Fully percutaneous posterior transarticular C1-C2 stand-alone screw instrumentation: A case series and technical note.

Magerl's technique remains a widely accepted method for achieving C1-C2 fusion. Although two approaches using intermuscular corridors and biplanar X-ray guidance have been reported, there are no published studies dedicated to fully percutaneous techniques employing cannulated screws.

Objective: To demonstrate the feasibility of a fully percutaneous C1-C2 fixation technique using cannulated screws and to analyze the short- and long-term outcomes of the initial case series.

Material and methods: This case series included patients over 15 years of age who were presented with acute or subacute atlantoaxial instability at C1-C2 due to fractures of the odontoid process, C1 vertebra, or C2 vertebral body. Surgical details and fusion criteria were described. Due to the absence of comparison groups, only descriptive statistical methods were employed.

Results: A total of 11 patients (8 men, 3 women; mean age 41.5 ± 18.2 years) underwent fully percutaneous transarticular C1-C2 fixation. The mean operative time was 115.0 ± 30.8 min for patients stabilized using a Halo device and 80.6 ± 33.2 min for those immobilized with a Mayfield clamp. The mean blood loss across all cases was 38.8 ± 8.7 mL. One patient died from concurrent cardiac pathology. Two patients were lost to follow-up due to relocation, leaving 8 patients for final assessment. At final follow-up, the mean VAS score was 2 ± 1.5 and the mean NDI score was 5.3 ± 5.2. All patients with preoperative neurological deficits improved by one level on the ASIA scale. Fusion was achieved in 7 of 8 cases (87.5%), and 1 patient (12.5%) developed a stable C1-C2 pseudoarthrosis.

Conclusion: Our initial clinical experience demonstrated that fully percutaneous posterior transarticular C1-C2 stand-alone screw fixation using cannulated instruments could be a feasible and safe procedure. Critical requirements for this technique include complete reduction of atlantoaxial dislocation, compression in the lateral joint region, adequate intraoperative visualization, and strict adherence to specific screw trajectories.