title: Prevalence of fat embolism after total knee arthroplasty performed with or without computer navigation.
abstract: BACKGROUND
  Total knee arthroplasty performed with computer-assisted navigation without breaching of the femoral medullary canal may decrease the prevalence of fat and/or bone-marrow-cell embolization. We performed this study to determine whether the use of navigation for primary total knee arthroplasty resulted in a different prevalence of fat and/or bone-marrow-cell embolization.
  
  
  METHODS
  We enrolled 160 patients (210 knees) who were scheduled to undergo primary total knee arthroplasty with navigation and 160 patients (210 knees) who were scheduled to undergo primary total knee arthroplasty without navigation. Arterial and right atrial blood samples were obtained before insertion of a femoral alignment rod or cutting of the distal part of the femur (baseline); at one, three, five, and ten minutes after insertion of an alignment rod or cutting of the distal part of the femur; before insertion of a tibial component broach (baseline); at one, three, five, and ten minutes after insertion of a tibial component broach; and at twenty-four and forty-eight hours after the operation. We determined the presence of fat emboli and bone-marrow-cell emboli in histologic preparations of the blood samples.
  
  
  RESULTS
  The prevalence of fat embolization was 49% (102 of 210 knees) in the total knee arthroplasty group managed with navigation and 52% (109 of 210 knees) in the total knee arthroplasty group managed without navigation (p = 0.2674). The prevalence of bone-marrow-cell embolization was 17% (thirty-six of 210 knees) in the group managed with navigation and 15% (thirty-one of 210 knees) in the group managed without navigation (p = 0.2591)
  
  
  CONCLUSIONS
  The prevalence of fat and/or bone-marrow-cell embolization was not significantly different between the patients who underwent total knee arthroplasty with navigation and those who underwent it without navigation.
authors.affiliation: The Joint Replacement Center of Korea, Ewha Womans University DongDaMun Hospital, 70, ChogRo 6-Ga, ChongRo-Gu, Seoul, South Korea. younghookim@ewha.ac.kr
authors.forename: Young-Hoo
authors.initials: YH
authors.lastname: Kim
authors.forename: Jun-Shik
authors.initials: JS
authors.lastname: Kim
authors.forename: Ki-Sook
authors.initials: KS
authors.lastname: Hong
authors.forename: Youn-Jin
authors.initials: YJ
authors.lastname: Kim
authors.forename: Jong-Hak
authors.initials: JH
authors.lastname: Kim
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects* / Q000379:methods; D004620:Embolism, Fat / Q000453:epidemiology* / Q000209:etiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000175:diagnosis* / Q000601:surgery*; D011183:Postoperative Complications; D015995:Prevalence; D011336:Probability; D011446:Prospective Studies; D012016:Reference Values; D018570:Risk Assessment; D012720:Severity of Illness Index; D025321:Surgery, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome