title: High failure rate of the Duraloc Constrained Inlay.
abstract: OBJECTIVE
  After total hip arthroplasty, dislocations are a frequent complication and are difficult to treat in some patients. A great variety of implants and antiluxation mechanisms are used in surgical therapy.
  
  
  METHODS
  8 patients had 9 Duraloc Constrained Inlays implanted at our clinic between October 2003 and November 2006, for recurrent dislocations. A retrospective follow-up study was carried out.
  
  
  RESULTS
  All patients suffered a failure of the expanding ring, the metal ring being squeezed out of the polyethylene notch. The mechanism of failure can be explained by impingement due to the implant design. At the time of writing, 3 patients have had to undergo revision surgery.
  
  
  CONCLUSIONS
  The Duraloc Constrained Inlay has shown unacceptably high failure rates.
authors.affiliation: Department of Orthopaedic Surgery, Medical University Innsbruck, Innsbruck, Austria. gerold.labek@efort.org
authors.forename: Gerold
authors.initials: G
authors.lastname: Labek
authors.forename: Erich
authors.initials: E
authors.lastname: Brabec
authors.forename: Stephan
authors.initials: S
authors.lastname: Frischhut
authors.forename: Martin
authors.initials: M
authors.lastname: Krismer
mesh_terms: D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D019544:Equipment Failure Analysis; D005500:Follow-Up Studies; D006622:Hip Prosthesis; D006801:Humans; D020959:Polyethylene; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012086:Reoperation; D012189:Retrospective Studies; D013997:Time Factors
chemical_list: D020959:Polyethylene