Posterior Atlantoaxial Fixation: Can We Improve the Success and Reduce Failure?

Introduction: Treatment of C1/2 subluxation (AAS) and odontoid fractures can be achieved by posterior C1/2 fixation. However, failure rates of up to 24% were reported. We used a modified fixation technique in 39 consecutive patients to improve these results.

Methods: A prospective observational study design.

Technique: Patients were positioned prone, C1 and C2 were exposed posteriorly, and a loop of wire was passed under C1 and tightened behind the spinous process of C2. C1 and C2 were prepared for bone graft chips obtained from C6 or C7 spines. The construct was supported by bone cement.

Results: Thirty-nine patients of which 24 had rheumatoid AAS. Mean age was 59.5 years (SD = 12.43). In 91.66%, stability was achieved and 91% demonstrated bony fusion on follow-up radiography. Two failed and required reoperation. No postoperative neurological deficits were encountered in any of the patients.

Conclusion: The aforementioned modified C1-C2 fixation had a very high success rate and a very low failure rate.