title: Can rotational alignment of total knee arthroplasty be measured on MRI?
abstract: OBJECTIVE
  The aim of this study was to investigate the potential of MRI to determine rotational alignment after TKA in comparison to the gold standard, CT.
  
  
  METHODS
  Rotational alignment was measured in the transverse plane on CT and MR-images in 14 patients prior to TKA revision. Differences between CT and MRI measurements were analysed.
  
  
  RESULTS
  There was a strong correlation between CT and MRI measurements for both the tibial (r = 0.929) and femoral (r = 0.942) components with a mean difference of 0.47 ± 1.3 and 0.13 ± 3.2 degrees, respectively.
  
  
  CONCLUSIONS
  Despite artefact formation, it can be concluded that the rotational alignment of metallic TKA components can be measured by MRI as accurately as by CT.
authors.affiliation: Department of Orthopaedics and Orthopaedic Surgery, University of Ulm, Oberer Eselsberg 45, 89081, Ulm, Germany. sgroi.mirco@yahoo.de.
authors.forename: Mirco
authors.initials: M
authors.lastname: Sgroi
authors.affiliation: Department of Orthopaedics and Orthopaedic Surgery, University of Ulm, Oberer Eselsberg 45, 89081, Ulm, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Faschingbauer
authors.affiliation: Department of Orthopaedics and Orthopaedic Surgery, University of Ulm, Oberer Eselsberg 45, 89081, Ulm, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Javaheripour-Otto
authors.affiliation: Department of Orthopaedics and Orthopaedic Surgery, University of Ulm, Oberer Eselsberg 45, 89081, Ulm, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Reichel
authors.affiliation: Department of Orthopaedics and Orthopaedic Surgery, University of Ulm, Oberer Eselsberg 45, 89081, Ulm, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Kappe
mesh_terms: D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000502:physiology / Q000503:physiopathology / Q000601:surgery; D008279:Magnetic Resonance Imaging; D016059:Range of Motion, Articular / Q000502:physiology*; D014057:Tomography, X-Ray Computed
keywords: AP Knee-recording; CT; MRI; Rotational alignment; Total knee arthroplasty