On the design and properties of porous femoral stems with adjustable stiffness gradient.

•The admissible parametric design space is established in terms of bone ingrowth and manufacturability requirements.•The homogenous stems with 50% and 60% of porosity produce excessive interface micromotions.•Graded femoral stems drove to better results homogeneous ones.•Axially graded stems with higher distal stiffness and radially graded stems with higher inner stiffness resulted better in terms of osseointegration and reduction of bone loss.