To describe the clinical and laboratory characteristic, state the treatment and outcome of patients with juvenile idiopathic arthritis 
A retrospective cross-sectional study of children diagnosed with JIA was assessed at King Abdullah Specialist Children's Hospital, Riyadh, Saudi Arabia (2015-2019), which included a descriptive analysis of children who had TMJ involvement among our study group. Subjects diagnosed with the TMJ arthritis were based either on clinical musculoskeletal examination or using contrast-enhanced MRI.
We reviewed 123 cases with different JIA subtypes (57% females). The most frequent subtype is the oligoarticular (36%). TMJ involvement was found in 16% (n=20/123) of the patients, of whom 45% had Polyarticular JIA. The rheumatoid factor was positive in 25%; antinuclear antibody (ANA) in 45% and none showed positivity to HLAB27. Treatment resulted in complete resolution in 95% of cases, while Micrognathia and obstructive sleep apnea were the complications reported in 5% of cases.
TMJ involvement in JIA is not uncommon. Females with polyarticular disease were more frequently affected with TMJ arthritis. Positive ANA could be a risk factor for TMJ involvement, while positive HLAB27 might have some protective effects. Early treatment for TMJ arthritis is essential to avoid possible complications.