title: [Analysis of the failures of a cemented constrained liner model in patients with a high dislocation risk].
abstract: OBJECTIVE
  To evaluate the short-term results of an ultra high molecular weight polyethylene retentive cup in patients at high risk of dislocation, either primary or revision surgery.
  
  
  METHODS
  Retrospective review of 38 cases in order to determine the rate of survival and failure analysis of a constrained cemented cup, with a mean follow-up of 27 months. We studied demographic data, complications, especially re-dislocations of the prosthesis and, also the likely causes of system failure analyzed.
  
  
  RESULTS
  In 21.05% (8 cases) were primary surgery and 78.95% were revision surgery (30 cases). The overall survival rate by Kaplan-Meier method was 70.7 months. During follow-up 3 patients died due to causes unrelated to surgery and 2 infections occurred. 12 hips had at least two previous surgeries done. It wasn't any case of aseptic loosening. Four patients presented dislocation, all with a 22 mm head (P=.008). Our statistical analysis didn't found relationship between the abduction cup angle and implant failure (P=.22).
  
  
  CONCLUSIONS
  The ultra high molecular weight polyethylene retentive cup evaluated in this series has provided satisfactory short-term results in hip arthroplasty patients at high risk of dislocation.
authors.affiliation: Unidad de Cadera, Servicio de Cirugía Ortopédica y Traumatología, ICEMEQ, Hospital Clínic, Universidad de Barcelona, Barcelona, España. Electronic address: xgallart@clinic.ub.es.
authors.forename: X
authors.initials: X
authors.lastname: Gallart
authors.affiliation: Unidad de Cadera, Servicio de Cirugía Ortopédica y Traumatología, ICEMEQ, Hospital Clínic, Universidad de Barcelona, Barcelona, España.
authors.forename: J C
authors.initials: JC
authors.lastname: Gomez
authors.affiliation: Unidad de Cadera, Servicio de Cirugía Ortopédica y Traumatología, ICEMEQ, Hospital Clínic, Universidad de Barcelona, Barcelona, España.
authors.forename: J A
authors.initials: JA
authors.lastname: Fernández-Valencia
authors.affiliation: Unidad de Cadera, Servicio de Cirugía Ortopédica y Traumatología, ICEMEQ, Hospital Clínic, Universidad de Barcelona, Barcelona, España.
authors.forename: A
authors.initials: A
authors.lastname: Combalía
authors.affiliation: Unidad de Cadera, Servicio de Cirugía Ortopédica y Traumatología, ICEMEQ, Hospital Clínic, Universidad de Barcelona, Barcelona, España.
authors.forename: G
authors.initials: G
authors.lastname: Bori
authors.affiliation: Unidad de Cadera, Servicio de Cirugía Ortopédica y Traumatología, ICEMEQ, Hospital Clínic, Universidad de Barcelona, Barcelona, España.
authors.forename: S
authors.initials: S
authors.lastname: García
authors.affiliation: Laboratory of Biostatistics & Epidemiology, Universitat Autònoma de Barcelona, Biostatistics and Data Management Core Facility, IDIBAPS, Hospital Clínic, Barcelona, España.
authors.forename: J
authors.initials: J
authors.lastname: Rios
authors.affiliation: Unidad de Cadera, Servicio de Cirugía Ortopédica y Traumatología, ICEMEQ, Hospital Clínic, Universidad de Barcelona, Barcelona, España.
authors.forename: J
authors.initials: J
authors.lastname: Riba
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001843:Bone Cements; D005260:Female; D006622:Hip Prosthesis; D006801:Humans; D004204:Joint Dislocations; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012086:Reoperation; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D001843:Bone Cements
keywords: Cirugía de revisión; Constrained cup; Cotilo constreñido; Dislocation; Hip arthroplasty; Luxación; Prótesis de cadera; Revision surgery; Supervivencia; Survival