Bone graft for revision hip arthroplasty: biology and future applications

Revision total hip arthroplasty often presents surgeons with difficult bone loss problems. The selection of an appropriate bone graft is influenced by the size of the bone defect, the location, the biology of the bone graft site, and whether the graft is required for structural support. Autogenous bone graft remains the gold standard bone graft material but there only is a limited amount available and there is morbidity associated with the harvesting of these grafts. The most frequently used bone graft materials include autogenous iliac crest bone graft, cancellous allograft chips, demineralized bone matrix, and bulk structural allografts (femoral head, distal or proximal femoral allograft, whole acetabuli, and femoral strut grafts). It often is difficult to determine on plain radiographs whether nonstructural grafts actually incorporate into the host bone. Recently, attention has focused on the use of new materials for bone grafting including: new demineralized bone matrices, ceramics, autologous platelet concentrates, recombinant proteins, and stem cells. The purpose of this review was to assess the biologic potential of these nonstructural grafts in revision hip arthroplasty and their limitations. Are these agents actually incorporating into host bone? Future bone graft options, including tissue engineering and gene therapy will be discussed briefly.