title: Time trends and risk factors for perioperative complications in total ankle arthroplasty: retrospective analysis using a national database in Japan.
abstract: Total ankle arthroplasty (TAA) has become increasingly popular worldwide as an alternative to ankle arthrodesis for surgical treatment of end-stage ankle arthritis. The aim of this epidemiological study, using a national inpatient database in Japan, was to describe the volume, utilization, patient characteristics, and temporal trends regarding these procedures in Japan, and to identify the risk factors associated with perioperative adverse events in TAA.
  
  
  
  This was a population-based, retrospective cohort study. We retrospectively identified 2775 patients in the Diagnosis Procedure Combination database who underwent ankle arthrodesis or TAA for ankle arthritis at 559 hospitals in Japan from 2007 to 2013. Information on sex, age, main diagnosis, use of blood transfusion, duration of anesthesia, length of hospital stay, in-hospital mortality, hospitalization costs, additional procedures after primary surgery, and use of negative pressure wound therapy was extracted. Multivariable logistic regression analysis was performed to analyze the effect of various factors on the incidence of perioperative adverse events in TAA, including additional procedure during hospitalization, negative pressure wound therapy, blood transfusion, and in-hospital death.
  
  
  
  We identified 465 patients who underwent TAA and 2310 patients who underwent ankle arthrodesis. There was no apparent increase in the proportion of TAAs performed during the survey period. Patients undergoing TAA tended to be older, female, and have rheumatoid arthritis compared with those undergoing ankle arthrodesis. Patients undergoing TAA had shorter length of stay, higher hospitalization costs, and more blood transfusions compared with those undergoing ankle arthrodesis. Lower hospital volume and shorter anesthesia time were associated with higher rates of adverse events after TAA.
  
  
  
  Despite an increase in the popularity of TAA internationally, the number of TAAs performed remains low in Japan. Lower hospital volume and anesthesia time were associated with higher rates of perioperative adverse events after TAA.
  
  
  
  IV, Cross-sectional study.
authors: Department of Orthopaedic Surgery, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan. matumot-tky@umin.ac.jp.
authors: Takumi
authors: T
authors: Matsumoto
authors: Department of Clinical Epidemiology and Health Economics, School of Public Health, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
authors: Hideo
authors: H
authors: Yasunaga
authors: Department of Clinical Epidemiology and Health Economics, School of Public Health, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
authors: Hiroki
authors: H
authors: Matsui
authors: Department of Health Policy and Informatics, Tokyo Medical and Dental University Graduate School, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-0034, Japan.
authors: Kiyohide
authors: K
authors: Fushimi
authors: Department of Orthopaedic Surgery, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
authors: Naohiro
authors: N
authors: Izawa
authors: Department of Orthopaedic Surgery, Teikyo University Mizonokuchi Hospital, 3-8-3 Mizonokuchi, Takatsu-ku, Kawasaki, 213-8507, Japan.
authors: Tetsuro
authors: T
authors: Yasui
authors: Department of Orthopaedic Surgery, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
authors: Yuho
authors: Y
authors: Kadono
authors: Department of Orthopaedic Surgery, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
authors: Sakae
authors: S
authors: Tanaka
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000843:Ankle Joint / Q000601:surgery*; D001172:Arthritis, Rheumatoid / Q000453:epidemiology / Q000601:surgery*; D001174:Arthrodesis / Q000009:adverse effects* / Q000706:statistics & numerical data / Q000639:trends; D058737:Arthroplasty, Replacement, Ankle / Q000009:adverse effects* / Q000706:statistics & numerical data / Q000639:trends; D003430:Cross-Sectional Studies; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D015994:Incidence; D007431:Intraoperative Complications / Q000453:epidemiology*; D007564:Japan / Q000453:epidemiology; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D061646:Operative Time; D020370:Osteoarthritis, Knee / Q000453:epidemiology / Q000601:surgery*; D059035:Perioperative Period / Q000706:statistics & numerical data; D011183:Postoperative Complications / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors
keywords: Ankle arthrodesis; Ankle arthroplasty; Ankle fusion; Low-volume hospitals; Outcomes; Trends