Biomechanical Study of Finite Element Method on Novel Composite Anterior Cervical Spine Fixation Techniques

This study was to compare the biomechanical properties of 4 internal fixation methods on the lower cervical injury model by finite element method.

Using the finite element method to study the biomechanical characteristics of the novel composite anterior cervical spine fixation technique-combining anterior transpedicular screw fixation with a zero-track internal fixation.

Several studies have demonstrated lower cervical 3-column injury is not effective treated by anterior cervical surgery. To the best of our knowledge, few studies has examined the effectiveness of enhanced anterior cervical surgery alone.

CT data of a healthy 28-year-old male adult were selected to create finite element models of a 3-column injury model of the lower cervical spine. Four internal fixation methods were applied to the lower cervical spine injury model: anterior cervical locking plate model (group A), posterior transpedicular screw fixation model (group B), anterior+posterior transpedicular screw fixation model (group C), and the novel composite anterior cervical spine fixation model (group D). These models were subjected to 75 N axial force and 1.0 Nm to induce various movements. Comparing the range of motion (ROM), vertebral displacement, and stress distribution of the different models under various conditions.

Compared with the normal model, in flexion, extension, rotation, and lateral bending, the overall intervertebral mobility of group D demonstrated less ROM, but a slightly larger than group C. In flexion, rotation, and lateral bending, the peak stresses for group D were less than group B. In flexion and extension, the vertebral displacements of C3-6 in group D showed less displacement, but a slightly larger than group C.

The biomechanical characteristics of the new composite anterior cervical fixation method are favorable.

Level III.