Background. Rheumatoid arthritis (RA), met in the literature also as chronic evolving polyarthritis, is a chronic inflammatory disease, which typically involves the small and medium joints, with a symmetric distribution. Clinical studies shown that a proportion of patients with RA, without measurable rheumatoid factors are a distinct entity from those patients with seropositive RA. Around one third of patients with RA are seronegative for those two serological markers, the rheumatoid factors (RF) and anti-citrullinated peptide antibodies (Anti-CCP). Hands are the most frequently affected in both seropositive and seronegative RA and the first joints involved in the inflammatory process are the metacarpo-phalangeal joints, IFP joints and the radiocarpian joint. The big joints become later symptomatic, after the small joints are affected. Materials and methods: 66 patients files and the personal records of the patients consecutively admitted in the Rheumatology Department of the Clinical Emergency County Hospital Constanta. Patients from county Constanta were included in the study, with diagnosis of rheumatoid arthritis (diagnosis confirmed at least 2 years ago), including both forms (seropositive and seronegative) of the disease. The complete clinical exam was done for the patients included in the study, following the identification of the active joint disease. The mechanical status of the joint was observed by a single evaluator for each of those 66 patients with RA, with special focus on the presence of the deformities / ankyloses of the hands joints. Therefore, there were evaluated: the mobility (the number of the joints with limited movements), deformities, ankyloses (the number of the joints without mobility). The joint mobility was assessed by counting the hand joints with limited movements and the worsening of the prehension function. The presence of the following hand deformities was followed: fingers in “swan neck”, “fusiform fingers”, the thumb “in Z”, and the aspect of “hand in the shape of a camel back”. For evaluating the painful or swollen joints we used: the 28 joint index, the overall evaluation of the disease activity - by the patient (Patient Global Assessment-PGA) and by the doctor (Medical Doctor Global Assessment- MDGA), the score of disease activity DAS 28 (DAS28 - Disease Activity Score 28), the index of the clinical activity of the disease (Clinical Disease Activity Index- CDAI), as well as the simplified index of activity of the disease (Simplified Disease Activity Index-SDAI). It was determined for each patient the plasma RF and anticitrullinated peptide antibodies. Results and discussion. As expected, there is a bigger frequency of female patients in both forms of the disease (seropositive and seronegative) and regarding males the recurrence is approximate equal between those two groups. By comparing the frequency of the joint deformities at hand level between the 2 groups of patients included in the study (seropositive PR and seronegative PR), we saw a superiority of these (with all their forms) in the patients with seropositive polyarthritis. Conclusions. The clinical study done in this work is completing the data offered by the studies of some dedicated authors, who analysed the characteristic elements of rheumatoid arthritis depending on seropositivity. Our results confirm the idea that seronegative rheumatoid arthritis has a more gentle clinical evolution and is a less destructive form of disease.