title: Delays to initial reduction attempt are associated with higher failure rates in anterior shoulder dislocation: a retrospective analysis of factors affecting reduction failure.
abstract: BACKGROUND
  Little is understood about the relationship between delay to treatment and initial reduction success for anterior shoulder dislocation. Our study examines whether delays to initial treatment, from injury and hospital presentation, are associated with higher reduction failure rates for anterior shoulder dislocation.
  
  
  METHODS
  A retrospective database and chart review was performed for patients undergoing intravenous sedation for attempted reduction of anterior shoulder dislocation in the emergency department (ED). Stepwise regression analysis was performed to identify predictors of reduction failure. Key variables analysed were the duration of the wait in the ED, the interval between the time of injury and first intervention and the interval from time of injury to arrival at the ED. Possible confounding variables analysed included age, gender, dose of sedative agent, qualifications of the reducing physician and whether the dislocated shoulder was recurrent.
  
  
  RESULTS
  The duration of the intervals from injury to first reduction attempt and from arrival at the ED to first reduction attempt were both independent predictors of a higher reduction failure rate (OR=1.07, 95% CI 1.02 to 1.13; OR=1.19, 95% CI 1.05 to 1.34). Every interval of 10 min increased the odds of a failed reduction attempt by 7% and 19%, respectively. Overall, shoulder reduction was successful during the initial sedation event in 97 cases (92%) and unsuccessful in nine cases (8%).
  
  
  CONCLUSIONS
  Delays to first reduction attempt either from the time of injury or within the ED are associated with a lower reduction success rate for anterior shoulder dislocations.
authors.affiliation: Faculty of Medicine, University College Cork, Cork, Ireland Department of Emergency Medicine, Horizon Health Network, Saint John, New Brunswick, Canada.
authors.forename: Avinash
authors.initials: A
authors.lastname: Kanji
authors.affiliation: Department of Emergency Medicine, Horizon Health Network, Saint John, New Brunswick, Canada Department of Emergency Medicine, Dalhousie University, Saint John, New Brunswick, Canada Discipline of Emergency Medicine, Memorial University, Saint John, New Brunswick, Canada New Brunswick Trauma Program, Saint John Regional Hospital, Saint John, New Brunswick, Canada.
authors.forename: Paul
authors.identifier: http://orcid.org/0000-0001-9900-4594
authors.initials: P
authors.lastname: Atkinson
authors.affiliation: Department of Emergency Medicine, Dalhousie University, Saint John, New Brunswick, Canada Discipline of Emergency Medicine, Memorial University, Saint John, New Brunswick, Canada.
authors.forename: Jacqueline
authors.identifier: http://orcid.org/0000-0002-6267-4620
authors.initials: J
authors.lastname: Fraser
authors.affiliation: Department of Emergency Medicine, Horizon Health Network, Saint John, New Brunswick, Canada Department of Emergency Medicine, Dalhousie University, Saint John, New Brunswick, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Lewis
authors.affiliation: Department of Emergency Medicine, Horizon Health Network, Saint John, New Brunswick, Canada New Brunswick Trauma Program, Saint John Regional Hospital, Saint John, New Brunswick, Canada.
authors.forename: Susan
authors.initials: S
authors.lastname: Benjamin
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage; D008297:Male; D008349:Manipulation, Orthopedic; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D012783:Shoulder Dislocation / Q000628:therapy*; D013997:Time Factors; D017211:Treatment Failure
chemical_list: D006993:Hypnotics and Sedatives
keywords: Trauma, extremity; musculo-skeletal, fractures and dislocations; triage