title: Selection of allografts for impaction bone grafting for bone defect reconstruction on the acetabular side.
abstract: OBJECTIVE
  To review the choices of allografts for bone defect reconstruction in acetabular revision surgery using the technique of impaction bone grafting.
  
  
  METHODS
  The data cited in this review were mainly obtained from articles listed in PubMed that were published from January 1993 to July 2009. The search terms were "impaction bone grafting", "particle size", "mechanical property" and "biological behavior".
  
  
  METHODS
  Articles relevant to the choices of allografts and their results for bone defect reconstruction on the acetabular side were selected.
  
  
  RESULTS
  Different choices of allografts, including the particle size, process of irradiation or fat reduction, composition and particle grade, are made to improve the survival rate of a prosthesis in acetabular revision surgery. This review, which compares both mechanical and biological factors, summarizes the experimental and clinical results for different techniques.
  
  
  CONCLUSIONS
  Fresh frozen cancellous allografts with particle sizes ranging from 7 to 10 mm are a favorable choice for reconstruction of bone defects of American Academy of Orthopedic Surgeons (AAOS) types II (cavitary defect) and III (combined cavitary and segmental defect) on the acetabular side. A fat-reducing procedure with saline or solvent/detergent is controversial. Adding autologous marrow into irradiated allografts, which provides reliable mechanical stability and biological safety, may be a substitute for fresh frozen allografts. Cortical bone can be a supplementary material in cases of insufficiency of cancellous allografts. Cartilage should be excluded from the graft material. Further research is required to demonstrate the best particle grade, and randomized controlled trials in clinical practice are required to obtain more information about the selection of allografts.
authors.affiliation: Department of Orthopaedic Surgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310009, China.
authors.forename: Zheng-Jian
authors.initials: ZJ
authors.lastname: Xu
authors.forename: Rong-Xin
authors.initials: RX
authors.lastname: He
mesh_terms: D000077:Acetabulum / Q000601:surgery*; D016025:Bone Transplantation / Q000379:methods*; D006801:Humans; D019651:Plastic Surgery Procedures / Q000379:methods*; D014184:Transplantation, Homologous / Q000379:methods