title: How much articular displacement can be detected using fluoroscopy for tibial plateau fractures?
abstract: BACKGROUND
  While there is conflicting evidence regarding the importance of anatomic reduction for tibial plateau fractures, there are currently no studies that analyse our ability to grade reduction based on fluoroscopic imaging. The purpose of this study was to determine the accuracy of fluoroscopy in judging tibial plateau articular reduction.
  
  
  METHODS
  Ten embalmed human cadavers were selected. The lateral plateau was sagitally sectioned, and the joint was reduced under direct visualization. Lateral, anterior-posterior (AP), and joint line fluoroscopic views were obtained. The same fluoroscopic views were obtained with 2mm displacement and 5mm displacement. The images were randomised, and eight orthopaedic traumatologists were asked whether the plateau was reduced. Within each pair of conditions (view and displacement from 0mm to 5mm) sensitivity, specificity, and intraclass correlations (ICC) were evaluated.
  
  
  RESULTS
  The AP-lateral view with 5mm displacement yielded the highest accuracy for detecting reduction at 90% (95% CI: 83-94%). For the other conditions, accuracy ranged from (37-83%). Sensitivity was highest for the reduced lateral view (79%, 95% CI: 57-91%). Specificity was highest in the AP-lateral view 98% (95% CI: 93-99%) for 5mm step-off. ICC was perfect for the AP-lateral view with 5mm displacement, but otherwise agreement ranged from poor to moderate at ICC=0.09-0.46. Finally, there was no additional benefit to including the joint-line view with the AP and lateral views.
  
  
  CONCLUSIONS
  Using both AP and lateral views for 5mm displacement had the highest accuracy, specificity, and ICC. Outside of this scenario, agreement was poor to moderate and accuracy was low. Applying this clinically, direct visualization of the articular surface may be necessary to ensure malreduction less than 5mm.
authors.affiliation: Department of Orthopaedic Surgery, University of Utah, 590 Wakara Way, Salt Lake City, UT 84108, United States. Electronic address: Justin.haller@hsc.utah.edu.
authors.forename: Justin M
authors.initials: JM
authors.lastname: Haller
authors.affiliation: R Adams Cowley Shock Trauma Center, Department of Orthopaedic Surgery, University of Maryland School of Medicine, 22 S Greene Street, Baltimore, MD 21201, United States. Electronic address: rvo3@yahoo.com.
authors.forename: Robert
authors.initials: R
authors.lastname: O'Toole
authors.affiliation: Department of Orthopaedic Surgery and Rehabilitation, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS 39216, United States. Electronic address: mattgraves1@gmail.com.
authors.forename: Matthew
authors.initials: M
authors.lastname: Graves
authors.affiliation: Department of Orthopaedic Surgery, Harborview Medical Center, 325 9th Avenue, Seattle, WA 98014, United States. Electronic address: barei@uw.edu.
authors.forename: David
authors.initials: D
authors.lastname: Barei
authors.affiliation: Department of Orthopaedic Surgery, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, United States. Electronic address: gardnerm@wudosis.wustl.edu.
authors.forename: Michael
authors.initials: M
authors.lastname: Gardner
authors.affiliation: Department of Orthopaedic Surgery, University of Utah, 590 Wakara Way, Salt Lake City, UT 84108, United States. Electronic address: erik.kubiak@hsc.utah.edu.
authors.forename: Erik
authors.initials: E
authors.lastname: Kubiak
authors.affiliation: R Adams Cowley Shock Trauma Center, Department of Orthopaedic Surgery, University of Maryland School of Medicine, 22 S Greene Street, Baltimore, MD 21201, United States. Electronic address: Jnascone@umoa.umm.edu.
authors.forename: Jason
authors.initials: J
authors.lastname: Nascone
authors.affiliation: Department of Orthopaedic Surgery, Harborview Medical Center, 325 9th Avenue, Seattle, WA 98014, United States. Electronic address: nork@uw.edu.
authors.forename: Sean
authors.initials: S
authors.lastname: Nork
authors.affiliation: Department of Orthopaedic Surgery, University of Utah, 590 Wakara Way, Salt Lake City, UT 84108, United States; Division of Epidemiology, Department of Internal Medicine, University of Utah, Salt Lake City, UT, United States. Electronic address: angela.presson@hsc.utah.edu.
authors.forename: Angela P
authors.initials: AP
authors.lastname: Presson
authors.affiliation: Department of Orthopaedic Surgery, University of Utah, 590 Wakara Way, Salt Lake City, UT 84108, United States. Electronic address: thomas.higgins@hsc.utah.edu.
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Higgins
mesh_terms: D000328:Adult; D000368:Aged; D002102:Cadaver; D005260:Female; D005471:Fluoroscopy / Q000379:methods; D005593:Fracture Fixation, Internal / Q000379:methods; D006801:Humans; D004204:Joint Dislocations / Q000000981:diagnostic imaging*; D007719:Knee Joint / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013978:Tibial Fractures / Q000000981:diagnostic imaging*
keywords: Anatomic reduction; Articular fracture; Malreduction; Proximal tibia fracture; Reduction