title: Current state of the art in total knee arthroplasty computer navigation.
abstract: OBJECTIVE
  Computer-assisted surgery in orthopaedics is passing through the initial adapter phase of technology adoption. It started more than 20 years ago, but the uptake of technology is still not widespread. The purpose of this article is to introduce the reader to the basic technology and familiarize with the terminology used in the computer navigation.
  
  
  METHODS
  During this time, the technology has matured and we have the evidence to prove its benefits for patients. Not only does it help placing the prosthetic components in correct orientation, it also helps with other parameters like blood loss and fat embolism reduction. In addition to being a teaching and training tool, it has also opened new areas of research which now question the traditional practices. Since it is not in commonly used, the basic aspects of computer navigation are not very well known.
  
  
  RESULTS
  This paper outlines some important definitions and restates the classification of navigation within the spectrum of computer-assisted technologies; it then elaborates on the key principles behind navigation in knee arthroplasty and goes through some of the differences between navigation systems. Finally, it describes in some detail the surgical steps with an image-free knee navigation system.
  
  
  CONCLUSIONS
  Computer-assisted navigation is not mainstream yet, but this article should help readers unfamiliar with the technology to understand the basic terms and how it actually works.
  
  
  METHODS
  III.
authors.affiliation: Department of Orthopaedics, Golden Jubilee National Hospital, Agamemnon Street, Glasgow, G81 4DY, UK. fredjm_picard@yahoo.com.
authors.forename: Frederic
authors.initials: F
authors.lastname: Picard
authors.affiliation: Department of Orthopaedics, Golden Jubilee National Hospital, Agamemnon Street, Glasgow, G81 4DY, UK.
authors.forename: Kamal
authors.identifier: http://orcid.org/0000-0002-2268-9940
authors.initials: K
authors.lastname: Deep
authors.affiliation: Hôpitaux Universitaires de Strasbourg, CCOM, 10 avenue Baumann, 67400, Illkirch, France.
authors.forename: Jean Yves
authors.initials: JY
authors.lastname: Jenny
mesh_terms: D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D006801:Humans; D021621:Imaging, Three-Dimensional; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D019637:Orthopedic Procedures; D025321:Surgery, Computer-Assisted / Q000379:methods*; D014057:Tomography, X-Ray Computed
keywords: Computer; Computer-assisted surgery; Image-based; Image-free; Knee replacement; Navigation; Registration