title: Mid-term outcomes of computer-assisted total knee arthroplasty.
abstract: OBJECTIVE
  The aim of this study is to investigate the clinical results of total knee arthroplasty (TKA) using a navigation system after a minimum of 5 years.
  
  
  METHODS
  Thirty cases of posterior-stabilized, TKA-implanted using a computed tomography-free navigation system were compared with 30 cases having matched TKA of the same type implanted via a classical, manual technique. At mid term, a minimum of 5 years after surgery, Knee Society scores (KSSs), Knee Society Functional scores (KSFSs), range of motion (ROM), and radiographic results of 27 patients in each group were assessed and reported in this study.
  
  
  RESULTS
  The accuracy of the implantations in relation to the coronal mechanical axis in the navigation group was superior to that of the manual group (P < 0.01). The femoral rotational profile revealed the prosthesis in the navigation group that was implanted with significantly less internal rotation than the manual group. Mid-term 5-year clinical results, including ROMs and KSSs, were significantly better in the navigation group (P < 0.01). KSFSs were equally good in both the groups.
  
  
  CONCLUSIONS
  Better alignment and similarity of good clinical results at mid-term follow up may provide patients who receive navigation TKA with long-term endurance of their implants. Further studies on longer-term outcomes and functional improvements are required to validate these possibilities.
authors.affiliation: Department of Orthopaedic Surgery, Hyogo Rehabilitation Centre Center Hospital, 1070 Akebono-cho, Nishi-ku, Kobe 651-2181, Japan. wavedreamer17@yahoo.co.jp
authors.forename: Kazunari
authors.initials: K
authors.lastname: Ishida
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Matsumoto
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Tsumura
authors.forename: Seiji
authors.initials: S
authors.lastname: Kubo
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kitagawa
authors.forename: Takaaki
authors.initials: T
authors.lastname: Chin
authors.forename: Tetsuhiro
authors.initials: T
authors.lastname: Iguchi
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kurosaka
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Kuroda
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D016022:Case-Control Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D025321:Surgery, Computer-Assisted; D016896:Treatment Outcome