title: [Percutaneous microendoscopic anterior release, fixation and fusion for irreducible atlanto-axial dislocation].
abstract: OBJECTIVE
  To evaluate the safety and efficacy of one-stage percutaneous microendoscopic anterior release, trans-articular fixation and fusion to reduce and stabilize for irreducible atlanto-axial dislocation.
  
  
  METHODS
  Eight consecutive patients were treated by percutaneous microendoscopic anterior release, trans-articular C(1-2) fixation and bone graft fusion. The mean age was 33 years (range, 28-52 years). The pathology included odontoid dysplasia in 3 patients, chronic odontoid fractures in 2, odontoid absence in 1, fasilar impression in 1 and malunion of odontoid fracture in 1. The classification of disability was that proposed by Symon and Lavender. There were moderate disability in 4, severe non-bedbound in 3, and severe bedridden in 1.
  
  
  RESULTS
  The new technique was performed successfully in all cases. All patients underwent trans-articular C(1-2) screw fixation and anterior bone graft fusion. The average operation time was 120 min (90-150 min), and the average estimated blood loss was 150 ml (100-250 ml). Seven cases resulted in anatomic reduction, 1 had partial reduction. The follow-up period was 8-16 months. The effective rate was 100%, and the excellent rate was 51.25%; the average improvement rate for the spinal canal decompression was 76.5%. There was no instrument failure or pseudarthrosis, and solid fusion was achieved in the all cases. The loss of axial rotation of cervical spine was 30-40 degrees .
  
  
  CONCLUSIONS
  Percutaneous microendoscopic anterior release, fixation and fusion is an effective, reliable, and safe procedure for the treatment of irreducible atlanto-axial dislocation.
authors.affiliation: Department of Orthopaedic, the Second Affiliated Hospital, Wenzhou Medical College, Wenzhou 325027, China. feygk@163.com
authors.forename: Yong-long
authors.initials: YL
authors.lastname: Chi
authors.forename: Hua-zi
authors.initials: HZ
authors.lastname: Xu
authors.forename: Yan
authors.initials: Y
authors.lastname: Lin
authors.forename: Qi-shan
authors.initials: QS
authors.lastname: Huang
authors.forename: Fang-min
authors.initials: FM
authors.lastname: Mao
authors.forename: Xiang-yang
authors.initials: XY
authors.lastname: Wang
authors.forename: Wen-fei
authors.initials: WF
authors.lastname: Ni
mesh_terms: D000328:Adult; D001268:Atlanto-Axial Joint; D004724:Endoscopy / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D005593:Fracture Fixation, Internal / Q000379:methods*; D006801:Humans; D004204:Joint Dislocations / Q000601:surgery*; D008297:Male; D008866:Microsurgery; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000379:methods; D013123:Spinal Fusion / Q000379:methods*; D016896:Treatment Outcome