title: Distribution of coronoid fracture lines by specific patterns of traumatic elbow instability.
abstract: OBJECTIVE
  To determine if specific coronoid fractures relate to specific overall traumatic elbow instability injury patterns and to depict any relationship on fracture maps and heat maps.
  
  
  METHODS
  We collected 110 computed tomography (CT) studies from patients with coronoid fractures. Fracture types and pattern of injury were characterized based on anteroposterior and lateral radiographs, 2- and 3-dimensional CT scans, and intraoperative findings as described in operative reports. Using quantitative 3-dimensional CT techniques we were able to reconstruct the coronoid and reduce fracture fragments. Based on these reconstructions, fracture lines were identified and graphically superimposed onto a standard template in order to create 2-dimensional fracture maps. To further emphasize the fracture maps, the initial diagrams were converted into fracture heat maps following arbitrary units of measure. The Fisher exact test was used to evaluate the association between coronoid fracture types and elbow fracture-dislocation patterns.
  
  
  RESULTS
  Forty-seven coronoid fractures were associated with a terrible triad fracture dislocation, 30 with a varus posteromedial rotational injury, 1 with a anterior olecranon fracture dislocation, 22 with a posterior olecranon fracture dislocation, and 7 with a posterior Monteggia injury associated with terrible triad fracture dislocation of the elbow. The association between coronoid fracture types and elbow fracture-dislocation patterns, as shown on 2-dimensional fracture and heat maps, was strongly significant.
  
  
  CONCLUSIONS
  Our fracture maps and heat maps support the observation that specific patterns of traumatic elbow instability have correspondingly specific coronoid fracture patterns. Knowledge of these patterns is useful for planning management because it directs exposure and fixation and helps identify associated ligament injuries and fractures that might benefit from treatment.
  
  
  CONCLUSIONS
  Two-dimensional fracture and heat mapping techniques may help surgeons to predict the distribution of coronoid fracture lines associated with specific injury patterns.
authors: Orthopaedic Hand and Upper Extremity Service, Massachusetts General Hospital, Boston, MA; Department of Orthopaedic Surgery, Brigham and Women's Hospital, Boston, MA; Orthotrauma Research Center Amsterdam, Academic Medical Center, Amsterdam, The Netherlands.
authors: Jos J
authors: JJ
authors: Mellema
authors: Orthopaedic Hand and Upper Extremity Service, Massachusetts General Hospital, Boston, MA; Department of Orthopaedic Surgery, Brigham and Women's Hospital, Boston, MA; Orthotrauma Research Center Amsterdam, Academic Medical Center, Amsterdam, The Netherlands.
authors: Job N
authors: JN
authors: Doornberg
authors: Orthopaedic Hand and Upper Extremity Service, Massachusetts General Hospital, Boston, MA; Department of Orthopaedic Surgery, Brigham and Women's Hospital, Boston, MA; Orthotrauma Research Center Amsterdam, Academic Medical Center, Amsterdam, The Netherlands.
authors: George S M
authors: GS
authors: Dyer
authors: Orthopaedic Hand and Upper Extremity Service, Massachusetts General Hospital, Boston, MA; Department of Orthopaedic Surgery, Brigham and Women's Hospital, Boston, MA; Orthotrauma Research Center Amsterdam, Academic Medical Center, Amsterdam, The Netherlands. Electronic address: dring@partners.org.
authors: David
authors: D
authors: Ring
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004551:Elbow Joint / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D007593:Joint Instability / Q000145:classification / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D014458:Ulna Fractures / Q000145:classification / Q000000981:diagnostic imaging*; D055815:Young Adult; D000092464:Elbow Injuries
keywords: Coronoid; elbow; fractures; injury; mapping