Normal magnetic resonance appearances of the temporomandibular
joints in children and young adults aged 2–18 years
Oskar W. Angenete
Thomas A. Augdal
Received: 9 August 2017 /Revised: 4 October 2017 /Accepted: 23 November 2017 /Published online: 12 December 2017
Springer-Verlag GmbH Germany, part of Springer Nature 2017
Background Knowledge of normal appearances of the temporomandibular joint (TMJ) is paramount when assessing the joint for
disease in juvenile idiopathic arthritis. Reliable features defining normal TMJs in children are limited.
Objective To establish reliable normal standards for the TMJ at magnetic resonance imaging (MRI).
Materials and methods We included children and young adults aged 2–18 years undergoing a head MRI for reasons not believed
to affect the TMJs. We assessed TMJ anatomy and contrast enhancement using a high-resolution 3-D T1-weighted sequence. We
noted joint fluid and bone marrow oedema based on a T2-weighted sequence. Three experienced radiologists read all examina-
tions twice in consensus and defined intraobserver consensus agreement.
Results We evaluated the TMJs in 101 children and young adults (45 female), mean age 10.7 years (range 2–18 years). The
intraobserver consensus agreement for the assessment of anterior condylar inclination in the sagittal/oblique plane was moderate
to good (Cohen κ=0.7 for the right side). Cohen κ for intraobserver consensus agreement for condylar shape in the coronal plane
on a 0–2 scale was 0.4 for the right and 0.6 for the left. Intraobserver agreement for measurement of joint space height and
assessment of bone marrow oedema was poor. There was a statistically significant increase in anterior inclination by age in
the sagittal plane on a 0–2 scale (P<0.0001). Eighty percent of the condyles showed a rounded shape in the coronal
plane while 20% showed mild flattening. Thirty-five of 36 right TMJs showed contrast enhancement (mild enhancement
in 32 joints, moderate in 3 joints).
Conclusion Subjective assessment of the anterior condylar inclination in the sagittal/oblique plane and condylar flattening in the
coronal plane can be considered precise features for describing TMJ anatomy in healthy children. There is an increasing anterior
inclination by age. Mild contrast enhancement of the TMJs should be considered a normal finding.
Juvenile idiopathic arthritis
Magnetic resonance imaging
* Oskar W. Angenete
Thomas A. Augdal
Department of Radiology and Nuclear Medicine,
St Olav Hospital HF, Trondheim University Hospital
Postboks 3250, Sluppen, 7006 Trondheim, Norway
Department of Circulation and Medical imaging,
Faculty of Medicine and Health Sciences
Norwegian University of Science and Technology
Department of Radiology, University Hospital of North Norway,
Department of Clinical Medicine, UiT The Arctic University of Norway,
Department of Radiology, Haukeland University Hospital,
Department of Pediatrics, St. Olavs Hospital, Trondheim, Norway
Department of Clinical Medicine, University of Bergen, Bergen, Norway
Department of Radiology, Haukeland University hospital,
Pediatric Radiology (2018) 48:341–349