title: High proximal migration in cemented acetabular revisions operated with bone impaction grafting; 47 revision cups followed with RSA for 17 years.
abstract: BACKGROUND
  Bone impaction grafting is a biologically and mechanically appealing option in acetabular revision surgery, allowing restitution of the bone stock and restoration of the biomechanics. We analysed differences in proximal migration of the revision acetabular components when bone impaction grafting is used together with a cemented or an uncemented cup.
  
  
  METHODS
  43 patients (47 hips), revised due to acetabular loosening and judged to have less than 50% host bone-implant contact were included. The hips were randomised to either an uncemented (n = 20) or a cemented (n = 27) revision cup. Radiostereometry and radiography was performed postoperatively, at 3 and 6 months, 1, 2, 3, 5, 7, 10 and 13 and 17 years postoperatively. Clinical follow-up was performed at 1, 2 and 5 years postoperatively and thereafter at the same interval as in the radiographic follow-up.
  
  
  RESULTS
  There were no differences in the base line demographic data between the 2 groups. At the last follow-up (17 years) 14 hips (10 cemented, 4 uncemented) had been re-revised due to loosening. 3 additional cups (1 uncemented and 2 cemented) were radiographically loose. There was a higher early proximal migration in the cemented cups.
  
  
  CONCLUSIONS
  Cups operated on with cement showed a higher early migration measured with RSA and also a higher number of late revisions. The reason for this is not known, but factors such as inclusion of cases with severe bone defects, use of smaller bone chips and issues related to the impaction technique might have had various degrees of influence.
authors.affiliation: Department of Orthopaedics, Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, Gothenburg - Sweden.
authors.forename: Maziar
authors.initials: M
authors.lastname: Mohaddes
authors.affiliation: Department of Orthopaedics, Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, Gothenburg - Sweden.
authors.forename: Peter
authors.initials: P
authors.lastname: Herberts
authors.affiliation: Department of Orthopaedics, Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, Gothenburg - Sweden.
authors.forename: Henrik
authors.initials: H
authors.lastname: Malchau
authors.affiliation: Department of Orthopaedics, Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, Gothenburg - Sweden.
authors.forename: Per-Erik
authors.initials: PE
authors.lastname: Johanson
authors.affiliation: Department of Orthopaedics, Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, Gothenburg - Sweden.
authors.forename: Johan
authors.initials: J
authors.lastname: Kärrholm
mesh_terms: D000077:Acetabulum / Q000000981:diagnostic imaging / Q000601:surgery*; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D001843:Bone Cements; D016025:Bone Transplantation / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D005544:Forecasting; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D015207:Osteoarthritis, Hip / Q000175:diagnosis / Q000601:surgery*; D011475:Prosthesis Failure; D011859:Radiography; D059869:Radiostereometric Analysis; D012086:Reoperation; D012189:Retrospective Studies
chemical_list: D001843:Bone Cements