Comparison of Two Posterior Three-Point Fixation Techniques for Treating Reducible Atlantoaxial Dislocation

Abstract

Study design: Retrospective comparative study.

Objective: To compare the outcomes of C1-C2 transarticular screw combined with C1 laminar hook (TAS+C1H) and C1-C2 transarticular screw combined with modified Gallie technique (TAS+G) for treating reducible atlantoaxial dislocation (AAD).

Summary of background data: Both TAS+C1H and TAS+G fixation were 3-point fixation techniques for AAD. TAS+C1H technique was comparable to TAS+G technique in biomechanics. However, it is unknown whether it can achieve same outcomes as TAS+G technique.

Methods: Data of the 63 patients who underwent TAS+C1H or TAS+G fixation and fusion because of AAD were retrospectively reviewed. Bone fusion time was recorded. The outcomes evaluated by visual analog scale score for neck pain (VASSNP), Nurick scale, neck stiffness (none/mild/severe), patient satisfaction, and Neck Disability Index (NDI) were compared between two groups.

Results: At the final follow-up, bone graft fusion rates were 100% in both groups (P > 0.05). Nurick scales were significantly improved in both groups (P < 0.05), but with no significant differences between groups (P > 0.05). There were no significant differences between two groups in VASSNP, neck stiffness, patient satisfaction, or NDI (all P > 0.05). There were no complications related to the surgical approach and instrumentation in either group.

Conclusion: Both TAS+C1H and TAS+G fixation were effective in the treatment of reducible AAD. TAS+C1H was safer than TAS+G because it could potentially reduce the risk of spinal cord and venous plexus injury associated with sublaminar cables.

Level of evidence: 3.