title: Clinical outcomes after high-flex versus conventional total knee arthroplasty.
abstract: OBJECTIVE
  To compare clinical outcomes after high-flex versus conventional total knee arthroplasty (TKA).
  
  
  METHODS
  A systematic review and meta-regression were performed to compare post-operative outcomes between the two types of prostheses. Relevant randomized controlled trials were identified from MEDLINE and Scopus up to November, 2014.
  
  
  RESULTS
  Fourteen of 369 studies were eligible; 14, 7, 6, 5, 3, 12 and 7 studies were included in the pooling of maximum knee flexion, Knee Society Knee Score (KS), Knee Society Function Score (FS), Hospital for Special Surgery score (HSS), short-form (SF) physical activity score, post-operative complications (DVT, fractures, infection) and revision TKA, respectively. The high-flex TKA had 1.97° [95% confidence interval (CI) 0.37, 3.57], -0.86 (95% CI -1.65, 0.07) and -1.34 (-2.57, -0.11) higher mean maximum knee flexion, KS and FS when compared to conventional TKA. However, there were non-significant differences in HSS, SF-36 (physical), complications and revision TKA.
  
  
  CONCLUSIONS
  This study suggests that there are improvements in post-operative knee range of motion and knee scores in high-flex TKA implants when compared to conventional TKA implants; however, the difference was very small and therefore might not have any clinical impact. Therefore, conventional TKA can be used as a substitute. However, cost-effective analysis should be performed to make appropriate selections in the future. There are no statistically significant differences in terms of HSS, quality of life, complications and revisions between the groups.
  
  
  METHODS
  I.
authors: Orthopedics Department, Police General Hospital, Bangkok, Thailand, amy.alisara@gmail.com.
authors: Alisara
authors: A
authors: Arirachakaran
authors: Tana
authors: T
authors: Wande
authors: Kwanchai
authors: K
authors: Pituckhanotai
authors: Pradit
authors: P
authors: Predeeprompan
authors: Jatupon
authors: J
authors: Kongtharvonskul
mesh_terms: D019645:Arthroplasty, Replacement, Knee / Q000295:instrumentation*; D006801:Humans; D007720:Knee Prosthesis; D011474:Prosthesis Design; D016059:Range of Motion, Articular