BACKGROUND AND PURPOSE:As the standard of care for the evaluation of the cervical spine shifts from plain radiographs to multidetector row CT (MDCT), a re-examination of the normal anatomic relationships of the occipitovertebral articulations is needed. We aimed to define the normal anatomic relationships of craniocervical articulations on MDCT and address any discrepancies with currently accepted ranges of normal on plain radiographs.

BACKGROUND AND PURPOSE:Analysis of the prevertebral soft tissue (PVST) is helpful in detecting osseous and ligamentous injuries of the cervical spine. Because the standard of care has shifted from radiographs to multidetector CT (MDCT), a re-examination of the PVST on MDCT images is needed to establish normal values for thickness appropriate for this imaging technique.

Normal values for the craniocervical junction articulations and relationships as seen on MDCT are different from the accepted ranges of normal based on radiographs. The values should be considered the normal values in the pediatric population on MDCT.

We propose that the obtained normal values be considered as the upper limits of the normal range for the atlantoaxial interval in adult and pediatric populations on MDCT images.