The purpose of this study is to:

1. To investigate the wrist joint synovial blood flow intensity and model by quantitative three-dimensional (3D) power Doppler ultrasonography (PDUS) in patients with rheumatoid arthritis before and after initiation of a new medicine and compare these data with routinely used clinical data and laboratory findings, such as pain score, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP)
2. To investigate the intra-observer and inter-observer agreement of quantitative 3D PDUS assessment of the vascularity in wrist joints and knee joints using automatic volume scan.

Inclusion Criteria:

• Patients who fulfill the 1987 ARA criteria for RA
• Patients with at least one painful swollen wrist or knee joint observed by a rheumatologist
• Patients who will receive a new medicine, including oral corticosteroid, intravenous methylprednisolone pulse therapy, intraarticular injection with steroid or methotrexate, DMARDs, or biologic agent

Exclusion Criteria:

• Patients with active infection
• Patients with concurrent malignant disease
• Patients with a history of traumatic, septic, or cystal arthritis, previous joint surgery, or arthroscopic synovectomy of any wrist or kneejoint within the past 12 months before the study
• Patients who have severe wrist or knee joint deformity that makes the US assessment protocol unable to complete

A total of 30 patients with RA who visit outpatient clinic of Rheumatology at Taichung Veterans General Hospital (TCVGH) will be enrolled consecutively at if they met the study inclusion criteria