title: Factors predicting the development of early osteoarthritis following lateral tibial plateau fractures: mid-term clinical and radiographic outcomes of 73 operatively treated patients.
abstract: OBJECTIVE
  The indications for operative treatment of lateral tibial plateau fractures are still controversial. The objective of this study was to determine whether residual articular surface depression and valgus malalignment of plated lateral tibial plateau fractures at medium-term follow-up affect the clinical and radiographic outcomes.
  
  
  METHODS
  A chart review of patients with operatively treated (AO type B3.1) tibial plateau fractures that were admitted to our level I trauma center between 2002 and 2008 was performed. Out of 123 patients, 73 were available to participate in a clinical and radiographic follow-up examination. The mean follow-up time was 54 months. Patients were clinically assessed and completed the Lysholm knee score and Western Ontario and McMaster Universities Osteoarthritis Index. Maximal articular surface depression, radiological mechanical axis, and degree of posttraumatic osteoarthritis were evaluated from standing radiographs.
  
  
  RESULTS
  Patients with valgus malalignment of 5° or greater at follow-up developed more advanced osteoarthritis (Kellgren-Lawrence grade 3-4) than patients with a normal mechanical axis (p = 0.006). Similarly, patients with articular depression greater than 2 mm at follow-up also developed more advanced osteoarthritis compared to patients with a depression of 2 mm or less (p = 0.001). The degree of valgus malalignment or articular depression had no effect on the Western Ontario and McMaster Universities Osteoarthritis Index or Lysholm scores.
  
  
  CONCLUSIONS
  The postoperative articular congruity and normal mechanical axis of the lower leg after plate fixation in lateral tibial plateau fractures seem to have a role in prevention of posttraumatic osteoarthritis but does not appear to predict clinical outcome at medium-term follow-up. The role of initial dislocation and associated cartilage damage in the development of osteoarthritis following these fractures is still unknown.
authors.affiliation: Department of Orthopaedics and Traumatology, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland markus.parkkinen@hus.fi.
authors.forename: M
authors.initials: M
authors.lastname: Parkkinen
authors.affiliation: Department of Orthopaedics and Traumatology, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: R
authors.initials: R
authors.lastname: Madanat
authors.affiliation: Department of Radiology, University of Helsinki and HUS Radiology (Medical Imaging Center), Helsinki, Finland.
authors.forename: A
authors.initials: A
authors.lastname: Mustonen
authors.affiliation: Department of Radiology, University of Helsinki and HUS Radiology (Medical Imaging Center), Helsinki, Finland.
authors.forename: S K
authors.initials: SK
authors.lastname: Koskinen
authors.affiliation: Department of Orthopaedics and Traumatology, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: M
authors.initials: M
authors.lastname: Paavola
authors.affiliation: Department of Orthopaedics and Traumatology, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: J
authors.initials: J
authors.lastname: Lindahl
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D005387:Finland / Q000453:epidemiology; D005500:Follow-Up Studies; D005593:Fracture Fixation, Internal; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000209:etiology*; D011379:Prognosis; D011859:Radiography; D016059:Range of Motion, Articular; D012189:Retrospective Studies; D012307:Risk Factors; D013978:Tibial Fractures / Q000150:complications* / Q000000981:diagnostic imaging / Q000601:surgery; D013997:Time Factors; D055815:Young Adult
keywords: Tibial plateau; clinical outcome; fracture; internal fixation; lateral condyle; radiographic outcome