title: Comparison of Operating Time between Stand-alone Cage and a Standard Method for a Single Level Cervical Disc Disease.
abstract: OBJECTIVE
  Autologous bone graft with anterior plating had been a standard method for anterior cervical discectomy and fusion (ACDF). Drawbacks of a standard method were donor site problem and problem associated with anterior plate. The stand-alone cage was introduced to reduce such problems. However, problems associated with subsidence and local kyphosis at the index level (segmental kyphosis) still persist with stand-alone cage and a standard method would be required in some cases. It seems that harvest of autologous bone and anterior plating procedure is time consuming, but this has not been verified. The aim of this study was to compare the operating time between patients operated on with stand-alone cage versus a standard method for single-level cervical disc disease.
  
  
  METHODS
  Consecutive 29 patients (M:F=18:11; mean age, 58.4±12.4 years), who had undergone ACDF for single-level disc disease by a single surgeon from incision to closure during 2009-2011, were selected for this retrospective study. Seventeen patients were operated with stand-alone cage (Group I), and twelve patients were with a standard method (Group II). Operating time (from incision to closure), estimated blood loss, clinical and radiological outcomes were compared. Follow-up period was 11.4±6.3 months.
  
  
  RESULTS
  Operating time was not different between groups longer; Group I (96.1±28.7 minutes) and Group II (112.4±31.7 minutes) (p=0.13). There was no surgery related complication. Excellent or good outcome was achieved in 11 and 10 patients of group I and II, respectively. Bony fusion was achieved in 15 and 10 patients of group I and II respectively, while one subsidence occurred in each group. Postoperative segmental angle at the index level and cervical curvature was not different between groups. No patient complained donor site pain at the last follow-up.
  
  
  CONCLUSIONS
  ACDF with a standard method for single-level cervical disc disease was not a time-consuming procedure comparing stand-alone cage.
authors.affiliation: Department of Neurosurgery, Seoul National University College of Medicine; Neuroscience Research Institute, Seoul National University Medical Research Center; Clinical Research Institute, Seoul National University Hospital, Seoul, Korea.
authors.forename: Chang Hyoun
authors.initials: CH
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, Seoul National University College of Medicine; Neuroscience Research Institute, Seoul National University Medical Research Center; Clinical Research Institute, Seoul National University Hospital, Seoul, Korea.
authors.forename: Chi Heon
authors.initials: CH
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, Seoul National University College of Medicine; Neuroscience Research Institute, Seoul National University Medical Research Center; Clinical Research Institute, Seoul National University Hospital, Seoul, Korea.
authors.forename: Chun Kee
authors.initials: CK
authors.lastname: Chung
authors.affiliation: Department of Neurosurgery, Seoul National University College of Medicine; Neuroscience Research Institute, Seoul National University Medical Research Center; Clinical Research Institute, Seoul National University Hospital, Seoul, Korea.
authors.forename: Tae-Ahn
authors.initials: TA
authors.lastname: Jahng
keywords: Cage; Cervical; Discectomy; Plate; Spine; Standard