title: A Comparison of the Medium-Term Results of Total Knee Arthroplasty Using Computer-Assisted and Conventional Techniques to Treat Patients With Extraarticular Femoral Deformities.
abstract: We compared the medium-term results of total knee arthroplasty (TKA) performed using computer-assisted surgery (CAS) and conventional techniques in patients with extraarticular femoral deformities.
  
  
  
  The clinical and radiographic data of 40 knees (34 patients) with extraarticular femoral deformities that underwent consecutive CAS-TKA were compared with those of a control group that underwent conventional TKA (80 knees, 63 patients). No demographic data (in particular, the causes of the extraarticular deformities) differed between the two groups. The follow-up periods of the CAS and conventional TKA groups were 6.0 and 6.3 years, respectively.
  
  
  
  In the CAS group, the average knee score increased from 48.2 to 89.6 at the final follow-up (P < .001); the average function score increased from 51.4 to 91.4. The range of motion averaged 105.5° preoperatively and 123.3° postoperatively. No significant differences were found in the knee score, function score, or range of motion after TKA between the 2 groups. The average preoperative mechanical axes were 18.1° varus in both groups. The average postoperative mechanical axis was 1.4° varus in the CAS group and 3.3° varus in the conventional TKA group (P = .001). The proportion of postoperatively aligned knees was 77.5% in the CAS group and 32.5% in the conventional group (P < .001).
  
  
  
  Although the medium-term clinical results of TKA in extraarticular femoral deformities were satisfactory in both the CAS and conventional TKA groups, the former group exhibited more accurate postoperative coronal alignment. It was useful to employ navigation in patients with extraarticular deformities of various etiologies.
authors.affiliation: Department of Orthopaedic Surgery, College of Medicine, Kyung Hee University, Seoul, Korea.
authors.forename: Dae Kyung
authors.initials: DK
authors.lastname: Bae
authors.affiliation: Department of Orthopaedic Surgery, College of Medicine, Kyung Hee University, Seoul, Korea.
authors.forename: Sang Jun
authors.initials: SJ
authors.lastname: Song
authors.affiliation: Department of Orthopaedic Surgery, College of Medicine, Kyung Hee University, Seoul, Korea.
authors.forename: Cheol Hee
authors.initials: CH
authors.lastname: Park
authors.affiliation: Department of Orthopaedic Surgery, College of Medicine, Kyung Hee University, Seoul, Korea.
authors.forename: Young Wan
authors.initials: YW
authors.lastname: Ko
authors.affiliation: Department of Orthopaedic Surgery, College of Medicine, Kyung Hee University, Seoul, Korea.
authors.forename: Hojin
authors.initials: H
authors.lastname: Lee
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D005260:Female; D005264:Femoral Fractures / Q000601:surgery; D005269:Femur / Q000002:abnormalities* / Q000601:surgery; D005500:Follow-Up Studies; D006801:Humans; D007719:Knee Joint / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D011859:Radiography; D016059:Range of Motion, Articular; D012189:Retrospective Studies; D025321:Surgery, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome
keywords: arthroplasty; computer-assisted technique; conventional technique; extraarticular deformity; knee