title: The Fate of Adjacent Segments After Anterior Cervical Discectomy and Fusion: The Influence of an Anterior Plate System.
abstract: OBJECTIVE
  The purpose of this study was to compare anterior cervical discectomy and fusion with cage alone (ACDF-CA) and anterior cervical discectomy and fusion with cage and plate (ACDF-CP) with regard to adjacent segment degeneration (ASD) diagnosed by the use of CT and MRI with retrospective matched cohort design.
  
  
  METHODS
  This study enrolled 68 patients who underwent single-level ACDF who were diagnosed with cervical degenerative disc disease and were followed up for at least 2 years with plain radiographs, computed tomography, and magnetic resonance imaging. The patients were divided into 2 groups according to the operation method: ACDF-CA (33 patients) and ACDF-CP (35 patients).
  
  
  RESULTS
  ASD occurred in 4 of 33 patients who underwent ACDF-CA and 9 of 35 patients who underwent ACDF-CP as determined by computed tomography and magnetic resonance imaging. The upper segment range of motion and lower segment range of motion increased in both groups postoperatively. The increase was greater in the ACDF-CP group without statistical significance. The upper segment disc height and lower segment disc height gradually decreased in both groups over time. The decrease was significantly greater in the ACDF-CP group at each follow-up visit. Pseudarthrosis and cage subsidence was observed more in the ACDF-CA group. The pain intensity for the neck in the ACDF-CA group was increased 12 and 24 months postoperatively.
  
  
  CONCLUSIONS
  The anterior plate system in ACDF tends to increase adjacent segmental motion and decrease adjacent segmental disc height. In addition, irrespective of clinical symptoms, ACDF-CP has a greater tendency to result in ASD than ACDF-CA after 24 months after surgery.
authors.affiliation: Department of Neurosurgery, Spine and Spinal Cord Institute, Gangnam Severance Spine Hospital, Yonsei University College of Medicine, Seoul, Korea. Electronic address: ahnsangsoak@hanmail.net.
authors.forename: Sang-Soak
authors.initials: SS
authors.lastname: Ahn
authors.affiliation: Department of Neurosurgery, Spine and Spinal Cord Institute, Gangnam Severance Spine Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Ho-Kyu
authors.initials: HK
authors.lastname: Paik
authors.affiliation: Department of Neurosurgery, Spine and Spinal Cord Institute, Gangnam Severance Spine Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Dong-Kyu
authors.initials: DK
authors.lastname: Chin
authors.affiliation: Department of Radiology, Dong-A University Medical Center, Busan, Korea.
authors.forename: Sang-Hyeon
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of Radiology, Dong-A University Medical Center, Busan, Korea.
authors.forename: Dong-Won
authors.initials: DW
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, 21 Century Hospital, Jeju, Korea.
authors.forename: Min-Geun
authors.initials: MG
authors.lastname: Ku
mesh_terms: D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D017586:Diskectomy / Q000295:instrumentation* / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016268:Internal Fixators; D055959:Intervertebral Disc Degeneration / Q000000981:diagnostic imaging / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012086:Reoperation; D012189:Retrospective Studies; D013123:Spinal Fusion / Q000295:instrumentation* / Q000379:methods; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
keywords: Adjacent segment; Cervical vertebrae; Degeneration; Discectomy; Fusion; Plate