title: The use of structural periacetabular allografts in acetabular revision surgery: 2.5-5 years follow-up.
abstract: BACKGROUND
  "Acetabular bone loss" presents a major reconstructive challenge in total hip arthroplasty. Loss of acetabular bone stock is a consequence of removal of bone during the original procedure, subsequent prosthetic failure and osteolysis resulting from wear particles of cement and polyethylene. In case of severe bone loss treatment options are rather limited, as fixation requires either biological (cancellous allograft with cage or structural allograft) or non-biological (trabecular metal, triflange implant, etc.) scaffolds.
  
  
  METHODS
  Fourteen acetabular revisions with a cemented cup, supported by a deep frozen structural periacetabular allograft without using a reinforcement ring or an antiprotrusio cage were performed. Clinical assessment was done using a Harris hip score. Graft resorption was radiographically quantified using a digital measurement program.
  
  
  RESULTS
  Kaplan-Meier survivorship was 67.1% at 42 months. After a mean follow-up of 3.6 years, 9 out of 14 patients had good clinical results. Mean resorption of 17.1% in six out of ten patients was observed. No sound evidence for union was found in nine out of ten patients. In the four re-revised patients, no bone stock restoration was found.
  
  
  CONCLUSIONS
  The bicortical allograft without protective device seems to function as a passive biocompatible dead scaffold, which has a less intrinsic strength at intermediate term follow-up, compared to the by ring or cage protected structural allografts.
authors.affiliation: Department of Orthopedic Surgery, University Hospitals Louvain, Catholic University Louvain, Louvain, Belgium.
authors.forename: S
authors.initials: S
authors.lastname: Schelfaut
authors.forename: S
authors.initials: S
authors.lastname: Cool
authors.forename: M
authors.initials: M
authors.lastname: Mulier
mesh_terms: D000077:Acetabulum / Q000601:surgery*; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D001862:Bone Resorption; D016025:Bone Transplantation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D019651:Plastic Surgery Procedures / Q000379:methods; D012086:Reoperation; D014184:Transplantation, Homologous