FACET JOINTS INVOLVEMENT IN RHEUMATOID ARTHRITIS: A CROSS-SECTIONAL STUDY

Background Even it is accepted among rheumatologists that rheumatoid arthritis (RA) does not involve the facet joints (FJs) of the spine, the issue is still under debate. Studies that described a prevalence of the FJs in rheumatoid arthritis patients are scarce.Objectives To compare the prevalence of FJs changes between patients with RA and age and sex-matched peers.Methods We compared computed tomography (CT) scans of 34 patients with RA, who suffered from low back pain, and 70 age and sex-matched controls-people without RA, with low back pain.The changes in FJs were evaluated according to the score proposed by Kalichman et al: joint space narrowing, marginal osteophytes, articular process hypertrophy, subchondral sclerosis, inter-joint vacuum phenomenon, and subchondral cysts. The characteristic joint changes of RA were also evaluated.Disease activity characteristics, duration of RA, age, and gender were taken from patients‘ clinical charts.Results Prevalence of facet joints changes in patients with RA and group of age and sex-matched controls were not significantly different at any spinal level or in total L5-S1 score. Marginal erosions, that are characteristic feature of joint change in RA, were not found in any subject with RA in our sample. In subjects with RA, individuals with affected FJs and without affected FJs have no difference in any disease parameters and markers (Tables 1 and 2).Conclusion In our samples of CT scans we did not find a difference in facet joints changes between the subject with RA and control group. The occurrence of FJs changes among subjects with RA had no correlation with disease duration and activity. According to the findings, we may assume, that facet joints of the lumbar spine are not involved in the inflammatory process of RA, and patients‘ low back pain is not due to inflammation in this region of the spine.View this table:Abstract AB1175 Table 1 Prevalence of FJ degenerative changes in patients with RA and age and sex-matched controls.View this table:Abstract AB1175 Table 2 Association between changes in FJs and disease markers in RA patients (results if one-way ANOVA).CRPtextendash C-reactive protein; ESR textendash Erythrocyte sedimentation rate; DAS-Disease Activity Score; CDAI textendash Clinical Disease Activity Index; SDAI textendash Simple Disease Activity Index.References [1] Kalichman L, Li L, Kim DH, Guermazi A, et al. 2008. Facet Joint Osteoarthritis and Low Back Pain in the Community-Based Population. Spine 33:2560-2565.[2] van der Heijde D, Dankert T, Nieman F, et al. 1999. Reliability and sensitivity to change of a simplification of the Sharp/van der Heijde radiological assessment in rheumatoid arthritis. Rheumatology (Oxford) 38:941-947.Disclosure of Interests Tatiana Reitblat Consultant for: Abbvie, Eli Lilly, Lina Linov: None declared, Fadi Badeer: None declared, Azaria Simonovich: None declared, Leonid Kalichman: None declared