title: Anterior cervical discectomy and fusion using a stand-alone polyetheretherketone cage packed with local autobone : assessment of bone fusion and subsidence.
abstract: OBJECTIVE
  It remains debatable whether cervical spine fusion cages should be filled with any kind of bone or bone substitute. Cortical and subcortical bone from the anterior and posterior osteophytes of the segment could be used to fill the cage. The purposes of the present study are to evaluate the clinical outcomes and radiological outcomes including bone fusion and subsidence that occurred after anterior cervical discectomy and fusion using a stand-alone cage packed with local autobone graft.
  
  
  METHODS
  Thirty-one patients who underwent anterior cervical fusion using a stand-alone polyetheretherketone (PEEK) cage packed with local autobone graft from July 2009 to december 2011 were enrolled in this study. Bone fusion was assessed by cervical plain radiographs and computed tomographic scan. Nonunion was evaluated according to the absence of bony bridge on computed tomographic scan. Subsidence was defined as a ≥2 mm decrease of the interbody height at the final follow-up compared to that measured at the immediate postoperative period.
  
  
  RESULTS
  Subsidence was observed in 7 patients (22.6%). Of 7 patients with subsidence greater 2 mm, nonunion was developed in 3. Three patients with subsidence greater 2 mm were related with endplate damage during intraoperative endplate preparation. Solid bone fusion was achieved in 28 out of 31 patients (90.3%).
  
  
  CONCLUSIONS
  With proper patient selection and careful endplate preparation, anterior cervical discectomy and fusion (ACDF) using a stand-alone PEEK cage packed with local autobone graft could be a good alternative to the standard ACDF techniques with plating.
authors.affiliation: Department of Neurosurgery, Kyungpook National University Hospital, Daegu, Korea.
authors.forename: Jeong-Ill
authors.initials: JI
authors.lastname: Park
authors.forename: Dae-Chul
authors.initials: DC
authors.lastname: Cho
authors.forename: Kyoung-Tae
authors.initials: KT
authors.lastname: Kim
authors.forename: Joo-Kyung
authors.initials: JK
authors.lastname: Sung
keywords: Cage; Cervical spine; Discectomy; Local bone