title: Computed navigated total knee arthroplasty compared to computed tomography scans.
abstract: BACKGROUND
  Successful total knee arthroplasty (TKA) includes accurate alignment. Controversy remains as to whether computer-navigated TKA improves the overall result and clinical outcome. Our aim is to compare the limb alignment and prosthesis positioning according to the pre- and postoperative computed tomography (CT) scans with the data collected from the navigation system.
  
  
  METHODS
  We compared the pre- and postoperative limb alignments and prosthesis alignment provided by the Orthopilot navigation system, Aesculap®, with CT scans measured by the Traumacad® software of 70 TKAs.
  
  
  RESULTS
  A positive correlation with statistical significance (P=0.00001, r=0.874) between the navigation system data and the CT images was found. Mean femoral cut was five degrees (valgus), and mean tibial cut was one degree (varus). Our study revealed that the navigation system assisted the surgeon to implant the prosthesis at a good acceptable alignment.
  
  
  CONCLUSIONS
  We found that the navigation system is accurate and correlates to the pre- and postoperative CT scans. Furthermore, the navigation system can assist the surgeon to achieve good limb alignment and cutting planes of the prosthesis.
authors.affiliation: Faculty of Medicine, Bar-Ilan, Zeffat, Israel.
authors.forename: Ron
authors.initials: R
authors.lastname: Batash
authors.affiliation: Orthopedic Department, Emek Medical Center, Afula, Israel; Faculty of Medicine, Technion, Haifa, Israel.
authors.forename: Guy
authors.initials: G
authors.lastname: Rubin
authors.affiliation: Faculty of Medicine, Bar-Ilan, Zeffat, Israel; Orthopedic Department, Ziv Medical Center, Zefat, Israel.
authors.forename: Alexander
authors.initials: A
authors.lastname: Lerner
authors.affiliation: Orthopedic Department, Ziv Medical Center, Zefat, Israel.
authors.forename: Hussein
authors.initials: H
authors.lastname: Shehade
authors.affiliation: Orthopedic Department, Emek Medical Center, Afula, Israel; Faculty of Medicine, Technion, Haifa, Israel.
authors.forename: Nimrod
authors.initials: N
authors.lastname: Rozen
authors.affiliation: Faculty of Medicine, Bar-Ilan, Zeffat, Israel; Orthopedic Department, Ziv Medical Center, Zefat, Israel. Electronic address: david.r@ziv.health.gov.il.
authors.forename: David E
authors.initials: DE
authors.lastname: Rothem
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging* / Q000601:surgery*; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D025321:Surgery, Computer-Assisted; D014057:Tomography, X-Ray Computed
keywords: Computed tomography; Navigation; Total knee arthroplasty