Results of instrumentation removal after temporary C1–C2 fixation in C2 odontoid fracture: a retrospective cohort study

Objective. To study clinical, including functional, outcomes after instrumentation removal in patients who underwent temporary posterior C1–C2 fixation without fusion for odontoid process fracture and to compare them with the results of treatment of patients without instrumentation removal.

Material and Methods. Design: Retrospective comparative study in a single-center cohort. Posterior C1–C2 fixation without spinal fusion was performed in 85 patients in 2009–2024. After applying the compliance criteria, 49 patients with C2 odontoid fracture were included in the comparative analysis, of which 22 underwent instrumentation removal after confirmed consolidation of the fracture, and in 27 patients the instrumentation was not removed. Age, sex, injury mechanism, fracture type, and time to fracture consolidation were assessed in both groups. Assessed parameters included pain intensity according to VAS, total neck rotation, rotational range of motion in the C1–C2 segment according to functional CT, as well as subjective stiffness during head rotation. The follow-up time points were 3, 6, and 12 months.

Results. At 6 and 12 months after instrumentation removal, patients showed a statistically significant decrease in pain intensity as compared with the group without removal. Total neck rotation in the removal group increased progressively and was significantly higher after 12 months than in patients with retained fixation. The removal group also showed a marked decrease in subjective stiffness. No clinically significant perioperative complications requiring additional treatment or repeat intervention were registered. The obtained data may be used in neurosurgery when choosing treatment tactics for patients with C2 odontoid process fractures, especially in cases where the priority is to preserve or restore the rotational function of the upper cervical spine.

Conclusion. Instrumentation removal after temporary posterior C1–C2 fixation and confirmed consolidation of C2 fracture is associated with partial restoration of rotational mobility, reduction of subjective stiffness, and decrease in pain intensity at follow-up periods of up to 12 months.

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