title: Caudally Directed Inferior Facetal and Transfacetal Screws for C1-C2 and C1-2-3 Fixation.
abstract: An alternative caudally directed C2 inferior facetal screw is described. Such screw insertion can form the axial stabilization point in cases undergoing atlantoaxial lateral mass plate/rod and screw fixation and those undergoing C1-2 and C1-2-3 spinal fixation. The C2 screw courses from the medial point of the pedicle-laminar junction and travels caudally and laterally toward the C2-3 articulation. Deploying a longer screw that traverses in a transarticular fashion into the facetal mass of C3 vertebra, one can perform C1-2-3 stabilization. Sixteen patients underwent C2 inferior facetal or C2-3 transarticular screw in combination with a C1 screw for atlantoaxial fixation. Three of these patients with multilevel spinal instability underwent atlantoaxial and C2-3 fixation using the discussed technique. The technical issues, anatomic subtleties, and indication for use of the C2 inferior facetal screws are discussed. With an average follow-up of 9 months, all screws have successfully provided stability that resulted in arthrodesis of the treated spinal segments. A caudally directed C2 inferior facetal screw can enhance the armamentarium of the surgeon, provide an alternative to conventional techniques or a bailout option, and add to the safety of the procedure of atlantoaxial lateral mass fixation in anatomically challenged situations.
authors.affiliation: Department of Neurosurgery, Seth G. S. Medical College and K. E. M Hospital, Parel, Mumbai. Electronic address: atulgoel62@hotmail.com.
authors.forename: Atul
authors.initials: A
authors.lastname: Goel
mesh_terms: D001268:Atlanto-Axial Joint / Q000293:injuries* / Q000601:surgery*; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery; D019544:Equipment Failure Analysis; D005593:Fracture Fixation, Internal / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D004204:Joint Dislocations / Q000000981:diagnostic imaging / Q000601:surgery*; D065289:Pedicle Screws; D011474:Prosthesis Design; D016103:Spinal Fractures / Q000000981:diagnostic imaging / Q000601:surgery*; D016896:Treatment Outcome
keywords: Atlantoaxial fixation; Atlantoaxial instability; Atlas; Axis; Vertebral artery