AB0917 Clinical, biological and radiological particularities of destructive hip arthritis in ankylosing spondylitis

Background The hip involvement in patients with ankylosing spondylitis (AS) has been recognized as a common and disabling problem. Many radiological pattern of hip arthritis were recognized and seems to have different clinical profile. Objectives to compare the destructive hip arthritis to other radiological pattern in patients with AS. Methods One hundred patients with AS, diagnosed according to the modified New York criteria for AS, and with hip involvement were recruited. Clinical, biological and radiological examinations for AS and for the hip involvement were performed and disease-specific instruments (BASFI, BASDAI, BASG-s, BASMI, BASRI, mSASSS) were assessed. Chi2 test was used to compare qualitative variables and ANOVA for quantitative variables. Results Eighty-one males and 19 females with AS were included in this study. Their mean age was 36.3 years ± 12.3. The mean disease duration was 12.3 years ± 0.9. Sixty-two patients were HLA-B27 positive. The hip involvement was bilateral in 76 cases (176 hips), inaugural in 46 cases and for the others, the mean disease duration at hip arthritis onset was 5.6 years. The destructive hip arthritis was found in 65% of cases and was associated among hip arthritis parameters to Lequesne index, reduced maximum distance walked, lameness, limitations in hip rotation and total hip replacement requirement. Among AS parameters destructive arthritis was associated to high score of BASRI, high level of ESR and presence of B27 antigen. Conclusions The destructive hip arthritis seems to be the most frequent radiological pattern and associated to the presence of HLA B27 antigen and to a worse prognosis. Disclosure of Interest None Declared