title: Surgical Treatment of Occipitocervical Dislocation with Atlas Assimilation and Klippel-Feil Syndrome Using Occipitalized C1 Lateral Mass and C2 Fixation and Reduction Technique.
abstract: OBJECTIVE
  To introduce and assess a surgical treatment of occipitocervical (OC) dislocation with atlas assimilation and Klippel-Feil syndrome (KFS) using occipitalized C1 lateral mass and C2 fixation and reduction technique.
  
  
  METHODS
  From January 2007 to August 2013, 58 symptomatic patients with OC dislocation and KFS of C2-3 congenital fusion and atlas assimilation were surgically treated in our institution via this technique. After opening the C1-2 facet joints via a posterior approach, OC reduction was conducted by intraoperative manipulation and C1 lateral mass and C2 pedicle screw and rod fixation. The instrument position, fusion status, and clinical outcome were analyzed.
  
  
  RESULTS
  The average follow-up was 36 months (range, 18-52 months). Radiologically, effective reduction was achieved in 56 patients (96.6%) and <50% reduction in 2 (3.4%) who had additional transoral decompression. Neurologic improvement and solid bone fusion were achieved in all patients. The clinical symptoms improved for all patients, with the averaged Japanese Orthopedic Association myelopathy scores increasing from 11.5 to 15.6 (P < 0.01).
  
  
  CONCLUSIONS
  In patients with OC dislocation and KFS of C2-3 fusion and atlas assimilation, posterior manipulative reduction combined with occipitalized C1 lateral mass and C2 fixation provides a reliable and effective treatment.
authors.affiliation: Department of Neurosurgery, PLA General Hospital, Beijing, China.
authors.forename: Yi-Heng
authors.initials: YH
authors.lastname: Yin
authors.affiliation: Department of Neurosurgery, PLA General Hospital, Beijing, China. Electronic address: neuroplahp@126.com.
authors.forename: Guang-Yu
authors.initials: GY
authors.lastname: Qiao
authors.affiliation: Department of Neurosurgery, PLA General Hospital, Beijing, China. Electronic address: xg_yu@aliyun.com.
authors.forename: Xin-Guang
authors.initials: XG
authors.lastname: Yu
mesh_terms: D000293:Adolescent; D000328:Adult; D001269:Atlanto-Occipital Joint / Q000000981:diagnostic imaging / Q000601:surgery*; D001368:Axis, Cervical Vertebra / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000601:surgery; D001270:Cervical Atlas / Q000000981:diagnostic imaging / Q000601:surgery; D002574:Cervical Vertebrae / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000601:surgery*; D005260:Female; D006801:Humans; D016268:Internal Fixators; D004204:Joint Dislocations / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery*; D007714:Klippel-Feil Syndrome / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D065289:Pedicle Screws; D012189:Retrospective Studies; D013123:Spinal Fusion / Q000379:methods*; D016896:Treatment Outcome; D055815:Young Adult
keywords: Atlas assimilation; C2-3 congenital fusion; Klippel-Feil syndrome; Occipitocervical dislocation; Reduction