P015 Imaging findings in cervical spine in patients with Juvenile Idiopathic Arthritis in Tunisia

Background Juvenile Idiopathic Arthritis (JIA) is a chronic disease characterized by prolonged synovial inflammation that may cause structural joint damage. However, little is known about cervical spine involvement in JIA. The main objective of this study is to describe radiological findings of the cervical spine in patients with JIA. Methods We conduct a retrospective monocentric study. All JIA patients were included (ILAR criteria). Sociodemographic, JIA subtype, and clinical characteristics were collected. Disease activity at JIA diagnosis was evaluated by JADAS10 (Juvenile Arthritis Disease Activity Score) in poly and oligoarticular subtypes and by BASDAI (Bath Ankylosing Spondylitis Disease Activity Index) in arthritis-related enthesitis form. Cervical spine radiographs including anteroposterior and lateral with flexion views were analyzed. A p-value < 0.05 was considered significant. Results We included 25 patients (16 girls and 9 boys) diagnosed with JIA with a mean age at disease onset of 9.9 ± 3.9 [3–16]. The median disease duration was 36 months (IQR 25–75%; 30–84). The JIA subtypes were in decreasing order of frequency: Enthesitis-related Arthritis (n = 9), Oligoarticular (n = 6), Polyarticular RF- (n = 4), Polyarticular RF + (n = 2), Systemic (n = 2), Psoriatic Arthritis (n = 1), and Undifferentiated (n = 1). Median ESR and CRP were 17 mm/h [2–98] and 15.4 mg/l [0–56] respectively. The Median BASDAI score was 2.8 [1–6.3]. Median JADAS10 score was 5.3 [0–20]. Four patients (16%) were on long-term corticosteroid therapy. Five patients (20 %) have a cervical spine involvement with the following subtypes: Polyarticular (n = 2), enthesitisenthesitis-related arthritis (n = 2), and systemic (n = 1). Clinical manifestations were neck pain (n = 3) and limited range of motion (n = 4). Neurological examination noted brisk deep tendon reflexes (n = 6), positive Babinski reflex (n = 1) and positive Hoffmann reflex (n = 2). No patient had a neurological deficit. The conventional radiographs of the cervical spine showed: loss of cervical lordosis (n = 2), diastasis C1-C2 (n = 3), erosion of the odontoid process (n = 1), and anterior ankylosis (n = 3). Subsequent cervical spine MRI confirmed these findings and showed pannus at the craniocervical junction in one case and block vertebra of C6-C7 in another case. Atlanto-axial subluxation was anteroposterior in 3 patients and rotatory in one. Conclusion Cervical spine involvement is frequent and underestimated in JIA, and its radiological features are various. Hence, regular radiographic monitoring of the cervical spine is required to prevent the development of this complication.