Sample size: 60 cases. Study content: Patients who meet inclusive criteria will be randomly divided into tocilizumab group and compound betamethasone group. In the baseline period, the investigators will collect patients' general information, disease information, disease activity score, laboratory results and images of articular ultrasound. After 4 weeks of injection, patients will be asked to come back, and their disease information, disease activity score, laboratory results as well as images of articular ultrasound will be collected. Finally, these data will be sorted and analyzed.