title: The impact of trauma-center care on mortality and function following pelvic ring and acetabular injuries.
abstract: BACKGROUND
  Lower mortality and improved physical function following major polytrauma have been associated with treatment at level-I trauma centers compared with that at hospitals without a trauma center (nontrauma centers). This study investigated the impact of trauma-center care on outcomes after pelvic and acetabular injuries.
  
  
  METHODS
  Mortality and quality-of-life-related scores were compared among patients treated in eighteen level-I trauma centers and fifty-one nontrauma centers in fourteen U.S. states. Complete data were obtained on 829 adult trauma patients (eighteen to eighty-four years old) who had at least one pelvic ring or acetabular injury (Orthopaedic Trauma Association [OTA] classification of 61 or 62). We used inverse probability of treatment weighting to adjust for observable confounding.
  
  
  RESULTS
  After adjusting for case mix, we found that, for patients with more severe acetabular injuries (OTA 62-B or 62-C), in-hospital mortality was significantly lower at trauma centers compared with nontrauma centers (relative risk [RR], 0.10; 95% confidence interval [CI], 0.02 to 0.47), as was death within ninety days (RR, 0.10; 95% CI, 0.02 to 0.47) and within one year (RR, 0.21; 95% CI, 0.06 to 0.76). Patients with combined pelvic ring and acetabular injuries treated at a trauma center had lower mortality at ninety days (RR, 0.34; 95% CI, 0.14 to 0.82) and at one year (RR, 0.30; 95% CI, 0.14 to 0.68). Care at trauma centers was also associated with mortality risk reduction for those with unstable pelvic ring injuries (OTA 61-B or 61-C) at one year (RR, 0.71; 95% CI, 0.24 to 0.91). Seventy-eight percent of included subjects discharged alive were available for interview at twelve months. For those with more severe acetabular injuries, average absolute differences in the Short Form-36 (SF-36) physical function component and the Musculoskeletal Function Assessment at one year were 11.4 (95% CI, 5.3 to 17.4) and 13.2 (1.7 to 24.7), respectively, indicating statistically and clinically significant improved outcomes following treatment at a trauma center for those patients.
  
  
  CONCLUSIONS
  Mortality was reduced for patients with unstable pelvic and severe acetabular injuries when care was provided in a trauma center compared with a nontrauma center. Moreover, those with severe acetabular fractures experienced improved physical function at one year. Patients with these injuries represent a well-defined subset of trauma patients for whom our findings suggest preferential triage or transfer to a level-I trauma center.
authors.affiliation: Orthopaedic Trauma Institute, Departments of Orthopaedic Surgery and of Epidemiology and Biostatistics, University of California, San Francisco and San Francisco General Hospital, 2550 23rd Street, Building 9, 2nd Floor, San Francisco, CA 94110. E-mail address for S. Morshed: morsheds@orthosurg.ucsf.edu.
authors.forename: Saam
authors.initials: S
authors.lastname: Morshed
authors.affiliation: Orthopaedic Trauma Institute, Departments of Orthopaedic Surgery and of Epidemiology and Biostatistics, University of California, San Francisco and San Francisco General Hospital, 2550 23rd Street, Building 9, 2nd Floor, San Francisco, CA 94110. E-mail address for S. Morshed: morsheds@orthosurg.ucsf.edu.
authors.forename: Simon
authors.initials: S
authors.lastname: Knops
authors.affiliation: Denver Health Medical Center, 777 Bannock Street, Mail Code 0206, Denver, CO 80204.
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Jurkovich
authors.affiliation: University of Washington, Harborview Medical Center, 325 9th Avenue, Box 359660, Seattle, WA 98140.
authors.forename: Jin
authors.initials: J
authors.lastname: Wang
authors.affiliation: John Hopkins Bloomberg School of Public Health, 624 North Broadway, Room 462, Baltimore, MD 21205.
authors.forename: Ellen
authors.initials: E
authors.lastname: MacKenzie
authors.affiliation: University of Washington, Harborview Medical Center, 325 9th Avenue, Box 359660, Seattle, WA 98140.
authors.forename: Frederick P
authors.initials: FP
authors.lastname: Rivara
mesh_terms: D000077:Acetabulum / Q000293:injuries*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003362:Cost-Benefit Analysis; D055317:Evidence-Based Practice / Q000706:statistics & numerical data; D005260:Female; D050723:Fractures, Bone / Q000401:mortality* / Q000503:physiopathology*; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D010384:Pelvic Bones / Q000293:injuries*; D020127:Recovery of Function; D012306:Risk; D018570:Risk Assessment; D015996:Survival Rate; D014193:Trauma Centers / Q000191:economics / Q000706:statistics & numerical data*; D016896:Treatment Outcome; D014218:Triage; D014481:United States / Q000453:epidemiology; D055815:Young Adult