title: Computer-assisted total knee arthroplasty: impact of the surgeon's experience on the component placement.
abstract: BACKGROUND
  Accuracy of implant positioning in total knee arthroplasty (TKA) has a major impact on postoperative outcomes. We investigate the accuracy of positioning of multiples values simultaneously in TKA navigated, even among novice users.
  
  
  METHODS
  The "novice" group included the first 91 knees operated on by 10 operators new to navigation and the "experienced" group 174 knees by an experienced navigator. Deviations from the preoperative planning were graded as optimal (≤3°), acceptable (4°-5°) or non-acceptable (≥5°). Moreover, the percentage of the three values fulfilling simultaneously the objective was calculated.
  
  
  RESULTS
  No significant difference in the number of non-acceptable results was found. The common objective for these three values was achieved within 5° in 96 % in the novice group and 98 % in the experienced one.
  
  
  CONCLUSIONS
  The satisfactory HKA alignment was not the result of reversed errors between the tibia and the femur, since it correlated the successful simultaneous results of alpha and beta angles.
authors.affiliation: Department of Orthopedic Surgery, University of Reunion Island, Hospital of Saint-Pierre, BP 350, Saint Pierre Cedex, France. richardballas@yahoo.fr
authors.forename: Richard
authors.initials: R
authors.lastname: Ballas
authors.forename: Rémi
authors.initials: R
authors.lastname: Philippot
authors.forename: Jean-Loup
authors.initials: JL
authors.lastname: Cartier
authors.forename: Bertrand
authors.initials: B
authors.lastname: Boyer
authors.forename: Frédéric
authors.initials: F
authors.lastname: Farizon
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001168:Arthritis / Q000601:surgery*; D019645:Arthroplasty, Replacement, Knee / Q000379:methods / Q000592:standards* / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000601:surgery; D007720:Knee Prosthesis; D035002:Lower Extremity / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011859:Radiography; D013238:Stereotaxic Techniques; D025321:Surgery, Computer-Assisted