Spondylolysis of the axis. A case report and review of the literature.

Bilateral congenital defects in the pedicles of the second cervical vertebra were noted on conventional X-rays and tomography of a 42-year-old male. He had been assaulted after which he suffered upper neck and occipital pain. Subsequent CT scanning demonstrated the incomplete nature of the axis defects. This is felt to be important in prognosticating the likelihood of spondylolisthesis formation and counselling the patient with regard to acceptable future physical activity. The role of CT examination for this purpose has not been stressed before. The importance of differentiation from old trauma is emphasized.