Scientific Abstracts 1537 There was no association between the different sacroiliac maneuvers on physical examination and the number of children: distraction test (p=0. 145), compression test (p=0.088), Gaenslen test (p=0.475), and Mennel test (p=0.088). BME was more frequent among multiparous women (33% vs 29%) without reaching a sta- tistically signifcant difference (p=0.635). There was no association between the number of children and Hyper T1 (p=0.608), T1 gadolinium (p=0.55) as well as sclerosis (p=0.55). Similarly, there was no association between the presence of Doppler signal on ultrasound and multiparity (p=0.5). Conclusion: Our study showed that MRI-SIJ fndings were similar in nr-axSpA women regardless of the number of children, mainly BME. More trials are needed to evaluate the discriminatory capacity of MRI abnormalities and to palliate to the lack of specifcities of the ASAS MRI criteria. REFERENCES: [1] Germann C, Kroismayr D, Brunner F, Pfrrmann CWA, Sutter R, Zubler V. Infuence of pregnancy/childbirth on long-term bone marrow edema and subchondral sclerosis of sacroiliac joints. Skeletal Radiol. 2021;50(8):1617-1628. Disclosure of Interests: None declared DOI: 10.1136/annrheumdis-2022-eular.3096 AB0820 REMISSION CRITERIA IN NON-RADIOGRAPHIC AXIAL SPONDYLOARTHRITIS: DON’T MISS SUBCLINICAL INFLAMMATION D. Ben Nessib 1 , M. Yasmine 1 , H. Ferjani 1 , W. Triki 1 , K. Maatallah 1 , D. Kaffel 1 , W. Hamdi 1 . 1 Kassab Institute of orthopedics, Rheumatology, Tunis, Tunisia Background: With the advent of the treat-to-target strategy (T2T), clinical remission has become the main objective to achieve in patients with rheumatic diseases. Contrary to rheumatoid arthritis, the T2T strategy is less codifed in axial spondyloarthritis, even more in non-radiographic SpA (nr-axSpA) [1]. More importantly, T2T based on imaging remission and guidance for tapering medica- tion has not been extensively studied. Objectives: The objective of this study was to investigate the prevalence of bone marrow edema in the sacroiliac joint of nr-axSpA patients in remission. Methods: We undertook a cross-sectional study including nr-axSpA patients according to the ASAS criteria, treated with NSAIDs. Socio demographic data as well disease characteristics were recorded. Disease activity parameters were also collected including the duration of morning stiffness, the number night awakening, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). MRI-SIJ was performed for all the patients. All the images were screened for bone marrow edema with the corresponding sequence (short tau inversion). To defne remis- sion, we used in addition to BASDAI<4, more stringent criteria: BASDAI<4 and CRP<6 mg/l and ESR<20 mm/h and EGM<4 [2]. The level of signifcance was fxed for p<0.05. Results: The study included 43 nr-axSpA patients. There was a female predom- inance with a sex ratio of 0.43. The mean age of the patients was 42±12 years [20-71] and the mean disease duration was 17±9.7 years [4-38]. The mean ESR and CRP were 2.2 mg/L [2-65] and 6.4mm/h [1-47], respectively. A higher level of acute phase reactants was found in 40.5% of cases (ESR: 35.7%, CRP: 11.9%). Forty percent of the patients had high CRP or ESR despite BASDAI<4. Accord- ing to BADSAI<4, of the 15 patients in remission, BME was displayed in 43.5% of the cases. According to the used criteria, 25.6% of the patients were in remission, of which 45.4% exhibited BME in the sacroiliac joint. There was no statistically signifcant association between disease activity according to the used defnition and the presence of BME (p=0.473). Nr-axSpa patients in remission without BME had more durable morning stiffness and articular involvement without reaching a statistically signifcant difference (p=0.361, p=0.08 respectively). Similarly, we did not fnd an association between this subgroup and sex, age, night awakenings, the presence of HLAB27 (p>0.05). Conclusion: Our study showed that even when using stringent criteria, subclin- ical remission evidenced by BME was not achieved in nr-ax SpA. Nevertheless, imaging remains one important parameter to consider in therapeutic decision making. More studies are needed to identify the best criteria for an optimal remis- sion in this population. REFERENCES: [1] Aouad K, De Craemer AS, Carron P. Can Imaging Be a Proxy for Remission in Axial Spondyloarthritis?. Rheum Dis Clin North Am. 2020;46(2):311-25. [2] Navarro-Compán V, Plasencia-Rodríguez C, de Miguel E, et al. Anti-TNF dis- continuation and tapering strategies in patients with axial spondyloarthritis: a systematic literature review. Rheumatology (Oxford). 