title: An anthropometric study of the distal humerus.
abstract: BACKGROUND
  The optimal articular shape for distal humeral hemiarthroplasty has not been defined because of a paucity of data quantifying the morphology of the normal distal humerus. This study defines the osseous anatomy and anatomic variability of the distal humerus using 3-dimensional imaging techniques.
  
  
  METHODS
  Three-dimensional surface models were created from computed tomography scans obtained from 50 unpaired human cadaveric elbows. Geometric centers of the capitellum and the trochlear groove defined the anatomic flexion-extension axis. A coordinate system was created, and the distal humerus was sectioned into 100 slices along this axis. The C line was defined as the line of best fit connecting the geometric centers of each of the slices.
  
  
  RESULTS
  The anatomic flexion-extension axis of the distal humerus was found to be an average of 1° ± 1° from the C line (range, 0°-3°) in the coronal plane and 2° ± 1° (range, 0°-7°) in the transverse plane. The average trochlear width was 22 ± 3 mm, and the average trochlear height was 18 ± 2 mm. The mean width of the capitellum was 17 ± 2 mm; the height was 23 ± 2 mm (P < .001).
  
  
  CONCLUSIONS
  The difference in the capitellum width and height demonstrates that the capitellum is ellipsoid, not spherical. A data bank of humeral dimensions may be used for the development of future distal humeral hemiarthroplasty implants. A more anatomic implant may optimize kinematics and maximize contact area, thus minimizing contact stresses on the native ulna and radius.
authors.affiliation: Department of Surgery, Western University, Roth | McFarlane Hand and Upper Limb Centre Bioengineering Laboratory, St. Joseph's Health Care, London, ON, Canada.
authors.forename: Sagar J
authors.initials: SJ
authors.lastname: Desai
authors.affiliation: Schulich School of Medicine & Dentistry, Western University, Roth | McFarlane Hand and Upper Limb Centre Bioengineering Laboratory, St. Joseph's Health Care, London, ON, Canada.
authors.forename: Simon
authors.initials: S
authors.lastname: Deluce
authors.affiliation: Department of Surgery, Department of Mechanical and Materials Engineering, Western University, Roth | McFarlane Hand and Upper Limb Centre Bioengineering Laboratory, St. Joseph's Health Care, London, ON, Canada.
authors.forename: James A
authors.initials: JA
authors.lastname: Johnson
authors.affiliation: Department of Surgery, Department of Mechanical and Materials Engineering, Western University, Roth | McFarlane Hand and Upper Limb Centre Bioengineering Laboratory, St. Joseph's Health Care, London, ON, Canada.
authors.forename: Louis M
authors.initials: LM
authors.lastname: Ferreira
authors.affiliation: Department of Surgery, Centre Hospitalier Université Laval, Québec, PQ, Canada.
authors.forename: Alexandre E
authors.initials: AE
authors.lastname: Leclerc
authors.affiliation: Department of Surgery, Western University, Roth | McFarlane Hand and Upper Limb Centre, St. Joseph's Health Care, London, ON, Canada.
authors.forename: George S
authors.initials: GS
authors.lastname: Athwal
authors.affiliation: Department of Surgery, Western University, Roth | McFarlane Hand and Upper Limb Centre, St. Joseph's Health Care, London, ON, Canada. Electronic address: gking@uwo.ca.
authors.forename: Graham J W
authors.initials: GJ
authors.lastname: King
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000886:Anthropometry; D002102:Cadaver; D004550:Elbow / Q000000981:diagnostic imaging / Q000601:surgery; D004551:Elbow Joint / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D006811:Humerus / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D014057:Tomography, X-Ray Computed
keywords: Distal humerus; elbow hemiarthroplasty; implant design; morphology