title: CT evaluation of extra-articular glenoid neck fractures: does the glenoid medialize or does the scapula lateralize?
abstract: OBJECTIVE
  Medial translation of the glenoid is frequently described as the main mode of displacement after glenoid neck fracture. Indeed, plain radiographs typically show the glenoid medialized relative to the scapular body. However, whether this truly represents medialization of the glenoid relative to the axial skeleton or lateralization of the scapular body remains unclear. The goal of this investigation was to assess the relationship between the glenoid, the scapular body, and the axial skeleton in patients with glenoid neck fractures using computed tomographic data analysis with the contralateral shoulder serving as an internal control.
  
  
  METHODS
  Retrospective radiographic review.
  
  
  METHODS
  Two Level I trauma centers.
  
  
  METHODS
  Eighteen patients (5 women and 13 men; average age, 38.7 years; range, 17-75 years) admitted between January 2000 and March 2006 with isolated extra-articular glenoid neck fractures (OTA 14C1 fractures) and chest computed tomographic scans that included both shoulders.
  
  
  METHODS
  Glenoid to midline distance and scapular width.
  
  
  RESULTS
  The injured glenoid was lateralized an average of 9.8 mm (range, 8 mm medialized to 23 mm lateralized) (P < 0.001). Relative to the uninjured side, glenoid medialization infrequently occurred (4 of 18 patients) and when present was less than 1 cm (range, 2-8 mm). Lateralization occurred more frequently (14 of 18 patients), with an average displacement of 13.7 mm (range, 1-23 mm). The injured scapula was shortened by an average of 3.3 mm (range, 18 mm shorter to 20 mm longer) (P = 0.09). In 15 of 18 patients, the scapular width was shortened by an average of 5.9 mm (range, 1-18 mm), whereas in only 3 of 18 patients was the injured scapular width longer, an average of 9 mm (range, 1-20 mm).
  
  
  CONCLUSIONS
  In patients with glenoid neck fractures, pure medial translation of the glenoid relative to the axial skeleton rarely occurs. Instead, there is typically a component of shortening of the scapula width combined with lateralization of the scapular body.
authors.affiliation: Department of Orthopaedics, University of North Carolina School of Medicine, Chapel Hill, NC, USA.
authors.forename: Jennifer Megan M
authors.initials: JM
authors.lastname: Patterson
authors.forename: Leesa
authors.initials: L
authors.lastname: Galatz
authors.forename: Philipp N
authors.initials: PN
authors.lastname: Streubel
authors.forename: Jared
authors.initials: J
authors.lastname: Toman
authors.forename: Paul
authors.initials: P
authors.lastname: Tornetta
authors.forename: William M
authors.initials: WM
authors.lastname: Ricci
mesh_terms: D000063:Accidents, Traffic; D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D005593:Fracture Fixation, Internal; D050723:Fractures, Bone / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D061165:Glenoid Cavity / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012540:Scapula / Q000000981:diagnostic imaging / Q000293:injuries / Q000473:pathology* / Q000601:surgery; D012785:Shoulder Joint; D014057:Tomography, X-Ray Computed; D055815:Young Adult