title: Perioperative Risk Assessment in Patients Aged 75 Years or Older: Comparison between Bilateral and Unilateral Total Knee Arthroplasty.
abstract: OBJECTIVE
  The purpose of this study is to evaluate the risk of sequential bilateral total knee arthroplasty (TKA) under 1 anesthesia in patients 75 years or older.
  
  
  METHODS
  Patients aged 75 years or older who underwent sequential bilateral TKA (bilateral group, n=159) and unilateral TKA (unilateral group, n=159) between 2002 and 2012 were selected. All patients were evaluated for underlying medical diseases, such as cardiac, pulmonary, and renal problems, and high-risk patients were recommended to postpone the surgery. We compared the underlying diseases, major postoperative complications, and the length of hospital stay between bilateral and unilateral groups.
  
  
  RESULTS
  The prevalence of underlying diseases of the bilateral group was 74.8% and major complications occurred in 6 patients (3.8%). The prevalence of underlying diseases of the unilateral group was 52.4% and complications were observed in 4 patients (2.4%). Although the complication rate of the bilateral group was slightly higher than that of the unilateral group, the difference was not statistically meaningful (p=0.204). The length of hospital stay was 21.9 days for the bilateral group and 24.9 days for the unilateral group.
  
  
  CONCLUSIONS
  There was no significant difference in postoperative complications between groups. The result shows that bilateral TKA can be relatively safe compared with unilateral TKA in patients 75 years or older. However, careful selection of low-risk patients is advised.
authors.affiliation: Department of Orthopaedic Surgery, Gangneung Asan Hospital, Ulsan University College of Medicine, Gangneung, Korea.
authors.forename: Young-Joon
authors.initials: YJ
authors.lastname: Choi
authors.affiliation: Department of Orthopaedic Surgery, Gangneung Asan Hospital, Ulsan University College of Medicine, Gangneung, Korea.
authors.forename: Hyun-Il
authors.initials: HI
authors.lastname: Lee
authors.affiliation: Department of Orthopaedic Surgery, Gangneung Asan Hospital, Ulsan University College of Medicine, Gangneung, Korea.
authors.forename: Ho Jong
authors.initials: HJ
authors.lastname: Ra
authors.affiliation: Department of Orthopaedic Surgery, Gangneung Asan Hospital, Ulsan University College of Medicine, Gangneung, Korea.
authors.forename: Do-Yon
authors.initials: DY
authors.lastname: Hwang
authors.affiliation: Department of Orthopaedic Surgery, Gangneung Asan Hospital, Ulsan University College of Medicine, Gangneung, Korea.
authors.forename: Tae-Kyung
authors.initials: TK
authors.lastname: Kim
authors.affiliation: Department of Orthopaedic Surgery, Gangneung Asan Hospital, Ulsan University College of Medicine, Gangneung, Korea.
authors.forename: Sang-Jun
authors.initials: SJ
authors.lastname: Shim
keywords: Aged patients; Arthroplasty; Knee; Postoperative complications