Objective To evaluate the value of high-frequency color Doppler ultrasound in the examination of pathological changes in the peripheral joints of patients with early rheumatoid arthritis (RA).Methods Peripheral joints of 30 consecutive patients with early rheumatoid arthritis (disease duration ＜1year) and 15 healthy volunteers were assessed with ultrasound searching for joint effusion,synovial hypertrophy,tendon lesion and bone erosions.The joints examined including bilateral elbows,wrists,knees,ankles,metacarpophalangeal joints (MCP),proximal interphalangeal joints (PIP) and metatar-sophalangeal joints (MTP).Data were analyzed with t-test and kappa test.Results Joint effusion and/or synovial hypertrophy were found in 471 joints (41.3％).Four hundred and four (35.4％) joints had joint effusion,359(31.5％) had synovial hypertrophy.Power Doppler signals were found in 128 (35.7％) joints with synovial hypertrophy.Periarticular tendon lesions were found in 90(25％) joints of all wrists,ankles and the 2nd to 5th metacarpophalangeal joints.Bone erosions were detected in 27 (2.4％) joints.The most likely involved joint in all peripheral jints was wrist which had the highest positive rate of effusion,synovial hypertrophy,bone erosion and power Doppler signals in the synovial membrane.Other joints which were easily involved with synovitis were knee,ankle,elbow,MTP,MCP and PIP.The positive rate of synovitis was highest in the MTP of all small joints exception the wrist.Synovitis present most frequently in the 2nd MCP of all MCPs,the 3rd PIP of all PIPs and the 2nd MTP of all MTPs.The kappa coefficient between clinical examination and ultrasound in the detection of peripheral joints synovitis was 0.21,showing very poor agreement.Conclusion High-frequency color Doppler ultrasound exa.mination is an effective method in assessing the pathological changes of peripheral joints of patients with early rheumatoid arthritis.It may improve the early diagnosis of RA and useful in assessing disease activity comprehensively.