title: Mid- to long-term outcomes of a medial-pivot system for primary total knee replacement: a systematic review and meta-analysis.
abstract: OBJECTIVE
  This systematic review and meta-analysis was conducted to determine the mid- to long-term clinical outcomes for a medial-pivot total knee replacement (TKR) system. The objectives were to synthesise available survivorship, Knee Society Scores (KSS), and reasons for revision for this system.
  
  
  METHODS
  A systematic search was conducted of two online databases to identify sources of survivorship, KSS, and reasons for revision. Survivorship results were compared with values in the National Joint Registry of England, Wales, and Northern Ireland (NJR).
  
  
  RESULTS
  A total of eight studies that included data for 1146 TKRs performed in six countries satisfied the inclusion/exclusion criteria. Pooled component survivorship estimates were 99.2% (95% CI, 97.7 to 99.7) and 97.6% (95% CI, 95.8 to 98.6) at five and eight years, respectively. Survivorship was similar or better when compared with rates reported for all cemented TKRs combined in the NJR and was significantly better than some insert types at mid-term intervals. The weighted mean post-operative KSS was 87.9 (73.2 to 94.2), in the excellent range. Similar cumulative revision rates and KSS were reported at centres in the United States, Europe, and Asia.
  
  
  CONCLUSIONS
  The subject system was associated with survivorship and KSS similar or better than that reported for other TKR systems. Cite this article: Bone Joint Res 2014;3:297-304.
authors.affiliation: MicroPort Orthopedics Inc., 5677 Airline Road, Arlington, Tennessee 38002, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: Fitch
authors.affiliation: MicroPort Orthopedics Inc., 5677 Airline Road, Arlington, Tennessee 38002, USA.
authors.forename: K
authors.initials: K
authors.lastname: Sedacki
authors.affiliation: MicroPort Orthopedics Inc., 5677 Airline Road, Arlington, Tennessee 38002, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Yang
keywords: Medial-pivot; Meta-analysis; Systematic review; Total knee arthroplasty