title: What are the causes for failures of primary hip arthroplasties in France?
abstract: BACKGROUND
  There are no large database cohorts describing the causes for failure of primary THAs in France. Because implants and causes for revision vary between national registers, it is important to obtain data from all countries.
  
  
  OBJECTIVE
  We therefore determined (1) the mechanisms of failure of primary THAs, (2) their order of appearance with time, (3) the types of surgical techniques and implant designs used to perform revision THAs, and (4) 90-day complications after revision THA in France.
  
  
  METHODS
  We prospectively collected data on all 2107 first-time revision THAs from 30 tertiary centers from January 1, 2010, to December 31, 2011. A dual-mobility liner had been used in 251 hips. Mean time from primary procedure to revision THA was 11.2 years (range, 1 day to 42 years). Mean age at revision was 70 years (range, 17-104 years).
  
  
  RESULTS
  The causes for revision were mechanical loosening (42%), periprosthetic fracture (12%), infection (11%), wear/osteolysis (11%), dislocation (10%), surgical technique error (6%), and implant fracture (3%). The most common type of revision procedure was all-component revision (49%). A dual-mobility liner was used in 1184 hips (62%). The 90-day dislocation rate was less than 4%, and mortality rate was 1.6%.
  
  
  CONCLUSIONS
  Contrary to other reported data, we found dislocation was not the main cause for failure of primary THAs but was still the more frequent early complication after revision. These findings might be related to the use of dual-mobility sockets in more than 10% of primary THAs and more than 60% of revision THAs.
authors.affiliation: Department of Orthopaedics, Clinique de l'Yvette, 67-69 Route de Corbeil, 91160, Longjumeau, France, c.delaunay@clinique-yvette.com.
authors.forename: Christian
authors.initials: C
authors.lastname: Delaunay
authors.forename: Moussa
authors.initials: M
authors.lastname: Hamadouche
authors.forename: Julien
authors.initials: J
authors.lastname: Girard
authors.forename: Alain
authors.initials: A
authors.lastname: Duhamel
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip; D016208:Databases, Factual; D005260:Female; D005602:France; D006617:Hip Dislocation / Q000150:complications* / Q000601:surgery; D006621:Hip Joint / Q000601:surgery*; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D057068:Periprosthetic Fractures / Q000150:complications* / Q000601:surgery; D011446:Prospective Studies; D011475:Prosthesis Failure / Q000209:etiology*; D016459:Prosthesis-Related Infections / Q000150:complications* / Q000601:surgery; D012086:Reoperation