Congenital spondylolisthesis of the 6th cervical vertebra: CT findings.

The CT demonstration of a case of congenital spondylolisthesis of the C6 vertebral body is reported. This entity includes bilateral bony defects in the pars interarticularis regions, deranged facet joints, as well as a midline bony cleft in the spinous process. This congenital deformity should be recognized and not mistaken for traumatic spondylolisthesis.