title: Atlantoaxial subluxation associated with ossification of posterior longitudinal ligament of the cervical spine.
abstract: METHODS
  Two case reports.
  
  
  OBJECTIVE
  To demonstrate two rare cases of atlantoaxial subluxation associated with ossification of the posterior longitudinal ligament of the cervical spine, in which spastic quadriplegia developed.
  
  
  BACKGROUND
  There are only two reports of an association of diffuse idiopathic skeletal hyperostosis with atlantoaxial subluxation. This condition often accompanies ossification of the posterior longitudinal ligament of the cervical spine, but there is nothing in the literature about the association of ossification of the posterior longitudinal ligament with atlantoaxial subluxation.
  
  
  METHODS
  Clinical and radiographic findings of these two cases were demonstrated. In both cases laminoplasty of the cervical spine was performed with occipitoaxial arthrodesis.
  
  
  RESULTS
  The spastic quadriplegia of these two patients caused by myelocompression improved after surgical intervention.
  
  
  CONCLUSIONS
  Ossification of the posterior longitudinal ligament of the cervical spine may cause atlantoaxial subluxation.
authors.affiliation: Department of Orthopaedic Surgery, Oita Medical University, Japan. Takasita@oita-med.ac.jp
authors.forename: M
authors.initials: M
authors.lastname: Takasita
authors.forename: H
authors.initials: H
authors.lastname: Matsumoto
authors.forename: S
authors.initials: S
authors.lastname: Uchinou
authors.forename: H
authors.initials: H
authors.lastname: Tsumura
authors.forename: T
authors.initials: T
authors.lastname: Torisu
mesh_terms: D000368:Aged; D001368:Axis, Cervical Vertebra / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D001270:Cervical Atlas / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D016916:Joint Deformities, Acquired / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D007593:Joint Instability / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D017887:Ossification of Posterior Longitudinal Ligament / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D011859:Radiography