title: [Reproducibility of radiologic diagnosis in gonarthrosis].
abstract: OBJECTIVE
  Ongoing efforts of the "German Society of Orthopaedic Surgery and Traumatology" (DGOT) to standardize diagnosis and therapy of osteoarthritis, necessitated this study, where the reproducibility of different radiographic features of knee-OA was assessed.
  
  
  METHODS
  Three readers graded 100 antero-posterior and lateral knee radiographs for selected features (femorotibial osteophytes, joint space narrowing, sclerosis and chondrocalcinosis; patellofemoral osteophytes) and an overall-score (Kellgren and Lawrence, 1963) at two time points 3 months apart. Intra- and inter-observer-reliability were calculated by intra-class correlation-coefficient (ICC).
  
  
  RESULTS
  Osteophytes in the femorotibial as well as in the patellofemoral joint could be assessed with a high intra- and inter-observer-reliability. While for joint space narrowing intra-observer-reliability is excellent, the inter-observer-reliability is less satisfactory, and subchondral sclerosis as well as chondrocalcinosis showed even less reproducibility. The Kellgren-Lawrence global score proofed to be highly reproducible.
  
  
  CONCLUSIONS
  Based on the results of this examination, we can recommend a reliable radiographic classification of knee osteoarthritis by grading of relevant individual features (osteophytes and joint space narrowing) and overall assessment.
authors.affiliation: Orthopädische Abteilung des RKU, Orthopädische Klinik mit Querschnittgelähmtenzentrum der Universität Ulm.
authors.forename: K P
authors.initials: KP
authors.lastname: Günther
authors.forename: H P
authors.initials: HP
authors.lastname: Scharf
authors.forename: W
authors.initials: W
authors.lastname: Puhl
authors.forename: W
authors.initials: W
authors.lastname: Willauschus
authors.forename: Y
authors.initials: Y
authors.lastname: Kalke
authors.forename: K
authors.initials: K
authors.lastname: Glückert
authors.forename: Y
authors.initials: Y
authors.lastname: Sun
mesh_terms: D005500:Follow-Up Studies; D006621:Hip Joint / Q000000981:diagnostic imaging*; D006801:Humans; D015588:Observer Variation; D010003:Osteoarthritis / Q000145:classification / Q000000981:diagnostic imaging* / Q000534:rehabilitation; D011859:Radiography; D015203:Reproducibility of Results