A Biomechanical Comparison Between Modern Anterior Versus Posterior Plate Fixation of Unstable Cervical Spine Injuries

Abstract

Abstract Unstable cervical spine injuries include flexion-distraction injuries with unilateral or bilateral facet dislocations and burst fracture of the vertebral body. These unstable injuries have been treated in various ways. For instance, various posterior fixation methods have been available, and particularly plating with lateral mass screws was proved to provide a rigid fixation. However, most cervical decompressions need to be performed anteriorly because the majority of compression is caused by either vertebral body retro-pulsion or herniated disc material (anterior structure). Anterior plating technique was recently introduced and employed for the surgical treatment of unstable injuries. Anterior plating is thought to offer an acceptable stability through a single surgical approach, but additional posterior fixation is frequently recommend to achieve a sufficient stability. There is a paucity of data on a direct biomechanical comparison of the stiffness provided by modern anterior, posterior, or combined plate-screw fixation in a human cadaveric cervical spine model. The purpose of this study was to compare the biomechanical characteristics of anterior vs posterior plating constructs and to evaluate the stiffness of a combined anterior-posterior fixation construct in a clinically simulated flexion-distraction injury and burst fracture models of the cervical spine.