The evolution of posterior cervical and occipitocervical fusion and instrumentation.

The past several decades have been the setting for a remarkable evolution of spinal instrumentation technology. The advancements that have been made have allowed previously complex disorders of the cervical spine, the atlantoaxial articulation, and the occipitocervical junction to be managed more effectively with direct methods of internal fixation and arthrodesis. This has resulted in improvements in patient outcomes and fusion success rates. The improved strength of instrumentation constructs allows minimal, if any, external bracing, obviating the need for a halo orthosis in many cases. In this paper the authors review key events that have occurred in neuroimaging, biomechanical testing, and the development of fusion and instrumentation constructs.