title: Proximal humerus fracture with injury to the axillary artery: a population-based study.
abstract: BACKGROUND
  The available evidence regarding axillary artery injury as a result of proximal humerus fracture consists of individual case reports or small series. This study used nationally representative data to determine the prevalence and predictors of axillary artery injury secondary to proximal humerus fracture, and to characterise its influence on inpatient mortality, length of stay, cost and discharge disposition.
  
  
  METHODS
  An estimated 388,676 inpatients with a proximal humerus fracture were identified in the Nationwide Inpatient Sample between 2002 and 2011, 331 with concomitant axillary artery injury (8.5 per 10,000). Multivariable regression modelling was used to identify independent predictors of axillary artery injury and to assess its relationship with inpatient outcomes.
  
  
  RESULTS
  Factors associated with axillary artery injury were male sex (odds ratio (OR): 1.6, 95% confidence interval (CI): 1.2-2.0), atherosclerosis (OR: 3.7, 95% CI: 2.5-5.4), open fracture (OR: 2.9, 95% CI: 1.9-4.5) and the presence of concomitant injuries, including brachial plexus injury (OR: 109, 95% CI: 79-151), shoulder dislocation (OR: 3.4, 95% CI: 2.0-5.8), scapula fracture (OR: 3.4, 95% CI: 2.1-5.4) and rib fracture (OR: 2.5, 95% CI: 1.6-4.0). Axillary artery injury was associated with increased length of stay, costs and mortality, but it did not affect discharge disposition.
  
  
  CONCLUSIONS
  Our study provides important baseline information regarding the epidemiology of axillary artery injury secondary to proximal humerus fracture. Prompt identification of at-risk patients upon admission might lead to improved diagnosis and management of this vascular injury.
  
  
  METHODS
  Prognostic level II.
authors.affiliation: Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Mariano E
authors.initials: ME
authors.lastname: Menendez
authors.affiliation: Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA. Electronic address: dring@partners.org.
authors.forename: David
authors.initials: D
authors.lastname: Ring
authors.affiliation: Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Marilyn
authors.initials: M
authors.lastname: Heng
mesh_terms: D000368:Aged; D001366:Axillary Artery / Q000000981:diagnostic imaging / Q000293:injuries*; D003324:Coronary Artery Disease / Q000150:complications* / Q000453:epidemiology; D005260:Female; D005597:Fractures, Open / Q000150:complications* / Q000000981:diagnostic imaging / Q000453:epidemiology; D017052:Hospital Mortality; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D015995:Prevalence; D011379:Prognosis; D011859:Radiography; D012189:Retrospective Studies; D012307:Risk Factors; D017678:Sex Distribution; D012784:Shoulder Fractures / Q000150:complications* / Q000000981:diagnostic imaging / Q000453:epidemiology; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology; D057772:Vascular System Injuries / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000209:etiology*
keywords: Axillary artery injury; Epidemiology; Outcomes; Prevalence; Proximal humerus fracture; Vascular injury