title: Legg-Calvé-Perthes disease: MR imaging evaluation during manual positioning of the hip--comparison with conventional arthrography.
abstract: OBJECTIVE
  To evaluate the use of magnetic resonance (MR) imaging during manual positioning of the hip, or multipositional MR imaging, in an open-magnet configuration to study femoral head containment, articular congruency, and femoral head deformity in Legg-Calvé-Perthes disease.
  
  
  METHODS
  In 12 children with advanced Legg-Calvé-Perthes disease, multipositional MR imaging and conventional arthrography were compared in the assessment of containment, femoroacetabular congruency, and femoral head deformity. Images of the hips in several positions were compared subjectively and objectively.
  
  
  RESULTS
  MR imging correlated well with arthrography for overall subjective assessment of severity of disease (r = 0.71, P = .01), with good interobserver agreement (kappa = 0.65, P < .001). MR images demonstrated all cases of hinge abduction shown arthrographically. However, MR imaging failed to depict one case of femoral head flattening. MR imaging correlated well with arthrography in the objective evaluation of joint fluid and lateral subluxation (r = 0.80, P < .01). MR imaging correlated poorly with arthrography in the measurement of sphericity of the femoral head.
  
  
  CONCLUSIONS
  Multipositional MR imaging with an open-magnet configuration was comparable to arthrography for demonstration of femoral head containment and congruency of the articular surfaces of the hip. In the evaluation of deformity, it performed less well.
authors.affiliation: Department of Radiology, Children's Hospital, Boston, MA 02115, USA. jaramillo@a1.tch.harvard.edu
authors.forename: D
authors.initials: D
authors.lastname: Jaramillo
authors.forename: T A
authors.initials: TA
authors.lastname: Galen
authors.forename: C S
authors.initials: CS
authors.lastname: Winalski
authors.forename: J
authors.initials: J
authors.lastname: DiCanzio
authors.forename: D
authors.initials: D
authors.lastname: Zurakowski
authors.forename: R V
authors.initials: RV
authors.lastname: Mulkern
authors.forename: P A
authors.initials: PA
authors.lastname: McDougall
authors.forename: O L
authors.initials: OL
authors.lastname: Villegas-Medina
authors.forename: F A
authors.initials: FA
authors.lastname: Jolesz
authors.forename: J R
authors.initials: JR
authors.lastname: Kasser
mesh_terms: D001175:Arthrography; D002648:Child; D005260:Female; D005270:Femur Head / Q000000981:diagnostic imaging / Q000473:pathology; D006621:Hip Joint / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D007873:Legg-Calve-Perthes Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging; D008279:Magnetic Resonance Imaging; D008297:Male; D011187:Posture