Magnetic resonance imaging of temporomandibular joints in children with arthritis

Purpose: The aim of the present study was to describe the gadolinium-enhanced magnetic resonance imaging (MRI) features of temporomandibular joints (TMJs) in children with arthritis. These findings would facilitate the early diagnosis of disease and/or relapse.

Materials and methods: In the present retrospective study, 2 pediatric radiologists reviewed consecutive MRI scans of the TMJs of children with a definitive diagnosis of juvenile idiopathic arthritis (JIA), including oligoarthritis, polyarthritis, and juvenile psoriatic arthritis. For each MRI scan, specific criteria were evaluated, including the condylar head, condylar fossa, articular eminence, disk shape and position, joint effusion, synovium, intra-articular space, and jaw motion.

Results: A total of 48 patients with mean age of 11.2 years who had been diagnosed with JIA were reviewed. The most common abnormal findings (in order of frequency) were erosion of the condylar head (n = 38), synovial enhancement (n = 35), articular surface flattening (n = 20), abnormalities in jaw motion (n = 26), intra-articular space enhancement (n = 20), subchondral sclerosis of articular eminence (n = 12), joint effusion (n = 9), deformed/displaced disk in the open or closed position (n = 9), bone marrow edema (n = 8), sclerosis of fossa (n = 3), sclerosis of head (n = 3), and the presence of osteophytes (n = 1). Comparing each category of MRI findings, no significant gender differences were found.

Conclusions: Children with JIA who have undergone MRI of their TMJs typically present with more than 1 abnormal radiographic finding consistent with synovitis. Although the presence or absence of each MRI finding did not differ among the arthritis types, bilateral synovial enhancement and bilateral condylar head articular surface flattening were more common in JIA than in juvenile psoriatic arthritis. These findings suggest that MRI should play an important role in the diagnosis and assessment of TMJ involvement in children with JIA.