Fracture of the anterior arch of the atlas associated with a congenital cleft of the posterior arch. Demonstration by CT.

A case of a vertical fracture of the anterior arch of the atlas associated with a congenital cleft of the posterior arch of the same vertebra is reported. Such an association has not previously been described in the literature. X-Ray computed tomography is an excellent exam for visualizing this region and for easily distinguishing between fractures and congenital clefts.