title: Relationship between femoral component rotation and total knee flexion gap balance on modified axial radiographs.
abstract: Using modified axial radiographs, we investigated the relationship between femoral component rotation and flexion gap balance in 70 consecutive knees with varus osteoarthritis 1 year after they underwent cruciate-ligament-retaining total knee arthroplasty with the measured resection technique. We measured (1) the condylar twist angle, defined as the angle between the posterior condylar axis and the clinical epicondylar axis, and (2) the liftoff angle (LOA), defined as the angle between the posterior condylar axis and the tibial cutting surface. There was a significant positive correlation between the postoperative condylar twist angle (mean, 2.6°) and the postoperative LOA (mean, 1.8°). Our data suggest that a more accurate method of identifying the clinical epicondylar axis would lead to a smaller LOA as measured on modified axial radiographs.
authors.affiliation: Department of Orthopaedic Surgery, Social Insurance Gunma Central General Hospital, Maebashi, Gunma, 371-0025, Japan.
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Hatayama
authors.forename: Masanori
authors.initials: M
authors.lastname: Terauchi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Higuchi
authors.forename: Shinya
authors.initials: S
authors.lastname: Yanagisawa
authors.forename: Kenichi
authors.initials: K
authors.lastname: Saito
authors.forename: Kenji
authors.initials: K
authors.lastname: Takagishi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016118:Anterior Cruciate Ligament / Q000601:surgery; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D015331:Cohort Studies; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging* / Q000502:physiology*; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging* / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D016119:Posterior Cruciate Ligament / Q000601:surgery; D011184:Postoperative Period; D011446:Prospective Studies; D016059:Range of Motion, Articular / Q000502:physiology*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome