AB1219 Contribution of mri to cervical involvement in rheumatoid arthritis: prospective study of 30 cases

Background Cervical spine involvement is common during RA and is characterised by its potential severity. Objectives To determine the prevalence of cervical involvement in RA, to clarify the contribution of MRI to diagnosis and to identify predictive factors for cervical rheumatoid involvement. Methods Our study included 30 RA patients with a duration of more than 2 years. Results 16 patients (53%) were assessed on the two imaging methods (standard radiographs in 37% and MRI in 53%), of which 2 cases (7%) were asymptomatic. This cervical involvement was dominated by the C1-C2 pannus objectivated in 50% of cases and AAS. Of the AAS, aAAS was the most frequent with a prevalence of 23%, followed by the pAAS found in 10% of the cases, the vAAS present in 7% of the cases then the lAAS and the rAAS objectivated in 3% each. The ASS was found in 3 cases(10%), odontoid erosion in 11 cases (37%), C1-C2 arthritis in 5 cases (16%) and inflammatory spondylodiscitis in 6 cases (20%). MRI resulted in a better study of the C1-C2 pannus and odontoid erosions as well as the evaluation of the impact of rheumatoid lesions on the neural axis: a medullary imprint was noted in 4 cases (13%). Several factors were associated with cervical rheumatoid involvement: the presence of cervicobrachial neuralgia or bulbomedullary signs, duration of PR ≥5 years, HAQ score ≥1.1 and positive RF. The search for factors associated with AAS has revealed the duration of the disease, DAS 28≥3.2 and the presence of a biological inflammatory syndrome. Conclusions Cervical involvement accompanies the active and destructive forms of RA. It can be asymptomatic, it is the interest to seek it in a systematic way in RA. The standard radiography with dynamic views is to be realised first-line. The MRI must be indicated in order to make an early diagnosis, to carry out an accurate lesional assessment and to guide the therapeutic decision. Disclosure of Interest None declared