Atlantoaxial Instability: Biomechanical Evaluation of T-plate Versus Transarticular Screw Fixation
Background Context: Transarticular fixation has yielded serious complications such as hardware failure, hypoglosal nerve injury and vertebral artery laceration lowering its widespread acceptance. Purpose: Our objective was to evaluate the T plate construct for the atlantoaxial fusion in comparison with the Magerl technique. Study Design: Pullout tests were performed on cadaverous specimens to compare the fixation strength of T-plate fixation versus Magerl technique. Methods: The study was performed on 18 intact specimens. Pullout tests were performed on a MTS machine. Results: The mean failure load for the T plate fixation (mean=318.83 N, SD=46.61N) is lower than for the transarticular fixation (mean =520.07 N, SD=194.51 N). Conclusion: Posterior cervical plating offers a reasonable alternative for the clinical situations in which the placement of the transarticular screws is contraindicated. The safe placement of the screws is the main advantage of the T-plate construct versus the transarticular screw fixation. Ongoing research will evaluate the optimal screw length placed on C1 and C2 for the T-plate fixation.
School:University of Toledo Health Science Campus
School Location:USA - Ohio
Source Type:Master's Thesis
Keywords:cervical spine posterior fusion t plate transarticular screw biomechanics cadaveric study
Date of Publication:01/01/2005