title: Three dimensional morphologic analysis of the lateral surface of the canine femur.
abstract: OBJECTIVE
  Analyze the lateral plating surface of the femur to obtain bend and twist angles in dogs with non-chondrodystrophic phenotype.
  
  
  METHODS
  Retrospective computed tomography (CT) morphologic analysis.
  
  
  METHODS
  Historical cohort, hindlimb CT scans (n = 30).
  
  
  METHODS
  The CT images of 30 normal femurs were uploaded to surgical planning software and 13 points of interest and their respective bend/twist angles were identified on the lateral surfaces. Mean, standard deviation, coefficient of variation (CV), and range were calculated for each bend/twist angle. Hierarchal clustering and fast Fourier Analyses were used to segment the cohort. Distribution of age, breed, sex, and weight was evaluated between clusters with an exact Wilcoxon-Mann-Whitney test.
  
  
  RESULTS
  The CV of bending ranged from 17% to 46% and for twisting ranged from 21% to 58%. The greater trochanter was the most pronounced bend on the lateral surface of the femur (mean ± SD 8.11 ± 1.35°, CV 17%), and the supracondylar region of the distal femur was the most marked twist (mean ± SD 48.98 ± 10.06°, CV 21%). Although there were no differences between dogs in proximal femur anatomy, 2 clusters of 9 and 21 dogs each were identified due to differences in bend/twist angles in the distal femur. There was no difference between clusters for age (P = .85), breed (P = .62), and sex (P = .15); however, weight differed (P = .03) but was not predictive.
  
  
  CONCLUSIONS
  Although distal femoral lateral surfaces varied sufficiently to result in 2 population clusters, further analysis is needed to determine if the differences prevent using the mean bending and twisting parameters as a template for clinical applications.
authors: Department of Veterinary Clinical Medicine, Veterinary Teaching Hospital, University of Illinois, Urbana, Illinois.
authors: Helia
authors: H
authors: Zamprogno
authors: Nathan
authors: N
authors: Nelson
authors: David J
authors: DJ
authors: Schaeffer
authors: Ann L
authors: AL
authors: Johnson
mesh_terms: D000818:Animals; D001947:Breeding; D004285:Dogs / Q000033:anatomy & histology*; D005260:Female; D005269:Femur / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D006614:Hindlimb / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D006621:Hip Joint / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D008297:Male; D011187:Posture; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000662:veterinary