Abstract

The knowledge of the kinematics of the cervical spine is a very important tool, since this region is one of the more complex structures of the human skeleton and because the incidence of failure that may result from trauma or degenerative diseases is relatively high. The main objective of this study is the analysis and comparison of anterior cervical fusion and/or posterior cervical fusion as possible treatments for a fracture of type C2.2 according to AO spine injury classification system, and this study may assist health professionals in choosing the best fusion technique. To this end we built a 3 D finite element model of the cervical segment C4‐C5‐C6. Their intervertebral discs (IV ) and its components, namely the nucleus pulposus, the annulus fibrosus, the fibers and the lamellar cartilaginous plates were modeled. Six sets of ligaments (anterior longitudinal, posterior longitudinal, interspinous, suprespinous, yellow and capsular) and the facet joints were also modeled. The simulation of the fracture was performed in 3 different steps: introduction of a fracture zone in the previous C5 vertebra, rupture of the ligaments of the posterior region and the sliding of the C5 vertebra. The instrumentation used in the study treatments and even the replacement of the damaged disc by bone graft from the iliac bone, were also modeled. Analyzing the displacements of the functional unit it was concluded that the anterior and posterior cervical fusion provides the best results compared to other types of cervical fusion studied in terms of displacement of the functional unit.