FIGURE 112.16 The ABCS of radiographic cervical spine interpretation When evaluating a lateral cervical spine radiograph, the clinician must ensure that C1–C7 are included as well as the C7–T1 junction An adequate open-mouth view is often technically difficult to obtain in young children and those who are intubated A systematic approach should be used when evaluating radiographs of the cervical spine The ABCS method is a useful approach ( Fig 112.16 ) Alignment is assessed as demonstrated in Figure 112.17 , keeping in mind that the spinal cord lies between the posterior spinal line and the spinolaminar line These lordotic curves may not be present in children younger than years, those on hard spine boards or on cervical collars, or those with cervical neck muscle spasm Gross malalignment should be detectable with this assessment Be aware of physiologic pseudosubluxation of C2 on C3 and less frequently, C3 on C4 To discern whether there is pseudosubluxation or traumatic injury, determine the distance between the posterior arch of C2 and the spinolaminar line; if it is greater than mm, true injury should be considered ( Fig 112.18 )