title: Use of dual-mobility cup in revision hip arthroplasty reduces the risk for further dislocation: analysis of seven hundred and ninety one first-time revisions performed due to dislocation, reported to the Swedish Hip Arthroplasty Register.
abstract: Dislocation after total hip arthroplasty (THA) is a common reason for revision. The last decade fostered a significant increase in the use of dual-mobility cups (DMCs). Here we report our study on the short-term survival rate of a cemented DMC reported to the Swedish Hip Arthroplasty Register (SHAR) compared with other cemented designs used in first-time revision due to dislocation.
  
  
  
  During 2005-2015, 984 first-time revisions for dislocation were reported to SHAR. In 436 of these cases a cemented dual articular cup was used. During the same time period, 355 revisions performed with a standard cemented cup (femoral head size 28-36 mm) were reported to the SHAR. Patients receiving a DMC were slightly older (75 years, p = 0.005). Re-revision for all reasons was used as primary endpoint. We also anlaysed risk for re-revision of the acetabular component and re-revision due to dislocation. Kaplan-Meier implant survival and a Cox regression analyses adjusted for age and gender were performed.
  
  
  
  Implant survival at 4 years for all reasons (91% ± 3.7% vs 86% ± 4.1%, p = 0.02), and especially for re-operation because of dislocation, favours the DMC group (96% ± 3.0% vs 92% ± 3.3%, p = 0.001).
  
  
  
  Our findings indicate that use of a cemented DMC reduces the short- to mid-term risk of a second revision in first-time revisions compared with classic cup designs. Longer follow-up is needed to establish any long-term clinical advantages when DMCs are used in revisions performed due to dislocation.
authors.affiliation: Department of Orthopaedics, Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. Maziar.mohaddes@gmail.com.|Swedish Hip Arthroplasty Register, Registercentrum VGR, SE-413 45, Göteborg, Sweden. Maziar.mohaddes@gmail.com.
authors.forename: Maziar
authors.identifier: 0000-0003-1848-9054
authors.initials: M
authors.lastname: Mohaddes
authors.affiliation: Department of Orthopaedics, Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.|Swedish Hip Arthroplasty Register, Registercentrum VGR, SE-413 45, Göteborg, Sweden.|Hywel Dda University Health Board, Llanelli, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Cnudde
authors.affiliation: Department of Orthopaedics, Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.|Swedish Hip Arthroplasty Register, Registercentrum VGR, SE-413 45, Göteborg, Sweden.
authors.forename: Ola
authors.initials: O
authors.lastname: Rolfson
authors.affiliation: Department of Orthopaedics, Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.|Swedish Hip Arthroplasty Register, Registercentrum VGR, SE-413 45, Göteborg, Sweden.
authors.forename: Alexander
authors.initials: A
authors.lastname: Wall
authors.affiliation: Department of Orthopaedics, Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.|Swedish Hip Arthroplasty Register, Registercentrum VGR, SE-413 45, Göteborg, Sweden.
authors.forename: Johan
authors.initials: J
authors.lastname: Kärrholm
mesh_terms: D000328:Adult; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects / Q000379:methods*; D001843:Bone Cements; D005260:Female; D006617:Hip Dislocation / Q000209:etiology / Q000601:surgery*; D006621:Hip Joint / Q000601:surgery; D006622:Hip Prosthesis / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011475:Prosthesis Failure / Q000209:etiology; D012042:Registries; D012086:Reoperation / Q000379:methods*; D015996:Survival Rate; D013548:Sweden
chemical_list: D001843:Bone Cements
keywords: Dislocation; Register studies; Revision