title: Relationship between peri-operative outcomes and hospital surgical volume of total hip arthroplasty in Japan.
abstract: BACKGROUND
  This study aimed to evaluate the relationship between peri-operative complication of total hip arthroplasty (THA) and hospital surgical volume.
  
  
  METHODS
  We reviewed discharge administrative data from 8321 patients who underwent primary THA between July and December 2008. Relationships between complications and surgical volume were analyzed with multivariate logistic regression models including age, sex, and Charlson comorbidity index. Hospitals were categorized into four groups according to the 6-month volume of THA procedures.
  
  
  RESULTS
  The most frequent complication was dislocation (1.41%). Next was infection (1.24%). Fracture and pulmonary embolism occurred in less than 1% of procedures. Patients who underwent THA in hospitals with the highest surgical volume had lower risk of dislocation and infection than those treated in the hospitals with the lowest surgical volume (odds ratio [OR] 0.321, 95% confidence interval [CI] 0.167-0.572 and OR 0.123, 95% CI 0.020-0.421). Patients aged 65 years and older were associated with increased risk of dislocation (OR 2.342, CI 1.555-3.624) and fracture (OR 2.799, CI 1.372-6.301). Females demonstrated lower risk of dislocation (OR 0.558, CI 0.352-0.869) and infection (OR 0.560, CI 0.365-0.882).
  
  
  CONCLUSIONS
  These results indicated that the increase in the risk of peri-operative dislocation of primary THA may be associated with low hospital surgical volume as well as age and male sex.
authors.affiliation: Department of Health Policy and Informatics, Tokyo Medical Dental University, Graduate School, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan. Electronic address: tkan.hci@tmd.ac.jp.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kaneko
authors.affiliation: Shonan Kamakura Joint Reconstruction Center, 5-4-17 Dai Kamakura, Kanagawa 247-0061, Japan. Electronic address: hirakawa-k1@skjrc.jp.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Hirakawa
authors.affiliation: Department of Health Policy and Informatics, Tokyo Medical Dental University, Graduate School, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan. Electronic address: kfushimi.hci@tmd.ac.jp.
authors.forename: Kiyohide
authors.initials: K
authors.lastname: Fushimi
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000706:statistics & numerical data*; D004469:Economics, Hospital; D017558:Elective Surgical Procedures; D005260:Female; D061847:Hospitals, High-Volume; D061846:Hospitals, Low-Volume; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D059035:Perioperative Period; D011183:Postoperative Complications / Q000453:epidemiology*; D011787:Quality of Health Care; D012307:Risk Factors; D012737:Sex Factors; D016896:Treatment Outcome; D055815:Young Adult
keywords: Complication; Hospital surgical volume; Peri-operative outcome; Quality of care; Total hip arthroplasty