Atlantoaxial anterior transarticular screw fixation: a case series and reappraisal of the technique.

Abstract

Atlantoaxial instability is commonly treated with C1-C2 fixation performed via posterior approaches. Although anterior transarticular screw (ATS) fixation, performed with a classic retropharyngeal approach, was described more than 10 years ago, the published literature still lacks a comprehensive analysis of the procedure and a real case series. We report a series of patients treated with atlantoaxial ATS, describing the surgical procedure in detail and discussing advantages and disadvantages of the technique. The study design includes case series and technical report. We prospectively enrolled 15 patients affected by atlantoaxial instability secondary to trauma, degenerative diseases, or inflammatory diseases. Anterior transarticular screw fixation was performed with anteroposterior open-mouth and lateral intraoperative radiographs. All patients were evaluated radiologically at follow-up to identify bone fusion. Anterior transarticular screw was performed successfully in 14 patients without complications. The procedure was aborted in a case of vertebral invagination, and one case required revision surgery owing to C2 articular bone fracture. Solid C1-C2 fusion was achieved in all cases (at 10- to 21-week follow-up) except in an elderly patient affected by severe osteoporosis. No complications occurred. Although the procedure is still not widely known, ATS allows the effective and safe treatment of C1-C2 instability even in patients with systemic comorbidities. It offers several advantages over posterior approaches.