title: Does the severity of preoperative varus deformity influence postoperative alignment in both conventional and computer-assisted total knee arthroplasty?
abstract: OBJECTIVE
  The postoperative alignment was compared according to the severity of preoperative varus deformity in computer-assisted and conventional total knee arthroplasty (CAS-TKA).
  
  
  METHODS
  The study reviewed 127 consecutive CAS-TKA and 236 conventional TKA, retrospectively. In CAS-TKA, 77 knees with a varus deformity ≤15.0° were classified in group CAS-A and 50 knees with a varus deformity >15.0° were classified in group CAS-B. In conventional groups, 204 knees with a varus deformity ≤15.0 were classified in group Conventional-A and 32 knees with a varus deformity >15.0° were classified in group Conventional-B. The postoperative mechanical axis (MA) was compared among groups CAS-A, CAS-B, Conventional-A and Conventional-B.
  
  
  RESULTS
  The average postoperative MA was 0.7° varus in group CAS-A, 2.8° varus in group CAS-B, 1.1° varus in group Conventional-A and 3.2° varus in group Conventional-B (p < 0.001). The postoperative MA was within 3° in 81.8, 62.0, 58.8 and 37.5 % of group CAS-A, CAS-B, Conventional-A and Conventional-B, respectively.
  
  
  CONCLUSIONS
  The severity of preoperative varus deformity influences postoperative alignment despite using CAS. More careful correction of the alignment is required, especially in TKA performed on patients with a greater varus deformity.
  
  
  METHODS
  III.
authors.affiliation: Department of Orthopaedic Surgery, College of Medicine, Kyung Hee University, 26 Kyunghee-daero, Dongdaemun-gu, Seoul, 130-702, Korea.
authors.forename: Dae Kyung
authors.initials: DK
authors.lastname: Bae
authors.forename: Sang Jun
authors.initials: SJ
authors.lastname: Song
authors.forename: Dong Beom
authors.initials: DB
authors.lastname: Heo
authors.forename: Dae Hyun
authors.initials: DH
authors.lastname: Tak
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D060750:Bone Anteversion / Q000150:complications* / Q000000981:diagnostic imaging; D017760:Bone Malalignment / Q000000981:diagnostic imaging / Q000209:etiology* / Q000517:prevention & control; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D020370:Osteoarthritis, Knee / Q000150:complications / Q000601:surgery*; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000209:etiology* / Q000517:prevention & control; D057234:Preoperative Period; D011859:Radiography; D012189:Retrospective Studies; D012720:Severity of Illness Index; D025321:Surgery, Computer-Assisted; D016896:Treatment Outcome