The predominant symptom in RA is synovitis, while tendinitis and tenosynovitis are relatively more prominent in SLE.

Early inflammatory and structural changes in joints in RA and SLE can be detected by MRI and MSUS.

Clinically relevant synovitis and tenosynovitis are underestimated by clinical examination and disease activity instruments in SLE.

Joint manifestations of disease can differ due to the presence or absence of autoantibodies in RA and by joint disease phenotype in SLE.

Feet are also an important site of joint manifestations in both diseases.