 12 weeks after reinjection were compared and analyzed. The changes in synovial thickness, synovial blood flow, and fluid dark zone depth before and after reinjection were observed by ultrasound.RESULTSForty-two RA patients were enrolled, including 11 males and 31 females, with an average age of 46.79 ± 12.61 years and an average disease duration of 7.76 ± 5.44 years. After 12 weeks of intra-articular injection of HA or TNFR:FC, the VAS scores were significantly lower than those before treatment (P < 0.01). After 12 weeks of injection, the scores of the joint swelling index and tenderness index in both groups were significantly decreased compared with those before treatment. There was no significant difference in synovial thickness under ultrasound in the HA group before and after injection, while the synovial thickness in the TNFR:FC group was significantly improved after 12 weeks (P < 0.01). After 12 weeks of injection, the grade of synovial blood flow signal in both groups decreased significantly compared with that before treatment, especially in the TNFR:FC group. After 12 weeks of injection, the depth of the liquid dark area under ultrasound decreased significantly in the HA group and TNFR:FC group compared with that before treatment (P < 0.01).CONCLUSIONIntra-articular injection of a TNF inhibitor is an effective method for the treatment of recurrent synovitis after conventional hormone therapy. Compared with HA treatment, it can reduce synovial thickness. Key Points • Intra-articular injection of a TNF inhibitor is an effective method for the treatment of recurrent synovitis after conventional hormone therapy. • Compared with HA treatment, intra-articular injection of biological agents combined with glucocorticoids can not only relieve joint pain but also significantly inhibit joint swelling. • Compared with HA treatment, intra-articular injection of biological agents combined with glucocorticoids cannot only improve synovial inflammation but also inhibit synovial proliferation. • For the treatment of refractory RA synovitis, biological agents combined with glucocorticoid injection are an effective and safe option.