title: The Epidemiology of Primary and Revision Total Hip Arthroplasty in Teaching and Nonteaching Hospitals in the United States.
abstract: BACKGROUND
  The purpose of this study was to examine the epidemiology of primary and revision total hip arthroplasty (THA) in teaching and nonteaching hospitals.
  
  
  METHODS
  The Healthcare Cost and Utilization Project Nationwide Inpatient Sample was queried from 2006 to 2010 to identify primary and revision THAs at teaching and nonteaching hospitals.
  
  
  RESULTS
  A total of 1,336,396 primary and 223,520 revision procedures were identified. Forty-six percent of all primary and 54% of all revision procedures were performed at teaching hospitals. Teaching hospitals performed 17% of their THAs as revisions; nonteaching hospitals performed 12% as revisions. For primary and revision THAs, teaching hospitals had fewer patients aged >65 years, fewer Medicare patients, similar gender rates, more nonwhite patients, and more patients in the highest income quartile compared with nonteaching hospitals. Costs, length of stay, and Charlson Comorbidity Index scores were similar; however, the mortality rate was lower at teaching hospitals.
  
  
  CONCLUSIONS
  This study found small but significant differences in key epidemiologic and outcome variables in examining primary and revision THA at teaching and nonteaching hospitals.
  
  
  METHODS
  Level III.
authors.affiliation: From the Department of Orthopaedics, Oregon Health and Science University, Portland, OR (Dr. Kowalik, Dr. Schabel, and Paxton Gehling), Providence Health and Services, Portland (Mr. DeHart and Hanne Gehling), Orthopedic & Fracture Specialists, Portland (Dr. Duwelius), and Summit Orthopaedics, Portland (Dr. Mirza).
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Kowalik
authors.forename: Matthew
authors.initials: M
authors.lastname: DeHart
authors.forename: Hanne
authors.initials: H
authors.lastname: Gehling
authors.forename: Paxton
authors.initials: P
authors.lastname: Gehling
authors.forename: Kathryn
authors.initials: K
authors.lastname: Schabel
authors.forename: Paul
authors.initials: P
authors.lastname: Duwelius
authors.forename: Amer
authors.initials: A
authors.lastname: Mirza
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000706:statistics & numerical data*; D005260:Female; D017048:Health Care Costs / Q000706:statistics & numerical data; D017052:Hospital Mortality; D006761:Hospitals / Q000706:statistics & numerical data*; D006784:Hospitals, Teaching / Q000706:statistics & numerical data*; D006801:Humans; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology; D012086:Reoperation / Q000706:statistics & numerical data*; D014481:United States / Q000453:epidemiology