title: Feasibility of C2 translaminar screw as an alternative or salvage of C2 pedicle screws in atlantoaxial instability.
abstract: METHODS
  A retrospective outcome study.
  
  
  OBJECTIVE
  The purpose of this study was to analyze the clinical outcomes of our experience with the C2 translaminar screw technique and evaluate its feasibility as an alternative or salvage of the pedicle screw.
  
  
  BACKGROUND
  Pedicle screws are the most biomechanically stable screws for use in atlantoaxial fixation. However, in cases with elevated risk of neurovascular complications or failure of screw insertion attempts, a reliable alternative technique is required.
  
  
  METHODS
  Fourteen patients with atlantoaxial instability underwent posterior fixation with C2 translaminar screws. Indications included traumatic instability, atlantoaxial subluxation, os odontoideum, and fusion failure after anterior fixation of a type II odontoid process fracture. A total of 26 screws were inserted and all patients were assessed both clinically and radiographically.
  
  
  RESULTS
  No procedure-related complications or hardware failures were observed during the follow-up. Postoperative computed tomographic scans revealed laminar breach in 3 patients and none of these resulted in neurological symptoms. Radiographically demonstrated bony fusion was established in 11 patients (91.7%) at follow-up over 6 months, and 5 patients with initial neurological deficit demonstrated at least 1 grade improvement by Frankel grade.
  
  
  CONCLUSIONS
  C2 translaminar screws provide surgeons with an expanded option for posterior fusion in high cervical lesions. This technique is safe and easy to adopt with a favorable rate of successful fusion. We believe that preoperative planning using computed tomographic scan is mandatory and use of an additional connector may reduce the stress and strain of the screws.
authors.affiliation: Department of Neurosurgery, Kyungpook National University Hospital, Daegu, South Korea.
authors.forename: Jae Suk
authors.initials: JS
authors.lastname: Park
authors.forename: Dae-Chul
authors.initials: DC
authors.lastname: Cho
authors.forename: Joo Kyung
authors.initials: JK
authors.lastname: Sung
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001268:Atlanto-Axial Joint / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D001368:Axis, Cervical Vertebra / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D001863:Bone Screws / Q000592:standards* / Q000639:trends; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012189:Retrospective Studies; D016103:Spinal Fractures / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D013123:Spinal Fusion / Q000295:instrumentation / Q000379:methods*