Roentgen Analysis of Upper Cervical Spine Injuries

Abstract

Because of the structure of the upper spine, injuries in this region resulting in a disturbance of the normal relationships of the atlas, axis, and base of the skull present a special problem. In man the normal posture is erect, the centers of gravity of the head, the chest and the trunk (including the legs) lying along the vertical axis of the body, an alignment unknown in any other vertebrate. Examination of a normal spine shows the atlas, or first cervical vertebra, supporting the skull, to which it is firmly articulated, and resting below on the lateral articulations of the second cervical vertebra, or axis. That the odontoid process, or dens, takes part in the characteristic erectness or uprightness of man is evident. On examination of the normal axis, as it rests in tripod fashion on a horizontal plane surface, the dens is seen to be vertical. With the head in a normal upright position, the atlas ring should therefore rotate in a horizontal plane, and a vertical transverse plane passed through the c...