title: A Comparison of Plain Radiographs and Computed Tomography for Determining Canal Diameter of the Distal Phalanx.
abstract: OBJECTIVE
  To compare plain radiographs and computed tomography (CT) when determining the narrowest diameter of the medullary canal of the distal phalanx.
  
  
  METHODS
  A database review identified 48 patients (23 male, 25 female) who underwent a CT scan of the hand and plain radiographs of the same hand. Using digital imaging software, the smallest diameter of the medullary canal was measured for each finger (index, middle, ring, little) on CT and on radiographs.
  
  
  RESULTS
  The narrowest diameter of the medullary canal was measured on the axial CT and lateral hand radiograph at the transition between the tuft and the distal phalanx shaft. The mean narrowest diameters on plain radiographs for the index, middle, ring, and little fingers were 1.4 mm, 1.4 mm, 1.4 mm, and 1.1 mm, respectively. The mean diameters on CT were 1.2 mm, 1.3 mm, 1.2 mm, and 1.0 mm, respectively. Men had larger medullary canal dimensions (1.5-1.7 mm) than women (0.8-1.2 mm).
  
  
  CONCLUSIONS
  The differences in canal diameter measurements between plain radiograph and CT were small and likely clinically insignificant.
  
  
  CONCLUSIONS
  Lateral radiographs can be used for preoperative planning when estimating the size of the distal phalanx intramedullary canal.
authors.affiliation: Department of Orthopaedics, University of Pittsburgh School of Medicine, Pittsburgh, PA.
authors.forename: William L
authors.initials: WL
authors.lastname: Wang
authors.affiliation: Department of Radiology, University of Pittsburgh, Pittsburgh, PA.
authors.forename: Maxine
authors.initials: M
authors.lastname: Darke
authors.affiliation: Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Goitz
authors.affiliation: Department of Radiology, University of Pittsburgh, Pittsburgh, PA.
authors.forename: Carol L
authors.initials: CL
authors.lastname: Andrews
authors.affiliation: Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA. Electronic address: johnfowler10@gmail.com.
authors.forename: John R
authors.initials: JR
authors.lastname: Fowler
mesh_terms: D000328:Adult; D059925:Anatomic Landmarks; D005260:Female; D050278:Finger Phalanges / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D011857:Radiographic Image Interpretation, Computer-Assisted; D014057:Tomography, X-Ray Computed
keywords: CT; Canal; distal; medullary; phalanx