title: A Biomechanical Analysis of an Artificial Disc With a Shock-absorbing Core Property by Using Whole-cervical Spine Finite Element Analysis.
abstract: METHODS
  A biomechanical comparison among the intact C2 to C7 segments, the C5 to C6 segments implanted with fusion cage, and three different artificial disc replacements (ADRs) by finite element (FE) model creation reflecting the entire cervical spine below C2.
  
  
  OBJECTIVE
  The aim of this study was to analyze the biomechanical changes in subaxial cervical spine after ADR and to verify the efficacy of a new mobile core artificial disc Baguera C that is designed to absorb shock.
  
  
  BACKGROUND
  Scarce references could be found and compared regarding the cervical ADR devices' biomechanical differences that are consequently related to their different clinical results.
  
  
  METHODS
  One fusion device (CJ cage system, WINNOVA) and three different cervical artificial discs (Prodisc-C Nova (DePuy Synthes), Discocerv (Scient'x/Alphatec), Baguera C (Spineart)) were inserted at C5-6 disc space inside the FE model and analyzed. Hybrid loading conditions, under bending moments of 1 Nm along flexion, extension, lateral bending, and axial rotation with a compressive force of 50 N along the follower loading direction, were used in this study. Biomechanical behaviors such as segmental mobility, facet joint forces, and possible wear debris phenomenon inside the core were investigated.
  
  
  RESULTS
  The segmental motions as well as facet joint forces were exaggerated after ADR regardless of type of the devices. The Baguera C mimicked the intact cervical spine regarding the location of the center of rotation only during the flexion moment. It also showed a relatively wider distribution of the contact area and significantly lower contact pressure distribution on the core than the other two devices. A "lift off" phenomenon was noted for other two devices according to the specific loading condition.
  
  
  CONCLUSIONS
  The mobile core artificial disc Baguera C can be considered biomechanically superior to other devices by demonstrating no "lift off" phenomenon, and significantly lower contact pressure distribution on core.
  
  
  METHODS
  N/A.
authors.affiliation: Department of Neurosurgery, Kyung Hee University Medical Center, Seoul.
authors.forename: June Ho
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Mechanical Engineering, Kyung Hee University, Yongin.
authors.forename: Won Man
authors.initials: WM
authors.lastname: Park
authors.affiliation: Department of Mechanical Engineering, Kyung Hee University, Yongin.
authors.forename: Yoon Hyuk
authors.initials: YH
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, Spine Center, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea.
authors.forename: Tae-Ahn
authors.initials: TA
authors.lastname: Jahng
mesh_terms: D001696:Biomechanical Phenomena / Q000502:physiology; D002574:Cervical Vertebrae / Q000473:pathology / Q000601:surgery*; D020342:Finite Element Analysis; D006801:Humans; D007403:Intervertebral Disc / Q000473:pathology / Q000601:surgery*; D016059:Range of Motion, Articular / Q000502:physiology*; D059145:Total Disc Replacement / Q000379:methods; D021801:Zygapophyseal Joint / Q000473:pathology / Q000601:surgery*
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