title: Outcomes of cementless unicompartmental and total knee arthroplasty: A systematic review.
abstract: BACKGROUND
  Aseptic loosening is a common failure mode in cemented unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA). This led to the development of cementless designs but the historical outcomes were poor. Recent developments in cementless designs have improved outcomes, but the current status is unknown. Therefore, a systematic review was performed to assess recent outcomes of cementless knee arthroplasty.
  
  
  METHODS
  A search was performed using PubMed, Embase and Cochrane systems and national registries for studies reporting outcomes since 2005. Fifty-two cohort studies and four registries reported survivorship, failure modes or functional outcomes of cementless UKA and TKA.
  
  
  RESULTS
  Nine level I studies, six level II studies, three level III studies, 34 level IV studies and four registries were included. Three hundred eighteen failures in 10,309 cementless TKA procedures and 62 failures in 2218 cementless UKA procedures resulted in extrapolated five-year, 10-year and 15-year survivorship of cementless TKAs of 97.7%, 95.4% and 93.0%, respectively, and cementless UKA of 96.4%, 92.9% and 89.3%, respectively. Aseptic loosening was more common in cementless TKA (25%) when compared to UKA (13%). Functional outcomes of cementless TKA and UKA were excellent with 84.3% and 84.5% of the maximum possible scores, respectively.
  
  
  CONCLUSIONS
  This systematic review showed that good to excellent extrapolated survivorship and functional outcomes are seen following modern cementless UKA and TKA, with a low incidence of aseptic loosening following cementless UKA.
  
  
  METHODS
  Level IV.
authors.affiliation: Computer Assisted Surgery Center, Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Medical College of Cornell University, New York, NY, United States. Electronic address: vanderlistj@hss.edu.
authors.forename: Jelle P
authors.initials: JP
authors.lastname: van der List
authors.affiliation: Georgetown University School of Medicine, Washington, DC, United States. Electronic address: dana.sheng@gmail.com.
authors.forename: Dana L
authors.initials: DL
authors.lastname: Sheng
authors.affiliation: Computer Assisted Surgery Center, Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Medical College of Cornell University, New York, NY, United States. Electronic address: kleebladl@hss.edu.
authors.forename: Laura J
authors.initials: LJ
authors.lastname: Kleeblad
authors.affiliation: Computer Assisted Surgery Center, Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Medical College of Cornell University, New York, NY, United States. Electronic address: chawlah@hss.edu.
authors.forename: Harshvardhan
authors.initials: H
authors.lastname: Chawla
authors.affiliation: Computer Assisted Surgery Center, Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Medical College of Cornell University, New York, NY, United States. Electronic address: pearlea@hss.edu.
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Pearle
mesh_terms: D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D006801:Humans; D020370:Osteoarthritis, Knee / Q000601:surgery; D063868:Patient Outcome Assessment; D011475:Prosthesis Failure; D012086:Reoperation
keywords: Cementless; TKA; Total knee arthroplasty; UKA; Uncemented; Unicompartmental knee arthroplasty