title: Within- and between-examiner repeatability of distraction indices of the hip joints in dogs.
abstract: OBJECTIVE
  To evaluate in vivo repeatability of the distraction index method of evaluating hip joint laxity in dogs.
  
  
  METHODS
  31 two-year-old Labrador Retrievers.
  
  
  METHODS
  Each dog was anesthetized and radiographically evaluated for hip joint laxity 4 times: twice by an experienced examiner and twice by an examiner who had no previous knowledge of or training in the technique prior to the first day of testing. Distraction indices (DI) were determined from the radiographs and intraclass correlation coefficients were calculated to evaluate the repeatability of DI measurements between and within examiners.
  
  
  RESULTS
  Intraclass correlation coefficients were high (range, 0.85 to 0.94). Lower limits of the 95% confidence intervals for the intraclass correlation coefficients ranged from 0.75 to 0.89.
  
  
  CONCLUSIONS
  Between- and within-examiner repeatabilities of DI measurements were high, suggesting that the technique is clinically reliable.
  
  
  CONCLUSIONS
  Distraction index is a reliable measure of hip joint laxity and a good predictor of the risk of development of degenerative joint disease associated with hip dysplasia in dogs. Establishment of high repeatability of DI measurements suggests that the stress-radiographic method may be used by multiple examiners with the expectation of comparable and consistent results.
authors.affiliation: Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia 19104, USA.
authors.forename: G K
authors.initials: GK
authors.lastname: Smith
authors.forename: E
authors.initials: E
authors.lastname: LaFond
authors.forename: T P
authors.initials: TP
authors.lastname: Gregor
authors.forename: D F
authors.initials: DF
authors.lastname: Lawler
authors.forename: R C
authors.initials: RC
authors.lastname: Nie
mesh_terms: D000077:Acetabulum / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology; D000818:Animals; D001696:Biomechanical Phenomena; D004285:Dogs / Q000033:anatomy & histology* / Q000502:physiology; D005270:Femur Head / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology; D006619:Hip Dysplasia, Canine / Q000453:epidemiology / Q000473:pathology / Q000503:physiopathology; D006621:Hip Joint / Q000033:anatomy & histology* / Q000502:physiology; D007593:Joint Instability / Q000175:diagnosis / Q000662:veterinary*; D015588:Observer Variation; D011237:Predictive Value of Tests; D011859:Radiography / Q000379:methods / Q000662:veterinary; D015203:Reproducibility of Results; D012307:Risk Factors; D016474:Weight-Bearing / Q000502:physiology