title: Motion preservation in type II odontoid fractures using temporary pedicle screw fixation: a preliminary study.
abstract: OBJECTIVE
  To assess the feasibility of temporary pedicle screw fixation for motion preservation of type II odontoid fractures unsuitable for anterior screw.
  
  
  METHODS
  Between 2012 and 2013, temporary pedicle screw fixation was performed in 13 patients with type II odontoid fractures unsuitable for anterior screw. The patients were 10 men and 3 women with an average age of 40. The implant was removed after fracture union. Dynamic CT was performed ≥ 1 month after implant removal to evaluate atlantoaxial rotation and axial neck rotation. Literature data on axial neck rotation were obtained as a historical control.
  
  
  RESULTS
  Fifty-two pedicle screws were placed successfully with satisfactory fracture reduction achieved in all patients. The average follow-up period was 14.2 months. At a mean of 9 months after the initial operation, fracture union was confirmed and implants were removed. The average total axial neck rotation was 116.5° ± 25.8° (78.2 ± 14.8 % of the historical controls). The average total atlantoaxial rotation was 34.2° ± 22.0° (27.3 ± 13.8 % of total axial neck rotation).
  
  
  CONCLUSIONS
  Temporary pedicle screw fixation is a feasible technique for motion preservation of type II odontoid fractures unsuitable for anterior screw.
authors.affiliation: Department of Orthopedic Surgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, 88 Jie Fang Road, Hangzhou, 310009, Zhejiang, People's Republic of China.
authors.forename: Bin
authors.initials: B
authors.lastname: Han
authors.forename: Fangcai
authors.initials: F
authors.lastname: Li
authors.forename: Gang
authors.initials: G
authors.lastname: Chen
authors.forename: Hao
authors.initials: H
authors.lastname: Li
authors.forename: Qixin
authors.initials: Q
authors.lastname: Chen
mesh_terms: D000328:Adult; D001268:Atlanto-Axial Joint / Q000503:physiopathology*; D020878:Device Removal; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D005593:Fracture Fixation, Internal / Q000295:instrumentation* / Q000379:methods; D017102:Fracture Healing; D006801:Humans; D008297:Male; D008875:Middle Aged; D009809:Odontoid Process / Q000293:injuries* / Q000601:surgery; D065289:Pedicle Screws; D016059:Range of Motion, Articular; D016103:Spinal Fractures / Q000601:surgery*; D016896:Treatment Outcome; D055815:Young Adult