title: Interobserver repeatability of measurements on computed tomography images of lax canine hip joints from youth to maturity.
abstract: OBJECTIVE
  To determine interobserver repeatability of measurements on computed tomography (CT) images of lax canine hip joints at different ages and in the presence of degenerative joint disease at maturity.
  
  
  METHODS
  Longitudinal observational investigation.
  
  
  METHODS
  Sibling crossbreed hounds.
  
  
  METHODS
  Pelvic CT was performed at 20, 24, 32, 48, 68, and 104 weeks of age. Measures were performed on 3 contiguous two-dimensional (2D) transverse CT images of both hips at each time point by 3 investigators. Center-edge angle (CEA), horizontal toit externe angle (HTEA), ventral (VASA), dorsal (DASA), and horizontal (HASA) acetabular sector angles, acetabular index (AI), and percent femoral head coverage (CPC) were measured. Interobserver repeatability was quantified with the intraclass correlation coefficient (ICC). Satisfactory repeatability was considered when ICC >or=0.75.
  
  
  RESULTS
  DASA, CEA, and CPC were repeatable in all age groups. HASA and HTEA were repeatable for all but 1 time point. At 20 weeks of age, all measures but AI were repeatable, and at 104 weeks of age, DASA, CEA, CPC, and HASA were repeatable. Measures were repeatable in hips with and without degenerative changes with the exceptions of AI and HASA in normal hips and VASA and HTEA in osteoarthritic hips.
  
  
  CONCLUSIONS
  Most 2D CT measurements examined were repeatable regardless of age or joint disease.
  
  
  CONCLUSIONS
  Two-dimensional CT measures may augment current techniques for assessing joint changes in lax canine hips.
authors.affiliation: Laboratory for Equine and Comparative Orthopedic Research, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA. mlopez@vetmed.lsu.edu
authors.forename: Mandi J
authors.initials: MJ
authors.lastname: Lopez
authors.forename: Kechia M
authors.initials: KM
authors.lastname: Davis
authors.forename: Susan L
authors.initials: SL
authors.lastname: Jeffrey-Borger
authors.forename: Mark D
authors.initials: MD
authors.lastname: Markel
authors.forename: Christy
authors.initials: C
authors.lastname: Rettenmund
mesh_terms: D000367:Age Factors; D000818:Animals; D004285:Dogs; D005260:Female; D006619:Hip Dysplasia, Canine / Q000000981:diagnostic imaging*; D006621:Hip Joint / Q000000981:diagnostic imaging; D008137:Longitudinal Studies; D008297:Male; D015588:Observer Variation; D010003:Osteoarthritis / Q000000981:diagnostic imaging / Q000662:veterinary; D014057:Tomography, X-Ray Computed / Q000662:veterinary