2016;55(7):1188-94. Disclosure of Interests: None declared DOI: 10.1136/annrheumdis-2022-eular.3105 AB0821 THE FREQUENCY OF LUMBOSACRAL TRANSITIONAL VERTEBRAS IN PATIENTS WITH ANKYLOSING SPONDYLITIS N. Gokcen 1 , O. Ozdemir Isik 1 , A. Yazici 1 , A. Cefe 1 . 1 Kocaeli University Faculty of Medicine, Internal Medicine, Division of Rheumatology, Kocaeli, Turkey Background: Lumbosacral transitional vertebras (LSTVs) are anatomic varia- tions observed at L5-S1 junction (1). The prevalence of LSVT ranges from 3.9% to 35.6%, indicating that this congenital anomaly is common in general pop- ulation. LSVTs are well-defned anatomical differences causing low back pain and pelvic trauma (2). However, the studies assessing the infuence of abnormal lumbosacral anatomy on low back pain and sacroiliac joints in patients with anky- losing spondylitis (AS) are scarce (3). Objectives: The current study aimed to investigate the frequency of LSVTs and the their effects on clinical variables in AS patients. Methods: The study was designed as a prospective cross-sectional study. 113 patients were included in the study. Demographic data, clinical variables, labo- ratory results were recorded. Disease activity (ASDAS-CRP and ASDAS-ESR), patients’ functionality (BASFI, BASMI), enthesitis (Leeds enthesitis index) and quality of life (SF-36, visual analogue scale) were evaluated. The baseline pel- vic conventional radiographs and the sacroiliac magnetic resonance imaginings at the diagnosis were screened and assessed by two independent physicians. LSTVs were classifed via Castellvi classifcation. Kappa coefficient was used to fnd the interobserver reliability. Results: LSVTs were observed in 38 (33.6%) patients. Castellvi type Ia, Ib, IIa, IIb, IIIa, IIIb, and IV were found in 10 (8.8%), 7 (6.2%), 7 (6.2%), 6 (5.3%), 4 (3.5%), 1 (0.9%), and 3 (2.7%) patients, respectively. The kappa value for interobserver reliability was 0.69. There were not any differences between AS patients with and without LSVTs in terms of disease activity, functionality, and quality of life (Table 1). No statistically signifcant correlation was found between LSVTs identifed by con- ventional radiography and sacroiliitis determined by MRI. When compared the patients according to Castellvi classifcation, visual analogue scale was higher in patients with IIIa than in patients with IV (p=0.013). Disease duration was longer in patients with Ib than in patients with Ia (p=0.029). ASDAS-CRP and ASDAS-ESR were higher in patients with IIIa than in patients with IV (p=0.008 and p=0.007). Table 1. The comparison of clinical characteristics between patients with and without LSVTs Patients without LSVTs (n=75) Patients with LSVTs (n=38) p VAS 3.0 (2.0−5.0) 3.4 (1.0−6.0) 0.734 Disease duration (month) 122.0 (60.0−180.0) 120.0 (57.0−183.0) 0.834 ASDAS-CRP 1.8 (1.2−2.5) 1.8 (1.2−2.9) 0.855 ASDAS-ESR 1.6 (1.2−2.5) 1.6 (1.0−2.7) 0.976 CRP 1.8 (0.8−5.3) 2.5 (1.0−6.1) 0.471 BASMI 2.9 (2.0−4.4) 3.0 (2.1−4.0) 0.796 BASFI 1.8 (0.7−4.6) 2.1 (0.7−3.0) 0.768 SF-36 Physical function 80.0 (55.0−95.0) 80.0 (63.8−95.0) 0.765 Role physical 45.6 (0−100.0) 50.0 (25.0−100.0) 0.280 Role emotional 66.7 (0−100.0) 33.0 (0−100.0) 0.267 Energy/fatigue 50.0 (35.0−70.0) 60.0 (38.8−71.3) 0.201 Mental health 64.0 (48.0−76.0) 68.0 (52.0−80.0) 0.330 Social functioning 62.5 (50.0−87.5) 75.0 (50.0−100.0) 0.252 Body pain 67.5 (45.0−80.0) 67.5 (45.0−90.0) 0.751 General health 45.0 (35.0−65.0) 50.0 (40.0−71.3) 0.411 Values are given as median (interquartile range) Conclusion: In AS patients, the frequency of LSVT is 33.6%, which is consistent with the general population. Type I, also known as a dysplastic transverse pro- cess, is the most observed type of LSVT. The presence of LSVTs is associated neither with clinical variables nor with sacroiliitis. REFERENCES: [1] Heaps BM, Feingold JD, Swartwout E, et al. Lumbosacral Transitional Verte- brae Predict Inferior Patient-Reported Outcomes After Hip Arthroscopy. Am J Sports Med. 2020;48(13):3272-3279 [2] Matson DM, Maccormick LM, Sembrano JN, Polly DW. Sacral Dysmorphism and Lumbosacral Transitional Vertebrae (LSTV) Review. Int J Spine Surg. 2020;14(Suppl 1):14-19. Published 2020 [3] Carvajal Alegria G, Voirin-Hertz M, Garrigues F, et al. Association of lum- bosacral transitional vertebra and sacroiliitis in patients with infammatory back pain suggesting axial spondyloarthritis. Rheumatology (Oxford). 2020;59(7):1679-1683. Disclosure of Interests: None declared DOI: 10.1136/annrheumdis-2022-eular.3110 on November 2, 2023 by guest. 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