title: Computed tomographic evaluation of elbow congruity during arthroscopy in a canine cadaveric model.
abstract: OBJECTIVE
  To assess the effect of arthroscope insertion, using a carbon-fibre rod model, on humero-radial, humero-ulnar and radio-ulnar congruity, as assessed by computed tomography (CT).
  
  
  METHODS
  Cadaveric Greyhound elbow joints were assessed at a flexion angle of 135 ± 5° using CT. For condition 1, a 36 mm fulcrum induced cubital valgus, as used to aid arthroscope insertion. For conditions 2 and 3, a single 1.8 or 2.5 mm diameter rod was inserted under arthroscopic guidance to simulate arthroscope position for assessment of the medial coronoid process. Repeat CT scans were obtained for all conditions and parasagittal sections were reconstructed to evaluate medial, axial and lateral positions within the elbow. Humero-radial, humero-ulnar, and radio-ulnar congruity measurements were obtained. Differences between groups were assessed using repeated measures analysis of variance.
  
  
  RESULTS
  Mean (±SD) change in radio-ulnar step between conditions 1 and 3 was 0.6 ± 0.3 mm (axial), 0.8 ± 0.6 mm (medial), and 0.5 ± 0.1 mm (lateral). Insertion of rods induced a significant decrease in radio-ulnar step in all planes. Significant differences were also identified between groups for humero-radial, humero-ulnar, and radio-ulnar congruity.
  
  
  CONCLUSIONS
  Insertion of carbon-fibre rods as a model for elbow arthroscope insertion induces elbow incongruity. Changes in radio-ulnar congruity are small but the effect of arthroscope diameter should be considered when assessing elbow congruity.
authors.forename: O T
authors.initials: OT
authors.lastname: Skinner
authors.forename: C M R
authors.initials: CM
authors.lastname: Warren-Smith
authors.forename: N J
authors.initials: NJ
authors.lastname: Burton
authors.affiliation: Kevin J. Parsons, Department of Clinical Veterinary Sciences, University of Bristol, Langford House, Langford, Bristol, BS40 5DU, United Kingdom, Phone: +44 1179 289420, Fax: +44 1179 289628, E-mail: kevin.parsons@bristol.ac.uk.
authors.forename: K J
authors.initials: KJ
authors.lastname: Parsons
mesh_terms: D000818:Animals; D001175:Arthrography / Q000662:veterinary; D001182:Arthroscopy / Q000662:veterinary*; D004285:Dogs / Q000033:anatomy & histology*; D005552:Forelimb / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D006811:Humerus / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D007596:Joints / Q000033:anatomy & histology*; D014057:Tomography, X-Ray Computed / Q000662:veterinary; D014457:Ulna / Q000033:anatomy & histology / Q000000981:diagnostic imaging
keywords: Elbow; arthroscopy; computed tomography; congruity; dog