Effect of bone ingrowth and acetabular geometry on load transfer and distribution in total hip arthroplasty

摘要

Early acetabular implants were constructed entirely of polyethylene and bonded to the acetabulum via bone cement. During implantation, the dense sub-chondral bone layer was sometimes removed, decreasing the rigidity of the bone construct andincreasing the stresses in the bone, cement, and implant [Pedersen et al, 1982]. In an effort to provide component modularity and a more rigid substructure for the polyethylene, most current implants have a metal backing. The presence of a metal backingalso allows the subchondral cortical bone to be removed, which permits the use of larger implants, improves the initial seating of the implant, and increases the likelihood of porous ingrowth.The objective of this finite element analysis was to determine the stress/strain distribution in the acetabulum, and the sensitivity of this hip/implant construct to changes in the amount of porous ingrowth and the absence of a subchondral bone layer.