title: Atlantoaxial anterior transarticular screw fixation: a case series and reappraisal of the technique.
abstract: BACKGROUND
  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.
  
  
  OBJECTIVE
  We report a series of patients treated with atlantoaxial ATS, describing the surgical procedure in detail and discussing advantages and disadvantages of the technique.
  
  
  METHODS
  The study design includes case series and technical report.
  
  
  METHODS
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Neurosurgery, Neuroscienze Salute Mentale e Organi di Senso (NESMOS) Department, Faculty of Medicine and Psychology, "Sapienza" University of Rome, via di Grottarossa 1035-1039, 00189 Rome, Italy. Electronic address: fmpolli@libero.it.
authors.forename: Filippo Maria
authors.initials: FM
authors.lastname: Polli
authors.affiliation: Department of Medico-Surgical Sciences and Biotechnologies, "Sapienza" University of Rome, Corso della Repubblica 79, 04100 Latina, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Miscusi
authors.affiliation: Neurosurgery, Neuroscienze Salute Mentale e Organi di Senso (NESMOS) Department, Faculty of Medicine and Psychology, "Sapienza" University of Rome, via di Grottarossa 1035-1039, 00189 Rome, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Forcato
authors.affiliation: Neurosurgery, Neuroscienze Salute Mentale e Organi di Senso (NESMOS) Department, Faculty of Medicine and Psychology, "Sapienza" University of Rome, via di Grottarossa 1035-1039, 00189 Rome, Italy.
authors.forename: Antonino
authors.initials: A
authors.lastname: Raco
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001268:Atlanto-Axial Joint / Q000601:surgery*; D001863:Bone Screws; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D013123:Spinal Fusion / Q000379:methods*; D016896:Treatment Outcome
keywords: Atlantoaxial instability; Atlantoaxial screw fixation; Atlas; Axis; Craniocervical junction; Transarticular screw fixation