Fissures across the vertebral articular processes may be formed by the presence of an ununited accessory center of ossification opposite the tips of the articular processes, or they may be the result of fracture of the articular processes. The differentiation between these anomalies and isolated fractures of the vertebral articular processes can nearly always be made, but even in the literature considerable confusion exists in making the distinction, and anomalies have been mistaken for fractures. If proper value is given to the history of the injury and to the appearance in the roentgenograms, such mistakes are preventable.
Much more common than fractures are the fissures due to anomalies which arise because of an accessory center of ossification opposite the tip of an articular process in the lumbar region. Such fissures are usually transverse, well demarcated and often bilateral or multiple. There are, however, variations which are shown in