# Anterior Odontoid Screw Fixation for Trauma: Case Series and Technical Considerations

## TL;DR

This study evaluates the effectiveness of anterior odontoid screw fixation for treating type II odontoid fractures, showing high fusion rates and preserved motion.

## Contribution

The study provides a single-center case series demonstrating the safety and efficacy of anterior odontoid screw fixation for type II odontoid fractures.

## Key findings

- AOSF achieved a 90% solid fusion rate with minimal postoperative fracture gap and angulation.
- Precise anatomical reduction (<2 mm gap, <5–10° angulation) was critical for successful fusion outcomes.
- No major complications were observed in patients undergoing AOSF.

## Abstract

Background/Objectives: Odontoid fractures—prevalently Anderson–D’Alonzo type II—are clinically relevant for their biomechanical instability and risk of non-union. Posterior C1–C2 fusion yields the highest fusion rates but sacrifices atlantoaxial rotation. Anterior odontoid screw fixation (AOSF) enables direct osteosynthesis while preserving motion. This study aimed to evaluate the radiographic outcomes, fusion rate, and technical considerations of AOSF in a consecutive single-center series, highlighting anatomical and procedural factors influencing bone healing. Methods: Retrospective, single-center case series of patients who underwent AOSF for acute type II odontoid fractures (2018–2024). Inclusion criteria included CT-confirmed fractures with reducible alignment. Radiographic parameters (fracture gap and angulation) were measured on standardized sagittal CT reconstructions. Outcomes were evaluated at 6 weeks, 3 months, and 6 months. Mean follow-up was 24 months. Results: The mean fracture gap decreased from 5.3 mm preoperatively to 0.8 mm postoperatively, and angulation from 27.8° to 3.5° (p < 0.0001). Nine of ten patients (90%) achieved solid fusion; one required secondary posterior fixation. No intra- or postoperative infections, neurovascular injuries, or neurological deficits were observed. Conclusions: AOSF is a safe and effective motion-preserving technique in appropriately selected Grauer IIA/IIB fractures. Precise anatomical reduction (<2 mm gap, <5–10° angulation) is a key predictor of successful fusion, even in elderly patients. Future multicenter studies with larger cohorts and standardized clinical outcome measures are needed to validate radiographic thresholds and optimize patient selection.