title: The hundred most-cited publications in orthopaedic knee research.
abstract: BACKGROUND
  Despite its limitations, citation analysis remains one of the best currently available tools for quantifying the impact of articles. Bibliometric studies list the "best-sellers" in a single location, and they have been published frequently in many fields during recent years. The purpose of the present study was to report the qualities and characteristics of citation classics in orthopaedic knee research.
  
  
  METHODS
  The database of the Institute for Scientific Information (ISI) was utilized for identification of articles published from 1945 to March 2014. All knee articles that had been published in sixty-five orthopaedic and twenty-nine rheumatology journals and that had been cited at least 200 times were identified. The top 100 were selected for further analysis of authorship, source journal, number of citations, citation rate (both since publication and in 2013), geographic origin, article type, and level of evidence.
  
  
  RESULTS
  The publication dates of the 100 most-cited articles ranged from 1948 to 2007, with the greatest number of articles published in the 1980s. Citations per article ranged from 2640 to 287. All articles were published in eleven of the ninety-four journals. The leading countries of origin were the U.S. followed by the U.K. and Sweden. The two main focus areas were sports traumatology and degenerative disease. The number of citations per article was also greatest for articles published in the 1980s. Basic research articles were cited more quickly, but not more often, than clinical articles. Most articles represented Level-IV evidence, followed by Levels II, III, and I.
  
  
  CONCLUSIONS
  This bibliometric study is likely to include a list of intellectual milestones in orthopaedic knee research. It is apparent that a high level of evidence is not mandatory for an article to gain a large number of citations. Bibliometric reports provide a reflection of the quality of cited research published in a specific field and should therefore provoke thinking within the scientific community.
authors.affiliation: Department of Orthopedic Surgery and Traumatology, Inselspital, University of Bern, Freiburgstrasse, 3010 Bern, Switzerland. E-mail address for S.S. Ahmad: sufian.ahmad@insel.ch.
authors.forename: Sufian S
authors.initials: SS
authors.lastname: Ahmad
authors.affiliation: Department of Orthopedic Surgery and Traumatology, Inselspital, University of Bern, Freiburgstrasse, 3010 Bern, Switzerland. E-mail address for S.S. Ahmad: sufian.ahmad@insel.ch.
authors.forename: Dimitrios S
authors.initials: DS
authors.lastname: Evangelopoulos
authors.affiliation: Department of Orthopedic Surgery and Traumatology, Inselspital, University of Bern, Freiburgstrasse, 3010 Bern, Switzerland. E-mail address for S.S. Ahmad: sufian.ahmad@insel.ch.
authors.forename: M
authors.initials: M
authors.lastname: Abbasian
authors.affiliation: Institute for Evaluative Research in Medicine, University of Bern, Stauffacherstrasse, 3007 Bern, Switzerland.
authors.forename: Christoph
authors.initials: C
authors.lastname: Röder
authors.affiliation: Department of Orthopedic Surgery and Traumatology, Inselspital, University of Bern, Freiburgstrasse, 3010 Bern, Switzerland. E-mail address for S.S. Ahmad: sufian.ahmad@insel.ch.
authors.forename: Sandro
authors.initials: S
authors.lastname: Kohl
mesh_terms: D015706:Bibliometrics; D006801:Humans; D009985:Orthopedics; D020370:Osteoarthritis, Knee / Q000601:surgery*; D012219:Rheumatology; D014194:Traumatology