title: Comparative study of clinical and radiological outcomes of a zero-profile device concerning reduced postoperative Dysphagia after single level anterior cervical discectomy and fusion.
abstract: OBJECTIVE
  This study analyzed clinical and radiological outcomes of a zero-profile anchored spacer (Zero-P) and conventional cage-plate (CCP) for single level anterior cervical discectomy and fusion (ACDF) to compare the incidence and difference of postoperative dysphagia with both devices.
  
  
  METHODS
  We retrospectively reviewed our experiences of single level ACDF with the CCP and Zero-P. From January 2011 to December 2013, 48 patients who had single level herniated intervertebral disc were operated on using ACDF, with CCP in 27 patients and Zero-P in 21 patients. Patients who received more than double-level ACDF or combined circumferential fusion were excluded. Age, operation time, estimated blood loss (EBL), pre-operative modified Japanese Orthopaedic Association (mJOA) scores, post-operative mJOA scores, achieved mJOA scores and recovery rate of mJOA scores were assessed. Prevertebral soft tissue thickness and postoperative dysphagia were analyzed on the day of surgery, and 2 weeks and 6 months postoperatively.
  
  
  RESULTS
  The Zero-P group showed same or favorable clinical and radiological outcomes compared with the CCP group. Postoperative dysphagia was significantly low in the Zero-P group.
  
  
  CONCLUSIONS
  Application of Zero-P may achieve favorable outcomes and reduce postoperative dysphagia in single level ACDF.
authors.affiliation: Department of Neurosurgery, Pusan National University Yangsan Hospital, Yangsan, Korea.
authors.forename: Doo Kyung
authors.initials: DK
authors.lastname: Son
authors.affiliation: Department of Neurosurgery, Pusan National University Yangsan Hospital, Yangsan, Korea.
authors.forename: Dong Wuk
authors.initials: DW
authors.lastname: Son
authors.affiliation: Department of Neurosurgery, Maryknoll Hospital, Busan, Korea.
authors.forename: Ho Sang
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, Pusan National University Yangsan Hospital, Yangsan, Korea.
authors.forename: Soon Ki
authors.initials: SK
authors.lastname: Sung
authors.affiliation: Department of Neurosurgery, Pusan National University Yangsan Hospital, Yangsan, Korea.
authors.forename: Sang Weon
authors.initials: SW
authors.lastname: Lee
authors.affiliation: Department of Neurosurgery, Pusan National University Yangsan Hospital, Yangsan, Korea.
authors.forename: Geun Sung
authors.initials: GS
authors.lastname: Song
keywords: ACDF; Anterior cervical discectomy and fusion; Dysphagia; Prevertebral soft tissue swelling; Zero-profile