Rheumatoid Arthritis (RA) is the most frequent inflammatory rheumatic disease. At the beginning of the disease, where after today‘s knowledge the therapeutic possibilities are largest, the diagnostic methods do not permit a differentiated estimation of the prognosis. Conventional x-rays are mostly normal and serum markers unspecific. So far – in contrast to other diseases – only few information has been drawn from the pathomorphologic substrate “synovium” itself to assess the prognosis. Reasons therefore are found in difficulties in obtaining synovial tissue without surgical intervention, particularly in patients with early arthritis.

By minimalizing the diagnostic instruments and improvement of the technique, nowadays synovial tissue sampling in RA has become minimal invasive and even possible from smallest joints, such as finger joints. Hereby, synovial analysis is open for detecting pathways of inflammation and joint destruction, which might support the advancement of new therapeutic strategies, followed by a better prognosis and outcome of RA.