SUB-AXIAL CERVICAL SPINE INSTABILITY FOLLOWING UNILATERAL FACET INJURY: A BIOMECHANICAL ANALYSIS

摘要

Unilateral facet injuries are relatively common in the sub-axial cervical spine. Facet fractures, capsular disruptions, and posterior ligament tears can all contribute to this type of injury resulting in a range of instability spanning undisplaced fractures to complete unilateral dislocations [1]. For a particular injury pattern, considerable variability exists in the choice of treatment, and the modality selected is frequently based on surgeon preference [2]. This is due, in part, to a lack of biomechanical studies focused on increasing the understanding of changes in spinal stability that occur following cervical spine injury.rnVariability in clinical management is partly due to a lack of literature. The extent of anatomical disruption secondary to this injury is poorly understood and few studies have been able to quantify the instability associated with this injury pattern [3]. Furthermore, the contribution of the posterior osteoligamentous complex to the stability of the cervical spine has not been quantified in a dynamic study.rnThe aim of this study was to examine how range of motion (ROM) and neutral zone (NZ) are altered by sequential posterior osteoligamentous disruption to a single level unilateral facet in a human cervical spine for independently simulated flexion-extension, lateral bend and axial rotation.