Biomechanical Assessment Of C0-C1 Transarticular Screw Fixation

Objective To evaluate the biomachnical stability of C0-C1 transarticular screw fixation.Methods In this study, 8 fresh-frozen human cadaveric cervical spines with occiput (C0-C3) (5 men and 3 women) were used . 3 specimens were test before and after instrumentation , with either intact or C0-C1 transarticular screw, in flexion, extension, lateral bending, and torsion. then the screw pullout force were measured after fixed with C0/1 transarticular screw(A),Margle screw(B),Cl lateral mass screw(C), C2 pedical screw (D)and occiput screw(E) in 5 specimens, respectively.Results 1. C0-C1 transarticular screw fixation significantly reduced range of motion (ROM) and increased rigidity compared with the intact state in flexion (for about 19%), extension (for about 17%)and lateral bending (for about 10 %).Intensity of C0/1 transarticular fixation is also significantly higher than that of intact state for about 17% in flexion. 16% in extension ,15% in lateral banding. 2.the torsional rigidity , torsional intensity and shape-change are significantly higher than that of intact state.3.pullout force of transarticular screw is higher about 2% than Margie screw ,10% than C1 lateral mass screw, about 12% than C2 pedicle screw and 49% than occipital screw. Insignificant difference between C0/1 transarticular and Margie screw was showed. but there were statistically significant difference comparing with the other(P<0.05).Conclusion Biomachnically, the stability of C0-C1 transarticular screw fixation is a effective fixation and provides the best immediate stability .this new technique can be applied in clinic widly.