COSTOVERTEBRAL, COSTOTRANSVERSE, STERNOCLAVICULAR AND MANUBRIOSTERNAL JOINT INVOLVEMENT IN SPONDYLOARTHRITIS: PRELIMINARY RESULTS OF SINGLE CENTRE EXPERIENCE

BackgroundCostovertebral (CV), costotransverse (CTr), sternoclavicular (SC) and manubriosternal (MS) joint involvements may be in spondyloarthritis (SpA). However, the radiological and clinical characteristics of these involvements need further assessment.ObjectivesIn this study, we aimed to determine the characteristics of CV, CTr, SC, and MS joint involvements in SpA patients.MethodsSpA patients (searched from the hospital data-processing system according to ICD-10 system to determine the patients having M07 (enteropathic arthropathies), M45 (ankylosing spondylitis (AS)), M46 (other inflammatory spondylopathies) and/or M48 (other spondylopathies) codes) who have been requested a chest computed tomography (CT) for any reason between January 2010 and December 2020 included in this retrospective cross-sectional analysis. Chest CT reports were reviewed, and any CV, CTr, SC or MS joint involvement attributed to SpA accepted as positive CT for SpA involvement. Demographic/clinic data including smoking status, disease characteristics (duration, drug history, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), Bath Ankylosing Spondylitis Metrology Index (BASMI) and other related parameters) at the time of CT scan were collected and analyzed.ResultsAfter the confirmation of the diagnoses among 1700 patients, total of 339 SpA patients were included in the study. 244 were diagnosed with ankylosing spondylitis (AS), 66 with psoriatic arthritis (PsA), 14 with enteropathic arthritis, 13 with peripheral SpA, and 2 with non-radiographic axial SpA. According to CT reports, the number of patients with inflammatory changes in any of the CV, CTr, SC or MS joints on thoracic CT were 44. Of these patients, 42 were diagnosed with AS (95,5%), 1 with PsA (2,3%), and 1 (2,3%) with peripheral SpA. 39 CV, 9 SC, 5 MS joints, and 3 CTr joints were affected. Joint involvements (17%) were higher in patients with AS than in other patient groups (p<0.001). In the chest CT positive group, Schober’s test, and chest expansion were significantly lower than chest CT negative group. Smoking history, C-reactive protein (CRP) value at diagnosis and at CT evaluation, and disease duration were associated with joint involvement. Demographic and clinical characteristics of patients with and without chest CT involvement were shown in Table 1.Table 1.Demographic and clinical characteristics of patients with and without involvement on chest CTData are presented as median (25-75 percentile) or number (%)CT; computerized tomography, BMI; body mass index, ESR; erythrocyte sedimentation rate, CRP; C-reactive protein, BASDAI; Bath Ankylosing Spondylitis. Disease Activity Index, BASMI; Bath Ankylosing Spondylitis Metrology Index, BASFI; Bath Ankylosing Spondylitis Functional IndexConclusionIn this study, we have found that CV, CTr, SC, and MS joint involvement on thorax CT were more common in men and smokers and were associated with disease duration and appears to affect chest expansion and Schober’s tests. In previous studies, CV and CTr joint involvement in AS patients with chest pain were 80-82% and 60%, respectively [1,2]. Our study showed that 17% of AS patients had involvement regardless of pain symptoms. As this is the preliminary data and the CTs will be re-evaluated by our radiologist, we will be capable to report more unbiased results.References[1]Cerrahoglu L, Unlu Z, Can M, et al. (2002) Lumbar stiffness but not thoracic radiographic changes relate to alteration of lung function tests in ankylosing spondylitis. Clin Rheumatol. 21(4):275-279.[2]Pascual E, Castellano JA, López E. (1992) Costovertebral joint changes in ankylosing spondylitis with thoracic pain. Br J Rheumatol. 31(6):413-415.Disclosure of InterestsNone declared