TABLE 112.7 RADIOGRAPHIC CHARACTERISTICS OF PEDIATRIC CERVICAL SPINE Cartilage artifact Tapered anterior vertebrae Apparently absent ring of C1 Atlas (C1) body not ossified at birth and may fail to close Axis (C2) has four ossification centers Apex of odontoid ossifies between 12 and 15 yrs of age Spinous process ossification centers Increased mobility Pseudosubluxation C1 override on dens Increased predental space (5 mm maximum) Ligament laxity Facet joints shallow Growth plates (synchondrosis) Dens ossifies between and yrs of age (may persist into young adults) Posterior arch of C1 ossifies at yrs of age Anterior arch of C1 ossifies at 6–9 yrs of age C1 reaches adult size at 3–4 yrs of age C2 through C7 reach adult size at 5–6 yrs of age Lack of cervical lordosis Fulcrum varies with age Soft tissue variability with respiration Congenital clefts or other bony abnormalities (os odontoideum, spondylolisthesis, spina bifida, ossiculum terminale) The bones should be evaluated for typical abnormalities, realizing that these may be subtle Acute fractures are often irregular in location and appearance without sclerosis as compared with the more routine locations and appearance of cartilaginous growth areas The clinician should be aware that structures that overlay the spine, including the skull and the teeth, might simulate fractures If further information about C1–C2 or any other portion of cervical spine is required, a CT scan should be considered While it is more expensive than a plain radiograph, it is relatively easy to obtain, offers enhanced and more consistent