title: Analysis of pelvic rotation on the standard hip ventrodorsal extended radiographic view.
abstract: OBJECTIVE
  To study the symmetry of the iliac horizontal diameter (IHD) maximum obturator foramen width (OFW), ischiatic femoral overlap (IFO), pelvic horizontal radius (PHR), femoral head diameter (FHD), and obturator foramen area (OFA) parameters in the normal hip extended radiographic view and to evaluate the correlation of pelvic rotation with the magnitude of asymmetry of these parameters.
  
  
  METHODS
  Nine canine cadavers from adult, large and giant breeds were radiographed in standard hip extended views and with 2°, 4° and 6° degrees of rotation. The variables IHD, OFW, IFO, PHR, FHD, and OFA were analysed in radiographs.
  
  
  RESULTS
  The IHD measurements exhibited repeatability, bilateral symmetry and 95% of confidence interval of asymmetry in different pelvic rotations without superposition (p <0.05); OFW and IFO exhibited repeatability, bilateral symmetry and a small superposition in 95% of confidence interval of asymmetry according different pelvic rotations; PHR, FHD and OFA exhibited repeatability, bilateral symmetry and unacceptable superposition in 95% of confidence interval of asymmetry depending on pelvic rotation.
  
  
  CONCLUSIONS
  The IHD is the recommended variable and OFW is an acceptable variable in order to evaluate slight pelvic rotation. The data may be used in qualitative analyses of hip extended radiographic views. In the future, complementary studies should be performed to evaluate the impact of degree of pelvic rotation on the hip dysplasia score.
authors.affiliation: João MC Martins, DVM, MVS, Centre for Research and Technology of Agro-Environment and Biological Sciences, University of Trás-os-Montes e Alto Douro, 5001-801 Vila Real, Portugal, Phone: + 351 962693208, E-mail: ccarlamartins@sapo.pt.
authors.forename: João
authors.initials: J
authors.lastname: Martins
authors.forename: Bruno J
authors.initials: BJ
authors.lastname: Colaço
authors.forename: António J
authors.initials: AJ
authors.lastname: Ferreira
authors.forename: Mário M
authors.initials: MM
authors.lastname: Ginja
mesh_terms: D000818:Animals; D004285:Dogs; D005270:Femur Head / Q000000981:diagnostic imaging; D006619:Hip Dysplasia, Canine / Q000000981:diagnostic imaging*; D010388:Pelvis / Q000000981:diagnostic imaging*; D011859:Radiography; D012399:Rotation
keywords: Iliac horizontal diameter; femoral head diameter; femoral overlap; ischiatic overlap; maximum obturator foramen width; obturator foramen area; pelvic horizontal radius