ABSTRACT
The cranial-vertebral junction (CVJ) is a complex structure consisting of the occiput, atlas, and axis, along with an array of ligaments that allow mobility and stability of the articulating surfaces. CVJ instability is frequently secondary to trauma such as atlanto-occipital dislocation, type III occipital condyle fractures, complex atlas/axis fractures, and ligamentous instability. The relative contraindications for revision of a CVJ nonunion are rare, given the fact that the primary procedure was performed for pathology that mandated a fusion. Prompt radiographic evaluation of the CVJ following the turn to prone position is very important to minimize neurologic injury in the unstable patient. Reliance on the many fibrin glue adjuncts and dural onlay grafts to prevent the development of a pseudomeningocele without primary closure will often disappoint both the patient and the surgeon. A computed tomography scan of the CVJ is usually performed 1 year after surgery to verify fusion.
