title: Factors affecting hospital charges after total shoulder arthroplasty: an evaluation of the National Inpatient Sample database.
abstract: BACKGROUND
  The number of total shoulder arthroplasties (TSA) performed in the United States increases yearly. At the same time, cost containment in health care continues to be a major concern. Therefore, it is imperative to identify specific variables that affect the cost of shoulder arthroplasty.
  
  
  METHODS
  The U.S. National Inpatient Sample database was queried (1993-2010) to evaluate total hospital charges for shoulder arthroplasty. Etiology of arthritis, multiple medical comorbidities, and patient and hospital demographics were evaluated for their effect on total inpatient hospital charges by a multivariate analysis.
  
  
  RESULTS
  Hospital charges for TSA increased from 1993 to 2010. Gender, race, and obesity were not associated with these differences in hospital charges. Post-traumatic and rheumatoid arthritis resulted in increased hospital charges; however, osteoarthritis resulted in decreased charges from the baseline. Multiple comorbidities (diabetes, lung disease, heart disease, and kidney disease) resulted in increased hospital charges after TSA. Regionally, the western and southern United States had the highest total charges above baseline. Larger hospitals and private urban hospitals also showed charges above baseline.
  
  
  CONCLUSIONS
  The factors related to increased hospital charges after TSA are multifactorial and include medical comorbidities, patient demographics, and regionalization. As the future of health care continues to evolve, it is important for practitioners, legislators, insurance administrators, and hospitals to recognize factors that increase costs.
authors.affiliation: Department of Orthopaedic Surgery, The Rothman Institute, Thomas Jefferson University Hospital, Philadelphia, PA, USA. Electronic address: daniel.e.davis@gmail.com.
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Davis
authors.affiliation: Department of Orthopaedic Surgery, Warren Alpert Medical School of Brown University, Providence, RI, USA.
authors.forename: E Scott
authors.initials: ES
authors.lastname: Paxton
authors.affiliation: Department of Orthopaedic Surgery, The Rothman Institute, Thomas Jefferson University Hospital, Philadelphia, PA, USA.
authors.forename: Mitchell
authors.initials: M
authors.lastname: Maltenfort
authors.affiliation: Department of Orthopaedic Surgery, The Rothman Institute, Thomas Jefferson University Hospital, Philadelphia, PA, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Abboud
mesh_terms: D001168:Arthritis / Q000601:surgery*; D019643:Arthroplasty, Replacement / Q000191:economics* / Q000706:statistics & numerical data*; D015897:Comorbidity; D016208:Databases, Factual; D005260:Female; D017722:Hospital Charges / Q000706:statistics & numerical data*; D006801:Humans; D007297:Inpatients / Q000706:statistics & numerical data; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D012782:Shoulder / Q000601:surgery; D012785:Shoulder Joint / Q000601:surgery*; D014481:United States / Q000453:epidemiology
keywords: Total shoulder arthroplasty; hospital charges; hospital size; medical comorbidities; patient demographics; regional variation